Biomechanical differences between cases with chronic exertional compartment syndrome and asymptomatic controls during walking and marching gait.

Chronic exertional compartment syndrome is a significant problem in military populations that may be caused by specific military activities. This study aimed to investigate the kinematic and kinetic differences in military cases with chronic exertional compartment syndrome and asymptomatic controls. 20 males with symptoms of chronic exertional compartment syndrome of the anterior compartment and 20 asymptomatic controls were studied. Three-dimensional lower limb kinematics and kinetics were compared during walking and marching. Cases were significantly shorter in stature and took a relatively longer stride in relation to leg length than controls. All kinematic differences identified were at the ankle. Cases demonstrated increased ankle plantarflexion from mid-stance to toe-off. Cases also demonstrated less ankle inversion at the end of stance and early swing phases. Lower ankle inversion moments were observed during mid-stance. The anthropometric and biomechanical differences demonstrated provide a plausible mechanism for the development of chronic exertional compartment syndrome in this population. The shorter stature in combination with the relatively longer stride length observed in cases may result in an increased demand on the anterior compartment musculature during ambulation. The results of this study, together with clinical insights and the literature suggest that the suppression of the walk-to-run stimulus during group marches may play a significant role in the development of chronic exertional compartment syndrome within a military population. The differences in joint angles and moments also suggest an impairment of the muscular control of ankle joint function, such as a reduced effectiveness of tibialis anterior. It is unclear whether this is a cause or consequence of chronic exertional compartment syndrome.