A conservative femoral replacement for total hip arthroplasty

Abstract

Between 1985 and 1993, 146 patients (162 hips) had total hip replacement (THR) using a conservative uncemented femoral component. The mean age of the patients was 50.8 years and the mean follow-up was 6.2 years (2 to 13). One patient was lost to follow-up, one died within two years of surgery and one had a revision procedure after a fracture sustained in a road-traffic accident. For the remaining 159, Kaplan-Meier survival analysis was calculated for the incidence of revision because of mechanical loosening or osteolysis. Survival without mechanical loosening at both five and ten years was 98.2%. Survival without osteolysis was 99% at five and 91% at ten years. The Harris hip score improved from a mean of 66.3 before to 90.4 at follow-up. Of particular note is the lack of thigh pain in this group. Radiological analysis showed that 139 stems (88%) had no measurable subsidence, 8 (5%) had less than 2 mm and 12 (7%) had more than 2 mm. Two of the eight and one of the 12 were revised for mechanical loosening. Nine hips were revised for late loosening associated with osteolysis. No reaming of the femoral canal was associated with statistically significant less blood loss compared with a comparable control group of uncemented implants (p < 0.0001). Our study suggests that using a conservative femoral implant does not protect against wear debris but the reliable mechanical stability (98.2%) makes this an attractive design of implant particularly for young patients.

Clinical results of the Metha short hip stem: a perspective for younger patients?

“…As the implant was introduced in 2005, the follow-up period was shorter than in other studies of short stem implants, 3,4,8,18 and comparable to recent clinical results of an average follow-up of 2,4 years of the same implant design. 14 Our overall survival rate was over 98% to the time of follow-up.…”

“…2,3,7,9,17 These prostheses can be implanted using a less- or minimally-invasive surgical approach to avoid muscle damage, preserve proximal bone, and to start rehabilitation earlier. 3,9,18 A proximal anchorage of short stems may lead to the application of more physiological load. 2,7,9,18 This was demonstrated by Morrey et al .…”

“…in their 7-year survival rates of the Mayo short stem of 98%. 3 The design and anchoring principle of the Metha short stem anchorage is similar to the Mayo short stem. They simply differ in the proximal shape of the implant, the surface coating and the modular set-up.…”

Changes in strain patterns after implantation of a short stem with metaphyseal anchorage compared to a standard stem: an experimental study in synthetic bone

“…However, contemporary short stem devices have a completely different principal design. Due to encouraging results of the Mayo stem – one of the first short stem implants – with a 94% survival rate after 6.2 years, 2 other short stems have been developed 29 . Thorey et al .…”

The Mayo conservative hip: complication analysis and management of the first 41 cases performed at a University level 1 department

“…Survival rates without revision of a femoral short-stem component and aseptic loosening have been reported as 98% after 6.8 years in 162 treatments [1], 99% in 155 cases after 6.2 years [21], 100% after 5.2 years [22] and 95, 2% in the current study.…”