Summary

Investigating the effect of laterality on patient outcomes following multiligamentous knee injuries using functional knee assessments and subjective patient reported outcomes.

Abstract

Introduction

A multiligament knee injury (MLKI) is defined as a tear of at least two of the four major knee ligament structures: the ACL, PCL, MCL, and the Posterolateral Corner (PLC) which includes the LCL. While MLKIs account for as little as 0.2% of orthopaedic injuries, these injuries are complex and traditionally have poor long-term health outcomes, and there is little consensus literature on the management of this pathology. Many studies have looked at the effect of operative vs. nonoperative treatment, early vs. delayed reconstruction, and return to work or sports following MLKIs, but to date there is no published literature on the effect of laterality on multiligament knee injuries. It stands to reason that variable injury patterns have varying prognoses, but no research has been done to validate this.

Specific Aims: This retrospective chart review assessed outcomes in patients with MLKIs over a 5-year period. MLKI patients were subdivided into those with medial sided injuries (MLKIs including the MCL or PLC) versus those with lateral sided injuries (PLC without the MCL) to see if there was a statistically significant difference between the 2 cohorts.

Study Methods: A retrospective chart review was performed to identify 27 patients, at least 6 months recovered from a MLKI. The patients were treated by 3 fellowship-trained orthopaedic sports surgeons at the Medical College of Wisconsin. These patients were stratified into medial and lateral cohorts. Objective data was obtained from patient records including maximum extension, maximum flexion, and laxity grades at the time of their last or most recent visit. Patient satisfaction was quantified using standardized phone surveys modeled after the International Knee Documentation Committee Form (IKDC).

Results

Of the 27 patients that met our inclusion criteria, 21 had lateral sided MLKI’s and 6 had medial sided MLKI’s. There was no significant difference in maximum extension (p=.88) or flexion (p=.266) between cohorts. The lateral cohort trended towards increased laxity grades (mean medial = 0.88, mean lateral = 0.62), however, the difference was not statistically significant (p=.601). There was a significant difference in IKDC form scores between cohorts (p=.017), with the lateral sided cohort reporting worse outcomes (mean medial = 84.29, mean lateral = 64.86).

Conclusions

The lateral sided cohort had significantly worse patient reported outcomes than the medial sided cohort, with a trend towards an increase in laxity. This makes sense as the anatomy of lateral-sided knee structures is far more complex, and lateral sided knee injuries are more likely to be accompanied by neurovascular complications. It stands to reason that an injury to this side would have a worse outcome. Knowing that patients with lateral-sided knee injuries do subjectively worse than their medial sided counterparts, the next step in this research would be to implement a randomized control study assessing more aggressive therapy and/or surgical management protocols, with the understanding that current treatment algorithms result in lateral-sided patients doing subjectively worse. At minimum, this data highlights the importance of managing patients’ expectations when faced with a new diagnosis for one of these devastating injuries.