Plantarflexion/dorsiflexion strength and isokinetic range of motion following injury to the ankle lateral collateral ligament

Isokinetic range of motion (ISORoM) and peak torque (PT) at the ankle joint were examined in 37 patients, in two different knee positions (extended and flexed at 90degrees), six months following Lateral Collateral Ligament (LCL) trauma: 2nd and 3rd degree sprains had been sustained by 18 and 19 patients respectively. Patients were immobilized for six weeks in a plaster-of-Paris cast, with 3rd degree sprains undergoing surgical repair prior to immobilization: all patients followed the same physical therapy regime designed to regain full range of motion by mobilizing the joint, strengthen the muscles and improve proprioception. Significant differences (p < 0.01) in ISORoM were observed between the injured and noninjured ankle for each group, with those with 3rd degree sprains also showing a significant reduction (p < 0.01) in ISORoM compared with 2nd degree sprains. No differences were found in PT generation during concentric and eccentric contractions for both muscle groups. Measurement of the ISORoM and muscular strength, following LCL trauma, appears to be a useful tool in clinical evaluation and treatment planning.