The influence of muscle strength on the gait profile score (GPS) across different patients

- The effect of muscle strength on the gait profile score (GPS) was evaluated.
- Muscle strength had the same negative effect on GPS across different patient groups.
- The severity of the pathology is reflected in a GPS-offset at normal muscle strength.
- Spasticity had less impact on gait kinematics than expected.

BackgroundMuscle strength greatly influences gait kinematics. The question was whether this association is similar in different diseases.MethodsData from instrumented gait analysis of 716 patients were retrospectively assessed. The effect of muscle strength on gait deviations, namely the gait profile score (GPS) was evaluated by means of generalised least square models. This was executed for seven different patient groups. The groups were formed according to the type of disease: orthopaedic/neurologic, uni-/bilateral affection, and flaccid/spastic muscles.ResultsMuscle strength had a negative effect on GPS values, which did not significantly differ amongst the different patient groups. However, an offset of the GPS regression line was found, which was mostly dependent on the basic disease. Surprisingly, spastic patients, who have reduced strength and additionally spasticity in clinical examination, and flaccid neurologic patients showed the same offset. Patients with additional lack of trunk control (Tetraplegia) showed the largest offset.ConclusionGait kinematics grossly depend on muscle strength. This was seen in patients with very different pathologies. Nevertheless, optimal correction of biomechanics and muscle strength may still not lead to a normal gait, especially in that of neurologic patients. The basic disease itself has an additional effect on gait deviations expressed as a GPS-offset of the linear regression line.