Characteristics of surface electromyogram signals after Pemberton pelvic osteotomy combined with femoral osteotomy in children with unilateral developmental dysplasia of the hip

This study aimed to assess the surface electromyogram (sEMG) signal characteristics of the muscle around the hip joint after Pemberton osteotomy in children with unilateral developmental dysplasia of the hip (DDH). A total of 21 children with unilateral DDH who had received Pemberton osteotomy were selected as the DDH group, and 21 healthy children of the same age were selected as the control group. The children in both groups were tested using sEMG, the Root mean square (RMS) values of the tensor fascia lata, rectus femurs, and medial head of the hamstring and gluteus maximum on both sides in standing and walking status were recorded. The value on the affected side in the DDH group was compared with the value on the healthy side himself and the value in the control group. The mean postoperative follow-up in the DDH group was 27.76 +/- 24.30 months. The RMS value of the affected gluteus maximum muscle in the DDH group was significantly larger while standing (P < 0.05), the RMS value of bilateral tensor fascia lata muscle was significantly larger while walking (P < 0.05), and the RMS value of the affected hamstring muscle medial head was significantly less in the DDH group compared with the control group (P < 0.05). An asymmetry and compensatory increase in the sEMG activity of the muscles around the hip joint when standing and walking was noted in children with unilateral DDH who underwent Pemberton osteotomy combined with a femoral osteotomy. The rehabilitation training of the muscles around the hip joint after unilateral DDH should be strengthened.