Sandra W. Dennis

The effects of fixed and articulated ankle-foot orthoses on gait patterns in subjects with cerebral palsy.

Twenty-one subjects with spastic diplegic cerebral palsy were studied to quantify the effects of fixed and articulated ankle-foot orthoses (AFOs) on gait and delineate criteria for their use. Children underwent gait analysis under three conditions, fixed AFOs (FAFOs), articulated AFOs (AAFOs), and shoes alone. Greater dorsiflexion occurred at initial contact with both FAFOs and AAFOs than shoes alone. Dorsiflexion at terminal stance was greatest in AAFOs. Plantarflexor power generation at preswing was preserved in AAFOs. No differences were found in knee position during stance. Knee-extensor strength was positively related to knee extension during stance. No relationships were found between dorsiflexion range of motion, calf spasticity and strength, and peak dorsiflexion during stance. AAFOs are appropriate for subjects with varying degrees of calf spasticity, as long as adequate passive range of motion is available. These findings can be applied primarily to children who do not have a preexisting tendency to crouch.

Variability in gait analysis interpretation.

The purpose of this study was to assess the reliability of interpretation of gait analysis data between physicians and institutions. Gait analysis data from seven patients were reviewed by 12 experienced gait laboratory physicians from six institutions. Reviewers identified problems and made treatment recommendations based on the data provided. Agreement among physicians for the most commonly diagnosed problems was slight to moderate (kappa range, 0.14–0.46). Physicians agreed on identification of soft tissue more than bony problems (intraclass correlation, 0.56 vs. 0.37). Variability regarding surgical recommendations for soft-tissue procedures (kappa range, 0.20–0.64) was similar to that for diagnosis of both soft-tissue and bone problems, although recommendation for hamstring lengthening showed substantial agreement (kappa = 0.64). There was less agreement in recommendation of osteotomies (kappa range, 0.13–0.22). Physicians agreed more on the number of soft-tissue procedures than bone procedures recommended (intraclass correlation, 0.65 vs. 0.19). There was an interinstitutional difference in the frequency of soft-tissue (p = 0.0152) and osseous problem identification (p = 0.0002), as well as in the frequency of recommendations for soft-tissue surgery (p = 0.0004) and osteotomies (p < 0.0001). Although gait analysis data are themselves objective, this study demonstrates some subjectivity in their interpretation. The interobserver variability reported here is similar to that reported for established classification systems of various orthopedic conditions.

Impact of postoperative gait analysis on orthopaedic care.

The impact of postoperative gait analysis on the ongoing orthopaedic care of 38 consecutive patients with a static encephalopathy was evaluated. Of the 38 postoperative gait analyses, 32 (84%) resulted in recommendations of a change in patient care. Surgery was recommended in 16 of 38 (42%) cases, bracing in 20 (53%) cases, and specific physical therapy regimens in eight (21%) cases. Eleven of the 38 (29%) patients had changes recommended in at least two of the three areas (surgery, bracing, and therapy). The results of this study suggest that postoperative gait analysis serves not only as a measure of treatment outcome, but also as a useful tool in planning ongoing care for these patients.

Outcomes of lower extremity orthopedic surgery in ambulatory children with cerebral palsy with and without gait analysis: Results of a randomized controlled trial

This study examined the impact of gait analysis on surgical outcomes in ambulatory children with cerebral palsy (CP) through a randomized controlled trial. 156 children with CP (94 male; age 10.2 ± 3.7 years) underwent gait analysis and were randomized to two groups: Gait Report group (N = 83), where the referring surgeon received the patients gait analysis report, and Control group (N = 73), where the surgeon did not receive the gait report. Outcomes were assessed pre- and 1.3 ± 0.5 years post-operatively. An intent-to-treat analysis compared outcomes between the two groups. Outcome measures included the Gillette Functional Activity Questionnaire (FAQ), Gait Deviation Index (GDI), oxygen cost, gross motor function measure, Child Health Questionnaire (CHQ), Pediatric Outcomes Data Collection Instrument (PODCI), and Pediatric Evaluation and Disability Inventory. The outcomes that differed significantly between groups were change in health from the CHQ, which was rated as much better for 56% (46/82) of children in the Gait Report group compared with 38% (28/73) in the Control group (p = 0.04), and upper extremity physical function from the PODCI. Gait outcomes (FAQ and GDI) improved more when over half of the recommendations for a patient were followed or the recommended extent of surgery (none, single, or multi-level) was done (p ≤ 0.04). On average, however, only 42% of the recommendations were followed in the Gait Report group, compared with 35% in the Control group (p = 0.23). This is much less than the >85% reported in previous studies and may account for the lack of differences between groups for some of the outcome measures.

Comparison of 2 Orthotic Approaches in Children With Cerebral Palsy

Purpose: To compare dynamic ankle-foot orthoses (DAFOs) and adjustable dynamic response (ADR) ankle-foot orthoses (AFOs) in children with cerebral palsy. Methods: A total of 10 children with cerebral palsy (4-12 years; 6 at Gross Motor Function Classification System level I, 4 at Gross Motor Function Classification System level III) and crouch and/or equinus gait wore DAFOs and ADR-AFOs, each for 4 weeks, in randomized order. Laboratory-based gait analysis, walking activity monitor, and parent-reported questionnaire outcomes were compared among braces and barefoot conditions. Results: Children demonstrated better stride length (11-12 cm), hip extension (2°-4°), and swing-phase dorsiflexion (9°-17°) in both braces versus barefoot. Push-off power (0.3 W/kg) and knee extension (5°) were better in ADR-AFOs than in DAFOs. Parent satisfaction and walking activity (742 steps per day, 43 minutes per day) were higher for DAFOs. Conclusions: ADR-AFOs produce better knee extension and push-off power; DAFOs produce more normal ankle motion, greater parent satisfaction, and walking activity. Both braces provide improvements over barefoot.

Prediction of postoperative gait velocity in cerebral palsy.

Preoperative and postoperative gait analyses were reviewed for 47 patients with cerebral palsy in an attempt to ascertain predictors of surgical outcome as measured by gait velocity. Higher postoperative velocity correlated with higher preoperative velocity and younger age. Observed velocities in older children were smaller than predicted values. Older children showed either an average decline in velocity from normal for age or no change. Younger children showed an average increase in velocity toward normal for their age. Diagnosis, type of surgery, number of procedures performed and level of ambulation preoperatively were not predictive of postoperative velocity. These results suggests that gait velocity cannot be reliably increased in all children with cerebral palsy undergoing surgery, especially those older than age 12.

Comparison of lateral shuffle and side-step cutting in young recreational athletes

This study compared three-dimensional (3-D) hip and knee kinematics and kinetics between lateral shuffle and side-step cutting movements to determine whether the simpler lateral shuffle movement can be used in place of cutting to assess knee injury risk. A total of 78 patients (52 female) and 34 controls (16 female) aged 8-19 years performed lateral shuffle and 45° side-step cutting movements. Hip and knee kinematics and kinetics between initial contact and peak knee flexion were calculated using the Plug-in-Gait model and compared between activities using Pearsons correlation and paired t-tests. Peak knee valgus angle correlated strongly (r=0.86, p<0.0001), while minimum (r=0.25, p=0.0001) and peak hip abduction (r=0.24, p=0.0003), and peak hip internal rotation (r=0.33, p<0.0001) correlated only weakly between the two activities. Peak external knee valgus moment (r=0.32, p<0.0001) and average external knee (r=0.42, p<0.0001) and hip (r=0.37, p<0.0001) flexion moments correlated weakly to moderately between activities. Subjects were more internally rotated (3.6°, p<0.0001) and less abducted (16.7° and 17.3° for minimum and maximum, p<0.0001) at the hip during cutting, with higher hip (0.12, p<0.0001) and lower knee (-0.02, p=0.0001) non-dimensional flexion moments. These results suggest that the lateral shuffle movement may be useful for evaluating knee valgus, particularly during initial visual assessment. However, the lateral shuffle may not be challenging enough to reveal poor neuromuscular control over hip ab/adduction and rotation, necessitating follow-up assessment of cutting, ideally using 3-D motion analysis.