Inertial measurement unit (IMU)-based gait analysis can be used to quantitatively analyze the bilateral coordination and gait asymmetry (GA). The purpose of this study was to investigate changes in bilateral coordination and GA due to gait speed using an IMU based gait analysis and identify spatiotemporal factors affecting bilateral coordination and GA. Eighty healthy adults (40 men and 40 women) participated in the study. The mean age was 26.2 years, and the mean body mass index was 22.8 kg/m². Three different walking speeds (80%, 100%, and 120% of preferred walking speed) on a treadmill were applied for 1 min of continuous level walking using a shoe-type IMU-based gait analysis system. The phase coordination index (PCI) and GA were calculated on three different walking speeds. Several variables (gait speed, height, body mass index, cadence, and step length) were analyzed as possible factors affecting the PCI and GA. Bilateral coordination and GA improved during fast walking (p = 0.005 and p = 0.019, respectively) and deteriorated during slow walking (p<0.001 and p = 0.008, respectively), compared with the participants’ preferred walking speeds. The correlation analysis revealed that PCI was negatively correlated with step length at each walking condition and lower gait speed was negatively correlated with PCI and GA during slow walking. Both bilateral coordination and GA had a negative linear relationship with gait speed, showing an improvement in the fast walking condition and deterioration in the slow walking condition. Step length was the factor associated with the change in the bilateral coordination.

The purpose of this study was to understand the pros and cons of the lengthening nails which have their own mechanical mechanism; we propose a classification for “device-related complications” arising from mechanical properties of the nail itself. From March 2010 to March 2014, 115 segments of lower limb lengthening were performed using intramedullary lengthening nails (35 ISKD, 34 PRECICE1, and 46 PRECICE2). Device-related complications were sorted into three categories according to a new classification: distraction control-related (type I), stability related (type II), and other device-related (type III); these were subdivided using Paley’s concept of problems (a), obstacles (b), and sequel (c). Most common complications were distraction mechanism issues (type I) in ISKD and mechanical strength related ones (type II) in PRECICE1 and PRECICE2. Sixty percent (21/35) of ISKD had device-related problems. In PRECICE1 group, 8.8% (3/34) had device-related problems, and 8.8% (3/34) showed device-related obstacle. In PRECICE2, forty-four percent (20/46) had device-related problems. In conclusion, a new classification showed more clearly the differences of mechanical characteristics of different nails. The most essential thing of future lengthening nail development is minimizing the types I and II complications. Further study is necessary to compare the mechanical strength and stability of lengthening nails.

The aims of this study were to report functional outcomes of salvage procedures for patients with cerebral palsy (CP) who have chronic dislocation of the hip using validated scoring systems, and to compare the results of three surgical techniques.We reviewed 37 patients retrospectively. The mean age at the time of surgery was 12.2 years (8 to 22) and the mean follow-up was 56 months (24 to 114). Patients were divided into three groups: 14 who underwent proximal femoral resection arthroplasty (PFRA group 1), ten who underwent subtrochanteric valgus osteotomy (SVO group 2), and 13 who underwent subtrochanteric valgus osteotomy with resection of the femoral head (SVO with FHR group 3). All patients were evaluated using the Caregiver Priorities and Child Health Index of Life with Disabilities (CPCHILD) and the Pediatric Quality of Life Inventory (PedsQL).Significant improvements occurred in most CPCHILD and PedsQL subsection scores following surgery in all patients, without significant differences between the groups. There were 12 post-operative complications. Less severe complications were seen in group 1 than in groups 2 and 3.Salvage surgery appears to provide pain relief in patients with CP who have painful chronic dislocation of the hip. The three salvage procedures produced similar results, however, we recommend the use of PFRA as the complications are less severe.Take home message: Salvage surgery can be of benefit to patients with CP with chronic painful hip dislocation, but should be limited to selected patients considering complications.Cite this article: Bone Joint J 2016;98-B:137–43.

Background: The aim of this study was to compare the outcomes of angular deformity correction by percutaneous hemiepiphysiodesis using transphyseal screw (PETS) or tension-band plating (TBP) in growing children with idiopathic genu valgum with emphasis on the rate of deformity correction. Methods: We retrospectively reviewed cases of hemiepiphysiodesis for angular deformity in lower extremities between 2009 and 2014. A total of 90 limbs in 33 patients received PETS and 60 limbs in 24 patients received TBP. Angular measurements were compared preoperatively and at the time of hardware removal. The amount and rate of angular deformity correction were compared between the 2 groups. Potential factors affecting correction velocity were investigated using multivariate analysis. Results: Angular correction was achieved in all patients. The mean rate of correction was more rapid with PETS than with TBP at both the distal femur (0.92 vs. 0.64 deg./mo, respectively; P<0.001) and proximal tibia (0.72 vs. 0.55 deg./mo, respectively; P=0.019). Multivariate analysis showed that the used implant significantly affected the rate of correction: PETS demonstrated faster correction velocity than TBP (−0.26, 95% confidence interval, −0.35 to −0.17, P<0.001). Conclusions: Both PETS and TBP techniques result in satisfactory correction of coronal angular deformity in patients with idiopathic genu valgum. However, the observed rate of correction was faster with PETS than TBP. Correction with PETS, rather than TBP, may better serve patients near skeletal maturity. Level of Evidence: Level III—retrospective comparative series.

This study aimed to evaluate the effect of levodopa on the phase coordination index (PCI) and gait asymmetry (GA) of patients with Parkinson’s disease (PD) and to investigate correlations between the severity of motor symptoms and gait parameters measured using an inertial sensor. Twenty-six patients with mild-to-moderate-stage PD who were taking levodopa participated in this study. The Unified Parkinson’s Disease Rating Scale part III (UPDRS III) was used to assess the severity of motor impairment. The Postural Instability and Gait Difficulty (PIGD) subscore was calculated from UPDRS III. Patients were assessed while walking a 20-m corridor in both “OFF” and “ON” levodopa medication states, and gait analysis was performed using inertial sensors. We investigated the changes in gait parameters after taking levodopa and the correlations between UPDRS III, PIGD, and gait parameters. There was a significant improvement in PCI after taking levodopa. No significant effect of levodopa on GA was found. In “OFF” state, PCI and GA were not correlated with UPDRS III and PIGD. However, in “ON” state, PCI was the only gait parameter correlating with UPDRS III, and it was also highly correlated with PIGD compared to other gait parameters. Significant improvement in bilateral-phase coordination was identified in patients with PD after taking levodopa, without significant change in gait symmetricity. Considering the high correlation with UDPRS III and PIGD in “ON” states, PCI may be a useful and quantitative parameter to measure the severity of motor symptoms in PD patients who are on medication.

The aim of this study was to investigate the relationship between accessory navicular (AN) and flat foot and to evaluate the association between flat foot and the symptoms of patients with AN. We enrolled 196 patients with painful or asymptomatic AN in this study. Patients who were older than 18 years or who had no weight-bearing radiographs of the feet were not included. Another 46 normal participants were used as a control group. The AN group was divided into 3 subgroups: a group with asymptomatic AN; a symptomatic group that had not undergone excision; and a symptomatic group that had undergone surgery. Seven radiographic indices were measured including calcaneal pitch angle, tibiocalcaneal angle, talocalcaneal angle, naviculocuboid overlap, talonavicular coverage angle, lateral talo-first metatarsal angle, and AP talo-first metatarsal angle. Groups were compared regarding age, sex, presence of pain at the time of surgery, and radiographic parameters. The calcaneal pitch angle in the AN group was significantly smaller than that of controls (P=0.004). Naviculocuboid overlap (P=0.001), talonavicular coverage angle (P<0.001), lateral talo-first metatarsal angle (P=0.014), and AP talo-first metatarsal angle (P<0.001) were significantly larger in the AN group than in controls. No significant radiologic differences were seen between patients with symptomatic and asymptomatic AN. No significant radiographic differences were found between the groups of patients who had and who had not had bone excised. AN associated with radiographic parameters felt to be representative of a flat foot; however, the degree of flat foot was not associated with the development and severity of symptoms in patients with AN.