Four-year results from a randomized controlled study of knee chondroplasty with concomitant medial meniscectomy: mechanical debridement versus radiofrequency chondroplasty.

PURPOSE

This randomized study was undertaken to compare the effectiveness of simple mechanical debridement and 50 degrees C controlled bipolar chondroplasty.

METHODS

A total of 60 patients who had a grade III articular cartilage defect of the medial femoral condyle were included. After randomization, 30 patients underwent simple debridement of articular cartilage defects, which was performed with a mechanical shaver (mechanical shaver debridement [MSD] group). The remaining patients underwent thermal chondroplasty, which was performed with a temperature-controlled bipolar device with a constant thermo-application of a maximum of 50 degrees C (radiofrequency-based chondroplasty [RFC] group). All patients underwent partial (n = 41) or subtotal (n = 19) meniscectomy. Follow-up was undertaken 4 years postoperatively.

RESULTS

No significant differences between the preoperative findings for the 2 groups were observed. One patient from the MSD group had died, and one female patient in the RFC group was lost to follow-up. A total of 18 patients had undergone revision operations for persistent knee problems: in the MSD group, there were 8 endoprostheses, 4 osteotomies, and 2 revision arthroscopies, whereas in the RFC group, there was 1 replacement, 2 osteotomies, and 1 revision arthroscopy with subtotal medial meniscectomy. The proportion of revisions was significantly higher in the MSD group (P = .006). These patients were excluded from the evaluation. The remaining 40 patients from both groups benefited from the operation. The preoperative Knee Injury and Osteoarthritis Outcome Score (KOOS) was 11.3 points in the MSD group and 15.5 points in the RFC group (P = .279). Patients from the MSD group had a KOOS of 53.2 points at the time of follow-up. In the RFC group the KOOS (71.8 points) was significantly higher (P < .001).

CONCLUSIONS

Compared with classical mechanical debridement, bipolar radiofrequency currently appears to be the superior method for achieving a good midterm result.

LEVEL OF EVIDENCE

Level I, randomized controlled trial.