Things that go ‘click’ in the hip

While ‘clicky hips’ are often associated with acetabular dysplasia in infants, there are many things that go ‘click’ in the adult hip. Most of these are innocuous, but sometimes they are painful or of concern to the owner of the noisy hip. Sources of snapping or clicking in the hip may include:

• the psoas or iliopsoas tendon
• the rectus femoris proximal tendons
• the iliotibial band
• the gluteus maximus
• ischiofemoral impingement
• a subluxing proximal hamstring tendon
• a chondral (cartilage) flap
• a labral tear
• a loose body or fragment
• lumps in the joint lining - synovial proliferation (e.g.pigmented villonodular synovitis)
• synovial folds or plicae (natural folds in the joint lining)
• joint cavitation

Being aware of the different causes of clicking in and around the hip will allow you to reassure your patient and where necessary, develop an informed intervention for managing painful clicking. In medical terminology, snapping hip is often referred to as coxa saltans. Coxa is latin for “hip,” and saltans, means “jump.” Snapping or clicking may emanate from either outside the joint (extraarticular) or inside the hip joint (intraarticular). Let’s explore some of the possible sources.

Extra-articular snapping hip

Internal snapping hip or coxa saltans, anterior snapping hip, snapping hip syndrome, iliopsoas snapping hip

Extra-articular snapping at the anterior hip has a variety of names, including internal snapping or internal coxa saltans, anterior snapping hip, snapping hip syndrome or iliopsoas snapping hip¹. It is also sometime referred to as ‘dancer’s hip’ due to the high prevalence of anterior snapping hip in the dance population².  The term ‘internal snapping’ is a little misleading as this may be interpreted as intra-articular snapping, but it refers to snapping outside the anterior aspect of the hip joint. This form of snapping most commonly occurs during an eccentric hip flexor action, lowering the leg from a flexed and/or abducted hip position.

Internal/anterior snapping is most commonly associated with the iliopsoas or psoas tendon, depending on the particular location and cause of the snap. There are varying theories regarding the cause of iliopsoas tendon snapping. Most commonly it is believed that the tendon snaps over a prominence on the pelvic brim – the iliopectineal eminence, or over the femoral head¹. The iliacus and psoas tendons are usually still distinct at the anterior hip and pelvic brim and the tendon that snaps here is the psoas tendon. Others have demonstrated that the psoas tendon slips around an active iliacus muscle, allowing abrupt contact of the tendon against the pubic bone³. Snapping of the iliopsoas tendon more distally, may be due to a bifid tendon of insertion⁴. This is an anatomical variation that may result in snapping as the tendons move around each other. Snapping of the iliopsoas tendon at the lesser trochanter has also been reported⁵.

Iliopsoas snapping is usually attributed to tightness or overactivity of the iliopsoas, with treatment involving stretching or manual or surgical ‘release’. There are many unsubstantiated assumptions here and optimal management of painful iliopsoas snapping remains contentious but beyond the scope of this current blog.

While the psoas or iliopsoas tendon is the most common source of anterior snapping at the hip, the rectus femoris tendons have also been implicated. The rectus femoris indirect or reflected head may snap against the femoral head or calcific deposits in the direct head may snap against adjacent structures⁶.

External snapping hip or coxa saltans, lateral snapping hip, iliotibial band snapping

The other most common source of extraarticular snapping is that of the iliotibial band or gluteus maximus snapping around the greater trochanter⁷. This is referred to as external snapping hip, external coxa saltans, lateral snapping hip or more specifically, iliotibial band (ITB) snapping. Patients may report the snapping occurs with loaded weightbearing tasks such as squatting, bending forward, walking or stairclimbing. Some will report that their hip dislocates, subluxes or ‘pops out’. This is important to address, as this belief can perpetuate fear avoidant behaviours. When asked to reproduce the hip ‘dislocation’, the patient will usually be able to demonstrate in standing by simply shifting their pelvis posterolaterally. The ITB shifts anteriorly over the greater trochanter, causing a loud snap or clunk which can be understandably concerning.

If the snap is not associated with lateral hip pain, reassurance may be sufficient. If the snap is associated with pain and/or functional difficulties in weightbearing tasks, femoropelvic control and abductor muscle function are targets for intervention.

Snapping or clicking associated with ischiofemoral impingement

Audible snapping of the ITB during gait is generally easily palpable over the greater trochanter. If you cannot palpate any physical translation of the ITB at the greater trochanter during a mid to late stance phase click, be suspicious of ischiofemoral impingement. Ischiofemoral impingement refers to impingement of soft tissues between the lateral ischium and the lesser trochanter⁸. Quadratus femoris sits in the ischiofemoral space and may become painful and oedematous due to repetitive impingement between the bones. The tendons inserting into the ischium (hamstrings) and lesser trochanter (iliopsoas) may also become sources of nociception due to the repetitive friction.

Ischiofemoral impingement is not always accompanied by an audible click, but in some people the noise is easily heard as the bones move past each other in mid-late stance phase. This will not be palpable, but you can test your theory with the long stride walking test⁹, where symptoms worsen with large strides and reduce with small strides or walking with a wider base. Ischiofemoral impingement may be structural, functional or both, with non-surgical management aiming to reduce impingement through load management education, movement training and exercise therapy.

Subluxing hamstring tendon, snapping bottom

A relatively rarer source of external coxa saltans is a subluxation of the hamstring tendon, also referred to as ‘snapping bottom.’ This condition may be associated with proximal hamstring tendinopathy or partial tear of the lateral portion of the hamstring origin¹⁰. Snapping is most likely to occur when the hamstrings are on tension, such as in forward bending, or when the tendon is pulled laterally in FABER-type hip positions. Non-surgical treatment includes load management for the proximal hamstring tendinopathy, with specific attention to load sharing in forward leaning and controlling sustained or repetitive exposure to subluxation positions.

Optimising health of the hamstring tendons, and hip extensors more generally, through a targeted exercise program can be useful. If non-surgical intervention is unsuccessful in reducing pain and restoring function, surgical intervention includes partial tenotomy or tenodesis (tendon transfer) of the damaged portion of the tendon.