Article

This study was undertaken to determine the effect of distal hamstring lengthening
(DHL) on hip and knee sagittal kinematics, and to investigate the validity of
modeled hamstring length for clinical use. Patient group consisted of 28 patients
(56 limbs, mean age 7.4 years) with spastic diplegia who underwent bilateral DHL
and tendo-Achilles lengthening with/without rectus femoris transfer (RFT)
(DHL+RFT subgroup, 40 limbs; DHL subgroup, 16 limbs). Kinematic data was obtained
by gait analysis, and hamstring lengths were obtained using a musculoskeletal
modeling technique. Postoperatively, knee extension improved (p<0.001) without
aggravating anterior pelvic tilt (p=0.565). However, DHL aggravated anterior
pelvic tilt in the DHL subgroup (2.2 degrees, p=0.011). In terms of concurrent
validity, hamstring length was found to be correlated with mean pelvic tilt
(r=0.798, p<0.001) and popliteal angle (r=-0.425, p=0.001), but the correlation
between hamstring length and knee flexion at initial contact was minimal
(r=0.068, p=0.753). In terms of construct validity, DHL did not lengthen mean
hamstring length (p=0.918). In conclusion, DHL appeared to significantly improve
knee motion in patients with spastic diplegia. Furthermore, DHL did not increase
pelvic tilt, when performed with RFT. Modeled hamstring length is believed to
have limited validity in patients with cerebral palsy, because it does not
reflect knee kinematics or postoperative change when DHL was combined with
multilevel surgery.

Langue : ANGLAIS