Summary

This study compares clinical outcome scores of multiligament knee reconstructions between smokers and nonsmokers, and assesses any differences in complications, revision rate, or other objective outcomes.

Abstract

Background

Smoking has a well-established relationship with cardiopulmonary disease, and is a major preventable cause of morbidity and mortality. Limited wound healing, postoperative infection, and insufficient bone graft healing are all documented complications associated with nicotine use. Recent ACL reconstruction literature has demonstrated deteriorated subjective and objective clinical outcomes in smokers, as well as poorer outcomes with allograft use. Smoking also displays a dose-dependent relationship with increasing postoperative knee laxity.
Relative to isolated ACL injuries, multiligament knee injuries (MLKI) represent a greater level of complexity, and greater opportunity for smoking to negatively affect outcomes. These injuries are often associated with a higher degree of soft tissue damage, vascular compromise, open procedures, and allograft use. Many of these injury patterns are best managed acutely, which does not allow much time for preoperative smoking cessation. This study compares clinical outcome scores of multiligament knee reconstructions between smokers and nonsmokers, and assesses any differences in complications, revision rate, or other objective outcomes.

Methods

A retrospective chart review was performed for radiographic knee dislocation patients with one two or more ligaments with grade 3 instability requiring repair or reconstruction. Eligible ligaments included the ACL, PCL, MCL, LCL, or popliteus. Additional inclusion criteria consisted of documented nicotine use and >1 year of follow up with clinical outcome scores. Outcome scores (Lysholm, IKDC, & SMFA) between smokers and nonsmokers were compared to assess differences in complication rates and objective measurements.

Results

A total of 118 patients were included; 73 nonsmokers and 45 smokers (minimum one daily pack cigarettes/chew). Mean time to treatment was 22 days. At last follow-up (mean 22 months), 50% of smokers had a range of knee motion classified as normal (0-135° ± 10°). Mean Lysholm score for smokers was 61.1, with 67.2 for nonsmokers. Mean IKCD score for smokers was 47.6, compared to 55.3 for nonsmokers. Smokers also had higher incidences of postoperative superficial infection and pulmonary embolism.

Conclusions

Nicotine use is associated with worse clinical outcomes and more complications with MLKI. This could lead to a prognosis change for smokers, further emphasizing their need to quit, and potentially lead to timing modifications for certain injury treatments and graft choices. To our knowledge this is the first study of its kind, pivotal to further understanding factors that lead to poor outcomes in multiligament knee reconstructions and how to prevent them.