Abstract
The modern era of hip resurfacing was initiated over two decades ago to address the poor results of existing hip replacement devices in young patients. High failure rates have been reported with certain resurfacings. This is a 1 to 17-year review of a single surgeon series of resurfacings in patients under the age of 50 years.
Between July 1997 and June 2014, 3627 hip resurfacing arthroplasties were implanted at our Centre in 2878 patients using a posterior approach. Of these 863 patients (1063 hips, 754 in men and 309 in women) were under the age of 50 years at the time of operation. They were followed up with postal questionnaires for up to 10 years through independent Outcomes Centres initially and are currently followed up by our own Centre.
18 patients (24 hips) died 5.9 (0.02 – 11) years after surgery due to unrelated causes, including one patient (1 hip) who was revised and died 5 years after revision. Mean follow-up is 11.9 years (0.8 to 17.8 years). There were 22 revisions altogether (2.1%) at a mean of 6.2 years (0.01 to 14.6 years) including one malpositioned cup in a female patient with developmental dysplasia who dislocated post-operatively and had to be repositioned. 9 hips failed from collapse of the femoral-head and 3 hips from femoral-neck fractures, giving rise to 12 femoral failures in all. There were six deep infections and three bearing-related failures including one pseudotumour, one for osteolysis and one for unexplained pain with neither metallosis nor pseudotumour.
With revision for any reason as the end-point Kaplan-Meier survival analysis showed 98.9%, 98.6% and 97.2% implant survival at 5, 10 and 17 years. Men had better survival (99.1% and 98.1% at 10 and 17 years respectively) than women (97.3% and 95.3%).
17-year cumulative revision rates were higher in patients with a pre-operative diagnosis of dysplasia (6.1%) and AVN (7.6%) compared to all other diagnoses combined (1.5%). Patients with osteoarthritis had the best results (99.5%, 99.3%, 98.4% at 5, 10 and 17 years respectively).
Our study shows that resurfacing arthroplasty is a viable option for hip arthritis in the young with a low incidence of wear-related failures in the long-term.