In the last years there has been a new enthusiasm for the use of resurfacing THA. With the experience gained we have learned that there are some absolute and relative contraindications (i.e. inflammatory arthritis, AVN, poor bone stock, sever distortion of thehip anatomy, varus neck, small head). In order to over come those contraindications and in the light of the fact that reliable long-term effectiveness of hip replacement in young active patients remains problematic we have started to use metaphyseal prosthesis. The metaphyseal implant minimizes bone resection, violets less the native bone of the proximal femur, has favorable remodeling characteristics and facilitate revision once needed. Due to its small size and the varus orientation limited or minimal approach is easy and safe.
Material and methods: The Mayo Conservative hip was used in 65 patients during the years 2000–2005. 3 patients were lost to follow-up and were not included. Avrage age was average 44.6. The basic etiology was osteoarthritis (38), AVN (12), RA (4), DDH (4), distorted proximal femur (2) and revision after failed resurfacing THA (2). Follow-up was 6–58 months (average 45.2). XR were taken each time and clinical examination was done, gait pattern was noted as well as ROM and muscle strength Patient satisfaction was noted based on their function ability, using of waking aids and the amount of pain.
Results: We had 2 cases of intraoperative proximal femur crack that were treated with tension wire; no other intraoperative complication was noted. None of the patients developed infection and no one had dislocation. Pain was reduced from sever in all patients to mild or none in 90% (56/62), moderate in 8% (5/62) and sever in one patient (2%). Pre operative ROM was reduced and painful. Painless, near normal ROM was achieved in all patients and only 5 needed walking stick (all of them between 6–12 month post operative). Follow-up XR showed no sign of bone subsidence or loosening
Conclusions: Metaphyseal prosthesis can be a good alternative to resurfacing arthroplasty. Our experience show that the procedure is safe and medium term results are good to excellent.
