Periprosthetic joint infection is a significant complication of total hip arthroplasty. The PRSThesis of Antibiotic Loaded Acrylic Cement (PROSTALAC) system can improve health related quality of life during a two step treatment approach for infection resolution. We investigated quality of life with the PROSTALAC in situ and also compared subjects who underwent second stage surgery with those who retained the PROSTALAC on a long term basis.

Twenty nine subjects were enrolled pre-PROSTALAC insertion, recording demographics, physical demand level and comorbidities. Subjects were then followed out to 24 months with either the PROSTALAC in situ or post revision for those who underwent the second stage surgery. Quality of life was evaluated using the Western Ontario McMaster Osteoarthritis Index (WOMAC) and RAND 36-Item Health Survey (RAND-36). Infection resolution was also determined for all subjects enrolled.

Three subjects died and 22/26 (84%) completed the evaluation. Overall 26 (85%) infections resolved. Following PROSTALAC insertion, WOMAC pain and function scores improved within three to six months and did not change out to 24 months. Physical function, bodily pain and vitality also significantly improved within three to six months postoperatively. Only seven (32%) subjects underwent second stage surgery. These individuals were more likely to be high demand (p=0.03) and trended towards being younger, male, with fewer comorbidities and lower BMI (p<0.10). There was no difference in WOMAC scores at 24 months between those who underwent second stage revisions and those who retained the PROSTALAC.

The use of a PROSTALAC implant improves health related quality of life. Long term retention of the PROSTALAC implant may be appropriate for low demand patients and considered for potentially high risk surgical candidates.

Purpose

The purpose of the study was to determine the rate of conversion from RSA to THR in a number of Canadian centers performing resurfacings

Purpose: Despite the excellent results of total knee arthroplasty (TKA), controversy over whether or not to resurface the patella persists. Anterior knee pain, which occurs with variable frequency, continues to be a problem in a subset of the TKA patient population. Some clinicians advocate resurfacing all patellae while others cite the complications attributed to patellar resurfacing as reasons to avoid this aspect of the procedure. Still others favour selective resurfacing based on subjective criteria. To address this clinical controversy, we prospectively randomized patients receiving TKA into two groups, those receiving patellar resurfacing and those left without resurfacing to determine clinical outcomes and revisions at five and 10 years postoperatively. Our primary objective was to compare the revision rate following TKA between the two study groups. Secondarily, we compared pain and function at five and 10 years and knee range of motion (ROM) over the first year.

Method: Patients receiving TKA were prospectively enrolled in the study and randomized intraoperatively to either receive patellar resurfacing or have no patellar intervention. All surgeries were performed through the standard medial parapatellar approach. The Smith and Nephew Profix TKA system was implanted in all cases and all subjects followed a standardized post-operative regimen. Subjects were assessed pre-operatively and at 6 months, 1, 3, 5 and 10 years postoperatively for knee ROM, function, and pain using the WOMAC and SF-36 questionnaires. Re-operations and revisions were also documented.

Results: Thirty-nine patients were enrolled in the study. There was 83% patient retention at five years and 74% at 10 years. Study groups were similar in baseline characteristics. At five years, three (18%) revisions had been performed in the retained patella group and one (5%) in the resurfaced group (p=0.31). There were no further revisions between five and 10 years. ROM was similar between the groups at all evaluations (p> 0.05). SF-36 and WOMAC scores demonstrated that both groups improved their pain and function significantly following surgery (p< 0.04).

Conclusion: The decision whether or not to resurface the patella during TKA remains controversial. This study demonstrated that initial results with either technique are comparable, but it appears that there may be clinically significant differences by five years postoperatively. These trends continued throughout the study and were statistically significant at the 10 year mark. Revision surgery was required in 18% of the retained group compared to 5% in the re-surfaced group.