Internal Derotation Osteotomy of the Tibia: Pre- and Postoperative Gait Analysis in Persons with High Sacral Myelomeningocele

Abstract

Rotational deformities of the lower extremities are common in patients with myelomeningocele. In these situations, surgical correction is often necessary. We conducted a retrospective review of eight ambulatory patients with high sacral myelomeningocele and external tibial torsion who underwent 10 distal tibia and fibular internal derotation osteotomies. All patients had an increased valgus knee stress preoperatively. Pre- and postoperative three-dimensional gait analysis was used to evaluate coronal plane knee moments and dynamic sagittal plane knee motion. Postoperatively, a significant improvement in the abnormal internal knee varus moment (p < 0.005) as well as a significant increase in the stance phase knee extension (p < 0.01) was seen. Three patients had resolution of preoperative knee pain. We believe that patients with increased knee stress secondary to excessive external tibial torsion will benefit from a tibial derotation osteotomy that could delay or prevent the onset of late degenerative changes about the knee.

Orthopedic management of spina bifida. Part I: Hip, knee, and rotational deformities

“…It is especially useful in pre-operative planning for ambulatory patients and in quantitatively assessing surgical results. Its use has been reported in the literature for analyzing many manifestations of spina bifida, including hip subluxation/ dislocation, lower extremity contractures, and rotational abnormalities [21][22][23][24][25]. Clinical evaluation of patients with spina bifida is complex and involves multiple inter-related levels of deformity.…”

“…Gait analysis has allowed the identification of multiple factors contributing to abnormal valgus stress, including rotational malalignment of the femur, femoral anteversion in association with excessive external tibial torsion, excessive trunk and pelvic movement, and knee flexion contractures [10,24,36,37]. Surgical correction of excessive rotational deformities is indicated in patients over the age of 6 years and has been shown to lead to a significant improvement in knee stress and pain and may prevent the onset of late degenerative changes [21]. If knee valgus is associated with knee flexion contracture or hindfoot valgus, the surgical correction of these deformities is required at the same setting.…”

“…Initially, ambulatory patients can be treated conservatively with orthoses such as AFOs with twister cables. However, many ambulatory patients will go on to develop severe femoral and tibial rotational deformities, which can lead to labored gait, difficulty with orthotic fitting resulting in skin ulceration, and pain [21]. For ambulatory patients, the goal is to minimize bracing requirements while achieving as normal a gait as possible [38].…”

“…Additionally, derotation osteotomy may delay or prevent the onset of late degenerative changes about the knee for patients with excessive external tibial torsion [21]. One study found increased valgus knee stress in eight out of eight patients with external tibial torsion [21].…”

Coronal Plane Knee Moments Improve After Correcting External Tibial Torsion in Patients With Cerebral Palsy

“…The resultant gait abnormalities and pain may occur in patients with myelodysplasia [6,8,28] with potential long-term effects of arthritis [29]. Similar findings were described in those with no neuromuscular disorder [5,14,16].…”