Background: The purpose of this study was to analyze kinematic trunk motion data in normal adults and to investigate gender effect. Methods: Kinematic trunk motion data were obtained for 20 healthy subjects (11 men and 9 women; age from 21 to 40 years) during walking a 9 m long lane at a self selected speed, namely, motions in the sagittal (tilt), coronal (obliquity), and transverse (rotation) planes, which were all expressed as motions in global (relative to the ground) and those in pelvic reference frame (relative to pelvis), i.e., tilt (G), obliquity (G), rotation (G), tilt (P), obliquity (P), rotation (P). Results: Range of tilt (G), obliquity (G) and rotation (G) showed smaller motion than that of tilt (P), obliquity (P) and rotation (P), respectively. When genders were compared, female trunks showed a 5 degree more extended posture during gait than male trunks (p = 0.002), which appeared to be caused by different lumbar lordosis. Ranges of coronal and transverse plane motion appeared to be correlated. In gait cycle, the trunk motion appeared to counterbalance the lower extremity during swing phase in sagittal plane, and to reduce the angular velocity toward the contralateral side immediate before the contralateral heel strike in the coronal plane. Conclusions: Men and women showed different lumbar lordosis during normal gait, which might be partly responsible for the different prevalence of lumbar diseases between genders. However, this needs further investigation.

Background: Several 3D multi‐segment foot models (MFMs) have been introduced for the in vivo analysis of dynamic foot kinematics. However, reproducibility of a model should be checked and ascertained before clinical utilization of a MFM. The purpose of this study was to determine the reliability of recently introduced MFM with a 15‐marker set by assessing the participant's stride‐to‐stride (intra‐session) and visit‐to‐revisit (inter‐session) repeatability.Methods: Twenty healthy adults with a mean age of 28.9 years (10 males and 10 females) were tested. Three representative strides from five separate trials were used for analysis from each session. Kinematic data of foot segmental motion was collected and tracked using the Foot3D Multi‐Segment Software (Motion Analysis Co., Santa Rosa. CA). A retest was performed in the same manner at an interval of 4 weeks. Coefficients of multiple correlation (CMC) and intra‐class correlation coefficient (ICC) were calculated in order to assess the intra‐session and inter‐session repeatability.Results: Inter‐segment foot angles from healthy adults from a MFM with 15‐marker set showed a narrow range of variability during the gait cycle. The mean intra‐session ICC was 0.981 (±0.010), which was interpreted as excellent. The mean intra‐session CMC was 0.948 (±0.027), which was interpreted as very good repeatability. The mean inter‐session ICC was 0.886 (±0.047) and the mean inter‐session CMC was 0.801 (±0.077), which were interpreted as excellent and good repeatability, respectively.Conclusion: We demonstrated a MFM with a 15‐marker set had high intra‐session and inter‐session repeatability, especially in sagittal plane motion. We thought this MFM would be applicable to evaluation of the segmental foot motion during gait.

Distraction osteogenesis (DO) is a unique postnatal bone formation process, which is characterized by a profuse increase in vascularization. Recently endothelial progenitor cells (EPCs) have been reported to circulate in substantial numbers under physiologic conditions and to contribute to bone regeneration. The authors investigated EPC mobilization in patients undergoing limb lengthening. Thirteen of 24 consecutive patients who underwent limb-lengthening procedures on weight-bearing long bones (femur and tibia) were included in this study. Peripheral blood samples were taken at four different time points from each patient, that is, before operation (pre-Op), 2 or 3 days after osteotomy (early-PO), before the start of distraction (pre-Dist), and at 7 to 14 days after the start of distraction (during-Dist). Numbers of leukocytes and levels of plasma C-reactive protein (CRP) were determined. After isolating mononuclear cells (MNCs) by centrifugation, we performed FACS analysis on freshly isolated MNCs using antibodies to the cell surface markers; CD34, CD133, vascular endothelial growth factor receptor 2 (VEGFR2), and alkaline phosphatase. MNCs were also cultured in endothelial cell growth medium and numbers of EPC colony-forming units were counted. Plasma levels of EPC-mobilizing cytokines, such as, VEGF, SDF-1, and MCP-1, were determined by ELISA. Numbers of leukocytes and CRP plasma levels increased significantly during the early-PO period (p<0.01) but were maintained within normal range in the during-Dist period. FACS analysis of freshly isolated MNCs showed that EPC-enriched cell fractions increased after distraction, but that alkaline phosphatase-positive cell numbers were unchanged. Numbers of EPC colony-forming units significantly increased in the during-Dist period (p<0.01). Plasma levels of VEGF and SDF-1 significantly increased in the during-Dist period (p<0.05). In femoral lengthening patients whose healing index was less than 30 days/cm, the number of CFUs was 46.8 in the during-Dist period, whereas it was 12.7 in patients whose healing index was more than 30 days/cm (p=0.088). This study demonstrates a mobilization of EPC population during distraction osteogenesis in human limb-lengthening patients. Distraction strain provoked increases in the plasma levels of EPC-mobilizing cytokines, such as, VEGF and SDF-1. These findings suggest a possibility that therapeutical approaches which modulate EPC mobilization may speed bone healing by angiogenesis-osteogenesis coupling during distraction osteogenesis.

Background: The relationship between torsional bony deformities and rotational gait parameters has not been sufficiently investigated. This study was to investigate the degree of contribution of torsional bony deformities to rotational gait parameters in patients with diplegic cerebral palsy (CP). Methods: Thirty three legs from 33 consecutive ambulatory patients (average age 9.5 years, SD 6.9 years; 20 males and 13 females) with diplegic CP who underwent preoperative three dimensional gait analysis, foot radiographs, and computed tomography (CT) were included. Adjusted foot progression angle (FPA) was retrieved from gait analysis by correcting pelvic rotation from conventional FPA, which represented the rotational gait deviation of the lower extremity from the tip of the femoral head to the foot. Correlations between rotational gait parameters (FPA, adjusted FPA, average pelvic rotation, average hip rotation, and average knee rotation) and radiologic measurements (acetabular version, femoral anteversion, knee torsion, tibial torsion, and anteroposteriortalo-first metatarsal angle) were analyzed. Multiple regression analysis was performed to identify significant contributing radiographic measurements to adjusted FPA. Results: Adjusted FPA was significantly correlated with FPA (r=0.837, p<0.001), contralateral FPA (r=0.492, p=0.004), pelvic rotation during gait (r=−0.489, p=0.004), knee rotation during gait (r=0.376, p=0.031), and femoral anteversion (r=0.350, p=0.046). In multiple regression analysis, femoral anteversion (p=0.026) and tibial torsion (p=0.034) were found to be the significant contributing structural deformities to the adjusted FPA (R²=0.247). Conclusions: Femoral anteversion and tibial torsion were found to be the significant structural deformities that could affect adjusted FPA in patients with diplegic CP. Femoral anteversion and tibial torsion could explain only 24.7% of adjusted FPA.

To compare the clinical and radiological features of intra-/juxta-articular osteoid osteoma and extra-articular osteoid osteoma in skeletally immature patients, paying special attention to the skeletal complications. Osteoid osteoma in 34 children (22 boys and 12 girls, mean age 10.4 years) was dichotomized according to the location of the nidus as intra-/juxta-articular (11 children) or extra-articular (23 children). The following features were compared: diagnostic delay, typical symptoms, synovitis and limited range of joint motion, response to treatment, typical radiographic findings, and skeletal complications. Eight of the 11 children with intra-/juxta-articular osteoid osteoma presented with synovitis in the involved joint, which led to a delayed diagnosis for a median 9.5 months. Pain disappeared in all children with surgical or medical interventions, but at the mean 4.9-year follow-up evaluation, skeletal abnormalities around the joint were noted in 5 children (4 proximal femur and 1 distal humerus) with intra-/juxta-articular osteoid osteoma, 2 of whom required subsequent surgeries for limited hip motion caused by femoroacetabular impingement and limited range of elbow motion, respectively. In contrast, typical clinical and radiological features were observed more often in extra-articular osteoid osteoma, and only 1 child showed overgrowth of the tibia, which did not have clinical significance. Intra-/juxta-articular osteoid osteomas in growing children exhibit different clinical and radiological features from extra-articular lesions. Skeletal abnormalities mainly develop in intra-/juxta-articular osteoid osteoma, and these may lead to permanent skeletal sequelae.