Ten-year survivorship after knee arthroscopy in patients with Kellgren-Lawrence grade 3 and grade 4 osteoarthritis of the knee

Abstract

Purpose: The purpose of this study was to document 10-year outcomes and total knee arthroplasty (TKA) rate after arthroscopic treatment of knee osteoarthritis and compare survivorship of patients with Kellgren-Lawrence (KL) grade 3 and 4 knees.

Methods: Eighty-one knees in 73 patients (49 male, 32 female; mean age, 58 years; range, 37 to 79 years) that underwent an arthroscopic regimen for knee osteoarthritis between August 2000 and November 2001 were included in this institutional review board-approved study. The inclusion criterion was Kellgren-Lawrence (KL) grade 3 or 4 radiographic changes. A TKA had been recommended to all patients; however, none wished to undergo arthroplasty. All patients underwent arthroscopic treatment. Endpoint was defined as TKA for survivorship analysis. Outcomes were collected at a minimum follow-up of 10 years (Lysholm, Tegner, patient satisfaction, and WOMAC scores).

Results: Of 81 knees, 7 were in patients who died and 2 in patients who refused to participate, leaving 72 knees available for follow-up. Follow-up was obtained for 95% of patients (n = 69). Forty-three knees (62%) were converted to TKA at a mean of 4.4 years (range 1.0 to 9.6) after index arthroscopy. Mean survival time was 6.8 years (95% confidence interval [CI], 5.9 to 7.6 years). Survivorship was 60% at 5 years and 40% at 10 years. Patients with KL grade 4 osteoarthritis were 5.3 times more likely to fail (95% CI, 1.3 to 23.4) than those with KL grade 3 (P = .012). Mean survival time for patients with KL grade 4 was 5.7 years (95% CI, 4.5 to 6.9), and mean survival time for those with KL grade 3 was 7.5 years (95% CI, 6.2 to 8.7) (P = .022). For 26 knees that did not undergo arthroplasty, the mean Lysholm score was 74 (95% CI, 67 to 80), the median Tegner activity scale score was 3 (range, 0 to 8), the median patient satisfaction with outcome was 9 (range, 1 to 10), and the mean WOMAC score was 18.5 (95% CI, 13 to 24) at 10 years of follow-up.

Conclusions: The mean survival time after arthroscopic treatment of osteoarthritis with a defined protocol was 6.8 years. Forty percent delayed arthroplasty for a minimum of 10 years. Patients with KL grade 4 changes in their knee had a higher risk of conversion to arthroplasty and a significantly lower mean survival time.

Level of evidence: Level III, retrospective comparative study.