Abstract
Aim
To assess the effectiveness of role of frozen section in revision arthroplasty.
Method
21 patients with infected hip arthroplasties were operated in the form of one or two-staged revision hip arthroplasties. A frozen section was obtained intra-operatively and >5 PMN's/ HPF was considered as a positive indicator of infection. Fig 1 llustrating frozen section image. If the frozen section was reported negative (≤5 PMN's/HPF), the revision prosthesis was implanted after a thorough debridement and a wash. If the frozen section was reported as positive, after the debridement a non-articulating antibiotic loaded cement spacer was implanted for 8 weeks, supplemented with 3 weeks of intravenous antibiotics and 3 weeks of oral antibiotics. This was followed by an antibiotic free interval of 2 weeks. The patient was taken up for a revision surgery once the frozen section study was negative (≤5 PMN's/HPF). The patients were followed up for minimum of 1 year to a maximum of 2 years after the revision for any evidence of infection (assessed clinically and serologically, radiologically).
Results
15 patients had a positive frozen section (>5PMN's/HPF) in the first stage and were treated with prosthesis removal and cement spacer insertion for 8 weeks. In the 2nd stage, out of 15 patients, 14 underwent revision arthroplasty, while 1 patient underwent reapplication of the cement spacer. As per the follow up of ESR & CRP values, clinically and radiologically no patients had any evidence of infection. The average follow up was 17.04 months (range 12–24 months). 1 patient had persistently raised ESR (34mm/hr) which may be attributable to other causes Frozen section analysis of PMN's per high power field had 100% specificity in our patients in detecting periprosthetic joint infection.
Conclusions
Intraoperative frozen section study is a reliable indicator in predicting a diagnosis of PJI with good accuracy in ruling out this diagnosis. Frozen section study should thus be considered a relevant part of the challenging diagnostic work-up for patients undergoing revision hip arthroplasty.
