Chondral resurfacing and high tibial osteotomy in the varus knee: survivorship analysis.

BACKGROUND

Active patients with arthritic malalignment of the knee are difficult to manage. Arthroplasty, unicompartmental or total knee replacement, may not be appropriate in patients who desire to remain highly active. High tibial osteotomy has been recommended for the treatment of varus osteoarthritis to decrease pressure on the damaged medial compartment.

PURPOSE

To determine the length of time patients with varus gonarthrosis can avoid knee arthroplasty with chondral resurfacing (microfracture) and medial opening wedge high tibial osteotomy (HTO).

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

From 1995 to 2001, the senior authors performed a medial opening wedge HTO/microfracture in 106 knees (mean age, 52 years; range, 30-71 years). Survivorship was defined as not requiring knee arthroplasty after microfracture and HTO.

RESULTS

At 5 years, survivorship was 97%. At 7 years, survivorship was 91%. Twelve patients proceeded to arthroplasty at a mean of 81 months (range, 19-116 months). Follow-up was obtained for 90% of patients. At most recent follow-up, the mean Lysholm score was 71 (range, 5-100). At 3 years, the mean Lysholm score was 73, Tegner score was 2.8, and patient satisfaction was 7.9. At 5 years, the mean Lysholm score was 73, Tegner score was 3.8, and patient satisfaction was 7.5. At 9 years, the mean Lysholm score was 67, Tegner score was 3.1, and patient satisfaction was 7.5. Patients with medial meniscus injury at surgery were 9.2 times more likely to undergo arthroplasty than patients without (95% confidence interval [CI], 1.4-13.5; P = .015).

CONCLUSION

With 91% survivorship at 7 years, microfracture/HTO seems to contribute to a delay of knee replacement in active patients with varus gonarthrosis. Patients who proceeded to knee arthroplasty after combined HTO/microfracture had a mean delay of 81.3 months.