Multicenter Orthopaedics Outcomes Network Group

The Multicenter Orthopaedics Outcomes Network (MOON) has been instrumental in the evaluation and research of these patients for the past 10 years. This group has prospectively evaluated over 3500 ACL reconstruction patients from seven institutions to determine the prognosis and predictors of ACL reconstruction outcomes. Early work helped establish patient-reported outcomes as an appropriate method for assessing patient outcome as opposed to functional testing. The data collected have helped establish patient-specific statistical models to help clarify modifiable and nonmodifiable predictors related to injury, intraoperative decision making and treatment, postoperative rehabilitation protocols, and behavioral characteristics that contribute to a spectrum of clinically relevant outcomes. Additionally, when compared with rehabilitation, ACL reconstruction has been found to be cost-effective in both the short and long term. The group has concluded that limiting ACL reconstruction could potentially be harmful to not only the patient, due to the risk of the development of osteoarthritis, but also society, as ACL reconstruction showed improved quality-adjusted life years at a lower cost compared with rehabilitation.

This higher-level evidence now assists surgeons in preoperative discussions with patients to give insight about their prognosis, treatment options, and lifestyle choices that affect the knee. These data have also been practice-changing in that the use of allografts in young athletes is now avoided for their ligament reconstructions. Preoperative patient demographics have been evaluated to give insight to patient outcomes, particularly obesity and body weight, with the goal to improve ACL reconstruction outcomes by altering these modifiable predictors of worse outcomes.

Obesity and Anterior Cruciate Ligament Reconstruction

It has been estimated that 35.1% of adults in the United States are obese (body mass index [BMI] >30 kg/m ² ). This condition has been associated with musculoskeletal issues in the majority of research on osteoarthritis. In the orthopaedic sports medicine world, there has been a high prevalence of obesity associated with knee articular cartilage and meniscal injuries (26%–76%) and ACL injuries (33%–47%).

In joint reconstruction, obese patients have been found to have worse outcomes and more complications after total joint surgery than nonobese patients. These complications include reduced functioning and decreased range of motion, as well as increased risk for venous thromboembolism and periprosthetic joint infections. However, fewer studies have looked at the relationship of obesity in ACL reconstruction.

Four studies in the literature have found a negative association between BMI/obesity and ACL reconstruction patient-reported outcome measures. Heijne et al. reported that BMI was a significant predictor of Knee Injury and Osteoarthritis Outcome Score (KOOS) quality of life scores. Kowalchuk and colleagues discovered that lower International Knee Documentation Committee (IKDC) scores after ACL reconstruction were associated with obesity. From the MOON group, Dunn et al. showed that higher Marx activity levels existed for patients with lower BMI 2 years after surgery. Additionally, higher BMI was associated with more postoperative pain and symptoms on the KOOS. Cox et al. demonstrated that these relationships between obesity and activity continued at 6 years after ACL reconstruction in the MOON cohort. In a retrospective case series, a BMI of 28 kg/m ² or greater was correlated with fair to poor Lysholm and IKDC scores. While the studies presented so far found an association between obesity and poorer outcome measures, Ballal et al. displayed that there was no difference between high (BMI >25 kg/m ² ) and normal (BMI <25 kg/m2) BMI with postoperative Lysholm and KOOS scores in a retrospective comparative study.

Three studies have examined postoperative complications after ACL reconstruction, but none found any association with obesity. From the MOON group, Hettrich et al. did not find that obesity was a significant predictor for subsequent surgery on either knee. Additionally, Park et al. found no difference in failure rates at 2 years after reconstruction in patients with high (>25 kg/m ² ) and normal BMI. There was also no difference in complications between patients with high (>25 kg/m ² ) and normal BMI.

Obesity and Anterior Cruciate Ligament Reconstruction

It has been estimated that 35.1% of adults in the United States are obese (body mass index [BMI] >30 kg/m ² ). This condition has been associated with musculoskeletal issues in the majority of research on osteoarthritis. In the orthopaedic sports medicine world, there has been a high prevalence of obesity associated with knee articular cartilage and meniscal injuries (26%–76%) and ACL injuries (33%–47%).

In joint reconstruction, obese patients have been found to have worse outcomes and more complications after total joint surgery than nonobese patients. These complications include reduced functioning and decreased range of motion, as well as increased risk for venous thromboembolism and periprosthetic joint infections. However, fewer studies have looked at the relationship of obesity in ACL reconstruction.

Four studies in the literature have found a negative association between BMI/obesity and ACL reconstruction patient-reported outcome measures. Heijne et al. reported that BMI was a significant predictor of Knee Injury and Osteoarthritis Outcome Score (KOOS) quality of life scores. Kowalchuk and colleagues discovered that lower International Knee Documentation Committee (IKDC) scores after ACL reconstruction were associated with obesity. From the MOON group, Dunn et al. showed that higher Marx activity levels existed for patients with lower BMI 2 years after surgery. Additionally, higher BMI was associated with more postoperative pain and symptoms on the KOOS. Cox et al. demonstrated that these relationships between obesity and activity continued at 6 years after ACL reconstruction in the MOON cohort. In a retrospective case series, a BMI of 28 kg/m ² or greater was correlated with fair to poor Lysholm and IKDC scores. While the studies presented so far found an association between obesity and poorer outcome measures, Ballal et al. displayed that there was no difference between high (BMI >25 kg/m ² ) and normal (BMI <25 kg/m2) BMI with postoperative Lysholm and KOOS scores in a retrospective comparative study.

Three studies have examined postoperative complications after ACL reconstruction, but none found any association with obesity. From the MOON group, Hettrich et al. did not find that obesity was a significant predictor for subsequent surgery on either knee. Additionally, Park et al. found no difference in failure rates at 2 years after reconstruction in patients with high (>25 kg/m ² ) and normal BMI. There was also no difference in complications between patients with high (>25 kg/m ² ) and normal BMI.