Hamstring shortening: postural defect or congenital contracture

The clinical appearance of hamstring shortening in 10 patients referred with diagnosis of asymmetry of the trunk, scoliosis, postural defect, strange gait, and back pain is reported. Additionally, an assessment of knee extension deficit (KED) angle in 575 healthy children (4-15 years of age) was performed. The mean KED angle in the group of healthy children was 35 degrees (SD = 14 degrees). The border between norm and disease was defined as a mean + 2 SD and equaled 63 degrees. A KED angle greater than 60 degrees occurred in 10% of normal children. There was no correlation between age and a value of KED angle. In the study group, KED angle greater than 40 degrees was more frequent in boys. A correlation between disorders within musculoskeletal system and greater KED angle was found. These disorders were more frequent in children with asymmetrical KED angle. In our opinion, the border value of the KED angle is not a good differentiating factor between hamstring shortening and contracture because it does not explain the cause of the disorder.