The Journal of Bone & Joint Surgery Current Issue

Recent Advances in the Prevention and Management of Complications Associated with Routine Lumbar Spine Surgery

Jenis LG, Hsu WK, O’Brien J, et al. — Wed, 15 May 2013 00:00:00 GMT

In 2009, more than 448,000 patients underwent spinal arthrodesis in the United States¹. Complications have been reported to range from 4% to 19%, depending on the nature of the spine surgery². Some of the most commonly encountered, yet highly preventable, complications are surgical site infection and hemorrhagic and/or thromboembolic complications. With the above in mind, prevention of infection should be a paramount concern for all spine surgeons. Recent areas of focus have been on eradication of normal bacterial skin flora prior to surgery via skin antisepsis and nasal decolonization, application of topical antibiotics, and perioperative glycemic management, as well as insights into sterile processing.

Adverse Local Tissue Reaction Arising from Corrosion at the Femoral Neck-Body Junction in a Dual-Taper Stem with a Cobalt-Chromium Modular Neck

Cooper H, Urban RM, Wixson RL, et al. — Wed, 15 May 2013 00:00:00 GMT

Background:

Femoral stems with dual-taper modularity were introduced to allow additional options for hip-center restoration independent of femoral fixation in total hip arthroplasty. Despite the increasing availability and use of these femoral stems, concerns exist about potential complications arising from the modular neck-body junction.

Methods:

This was a multicenter retrospective case series of twelve hips (eleven patients) with adverse local tissue reactions secondary to corrosion at the modular neck-body junction. The cohort included eight women and three men who together had an average age of 60.1 years (range, forty-three to seventy-seven years); all hips were implanted with a titanium-alloy stem and cobalt-chromium-alloy neck. Patients presented with new-onset and increasing pain at a mean of 7.9 months (range, five to thirteen months) following total hip arthroplasty. After serum metal-ion studies and metal artifact reduction sequence (MARS) magnetic resonance imaging (MRI) revealed abnormal results, the patients underwent hip revision at a mean of 15.2 months (range, ten to twenty-three months). Tissue specimens were examined by a single histopathologist, and the retrieved implants were studied with use of light and scanning electron microscopy.

Results:

Serum metal levels demonstrated greater elevation of cobalt (mean, 6.0 ng/mL) than chromium (mean, 0.6 ng/mL) or titanium (mean, 3.4 ng/mL). MRI with use of MARS demonstrated adverse tissue reactions in eight of nine patients in which it was performed. All hips showed large soft-tissue masses and surrounding tissue damage with visible corrosion at the modular femoral neck-body junction. Available histology demonstrated large areas of tissue necrosis in seven of ten cases, while remaining viable capsular tissue showed a dense lymphocytic infiltrate. Microscopic analysis was consistent with fretting and crevice corrosion at the modular neck-body interface.

Conclusions:

Corrosion at the modular neck-body junction in dual-tapered stems with a modular cobalt-chromium-alloy femoral neck can lead to release of metal ions and debris resulting in local soft-tissue destruction. Adverse local tissue reaction should be considered as a potential cause for new-onset pain in patients with these components, and early revision should be considered given the potentially destructive nature of these reactions. A workup including serologic studies (erythrocyte sedimentation rate and C-reactive protein), serum metal levels, and MARS MRI can be helpful in establishing this diagnosis.

Level of Evidence:

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Comparison of Functional Outcomes Following Bridge Synostosis with Non-Bone-Bridging Transtibial Combat-Related Amputations

Keeling CJ, Shawen LB, Forsberg CA, et al. — Wed, 15 May 2013 00:00:00 GMT

Background:

The prevalence of penetrating wartime trauma to the extremities has increased in recent military conflicts. Substantial controversy remains in the orthopaedic and prosthetic literature regarding which surgical technique should be performed to obtain the most functional transtibial amputation. We compared self-reported functional outcomes associated with two surgical techniques for transtibial amputation: bridge synostosis (modified Ertl) and non-bone-bridging (modified Burgess).

Methods:

A review of the prospective military amputee database was performed to identify patients who had undergone transtibial amputation between June 2003 and December 2010 at three military institutions receiving the majority of casualties from the most recent military conflicts; two of those institutions, Walter Reed Army Medical Center and National Naval Medical Center, have since been consolidated. Short Form-36, Prosthesis Evaluation Questionnaire, and functional data questions were completed by twenty-seven modified Ertl and thirty-eight modified Burgess isolated transtibial amputees.

Results:

The average duration of follow-up after amputation (and standard deviation) was 32 ± 22.7 months, which was similar between groups. Residual limb length was significantly longer in the modified Ertl cohort by 2.5 cm (p < 0.005), and significantly more modified Ertl patients had delayed amputations (p < 0.005). There were no significant differences between groups with regard to any of the Short Form-36 domains or Prosthesis Evaluation Questionnaire subsections.

Conclusions:

The modified Ertl and Burgess techniques offer similar functional outcomes in the young, active-duty military population managed with transtibial amputation.

Level of Evidence:

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Comparison of Functional Outcomes of Reverse Shoulder Arthroplasty with Those of Hemiarthroplasty in the Treatment of Cuff-Tear Arthropathy A Matched-Pair Analysis

Young SW, Zhu M, Walker CG, et al. — Wed, 15 May 2013 00:00:00 GMT

Background:

Rotator cuff-tear arthropathy has traditionally represented a challenge to the shoulder arthroplasty surgeon. The poor results of conventional total shoulder arthroplasty in rotator-cuff-deficient shoulders due to glenoid component loosening have led to hemiarthroplasty being the traditional preferred surgical option. Recently, reverse total shoulder arthroplasty has gained increasing popularity because of a clinical perception of an improved functional outcome, despite the lack of comparative data. The aim of this study was to compare the early functional results of hemiarthroplasty with those of reverse shoulder arthroplasty in the management of cuff-tear arthropathy.

Methods:

The results of 102 primary hemiarthroplasties for rotator cuff-tear arthropathy were compared with those of 102 reverse shoulder arthroplasties performed for the same diagnosis. Patients were identified from the New Zealand Joint Registry and matched for age, sex, and American Society of Anesthesiologists (ASA) scores. Oxford Shoulder Scores (OSS) collected at six months postoperatively as well as mortality and revision rates were compared between the two groups.

Results:

There were fifty-one men and fifty-one women in each group, with a mean age of 71.6 years in the hemiarthroplasty group and 72.6 years in the reverse shoulder arthroplasty group. The mean OSS at six months was 31.1 in the hemiarthroplasty group and 37.5 in the reverse shoulder arthroplasty group. At the time of follow-up, there were nine revisions in the hemiarthroplasty group and five in the reverse shoulder arthroplasty group. No difference in mortality rate was seen between the two groups.

Conclusions:

In this unselected population with rotator cuff-tear arthropathy, controlled for age, sex, and ASA score, reverse shoulder arthroplasty resulted in a functional outcome that was superior to that of hemiarthroplasty. Longer-term follow-up is needed to confirm these findings.

Level of Evidence:

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Do Oblique Views Add Value in the Diagnosis of Spondylolysis in Adolescents?

Beck NA, Miller R, Baldwin K, et al. — Wed, 15 May 2013 00:00:00 GMT

Background:

Anteroposterior, lateral, and right and left oblique lumbar spine radiographs are often a standard part of the evaluation of children who are clinically suspected of having spondylolysis. Recent concerns regarding radiation exposure and costs have brought the value of oblique radiographs into question. The purpose of the present study was to determine the diagnostic value of oblique views in the diagnosis of spondylolysis.

Methods:

Radiographs of fifty adolescents with L5 spondylolysis without spondylolisthesis and fifty controls were retrospectively reviewed. All controls were confirmed not to have spondylolysis on the basis of computed tomographic scanning, magnetic resonance imaging, or bone scanning. Anteroposterior, lateral, and right and left oblique radiographs of the lumbar spine were arranged into two sets of slides: one showing four views (anteroposterior, lateral, right oblique, and left oblique) and one showing two views (anteroposterior and lateral only). The slides were randomly presented to four pediatric spine surgeons for diagnosis, with four-view slides being presented first, followed by two-view slides. The slides for twenty random patients were later reanalyzed in order to calculate of intra-rater agreement. A power analysis demonstrated that this study was adequately powered. Inter-rater and intra-rater agreement were assessed on the basis of the percentage of overall agreement and intraclass correlation coefficients (ICCs). PCXMC software was used to generate effective radiation doses. Study charges were determined from radiology billing data.

Results:

There was no significant difference in sensitivity and specificity between four-view and two-view radiographs in the diagnosis of spondylolysis. The sensitivity was 0.59 for two-view studies and 0.53 for four-view studies (p = 0.33). The specificity was 0.96 for two-view studies and 0.94 for four-view studies (p = 0.60). Inter-rater agreement, intra-rater agreement, and agreement with gold-standard ICC values were in the moderate range and also demonstrated no significant differences. Percent overall agreement was 78% for four-view studies and 82% for two-view studies. The radiation effective dose was 1.26 mSv for four-view studies and 0.72 mSv for two-view studies (difference, 0.54 mSv). The charge for four-view studies was $145 more than that for two-view studies.

Conclusions:

There is no difference in sensitivity and specificity between four-view and two-view studies. Although oblique views have long been considered standard practice by some, our data could not identify a diagnostic benefit that might outweigh the additional cost and radiation exposure.

Level of Evidence:

Diagnostic Level I. See Instructions for Authors for a complete description of levels of evidence.

Evaluating the Extent of Clinical Uncertainty Among Treatment Options for Patients with Early-Onset Scoliosis

Corona J, Miller DJ, Downs J, et al. — Wed, 15 May 2013 00:00:00 GMT

Background:

Literature guiding the management of early-onset scoliosis consists primarily of studies with a low level of evidence. Evaluation of clinical equipoise (i.e., when there is no known superiority among treatment modalities) allows for prioritization of research efforts. The objective of this study was to evaluate areas of clinical uncertainty among pediatric spine surgeons regarding the treatment of early-onset scoliosis.

Methods:

Fourteen experienced pediatric spine surgeons participated in semistructured interviews to identify clinical variables that influence decision making in the treatment of early-onset scoliosis. A series of case scenarios of 315 patients with idiopathic and neuromuscular early-onset scoliosis was then developed to be representative of those encountered in clinical practice. Using an online survey, eleven surgeons selected their choice of eight treatment options for each case scenario. Associations between case characteristics and treatment choices were assessed with chi-square and logistic regression analysis. Participants then reviewed the areas of treatment uncertainty identified in the survey, nominated additional research questions of interest, and ranked their interest to further explore the identified research questions.

Results:

Collective equipoise was identified in numerous scenarios in the survey spanning a range of ages and magnitudes of scoliosis, and additional questions were identified during the nominal group technique. Areas that had the greatest clinical uncertainty included the management of patients who have finished treatment with a growing-rod, timing of rod-lengthening intervals, and indications for spine-based and rib-based proximal instrumentation anchors. The use of rib anchors compared with spine-based anchors was ranked highly for consideration in future clinical trials.

Conclusions:

Variability in decision making with regard to the optimum treatment of certain subsets of patients with early-onset scoliosis reflects gaps in the available evidence. Structured consensus methods identified priorities for higher levels of research in this area of scoliosis. Higher-level studies, including randomized trials, should focus on answering the questions highlighted in this report.

Heterotopic Ossification After Surgery for Fractures and Fracture-Dislocations Involving the Proximal Aspect of the Radius or Ulna

Foruria AM, Augustin S, Morrey BF, et al. — Wed, 15 May 2013 00:00:00 GMT

Background:

The objectives of this study were to (1) determine the prevalence of heterotopic ossification after surgery for fractures and fracture-dislocations involving the proximal aspect of the radius or ulna, (2) identify risk factors associated with the development of heterotopic ossification in these injuries, and (3) characterize the severity and location of the heterotopic ossification and the associated range of elbow motion.

Methods:

From 2004 to 2008, 142 elbow fractures and fracture-dislocations involving the proximal aspect of the radius or ulna were treated surgically at our institution. Records and radiographs of 130 elbows with adequate follow-up were retrospectively reviewed to identify cases of heterotopic ossification, characterize the ectopic bone, and analyze associated risk factors. The most frequent injuries included olecranon fractures, Monteggia fracture-dislocations, and various combinations of fractures of the radial head and coronoid with or without dislocation or subluxation.

Results:

Heterotopic bone was identified on the radiographs of forty-eight elbows (37%). Heterotopic ossification interfered with motion in twenty-six elbows (20%), and thirteen elbows (10%) underwent additional surgery to remove heterotopic bone with the goal of improving motion. Risk factors associated with the development of heterotopic ossification included elbow subluxation or dislocation at the time of presentation, an open fracture, a severe chest injury, and a delay in definitive surgical treatment. Ectopic bone was preferentially located at the origin of torn soft-tissue structures or around fracture sites, and it was particularly common around the posterior aspect of the ulna and the neck of the radius. Heterotopic ossification was classified on radiographs as hazy immature in twenty-two elbows, limited mature in eighteen, extensive mature in five, and a complete bone bridge in three. Heterotopic ossification was more common in patients with an associated distal humeral fracture, radial head and coronoid fractures with an associated elbow dislocation (terrible triad injury), and a transolecranon fracture-dislocation.

Conclusions:

Thirty-seven percent of elbows treated surgically for fractures involving the proximal aspect of the radius and/or ulna developed heterotopic ossification. In twenty percent of elbows, heterotopic ossification was associated with clinically relevant motion deficits. More severe heterotopic ossification was encountered in patients presenting with an associated distal humeral fracture, terrible triad injury, transolecranon fracture-dislocation, or Monteggia fracture-dislocation. Patients with an open injury, instability, severe chest trauma, or delay in definitive surgical treatment had a higher prevalence of heterotopic ossification.

Level of Evidence:

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Magnetic Resonance Imaging Findings in Symptomatic Versus Asymptomatic Subjects Following Metal-on-Metal Hip Resurfacing Arthroplasty

Nawabi DH, Hayter CL, Su EP, et al. — Wed, 15 May 2013 00:00:00 GMT

Background:

Although pseudotumors have been reported at the sites of well-functioning and painful metal-on-metal hip prostheses, there are no objective data on the magnitude of the adverse reaction. This observational study was performed to investigate the ability of modified magnetic resonance imaging (MRI) to detect and quantify adverse synovial responses in symptomatic and asymptomatic subjects following metal-on-metal hip resurfacing. We hypothesized that the magnitude of the synovial reactions would be greater in symptomatic patients.

Methods:

Sixty-nine patients (seventy-four hips) with hip resurfacing were divided into three groups: asymptomatic (twenty-two hips), symptomatic with a mechanical cause (twenty), and unexplained pain (thirty-two). The volume of synovitis was calculated on MRI for all patients.

Results:

Synovitis was detected in fifteen asymptomatic hips (68%), fifteen (75%) with symptoms with a mechanical causes, and twenty-five (78%) with unexplained pain. The mean volume (and standard deviation) of the synovitis in these groups was 5 ± 7 cm³, 10 ± 16 cm³, and 31 ± 47 cm³, respectively. The coefficient of repeatability between the examiners was 1.8 cm³ for measurement of synovitis. Of the thirteen subjects with revision arthroplasty, six had an adverse local tissue reaction. This subgroup had the highest volumes of synovitis on MRI.

Conclusions:

An adverse synovial reaction was detected on MRI in both symptomatic and asymptomatic subjects. We found a larger volume of synovitis in symptomatic patients; this increase reached significance only in the group with an adverse local tissue reaction. Synovial volume on MRI may be a valuable marker in the longitudinal assessment of asymptomatic patients with a metal-on-metal hip resurfacing and in identifying patients with adverse local tissue reaction.

Level of Evidence:

Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Magnetic Resonance Imaging of the Hand and Wrist: Techniques and Spectrum of Disease AAOS Exhibit Selection

Dewan AK, Chhabra A, Khanna A, et al. — Wed, 15 May 2013 00:00:00 GMT

Magnetic resonance imaging (MRI) is an excellent imaging modality for the evaluation of pathologic processes of the hand and wrist. MRI of the hand and wrist provides high-resolution imaging of osseous structures and soft-tissue structures (including ligaments, tendons, nerves, and muscles) through the use of multiple imaging techniques and pulse sequences. This article updates orthopaedic surgeons on current MRI techniques and illustrates the spectrum of hand and wrist disease detectable by MRI. We searched PubMed with use of the keywords “MRI” plus “hand” or “wrist” for studies less than five years old evaluating MRI techniques. On the basis of a review of the recently published literature and the authors’ experience, we define and describe the applications of the following: (1) conventional, non-gadolinium-enhanced MRI, (2) gadolinium-enhanced MRI, and (3) MR arthrography. We also describe the classic MRI appearance of lesions commonly evaluated by MRI, including occult fracture, triangular fibrocartilage complex injury, interosseous ligament injury, extrinsic carpal ligament injury, thumb ulnar collateral ligament injury, traumatic tendon injury, finger pulley injury, ulnar impaction syndrome, tendinopathy, Kienböck disease, posttraumatic scaphoid osteonecrosis, infection, inflammatory arthropathy, compression neuropathy, and various soft-tissue masses.

Modern Unicompartmental Knee Arthroplasty with Cement A Concise Follow-up, at a Mean of Twenty Years, of a Previous Report *

Argenson JA, Blanc G, Aubaniac J, et al. — Wed, 15 May 2013 00:00:00 GMT

Abstract:

We previously evaluated the three to ten-year results of 160 consecutive unicompartmental knee arthroplasties that had been performed by two surgeons in 147 patients with use of the cemented metal-backed Miller-Galante prosthesis. The average age of the patients at the time of the index procedure was sixty-six years. The purpose of the present study was to report the updated results of this series after a mean duration of follow-up of twenty years. Sixty-two patients (seventy knees) were living, and seven had been lost to follow-up. Eleven knees had undergone conversion to total knee arthroplasty, three had had an addition of a patellofemoral prosthesis, and five had had polyethylene exchange. Ten knees had had revision since the three to ten-year evaluation. The reasons for revision included progression of osteoarthritis in twelve knees, aseptic loosening (which had been absent at the three to ten-year evaluation) in two knees, and polyethylene wear (which was treated with liner exchange at an average of twelve years) in five knees. The average clinical and functional Knee Society scores were 91 and 88 points, respectively, at the time of the latest follow-up. The average flexion was 127° (range, 80° to 145°). We concluded that modern cemented metal-backed unicompartmental implants, evaluated at a mean of twenty years of follow-up in patients with osteoarthritis that was limited to one tibiofemoral compartment of the knee, provided durable pain relief and long-term restoration of knee function without compromising future conversion to conventional total knee arthroplasty.

Level of Evidence:

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Multilevel Surgery for Equinus Gait in Children with Spastic Diplegic Cerebral Palsy Medium-Term Follow-up with Gait Analysis

Firth GB, Passmore E, Sangeux M, et al. — Wed, 15 May 2013 00:00:00 GMT

Background:

In children with spastic diplegia, surgery for ankle equinus contracture is associated with a high prevalence of both overcorrection, which may result in a calcaneal deformity and crouch gait, and recurrent equinus contracture, which may require revision surgery. We sought to determine if conservative surgery for equinus gait, in the context of multilevel surgery, could result in the avoidance of overcorrection and crouch gait as well as an acceptable rate of recurrent equinus contracture at the time of medium-term follow-up.

Methods:

This was a retrospective, consecutive cohort study of children with spastic diplegia who had had surgery for equinus gait between 1996 and 2006. All children had distal gastrocnemius recession or differential gastrocnemius-soleus complex lengthening, on one or both sides, as part of single-event multilevel surgery. The primary outcome measures were the Gait Variable Scores (GVS) and Gait Profile Score (GPS) at two time points after surgery.

Results:

Forty children with spastic diplegia, Gross Motor Function Classification System (GMFCS) level II or III, were included in this study. There were twenty-five boys and fifteen girls. The mean age was ten years at the time of surgery and seventeen years at the time of final follow-up. The mean postoperative follow-up period was 7.5 years. The mean ankle GVS improved from 18.5° before surgery to 8.7° at the time of short-term follow-up (p < 0.005) and 7.8° at the time of medium-term follow-up. The equinus gait was successfully corrected in the majority of children, with a low rate of overcorrection (2.5%) and a high rate of recurrent equinus (35%), as determined by sagittal ankle kinematics. Mild recurrent equinus was usually well tolerated and conferred some advantages, including contributing to strong coupling at the knee and independence from using an ankle-foot orthosis.

Conclusions:

Surgical treatment for equinus gait in children with spastic diplegia was successful, at a mean of seven years, in the majority of cases when combined with multilevel surgery, orthoses, and rehabilitation. No patient developed crouch gait, and the rate of revision surgery for recurrent equinus was 12.5%.

Level of Evidence:

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Prospective Comparison of 1.5 and 3.0-T MRI for Evaluating the Knee Menisci and ACL

Van Dyck P, Vanhoenacker FM, Lambrecht V, et al. — Wed, 15 May 2013 00:00:00 GMT

Background:

MRI (magnetic resonance imaging) is widely used to diagnose meniscal pathology and ACL (anterior cruciate ligament) tears. Because of the enhanced signal-to-noise ratio and improved image quality at higher field strength, knee MRI equipment is shifting from 1.5 to 3.0 T. To date, objective evidence of improved diagnostic ability at 3.0 T is lacking. The purpose of this prospective study was to assess the accuracy of 1.5 and 3.0-T MRI of the knee, in the same individuals, for diagnosing meniscal pathology and ACL tears, utilizing arthroscopy as the reference standard.

Methods:

Two hundred patients underwent MRI of the knee at 1.5 and 3.0 T. All MRI examinations consisted of multiplanar turbo spin-echo sequences. One hundred patients underwent subsequent knee arthroscopy. Two blinded independent radiologists assessed all MRI studies to identify meniscal pathology and ACL tears. In patients with MRI results indicating the need for surgical treatment, the sensitivity and specificity of the 1.5 and 3.0-T protocols for detecting these lesions were determined, utilizing arthroscopy as the reference standard, and compared with use of the McNemar test. The kappa statistic for inter-reader agreement in the 200 patients was calculated.

Results:

For medial meniscal tears, the mean sensitivity and specificity for the two readers were 93% and 90%, respectively, at 1.5 T and 96% and 88%, respectively, at 3.0 T. For lateral meniscal tears, the mean sensitivity and specificity were 77% and 99%, respectively, at 1.5 T and 82% and 98%, respectively, at 3.0 T. For ACL tears, the mean sensitivity and specificity were 78% and 100%, respectively, at 1.5 T and 80% and 100%, respectively, at 3.0 T. None of the values for either reader differed significantly between the 1.5 and 3.0-T MRI protocols. Inter-reader agreement was almost perfect to perfect (kappa = 0.82 to 1.00).

Conclusions:

Routine use of a 3.0-T MRI protocol did not significantly improve accuracy for evaluating the knee menisci and ACL compared with a similar 1.5-T protocol.

Level of Evidence:

Diagnostic Level I. See Instructions for Authors for a complete description of levels of evidence.

The Effect of Immobilization on the Native and Repaired Tendon-to-Bone Interface

Hettrich CM, Gasinu SS, Beamer BS, et al. — Wed, 15 May 2013 00:00:00 GMT

Background:

Little is known of the cellular events that occur in native or repaired tendons as a result of immobilization after injury. To examine this issue, we compared (1) native tendons without immobilization, (2) native tendons with immobilization, and (3) surgically repaired tendons with immobilization.

Methods:

Eighty-one rats underwent either patellar tendon repair followed by immobilization or immobilization of the native tendon without repair. A custom external fixation device was used for immobilization. The tendon-bone insertion site was evaluated after two and four weeks of immobilization with use of histologic, radiographic, and biomechanical analyses.

Results:

Immobilization of the native tendon led to a significant decrease in the load to failure (p < 0.01) and stiffness (p < 0.05) compared with the native tendon at both two and four weeks. The repaired/immobilized group had a significantly lower load to failure at two weeks compared with the native/immobilized group (p < 0.05); however, by four weeks, the repaired group was significantly stronger (p < 0.01). Micro-computerized tomography demonstrated no significant differences in bone microstructure at two weeks but demonstrated increased bone mineral density and bone volume fraction in the repaired/immobilized group at four weeks. There was significantly more MMP-13 (matrix metalloproteinase-13) staining in the native/immobilized specimens compared with the native specimens at both time points (p < 0.01).

Conclusions:

Immobilization had a significant detrimental effect on the bone-tendon complex. At two weeks there was a significant decrease in the mechanical properties of the native tendon, but the immobilized, native tendon remained significantly stronger than the repaired and immobilized tendon. However, four weeks of immobilization led to a significant loss of strength of the bone-tendon complex in the native tendon, such that it was significantly weaker than the repaired and immobilized tendon. Surgeons who manage patients with immobilization should be aware of the changes at the bone-tendon complex.

Clinical Relevance:

Immobilization may have negative effects on the native bone-tendon complex.

The Effect of Recombinant Human Bone Morphogenetic Protein-2 in Single-Level Posterior Lumbar Interbody Arthrodesis

Michielsen JJ, Sys JJ, Rigaux AA, et al. — Wed, 15 May 2013 00:00:00 GMT

Background:

In this prospective, randomized controlled trial, our objective was to assess both the clinical and radiographic effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) in patients treated with an instrumented single-level posterior lumbar interbody arthrodesis with polyetheretherketone cages.

Methods:

Forty patients were randomized with a 1:1 ratio. Two patients who had a two-level arthrodesis (L4-L5 and L5-S1) were excluded. Patients completed the Oswestry Disability Index, the Short Form-36, and the visual analog scale preoperatively and postoperatively at three, six, twelve, and twenty-four months. Computed tomography scans with coronal and sagittal reconstructions were made at three, six, and twelve months postoperatively. Interbody arthrodesis was performed using polyetheretherketone cages, which were filled with 8 mg of rhBMP-2 in the study group and 2.5 mL of autologous bone in the control group.

Results:

Baseline demographic data showed no significant difference between groups, except for the body mass index, which was higher in the study group (p = 0.032). There were no significant differences in the clinical results (visual analog scale, Oswestry Disability Index, and Short Form-36) between the groups at each postoperative visit. At three months, end-plate resorption was noted around the cages filled with rhBMP-2 in all patients in the study group. No cage migration or subsidence was observed. Bridging trabecular bone scale scores and bone density measures were significantly lower in the study group. Osteolysis and ectopic bone formation occurred in seven of nineteen patients in the study group and did not occur in the control group. This did not result in radicular symptoms within the time span of this study. At one year, computed tomography scans showed osseous healing in all patients. There were no revision procedures.

Conclusions:

This trial showed no clinical difference when rhBMP-2 was used in posterior lumbar interbody arthrodesis compared with autologous bone. On computed tomography scans, fusion was equally achieved, but trabecular bone formation occurred at a slower rate and interbody bone density was lower within the first year after surgery when rhBMP-2 was used. End-plate resorption, osteolysis, and ectopic bone formation were frequently noted in the rhBMP-2 group.

Level of Evidence:

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Ulnar Collateral Ligament Injuries of the Thumb Phalangeal Translation During Valgus Stress in Human Cadavera

McKeon KE, Gelberman RH, Calfee RP. — Wed, 15 May 2013 00:00:00 GMT

Background:

The clinical diagnosis of thumb ulnar collateral ligament disruption has been based on joint angulation during valgus stress testing. This report describes a definitive method of distinguishing between complete and partial ulnar collateral ligament injuries by quantifying translation of the proximal phalanx on the metacarpal head during valgus stress testing.

Methods:

Sixty-two cadaveric thumbs underwent standardized valgus stress testing under fluoroscopy with the ulnar collateral ligament intact, following an isolated release of the proper ulnar collateral ligament, and following a combined release of both the proper and the accessory ulnar collateral ligament (complete ulnar collateral ligament release). Following complete ulnar collateral ligament release, the final thirty-seven thumbs were also analyzed after the application of a valgus force sufficient to cause 45° of valgus angulation at the metacarpophalangeal joint to model more severe soft-tissue injury. Two independent reviewers measured coronal plane joint angulation (in degrees), ulnar joint line gap formation (in millimeters), and radial translation of the proximal phalanx on the metacarpal head (in millimeters) on digital fluoroscopic images that had been randomized.

Results:

Coronal angulation across the stressed metacarpophalangeal joint progressively increased through the stages of the testing protocol: ulnar collateral ligament intact (average [and standard deviation], 20° ± 8.1°), release of the proper ulnar collateral ligament (average, 23° ± 8.3°), and complete ulnar collateral ligament release (average, 30° ± 8.9°) (p < 0.01 for each comparison). Similarly, gap formation increased from the measurement in the intact state (5.1 ± 1.3 mm), to that following proper ulnar collateral ligament release (5.7 ± 1.5 mm), to that following complete ulnar collateral ligament release (7.2 ± 1.5 mm) (p < 0.01 for each comparison). Radial translation of the proximal phalanx on the metacarpal head did not increase after isolated release of the proper ulnar collateral ligament (1.6 ± 0.8 mm vs. 1.5 ± 0.9 mm in the intact state). There was a significant increase in translation following release of the complete ulnar collateral ligament complex (3.0 ± 0.9 mm; p < 0.01) and an additional increase after forcible angulation of the joint to 45° (4.1 ± 0.9 mm; p < 0.01). Translation 2 mm greater than that in the stressed control was 100% specific for complete disruption of the ulnar collateral ligament complex.

Conclusions:

While transection of the proper ulnar collateral ligament leads to an increase in metacarpophalangeal joint angulation and gapping on stress fluoroscopic evaluation, only release of both the accessory and the proper ulnar collateral ligament significantly increases translation of the proximal phalanx on the metacarpal head.

Clinical Relevance:

A finding of phalangeal translation on a stress fluoroscopic image distinguishes partial from complete tears of the thumb ulnar collateral ligament.

Hemiarthroplasty Did Not Confer Any Benefit in Older Patients with Four-Part Humeral Fractures

Kuhn JE. — Wed, 15 May 2013 00:00:00 GMT

Intra-Articular Infusion with Bupivacaine Decreased Pain and Opioid Consumption After Total Knee Arthroplasty

Pagnano MW. — Wed, 15 May 2013 00:00:00 GMT

Platelet-Rich Plasma Added to the Patellar Tendon Harvest Site During Anterior Cruciate Ligament Reconstruction Enhanced Healing

Nakamura N. — Wed, 15 May 2013 00:00:00 GMT

Patient Satisfaction: Implications and Predictors of Success

Shirley ED, Sanders JO. — Wed, 15 May 2013 00:00:00 GMT

Abstract:

Patient satisfaction is an individual’s cognitive evaluation of, and emotional reaction to, his or her health-care experience. This concept is increasing in importance as survey data are being used by health-care facilities for self-assessment, accreditation requirements, and compensation formulas. High patient satisfaction is associated with increased market share, financial gains, decreased malpractice claims, and improved reimbursement rates. Modifiable factors that contribute to satisfaction include physician-patient communication, the setting of appropriate expectations, minimization of waiting times, and provision of continuity of care. There are also factors that are less amenable to change, including chronic illness, opioid dependence, and sociodemographic status. Satisfaction with a surgical outcome differs from satisfaction with an office visit. Accurate expectations and patient-reported outcome measures are important determinants of satisfaction after a surgical procedure. Physicians can improve patient satisfaction in their practice by understanding the implications of satisfaction and the predictors of success.

High-Fidelity Simulations for Orthopaedic Residents Medical Complications and Systems Challenges

Lee White M, Gilbert SR, Youngblood AQ, et al. — Wed, 15 May 2013 00:00:00 GMT

Surgical training requires acquisition of procedural skills as well as competency in medical management. Changes in training and practice patterns have decreased the operative and nonoperative experiences of trainees. With the introduction of new technologies, more complex procedures, and a host of external constraints, the doctrine of learning primarily through supervised patient-care experiences has been superseded by efforts to teach in nonclinical environments¹. Increasingly, simulation is being used to help learners develop essential operative technical skills to compensate for the loss of experience that historically has been obtained through exposure to cases. Hip fixation, osteotomy and fusion, and arthroscopy are some of the orthopaedic procedures that are taught through simulation^2-4. Despite the attempts to compensate for decreased opportunities for procedural competency training, to our knowledge no one has developed an alternate method to teach clinical skills needed by orthopaedic residents to manage patients in the postoperative period. Residents develop the ability to manage emergency medical situations through exposure to patient problems, just as motor memory is developed through repetitive performance of a procedure. Feedback from more experienced physicians is another important component of learning proper medical management of patients. Whereas operative skill is supervised, thereby providing opportunities for immediate feedback and improvement, postoperative care receives less scrutiny. The simulated setting is an ideal place to practice handling medical emergencies in a standardized manner. Simulation-based medical education is recognized as a method of boosting medical professional performance while enhancing patient safety⁵. It is being used at a rapidly expanding rate for training of health-care providers, including pediatrics, internal medicine, and anesthesia residents, and for medical students, but we believe that this is the first description of a simulation-based medical education course focusing on postoperative care by orthopaedic residents. Our hypothesis was that simulation-based medical education would be well received by orthopaedic residents and that they would feel better able to respond to pediatric orthopaedic postoperative complications, including accessing support systems.

What's New in Foot and Ankle Surgery

Marx RC, Mizel MS. — Wed, 15 May 2013 00:00:00 GMT

New and Improved Medical Test Costs Just One Cent Commentary on an article by Kathleen E. McKeon, MD, et al.: “Ulnar Collateral Ligament Injuries of the Thumb. Phalangeal Translation During Valgus Stress in Human Cadavera”

Benson LS. — Wed, 15 May 2013 00:00:00 GMT

Recombinant Human Bone Morphogenetic Protein-2: What’s a Spine Surgeon to Do? Commentary on an article by J. Michielsen, MD, et al.: “The Effect of Recombinant Human Bone Morphogenetic Protein-2 in Single-Level Posterior Lumbar Interbody Arthrodesis”

Bolesta MJ. — Wed, 15 May 2013 00:00:00 GMT

That’s Why We Call It BIO mechanics! Commentary on an article by H. John Cooper, MD, et al.: “Adverse Local Tissue Reaction Arising from Corrosion at the Femoral Neck-Body Junction in a Dual-Taper Stem with a Cobalt-Chromium Modular Neck”

Padgett DE, Wright TM. — Wed, 15 May 2013 00:00:00 GMT