Short communication

O 042 – Similarity of knee motion and muscle activity in patients with CP and stiff gait and healthy subjects during stair climbing

Research question

How similar or different do the knee move and the muscles act when walking on level ground and climbing stairs in patients with CP and stiff knee gait compared to healthy subjects?

Methods

12 patients with bilateral CP and stiff knee gait and 25 healthy subjects (norm) were included in the study. A 3D gait analysis on level ground as well as on stairs (5 steps) including electromyography (EMG) was performed.

The norm-distance (ND = [(average patient data − average norm group)/standard deviation of norm group] summed up over the gait cycle) [3] was calculated as a measurement how similar the patients are compared to the healthy subjects. If the value is smaller the patient data are

Results

CP and norm group show significant differences of the ND in knee motion and muscle activity in every condition (see Table 1 and Fig. 1). In downstairs condition the p-values are prominently larger then in level and upstairs walking.

Discussion

Patients with stiff knee gait show clearly different knee motion on level ground compared to their normally developing peers. Surprisingly, the knee pattern is more similar to the norm group when climbing downstairs. Similarly, the pattern of m. rectus femoris and m. vastus lateralis is less dissimilar to the norm when walking downstairs. Potentially the dominant need for excentric and prolonged muscle function in downstairs walking suits the condition of prolonged muscle activation patterns