As a result of the increased popularity of metal-on-metal bearings for total hip arthroplasty, concerns have been expressed about patient exposure to increased serum metal ion levels.

We therefore performed a retrospective review of patients with metal-on-metal, uncemented Ring total hip replacements with a minimum follow up of thirty years.

After allowing for prosthesis revision and patient mortality, 6 hips in 5 patients were reviewed and serum ion levels measured. Similar cohorts of patients with other combinations of bearings were compared with an age-matched osteoarthritic control group.

Serum cobalt and chromium levels in the metal-on-metal hip arthroplasty group were significantly higher than in all other groups and approximately five and three times greater respectively than in the group with no implants. Unlike the stainless steel-on-plastic group, the cobalt/chrome-on-plastic group showed significantly raised serum cobalt levels compared with the control group. It is of interest that patients who have had their metal-on-metal hip replacements revised to metal-on-plastic, have metal ion levels that are not statistically different to those of the osteoarthritic control group.

Though we acknowledge the small numbers of patients studied, no identifiable harmful effects were found.

We conclude that serum metal ions remain elevated throughout the life of the metal-on-metal articulation. Metal bearing hip arthroplasty is being used in ever younger patients and together with increased life expectancy we are exposing our patients to potentially harmful levels of metal ions throughout the life of the implant.

Metal-on-metal bearings for total hip replacement (THR) are becoming increasingly popular. Improved wear characteristics mean that these articulations are being inserted into younger patients in the form of THR and resurfacing procedures. This has led to concerns regarding potential carcinogenicity because of the increased exposure to metal ions that the procedure brings.

We have studied the serum cobalt and chromium concentrations in patients who had primary, well-fixed Ring metal-on-metal THRs for more than 30 years. The levels of cobalt and chromium were elevated by five and three times, respectively compared with those in our reference groups. Metal-on-metal articulations appear to be the source of metal ions throughout the life of the prosthesis. In three patients who had undergone revision of a previous metal-on-metal THR to a metal-on-polyethylene replacement the levels of metal ions were within the normal range. The elevations of cobalt and chromium ions seen in our study were comparable with those in patients with modern metal-on-metal THRs.

Introduction Rheumatoid arthritis commonly produces disabling forefoot deformities. Surgical interventions include hallux metatarsophalangeal (MTP) joint fusion with lesser toe metatarsal head and/or proximal phalanx base excisions. Here we describe our experience of combining first MTP joint fusion using a plate with Weil metatarsal osteotomies (WMO) of the lesser toes. WMO preserve and reduce lesser MTP joints thus enhancing stability and relocating the plantar fat pads. Plate fusion of the first MTP joint protects against recurrent deformity. Our aim was to assess the outcome of this procedure.

Method Twelve female patients (21 feet) underwent the procedure with no loss to follow up. Informed consent was given and ethics approval obtained. American Orthopaedic Foot and Ankle Society (AOFAS) forefoot scale and visual analogue scale scores were recorded post-operatively only. Pre- and post-operative plain radiographs were compared.

Results Mean age at operation was 62.5 years (range 48–75). Mean follow up was 25.9 months (range 2–54). The mean post-operative AOFAS scale score was 70.6/100 (range 34–90).

The mean hallux valgus angle was reduced from 39.6 degrees to 31.8 degrees and the second MTP angle from 28.3 degrees to 19.4 degrees. Pre-operatively 28% of the lesser toe MTP joints were aligned compared with 83% post-operatively. All of the WMOs fused. Two first MTP joint fusions resulted in non-unions and required successful revision surgery. In five cases metalwork was removed from the hallux because of discomfort. In two cases, metalwork was removed because of superficial wound infection. Infection subsequently resolved after a course of oral antibiotics. Nine patients stated they would recommend the procedure.

Conclusion First MTP joint plate arthrodesis and WMOs of the lesser toes provides good symptomatic relief and restoration of forefoot mechanics. It is a useful procedure in delaying more radical and final surgery for this progressive, destructive disease.