INTRODUCTION: Obesity is associated with various musculoskeletal disorders, including low back pain (LBP). Gait can be also affected in these subjects but no quantitative data are today available.
Aim: to quantify parameters of gait in obese LBP subjects.
METHODS: Population: 8 LBP obese female patients, (LBP; age: 40.5+10.1 years; BMI: 42.39+5.47 Kg/m2), 10 obese female subjects (OBE; age: 33.6+5.2 years; BMI: 39.26+2.39 Kg/m2) and 20 healthy females (CON; age: 33.4+9.6 years; BMI: 22.8+3.2 Kg/m2).
Exclusion criteria: secondary LBP, osteoporosis, osteoarthritis or disease precluding physical exercise.
Assessment: 3D‐Gait Analysis using an optoelectronic system with 6 cameras (VICON) and two force platforms. Spatio‐temporal, kinematic and kinetic parameters were measured to compare groups.
Statistical analysis: Kolmogorov‐Smirnov test and post‐hoc (p< 0.05).
RESULTS: LBP showed longer stance duration and reduced step length (63%; 0.33 m) if compared to obese subjects (62%; 0.38) and CON (59%; 0.88; p<0.05). Hip flexion were increased in LBP and OBE with respect to CON (46° and 44° vs 27; p<0.05). LBP group showed reduced knee flexion during swing phase in comparison to obese and CON (55° vs 58° and 60°, p<0.05). LBP exhibited plantarflexed position at initial contact and a limited dorsiflexion during stance and swing phase than obese subjects. Both LBP and obese group revealed a limited ankle power generation at push‐off if compared to CON; hip exhibited high power generation during stance in both LBP and obese subjects, but LBP subjects revealed higher hip power peak than obese group.
DISCUSSION: LBP and obese showed an abnormal gait pattern, more evident in LBP that showed a less stable gait and abnormal strategy at knee and in particular at ankle joint in terms of kinematics. This may be an antalgic strategy, but it's also related to overweight.