Elevated blood metal ions are associated with the early failure of the Hip Resurfacing Arthroplasty. The aim of this study was to analyse our prospective database of Hip Resurfacing Arthroplasty patients, to independently review the outliers with elevated blood metal ions and to determine whether a screening program would be of value at our institution. In 2004 a ten year prospective longitudinal study was set up to evaluate the clinical effectiveness and safety of Metal on Metal Hip Resurfacings in young, active adults with degenerative hip disease. Six hundred and four patients have enrolled in this multi-surgeon prospective study with strict inclusion criteria for Hip Resurfacing Arthroplasty. All have received the same implant design. All have completed validated functional outcome questionnaires at baseline, three and six months, then annually. A sub-cohort of 196 patients underwent whole blood chromium and cobalt analysis at the same time periods. Metal on metal bearings have a running in period of a minimum of six months before a steady state wear pattern is attained. We chose five parts per billion for Cobalt or Chromium as our threshold value. This value corresponds to the workplace exposure limit in the United Kingdom to Cobalt in whole blood. Therefore patients with ion levels greater than five parts per billion after six months were recalled for independent review, including further metal ion analysis.Purpose
Method
We report a consecutive series of 200 patients who underwent Dynesys flexible stabilisation in the management of intractable lower back pain.
Group 1 - Cases where implantation was used as an adjunct to other procedures including decompression, discectomy, or posterior lumbar interbody fusion. (32 male, 36 female, Mean age 56years (range 31–85)). Group 2 - Patients with back pain and/or sciatica in which no other procedure was used. (65 male 67 female, Mean age 58years (range 27–86)) All patients were profiled prospectively using the Oswestry Disability Index (ODI), SF36 and Visual Analogue Scale (VAS). Patients were reviewed post-operatively using the same measures at 3, 6 &
12 months, and yearly thereafter. Follow-up was 95% at 2 to 5 years.
Group 2 – Mean ODI fell from 49 pre-op to 28 at four years Similar trends were observed in both groups with a fall in VAS and improvement in SF36.
We report the clinical and radiographic outcome of a consecutive series of 138 hydroxyapatite-coated total knee replacements with a mean follow-up of 11 years (10 to 13). The patients were entered into a prospective study and all living patients (76 knees) were evaluated. The Hospital for Special Surgery knee score was obtained for comparison with the pre-operative situation. No patient was lost to follow-up. Radiographic assessment revealed no loosening. Seven prostheses have been revised, giving a cumulative survival rate of 93% at 13 years. We believe this to be the longest follow-up report available for an hydroxyapatite-coated knee replacement and the first for this design of Insall-Burstein II knee.
