To evaluate the complication rates after conversion of hip and knee fusions to total joint replacements in the Province of Ontario.
A retrospective cohort study.
Those who had undergone an elective conversion of a hip or knee fusion to a total joint replacement during fiscal year 1993 through 1996, as captured in the Canadian Institute for Health Information and Ontario Health Insurance Plan databases.
Inhospital complications and length of initial hospital stay, revision, infection, amputation and repeat fusion rates within 4 years.
Conversion of hip and knee fusion to total joint arthroplasty was generally performed by high-volume surgeons in high-volume hospital settings. Forty hip and 18 knee replacements involved conversion of a previous fusion. Conversion of a hip fusion was associated with a 10% infection rate, a 10% revision rate and a 5% resection arthroplasty rate due to infection within 4 years of the conversion. Conversion of a knee fusion was associated with an 11% infection rate, and a more than 5% revision rate at 4 years. Over 16% of patients who underwent conversion of a knee fusion required removal of the components (for various reasons) within the first 4 years.
There is a high rate of complications after conversion of a hip or knee fusion to a total joint arthroplasty. These issues must be carefully considered and discussed with the patient before any conversion procedure.