Does Hip Resurfacing limit ROM more than a THR?
| Dr. Bose
One must remember that with a resurfacing or a THR – one is not aiming to give supra normal movement. One is merely trying to restore normal movement present before the onset of hip arthritis. The head- neck offset is an important determinant of ROM. This is restored by a properly done resurfacing even in patients who have a poor head neck offset as in FAI ( femoro – acetabular impingement. Hence full restoration of ROM is consistently possible in a resurfacing. A big ball THR has an abnormally high head neck offset due to the thin neck. Thus in theory a big ball THR can produce supra normal movement . However this is neither desirable or feasible in clinical practise as the head neck offset is only one of the factors influencing ROM. Other factors like soft tissue tension come into play. If one goes on making the neck thinner progressively and the head progressively larger — it is wrong to imagine that this will translate progressively into continued increase in Range of Movement. In a badly done resurfacing, impingement can occur and this will lead to abnormal wear pattern and in extreme cases can be seen on x-rays. A properly done Resurfacing will definitely match any type of THR for the ROM. It is moot point that a Big ball THR will be more forgiving for surgical errors than a resurfacing in respect to ROM. With best regards Vijay bose chennaiInformation obtained by Vicky Marlow Freelance Patient Advocate Volunteer 2008 |