2015 ISAKOS Biennial Congress ePoster #1123

Return to Duty Rate After Combat-Related Multiligamentous Knee Injury

Aaron Barrow, MD, San Antonio, TX UNITED STATES
Andrew Sheean, MD, San Antonio, TX UNITED STATES
Travis Burns, MD, San Antonio, TX UNITED STATES

San Antonio Military Medical Center, San Antonio, Texas, USA

FDA Status Not Applicable

Summary: Retrospective study of combat-related multiligamentous knee injuries among an active-duty population that characterizes ligament injury patterns, associated injuries, current treatment practices, and evaluates the injury and treatment characteristics as predictors of patient outcomes.




The purpose of this study was to characterize injury patterns, treatment outcomes, and the return to duty (RTD) rate of active duty soldiers who sustained multiligamentous knee injuries (MLKI) while deployed during in a combat setting.


We retrospectively reviewed the medical records of 46 soldiers who had sustained 48 MLKIs between 2003 and 2011. Injuries were characterized based upon mechanism (high vs. low energy), ligament injury pattern, number of ligaments injured, the presence of associated arterial and vascular injuries, ipsilateral fractures, traumatic arthrotomy, and co-morbid injuries. Methods of injury treatment (acute external fixator placement vs splint; operative vs non-operative; early definitive surgery vs. delayed surgery, single-stage vs. two-stage surgery) were also identified. We then compared treatment outcomes including: pain, range of motion (ROM), instability, operative complications, need for revision surgery, need for manipulation under anesthesia, and RTD rate.


Forty (83%) of the MLKIs were the result of high-energy, combat-related events. The most common injury pattern (19%) was combined disruption of the anterior cruciate ligament, posterior cruciate ligament, posterolateral corner, and medial collateral ligament. Twenty one knees (44%) had an ipsilateral tibia fracture, 11 (23%) had an ipsilateral femur fracture, 12 (25%) had ipsilateral ankle/foot fractures, and 11 (23%) sustained a traumatic arthrotomy. There were 11 (18%) associated vascular injuries, 16 (33%) nerve injuries, and 11 extremities (18%) developed compartment syndrome. Acute treatment with an external fixator was a significant risk factor for decreased ROM (p=0.001) and post-operative infection (p=0.031). The most common method of definitive ligament treatment was delayed single-stage operative reconstruction (48%). Early ligament reconstruction (<3 weeks from injury) was a risk factor for needing MUA (p=0.039). The overall RTD rate was 41%. High energy injury, nerve injury, vascular injury, compartment syndrome, traumatic arthrotomy, presence of ipsilateral extremity ankle/foot fracture, and poor ROM were all significant factors in preventing RTD (p<0.05). Both specific ligament injury pattern and number of ligaments injured were not significant predictors of any measured patient outcome.


MLKIs sustained in combat have a higher incidence of ipsilateral extremity fracture, neurovascular injury, traumatic knee arthrotomy, and compartment syndrome than has been previously reported on MLIs in civilian settings. These associated ipsilateral extremity injuries are the most important factors in predicting patient outcomes, including RTD rate. Active duty personnel that sustain non-combat related MLI are much more likely to be retained in the military.