Introduction

Advances in hip arthroscopy have increased the understanding of both intra-articular and extra-articular hip pathology. The anatomic and surgical techniques involved in hip arthroscopy have been described. Increasing enthusiasm for hip arthroscopy and minimally invasive surgery in addition to advances in magnetic resonance imaging of the hip have broadened arthroscopic application. Intra-articular pathologies—including loose bodies, labral tears, ligamentum teres tears, chondral lesions, synovial chondromatosis and femoroacetabular impingement—have now been arthroscopically treated.

Hip arthroscopy has recently been expanded to allow for the visualization and treatment of extra-articular pathology, specifically in the peritrochanteric compartment. Disorders in this compartment include external coxa saltans or snapping hip, trochanteric bursitis, and gluteus medius and gluteus minimus tears (Tables 17-1, 17-2, and 17-3). These pathologies, which were underappreciated before hip arthroscopy, have now been identified as significant causes of lateral hip pain. The previous treatment of these disorders with conservative modalities or open surgery has had varied efficacy, and it has been associated with significant postoperative morbidity. Conservative treatment is often the preferred treatment modality and includes corticosteroid and anesthetic injections in combination with a structured physical therapy regimen. Patients for whom conservative treatment is ineffective have previously required open surgery.

Table 17–1 External Coxa Saltans

Table 17–2 Trochanteric Bursitis

Table 17–3 Gluteus Medius and Minimus Tears

Indications

• External coxa saltans

Generally asymptomatic or can be treated conservatively with rest, activity modification, stretching, corticosteroid injections, and physical therapy

Recalcitrant cases as defined by unabated symptoms may be addressed with either open or arthroscopic treatment

• Trochanteric bursitis

Conservative treatment with local corticosteroid and anesthetic preparation injections in combination with physical therapy as the mainstay of diagnosis and treatment

Refractory cases treated with open and arthroscopic trochanteric bursectomy

• Gluteus medius and minimus tears

Present as refractory trochanteric bursitis or iliotibial band syndrome with lateral hip pain and an ambulatory limp likely related to hip abductor weakness

Treatment described in an open and arthroscopic fashion when conservative treatment has failed

Brief history and physical examination

An in-depth patient history is one of the most effective tools for evaluating a complaint of hip pain. A historic description of hip pain can differentiate intra-articular versus extra-articular pathology. Extra-articular complaints can then be localized to lateral hip pain in the peritrochanteric compartment. When a description of extra-articular lateral hip pain is achieved, the diagnostic differential can be narrowed with descriptive characteristics specific to each peritrochanteric space disorder. External coxa saltans, or “snapping hip,” is characterized by a palpable or audible snapping as the hip moves from flexion to extension; this is often seen during athletic activity. Trochanteric bursitis and greater trochanteric pain syndrome are characterized by chronic intermittent aching pain over the lateral aspect of the hip; these conditions are prevalent among older females. Gluteus medius and gluteus minimus tears often produce symptoms that are similar to those of trochanteric bursitis but on a shorter time line.

Lateral hip pain can arise from direct pain from the peritrochanteric space or from referred pain from intra-articular pathology. Palpation of the lateral hip aids in the differential diagnosis, because referred pain may be reproduced with passive and active joint motion but should not produce tenderness with direct palpation. In this vein, palpation should begin with the origin of the gluteus maximus at the inferoposterior aspect of the ileum and sacrum. The insertion can then be examined in two locations: the lateral base of the linea aspera on the proximal femur and the tensor fascia latae. Next, the gluteus medius should be palpated from its origin on the anterior and middle aspect of the ileum to its two insertions on the middle and superoposterior facets of the greater trochanter. The gluteus minimus can be examined from its origin deep to the gluteus medius to its insertion at the greater trochanter anterior facet. The greater trochanteric bursa should also be appreciated overlying the greater trochanter at the mid-posterior proximal aspect of the femur. The physical examination of muscle strength can be used to evaluate abductor strength in the presence or absence of pain. This examination should be conducted with the hip in flexion to assess the tensor fascia latae, in neutral to evaluate the gluteus medius, and in extension for the gluteus maximus. This examination should be performed with the knee both flexed and extended to allow for the tension and relaxation of the iliotibial band, respectively. External coxa saltans can be replicated with audible or palpable snapping during physical examination. Gluteus medius and gluteus minimus tears often present with pain along the lateral aspect of the greater trochanter and may mimic trochanteric bursitis.

Imaging and diagnostic studies

All patients who present with hip pain are evaluated with an anteroposterior radiograph of the pelvis as well as a Dunn lateral radiograph (90 degrees of hip flexion, 20 degrees of abduction, and the beam centered on and perpendicular to the hip) to assess for avulsions of the greater trochanter, cam and pincer lesions, loss of joint space, crossover sign, acetabular dysplasia, and sacroiliac joint pathology. Magnetic resonance imaging provides the most information about the soft tissues that surround the hip (Figure 17-1). Every magnetic resonance imaging study of the hip should include a screening examination of the whole pelvis that is acquired with use of coronal inversion recovery and axial proton-density sequences. Detailed hip imaging is obtained with use of a surface coil over the hip joint, with high-resolution, cartilage-sensitive images acquired in three planes (sagittal, coronal, and oblique axial) with use of a fast-spin-echo pulse sequence and an intermediate echo time. Other alternatives include the use of magnetic resonance arthrography of the hip for the evaluation of hip pathology. Ultrasound is used most commonly to confirm the placement of injections into the trochanteric space for diagnostic and therapeutic purposes. Dynamic ultrasound has also been described to evaluate external coxa saltans; it provides real-time images of the sudden abnormal displacement of the iliotibial band or the gluteus maximus muscle overlying the greater trochanter as a painful snap during hip motion. In addition, sonography can identify gluteus medius and gluteus minimus tendinopathy and provide information about the severity of the disease.

Figure 17–1 Magnetic resonance image of the left hip that reveals increased signal at the greater trochanter; this is consistent with a tear of the gluteus medius tendon.

Surgical technique

The importance of proper portal placement is critical during hip arthroscopy. For arthroscopy of the peritrochanteric space, a technique has been described that involves the use of both traditional and unique portals (Figure 17-2). The technique begins with the accurate identification of the trochanter and the marking of the arthroscopic portals. The procedure begins with routine central compartment hip arthroscopy to rule out associated intra-articular pathologies. Although intra-articular pathologies typically result in primary anterior or groin symptoms, it is also possible for these pathologies to result in primary lateral-sided hip pain. Central compartment arthroscopy is performed in all cases of peritrochanteric space endoscopy to document and treat any associated labral or chondral pathology that may coexist with the lateral-based pathology. The anterolateral portal is first established with the use of the standard Seldinger technique of a cannulated trochar over a guidewire, which is performed with the aid of fluoroscopy. To minimize trauma to the lateral femoral cutaneous nerve, a mid-anterior portal is then established. This portal is made slightly more lateral and distal than the traditional anterior portal. The portal is critical to get into the peritrochanteric space, because it is the initial primary viewing portal. Thus, fluoroscopy is used to assist with the optimal placement of the mid-anterior portal over the lateral prominence of the greater trochanter. Before entry into the peritrochanteric space and after the completion of the central compartment evaluation, the peripheral compartment should be entered if there is any concern about peripheral compartment pathology.

Figure 17–2 Intraoperative photograph of the right hip anterolateral (AL), mid-anterior (MA), distal anterolateral accessory (DALA), posterolateral (PL), and proximal anterolateral accessory (PALA) portals for entry into the peritrochanteric space. The anterosuperior iliac spine is denoted by the arrow.

Diagnostic arthroscopy of the peritrochanteric space begins with a blunt trochar placed in the mid-anterior portal, which is then used to swipe between the iliotibial band and the vastus ridge in a controlled manner that is similar to that performed in the subacromial space in the shoulder. The trochar is aimed directly for the lateral prominence of the greater trochanter; this is the safest starting position for blunt trochar placement. If the trochar is placed too proximally initially, violation of the gluteus medius musculature may occur; if it is placed too distally, the trochar may disrupt the fibers of the vastus lateralis. The use of fluoroscopy helps to precisely identify the starting position to avoid iatrogenic injury to the surrounding soft tissue. Unlike the central compartment, in the peritrochanteric space, traction is not necessary. At times, however, minimal traction is used to maintain tension on the abductors.

After the space has been defined, a 70-degree scope is placed in the mid-anterior portal. The camera is oriented so that both the light source and the camera base are pointed distally. Such an orientation places both the tail of the 70-degree scope and the light source on the proximal portion of the patient, with visualization directed distally.

The first structure to be visualized is the gluteus maximus tendon inserting on the femur just below the vastus lateralis (Figure 17-3). This structure is a reproducible landmark that provides good orientation within the space. It is typically unnecessary to work distal to the gluteus maximus tendon, and one should avoid exploration posterior to the tendon, because the sciatic nerve lies within close proximity (i.e., 2 cm to 4 cm). The camera light source is then directed to the lateral aspect of the femur, where the longitudinal fibers of the vastus lateralis can be visualized and followed proximally to the vastus ridge. The insertion and muscle belly of the gluteus medius are located proximal to this, whereas the gluteus minimus is located more anteriorly and is mostly covered. Finally, the iliotibial band is identified with the camera looking proximally and laterally.

Figure 17–3 Arthroscopic image of the attachment of the gluteus maximus tendon to the linea aspera. This is the starting point to gain orientation in the peritrochanteric space and to begin a systematic evaluation of the compartment.

( From Shindle MK, Voos JE, Heyworth BE, et al. Hip arthroscopy in the athletic patient: current techniques and spectrum of disease. J Bone Joint Surg Am. 2007;89 Suppl 3:29–43.)

Gluteus Medius Repair

If there is evidence of significant gluteus medius pathology, an arthroscopic repair is performed (Figure 17-4). Occasionally, gentle distraction of the hip is needed to place the gluteus medius muscle fibers on tension to more clearly delineate proximal bursal tissue from gluteus medius muscle fibers. The 70-degree arthroscope is then placed in the proximal anterolateral accessory portal to get a more global view of the abductors, whereas the working instruments can be placed in the mid-anterior and distal anterolateral accessory portals.

Figure 17–4 Arthroscopic image that reveals a full-thickness tear of the gluteus medius tendon.

Most commonly, the medius is degenerated and torn off of its distal insertion onto the lateral facet of the trochanter with proximal extension. Often the tear is predominantly an undersurface tear that is analogous to an articular-sided rotator cuff tear, which then extends posteriorly to become a full-thickness tear. Close scrutiny of the magnetic resonance images is critical to correlate intraoperative findings with the preoperative imaging. Sometimes the initial intraoperative finding is the significant thinning of the tendon insertion, which requires the completion of the tear with facet bone preparation and subsequent reattachment.

The technique for fixing these tears is quite similar to that of repairing rotator cuff tears. First, a probe or grasper is used to manually reduce the tear to its anatomic position in the footprint. With a burr, the lateral facet is burred to a bleeding edge of bone in a similar fashion as is done to the greater tuberosity during a rotator cuff repair. A spinal needle is placed to find the proper angle for anchor placement, and then two metallic anchors are usually placed as a result of the hard nature of the bone in the trochanter. These anchors can be placed percutaneously to achieve the optimal angle into the bone. Fluoroscopy is again useful at this stage of the procedure to confirm the proper positioning of the anchors. A suture-passing device is then used to pass the suture through the tendon from posterior to anterior in a sequential fashion (Figure 17-5). Proper suture management is critical. Extra-long cannulas are used to help manage the suture and to tie arthroscopic knots. Finally, after all of sutures are passed, arthroscopic sliding, locking knots are created, with a knot pusher securing the medius back to its native footprint on the trochanter (Figure 17-6)

Figure 17–5 Arthroscopic image of the hip after suture anchors have been placed in the greater trochanter. The sutures are passed through the tendon in preparation for repair.

Figure 17–6 Arthroscopic image of the hip after the final repair of the gluteus medius tendon edge to its footprint on the greater trochanter. The knots were secured with the use of arthroscopic knot-tying techniques.

Technical Pearls

• The placement of the initial mid-anterior portal should be performed under fluoroscopic guidance to confirm placement over the lateral prominence of the greater trochanter to avoid entry into the vastus lateralis distally and the gluteus medius muscle proximally.

• The initial view in the space should be directed toward identifying the gluteus maximus tendon insertion into the linea aspera. This allows the surgeon to gain proper orientation in the space, and it provides a boundary to protect the sciatic nerve, which is 4 cm posterior to the insertion point.

• A complete bursectomy should be performed before tendon evaluation.

• Slight axial traction on the limb will help to tension the gluteus medius fibers to allow for easy distinction between the inflamed bursa and the normal gluteus medius muscle tissue.

• Place anchors perpendicular to the trochanter with fluoroscopic assistance.

• A small stab incision at level of the posterolateral peritrochanteric portal is an ideal location for anchor placement.

• Extra-long plastic threaded cannulas should be used during suture passage to provide for optimal suture management.

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Postoperative rehabilitation

Rehabilitation for patients after bursectomy or iliotibial band release limits weight bearing to 20 lb with the foot flat as tolerated with crutches for the first 2 weeks postoperatively. Full weight bearing is advanced without crutches as the patient’s pain tolerates. Range of motion and hip strengthening without restrictions begin as soon as the patient’s pain allows. It is important to avoid aggravating the lateral hip with therapy that is too aggressive immediately after surgery.

For patients undergoing the repair of gluteus medius and gluteus minimus tears, physical therapy consists of 6 weeks of 20-lb flat-foot weight bearing with crutches. The patient is fitted with a hip abduction brace that blocks active abduction, and no limitation of hip flexion or extension is required. Isometric strengthening of the hip abductors should begin at 6 weeks. At 12 weeks, more aggressive strengthening and activity are introduced. Running is not allowed until the patient displays equal abductor strength bilaterally to support the pelvis.

Results and outcomes

In most cases, external coxa saltans is asymptomatic, or it can be treated conservatively with rest, activity modification, stretching, corticosteroid injections, and physical therapy (Table 17-4). Zoltan and colleagues described an open surgical technique for the treatment of recalcitrant external coxa saltans that involved the excision of an ellipsoid-shaped portion of the iliotibial band overlying the greater trochanter and the removal of the trochanteric bursa. Postoperative follow up demonstrated that 80% of patients (4 out of 5) had significant improvement or relief of their symptoms, whereas 20% (1 out of 5) had no improvement. A minimally invasive technique that makes use of transverse step cuts into the fascia along a longitudinal facial incision has also been described. Fourteen of 16 hips remained asymptomatic postoperatively. The treatment of external coxa saltans with endoscopic iliotibial band release has been described by multiple authors with promising results. At an average follow up of 2 years, Ilizaliturri and colleagues reported 10 of 11 patients as having the complete resolution of pain and symptomatic snapping.

Conservative treatment in the form of one or two local corticosteroid and local anesthetic preparation injections in combination with physical therapy is the mainstay of diagnosis and treatment. This therapeutic regimen has resulted in excellent responses in 66% of cases and improvement in the remaining 33%. However, conservative therapy is not without its drawbacks. Multiple or inappropriately placed corticosteroid injections have been associated with gluteus medius injury, and open trochanteric bursectomy has been described for these refractory cases (Table 17-5). Trends toward arthroscopic treatment have also produced descriptions of endoscopic bursectomy. Baker and colleagues recently published a prospective follow up report of 25 patients treated with endoscopic bursectomy at a mean of 26.1 months postoperatively. Significant improvement was found in visual analog scale results, Harris Hip Scores, and Short Form 36 (SF-36) results. One postoperative complication occurred: a seroma that required repeat surgery. One patient had a failed arthroscopic bursectomy and subsequently underwent open bursectomy that resulted in the resolution of symptoms. Improvements in a patient’s status that are likely to be lasting are usually evident by 1 to 3 months after surgery.

The insertions of the gluteus medius and the gluteus minimus at the greater trochanter and tears at this insertion have been described synonymously with tears of the rotator cuff tendons (Table 17-6). As a result of the similarities, injuries to the abductor tendons have been called rotator cuff tears of the hip. Tears were initially identified in the setting of open debridement for recalcitrant trochanteric bursitis, total hip arthroplasty, and the treatment of femoral neck fractures. Descriptions of calcific tendonitis of the hip have also included relationships with gluteus medius and gluteus minimus tears, thus further substantiating the rotator cuff similarity. Conservative treatment has included physical therapy and corticosteroid injection. Treatment has been described in an open fashion when encountered in the setting of refractory iliotibial band syndrome and total hip arthroplasty. The true incidence of gluteus medius and gluteus minimus tears is not known. A prospective study by Bunker and colleagues of 50 patients with fractures of the femoral neck revealed a 22% incidence of tears of the gluteus medius and the gluteus minimus. In addition, Howell and colleagues conducted another prospective study of 176 consecutive patients who underwent total hip arthroplasty for osteoarthritis, and they identified 20% of these patients as having degenerative pathology. Recently, the arthroscopic treatment of trochanteric bursitis and calcific tendonitis of the gluteus medius and the gluteus minimus has been reported by Kandemir and colleagues. Voos and colleagues reported about an arthroscopic approach that provides access for the repair of gluteus medius and gluteus minimus tendon tears. Results of this technique for 10 patients with 12 to 31 months of follow up demonstrated the full resolution of pain in 100% of patients, with 9 out of 10 patients recovering their full former strength. Moreover, an increasing understanding of the gluteus medius tendon attachment morphology may help in the development of future reparative techniques.

Complications

There are few complications inherent to surgical procedures in the peritrochanteric space. The main complications include fluid extravasations into the soft tissues and hematomas. There have been no formal reports in the literature regarding the incidence of these complications.

The recurrence of trochanteric bursitis, painful external coxa saltans, and the retearing of gluteus medius tendon repairs can all occur, although the incidences of these complications have not been reported. The senior author had one deep venous thrombosis occur postoperatively after addressing peritrochanteric space pathology.