Gait analysis of patients with piriformis muscle syndrome compared to healthy controls.

BACKGROUND

Piriformis muscle syndrome (PMS) is a condition that can causes local buttock pain and tenderness. The symptoms of PMS are related to the hip joint position and may affect repetitive daily tasks such as walking.

OBJECTIVES

What is the difference between the gait characteristics of patients with PMS and those of matched-healthy controls?

DESIGN

Observational study.

METHODS

Thirty patients with PMS and 30 age-, sex-, and height-matched healthy participants underwent three-dimensional walking analysis.

RESULTS

The results showed no significant differences in the spatiotemporal characteristics of gait between the groups (p > 0.1). The PMS group flexed the hip joint significantly more (-7.2 [-11.9 to -2.2], p = 0.003) and extended the hip joint to a lesser degree (-2.48 [-4.91 to -0.5], p = 0.04) than the control group. Patients with PMS needed a statistically significantly longer time to reach the peak angles of hip internal (1.3 [1 to 1.9], p = 0.003) and external (5.5 [0.9 to 10.1], p = 0.01) rotations during the gait cycle. Further, the results showed that the sagittal range of motion of the knee joint was significantly lesser in patients with PMS than in controls (3.45 [0.4 to 6.4], p = 0.02).

CONCLUSIONS

Patients with PMS seem to have different kinematic changes during level walking. Changing the peak flexion and extension of the hip joint is considered a strategy to enable pain-free gait in patients with PMS. Further, the knee kinematics are modified consequent to the change of hip joint kinematics.