David H. Sutherland

Double-blind study of botulinum A toxin injections into the gastrocnemius muscle in patients with cerebral palsy

The purpose of this study was to quantify the gait of subjects receiving two injections of either botulinum A toxin or saline vehicle into the gastrocnemius muscle(s). The study group consisted of cerebral palsy patients who walked with an equinus gait pattern. This study was a randomized, double-blinded, parallel clinical trial of 20 subjects. All were studied by gait analysis before and after the injections. There were no adverse effects. Peak ankle dorsiflexion in stance and swing significantly improved in subjects who received the drug and not in controls. Results of this double blind study give support to the short term efficacy of botulinum toxin A to improve gait in selected patients with cerebral palsy.

Gait asymmetry in patients with limb-length inequality

One of the problems facing the clinician is the differentiation between functional and structural limb-length inequality. This study investigated 20 subjects (mean age, 9.0 +/- 3.9 years) with documented limb-length inequalities to determine the magnitude of discrepancies that result in gait abnormalities. The subjects were asked to walk on an 8-m walkway at a self-selected free pace. The contact time, first and second force peaks, and loading and unloading rates of the vertical ground-reaction force were measured for both limbs. These parameters were predictive for quantification of gait asymmetry. The asymmetry of these parameters increased as the limb-length inequality increased. In general, a limb-length inequality > 2.0 cm (3.7%) resulted in gait asymmetry that was greater than that observed in the normal population. However, the amount of asymmetry varied for each individual. A static examination can document an anatomic deformity, but this deformity may be compensated for by functional adaptations. An analysis of the patients gait should be performed to identify asymmetries during ambulation. Dynamic gait findings, such as demonstrated in this study, are needed to support static measurements.

Evaluation of CT scans and 3-D reformatted images for quantitative assessment of the hip.

Hip measurements using three-dimensional (3-D) images and computed tomography (CT) scans were evaluated. The 3-D measurements proved more accurate than CT measurements of femoral and acetabular anteversion. Additionally, accurate 3-D measurements (> 99%) of the femoral neck-shaft angle were provided. Acetabular anteversion determinations by CT scans were systematically decreased as pelvic flexion increased, whereas accuracy was > 96% with 3-D images. The 3-D software allows image rotation in all three reference planes, which minimizes positional errors. A case study is provided to exemplify the shortcomings of conventional imaging techniques and the utility of the quantitative 3-D protocol.

Injection of botulinum A toxin into the gastrocnemius muscle of patients with cerebral palsy: a 3-dimensional motion analysis study

Abstract Botulinum A toxin (BOTOX ® ) was injected into the gastrocnemius muscle of 26 cerebral palsy subjects with equinus gait. All subjects were equinus walkers without fixed contracture of the triceps-surae muscle. Injections were performed at 3 month intervals, if needed, as determined by the treating clinician. There were 14 subjects with spastic hemiplegia, 11 subjects with spastic diplegia and 1 subject with spastic quadriplegia. In the case of those subjects with bilateral equinus gait the dose was divided and given into both the right and left gastrocnemius muscle. Gait analysis data was collected prior to the first injection and subsequently at 3 month intervals for 1 year. Kinematic and electromyographic data was obtained. This data was analyzed to provide objective information about the outcome of treatment. Four subjects moved away and were lost to follow-up. Seven subjects left the study to have surgery. The data collected revealed statistically significant improvements in dynamic ankle dorsiflexion in both stance and swing phases, stride length, and electromyography of the tibialis anterior. There were no complications. While the results of this study are promising, additional prospective studies are needed to determine the feasibility of preventing muscle contractures over a longer time period. Furthermore, there is a need for inclusion of other muscles in future research. Future research should also compare BOTOX ® treatment with alternative methods of dealing with muscle spasticity such as: casting, orthotic devices, physical therapy, selective dorsal rhizotomy, and surgical lengthening.

Femoral anteversion and neck-shaft angle in children with cerebral palsy.

A database of femoral anteversion and neck-shaft angle was compiled of measurements made by the trigonometric fluoroscopic method of 147 patients (267 hips) with cerebral palsy. The angles of femoral anteversion were similar at early ages between healthy children and children with cerebral palsy. However, as the age of the children increased, those with cerebral palsy showed little change in anteversion angle, whereas the healthy children had progressively decreasing angles of femoral anteversion as they approached adulthood. The neck-shaft angle was increased significantly in children with cerebral palsy compared with the angles of healthy children. Patients who were ambulatory were shown to have an increased angle of femoral anteversion and a decreased neck-shaft angle compared with nonambulatory patients. There was no significant difference in angles among the various distributions of involvement, including patients with diplegia, hemiplegia, and quadriplegia.

Psoas release at the pelvic brim in ambulatory patients with cerebral palsy: Operative technique and functional outcome

Seventeen patients with cerebral palsy (29 hips) underwent psoas recession at the pelvic brim. The operative technique was a direct anterior approach, lateral to the femoral sheath. There were no infections or nerve or arterial injuries. After surgery, clinical examination revealed that fixed hip-flexion contractures decreased significantly in all patients. All of the subjects retained the ability to flex the hip against gravity and against manual resistance. All of the subjects underwent pre- and postoperative gait analysis. Stance-phase dynamic minimum hip flexion decreased significantly. Dynamic pelvic tilt improved to a statistically significant level for the younger children but did not for the group as a whole. There was less improvement with increasing age. Step length was significantly increased and cadence significantly decreased in all patients. We conclude that psoas recession at the pelvic brim, by using the anterior approach, lateral to the femoral sheath, is a safe, reliable, and effective procedure for children with cerebral palsy who have excessive anterior pelvic tilt and excessive dynamic hip flexion or hip-flexion contracture.

Kinematic and kinetic analysis of distal derotational osteotomy of the leg in children with cerebral palsy.

Patients with cerebral palsy often develop rotational deformities of the lower extremities. These deformities may be caused by abnormal muscle tone, soft-tissue contractures, or bony malalignment. When rotational deformity persists after correction of the soft-tissue components, bony-realignment procedures are warranted to improve gait in ambulatory patients. We performed a retrospective review of 10 ambulatory children with cerebral palsy and tibial torsion who underwent 13 distal tibial and fibular derotation osteotomies. Preoperative and postoperative three-dimensional gait analysis were used to determine the effect of distal tibial and fibular derotation osteotomy on tibial rotation, foot-progression angle, gait velocity, and moments about the ankle. Mean tibial rotation and foot-progression angle were significantly improved by the procedure. Gait velocity improved but not significantly. Moment data demonstrated a trend toward normal. This study demonstrates that the derotational distal tibial and fibular osteotomy stabilized with percutaneous crossed Kirschner wires is a safe, reliable, and effective procedure for correcting rotational deformities of the leg in patients with cerebral palsy.

Quantitative analysis of hip dysplasia in cerebral palsy: a study of radiographs and 3-D reformatted images.

Cerebral palsy patients (31 hips) were evaluated using radiographic and three-dimensional (3-D) images to quantify hip anatomy. The 3-D images overcome distortions caused by joint contractures. Changes were more pronounced in the non-ambulators and characterized by shallow sockets with increased neck-shaft angles. These hips tended to subluxate in a posterior-superior direction and most had defects in the femoral heads. Ambulators had increased femoral anterversion but other hip parameters tended to improve with age. The 3-D measures of roof steepness and socket depth were found to correlate strongly with radiographic parameters of subluxation.

Rectus femoris release in selected patients with cerebral palsy: a preliminary report.

Two theories concerning the effects of surgical release of the proximal origins of the rectus femoris in spastic patients are (1) that release reduces hip flexion contracture and lumbar lordosis and diminishes crouch, and (2) that release primarily enhances early swing‐phase knee flexion.

Three-dimensional characteristics of cartilaginous and bony components of dysplastic hips in children: Three-dimensional computed tomography quantitative analysis

A cartilage-viewing technique was developed to overcome the shortcoming of not seeing the cartilaginous components, believed to play more important role than the osseous components in childrens hips, with computed tomography. This technique was applied to 25 dysplastic hips in children younger than 10 years to evaluate their global and local deficiencies. The findings helped us to understand more about their individual problems. To quantify the three-dimensional (3-D) parameters of acetabular anatomy and femoral head coverage, a measuring technique was developed based on digitization of the 3-D coordinates and fitting of every component of the hip. The improved images and the quantified parameters were expected to aid the planning, formulation, and even simulation of individualized surgical treatment for children with developmental dysplasia of the hip.