Koen De Smet ANSWER/ANTWOORD] In the US for long they were doing hemiresurfacings because full resurfacings were not working well and the Metal on Metal resurfacing was not FDA approved yet. The results indeed are not so good. The hipscores after a time are certainly not perfect, not what we can get with a total resurfacing!
The hemiresurfacing also is only kept for people with an avascular necrosis of the hip, not for any other condition, so the indication is not so big. The problem in these cases is that after time the metal head that is resurfaced will give osteoarthritis symptoms because it is wearing out the cartilage of the acetabulum. If the patient has had a hemiresurfacing that is a component that matches with a total MOM resurfacing and the size of the head is not put too big, they can have a full resurfacing done with the head implant kept on! Unfortunately this is not always possible and most of the time not possible.!
There are indeed cases that can stay long with this device, hemiresurfacing, but it is certainly the minority.
Looking into the indications to do a hemi, avascular necrosis is known to be a condition that gives the less good results in any prosthetic implant. (In my series with resurfacing and ceramic on ceramic in young people I can not state or proof this)
Koen De Smet
Anca Medisch Centrum – Anca Medical Center GHENT