Investigating the painful Total Hip Replacement

 

It is important to note there may be more than one reason for pain/problems present. It is important to identify all causes. A careful history and physical examination is therefore especially important.  Investigations are usually performed; these will include x-rays and blood tests.

The following are some of the tests and scans you may need to undergo:

  • Blood tests can sometimes rule out infection in painful joint replacements.

  • X-rays of the hip can help assess bone loss.

  • Bone scan, looking for signs of loosening or infection.

  • CT scans are useful in assessment of alignment and bone damage.

  • MRI scans are useful for assessing muscle damage and for ‘metal on metal disease’.

  • Ultrasound scans, when performed by experienced musculoskeletal radiologists, can provide an excellent dynamic assessment of tendon function and bursitis; but are usually used to correctly target diagnostic/therapeutic local anaesthetic +/- steroid injections.

  • Examination under anaesthesia is useful for assessing positions of instability.

  • Aspiration is useful to test for infection.

  • Injecting local anaesthetic into the hip joint is useful to identify if the cause of the pain is inside or outside the hip joint.

Causes of groin pain after hip replacement:

  • Psoas impingement is a relatively common cause of groin pain after hip replacement (4-5%). Mr Ashworth has specialised in arthroscopic treatment of this condition as a day case procedure. He has reported a high success rate in resolving pain caused by psoas tendon impingement over the front of the acetabular component of a hip replacement.

 

  • Ischio-femoral impingement is a rare cause of pain due to the hip being too narrow/close to the pelvis and the lesser trochanter trapping the quadratus-femoris muscle against the ischium. Once the diagnosis is confirmed it is possible to treat this arthroscopically as a day case.