Background Calcaneal lengthening with allograft is frequently used for the treatment of patients with symptomatic planovalgus deformity; however, the behavior of allograft bone after calcaneal lengthening and the risk factors for graft failure are not well documented. Questions/purposes (1) What proportion of the patients treated with allograft bone had radiographic evidence of graft failure and what further procedures were performed? (2) What are the risk factors for radiographic graft failure after calcaneal lengthening? (3) What patient factors are associated with the magnitude of correction achieved after calcaneal lengthening? Methods Between May 2003 and January 2014, we performed 341 calcaneal lengthenings on 202 patients for planovalgus deformity, the etiology of which included idiopathic, cerebral palsy, and other neuromuscular disease. Of these, 176 patients (87%) had adequate followup for graft evaluation, defined as lateral radiographs taken before and at least 6 months after the index procedure (mean, 18 months; range, 6-100 months) and 117 patients (58%) had adequate followup for the assessment of the extent of correction, defined as weightbearing anteroposterior and lateral radiographs taken before and at least 1 year after the index procedure (mean, 24 months; range, 12-96 months). These patients' results were evaluated retrospectively. The Goldberg scoring system was chosen for demonstration of allograft behavior. A score lower than 6 at 6 months after surgery was defined as radiographic graft failure; the highest possible score was 7 points, and this represented graft incorporation with excellent reorganization of the graft and no loss of height. The patient age, sex, diagnosis, graft material, ambulatory status, and use of antiseizure medication were evaluated as possible risk factors, and we controlled for the interaction of potentially confounding variables using multivariate analysis. Additionally, six radiographic indices were analyzed for their effects on the extent of correction. Results The mean estimated Goldberg score was 6 (SD, 1.14) at 6 months after calcaneal lengthening with 11 feet (4%) classified as radiographic graft failure (Goldberg score \ 6). Of these, four feet (1%) underwent reoperation using an iliac autograft bone resulting from pain and loss of correction. Multivariate analysis showed that the tricortical iliac crest allograft was superior to the patellar allograft (odds ratio [OR], 3.2; 95% confidence interval [CI], 1.1-9.8; p = 0.038) and the possibility of radiographic graft failure was found to increase along with age (OR, 1.2; 95% CI, 1.0-1.3; p = 0.006). Radiographically, the extent of correction was found to decrease with patient age, as

PurposeThis study investigated the correlation between isometric muscle strength, gross motor function, and gait parameters in patients with spastic cerebral palsy and to find which muscle groups play an important role for gait pattern in a flexed knee gait.Materials and MethodsTwenty-four ambulatory patients (mean age, 10.0 years) with spastic cerebral palsy who were scheduled for single event multilevel surgery, including distal hamstring lengthening, were included. Preoperatively, peak isometric muscle strength was measured for the hip flexor, hip extensor, knee flexor, and knee extensor muscle groups using a handheld dynamometer, and three-dimensional (3D) gait analysis and gross motor function measure (GMFM) scoring were also performed. Correlations between peak isometric strength and GMFM, gait kinematics, and gait kinetics were analyzed.ResultsPeak isometric muscle strength of all muscle groups was not related to the GMFM score and the gross motor function classification system level. Peak isometric strength of the hip extensor and knee extensor was significantly correlated with the mean pelvic tilt (r=-0.588, p=0.003 and r=-0.436, p=0.033) and maximum pelvic obliquity (r=-0.450, p=0.031 and r=-0.419, p=0.041). There were significant correlations between peak isometric strength of the knee extensor and peak knee extensor moment in early stance (r=0.467, p=0.021) and in terminal stance (r=0.416, p=0.043).ConclusionThere is no correlation between muscle strength and gross motor function. However, this study showed that muscle strength, especially of the extensor muscle group of the hip and knee joints, might play a critical role in gait by stabilizing pelvic motion and decreasing energy consumption in a flexed knee gait.

3DGAThree-dimensional gait analysis ICC Intraclass correlation coefficient RFT Rectus femoris transfer ROC Receiver operator characteristics AIM The aim of this study was to clarify the method of the Duncan-Ely test and to estimate its interobserver reliability and validity by comparing it with three-dimensional gait analysis (3DGA). METHOD This study included 36 consecutive ambulatory patients with cerebral palsy (CP)who underwent preoperative 3DGA. The Duncan-Ely test was performed during three different velocities (slow, gravity, and fast). The interobserver reliability was assessed by three examiners. The results of the test were compared with kinematic variables derived from the gait analysis to assess the sensitivity and specificity of the test. The cut-off value was determined at the point of trade-off between the highest sensitivity and specificity. RESULTSThe intraclass correlation coefficient measuring interobserver reliability of the Duncan-Ely test was greatest during fast velocity (0.819). The sensitivity and specificity of the test during gravity velocity for knee range of motion total were 63.0% and 100% respectively, with a cut-off value of 78.3°. The sensitivity and specificity of the test during fast velocity for knee range of motion total were 66.7% and 100% respectively, with a cut-off value of 65°. INTERPRETATIONThe Duncan-Ely test shows excellent reliability in fast knee-flexion velocity, and good sensitivity and specificity compared with 3DGA during physical examination as a preoperative assessment of rectus femoris spasticity in patients with CP.Stiff-knee gait, which is defined as a restricted arc in knee motion during swing, 1 is a common gait disorder in ambulatory patients with cerebral palsy (CP), regardless of the anatomical type of CP.2 Stiff-knee gait results in foot clearance problems and reduces gait velocity and step length. Some patients complain of their shoes wearing out rapidly. Although there is still controversy, 3 it is now widely accepted that one of the causes of stiff-knee gait in patients with CP is spasticity of the rectus femoris. [4][5][6][7] Since rectus femoris transfer (RFT) has been recommended for restoring knee motion during the swing phase, it is now the standard surgical treatment for stiff-knee gait in patients with CP and is frequently performed as part of a single-event multilevel surgery. 1,5,8,9 Before single-event multilevel surgery, a physical examination is essential to assess the patient's physical status. The Duncan-Ely test, among others, has been recommended as a clinical tool for assessing rectus femoris spasticity. 10 In the classic Duncan-Ely test, the examiner passively flexes the knee rapidly while the patient lies prone in a relaxed state. The test is considered positive if the patient simultaneously flexes their ipsilateral hip or if resistance is felt by the examiner during passive knee flexion.10,11 A positive test result reflects the velocitydependent spasticity of the rectus femoris muscle during the rapid movement test as well as mu...