The following is a summary of Enseki, K et al (2014). Nonarthritic hip joint pain – clinical practice guidelines. JOSPT, 44, 6, A1-A32.
Intra-articular conditions, other than OA, that can lead to hip pain are discussed below. This does not include extra-articular soft-tissue conditions, such as trochanteric pain syndrome, adductor strain, psoas tendinopathy, etc. Many of the following conditions do have the potential to progress to hip OA.
Common non-articular hip conditions include:
- Femoroacetabular impingement
- Labral tears
- Structural instability
- Osteochondral lesions
- Ligamentum teres tears
- Loose bodies.
Femoroacetabular impingement (FAI):
This will be covered in more detail in a subsequent newsletter. Bony impingement arises secondary to genetic & possibly developmental factors. ‘Cam’ impingement is more common in young males, and ‘pincer’ impingement is more common in females. FAI is thought to be a common cause of labral tears and later hip OA. Click here for more information.
Labral Tears:
The role of labral tears in hip symptomatology is controversial, as studies have found the incidence to be up to 90% in the general population. However the labrum is a potent source of hip pain, and pathology has been found to be higher in the symptomatic hip & in certain athletic populations. Click here for more information.
Structural instability:
Causes of this include hip dysplasia, general ligamentous laxity, increased femoral neck inclination angle, altered femoral version, and traumatic ligament insufficiency. Symptoms may include difficulty with pivoting, pain on prolonged weight-bearing, feelings of the joint slipping and general muscle ache / fatigue.
Ligamentum teres tears:
While rare, there is some evidence that tears to this ligament are found more commonly in those with hip pathology. Tears are found in around 8% of subjects having hip arthroscopy. The ligament may be vulnerable during excessive flexion combined with external rotation, or extension combined with internal rotation. Tearing may lead to microinstability, and subsequent labral &/or chondral degeneration.
Chondral lesions:
Chondral defects may arise after trauma (such as a lateral blow to the greater trochanter), or due to dysplasia, FAI or joint laxity. These lesions are found more commonly in hips with labral tears.
Loose bodies:
These may be ossified or non-ossified, and may be present secondary to instability/dislocation, osteochondritis dissecans, or synovial chondromatosis.
Differential Diagnosis:
Some common conditions which can mimic hip joint pain include:
- Spinal, nerve root or SIJ referral
- Pubic symphysis dysfunction.
- Iliopsoas tendinopathy / bursitis
- Adductor strain
- Obturator internus strain
- Inguinal or sports hernia
- Osteonecrosis of the femoral head
- Stress fracture
- Gynecological conditions
- Nerve entrapments – lateral femoral cutaneous, obturator.
Less common conditions to be aware of include:
Avulsion of sartorius or rectus femoris; myositis ossificans; hypertrophic ossification of the hip; neoplasm; Perthes disease; slipped capital femoral epiphysis; osteomyelitis; RA; septic arthritis; prostatitis; psoas abscess.
