Snapping Hip Syndrome) Thomas G

12 Arthroscopic Iliopsoas Release for Coxa Saltans Interna (Snapping Hip Syndrome) Thomas G. Sampson

oxa saltans interna is a hip syndrome resulting the splits. Some report a hyperextension injury of the in the iliopsoas tendon snapping pathologically hip. Associated with the injury, the patient may ex- Cover structures beneath it, causing a loud au- perience the onset of popping or hip clicking that in- dible click or clunk, which may be associated with tensifies over time to a consistent snapping sensation pain. It is thought the most common involved struc- that may be heard by anyone around them. The ini- ture it courses over is the iliopectineal eminence (Fig- tial pain from the injury typically never resolves, and ure 12.1); however, other intraarticular structures may the snap hurts. be large loose bodies and exostoses. The differential Normal walking is not painful, but pain may limit diagnosis must rule out labral tears, synovial chon- sports or dancing that involves hip flexion. With the dromatosis, and abnormal shapes of the femoral head patient supine, the patient can reproduce the snap as from an old slipped capital femoral epiphysis or hip he or she flexes and extends the hip. The examiner dysplasia and acetabular retroversion. can eliminate the snap by applying pressure over the The iliacus and the psoas fuse to become one mus- anterior hip capsule, which restricts the tendon’s culotendinous unit as they pass in a sulcus between movement. Such a maneuver is diagnostic for coxa the anteroinferior iliac spine and the iliopectineal em- saltans interna. inence (Figure 12.2). The tendon courses over the anterior hip capsule as it passes posteriorly in the iliopsoas bursa to insert onto the lesser trochanter (Figure IMAGING 12.3). The tendon assumes a lateral position on the iliopectineal eminence when the hip is in flexion, ab- Plain radiographs are usually normal and may be help- duction, and external rotation. As the hip is moved ful to identify exostoses or a spur on the lesser into extension, adduction, and internal rotation, the trochanter as well as dysplasia or impingement. Mag- tendon moves from lateral to medial; however, the netic resonance imaging (MRI) is best to document musculotendinous portion remains in the groove.1 any thickening of the iliopsoas tendon or fluid in the The symptomatic snapping hip is caused by the bursa. Iliopsoas bursography may demonstrate the back-and-forth movement over the anterior hip cap- outline of the tendon as it snaps over the hip capsule sule and femoral head. The etiology may be a hyper- and is a dynamic test.3 Elimination of the pain by a extension injury to the hip capsule or tendon itself. lidocaine injection in the bursa is a positive diagnos- Other causes may be from exostoses on the acetab- tic test. ular rim or femoral head as well as the lesser trochanter.2 The iliopsoas bursa may also become in- flamed or hypertrophic, leading to the condition. Of SURGICAL TREATMENT note, the iliopsoas bursa is the largest bursa in the body, measuring 7 cm long and 4 cm in width. The classic open surgical approach is through an 8- to 10-cm groin incision, protecting the neurovascular 4,5 CLINICAL DIAGNOSIS structures and lengthening the tendon 2 cm. We have developed an arthroscopic approach in which the The patient presents with a vague history of an injury iliopsoas tendon is either partially or completely re- that may have felt like a groin sprain or of having done leased from the lesser trochanter. 189 190 THOMAS G. SAMPSON

Iliopectineal line

FIGURE 12.1. The iliopsoas courses over the iliopectineal line.

Technique epinephrine. The skin is incised with a no. 11 blade, and the cannulated scope sheath is passed over the The patient is positioned for the lateral approach (see 6,7 wire into the bursa under fluoroscopic control. The Chapter 9). After the hip has undergone a diagnos- inflow is started to distend the bursa. tic arthroscopy, the traction is completely released. The foot is maximally externally rotated, thus bring- ing the lesser trochanter to an anterior position and is Instrument Placement viewed orthogonal with the C-arm fluoroscope (Fig- ure 12.4A,B). A second AI portal is created in the same manner and Two additional safe portals are needed: the an- a switcher stick is placed. The iliopsoas tendon is pal- teroinferior (AI) and far anteroinferior (FAI). Origi- pated while viewing with a 30-degree arthroscope nally, we used the anteroinferior medial (AIM) and AI (Figure 12.6A,B). It may be necessary to clear bursa or (Figure 12.5A,B). muscle to view the tendon. A long cannula may aid in passing instruments or to maintain outflow to pre- vent distension. Arthroscope Placement An intracath is directed from the AFI portal to a point The Release just proximal to the lesser trochanter into the iliopsoas bursa. A Nitanol wire is passed through the in- The iliopsoas tendon is sectioned with a radiothermal tracath and the skin is anesthetized with marcaine/ cutter so as to coagulate bleeders as it is cut. We have CHAPTER 12: ARTHROSCOPIC ILIOPSOAS RELEASE FOR COXA SALTANS INTERNA 191

FIGURE 12.2. The iliacus and psoas muscles form a conjoined tendon that inserts onto the lesser trochanter.

Iliacus muscle

Psoas muscle

Conjoined tendon

used the ArthroCare devices (ArthroCare, Sunnyvale, CA) and the Mitek VAPR (Ethicon, Someville, NJ) with good success. Starting from the medial side of the tendon, it is sectioned working laterally (Figure 12.7A–D). Whether to do a partial or complete release is based on clinical judgment. The goal is to lengthen the musculotendinous unit, and a partial release ac- complishes this. If there is pathology in the tendon such as a bifid or trifid appearance (Figure 12.8) or if the lesser trochanter has a spur, a complete release is recommended.

POSTOPERATIVE TREATMENT

The portals are sutured, and a thigh dressing is applied with compression. Crutches, with partial weight bear- ing, are used until the patient has good control of the hip (usually 2 to 3 weeks). Flexion exercises are begun FIGURE 12.3. The iliopsoas lies anterior to the hip capsule and moves lateral with hip flexion, abduction, and external rotation. As immediately, and strength returns in 3 to 6 weeks af- the hip is extended, adducted, and internally rotated, the tendon ter a partial release and 3 to 6 months after a com- moves in a medial direction. 192 THOMAS G. SAMPSON

B B FIGURE 12.6. (A) Arthroscopic view of the iliopsoas tendon inserting onto the lesser trochanter. (B) After partial release. FIGURE 12.4. (A) Fluoroscopic view with the C-arm giving an orthogonal view of the lesser trochanter while the hip is externally rotated and instruments are positioned. (B) The arthroscope is placed through the far anteroinferior portal and the cutting instrument through the anteroinferior portal.

A B FIGURE 12.5. (A) Patient in the lateral decubitus position, the C-arm in place. The portals are posterolateral (PL), anterolateral (AL), anterior (A), anteroinferior (AI), and far anteroinferior (FAI). (B) Technique using the FAI and the anteroinferior medial (AIM) portals (the original method). CHAPTER 12: ARTHROSCOPIC ILIOPSOAS RELEASE FOR COXA SALTANS INTERNA 193

A B

C D FIGURE 12.7. (A) Sprained iliopsoas tendon inserting onto the lesser trochanter. (B) After partial release with a radiothermal wand. (C) The iliopsoas has been completely released. Note the large bursal space. (D) The probe is on the lesser trochanter (LT). The iliopsoas tendon (IT) is retracted after its release in the iliopsoas bursa (IB).

plete release. Occasionally, a nonpainful mild pop may turn of their muscle strength by 3 months. All had be present for 3 to 6 months. resolution of their snap, and 94% had good to excel- lent results and pain relief.

RESULTS CONCLUSION Since 1993 we have released 35 iliopsoas tendons for snapping hip syndrome. All were successfully viewed Arthroscopic iliopsoas tendon release has been de- and released using the arthroscopic technique. There scribed. It is a safe and effective way to treat coxa were two complications, one with neuropraxia of the saltans interna and is reproducible. The results are bet- lateral femoral cutaneous nerve and one with 4/5 ter than the results of open surgery and have fewer flexor weakness at 6 months. All the rest had full re- complications. 194 THOMAS G. SAMPSON Acknowledgment. I would like to thank James M. Glick, MD, for his contributions to this chapter.

References 1. Allen WC, Cope R: Coxa saltans: the snapping hip revisited. J Am Acad Orthop Surg 1995;3(5):303–308. 2. Schaberg JE, Harper MC, Allen WC: The snapping hip syndrome. Am J Sports Med 1984;12(5):361–365. 3. Harper MC, Schaberg JE, Allen WC: Primary iliopsoas bursography in the diagnosis of disorders of the hip. Clin Orthop 1987; 221:238–241. 4. Dobbs MB, Gordon JE, Luhmann SJ, et al: Surgical correction of the snapping iliopsoas tendon in adolescents. J Bone Joint Surg [Am] 2002;84(3):420–424. 5. Jacobson T, Allen WC: Surgical correction of the snapping iliopsoas tendon. Am J Sports Med 1990;18(5):470–474. 6. Glick JM, Sampson TG, Gordon RB, et al: Hip arthroscopy by the lateral approach. Arthroscopy 1987;3(1):4–12. 7. Sampson TG, Fargo LA: Hip arthroscopy by the lateral approach: technique and selected cases. In: Byrd JW (ed). Operative Hip Arthroscopy. New York: Thieme, 1988: FIGURE 12.8. An example of a trifurcated iliopsoas tendon. 105–121.