Dynamic Varus and the Development of Iliotibial Band Syndrome.

CONTEXT: Although the risk of osteoarthritis development after acute knee injury has been widely studied, the long-term consequences of knee overuse injury are not well understood. OBJECTIVE: To identify the relationship between gait-related risk factors associated with osteoarthritis and the development of iliotibial band syndrome (ITBS) in members of a single University Army Reserve Officers' Training Corps unit. DESIGN: Prospective cohort study. SETTING: Biomechanics laboratory. PATIENTS OR OTHER PARTICIPANTS: Sixty-eight cadets undergoing standardized physical fitness training. INTERVENTION(S): Three-dimensional lower extremity kinematics (240 Hz) and kinetics (960 Hz) were collected for 3 bilateral trials during shod running at 4.0 m/s ± 10%. Injury tracking was conducted for 7 months of training. MAIN OUTCOME MEASURE(S): Biomechanical variables, including varus thrust and knee-adduction moment, were compared between the injured and control groups. RESULTS: Twenty-six cadets with no history of overuse injury served as the control group, whereas 6 cadets (7 limbs) who developed ITBS that required them to modify their training program or seek medical care (or both) served as the injured group. Maximum varus velocity was higher ( P = .006) and occurred sooner during stance ( P = .04) in the injured group than in the control group, indicating greater varus thrust. Maximum knee-varus angle and maximum knee-adduction moment were higher ( P = .02 and P = .002, respectively) and vertical stiffness was lower ( P = .03) in the injured group. CONCLUSIONS: Measures of dynamic varus stability appeared to be altered in individuals who developed ITBS. Biomechanical knee variables previously identified as increasing the risk for knee osteoarthritis were also associated with the development of ITBS in healthy adults.

Long-term outcomes of a dynamic ankle-foot orthosis on gait characteristics of a service member with incomplete nerve injury to the lower extremity: a case report.

This case study reports a 5-year follow-up of a 32-year-old male service member who suffered polytrauma in 2007 following a Humvee rollover in Afghanistan. The service member's injured left lower extremity was salvaged, but severe damage to the lumbosacral plexus and significant injuries to the pelvis, hip, and femur resulted in near total paralysis and foot drop of the left lower limb. Two years of multiple substandard ankle-foot orthotic devices pushed him to investigate a dynamic ankle-foot orthotic (DAFO) with energy storing capability, which allowed him to remain on active duty and deploy for a second tour while wearing the device. The anecdotal improvements described by this service member prompted a biomechanical analysis of walking and running gait, comparing a shoes only condition to the DAFO. Results of gait analysis demonstrated an improvement in spatial-temporal parameters in both walking and running, improved sagittal angles and moments at the ankle, knee, and hip, greater ankle stability through decreased dorsiflexion excursion, and a marked increase in ankle power while running. Most notably, the service member credits this device for substantial improvement in quality of life including total cessation of pain medication and return to regular vigorous activity.