OBJECTIVE: Control of gait after limb-saving surgery.Design. Case series study. BACKGROUND: At the moment little is known about adaptations in patients' gait after limb-saving surgery. METHODS: Nineteen patients who underwent limb-saving surgery at least 1 yr earlier and 10 normal subjects were studied during treadmill walking. The main outcome measures were walking speed, step parameters and angular displacement of both legs and EMG of the biceps femoris, rectus femoris and medial gastrocnemius in the affected leg. RESULTS: Preferred walking speed in the patients was lower than in the controls (0.7 versus 1.1 m/s). Furthermore, stance phase of the non-affected leg was lengthened. All patients showed reduced stance phase knee flexion in the affected leg, while during the swing phase no difference was seen. The EMG signals of the rectus femoris and biceps femoris show changes, which are related to the location of surgery. CONCLUSIONS: The results showed that the gait pattern of the patients differed compared to normal gait. The reduced stance phase knee flexion in the hip group is based on a high degree of co-contraction between quadriceps and hamstring activity, while in the knee group this is based on the quadriceps avoidance pattern. The finding that there is still side-to-side asymmetry indicates that there is no complete reorganisation following the massive loss of input and output of the leg. It is possible that some reprogramming of the locomotor process occur. RELEVANCE: Gait and electromyographic analysis are essential for the quantitative assessments of the functional outcome in this type of surgery.