In snapping hip syndrome there is an audible snap or click that occurs in or around the hip. Snapping hip syndrome may be called
- External – Snapping of the iliotibial band or gluteus maximus over the greater trochanter
- Internal – Snapping of the iliopsoas tendon
The condition occurs most often in individuals aged 15-40 years and affects females slightly more often than males.
Causes of Snapping Hip Syndrome
Read Anatomy of Pelvis
Read Anatomy of Hip
At and around greater trochanter, there are
- Tendons of gluteus muscles
- Tensor fascia lata
- Greater trochanteric bursa
- Iliotibial band.
The most common cause of a snapping hip is the iliotibial band snapping over the greater trochanter which may be associated with trochanteric bursitis and increased hip varus.
[Iliotibial band is a ligament that originates from the iliac crest and inserts on the lateral proximal tibia. With sudden loading, the hip is flexed and the iliotibial band moves anteriorly followed by the tendon snapping backward as hip extends]
The gluteus maximus inserts on the iliotibial tract and gluteal tuberosity of the femur. During extension of the hip, the distal border may snap over the greater trochanter of the femur.
The psoas and iliacus muscles originate from the lumbar spine and pelvis and converge to form the iliopsoas muscle, which inserts onto the lesser trochanter. The iliopsoas muscle passes anterior to the pelvic brim and hip capsule in a groove between the anterior inferior iliac spine laterally and iliopectineal eminence medially.
Iliopsoas tendon snapping may occur over the iliopectineal eminence, hip capsule, or the lesser trochanter when a flexed, abducted, and externally rotated hip is extended.
Snapping hip syndrome is usually the result of repetitive overuse. It may also develop following injury leading to subsequent bursitis, tendinitis, or biomechanical changes.
Alteration of general biomechanical may lead to anterior pelvic tilt which in effect may cause patellofemoral knee pain. This is discussed in more detail here.
Posterior snapping hip syndrome is rare and is caused by movement of the long head tendon of the biceps femoris over the ischial tuberosity.
Clinical Presentation of Snapping Syndrome
The patient complains of snapping or sensation of dislocating hip. The symptoms might be present for months or years before the patient seeks medical help. The location may be described as lateral, (indicating the iliotibial band or gluteus maximus) or deep in the groin (indicating the iliopsoas tendon). Patients reporting anterior groin pain usually note that the pain is dull or aching in nature and is exacerbated by extension of the flexed, abducted, and externally rotated hip.
In case of iliotibial band or external snapping hip, the snapping may be visible. In cases of internal snapping hip, the snap may be audible. The snapping may be painful or pain free.
On examination, gait should be analyzed. If there is iliopsoas tendinitis, the patient may have a flexed knee in the heel-strike and midstance phases of gait.
Patients may have tenderness over the proximal iliotibial band, lateral margin of the gluteus maximus, trochanteric bursa or at the insertion of iliopsoas.
Anterior pelvic tilt may be found in cases of internal snapping hip syndrome [tight iliopsoas] which may lead to hamstring tightness.
Reproduction of snapping should be observed.
- External snapping hip syndrome – Passive internal and external rotation of the hip with the patient in the side-lying position.
- Internal snapping hip syndrome – Extension of the flexed, abducted and externally rotated hip.
Patient should be observed for deformities like genu recurvatum, knee and hip flexion contracture, foot overpronation, leg length inequality etc.
Differential Diagnoses
- Femoral Head Avascular Necrosis
- Iliopsoas Tendinitis
- Iliopsoas Bursitis
- Iliotibial Band Syndrome
Laboratory Studies
Laboratory studies are not required for diagnosis but may aid in ruling out certain conditions
Imaging
Xrays are almost always normal. They may help to rule out bony conditions.
Ultrasound is able to visualize the structural changes in anatomy and also provide the assessment of function.
Bursography [Injecting the iliopsoas bursa with a contrast agent and under fluoroscopy] may reveal aggravating motions of the hip.
MRI may reveal the pathological entity and differentiate between different causes.
Hip arthroscopy may be of benefit for ruling out labral tears.
Treatment
Relative rest, ice application and NSAIDs are the initial treatments in the acute phase of the problem.
In addition, the patient is put on physical therapy to correct the mechanical abnormalities.
The treatment of internal snapping hip syndrome is similar to the treatment of iliopsoas tendinitis and bursitis.
In the rehabilitation period, the patient is constantly evaluated and the treatment, including physical therapy , are directed by examination findings. Patients are cautioned to eliminate repetitive motion activities like running, cycling until they are relatively asymptomatic.
Muscle weakness, tightness, or both in the thigh or pelvis are addressed with a strengthening and stretching program. Overpronation may require a foot orthotics. Leg length deformities commonly require a lift in the shoe.
Surgical Intervention
Though it is rarely needed, surgery is indicated in the patients with persistent pain associated with a snapping hip that did not respond to conservative therapy.
For External Snapping Syndrome
- Resection of the posterior half of the iliotibial tract at the insertion site of the gluteus maximus, with excision of the trochanteric bursa.
- Elliptical resection of a portion of the iliotibial band over the greater trochanter, with the removal of the trochanteric bursa.
- Z-plasty of the iliotibial band,
- Endoscopic release of the gluteus maximus tendon for snapping due to gluteus maximus tendon.
Internal Snapping Hip
PThe partialor complete release of iliopsoas tendon, either open or arthroscopically
Once symptoms have decreased and the patient is able to return to daily and athletic activities, a maintenance program of stretching and strengthening can be done.
Patients may return to activities as tolerated. The return to sports activities is safe once the patient is free from pain and is capable of demonstrating sports-specific activities.
For further prevention of snapping hip syndrome flexibility and strength in the hip and pelvis.
