Sex-Related Differences in Shoulder Complex Joint Dynamics Variability During Pediatric Manual Wheelchair Propulsion.

More than 80% of adult manual wheelchair users with spinal cord injuries will experience shoulder pain. Females and those with decreased shoulder dynamics variability are more likely to experience pain in adulthood. Sex-related differences in shoulder dynamics variability during pediatric manual wheelchair propulsion may influence the lifetime risk of pain. We evaluated the influence of sex on 3-dimensional shoulder complex joint dynamics variability in 25 (12 females and 13 males) pediatric manual wheelchair users with spinal cord injury. Within-subject variability was quantified using the coefficient of variation. Permutation tests evaluated sex-related differences in variability using an adjusted critical alpha of P = .001. No sex-related differences in sternoclavicular or acromioclavicular joint kinematics or glenohumeral joint dynamics variability were observed (all P ≥ .042). Variability in motion, forces, and moments are considered important components of healthy joint function, as reduced variability may increase the likelihood of repetitive strain injury and pain. While further work is needed to generalize our results to other manual wheelchair user populations across the life span, our findings suggest that sex does not influence joint dynamics variability in pediatric manual wheelchair users with spinal cord injury.

A multicenter study to evaluate pain characteristics in osteogenesis imperfecta.

The objective was to describe pain characteristics and treatments used in individuals with varying severity of osteogenesis imperfecta (OI) and investigate pain-associated variables. This work was derived from a multicenter, longitudinal, observational, natural history study of OI conducted at 12 clinical sites of the NIH Rare Diseases Clinical Research Network's Brittle Bone Disorders Consortium. Children and adults with a clinical, biochemical, or molecular diagnosis of OI were enrolled in the study. We did a cross-sectional analysis of chronic pain prevalence, characteristics, and treatments used for pain relief and longitudinal analysis to find the predictors of chronic pain. We included 861 individuals with OI, in 41.8% chronic pain was present, with similar frequency across OI types. Back pain was the most frequent location. Nonsteroidal anti-inflammatory drugs followed by bisphosphonates were the most common treatment used. Participants with chronic pain missed more days from school or work/year and performed worse in all mobility metrics than participants without chronic pain. The variables more significantly associated with chronic pain were age, sex, positive history of rodding surgery, scoliosis, other medical problems, assistive devices, lower standardized height, and higher body mass index. The predictors of chronic pain for all OI types were age, use of a wheelchair, and the number of fractures/year. Chronic pain is prevalent in OI across all OI types, affects mobility, and interferes with participation. Multiple covariates were associated with chronic pain.

Relationships Among Shoulder Rotational Strength, Range of Motion, Pitching Kinetics, and Pitch Velocity in Collegiate Baseball Pitchers.

ABSTRACT: Cross, JA, Higgins, AW, Dziuk, CC, Harris, GF, and Raasch, WG. Relationships among shoulder rotational strength, range of motion, pitching kinetics, and pitch velocity in collegiate baseball pitchers. J Strength Cond Res 37(1): 129-135, 2023-Throwing shoulder injuries are the most common type of injury experienced by baseball pitchers. Weakness in the shoulder musculature and insufficient throwing arm range of motion are both risk factors for developing a shoulder injury. The goal of this study was to determine correlations among shoulder rotational strength, range of motion, pitching kinetics, and pitch velocity in collegiate pitchers. Thirteen uninjured male college pitchers were evaluated. Clinical measures included shoulder internal and external rotation range of motion, peak isokinetic internal and external rotator strength, and peak isometric internal and external rotator strength. Three-dimensional biomechanics were assessed as subjects threw from an indoor pitching mound to a strike zone net at regulation distance. Pearson's correlations were used to assess the associations among the clinical measures and throwing metrics. Five significant correlations were found between peak shoulder compressive force and strength, and 4 significant correlations were found between pitching velocity and strength ( p < 0.05). No significant correlations were found between range of motion and pitching kinetics or velocity. Our results suggest that as shoulder rotational strength increases, the peak shoulder compressive force and pitch velocity both increase. Knowledge of relationships between strength metrics and pitching biomechanics may allow for improved strength training routines with the goal of increasing velocity without increasing injury risk.

Do Bisphosphonates Alleviate Pain in Children? A Systematic Review.

PURPOSE OF REVIEW: The goal of this systematic review is to analyze the effectiveness of bisphosphonates (BPs) to treat bone pain in children and adolescents who have diseases with skeletal involvement. RECENT FINDINGS: We included 24 studies (2 randomized controlled trials, 3 non-randomized controlled trials, 10 non-randomized open-label uncontrolled studies, 8 retrospective studies, and 1 study with design not specified). The majority of included studies assessed pain from a unidimensional approach, with pain intensity the most frequently evaluated dimension. Only 38% of studies used validated tools; visual analogue scale was the most frequently employed. BPs were used to alleviate bone pain in a wide variety of pediatrics conditions such as osteogenesis imperfecta, secondary osteoporosis, osteonecrosis related to chemotherapy, chronic non-bacterial osteitis, idiopathic juvenile osteoporosis, unresectable benign bone tumor, and cancer-related pain. Twenty of the 24 studies reported a positive effect of BPs for alleviating pain in different pathologies, but 58% of the studies were categorized as having high risk of bias. Intravenous BPs are helpful in alleviating bone pain in children and adolescents. It is advised that our results be interpreted with caution due to the heterogeneity of the doses used, duration of treatments, and types of pathologies included. In addition, this review shows the paucity of high-quality evidence in the available literature and further research is needed. TRIAL REGISTRATION: Before the completion of this review, the protocol was registered to PROSPERO (International prospective register of systematic reviews), PROSPERO 2020 ID # CRD42020158316. Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020158316.

Mobility in osteogenesis imperfecta: a multicenter North American study.

PURPOSE: Osteogenesis imperfecta (OI) is a genetic connective tissue disorder that causes bone fragility. Phenotypic severity influences ability to walk, however, little is known about ambulatory characteristics of individuals with OI, especially in more severe forms. The purpose of this work was to characterize mobility in OI using standard clinical assessment tools and determine if patient characteristics could be used to predict mobility outcomes. METHODS: We collected mobility data at five clinical sites to analyze the largest cohort of individuals with OI (n = 491) to date. Linear mixed models were developed to explore relationships among subject demographics and mobility metrics. RESULTS: Results showed minor limitations in the mild group while the more severe types showed more significant limitations in all mobility metrics analyzed. Height and weight were shown to be the most significant predictors of mobility. Relationships with mobility and bisphosphonates varied with OI type and type used (oral/IV). CONCLUSION: These results are significant to understanding mobility limitations of specific types of OI and beneficial when developing rehabilitation protocols for this population. It is important for physicians, patients, and caregivers to gain insight into severity and classification of the disease and the influence of disease-related characteristics on prognosis for mobility.

A Long-term Follow-up of Young Adults With Idiopathic Clubfoot: Does Foot Morphology Relate to Pain?

BACKGROUND: Individuals with clubfoot, treated in infancy with either the Ponseti method or comprehensive clubfoot release, often encounter pain as adults. Multiple studies have characterized residual deformity after Ponseti or surgical correction using physical exam, radiographs and pedobarography; however, the relationship between residual foot deformity and pain is not well defined. The purpose of the current study was 2-fold: (1) to evaluate the relationship between foot morphology and pain for young adults treated as infants for idiopathic clubfoot and (2) to describe and compare pedobarographic measures and outcome measures of pain and morphology among surgically treated, Ponseti treated, and typically developing feet. METHODS: We performed a case-control study of individuals treated for clubfoot at 2 separate institutions with either the Ponseti method or comprehensive clubfoot release between 1983 and 1987. All subjects (24 treated with comprehensive clubfoot release, 18 with Ponseti method, and 48 controls) were evaluated using the International Clubfoot Study Group (ICFSG) morphology scoring, dynamic pedobarography, and foot function index surveys. During pedobarography, we collected the subarch angle and arch index as well as the center of pressure progression (COPP) on all subjects. RESULTS: Foot morphology (ICFSG) scores were highly correlated with foot function index pain scores (r=0.43; P<0.001), although the difference in pain scores between the surgical and Ponseti group did not reach significance. The surgical group exhibited greater subarch angle and arch indexes than the Ponseti group, demonstrating a significant difference in morphology, a flatter foot. Finally, we found more abnormalities in foot progression, decreased COPP in the forefoot and increased COPP in the midfoot and hindfoot, in the surgical group compared with controls. CONCLUSIONS: Measures of foot morphology were correlated with pain among all treated for clubfoot. Compared with Ponseti method, comprehensive surgical release lead to greater long-term foot deformity, flatter feet and greater hindfoot loading time. LEVEL OF EVIDENCE: Level III-Therapeutic.

Considering Propulsion Pattern in Therapeutic Outcomes for Children Who Use Manual Wheelchairs.

PURPOSE: Children who use manual wheelchairs encounter pain and injury risks to the upper body. Current literature does not describe how propulsion pattern and physiotherapeutic training methodologies impact response to treatment. METHODS: This study assesses the effect of community-based intensive physical and occupational therapy on functional outcomes over a 7-week period in pediatric manual wheelchair users. RESULTS: Key results include significant joint and musculotendon kinematic differences at the shoulder, improved speed and propulsion effectiveness, and changed propulsion pattern. CONCLUSIONS: Statistics also revealed that propulsion pattern was a predictor of response to therapy, as was weekly therapeutic duration, wheelchair-specific focus by the therapists, and stretching.

How a diverse research ecosystem has generated new rehabilitation technologies: Review of NIDILRR's Rehabilitation Engineering Research Centers.

Over 50 million United States citizens (1 in 6 people in the US) have a developmental, acquired, or degenerative disability. The average US citizen can expect to live 20% of his or her life with a disability. Rehabilitation technologies play a major role in improving the quality of life for people with a disability, yet widespread and highly challenging needs remain. Within the US, a major effort aimed at the creation and evaluation of rehabilitation technology has been the Rehabilitation Engineering Research Centers (RERCs) sponsored by the National Institute on Disability, Independent Living, and Rehabilitation Research. As envisioned at their conception by a panel of the National Academy of Science in 1970, these centers were intended to take a "total approach to rehabilitation", combining medicine, engineering, and related science, to improve the quality of life of individuals with a disability. Here, we review the scope, achievements, and ongoing projects of an unbiased sample of 19 currently active or recently terminated RERCs. Specifically, for each center, we briefly explain the needs it targets, summarize key historical advances, identify emerging innovations, and consider future directions. Our assessment from this review is that the RERC program indeed involves a multidisciplinary approach, with 36 professional fields involved, although 70% of research and development staff are in engineering fields, 23% in clinical fields, and only 7% in basic science fields; significantly, 11% of the professional staff have a disability related to their research. We observe that the RERC program has substantially diversified the scope of its work since the 1970's, addressing more types of disabilities using more technologies, and, in particular, often now focusing on information technologies. RERC work also now often views users as integrated into an interdependent society through technologies that both people with and without disabilities co-use (such as the internet, wireless communication, and architecture). In addition, RERC research has evolved to view users as able at improving outcomes through learning, exercise, and plasticity (rather than being static), which can be optimally timed. We provide examples of rehabilitation technology innovation produced by the RERCs that illustrate this increasingly diversifying scope and evolving perspective. We conclude by discussing growth opportunities and possible future directions of the RERC program.

Sagittal Fluoroscopy for the Assessment of Hindfoot Kinematics.

Current methods of quantifying foot kinematics during gait typically use markers placed externally on bony anatomic locations. These models are unable to analyze talocrural or subtalar motion because the talus lacks palpable landmarks to place external markers. Alternative methods of measuring these clinically relevant joint motions are invasive and have been limited to research purposes only. This study explores the use of fluoroscopy to noninvasively quantify talocrural and subtalar sagittal plane kinematics. A fluoroscopy system (FS) was designed and built to synchronize with an existing motion analysis system (MAS). Simultaneous fluoroscopic, marker motion, and ground reaction force (GRF) data were collected for five subjects to demonstrate system application. A hindfoot sagittal plane model was developed to evaluate talocrural and subtalar joint motion. Maximum talocrural plantar and dorsiflexion angles averaged among all the subjects occur at 12% and 83% of stance, respectively, with a range of motion of 20.1 deg. Maximum talocrural plantar and dorsiflexion angles averaged among all the subjects occur at toe-off and 67% of stance, respectively, with a range of motion of 8.7 deg. Based on the favorable comparison between the current fluoroscopically measured kinematics and previously reported results from alternative methods, it is concluded that fluoroscopic technology is well suited for measuring the sagittal plane hindfoot motion.

A bidirectional model of postural sway using force plate data.

This work was designed to expand on our previous anterior-posterior postural control model to include medial-lateral sway of unperturbed posture during quiet standing. The bidirectional model simulates two decoupled inverted pendulums, each restricted to sway in either the anterior-posterior (AP) direction (ankle strategy) or medial-lateral (ML) direction (hip strategy), and each controlled by a Proportional-Integral-Derivative (PID) controller. Postural data was collected from 31 healthy participants under different sensory test conditions: eyes closed, eyes open, and eyes open with real-time visual feedback. Simulation iterations of the bidirectional model were run for each sensory test condition to adjust the PID controller parameters until modeled sway metrics did not differ significantly from experimental metrics at p ≤ 0.01. Simulations did not show significant changes in the AP sway controller parameters among the 3 sensory test conditions. The model did show significant changes in ML sway controller parameters, namely stiffness and time delay. Significant differences were also seen in the experimental sway metrics under the three different sensory test conditions. The multi-sensory evaluation and bidirectional sway model offer unique insight for further exploration of postural pathology, control mechanisms and planar coupling that includes both ankle and hip strategies.

Long-term results of comprehensive clubfoot release versus the Ponseti method: which is better?

BACKGROUND: Clubfoot can be treated nonoperatively, most commonly using a Ponseti approach, or surgically, most often with a comprehensive clubfoot release. Little is known about how these approaches compare with one another at longer term, or how patients treated with these approaches differ in terms of foot function, foot biomechanics, or quality-of-life from individuals who did not have clubfoot as a child. QUESTIONS/PURPOSES: We compared (1) focused physical and radiographic examinations, (2) gait analysis, and (3) quality-of-life measures at long-term followup between groups of adult patients with clubfoot treated either with the Ponseti method of nonsurgical management or a comprehensive surgical release through a Cincinnati incision, and compared these two groups with a control group without clubfoot. METHODS: This was a case control study of individuals treated for clubfoot at two separate institutions with different methods of treatment between 1983 to 1987. One hospital used only the Ponseti method and the other mainly used a comprehensive clubfoot release. There were 42 adults (24 treated surgically, 18 treated with Ponseti method) with isolated clubfoot along with 48 healthy control subjects who agreed to participate in a detailed analysis of physical function, foot biomechanics, and quality-of-life metrics. RESULTS: Both treatment groups had diminished strength and motion compared with the control subjects on physical examination measures; however, the Ponseti group had significantly greater ankle plantar flexion ROM (p < 0.001), greater ankle plantar flexor (p = 0.031) and evertor (p = 0.012) strength, and a decreased incidence of osteoarthritis in the ankle and foot compared with the surgical group. During gait the surgical group had reduced peak ankle plantar flexion (p = 0.002), and reduced sagittal plane hindfoot (p = 0.009) and forefoot (p = 0.008) ROM during the preswing phase compared with the Ponseti group. The surgical group had the lowest overall ankle power generation during push off compared with the control subjects (p = 0.002). Outcome tools revealed elevated pain levels in the surgical group compared with the Ponseti group (p = 0.008) and lower scores for physical function and quality-of-life for both clubfoot groups compared with age-range matched control subjects (p = 0.01). CONCLUSIONS: Although individuals in each treatment group experienced pain, weakness, and reduced ROM, they were highly functional into early adulthood. As adults the Ponseti group fared better than the surgically treated group because of advantages including increased ROM observed at the physical examination and during gait, greater strength, and less arthritis. This study supports efforts to correct clubfoot with Ponseti casting and minimizing surgery to the joints, and highlights the need to improve methods that promote ROM and strength which are important for adult function. LEVEL OF EVIDENCE: Level III, prognostic study.

Multisegmental foot and ankle motion analysis after hallux valgus surgery.

BACKGROUND: Gait changes in patients with hallux valgus, including altered kinematic and temporal-spatial parameters, have been documented in the literature. Although operative treatment can yield favorable clinical and radiographic results, restoration of normal gait in this population remains unclear. Segmental kinematic changes within the foot and ankle during ambulation after operative correction of hallux valgus have not been reported. The aim of this study was to analyze changes in multisegmental foot and ankle kinematics in patients who underwent operative correction of hallux valgus. METHODS: A 15-camera Vicon Motion Analysis System was used to evaluate 24 feet in 19 patients with hallux valgus preoperatively and postoperatively. The Milwaukee Foot Model was used to characterize segmental kinematics and temporal-spatial parameters (TSPs). Preoperative and postoperative kinematics and TSPs were compared using paired nonparametric methods; comparisons with normative data were performed using unpaired nonparametric methods. Outcomes were evaluated using the SF-36 assessment tool. RESULTS: Preoperatively, patients with hallux valgus showed significantly altered temporal-spatial and kinematic parameters. Postoperatively, kinematic analysis demonstrated restoration of hallux position to normal. Hallux valgus angles and intermetatarsal angles were significantly improved, and outcomes showed a significant increase in performance of physical activities. Temporal-spatial parameters and kinematics in the more proximal segments were not significantly changed postoperatively. CONCLUSION: Postoperative results demonstrated significant improvement in foot geometry and hallux kinematics in the coronal and transverse planes. However, the analysis did not identify restoration of proximal kinematics. CLINICAL RELEVANCE: Further investigation is necessary to explore possible causes/clinical relevance and appropriate treatment interventions for the persistently altered kinematics.

The Influence of Age at Pediatric-Onset Spinal Cord Injury and Years of Wheelchair Use on Shoulder Complex Joint Dynamics During Manual Wheelchair Propulsion.

Objective: To assess the association of age at pediatric-onset spinal cord injury (SCI) and years of manual wheelchair use with shoulder dynamics. Design: Upper extremity kinematics and hand-rim kinetics were obtained during manual wheelchair propulsion. An inverse dynamics model computed three-dimensional acromioclavicular, sternoclavicular, and glenohumeral joint dynamics. Linear mixed effects models evaluated the association of age at injury onset and years of wheelchair use with shoulder dynamics. Setting: Motion laboratory within a children's hospital. Participants: Seventeen manual wheelchair users (N=17; 6 female, 11 male; mean age: 17.2 years, mean age at SCI onset: 11.5 years) with pediatric-onset SCI (levels: C4-T11) and International Standards for Neurological Classification of SCI grades: A (11), B (3), C (2), and N/A (2). Interventions: Not applicable. Main Outcome Measures: Acromioclavicular, sternoclavicular, and glenohumeral angles and ranges of motion, and glenohumeral forces and moments. Results: We observed a decrease in maximum acromioclavicular upward rotation (ß [95% confidence interval {CI}]=3.02 [0.15,5.89], P=.039) and an increase in acromioclavicular downward/upward rotation range of motion (ß [95% CI]=0.44 [0.08,0.80], P=.016) with increasing age at SCI onset. We found interactions between age at onset and years of use for maximum glenohumeral abduction (ß [95% CI]=0.16 [0.03,0.29], P=.017), acromioclavicular downward/upward rotation range of motion (ß [95% CI]=-0.05 [-0.09,-0.01], P=.008), minimum acromioclavicular upward rotation (ß [95% CI]=-0.34 [-0.64,-0.04], P=.026). A decrease in glenohumeral internal rotation moment (ß [95% CI]=-0.09 [-0.17,-0.009], P=.029) with increasing years of use was found. Conclusions: Age at injury and the years of wheelchair use are associated with shoulder complex biomechanics during wheelchair propulsion. These results are noteworthy, as both age at SCI onset and years of wheelchair use are considered important factors in the incidence of shoulder pain. These results suggest that investigations of biomechanical changes over the lifespan are critical.

Multi-segment foot kinematics during gait following ankle arthroplasty.

Ankle arthritis is a debilitating disease marked by pain and limited function. Total ankle arthroplasty improves pain while preserving motion and offers an alternative to the traditional treatment of ankle fusion. Gait analysis and functional outcomes tools can provide an objective balanced analysis of ankle replacement for the treatment of ankle arthritis. Twenty-nine patients with end-stage ankle arthritis were evaluated before and after ankle arthroplasty. Multi-segment foot and ankle kinematics were assessed annually following surgery (average 3.5 years, range 1-6 years) using the Milwaukee Foot Model and a Vicon video motion analysis system. Functional outcomes (American Orthopedic Foot and Ankle Society [AOFAS] ankle/hindfoot scale, short form 36 [SF-36] questionnaire) and temporal-spatial parameters were also assessed. Kinematic results were compared to findings from a previously collected group of healthy ambulators. AOFAS and SF-36 mean scores improved postoperatively. Walking speed and stride length increased after surgery. There were significant improvements in tibial sagittal range of motion in terminal stance and hindfoot sagittal range of motion in preswing. Decreased external rotation of the tibia and increased external rotation of the hindfoot were noted throughout the gait cycle. Pain and function improved after ankle replacement as supported by better outcomes scores, increased temporal-spatial parameters, and significant improvement in tibial sagittal range of motion during terminal stance and hindfoot sagittal range of motion during preswing. While multi-segment foot kinematics were improved, they were not restored to control values. Statement of clinical significance: Total ankle arthroplasty does not fully normalize mutli-segment gait kinematics despite improved patient-reported outcomes and gait mechanics.

Biological Sex-Related Differences in Glenohumeral Dynamics Variability during Pediatric Manual Wheelchair Propulsion.

Shoulder pain and pathology are extremely common in adult manual wheelchair users with spinal cord injury (SCI). Within this population, biological sex and variability in shoulder joint dynamics have been shown to be important contributors to both shoulder pain and pathology. Sex-related differences in shoulder dynamics variability during pediatric manual wheelchair propulsion may influence a user's lifetime risk of shoulder pain and pathology. The purpose of this study was to assess the influence of biological sex on variability in three-dimensional (3-D) glenohumeral joint dynamics in pediatric manual wheelchair users with SCI. An inverse dynamics model computed 3-D glenohumeral joint angles, forces, and moments of 20 pediatric manual wheelchair users. Levene's tests assessed biological sex-related differences in variability. Females exhibited less variability in glenohumeral joint kinematics and forces, but greater variability in joint moments than males. Evaluation of glenohumeral joint dynamics with consideration for biological sex and variability strengthens our interpretation of the relationships among shoulder function, pain, and pathology in pediatric manual wheelchair users.Clinical Relevance- Female pediatric manual wheelchair users may be at an increased risk of shoulder repetitive strain injuries due to decreased glenohumeral joint motion and force variability during propulsion. This work establishes quantitative methods for determining the effects of biological sex on the variability of shoulder joint dynamics.

The Influence of Sex on Upper Extremity Joint Dynamics in Pediatric Manual Wheelchair Users With Spinal Cord Injury.

INTRODUCTION: Manual wheelchair propulsion is a physically demanding task associated with upper extremity pain and pathology. Shoulder pain is reported in over 25% of pediatric manual wheelchairs users, and this number rises over the lifespan. Upper extremity biomechanics in adults has been associated with shoulder pain and pathology; however, few studies have investigated upper extremity joint dynamics in children. Furthermore, sex may be a critical factor that is currently unexplored with regard to pediatric wheelchair mobility. OBJECTIVES: To investigate differences in upper extremity joint dynamics between pediatric male and female manual wheelchair users with spinal cord injury (SCI) during wheelchair propulsion. METHODS: Novel instrumented wheelchair hand-rims synchronized with optical motion capture were used to acquire upper extremity joint dynamics of 20 pediatric manual wheelchair users with SCI (11 males, 9 females). Thorax, sternoclavicular, acromioclavicular, glenohumeral, elbow, and wrist joint kinematics and kinetics were calculated during wheelchair propulsion. Linear mixed models were used to assess differences between sexes. RESULTS: Females exhibited significantly greater peak forearm pronation (p = .007), normalized wrist lateral force (p = .03), and normalized elbow posterior force (p = .04) than males. Males exhibited significantly greater peak sternoclavicular joint retraction (p < .001) than females. No significant differences between males and females were observed for the glenohumeral joint (p > .012). CONCLUSION: This study found significant differences in upper extremity joint dynamics between sexes during manual wheelchair propulsion. Our results underscore the importance of considering sex when evaluating pediatric wheelchair mobility and developing comprehensive wheelchair training interventions for early detection and prevention of upper extremity pain and pathology.

Motion of the multisegmental foot in hallux valgus.

BACKGROUND: Hallux valgus is a common condition characterized by lateral deviation of the large toe and medial deviation of the first metatarsal. While some gait analyses of patients with hallux valgus have been performed using plantar pressures, very little is known about the kinematics of gait in this population. The purpose of this study was to evaluate triplanar kinematics in patients with hallux valgus using a multisegmental foot model. MATERIALS AND METHODS: A 15-camera Vicon Motion Analysis System was used to evaluate the gait of 38 feet in 33 patients with mild to severe hallux valgus. The Milwaukee foot model was used to characterize dynamic foot and ankle kinematics and temporal-spatial parameters. Values were compared with normal subjects. Outcomes were evaluated using the SF-36 assessment tool. RESULTS: Patients with hallux valgus showed significantly decreased velocity and stride length and prolonged stance. Significant alterations in gait kinematics were observed in various planes in all segments (hallux, forefoot, hindfoot, and tibia) of the foot and ankle, particularly in the ranges of motion of the hallux and the forefoot. CONCLUSION: The results demonstrate significantly altered kinematic and temporal-spatial parameters reflective of reduced ambulatory function in patients with hallux valgus. As reports describing multisegmental foot and ankle kinematics in this population are limited, this study is valuable in characterizing gait in patients with hallux valgus. CLINICAL RELEVANCE: A better understanding of altered gait dynamics of the multisegmental foot in patients with hallux valgus provides valuable insight on how distal pathology affects proximal segments.

A Multicenter Study of Intramedullary Rodding in Osteogenesis Imperfecta.

BACKGROUND: Osteogenesis imperfecta (OI), a heritable connective tissue disorder with wide clinical variability, predisposes to recurrent fractures and bone deformity. Management requires a multidisciplinary approach in which intramedullary rodding plays an important role, especially for moderate and severe forms. We investigated the patterns of surgical procedures in OI in order to establish the benefits of rodding. The main hypothesis that guided this study was that rodded participants with moderate and severe OI would have lower fracture rates and better mobility. METHODS: With data from the Linked Clinical Research Centers, we analyzed rodding status in 558 individuals. Mobility and fracture data in OI Types III and IV were compared between rodded and non-rodded groups. Univariate regression analyses were used to test the association of mobility outcomes with various covariates pertinent to rodding. RESULTS: Of the individuals with OI, 42.1% had undergone rodding (10.7% of those with Type I, 66.4% with Type III, and 67.3% with Type IV). Rodding was performed more frequently and at a younger age in femora compared with tibiae. Expanding intramedullary rods were used more frequently in femora. In Type III, the rate of fractures per year was significantly lower (p ≤ 0.05) for rodded bones. In Type III, the mean scores on the Gillette Functional Assessment Questionnaire (GFAQ) and Brief Assessment of Motor Function (BAMF) were higher in the rodded group. However, Type-IV non-rodded subjects had higher mean scores in nearly all mobility outcomes. OI type, the use of expanding rods in tibiae, and anthropometric measurements were associated with mobility outcomes scores. CONCLUSIONS: Current practice in 5 orthopaedic centers with extensive experience treating OI demonstrates that most individuals with moderate and severe types of OI undergo rodding procedures. Individuals with severe OI have improved mobility outcomes and lower fracture rates compared with their non-rodded peers, which suggests that early bilateral rodding benefits OI Type III. Our analysis showed a change in practice patterns in the final years of the study in the severe forms, with earlier and more simultaneous rodding procedures performed. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Surgical reconstruction of posterior tibial tendon dysfunction: prospective comparison of flexor digitorum longus substitution combined with lateral column lengthening or medial displacement calcaneal osteotomy.

Posterior tibial tendon dysfunction (PTTD) may require surgical intervention when nonoperative measures fail. Different methods of bony reconstruction may supplement tendon substitution. This study compares two types of bony procedures used to reinforce reconstruction of the posterior tibial tendon-the lateral column lengthening (LCL), and the medial displacement calcaneal osteotomy (MDCO). Twenty patients with PTTD were evaluated before and after scheduled reconstruction comprised of either flexor digitorum longus (FDL) substitution combined with MDCO (MDCO group, 14 patients) or FDL substitution with LCL fusion or osteotomy (LCL group, 6 patients). Foot/ankle kinematics and temporal-spatial parameters were analyzed using the Milwaukee Foot Model, and results were compared to a previously evaluated normal population of 25 patients. Post-operatively, both patient groups demonstrated significantly improved stride length, cadence and walking speed, as well as improved hindfoot and forefoot position in the sagittal plane. The LCL group also demonstrated greater heel inversion. All post-operative subjects revealed significant improvement in the talo-MT1 angle in the A/P and lateral planes, calcaneal pitch and medial cuneiform-MT5 height. Surgical reconstruction of PTTD with either the LCL or MDCO shows comparable improvements in gait parameters, with better heel inversion seen with the LCL, but improved 1st ray plantarflexion and varus with the MDCO. Both procedures demonstrated comparable improvements in radiographic measurements.