Three-dimensional analysis of trunk compensation during gait after internal hemipelvectomy: A case report

Internal hemipelvectomy is a limb-salvage procedure used to treat aggressive pelvic bone tumors. Depending on the extent of pelvic resection, the procedure can substantially alter pelvic stability, muscle attachment sites, and lower-extremity loading during gait. These structural changes are associated with altered movement patterns during walking, which may influence the ability to maintain functional ambulation. Although gait deviations following hemipelvectomy have been reported, the role of trunk motion within these altered gait patterns remains poorly understood.

What trunk and lower-extremity gait patterns are observed during walking in an adolescent following type I, II, and III internal hemipelvectomy with limb salvage?

A 15-year-old adolescent post I-III internal hemipelvectomy without reconstruction at age 11 underwent three-dimensional motion analysis during walking. Gait was evaluated under two conditions: barefoot and with a solid ankle-foot orthosis (AFO) with shoe lift to address leg-length discrepancy. Trunk, pelvic, lower-extremity kinematics, joint moments and ground reaction forces were analyzed.

The participant demonstrated exaggerated posterior trunk pitch and increased lateral trunk displacement during stance, accompanied by reduced hip, knee, and ankle excursion on the surgical limb. Despite diminished lower-extremity motion, altered sagittal-plane joint moments, and reduced propulsive impulses on the surgical limb, independent ambulation was maintained.

These findings suggest an association between exaggerated and asymmetrical trunk motion with preserved ambulation despite reduced lower-extremity mechanics; however, the specific relationship between trunk motion and center-of-mass control was not directly quantified.