Extract
This update is based on the scientific and investigational activities in the specialty of sports medicine from September 2006 to August 2007. It includes a review of pertinent research and articles published in the three premier journals of our specialty, namely, The Journal of Bone and Joint Surgery (American Volume), The American Journal of Sports Medicine, and Arthroscopy. It also takes into account the scientific presentations of the annual and Specialty Day meetings of the American Academy of Orthopaedic Surgeons (AAOS), the American Orthopaedic Society for Sports Medicine (AOSSM), and the Arthroscopy Association of North America (AANA).
This update is based on the scientific and investigational activities in the specialty of sports medicine from September 2006 to August 2007. It includes a review of pertinent research and articles published in the three premier journals of our specialty, namely, The Journal of Bone and Joint Surgery (American Volume), The American Journal of Sports Medicine, and Arthroscopy. It also takes into account the scientific presentations of the annual and Specialty Day meetings of the American Academy of Orthopaedic Surgeons (AAOS), the American Orthopaedic Society for Sports Medicine (AOSSM), and the Arthroscopy Association of North America (AANA).
Anterior Cruciate Ligament
Injuries involving the anterior cruciate ligament are among the most commonly encountered conditions within the realm of sports medicine. As athletics continue to become more competitive, we strive as a profession to improve on already excellent results. The literature contains more articles relating to anterior cruciate ligament reconstruction than perhaps any other topic in sports medicine. Issues of interest include graft choice and fixation method, tunnel placement, development of osteoarthritic changes, quadriceps strength and inhibition after ligament reconstruction, double-bundle reconstructions, graft rupture rates, and revision procedures.
Two autograft choices continue to predominate: (1) the bone-patellar tendon-bone autograft and (2) the quadruple-strand hamstring autograft consisting of the semitendinosus and gracilis tendons. While the bone-patellar tendon-bone autograft has long been considered the gold standard, use of the hamstring graft continues to increase in popularity and is the graft of choice for many surgeons. A comparison of these two grafts remains the focus of numerous studies. In general, the subjective and clinical outcomes are equivalent, as documented in three separate randomized clinical trials1-3. Most, although not all, studies have documented increased harvest-site symptoms in association with patellar tendon grafts in the form of anterior knee pain and difficulty kneeling. Although ipsilateral autografts were harvested in these studies, contralateral grafts were advocated in at least one previous study. We are aware of no recent investigations in which ipsilateral autografts have been compared with contralateral autografts, and proponents for each exist.
An additional issue related to graft choice that has been explored in the recent literature is the subsequent development of osteoarthritis. Several studies have documented an increased incidence of osteoarthritis following treatment with patellar tendon grafts as opposed to hamstring grafts. One level-I study demonstrated abnormal radiographic findings consistent with osteoarthritis in 50% of patients with patellar tendon autografts and 17% of those with hamstring grafts after five years of follow-up3. Another study demonstrated early tibiofemoral osteoarthritis in 62% of patients with patellar tendon grafts and 33% of those with hamstring grafts after six years of follow-up4. That study also demonstrated a 6% residual quadriceps deficit after patellar tendon harvesting. Although the majority of the arthritic changes found in those studies were mild, longer-term follow-up is needed to document further progression and clinical importance.
The issue of quadriceps function surrounding anterior cruciate ligament reconstruction is of interest as it may be a possible explanation for the increased incidence of osteoarthritis in this population, particularly after treatment with a patellar tendon graft. One study examining preoperative and postoperative quadriceps strength demonstrated that while preoperative deficits existed, the deficits increased postoperatively and peaked at six months5. At one year of follow-up, a deficit of nearly 20% persisted. Quadriceps strength was correlated with general functional performance. Higher deficits were present in patients with patellar tendon grafts. Another study involving an experimental knee joint effusion model demonstrated an association with quadriceps inhibition and altered knee joint mechanics6. In that study, the subjects' knees were injected with saline solution and the subjects performed specific landing tasks. Subjects who were subjected to the high-effusion condition (induced with a 60-mL injection) displayed quadriceps inhibition with larger ground-reaction forces and greater knee extension. It was postulated that these factors may subsequently increase the risk of future knee joint trauma or degeneration. The findings of those studies potentially provide a correlation between patellar tendon grafts, quadriceps inhibition, and future osteoarthritis. However, additional research is needed to confirm these hypotheses and to determine whether quadriceps rehabilitation can influence the development of osteoarthritis.
A variety of allografts comprise additional graft options. While the use of allografts may expedite the procedure by decreasing operative time and may eliminate donor-site issues, concerns still exist. The risk of disease transmission cannot be eliminated. Bacterial contamination is an additional concern that may or may not prove to be clinically important when addressed appropriately. The literature also has documented decreased biomechanical properties and higher rates of failure in association with allograft use. One study in particular addressed the use of anterior tibialis allografts for anterior cruciate ligament reconstruction7. The overall rate of reoperation was 37.7%. The rate of revision because of graft failure was 23%. In patients who were twenty-five years of age or younger, the failure/reoperation rate was 55%. On the basis of these data, allografts cannot be recommended as the ideal graft choice for routine primary reconstructions, particularly in the young patient.
Multiple graft-fixation methods exist. Several biomechanical studies have evaluated various fixation methods for soft-tissue grafts, with a particular emphasis on bioabsorbable as opposed to metal interference screws. Overall, those studies have shown a mechanical preference for bioabsorbable screws, which have been associated with increased fixation strength and decreased risk of injury to the graft. A clinical study comparing these two types of interference screws, however, demonstrated equivalent results at the time of the two-year follow-up8. While the bioabsorbable screws were associated with significantly larger visible drill-holes on radiographs, this finding did not correlate with inferior clinical results. Composite bioabsorbable interference screws with the addition of hydroxyapatite or tricalcium phosphate have also been studied, with no proven benefit in comparison with standard bioabsorbable screws after two years of follow-up9. Fixation methods continue to evolve. Multiple methods will continue to be used on the basis of surgeon preference until a clearly superior method is demonstrated.
Perhaps the most common technical reason for the failure of anterior cruciate ligament reconstruction is aberrant tunnel placement. Improved cognizance of this potential pitfall has led to heightened intraoperative vigilance as well as to studies documenting ideal tunnel placement. As this knowledge continues to evolve, grafts are being placed more horizontally, with improved stability and better clinical results. Clinical studies have again confirmed an association between vertical tunnel placement and persistent rotational instability with a positive pivot shift despite an improvement in anteroposterior laxity with a negative Lachman examination.
The concept of double-bundle anterior cruciate ligament reconstruction continues to generate numerous investigations and articles. It is well known that the anterior cruciate ligament has both anteromedial and posterolateral bundles. Traditional reconstructions primarily restore the anteromedial bundle. However, as discussed above, tunnels and grafts are being placed more horizontally than has been described traditionally, creating in essence a posterolateral bundle. In any event, proponents of double-bundle reconstruction suggest that a more anatomic reconstruction will result in improved outcomes. Biomechanically, this theory has been confirmed with laboratory studies that have shown a synergistic interaction between the two bundles against anterior tibial translation and rotational forces. Clinical studies, however, have had more varied results. In one study with an average duration of follow-up of twenty-five months, patients were randomized to either single-bundle or double-bundle reconstruction10. No significant differences in subjective findings were found between the groups, although the double-bundle group had superior results on knee-stability testing. In contrast, a retrospective study of single-bundle and double-bundle reconstructions demonstrated no significant differences between the two groups in terms of knee stability or subjective results after an average duration of follow-up of thirty-three months11. Longer-term follow-up is necessary to document a clear benefit of double-bundle as opposed to single-bundle reconstruction and to identify potential complications. At this point, in part because of the lack of standardized guides, the technique is not easily reproducible among surgeons. Given the equivalent clinical results discussed above, routine use of double-bundle reconstruction is not yet recommended for all surgeons. A thorough review of double-bundle reconstructions is available for those wishing to further pursue this topic12.
Revision anterior cruciate ligament reconstruction is generally regarded to be associated with inferior clinical results as compared with primary procedures. One study in particular provided excellent guidance with regard to counseling patients about the risk of graft failure and the subsequent need for revision surgery13. The Multicenter Orthopaedic Outcomes Network (MOON) database was used to identify a large cohort of patients with two years of follow-up. Among the 235 patients who were studied, there were fourteen ligament disruptions, including seven graft failures (3%) and seven tears of the normal contralateral anterior cruciate ligament (3%). Therefore, patients may be counseled that the risk of graft failure is low (3%) and is similar to the risk of tearing the normal contralateral ligament. Regarding the outcomes of revision procedures, two separate studies documented a 10% failure rate and a high incidence of articular cartilage damage and degenerative changes in this patient population after a minimum duration of follow-up of five years.
Posterior Cruciate Ligament
The posterior cruciate ligament is less commonly injured than the anterior cruciate ligament is. Isolated posterior cruciate ligament injuries typically are treated nonoperatively. In contrast, combined or multiligamentous injuries often require operative reconstruction. A cadaver study that was presented at the meeting of the AOSSM demonstrated the importance of addressing combined posterior cruciate ligament and posterolateral corner injuries. The literature in this area also highlights the operative treatment of combined ligamentous injuries, with a focus on reconstruction techniques and double-bundle reconstructions.
The posterior cruciate ligament consists of anterolateral and posteromedial portions, or bundles. The anterolateral bundle is considered to be the more important bundle. When reconstructed, the anterolateral bundle should be tensioned and fixed in 90° of knee flexion and the posteromedial bundle should be tensioned and fixed in 0° of flexion to ensure appropriate tension throughout a full arc of motion14. Single-bundle reconstructions, in contrast, focus on reconstituting only the anterolateral bundle. A biomechanical study confirmed the relatively minor role of the posteromedial bundle in overall function of the posterior cruciate ligament15. Isolated sectioning of the posteromedial bundle resulted in small increases in posterior tibial translation at 0° and 10° of flexion. No increased laxity was noted at 30°, 45°, 70°, and 90°. In addition, the forces in the anterolateral bundle were not increased at any flexion angle after sectioning of the posteromedial bundle. A second clinical study of double-bundle reconstructions concluded that the results were no better than those of single-bundle reconstructions at the time of the three-year follow-up16. Posterior tibial laxity was improved but was not normalized in all patients. None of the patients were able to return to their preinjury level of activity. These data support the use of single-bundle reconstructions.
Posterolateral Corner
The posterolateral corner structures have received increased attention over the past several years. The main posterolateral corner structures are the lateral collateral ligament, the popliteus tendon, and the popliteofibular ligament. The biceps femoris is often involved as well. Injuries to the posterolateral corner are often associated with a cruciate ligament injury. Failure to recognize and treat the posterolateral corner structures increases the risk of failure of cruciate grafts.
Multiple techniques have been described for the repair or reconstruction of the posterolateral corner structures. If identified early and treated within the first two to three weeks, a primary repair may be possible. Recently, an en masse repair of the lateral structures was described in a study of patients with multiligamentous injuries after knee dislocation17. All but one of the patients underwent concomitant anterior cruciate ligament reconstruction. Posterior cruciate ligament injuries were not reconstructed. At the time of follow-up (at approximately five years), mild lateral and posterior laxity were present in only a small percentage of patients. The posterior cruciate ligament was considered to be healed and intact in all patients.
When the injury is chronic or the tissues are inadequate for repair, as is often the case, reconstructive procedures must be undertaken. Reconstruction of the lateral collateral ligament with a bone-patellar tendon-bone graft has been shown to be successful, with varus and external tibial rotational stability being restored in 93% of patients18. Reconstruction of all posterolateral structures with the biceps femoris tendon is also highly effective, with stability being restored in 96% of patients19. The posterior slip of the tendon is used to reconstruct the popliteofibular ligament and popliteus tendon, and an anterior slip is used to reconstruct the lateral collateral ligament. With all reconstructions, care should be taken to avoid overtensioning the grafts, which may lead to excessively constrained varus rotation.
Meniscus
Meniscal tears are perhaps the most common problem encountered in the orthopaedic sports medicine office. The preservation of meniscal tissue is ideal. While the indications for meniscal repair have been well established, the methods of meniscal repair continue to evolve. The gold standard remains inside-out vertical mattress suturing. Multiple all-inside arthroscopic devices have been developed in an effort to decrease the surgical time, technical difficulty, and morbidity of open exposures that place the neurovascular structures at risk.
In a recent clinical trial, 100 patients were randomized to meniscal repair with either inside-out sutures or bioabsorbable arrows (Bionx, Blue Bell, Pennsylvania)20. After a mean duration of follow-up of twenty-eight months, there was an overall failure rate of 22%, with an equal number of failures in each group. Of note, nearly 10% of the patients in the arrow group also required the use of inside-out sutures at the time of the procedure for technical reasons related to the arrows. Two additional patients required a reoperation for the removal of arrow devices. Other reports with longer durations of follow-up have shown less optimistic results and, in fact, have shown unacceptable failure rates of as high as 40% in association with the arrows. Consideration also must be given to potential articular cartilage damage secondary to the arrows with longer-term follow-up. Because of these concerns, the bioabsorbable arrow is not recommended as the preferred meniscal repair device.
The RapidLoc (DePuy Mitek, Westwood, Massachusetts) is another all-inside meniscal repair device that has shown improved results, with one study21 demonstrating an early clinical success rate of 87.5%. An animal study that was presented at the meeting of the AOSSM, however, demonstrated poorer healing rates in association with the RapidLoc device as compared with inside-out suture repair. Currently, inside-out suture repair remains the most reliable construct. The all-inside repair devices probably should be reserved for certain circumstances, such as repairable tears in the posterior meniscal horn in the setting of anterior cruciate ligament reconstruction. Additional research will help to further define their indications and results.
Finally, it is well known that meniscal healing is enhanced with concomitant anterior cruciate ligament reconstruction. This concept must be considered when evaluating the literature on healing rates following meniscal repair. The association has also led some surgeons to the supplemental use of platelet-rich fibrin clot when meniscal repair is performed without cruciate reconstruction. We are not aware of any recent studies comparing meniscal repairs with and without the use of fibrin clot.
Occasionally, meniscal tears are encountered that are not amenable to repair or limited resection. In a select number of these patients with nearly complete loss of the meniscus, meniscal transplantation may be an option. It is known that meniscectomy predisposes to later degenerative changes. This progression occurs much more rapidly in the lateral compartment. The indications for meniscal transplantation continue to be defined. It is believed that, in the appropriate patient, meniscal transplantation will prevent or at least delay degeneration of the knee joint. However, this correlation has not yet been firmly established. In fact, a recent study of twenty-two meniscal allografts (fourteen medial and eight lateral) demonstrated a 55% failure rate at ten years of follow-up despite improvement in Lysholm and pain scores in 90% of the patients22. Ten of fifteen allografts with radiographic follow-up displayed joint-space narrowing, and twelve of the fifteen had progression of degenerative joint disease. Reoperation was required in 85% of the patients. Additional work is needed to determine whether these transplants are truly achieving the desired results.
What is clear with meniscal transplantation is that accurate sizing of the grafts is paramount. A cadaver study defined the degree of acceptable mismatch as <10% of the original meniscus size23. Oversized grafts led to greater forces across the articular cartilage, whereas undersized grafts resulted in greater forces across the meniscus itself. Therefore, inappropriate graft-sizing may result in subsequent degenerative changes or failure of the graft.
Cartilage
Several techniques are available to address full-thickness focal chondral defects in the knee. These range from marrow-stimulation techniques, such as microfracture, to cartilage restorative procedures, such as osteochondral transfer and autologous chondrocyte implantation. Imaging studies such as magnetic resonance imaging often underestimate the extent of these lesions.
Marrow-stimulation techniques produce fibrocartilage, which is known to be less durable than true hyaline articular cartilage is. The results of these procedures may therefore decrease over time as the fibrocartilage degrades. This phenomenon is reflected in the literature. A study of high-impact athletes who were managed with microfracture demonstrated that only 66% of the patients had a good to excellent result after a minimum duration of follow-up of two years24. In addition, 47% of these athletes had an initial improvement but then had a subsequent decline in their clinical scores, even within this short follow-up period. Only 57% of the patients were able to return to their preoperative level of athletic involvement. On the basis of these data, the temptation is to reserve microfracture for older, sedentary patients. Other studies, however, have shown that the results of microfracture are better in patients younger than forty years of age. Therefore, the ideal patient is likely one who is younger than forty years of age with a small focal defect and a low activity level. Nevertheless, microfracture continues to be performed in many high-level athletes, often with good results, at least in the short term.
Osteochondral "plug" transfer is another commonly utilized option and may be more durable over the long term as it fills the lesion with hyaline cartilage rather than fibrocartilage. A practical issue that has been addressed in the recent literature is the concern about chondrocyte damage with impaction of these grafts. A cadaver study demonstrated that typical insertion forces resulted in chondrocyte death through apoptosis25. The effect was most pronounced in the superficial zone, and it may ultimately compromise the function of these grafts. This concept should be considered when inserting osteochondral grafts. Improvements in equipment and technique may ultimately reduce this risk.
A final option for the treatment of focal chondral defects is autologous chondrocyte implantation. Graft hypertrophy has been an area of clinical concern. A recent study of sixty-three patients demonstrated no cases of symptomatic graft hypertrophy in association with the use of a technique of covering the chondrocyte suspension with a type I/III collagen membrane as opposed to using the standard periosteal patch technique26. A newer technique of implanting the chondrocytes on a biodegradable scaffold without the need for a covering patch also has been developed. While not yet approved for use in the United States, this method simplifies the implantation technique and has shown good early results. A study from Italy involving the use of a hyaluronan-based scaffold demonstrated that 71% of the patients had near-normal cartilage on magnetic resonance imaging at two years of follow-up27. Second-look arthroscopy revealed near-normal surface characteristics, and the results of biopsies were consistent with hyaline-like cartilage. The patients also had significant improvement in terms of subjective symptoms.
Osteochondritis dissecans is another common articular cartilage condition that is encountered in the knee. The lesions are defined by their size, depth, and stability and are best assessed on magnetic resonance images. The results of a novel technique for the treatment of these lesions have been reviewed. The technique involves the use of autogenous osteochondral grafts for arthroscopic fixation. Two separate studies revealed healing of the lesions with incorporation of the grafts in all patients. This technique appears to provide a very effective alternative to traditional fixation of osteochondritis dissecans fragments.
Patellofemoral Articulation
The treatment of patellar instability continues to be an area of controversy, particularly after acute primary patellar dislocation. It is now well known that the medial patellofemoral ligament is the primary restraint to lateral patellar instability. On the basis of this anatomic patellar restraint, both primary repairs and various techniques of medial patellofemoral ligament reconstruction have been described and are in common use. The literature has yet to define the superiority of repair or reconstruction, and this will likely be an area of continued study. Regardless of the technique used, care must be taken to avoid overtensioning the ligament or placing it in a nonanatomic position. A cadaver study demonstrated that either of these technical errors results in overloading the medial patellar facet, which could subsequently result in progressive arthrosis and pain28.
Another issue that has been commonly explored in the recent literature is the use of arthroscopic lateral release with or without medial plication procedures for the treatment of recurrent patellar instability. Multiple studies have shown improved outcomes in association with the use of a lateral release combined with medial plication or even medial reefing alone as opposed to an isolated lateral release. Isolated lateral release results in significantly higher rates of recurrent instability, again highlighting the importance of the medial structures in patellar stability. Isolated lateral release may be best reserved for patients with a tight lateral retinaculum and patellar tilt as opposed to instability.
Another study of interest examined the effect of patella alta on knee joint kinematics29. Patients with patella alta were documented to have greater lateral displacement and tilt as well as decreased contact area as compared with a control group. These findings confirm the concept of patella alta as a risk factor for patellar instability. Other known risk factors for patellar instability include trochlear dysplasia, lower extremity malalignment with an increased Q angle, and systemic hyperlaxity. These patient characteristics should all be considered prior to determining the optimal treatment method for patellar instability.
Rotator Cuff
Issues surrounding the rotator cuff as well as shoulder instability continue to dominate research efforts related to the shoulder. Conditions of the rotator cuff are perhaps the most common shoulder afflictions seen by the orthopaedist. Therefore, we continue to strive to determine the best possible rotator cuff repair technique available. Open or mini-open repairs have long been considered to be the gold standard, with historically good results. Subsequent studies have shown improving results in association with arthroscopic techniques, and arthroscopic repairs are now generally considered equivalent to open repairs. Two studies in the recent literature confirmed this concept. Both studies demonstrated no difference in the clinical or structural outcomes of arthroscopic as opposed to mini-open repair, with a trend toward better results in association with arthroscopic repair. What is clear is that good results are achievable with both open and arthroscopic techniques.
A topic that has received much attention in the past couple of years is the concept of double-row repair. Multiple biomechanical studies have compared double-row with single-row fixation. A cadaver study demonstrated decreased gap formation under static loading and improved load to failure in association with double-row repair30. Another study demonstrated that, after single-row repair, 52.7% of the rotator cuff footprint remained uncovered31. After double-row repair, the entire footprint was covered, with no residual uncovered deficits. By enhancing footprint coverage, the surface area available for healing of the rotator cuff to the native bone bed is maximized. So-called transosseous-equivalent repairs also have gained popularity as a double-row repair method. In this technique, suture limbs from the medial row are secured laterally to bridge and compress the rotator cuff over the footprint. It has been proposed that this technique produces forces in the rotator cuff that are equivalent to those seen in association with traditional open transosseous suture-bridge techniques.
Whether or not the superior biomechanical properties of double-row fixation translate into improved clinical results is still being determined. In a prospective trial with a two-year follow-up period, patients were randomized to either single or double-row suture anchor repair32. Double-row fixation resulted in a mechanically superior construct with improved footprint coverage; however, these mechanical advantages did not translate into superior clinical performance. Other studies have demonstrated improved rotator cuff healing rates after double-row fixation. However, it is known that many patients demonstrate clinical improvement despite recurrent tears. This has been reflected in the current literature as well, with some studies showing improved clinical outcomes in association with double-row repairs and other studies showing equivalent clinical outcomes despite a lower rate of retears. The rate of retears associated with double-row fixation remains dependent on the size of the original cuff tear. One study demonstrated an overall retear rate of 17% in association with double-row fixation33. Small-to-medium tears had a retear rate of only 5%, whereas large and massive tears had a retear rate of 40%.
Another area of interest related to rotator cuff pathology is the concept of muscle atrophy and fatty infiltration. Advanced fatty infiltration inhibits successful repair attempts. Fatty infiltration is most commonly graded with a staging system developed by Goutallier and colleagues. While it was once thought that fatty infiltration could improve after cuff repair as a result of retensioning of the musculotendinous unit, this concept has been refuted in the recent literature. In fact, several studies have shown fatty infiltration and muscle atrophy to be irreversible after rotator cuff repair, resulting in inferior clinical results. Fatty infiltration of the infraspinatus may even continue to progress despite an intact repair. One study of thirty-eight patients confirmed that successful repairs did not lead to improvement or reversal of the muscle degeneration after one year of follow-up; however, intact cuffs revealed minimal progression over time34. In contrast, failed repairs demonstrated significant worsening of the muscle atrophy and fatty infiltration over time. These data reinforce the concept of repairing rotator cuff tears prior to substantial muscle deterioration in order to optimize outcomes. Of note, one study demonstrated clinical improvement in 86% of patients with advanced grade-3 or 4 fatty degeneration after cuff repair35. Ultimately, treatment recommendations must be individualized for each patient after thorough discussion. Younger patients with large tears and muscle degeneration often warrant attempts at repair with the knowledge that the outcome may be less than ideal.
Acromioclavicular Joint and Subacromial Space
The need for concomitant subacromial decompression with rotator cuff repair continues to be debated. Proponents of the procedure believe that it is necessary to prevent impingement of the rotator cuff. Others believe that impingement is not a contributing factor to cuff pathology and therefore believe subacromial decompression to be unnecessary. In a recent level-I study, patients were randomized to cuff repair with and without subacromial decompression36. The results showed that subacromial decompression had no influence on the clinical outcome at the time of short-term (two-year) follow-up. The utilization of subacromial decompression likely will continue to be determined by surgeon preference, with good results in either scenario.
Isolated conditions of the acromioclavicular joint are also common. In the athletic population, osteolysis of the distal part of the clavicle has been classically described in weight-lifters but certainly may affect other individuals as well. In addition, isolated arthrosis of the acromioclavicular joint may be a sequela of the common acromioclavicular separation. Distal clavicular resection is a reliable treatment method for these patients. Both open and arthroscopic techniques have been associated with good results. Regarding arthroscopic resections, a direct superior or indirect subacromial approach may be used. A recent study comparing these arthroscopic techniques in an athletic population demonstrated excellent clinical results in association with both techniques at the time of the two-year follow-up37. The direct superior approach allowed an earlier return to sports than the indirect subacromial approach did (mean, twenty-one days compared with forty-two days). Radiographs revealed an equivalent resection in both groups.
Biceps Tendon
Tendinopathy, tearing, and instability of the long head of the biceps tendon are common afflictions of the shoulder joint. These conditions were often overlooked in the past and likely accounted for persistent pain in a substantial subset of patients. The biceps tendon is often involved in association with disorders of the rotator cuff and should be addressed at the time of operative intervention. Instability of the biceps tendon may be associated with a tear of the subscapularis or may occur as an isolated phenomenon. Similarly, tendinopathy and tearing of the biceps may occur in isolation or in association with rotator cuff disease. Management options for the biceps tendon include tenotomy and a variety of tenodesis techniques.
In patients with massive irreparable rotator cuff tears, isolated biceps tenotomy or tenodesis may result in substantial symptomatic improvement. A recent study comparing tenotomy and tenodesis in this setting demonstrated similar clinical results in association with the two techniques38. Overall, 78% of patients were satisfied with the procedure. A "Popeye" deformity was present in 62% of the patients managed with tenotomy; however, none of these patients were reportedly concerned by it. Other studies have also demonstrated good results in association with débridement of irreparable rotator cuff tears and tenotomy or tenodesis of the long head of the biceps. Although not presented in the recent literature, we have adopted the use of subpectoral biceps tenodesis with good results.
Glenoid Labrum
Shoulder instability is another area in which research efforts have flourished. Some controversy still exists with regard to the most appropriate method for the treatment of acute, traumatic, anterior shoulder dislocations. It is well established that young male patients in particular are at the highest risk of recurrent instability. Several excellent articles in the recent literature have addressed the natural history and risk of recurrent instability and have compared nonoperative with operative interventions. The first study evaluated a prospective cohort of 252 patients ranging from fifteen to thirty-five years of age who had sustained an anterior glenohumeral dislocation and were managed with sling immobilization followed by a rehabilitation program39. Recurrent instability developed in 55.7% of the patients within the first two years, and this rate increased to 66.8% by the fifth year. A second study of 131 patients who were followed for four years after acute traumatic anterior shoulder dislocation demonstrated recurrent instability in forty-three patients (33%), thirty-nine of whom were under the age of forty years40. In addition, thirty-seven of these thirty-nine patients participated in collision sports or required use of the arm above the chest level in their occupation. In this high-risk group, approximately half of the patients ultimately underwent surgical stabilization. Patients with recurrent instability who chose not to undergo surgery had worse outcome scores. Older patients were more likely to require a rotator cuff repair than a Bankart repair. In another study, seventy-six patients ranging from fifteen to thirty-nine years of age were randomized to either surgical repair or conservative management41. At the time of the two-year follow-up, the rate of recurrent instability was 56% following conservative treatment and only 3% following open surgical repair. At the time of the ten-year follow-up, 72% of the patients in the surgical group had a good or excellent result whereas 75% of those in the conservative treatment group had an unsatisfactory result.
As with the rotator cuff, open surgical repairs, particularly the Bankart repair, traditionally have been considered the gold standard. Arthroscopic techniques have continued to evolve and improve to the point at which they are now typically considered to be equivalent to open repairs. Numerous articles in the recent literature have compared open with arthroscopic instability repairs. The results have been mixed. Some studies have continued to support open repairs as superior to arthroscopic techniques. A meta-analysis of eighteen separate studies demonstrated that, compared with open techniques, arthroscopic repairs were associated with a significantly higher incidence of recurrent instability, with fewer patients being able to return to work and sports activities42. However, the patients who were managed arthroscopically had significantly higher Rowe scores. In contrast, a prospective, randomized clinical trial of sixty-four patients demonstrated that open and arthroscopic stabilization were associated with equivalent clinical outcomes43. There were three failures overall, with two in the open repair group and one in the arthroscopic group. The operative time was shorter and the average loss of motion was less in association with the arthroscopic repairs. Several studies have also explored the failure rates of arthroscopic procedures without direct comparison to open procedures and have reported various rates of recurrent instability ranging from 5% to 38%. The durability of arthroscopic repairs has also been examined, with some reports showing maintenance of results and others demonstrating deterioration of results with long-term follow-up. Clearly, the debate continues. When performed diligently, both open and arthroscopic techniques can have excellent results. If recurrent instability does develop, the literature has shown both open and arthroscopic revision procedures to be effective solutions.
One concern with open repairs that has received increased attention is the issue of postoperative subscapularis dysfunction. The approach for open repair typically requires a release and subsequent repair of the subscapularis tendon. The result may be postoperative atrophy and fatty infiltration of the subscapularis, which in turn may compromise the clinical outcome. One comparative study demonstrated signs of subscapularis insufficiency in association with 70% of open repairs and 0% of arthroscopic repairs44. Overall clinical outcomes, however, were similar despite this finding. Another study with similar clinical outcomes demonstrated that the inferior part of the subscapularis was less affected by atrophy and fatty infiltration, which possibly accounts for the uncompromised clinical results45. When open repairs are performed, meticulous attention to detail must be given at the time of subscapularis repair to prevent complications and avoid potentially inferior outcomes.
As the trend moves further toward arthroscopic Bankart repair, techniques continue to be developed. Several reports on arthroscopic techniques were published in the recent literature. Fixation methods were frequently reviewed. Overall, suture anchor repairs were found to be superior to transglenoid suture repairs. Both traditional suture anchors and knotless suture anchors are widely used. The data on the newer knotless anchors have varied, with some studies showing results equivalent to standard suture anchor techniques and other studies demonstrating a significantly higher rate of recurrent instability. Additional long-term research is needed to fully document the effectiveness and durability of the knotless anchors in comparison with standard anchor constructs.
Superior labral anterior-posterior (SLAP) lesions are another common pathologic condition of the glenoid labrum. These lesions have received much less attention in the recent literature. Disruption of the biceps anchor is a key component in the treatment of these lesions. A cadaver study further defined the extent of labral disruption required to produce the so-called peel-back sign observed during shoulder arthroscopy46. The labrum was sequentially released beginning at the biceps anchor and then subsequently was repaired with a single suture placed at the 12:30 o'clock position. The study showed that detachment of the anchor alone did not result in a peel-back lesion; rather, disruption from the anchor to the 2 o'clock position was required. The subsequent single suture labral repair eliminated peel-back in all specimens. In general, mattress sutures have been shown to be superior to simple suture configurations in terms of the strength of repair47. In addition, mattress sutures move the knots away from the articular surface.
Femoroacetabular impingement remains the main area of focus on the hip in sports medicine. This condition has received increased attention in the past several years. Two main types of femoroacetabular impingement (the cam type and the pincer type) have been described. These two types of impingement are distinguished by their unique pathoanatomy. Cam-type impingement is characterized by a pistol-grip deformity of the femoral head-neck junction. The resulting convexity in this region abuts against the normal acetabulum with hip range of motion. In contrast, pincer-type impingement is characterized by increased retroversion of the acetabulum, causing abutment of the normal proximal part of the femur on the abnormal acetabulum. The result is pain, labral tears, articular cartilage injury, and ultimately a likely progression to degenerative hip disease. Open surgical dislocations initially were proposed as an effective treatment method and continue to be supported in the literature. A recent study examined the results of open osteochondroplasty for the treatment of cam-type femoroacetabular impingement after a mean duration of follow-up of three years48. There was significant improvement in terms of clinical symptoms, and no hip went on to osteonecrosis or required subsequent reconstructive surgery. However, six of the thirty-four patients were dissatisfied with the outcome.
Because of the potential morbidity of open procedures with surgical dislocation of the hip, arthroscopic treatment methods have been developed. The principles of treatment are similar to those of open methods, with osteoplasty being used to recontour the femoral head-neck junction for cam-type impingement and acetabular rim trimming being used for pincer-type impingement. Labral tears and chondral defects may also be addressed appropriately. The early results of these procedures appear to be promising; however, outcome and comparative studies have been sparse in the recent literature. Longer-term studies will also be required to determine if these procedures truly prevent the development of osteoarthritic hip disease.
Recent research efforts in the area of the foot and ankle have focused primarily on osteochondral lesions of the talus. These lesions are often a source of persistent pain following ankle sprains or healed ankle fractures. In general, anterolateral lesions are shallow, traumatic, and more likely to be displaced. Posteromedial lesions tend to be deeper, atraumatic, and nondisplaced. As our awareness of this condition has improved, treatment options have expanded, with many techniques being adopted from the treatment of chondral defects in the knee. Treatment options include arthroscopic débridement with chondroplasty, drilling or microfracture, osteochondral transfer, and even autologous chondrocyte implantation. In one study in which patients were randomized to chondroplasty, microfracture, or osteochondral autologous plug transfers, there were no significant clinical differences between the groups after an average duration of follow-up of fifty-three months49. Magnetic resonance imaging revealed incomplete fill and persistent edema after chondroplasty and microfracture and chondral gaps after osteochondral transfers.
An important concept in the ankle as well as in the knee is perpendicular access to the defect for drilling or microfracture and even more importantly for osteochondral transfer. Access to the talar dome can be limited, and malleolar osteotomies have been described to enhance access. However, the osteotomies themselves carry a substantial risk of morbidity, including nonunion. A recent cadaver study detailed the need for osteotomy to achieve perpendicular access to the talar dome50. The study showed that the majority of the talar dome can be accessed without an osteotomy. Only 17% of the medial aspect of the talar dome and 20% of the lateral aspect of the talar dome could not be accessed perpendicularly without an osteotomy. The central 15% of the talar dome could not be reached perpendicularly with any method. Therefore, while extensive lesions may still require osteotomy, most osteochondral lesions of the talus may be reached without creating this added morbidity.
Last, the harvest site for autologous plugs traditionally has been described in the knee. The concern, of course, is the creation of donor-site morbidity in a previously asymptomatic knee. This concern has been supported in the recent literature, with substantial knee symptoms being reported in a high percentage of patients and at times even affecting daily activities. Because of these concerns, attempts have been made to find available harvest sites within the existing operative field. Studies have shown that peripheral regions of the talar dome may indeed be a sufficient harvest site for the treatment of smaller lesions, thereby sparing the morbidity of an associated harvest site in the knee. In addition, it is possible that there may be subtle differences in the articular cartilage between the knee and ankle as these joints encounter different forces. It may therefore be preferable to obtain the grafts from a local site.
Medial ulnar collateral ligament injury is a potentially devastating injury in the throwing athlete. Reconstruction techniques and results are the focus of the literature. Jobe et al. first described a technique for ulnar collateral ligament reconstruction (later coined the "Tommy John procedure") in 1986. The original procedure had a success rate of 62.5% in throwing athletes and a complication rate of 31% secondary to ulnar nerve dysfunction. Altchek et al. subsequently described a modified technique, termed the docking procedure, utilizing a single humeral tunnel. One recent study51 documented a success rate of 90%, with a complication rate of only 3%. The ulnar nerve was transposed in only twenty-two of 100 cases, as opposed to all patients in the original Jobe series. Several other studies have also suggested improved biomechanical and clinical results of the docking procedure over the original Jobe procedure. Another study described a further modification of the docking procedure involving a four-strand palmaris longus graft in a group of twenty-five professional and collegiate baseball players, with a 92% rate of return to the preinjury level of competition52.
This is the area with perhaps the least focus in the sports medicine research arena. The literature is sparse as the majority of hand and wrist afflictions are treated by our hand-trained colleagues. Nevertheless, hand and wrist injuries are exceedingly common in the athletic population, and knowledge of the common injuries is warranted. The triangular fibrocartilage complex is an important stabilizer of the wrist and may be a frequent cause of pain and disability. The Palmer classification system is most commonly used but may not be fully inclusive of all lesions. With improved understanding of these injuries, arthroscopic treatment strategies have expanded. A recent study evaluated thirty-five patients after arthroscopic repair of triangular fibrocartilage complex injuries53. After an average duration of follow-up of thirty-nine months, 74% of the patients achieved good to excellent results, with reduction in pain, increased grip strength, and increased capacity to perform daily activities.
Catastrophic head and spine injuries in contact athletes continue to be the mainstay of research in this area. These are devastating injuries and warrant continued research efforts. One article described ninety-four incidents of severe football head injuries that had been reported to the National Center for Catastrophic Sport Injury Research over a thirteen-year period54. The incidence of catastrophic head injuries was found to be significantly higher in the high school population as compared with the collegiate population, with 0.67 injuries per 100,000 participants as compared with 0.21 injuries per 100,000 participants, respectively. Subdural hematoma was the most common diagnosis. The injury classification was unknown for four patients. Among the remaining ninety patients, there were eight deaths (prevalence, 9%), forty-six permanent neurologic injuries (51%), and thirty-six serious injuries with full recovery (40%). The most alarming finding of the study was that an unacceptably high percentage of athletes (39%) were playing with residual neurologic symptoms from a prior injury at the time of the catastrophic injury. This finding highlights the necessity of reinforcing to coaches, athletes, parents, and medical personnel that players with residual symptoms should not return to play until all symptoms have resolved. A number of algorithms are available to aid in assessing player readiness for return to play. Nevertheless, no universally accepted classification system exists for concussion, nor is there a single definitive treatment algorithm. Continued education in proper tackling techniques and acute management of athletes with head and spine injuries is important for reducing the incidence of these injuries.
The editorial staff of The Journal reviewed a large number of recently published evidence-based studies related to the musculoskeletal system. Over 100 medical journals were reviewed to identify these articles, which all have high-quality study design. In addition to the articles already cited in this Update, twelve articles were identified that were relevant to sports medicine. A list of those titles is appended to this review after the standard bibliography. We have provided a brief commentary about each of the articles to help guide your further reading, in an evidence-based fashion, in this subspecialty area.
Subspecialty certification in sports medicine is under the direction of the American Board of Orthopaedic Surgery (ABOS). The first subspecialty certification examination for sports medicine was held in November 2007. There were approximately 600 applicants. Requirements to apply for the examination include ABOS certification and an active sports medicine practice for a period of two years. Beginning in 2012, applicants must also have completed an Accreditation Council for Graduate Medical Education (ACGME)-accredited sports medicine fellowship. Ultimately, it is expected that recertification for this examination will count toward both general orthopaedic and subspecialty certification.
The application deadline for this year's examination is February 1, 2008, with examination fees due in May. Candidates will be mailed their scheduling/admission permits in July, and the examination will be administered in November at Prometric Technology Centers nationwide. More information is available on the ABOS website (). The second annual AOSSM/AAOS review course for subspecialty certification in orthopaedic sports medicine will be held August 1 through 3, 2008, in Chicago, Illinois. Applications for the 2009 examination will also be available online in August.
Sports medicine continues to be the largest subspecialty in orthopaedics, and sports medicine fellowships are the most popular fellowship choice. Seventy-two percent of sports medicine fellowships are currently ACGME accredited. Of the remaining twenty-seven non-accredited programs, most are seeking accreditation given the ABOS subspecialty certification requirements discussed above. The 2008-2009 fellowship class will be the first class requiring completion of an accredited program in order to sit for the ABOS subspecialty certification examination.
The main issue regarding sports medicine fellowships is the continued lack of a formal match process. The match dissolved in 2005 because of a lack of the required 75% rate of program participation. The AOSSM is actively working with the AOA (American Orthopaedic Association), the AAOS, and the ABOS to develop a universal match process for all orthopaedic subspecialties. In addition, the AOSSM introduced a "gentlemen's agreement" for the fellowship application process until a formal match is reinstituted. According to this agreement, interviews are to be conducted between December 1, 2007 and January 31, 2008. Applicants are not required to commit to a program prior to February 1, 2008, allowing them to complete all offered interviews before making a final decision. While there are no guarantees with this system, it will likely be adopted again next fellowship season if a formal match is not yet in place. A sample of the gentlemen's agreement and a list of participating fellowship programs are listed on the AOSSM website ().
The seventy-fifth annual meeting of the American Academy of Orthopaedic Surgeons will be held on March 5 through 9, 2008, in San Francisco, California, with Specialty Day being held on March 8, 2008. The annual meeting of the Arthroscopy Association of North America will be held on April 24 through 27, 2008, in Washington, DC. The annual meeting of the American Orthopaedic Society for Sports Medicine will be held on July 10 through 13, 2008, in Orlando, Florida.
Parker RD, Streem K, Schmitz L, Martineau PA; Marguerite Group. Efficacy of continuous intra-articular bupivacaine infusion for postoperative analgesia after anterior cruciate ligament reconstruction: a double-blinded, placebo-controlled, prospective, and randomized study. Am J Sports Med. 2007;35:531-6.
Patients were randomized to receive a continuous-infusion catheter with bupivacaine (study group), a catheter with saline solution (placebo group), or no catheter (control group) after anterior cruciate ligament reconstruction with a hamstring autograft. Control patients required increased narcotic use at forty-eight to seventy-two hours; however, there were no other significant differences among the groups with regard to pain or narcotic use through ninety-six hours postoperatively. This study, in addition to recent data suggesting potentially detrimental chondral effects of intra-articular bupivacaine, does not support this method of postoperative analgesia.
Hewett TE, Zazulak BT, Myer GD. Effects of the menstrual cycle on anterior cruciate ligament injury risk: a systematic review. Am J Sports Med. 2007;35:659-68.
This systematic review of the literature identified seven articles pertaining to the effect of the menstrual cycle on anterior cruciate ligament rupture in an effort to explain the increased incidence of anterior cruciate ligament tears in female individuals. The studies that were reviewed demonstrated a consistent association between the preovulatory phase of the menstrual cycle and an increased incidence of anterior cruciate ligament injuries.
Biau DJ, Tournoux C, Katsahian S, Schranz P, Nizard R. ACL reconstruction: a meta-analysis of functional scores. Clin Orthop Relat Res. 2007;458:180-7.
In this meta-analysis of fourteen studies (1263 patients), the results of anterior cruciate ligament reconstruction with use of patellar tendon or hamstring autografts were compared in terms of International Knee Documentation Committee scores and the return to the preinjury level of activity. No significant differences in outcome were identified between the two graft types. These data are consistent with the findings of the other studies presented in this update.
George MS, Huston LJ, Spindler KP. Endoscopic versus rear-entry anterior cruciate ligament reconstruction: a systematic review. Clin Orthop Relat Res. 2007;455:158-61.
Four prospective, randomized clinical trials comparing endoscopic single-incision and rear-entry double-incision anterior cruciate ligament reconstruction techniques were reviewed. Overall, similar outcomes were found between the two techniques. Differences included shorter operative times in the endoscopic group in two studies and a higher return to full activity in the rear-entry group in one study. Two studies demonstrated a higher percentage of patients with <3 mm of difference on KT-2000 arthrometry testing in association with the rear-entry technique. The other two studies demonstrated similar laxity outcomes. Excellent results are achievable with either technique.
Wright RW, Fetzer GB. Bracing after anterior cruciate ligament reconstruction: a systematic review. Clin Orthop Relat Res. 2007;455:162-8.
Twelve randomized controlled trials were systematically reviewed to determine if bracing after anterior cruciate ligament reconstruction has any bearing on outcomes. The evidence revealed no effect of bracing on pain, range of motion, graft stability, or protection from subsequent injury. On the basis of this review, the use of bracing after anterior cruciate ligament reconstruction cannot be supported.
Risberg MA, Holm I, Myklebust G, Engebretsen L. Neuromuscular training versus strength training during first 6 months after anterior cruciate ligament reconstruction: a randomized clinical trial. Phys Ther. 2007;87:737-50.
Seventy-four patients with anterior cruciate ligament reconstruction were randomized to one of two rehabilitation protocols. The first group (the NT group) was managed with six months of neuromuscular training. The other group (the ST group) was enrolled in a traditional strength-training program. At the time of the six-month follow-up, the NT group had significantly improved Cincinnati knee scores and visual analog scales scores for pain and function as compared with the ST group. It is recommended that neuromuscular training exercises be incorporated into standard rehabilitation protocols after anterior cruciate ligament reconstruction.
Charalambous CP, Tryfonidis M, Alvi F, Kumar R, Hirst P. Purely intra-articular versus general anesthesia for proposed arthroscopic partial meniscectomy of the knee: a randomized controlled trial. Arthroscopy. 2006;22:972-7.
In this level-I study, 107 patients undergoing knee arthroscopy for partial meniscectomy were randomized to either isolated intra-articular anesthesia or general anesthesia. The level of pain was significantly less in patients with intra-articular injections at six hours postoperatively, although it was similar between the two groups at twenty-four and forty-eight hours. The ease of the procedure was reported to be similar in both groups. Intra-articular anesthesia may be an effective alternative to general anesthesia for basic knee arthroscopy.
Lozano J, Ma CB, Cannon WD. All-inside meniscus repair: a systematic review. Clin Orthop Relat Res. 2007;455:134-41.
This systematic review evaluated the results of various all-inside meniscal repair devices. Failure rates ranged from 0% to 43.5%. No significant differences were found among the various meniscal repair devices, and failure rates did not differ on the basis of the duration of follow-up. The majority of the studies that were reviewed were case series (77%). Only 6.5% of the studies were prospective randomized trials. As such, no definite conclusions could be drawn with regard to the differences in clinical outcomes associated with the various devices. The results associated with any of these devices must ultimately be compared with the gold standard inside-out suture technique of meniscal repair.
Ryzewicz M, Peterson B, Siparsky PN, Bartz RL. The diagnosis of meniscus tears: the role of magnetic resonance imaging and clinical examination. Clin Orthop Relat Res. 2007;455:123-33.
A literature review identified thirty-two studies evaluating the role of clinical examination and magnetic resonance imaging in the diagnosis of meniscal tears. Overall, clinical evaluation by an experienced examiner identified patients with meniscal lesions as well as or better than magnetic resonance imaging did. The methods of clinical examination, however, are not fully elucidated and may vary among clinicians. It can be concluded that magnetic resonance imaging should be used in a confirmatory manner and that arthroscopy should be utilized for therapeutic, not diagnostic, purposes.
Stefancin JJ, Parker RD. First-time traumatic patellar dislocation: a systematic review. Clin Orthop Relat Res. 2007;455:93-101.
The initial treatment of primary traumatic patellar dislocations remains controversial. Seventy articles were included in this systematic review, with the primary focus being conservative as compared with operative intervention. The authors concluded that initial nonoperative management was recommended except in certain circumstances. These circumstances included the presence of an osteochondral fracture, substantial disruption of the medial patellar stabilizers, a laterally subluxated patella with normal alignment of the contralateral knee, recurrent dislocation, or failure of nonoperative treatment despite appropriate rehabilitation.
Swan KG Jr, Wolcott M. The athletic hernia: a systematic review. Clin Orthop Relat Res. 2007;455:78-87.
The medical, surgical, and orthopaedic literature was reviewed. The studies that were reviewed were primarily level-IV case series. The most common operative finding was a deficient posterior wall of the inguinal canal. Open and laparoscopic repair produced excellent results. A multidisciplinary approach to the diagnosis and treatment of this entity is recommended.
Silbernagel KG, Thomeé R, Eriksson BI, Karlsson J. Continued sports activity, using a pain-monitoring model, during rehabilitation in patients with Achilles tendinopathy: a randomized controlled study. Am J Sports Med. 2007;35:897-906.
Thirty-eight patients with Achilles tendinopathy were randomized to either an exercise training group or an active rest group. All patients underwent a similar rehabilitation program, with the exception that the patients in the exercise training group were allowed to continue Achilles tendon-loading activities, such as running and jumping, on the basis of a pain-monitoring model. Patients in the active rest group were restricted from these activities for six weeks. No significant differences were found between the groups at the time of the twelve-month follow-up. Patients in both groups demonstrated improvement from baseline. No negative effects were documented in association with the continuation of pain-monitored Achilles tendon-loading activities.
Maletis GB, Cameron SL, Tengan JJ, Burchette RJ. A prospective randomized study of anterior cruciate ligament reconstruction: a comparison of patellar tendon and quadruple-strand semitendinosus/gracilis tendons fixed with bioabsorbable interference screws. Am J Sports Med.2007;35:384-94.35384
2007
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Lidén M, Ejerhed L, Sernert N, Laxdal G, Kartus J. Patellar tendon or semitendinosus tendon autografts for anterior cruciate ligament reconstruction: a prospective, randomized study with a 7-year follow-up. Am J Sports Med.2007;35:740-8.35740
2007
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Sajovic M, Vengust V, Komadina R, Tavcar R, Skaza K. A prospective, randomized comparison of semitendinosus and gracilis tendon versus patellar tendon autografts for anterior cruciate ligament reconstruction: five-year follow-up. Am J Sports Med.2006;34:1933-40.341933
2006
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Keays SL, Bullock-Saxton JE, Keays AC, Newcombe PA, Bullock MI. A 6-year follow-up of the effect of graft site on strength, stability, range of motion, function, and joint degeneration after anterior cruciate ligament reconstruction: patellar tendon versus semitendinosus and gracilis tendon graft. Am J Sports Med.2007;35:729-39.35729
2007
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de Jong SN, van Caspel DR, van Haeff MJ, Saris DB. Functional assessment and muscle strength before and after reconstruction of chronic anterior cruciate ligament lesions. Arthroscopy.2007;23:21-8,28.e1-3.2321
2007
Palmieri-Smith RM, Kreinbrink J, Ashton-Miller JA, Wojtys EM. Quadriceps inhibition induced by an experimental knee joint effusion affects knee joint mechanics during a single-legged drop landing. Am J Sports Med.2007;35:1269-75.351269
2007
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Singhal MC, Gardiner JR, Johnson DL. Failure of primary anterior cruciate ligament surgery using anterior tibialis allograft. Arthroscopy.2007;23:469-75.23469
2007
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Laxdal G, Kartus J, Eriksson BI, Faxén E, Sernert N, Karlsson J. Biodegradable and metallic interference screws in anterior cruciate ligament reconstruction surgery using hamstring tendon grafts: prospective randomized study of radiographic results and clinical outcome. Am J Sports Med.2006;34:1574-80.341574
2006
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Tecklenburg K, Burkart P, Hoser C, Rieger M, Fink C. Prospective evaluation of patellar tendon graft fixation in anterior cruciate ligament reconstruction comparing composite bioabsorbable and allograft interference screws. Arthroscopy.2006;22:993-9.22993
2006
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Muneta T, Koga H, Mochizuki T, Ju YJ, Hara K, Nimura A, Yagishita K, Sekiya I. A prospective randomized study of 4-strand semitendinosus tendon anterior cruciate ligament reconstruction comparing single-bundle and double-bundle techniques. Arthroscopy.2007;23:618-28.23618
2007
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Asagumo H, Kimura M, Kobayashi Y, Taki M, Takagishi K. Anatomic reconstruction of the anterior cruciate ligament using double-bundle hamstring tendons: surgical techniques, clinical outcomes, and complications. Arthroscopy.2007;23:602-9.23602
2007
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Buoncristiani AM, Tjoumakaris FP, Starman JS, Ferretti M, Fu FH. Anatomic double-bundle anterior cruciate ligament reconstruction. Arthroscopy.2006;22:1000-6.221000
2006
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Wright RW, Dunn WR, Amendola A, Andrish JT, Bergfeld J, Kaeding CC, Marx RG, McCarty EC, Parker RD, Wolcott M, Wolf BR, Spindler KP. Risk of tearing the intact anterior cruciate ligament in the contralateral knee and rupturing the anterior cruciate ligament graft during the first 2 years after anterior cruciate ligament reconstruction: a prospective MOON cohort study. Am J Sports Med.2007;35:1131-4.351131
2007
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Carson EW, Deng XH, Allen A, Wickiewicz T, Warren RF. Evaluation of in situ graft forces of a 2-bundle tibial inlay posterior cruciate ligament reconstruction at various flexion angles. Arthroscopy.2007;23:488-95.23488
2007
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Markolf KL, Feeley BT, Tejwani SG, Martin DE, McAllister DR. Changes in knee laxity and ligament force after sectioning the posteromedial bundle of the posterior cruciate ligament. Arthroscopy.2006;22:1100-6.221100
2006
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Garofalo R, Jolles BM, Moretti B, Siegrist O. Double-bundle transtibial posterior cruciate ligament reconstruction with a tendon-patellar bone-semitendinosus tendon autograft: clinical results with a minimum of 2 years' follow-up. Arthroscopy.2006;22:1331-8.e1.221331
2006
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Shelbourne KD, Haro MS, Gray T. Knee dislocation with lateral side injury: results of an en masse surgical repair technique of the lateral side. Am J Sports Med.2007;35:1105-16.351105
2007
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Noyes FR, Barber-Westin SD. Posterolateral knee reconstruction with an anatomical bone-patellar tendon-bone reconstruction of the fibular collateral ligament. Am J Sports Med.2007;35:259-73.35259
2007
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Zhao J, He Y, Wang J. Anatomical reconstruction of knee posterolateral complex with the tendon of the long head of the biceps femoris. Am J Sports Med.2006;34:1615-22.341615
2006
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Bryant D, Dill J, Litchfield R, Amendola A, Giffin R, Fowler P, Kirkley A. Effectiveness of bioabsorbable arrows compared with inside-out suturing for vertical, reparable meniscal lesions: a randomized clinical trial. Am J Sports Med.2007;35:889-96.35889
2007
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Barber FA, Coons DA, Ruiz-Suarez M. Meniscal repair with the RapidLoc meniscal repair device. Arthroscopy.2006;22:962-6.22962
2006
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Hommen JP, Applegate GR, Del Pizzo W. Meniscus allograft transplantation: ten-year results of cryopreserved allografts. Arthroscopy.2007;23:388-93.23388
2007
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Dienst M, Greis PE, Ellis BJ, Bachus KN, Burks RT. Effect of lateral meniscal allograft sizing on contact mechanics of the lateral tibial plateau: an experimental study in human cadaveric knee joints. Am J Sports Med.2007;35:34-42.3534
2007
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Mithoefer K, Williams RJ 3rd, Warren RF, Wickiewicz TL, Marx RG. High-impact athletics after knee articular cartilage repair: a prospective evaluation of the microfracture technique. Am J Sports Med.2006;34:1413-8.341413
2006
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Borazjani BH, Chen AC, Bae WC, Patil S, Sah RL, Firestein GS, Bugbee WD. Effect of impact on chondrocyte viability during insertion of human osteochondral grafts. J Bone Joint Surg Am.2006;88:1934-43.881934
2006
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Steinwachs M, Kreuz PC. Autologous chondrocyte implantation in chondral defects of the knee with a type I/III collagen membrane: a prospective study with a 3-year follow-up. Arthroscopy.2007;23:381-7.23381
2007
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Gobbi A, Kon E, Berruto M, Francisco R, Filardo G, Marcacci M. Patellofemoral full-thickness chondral defects treated with Hyalograft-C: a clinical, arthroscopic, and histologic review. Am J Sports Med.2006;34:1763-73.341763
2006
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Elias JJ, Cosgarea AJ. Technical errors during medial patellofemoral ligament reconstruction could overload medial patellofemoral cartilage: a computational analysis. Am J Sports Med.2006;34:1478-85.341478
2006
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Ward SR, Terk MR, Powers CM. Patella alta: association with patellofemoral alignment and changes in contact area during weight-bearing. J Bone Joint Surg Am.2007;89:1749-55.891749
2007
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Smith CD, Alexander S, Hill AM, Huijsmans PE, Bull AM, Amis AA, De Beer JF, Wallace AL. A biomechanical comparison of single and double-row fixation in arthroscopic rotator cuff repair. J Bone Joint Surg Am.2006;88:2425-31.882425
2006
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Brady PC, Arrigoni P, Burkhart SS. Evaluation of residual rotator cuff defects after in vivo single- versus double-row rotator cuff repairs. Arthroscopy.2006;22:1070-5.221070
2006
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Franceschi F, Ruzzini L, Longo UG, Martina FM, Zobel BB, Maffulli N, Denaro V. Equivalent clinical results of arthroscopic single-row and double-row suture anchor repair for rotator cuff tears: a randomized controlled trial. Am J Sports Med.2007;35:1254-60.351254
2007
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Sugaya H, Maeda K, Matsuki K, Moriishi J. Repair integrity and functional outcome after arthroscopic double-row rotator cuff repair. A prospective outcome study. J Bone Joint Surg Am.2007;89:953-60.89953
2007
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Gladstone JN, Bishop JY, Lo IK, Flatow EL. Fatty infiltration and atrophy of the rotator cuff do not improve after rotator cuff repair and correlate with poor functional outcome. Am J Sports Med.2007;35:719-28.35719
2007
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Burkhart SS, Barth JR, Richards DP, Zlatkin MB, Larsen M. Arthroscopic repair of massive rotator cuff tears with stage 3 and 4 fatty degeneration. Arthroscopy.2007;23:347-54.23347
2007
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Milano G, Grasso A, Salvatore M, Zarelli D, Deriu L, Fabbriciani C. Arthroscopic rotator cuff repair with and without subacromial decompression: a prospective randomized study. Arthroscopy.2007;23:81-8.2381
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Charron KM, Schepsis AA, Voloshin I. Arthroscopic distal clavicle resection in athletes: a prospective comparison of the direct and indirect approach. Am J Sports Med.2007;35:53-8.3553
2007
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Boileau P, Baqué F, Valerio L, Ahrens P, Chuinard C, Trojani C. Isolated arthroscopic biceps tenotomy or tenodesis improves symptoms in patients with massive irreparable rotator cuff tears. J Bone Joint Surg Am.2007;89:747-57.89747
2007
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Robinson CM, Howes J, Murdoch H, Will E, Graham C. Functional outcome and risk of recurrent instability after primary traumatic anterior shoulder dislocation in young patients. J Bone Joint Surg Am.2006;88:2326-36.882326
2006
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Sachs RA, Lin D, Stone ML, Paxton E, Kuney M. Can the need for future surgery for acute traumatic anterior shoulder dislocation be predicted? J Bone Joint Surg Am.2007;89:1665-74.891665
2007
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Jakobsen BW, Johannsen HV, Suder P, Søjbjerg JO. Primary repair versus conservative treatment of first-time traumatic anterior dislocation of the shoulder: a randomized study with 10-year follow-up. Arthroscopy.2007;23:118-23.23118
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Lenters TR, Franta AK, Wolf FM, Leopold SS, Matsen FA 3rd. Arthroscopic compared with open repairs for recurrent anterior shoulder instability. A systematic review and meta-analysis of the literature. J Bone Joint Surg Am.2007;89:244-54.89244
2007
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Bottoni CR, Smith EL, Berkowitz MJ, Towle RB, Moore JH. Arthroscopic versus open shoulder stabilization for recurrent anterior instability: a prospective randomized clinical trial. Am J Sports Med.2006;34:1730-7.341730
2006
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Scheibel M, Nikulka C, Dick A, Schroeder RJ, Popp AG, Haas NP. Structural integrity and clinical function of the subscapularis musculotendinous unit after arthroscopic and open shoulder stabilization. Am J Sports Med.2007;35:1153-61.351153
2007
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Scheibel M, Tsynman A, Magosch P, Schroeder RJ, Habermeyer P. Postoperative subscapularis muscle insufficiency after primary and revision open shoulder stabilization. Am J Sports Med.2006;34:1586-93.341586
2006
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Seneviratne A, Montgomery K, Bevilacqua B, Zikria B. Quantifying the extent of a type II SLAP lesion required to cause peel-back of the glenoid labrum—a cadaveric study. Arthroscopy.2006;22:1163-7.e1-6.221163
2006
Domb BG, Ehteshami JR, Shindle MK, Gulotta L, Zoghi-Moghadam M, MacGillivray JD, Altchek DW. Biomechanical comparison of 3 suture anchor configurations for repair of type II SLAP lesions. Arthroscopy.2007;23:135-40.23135
2007
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Beaulé PE, Le Duff MJ, Zaragoza E. Quality of life following femoral head-neck osteochondroplasty for femoroacetabular impingement. J Bone Joint Surg Am.2007;89:773-9.89773
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