Factors Affecting Graft Remodeling and Anterior Cruciate Ligament Reconstruction: MRI Study of 180 Knees.

BACKGROUND: Several factors affect the retear rate after anterior cruciate ligament (ACL) reconstruction, but there are few data on which factors affect graft remodeling.

PURPOSE: To determine which factors are associated with the remodeling of an ACL graft.

STUDY DESIGN: Case-control study; Level of evidence, 3.

METHODS: A retrospective longitudinal study was conducted to investigate the relationship between various exposure factors and the occurrence of an "event": graft remodeling measured with the signal-to-noise quotient (SNQ). Data were collected prospectively and analyzed retrospectively for this study. The endpoint was the SNQ on magnetic resonance imaging at postoperative 1 year. The effect of the following parameters on SNQ was investigated: sex, smoking habits, age at surgery, body mass index, time to surgery, time to return to sports, type of sport (in-line, pivot, contact), type of graft (free semitendinosus [ST] or attached ST), and addition of lateral tenodesis.

RESULTS: An overall 180 patients were enrolled (90 with each technique). The following factors were significantly and independently associated with the SNQ: attached ST graft (β = -2.624668; P < .001), age at the time of surgery (β = -0.7948476; P = .012), and time elapsed between the injury event and surgery (β = -0.7137424; P = .046).

CONCLUSION: Leaving the ST graft attached distally, being older at the time of surgery, and having more time elapse between the injury event and ACL reconstruction surgery were significantly associated with better graft remodeling.