The influence of intraoperative pretensioning on the chondroprotective effect of meniscal transplants

Abstract

Background: Meniscal replacement has become more common in recent years. The meniscal transplant's ability to transfer load effectively depends on its ability to bear circumferential loading.

Hypothesis: Intraoperative pretensioning on the meniscal transplant sutures has a positive influence on meniscal transplants' chondroprotective effect.

Study design: Controlled laboratory study.

Methods: Thirty-six sheep were divided into 6 groups (n = 6), subjected to a sham operation (group A), a meniscectomy (group B), or a meniscal autograft using tag sutures with different levels of pretensioning (group C, 0 N; group D, 20 N; group E, 40 N; group F, 60 N). Macroscopic (International Cartilage Repair Society score) and histologic evaluations (Mankin score) of the articular cartilage were performed after 6 months.

Results: Higher suture pretension (40 N, 60 N) resulted in less cartilage degeneration than in meniscectomized (P =.047; P =.036) and nonpretensioned (P =.028; P =.015) knees, with International Cartilage Repair Society scores of 1.63 +/- 0.57 and 1.66 +/- 0.51 in groups E and F, respectively, and scores of 2.40 +/- 0.27 and 2.68 +/- 0.46 observed after meniscectomy and meniscal transplantation with no pretensioning, respectively. Group F had a significantly better Mankin score of 6.66 +/- 2.15 (P =.05) compared with group D. Regarding criterion cells, trends toward less degeneration compared with meniscectomized and nonpretensioned knees (P = .054 and P =.055) were found. The coefficient of variation of the Mankin scores was greater than that of the International Cartilage Repair Society score. Group A had significantly better cartilage than all other groups.

Conclusion: Adequate intraoperative pretensioning has a significant influence on the chondroprotective effect of meniscal transplants but did not prevent the development of articular cartilage degeneration.

Clinical relevance: The results suggest that intraoperative pretensioning could improve the chondroprotective effect of meniscal transplantation.