Smoking is associated with a higher chance of graft rupture after anterior cruciate ligament reconstruction

Abstract

Introduction: The incidence of anterior cruciate ligament reconstruction (ACLR) graft rupture was reported to be 7.9% at 10-year follow-up. It has been known that smoking clinically impacted on different orthopaedics surgery and tissue healing. Yet, there is limited study on the implication of smoking on graft rupture after ACLR. Methods: From 1 January 2013 to 31 December 2019, 233 patients who received primary ACLR with hamstring tendon autograft were assessed by MRI at a mean 20.2 ± 1.9 months after surgery. Based on their smoking history, the patients were categorised into two groups: smokers (n=39) and non-smokers (n=194). Primary outcome was ACLR graft rupture (diagnosed by either arthroscopy or magnetic resonance imaging). The secondary outcome was signal/noise quotient (SNQ), which assessed the signal intensity of the intact graft quantitatively. Results: The rate of ACLR graft rupture was 6.0%. Smokers had a higher rupture rate (12.8%) than non-smokers (4.6%) [p=0.0498, chi square test]. The odd ratio was 2.76. The intact graft of smokers was found to have a less satisfactory ligamentisation (p=0.028) because of higher SNQ (4.7 ± 4.4) than non-smokers (SNQ=3.3 ± 3.7) [p=0.028]. The two groups were comparable in other parameters, including demographics, length of follow-up, and surgical details. Discussion and Conclusion: In reference to the postoperative MRI captured at an average of 20 months after index surgery, smoking posed a higher the risk of graft rupture of ACLR and undermined the ligamentisation process of the intact graft.