LONG TERM OUTCOME OF FRESH OSTEOCHONDRAL GRAFTS FOR TIBIAL PLATEAU FRACTURES

Abstract

Objectives: Fresh osteochondral allografts are well-established treatment for patients who have posttraumatic osteochondral defects over 3cm in diameter and 1cm in depth of the knee. The objective of our study was to investigate the long-term outcome of these grafts and how long they may delay need for arthroplasty in patients with mal-united tibial plateau fractures.

Method: A prospective cohort study of patients who had received fresh osteochondral allografts of the tibial plateau was conducted. 118 patients were identified and survivor ship analysis was performed using conversion to total knee arthroplasty as the end point for graft failure. The Modified Hospital for Knee Surgery Scoring System (MHKSS) was used to clinically assess each patient who had more than five years of follow up. Radiographs were assessed for mechanical axis as well as using the Tonis grade for degenerative change.

Results: 29 of 118 (25%) experienced graft failure and underwent conversion to total knee arthroplasty, at a mean of 12 years (range 3–23) after the index procedure. The remaining 52 patients with a successful graft, and follow up over five years, had a mean MHKSS score of 83 (range 49–100) with a mean follow up of 11.7 years (range 5–34). Kaplan-Meier survivorship analysis of all 118 patients showed that graft survivorship was 94% at 5 years (std err 2.7), 83% at 10 years (std err 4.6), 62% at 15 years (std err 7.4) and 45% at 20 years (std err 8.5). Factors that predicted a successful graft were, using a meniscal allograft in conjunction with the osteochondral graft, and a lateral tibial plateau defect. The age at the time of surgery was no different between the patients that had a successful graft or those that failed.

Conclusion: Fresh osteochondral allografting works well in providing long term treatments for patients with tibial plateau damage. The concurrent use of meniscal allografts is also recommended.