COMPLICATIONS AND RE-OPERATIONS FOLLOWING PRIMARY TOTAL KNEE REPLACEMENT FROM THE TRENT ARTHROPLASTY JOINT REGISTER

Abstract

We sought to determine the incidence of complications and re-operation up to one year following primary total knee replacement in a single health region.

The Trent Arthroplasty Audit group collects prospective data on all knee replacements performed within this health region (population 5.2 million). All patients are sent a validated, self-administered questionnaire one year after surgery. The questionnaire addresses patient satisfaction and any complications and re-operations following surgery. We analysed the returned questionnaires of 5352 patients [5896 knees] who had their primary knee arthroplasty between 1998 to 2000. Responses were received from 4169 patients [4592 knees] (response rate 80%). Clinical records were also examined to gain further information.

516 patients reported complications in 546 knees. Complication rate of (12%) and 3.5% had a further operation on the joint within one year. Complications were highest following knee replacement for trauma (36%) followed by osteoarthritis (12%) and lowest for rheumatoid arthritis (8%). We have no knowledge of the complexity of the surgery but 60% of the complications occurred in patients operated on by a Consultant, 29% by a Specialist Registrar and 10% by an Associate Specialist & Staff Grade. On the whole Consultants performing fewer than 10 joint replacements per year registered a higher complication rate (21%) as compared to Consultants performing more than 25 joints per year (12%), but they performed 18% of the arthroplasties. The incidence of complications, as stated by the patient was as follows: Pain 7%, Stiffness 2%, Superficial infection 1%, Swelling 0.7%, Deep infection 0.7%, DVT 0.4%. 1.2% (infection 0.4%: Instability 0.7%: Patellar resurfacing 0.2%), Manipulation (1.3%), Arthroscopy (0.7%), ORlF of Peri-prosthetic fracture (0.06%). 12 % of the patients who had a primary knee replacement in Trent region between 1998 and 2000 considered that they had a complication. Complications rates appear to be higher for surgeons performing less than 10 joint replacements per year. Only 43% of Consultants performed more than 10 knee arthroplasties themselves in any one of these three years. The deep infection rate was 0.4% and one-year post surgery the revision rate, for all causes was 1.2% and the manipulation rate was 1.3%.