Arthroscopic Iliopsoas Release and Lengthening

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CHAPTER 18 Arthroscopic Iliopsoas Release and Lengthening

Victor M. Ilizaliturri, Jr.

Introduction

Iliopsoas tendon lengthening has traditionally been a procedure that is performed with an open approach and that is used mainly for the treatment of coxa saltans interna or medial snapping hip syndrome. Other indications include iliopsoas irritation syndrome after hip arthroplasty and spastic hip subluxation. The evolution of surgical techniques and technology for hip arthroscopy has allowed for endoscopic techniques for the release or lengthening of the iliopsoas tendon.

Snapping phenomenon of the iliopsoas tendon

The internal snapping hip syndrome is produced by the iliopsoas tendon passing over the iliopectineal eminence or the femoral head. The iliopsoas tendon is located lateral to the iliopectineal eminence when the hip is in full flexion; with hip extension, the tendon is displaced medially until it is positioned medial to the iliopectineal eminence when the hip is in a neutral position. The snapping phenomenon occurs without pain in up to 10% of the general population and should be considered a normal occurrence.

Iliopsoas impingement can be present in up to 4.3% of patients after total hip replacement. This phenomenon mainly occurs as a result of prominent anterior cup rims of reinforcement rings and extruded cement.

Indications

• Internal snapping hip syndrome or coxa saltans interna

• Iliopsoas impingement after total hip replacement

• The treatment of soft-tissue contractures in spastic patients

History and physical examination

The symptomatic internal snapping hip syndrome always presents with pain in the groin associated with the snapping phenomenon. The snapping phenomenon is reproduced when bringing the hip to extension from a flexed position. Patients with this condition report snapping while climbing stairs or when standing up from sitting in a chair. The snapping phenomenon is always voluntary and reproducible. It commonly affects women, with the typical patient having a history of participating in sports. Ballet dancers have a high incidence of snapping hip syndromes. The snapping phenomenon may occur initially without pain and become painful after a traumatic event or after prolonged participation in sports.

The physical examination of patients with the internal snapping phenomenon is performed with the patient supine; the affected hip is flexed to more than 90 degrees and extended to a neutral position. This may be accentuated with abduction and external rotation in flexion and by adducting and internally rotating the hip while extending it. The snapping phenomenon is not visible at the groin. It may be audible, or it may be palpated by placing the hand over the affected area of the groin. There is always an apprehension response from the patient when the snapping occurs.

Imaging studies

The plain radiographs obtained for these patients are usually normal. In some cases, a femoroacetabular impingement deformity may be seen on a plain x-ray; this deformity may be related to the iliopsoas snapping phenomenon.

Psoas bursography may outline the tendon, and, in combination with fluoroscopy, it may document the snapping phenomenon dynamically. The main problem is that this type of imaging depends on the ability of the technician to reproduce the snapping while examining hip motion within the range of view of the C-arm, and it is an invasive study. Ultrasonography of the iliopsoas tendon is a dynamic, noninvasive study that may document both the snapping phenomenon and the pathologic changes of the iliopsoas tendon and its bursa. Psoas ultrasonography also depends on the ability and experience of the examiner. Because almost half of patients with internal snapping hip syndrome have associated intra-articular hip pathology, magnetic resonance arthrography is the diagnostic study that our practice prefers. It may demonstrate intra-articular pathology as well as changes related to the iliopsoas tendon and the bursa. The snapping phenomenon cannot be documented with the use of magnetic resonance arthrography.

Treatment is initially conservative with physical therapy, nonsteroidal anti-inflammatory drug therapy, and corticosteroid injections. If there is no positive response to conservative treatment, then surgical treatment is indicated.

Surgical technique

The endoscopic release of the iliopsoas tendon can be performed with the use of one of two different techniques: release at the level of the insertion of the tendon on the lesser trochanter or release at the level of the hip joint by accessing the bursa through an anterior hip capsulectomy. With both techniques, hip arthroscopy is performed first. Intra-articular lesions are identified and treated before the hip periphery and the psoas bursa are accessed.

Patient Positioning

The supine position and the lateral decubitus position have both been described for hip arthroscopy, and iliopsoas tendon release can be performed with the patient in either one.

We prefer to use the lateral decubitus technique. We position the patient lateral and resting on the nonoperative side on a fracture table with special accessories (Maquet, Rastatt, Germany). A horizontal perineal post with a diameter of 10 cm is positioned horizontally on the operating table; it is then positioned laterally on the patient’s medial thigh and elevated to provide a lateralization vector to the traction force. The lateralization also distances the post from the pudendal nerve. The foot on the surgical side is fixed to the traction device of the fracture table, and the nonoperative side rests free on the table. Before traction is applied, the patient’s genitalia should be inspected to verify that they are free from compression.

The hip is positioned in 20 degrees of flexion to relax the anterior hip capsule. Flexion of more than 20 degrees does not improve the distraction of the hip joint, and it in fact increases the possibility of injury to the sciatic nerve. Abduction is kept neutral to maximize the separation of the iliofemoral joint. Neutral rotation is preferred while establishing arthroscopic portals to maximize the distance between the posterior edge of the greater trochanter and the sciatic nerve.

The C-arm is positioned horizontally under the table to provide an anteroposterior view of the hip. A traction test is performed to confirm effective separation of a minimum of 10 mm between the femoral head and the acetabulum at the image intensifier. After a successful traction test is performed, the hip is flexed 35 degrees, abducted, and externally rotated to confirm the mobility of the setup; this mobility will provide adequate access to the hip periphery. The hip is brought back to a neutral position, and the surgical area is prepared for surgery in the standard fashion.

Iliopsoas Release at the Lesser Trochanter

Arthroscopy of the central compartment is performed first with the use of traction. Three portals are usually established for arthroscopy of the central compartment: an anterolateral portal, a posterolateral portal, and a direct anterior portal. Traction is released to access the peripheral compartment, and accessory portals are usually required to access the hip periphery.

After hip arthroscopy of the central and peripheral compartments is complete, the instruments are taken out of the joint. The hip is positioned in 20 degrees of flexion and external rotation to expose the lesser trochanter at the image intensifier (Figure 18-1). A spinal needle is introduced through an accessory portal (i.e., the superior accessory portal) that is established about 2 cm distal to a horizontal line directed anteriorly from the tip of the greater trochanter and 2 cm anterior to the anterior femur (Figure 18-2). The needle is directed toward the lesser trochanter and navigated by the image intensifier (Figure 18-3). Orientation in the coronal plane is provided by the image intensifier. Orientation in the sagittal plane is provided by palpating the anterior aspect of the femur until the needle is positioned on the lesser trochanter; this will position the needle inside of the iliopsoas bursa. After the spinal needle has been successfully positioned in the iliopsoas bursa, the stylus is removed, and a flexible guidewire (Nitinol) is introduced. The needle is removed, and a cannulated switching stick is passed into the iliopsoas bursa over the flexible guidewire. A 4.5-mm, double-valve, rotatable arthroscopic cannula is passed over the switching stick, which is then removed, and then a 4-mm, 30-degree arthroscope is introduced. The fluid pump is started, and the iliopsoas tendon is identified. A second accessory portal 3 cm to 4 cm distal to the first one is established (i.e., the inferior accessory portal). A spinal needle is triangulated toward the tip of the arthroscope inside of the iliopsoas bursa. The image intensifier can be used to assist with the navigation of the needle. The tip of the needle is identified endoscopically inside of the iliopsoas bursa, and a working portal is established with the use of a flexible guidewire, a cannulated switching stick with a dilator, and a slotted cannula (Hip Access System, Smith and Nephew, Andover, MA). A shaver is introduced through the slotted cannula, which is then removed. The shaver is used to resect synovial tissue from the iliopsoas bursa and to dissect the iliopsoas tendon. The slotted cannula is reinserted with the use of the shaver as a guide. The shaver is removed, and a radiofrequency hook probe is inserted; the slotted cannula is removed, and the radiofrequency probe is used to release the iliopsoas tendon close to its insertion on the lesser trochanter (Figures 18-4 and 18-5). The image intensifier can be used to verify the position of the radiofrequency hook probe before the release of the iliopsoas tendon.

Figure 18–1 This photograph demonstrates a patient positioned for hip arthroscopy on the left side. Only the left foot is fixed to the traction device. Note the extra-padded perineal post in a horizontal position and the image intensifier placed horizontally under the table. The hip is without traction and externally rotated to expose the lesser trochanter at the image intensifier. To the left, a photograph from the image intensifier demonstrates the exposure of the lesser trochanter with external rotation (arrow). Note that the hip is without traction.

Figure 18–2 This photograph demonstrates portal sites. The greater trochanter (GT) and the anterosuperior iliac spine (ASIS) have been outlined. The anterolateral portal and posterolateral portal are at the anterosuperior and posterosuperior corners of the greater trochanter. The direct anterior portal is 1 cm medial to the crossing of a horizontal line from the tip of the greater trochanter and a vertical line from the anterosuperior iliac spine. An anteroinferior accessory portal is located distal to the central compartment portals (i.e., the anterolateral, posterolateral, and direct anterior portals) 1 cm to 2 cm anterior of the anterior aspect of the proximal femur. The black circle indicates our preferred site for the working portal in the case of an iliopsoas tendon release at the lesser trochanter. The white circle indicates our preferred site for the working portal in the case of a transcapsular iliopsoas tendon release.

Figure 18–3 Fluoroscopy photograph of a right hip. Note the lesser trochanter exposed by external rotation. A spinal needle has been introduced through an accessory portal into the iliopsoas bursa and on to the lesser trochanter. Note that the hip is without traction.

Figure 18–4 This photograph demonstrates the arthroscope in position at an accessory portal. A slotted cannula is in position at the distal accessory portal, and a radiofrequency instrument is being introduced through the slotted cannula. The fluoroscopy image demonstrates the position of instruments above the lesser trochanter.

Figure 18–5 Bursoscopic sequence of photographs of an iliopsoas tendon release at the lesser trochanter of the right hip. A, A slotted cannula (SC) is in position in the iliopsoas bursa. The iliopsoas tendon (IPT) is at the bottom of the photograph and surrounded by synovial tissue. B, The synovial tissue around the iliopsoas tendon (IPT) has been resected with a shaver. A radiofrequency hook probe is being introduced for the retrograde release of the iliopsoas tendon. C, The iliopsoas tendon has been released. The lesser trochanter (LT) is at the bottom of the photograph. A radiofrequency hook probe is being removed from the bursa through a slotted cannula (SC).The muscle fibers of the iliacus are behind the hook probe.

Transcapsular Iliopsoas Tendon Release

The iliopsoas tendon also can be released endoscopically at the level of the hip joint through an anterior hip capsulectomy. We perform this procedure with the patient in the lateral decubitus position, but it can also be performed with the patient in the supine position. After arthroscopy of the central compartment is complete, the instruments are taken out of the joint, and the traction is released. The hip is flexed 30 degrees and externally rotated, and the hip periphery is accessed through an accessory portal as described for the iliopsoas tendon release at the lesser trochanter. The spinal needle is directed to the hip capsule at the level of the anterior femoral neck in an angle that is almost perpendicular to the femoral neck, and cannulated instruments are used to establish a viewing portal. A second accessory portal (i.e., the working portal) is established with the use of a spinal-needle–guidewire technique and cannulated instruments by triangulating toward the tip of the arthroscope inside of the hip periphery. The working portal is usually distal to the central compartment portals (i.e., the anterolateral, posterolateral, and direct anterior portals) and between the first accessory portal and a vertical line that descends from the anterosuperior iliac spine (Figure 18-6; see also Figure 18-2). The iliopsoas tendon is located immediately anterior to the hip capsule; it is always found in the space between the anterior zona orbicularis and the anterior labrum proximal and anterior to the medial synovial fold. A communication may exist at this level between the hip capsule and the iliopsoas bursa. In most cases, the hip capsule is thinner at this region, and the iliopsoas tendon can be visualized through the thin portion of the hip capsule. A capsulectomy is performed at this level to gain access to the iliopsoas bursa and the tendon; we use a radiofrequency hook probe passed through a slotted cannula. After the capsulectomy is performed, synovial tissue from around the tendon is resected with the use of a shaver. The tendon is released with a radiofrequency hook probe (Figure 18-7). A slotted cannula is also used to introduce and interchange instruments in the iliopsoas bursa through the defect on the anterior hip capsule.

Figure 18–6 Fluoroscopy photograph that demonstrates the position of instruments introduced to the iliopsoas bursa through an anterior hip capsule window.

Figure 18–7 Arthroscopic sequence that demonstrates the transcapsular release of the iliopsoas tendon in a right hip. A, Arthroscopy of the hip periphery. The inferior femoral neck (FN) is at the top of the photograph, with the medial synovial fold (MSF) below it. The anteroinferior labrum (L) is to the right of the photograph. The zona orbicularis (ZO) is at the bottom. B, The medial synovial fold (MSF) is at the top of the photograph, with the anterolateral labrum (L) to the left. A radiofrequency hook probe is being used to create a window at the anterior hip capsule between the labrum and the zona orbicularis (ZO). The red line indicates the direction of the cut. C, The window on the anterior hip capsule (HC) has been completed. A shaver is being used to resect the synovial tissue around the iliopsoas tendon (IPT). The labrum (L) is to the right of the photograph. D, The iliopsoas tendon (IPT) had been completely exposed. The inferior limit of the hip capsule (HC) window is at the top of the photograph.

After the tendinous portion of the iliopsoas has been released, the iliacus muscle is visible behind the retracted tendon stumps. In our practice, we do not release the iliacus muscle (Figure 18-8). Partial release with both techniques is achieved by not releasing the fibers from the iliacus muscle.

Figure 18–8 Arthroscopic photograph after the release of the iliopsoas tendon. The iliopsoas tendon stump (IPTS) is at the bottom of the photograph. The iliacus muscle is behind the stump. Part of the hip capsule (HC) is visible at the top of the photograph.

Postoperative rehabilitation

Successful iliopsoas tendon release or lengthening will always produce a loss of flexion strength that usually returns 6 to 8 weeks after surgery. Patients are advised about this situation before surgery, and no active hip flexor exercises are indicated during this period. Quadriceps and hip abductor strength exercises are indicated as soon as the first day after the procedure. There is no restriction of the range of motion with iliopsoas tendon release. Extension stretching exercises are indicated from the first postoperative week to prevent contractures, capsular scarring, and adhesions. Findings of hip arthroscopy should be considered during rehabilitation if microfractures were performed to treat cartilage lesions in load-bearing areas; partial weight bearing should be indicated for 6 weeks. If an osteochondroplasty was performed on the femoral neck for the cam type of femoroacetabular impingement, partial weight bearing should be indicated for 6 to 8 weeks. We do not restrict weight bearing in the case of isolated labral repairs of partial resections.

Results

The reported results of endoscopic iliopsoas release compare favorably with those of open procedures. Regarding the effective treatment of the snapping phenomenon, there are fewer cases of resnapping reported with endoscopic techniques than with open procedures. Hip arthroscopy is also an advantage of endoscopic techniques, which are always performed in conjunction with the arthroscopic examination of the central and peripheral compartments of the hip joint. This provides access for the diagnosis and treatment of intra-articular injuries and peripheral compartment pathologies (e.g., femoroacetabular impingement, loose bodies). The results of iliopsoas tendon release are reported in Table 18-1.

Table 18–1 Results of the Open and Endoscopic Surgical Treatment of Internal Snapping Hip Syndrome

Complications

The most significant complication is the failure of iliopsoas tendon release or lengthening, which results in the need for repeat surgical treatment. Massive heterotopic bone formation after the procedure is also an important complication that requires additional intervention (personal communication, J.W.T. Byrd, Nashville, TN, 2006); this complication can be treated with the resection of heterotopic bone (with either an open or an arthroscopic procedure) and with postoperative irradiation to prevent recurrence.

Annotated references

Allen W.C., Cope R. Coxa saltans: the snapping hip revisited. J Am Acad Orthop Surg. 1995;3:303-308.

Coxa saltans or snapping hip has several causes that can be divided into three types: external, internal, and intra-articular. Snapping of the external type occurs when a thickened area of the posterior iliotibial band or the leading anterior edge of the gluteus maximus snaps forward over the greater trochanter with flexion of the hip. The internal type has a similar mechanism except that it is the musculotendinous iliopsoas that snaps over structures that are deep to it (usually the femoral head and the anterior capsule of the hip). Intra-articular snapping is the result of lesions in the joint itself. The diagnosis of the external and internal types is usually made clinically. Most cases of snapping hip are asymptomatic and can be treated conservatively. However, if the snapping becomes symptomatic, surgery may be required..

Byrd J.W.T. Evaluation and management of the snapping iliopsoas tendon. Tech in Orth. 2005;20:45-51.

Surgical intervention is indicated after the failed conservative treatment of symptomatic internal snapping hip syndrome. Nine cases were treated with the endoscopic release of the iliopsoas tendon at its insertion on the lesser trochanter, which resulted in a 100% success rate for the relief of snapping. More than half of the patients in this study presented with intra-articular pathology..

Cardinal E., Buckwalter K.A., Capello W.N., Duval N. US of the snapping iliopsoas tendon. Radiology. 1996;198:521-522.

Dynamic ultrasound of the hip was performed for 3 patients with snapping hip syndrome. An abnormal jerk was documented in the affected hip as compared with the contralateral side, where a smooth movement of the iliopsoas tendon was observed at the front of the hip..

Dienst M., Seil R., Godde S., et al. Effects of traction, distension and joint position on distraction of the hip joint: an experimental study in cadavers. Arthroscopy. 2002;18:865-871.

This anatomic study analyzed the separation of the femoral head from the acetabulum with the hip in different positions, and it compared traction force and the distention of the hip capsule in the presence of introduced saline..

Dobbs M.B., Gordon J.E., Luhmann S.J., Szymanzki D.A., Schoenecker P.L. Surgical correction of the snapping iliopsoas tendon in adolescents. J Bone Joint Surg Am. 2002;84(Am):420-424.

This study addressed open lengthening in 9 adolescent patients (11 hips). At an average follow up of 4 years postoperatively, only 1 patient had mild recurrent snapping..

Dora C., Houweling M., Koch P., Sierra R.J. Iliopsoas impingement after total hip replacement. J Bone Joint Surg (Br). 2007;89(B):1031-1035.

The reported incidence of iliopsoas impingement after total hip replacement is up to 4.3%. This phenomenon usually occurs in the presence of a prominent acetabular implant anterior rim or as a result of cement extrusion. The authors present a series of 30 hips with psoas impingement after hip replacement. The patients were divided into three groups: Group 1 was treated with conservative treatment, Group 2 underwent iliopsoas open release, and Group 3 experienced acetabular revision. The patients improved significantly more in Groups 2 and 3, with more complications seen in Group 3..

Flanum M.E., Keene J.S., Blankenbaker D.G., Desmet A.A. Arthroscopic treatment of the painful “internal” snapping hip: results of a new endoscopic technique and imaging protocol. Am J Sports Med. 2007;35:770-779.

This was a report of about 6 patients treated with endoscopic iliopsoas tendon release at the lesser trochanter. At 12 months of follow up, the authors reported a 100% success rate..

Gruen G.S., Scioscia T.N., Lowenstein J.E. The surgical treatment of internal snapping hip. Am J Sports Med. 2002;30:607-613.

This report presents 11 patients (12 hips) treated with iliopsoas lengthening that involved the use of an ilioinguinal intrapelvic approach. At an average follow up of 3 years, 100% of the patients were asymptomatic..

Harper M.C., Schaberg J.E., Allen W.C. Primary iliopsoas bursography in the diagnosis of disorders of the hip. Clin Orthop Relat Res. 1987;221:238-241.

A technique of primary psoas bursography under fluoroscopy is described. Filling the bursa with contrast material allowed for the observation of the movement of the iliopsoas musculotendinous unit across the front of the pelvis during motion of the hip..

Ilizaliturri V.M.Jr, Mangino G., Valero F.S., Camacho-Galindo J. Hip arthroscopy of the central and peripheral compartment by the lateral approach. Tech Orthop. 2005;20:32-36.

A technique for positioning the patient in the lateral decubitus position for hip arthroscopy is presented. Avoiding compression injuries during traction and maintaining the mobility of the setup without traction for access to the peripheral compartment are emphasized. Accessory portals for accessing the hip periphery are described..

Ilizaliturri V.M.Jr, Villalobos F.E., Chaidez P.A., Valero F.S., Aguilera J.M. External snapping hip syndrome: treatment by endoscopic release of the iliopsoas tendon. Arthroscopy. 2005;21:1375-1380.

An endoscopic technique to release the iliopsoas tendon at the lesser trochanter to treat internal snapping hip syndrome is presented. Seven hips were treated successfully with the use of this technique. More than half of the patients presented with intra-articular pathology..

Jacobson T., Allen W.C. Surgical correction of the snapping iliopsoas tendon. Am J Sports Med. 1990;18:470-474.

This report presents 18 patients with 20 symptomatic snapping hips who were treated with open lengthening with a step- cutting technique. At a mean postoperative follow up of 25 months, 6 patients had recurrence of mild snapping, and 2 hips required reintervention for painful snapping..

McCulloch P.C., Bush-Joseph C.A. Massive heterotopic ossification complicating iliopsoas tendon lengthening. Case report. Am J Sports Med. 2006;34:2022-2025.

A 25-year-old male elite college soccer player was treated with an open lengthening of the iliopsoas tendon after the failure of conservative treatment for internal snapping hip syndrome. Three months postoperatively, the patient complained of mild pain and a limited range of motion; massive heterotopic bone formation was diagnosed at the area of the lesser trochanter. Six months postoperatively, the ectopic bone formation was removed; it recurred 6 months later, another operation was performed to remove the heterotopic bone, and the patient was irradiated. No further recurrence was reported..

Miller F., Cardoso Dias R., Dabney K.W., Lipton G.E., Triana M. Soft-tissue release for spastic hip subluxation in cerebral palsy. J Pediatr Orthop. 1997;17:571-584.

Children with spastic hip subluxation as a result of cerebral palsy were treated with a standard protocol that focused on the early detection of the subluxation with the use of physical examination and anteroposterior pelvis radiographs. Using limited hip abduction of 30 degrees or less and subluxation of at least 25% migration percentage as indications, patients underwent open adductor and iliopsoas lengthenings with immediate postoperative mobilization and no abduction bracing. The protocol was applied to 74 children with a mean age of 4.5 years, and 147 hips were surgically addressed. Of these hips, initially, 20% were normal (migration percentage, <25%); 52% were mildly subluxated (migration percentage, 25% to 39%), 22% were moderately subluxated (migration percentage, 40% to 59%), and 6% were severely subluxated (migration percentage, ≥60%). At a final postoperative follow-up evaluation at 39 months, 54% of these hips were classified as good (migration percentage, <25%), 34% were considered fair (migration percentage, 25% to 39%), and 12% were thought to be poor (migration percentage, ≥40%). Of this patient population, 69% were nonambulators, and their outcomes were not statistically different from those of children who could walk. No child developed an abduction contracture or a wide-based gait that required treatment. With early detection and the application of this treatment algorithm, 80% of children with spastic hip disease should have good or fair outcomes. Longer follow-up times will be needed to determine how many children will require bony reconstruction to maintain stable and located hips when they have finished growing..

Tannast M., Siebenrock K.A., Anderson S.E. Femoroacetabular impingement: radiographic diagnosis—what the radiologist should know. AJR Am J Roentgen. 2007;188:1540-1552.

The purpose of this article is to describe the radiographic criteria that indicate the two types of femoroacetabular impingement. In addition, potential pitfalls in pelvic imaging that involve femoroacetabular impingement are shown..

Taylor G.R., Clarke N.M. Surgical release of the “snapping iliopsoas tendon.”. J Bone Joint Surg Br. 1995;77(Br):881-883.

This is a report about 16 open surgical releases that involved a medial approach. At a mean of 17 months of follow up, snapping was resolved in 10 hips, occasional painless snapping was present in 5 hips, and the condition was unchanged in 1 hip..

Wettstein M., Jung J., Dienst M. Arthroscopic psoas tenotomy. Arthroscopy. 2006;22:907. e1–4

This article describes a surgical technique that involves access to the iliopsoas bursa from the hip periphery without traction via an anterior hip capsulectomy. The iliopsoas tendon is exposed through the anterior hip capsulectomy and then released, thus preserving the iliacus muscle. Nine patients were reported as having a 100% success rate at a minimum follow up of 3 months..

Winston P., Awan R., Cassidy J.D., Bleakney R.K. Clinical examination and ultrasound of self-reported snapping hip syndrome in elite ballet dancers. Am J Sports Med. 2007;35:118-126.

A snapping hip questionnaire was completed by 87 unselected elite ballet dancers. Twenty-six of these individuals (50 hips) were further examined by clinicians. Ninety-one percent reported snapping hip (80% bilateral), 58% had associated pain, and 7% had taken time off from dancing for this reason..

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