A prospectively designed, computerized database of patients undergoing total hip arthroplasty by a single surgeon was examined. From this database, all revision arthroplasty cases were reviewed. A consecutive series of fifty-one patients who underwent revision total hip arthroplasty through the direct anterior approach was reviewed. Data reviewed included demographic information, surgical indications, intraoperative technique, and complications, as well as preoperative and postoperative outcome measures.
Surgical Technique
At the recent turn of the century, few surgeons in North America or Europe were routinely performing the single-incision anterior approach for total hip arthroplasty. Many of those surgeons had been exposed to the work of Judet or Letournel in Paris, who had been performing the surgical approach routinely as early as 194721. The procedure has persisted, with a few minor alterations, in the hands of the senior author (F.L.). The technique for primary anterior-supine total hip arthroplasty is now well described22. This technique is briefly reviewed, with emphasis on the differences employed in revision circumstances. Extensions of the basic technique are described in subheadings.
Standard Approach
For all arthroplasty procedures in which an anterior approach will be used, the authors are proponents of a special operating table that provides operative assistance by facilitating the exposure of the acetabulum and the use of intraoperative fluoroscopy. Furthermore, use of this operating table has allowed the senior surgeon to perform the procedures with no more than a single scrubbed assistant. Either the traditional Judet-type table (Tasserit, Nevers, France) or the Medacta extension to the standard orthopaedic table (Medacta, Lugano, Switzerland) were used in this series.
The patient is positioned supine and secured to the table. A well-padded perineal support is routinely used. The foot on the involved extremity is secured in the traction boot and affixed to the movable spar. The pelvis is leveled and previous incisions are marked with indelible ink prior to the surgical preparation. The patient is widely prepared from the inferior costal margin to the level of the ipsilateral knee. This allows for surgical extension as necessary in both the proximal and distal directions. The field is draped in the usual fashion. The standard 8 to 10-cm oblique surgical incision is used for most patients. The incision is positioned over the belly of the tensor fasciae latae muscle.
Skin and subcutaneous tissues are incised, and hemostasis is obtained. The fascia of the tensor fasciae latae is split and the tensor fasciae latae muscle is mobilized from the sheath. In revision cases in which a previous anterior approach will be used, this fascial layer is a good landmark to follow around the muscle belly of the tensor fasciae latae. Once the tensor fasciae latae muscle is mobilized, continuing through the floor of the tensor sheath and exposing the hip capsule allows the surgeon to proceed as with the standard anterior approach. The lateral femoral circumflex vessels are ligated in the distal portion of the incision.
In all revision or complex cases, in contrast to what is done in a primary total hip arthroplasty, routine sectioning of the tendinous indirect head of the rectus femoris muscle is performed. This aids in the exposure of the superior lateral surface of the ilium and anterior aspect of the acetabular rim for osseous reference.
Often a more complete capsulectomy is required during revision surgery, especially if additional mobilization of the femur is required to access the acetabulum. As in a primary arthroplasty, capsular release is usually required at the posteromedial aspect of the femoral neck, immediately adjacent to the lesser trochanter. Additional bands of hip capsule, usually between the posterior portion of the acetabulum and the posterolateral aspect of the femoral neck, are commonly released close to the femur to minimize the risk of iatrogenic nerve injury. Inadequate capsular release is the most common reason for poor visualization of the femur.
If isolated acetabular revision is performed with retention of the femoral stem, the femoral head is usually removed with care to avoid damage to the femoral component. A pocket is made by incising or excising the superolateral capsule. By flexing the hip to approximately 30° and externally rotating the femur approximately 45°, the femur can be subluxated into this pocket with slight pressure applied to the plantar surface of the foot. The acetabulum is then accessed by working over the medial aspect of the femoral neck (Fig. 1).
Access to the acetabulum during revision anterior-approach total hip arthroplasty is accomplished over the medial aspect of the femoral neck. Externally rotating the femur to 45°, flexing the hip to approximately 30°, and subluxating the femur proximally positions the femoral neck out of the way so that the acetabulum can be prepared.
After removal of the acetabular cup with use of curved chisels or a specially modified explantation device (Explant; Zimmer, Warsaw, Indiana) (Fig. 2), the remaining bone is prepared with use of standard revision arthroplasty techniques. A variety of revision acetabular implants can be used. Particularly effective in cases of inadequate bone stock are reconstruction cages or cups with a hook and flange, as access to the region required for fixation of the cup requires little, if any, additional exposure.
Examples of the Explant acetabular-cup removal system (Zimmer), modified for use in the Hueter-interval surgical approach.
Proximal Extension
The Levine modification of the Smith-Peterson surgical approach was originally used for surgical treatment of acetabular fractures. The Levine approach is still commonly employed as the preferred surgical approach for periacetabular osteotomy14,15 and for anterior arthrodesis of the hip13. The approach can allow acute treatment of acetabular fractures by total hip arthroplasty12. This approach improves on the standard exposure by providing excellent visualization of the anterior column and limited (usually palpable) visualization of the quadrilateral surface of the pelvis.
The fascia of the tensor fasciae latae is divided at the proximal extent of the incision, to the anterior superior iliac spine. Care is taken at the anterior superior iliac spine to protect the lateral femoral cutaneous nerve. The external oblique aponeurosis is identified as it inserts on the iliac crest and is exposed to the gluteus medius pillar of the acetabulum. Sharp dissection or electrocautery is used to elevate the abdominal muscles off the iliac crest, and the iliacus muscle is elevated in a subperiosteal manner off the inner table of the iliac wing. A laparotomy sponge is placed on the inner table of the pelvis. Finally, the inguinal ligament with the attachments of the sartorius and direct head of the rectus femoris muscle is released to connect the two exposures. Care is taken to stay within the tensor fasciae latae sheath distally to maintain this structure so as to protect the lateral femoral cutaneous nerve. The exposure is then extended medially, following the inner surface of the anterior column, as the psoas muscle is elevated in a subperiosteal manner. At this point, the entirety of the inner table of the pelvis and much of the anterior column are visible (Figs. 3-A, 3-B, and 3-C). With flexion of the hip, the quadrilateral surface can be palpated.
Figs. 3-A and 3-B Intraoperative photographs made of the hip before (Fig. 3-A) and after (Fig. 3-B) acetabular revision, demonstrating proximal intrapelvic extension of the Hueter approach to allow visualization of the anterior column and iliac crest to the level of the pubic eminence. In the case of this hip, a defect of the anterior column was grafted and the acetabular shell was revised. Fig. 3-C A schematic of the defect and exposure is demonstrated with regard to the hip shown in Figs. 3-A and 3-B.
Closure of the exposure begins with reapproximation of the rectus femoris tendon to the anterior inferior iliac spine and then reapproximation of the sartorius tendon and inguinal ligament to the anterior superior iliac spine. This usually requires the use of strong, nonabsorbable suture passed through drill holes in the bone. The aponeurosis of the external oblique is reapproximated to the ilium, and the fascia of the tensor fasciae latae is closed with absorbable suture. Drains are left deep in the pelvis and around the hip.
Proximal extension can also proceed in an extrapelvic fashion. The Hueter interval as a portion of the Smith-Peterson approach to the hip is a truly extensile approach that can be extended to access the entire outer table of the ilium and the anterior and posterior columns. This extension of the Hueter interval approach becomes a portion of the extended iliofemoral approach. While the extended iliofemoral approach has been described and utilized in the context of total hip arthroplasty23, only 1 to 2 cm of additional proximal extension has been required in our presented series.
The approach is again directed proximally. The skin incision courses proximally and along the iliac crest at the anterior superior iliac spine. The incision of the tensor fasciae latae fascia extends to the anterior superior iliac spine. The tensor fasciae latae muscle is mobilized proximally but not divided from its origin at this point. Frequently the supra-acetabular anastomosis of the superior gluteal artery is encountered at the area of the interspinous crest24; this can become a source of bleeding if not anticipated. Once the tensor fasciae latae is mobilized, the anterior column of the ilium can be palpated. Subperiosteal dissection then proceeds underneath the gluteus minimus muscle and along the outer surface of the ilium from anterior to posterior. This creates a pocket underneath the gluteus minimus and tensor fasciae latae where implants or instruments can be placed. Care should be taken at the proximal aspect of the greater sciatic notch to not injure the neurovascular pedicle to the superior gluteal artery. If bleeding is encountered, packing is recommended, as blind cauterization or clamping may injure the superior gluteal nerve and affect hip abductor muscle function.
If additional exposure is required posteriorly, the tensor fasciae latae must be mobilized from the ilium. To mobilize the tensor fasciae latae from its origin, an osteotomy of the anterior superior iliac spine, including the anterior third of the crest, can be performed. Alternatively, reinforcing the tendinous origin with suture prior to sharply elevating the fibers off the crest can minimize fraying of the tensor and facilitate its closure. This latter technique can be helpful if only a few centimeters of excursion of the tensor fasciae latae is required by the exposure.
Distal Extension
While the acetabular exposure is relatively straightforward, the femoral exposure in revision anterior-approach surgery can be difficult.
The surgical dissection to the femur is dictated largely by the technique required. Small percutaneous incisions or windows can be used and have been successfully employed in a large series of patients16. When the technique to be employed requires a more extensive exposure, as in the performance of cerclage wiring of the femur or extended osteotomy for extraction of a well-fixed femoral stem, an open technique is preferred.
The anterior approach can be extended distally by extending the skin incision in a posterior direction to the lateral surface midline. It should be possible to palpate the iliotibial band at this point. The fascial incision is carried distally and posteriorly until the fascia lata is encountered. The fascial incision is then directed distally, splitting the anterior third of the fascia lata. The distance of the fascial split is dictated by the amount of femoral exposure that is required. Once the incision is deep to the iliotibial band, the vastus lateralis muscle can be elevated subperiosteally beginning posteriorly or can be split, depending on surgeon preference and the amount of femur requiring exposure.
An alternative and more traditional exposure of the femur can be obtained by making a separate lateral approach along the posterior palpable border of the femur. The authors recommend leaving an adequate skin bridge (5 to 7 cm) between the two incisions. The exposure is carried down to and splits the iliotibial band, allowing for a standard lateral approach to the femur. The proximal aspect of the greater trochanter can be reached in this manner.
The anterior approach for arthroplasty of the hip has a long tradition in some parts of the world. For those who trained under Letournel or the Judets, the approach was considered a "standard" approach to the hip. As minimally invasive techniques for arthroplasty were investigated, this technique was rediscovered. In France, these procedures were performed on the Judet table (Tasserit), which became a model for many of the newer tables used for this technique.
Kennon et al.16 presented a large series of revision arthroplasties performed via the anterior approach, which to our knowledge was the first and, to the time of this writing, only series (in the English-language literature) of revision hip arthroplasty performed through the direct anterior approach. The results presented in our series are comparable with the results of the series by Kennon et al. Furthermore, important distinctions that differentiate our series are the routine use of the orthopaedic table designed for this application and a discussion of the Levine approach to the interior aspects of the pelvis. Our series, while small, demonstrates the versatility of the anterior approach in addressing acetabular problems. More importantly, these cases adequately demonstrate anatomic concerns when choosing the anterior approach for the purposes of complex or revision arthroplasty (Fig. 4).
Postoperative anteroposterior pelvic radiograph demonstrating the Kerboull cage construct that was implanted with use of the Hueter surgical approach.
Concerns that might sway a surgeon away from using the anterior approach in the revision setting include the revision of long, extensively porous-coated femoral stems; the presence of profound proximal bone loss or osteolysis, which increases the risk of trochanteric fracture and nonunion and creates problems with effecting stability of the implant through a limited femoral exposure; and the presence of marked retrotorsion of the femoral stem. In two of the presented cases in which a femoral revision was anticipated because of the presence of marked femoral retrotorsion, the exposure of the femoral component was very difficult because, even with 100° of external rotation of the femur, the neck of the femoral implant remained deep within the acetabulum.
Anterior-approach revision hip arthroplasty does offer some advantages over other techniques. In the case of an isolated acetabular liner exchange, cup revision, or revision of failed resurfacing procedures, the exposure is no different from that used during primary arthroplasty. As such, the recovery and rehabilitation can be similar to those of a patient who has undergone primary anterior-approach arthroplasty. In our series of patients undergoing revision anterior-approach total hip arthroplasty, generally good postoperative function could be obtained (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC] score of 83). Interestingly, in the subset of revision anterior-approach total hip arthroplasty for the diagnosis of failed resurfacing (n = 7), short-term WOMAC scores of >95 were demonstrated for all patients. When revision anterior-approach total hip arthroplasty is performed in the setting of previous posterior or anterolateral approaches, there is usually less scarring to contend with during the approach. Even when revision of a prior arthroplasty through an anterior approach is planned, the anatomy can often be approached in the same fashion as in a primary arthroplasty. There were no postoperative dislocation precautions instituted in our series, and there were no dislocations.
With the growing interest in the Hueter interval as a surgical approach for total hip arthroplasty, there is room for a discussion of the anatomic extension of the approach. The context in which this discussion becomes most important is in the realm of complex or revision arthroplasty. In this context the experienced surgeon must utilize an intimate understanding of applied anatomy to decide on the optimal approach to manage the individual surgical problem. A benefit of this discussion would be to equip surgeons who are relatively new to the technique of primary anterior-approach arthroplasty with tools to allow them to address situations that can occur early in the learning curve.