Patients with isolated posterior cruciate ligament deficiencies frequently do not have major symptoms of knee instability. However, if the posterior cruciate ligament dysruption is associated with other deficiences, severe, disabling instability is common. One of the most common types is posterolateral instability. Authors have used the biceps rerouting technique of Clancy for the posterolateral rotary instability of knees in 28 patients. Follow-up period ranged from 12 month to 2 year 6 months. Results of biceps rerouting technique were analysed clinically, Six out of 7 acute cases (85.7%) and 18 out of 21 chronic cases (85.7%) were rated as good on the objective evaluation. On functional evaluation using the Lysholm rating system of knee ligament injuries, 5 out of 7 acute cases (71.5%) and 15 out of 21 chronic cases (71.5%) were rated as good at the final follow-up.