Immediate Weight-bearing Through Walker or Crutches After Surgical Fixation of Clavicle Fractures in Patients With Lower Extremity Fractures: A Retrospective Cohort Study.

OBJECTIVES: To assess the safety of immediate upper extremity weight-bearing as tolerated (WBAT) rehabilitation protocol after clavicle fracture open reduction internal fixation (ORIF). DESIGN: Retrospective cohort study. SETTING: Three Level 1 trauma centers. PATIENTS SELECTION CRITERIA: Patients older than 18 years who had ORIF of mid-shaft clavicle fractures and lower extremity fractures who were allowed immediate WBAT on their affected upper extremity through use of a walker or crutches were included. All clavicles were fixed with either precontoured clavicular plates or locking compression plates. Included patients were those who had clinical/radiographic follow-up until fracture union, nonunion, or construct failure. OUTCOME MEASURES AND COMPARISONS: WBAT patients were matched in a one-to-one fashion to a cohort with isolated clavicle fractures who were treated non-weight-bearing (NWB) postoperatively on their affected upper extremity. Matching was done based on age, sex, and temporality of fixation. After matching, treatment and control groups were compared to determine differences in possible confounding variables that could influence the primary outcome, including patient demographics, fracture classification, cortices of fixation, and construct type. All patients were assessed to verify conformity with weight-bearing recommendation. Primary outcome was early hardware failure (HWF) with or without revision surgery. Secondary outcomes included postoperative infections and union of fracture. RESULTS: Thirty-nine patients were included in the WBAT cohort; there were no significant differences with the matched NWB cohort based on patient demographics. Both the WBAT and the NWB cohorts had 2.5% chance of acute HWF that required surgical intervention ( P = 1.0). Additionally, there was no difference in overall HWF ( P = 0.49). All patients despite weight-bearing status including those who required revision ORIF for acute HWF had union of their fracture ( P = 1.0). CONCLUSIONS: Our data would support that immediate weight-bearing after clavicle fracture fixation in patients with concomitant lower extremity trauma does not lead to an increase in HWF or impact ultimate union. This challenges the dogma of prolonged postoperative weight-bearing restrictions and allow for earlier rehabilitation. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Lower Extremity Assistive Devices (LEADs): A Contemporary Literature Review.

Lower extremity ambulatory assistive devices (LEADs) are important augments that provide mobility and stability when weightbearing is restricted in the setting of injury, surgery, or balance disorders. In order to optimize patient safety and function when prescribing these devices, it is essential for the orthopaedic surgeon to have a firm understanding of their specific indications, proper fitting, energy demand, biomechanical advantages, and potential complications. Comprehension of normal gait cadence, identification of the functional deficit present and knowledge of available options will assist in safely prescribing the proper device. Over the last decade, newer alternatives to traditional LEADs (canes, crutches, walkers) have become available, including the rolling knee scooter and hands-free single crutch. These have been developed to improve mobility and independence; however, it is necessary to appreciate their limitations when prescribing them to patients. This review will provide an update on normal and pathologic gait biomechanics as well as the most common types of LEADs currently available to the orthopaedic surgeon, their indications, important considerations, proper fitting, associated energy expenditure, and complications.

Effect of crutch and walking-boot use on whole-body angular momentum during gait.

Crutches are the most prescribed ambulatory assistive device and are used for mobility and maintaining weight-bearing restrictions after injury or surgery. However, standard axillary crutches (SACs) can lead to overuse and other injuries and restrict upper limb movement. Hands-free crutches (HFC) do not restrict upper limb movement but their effect on balance control, with or without commonly prescribed walking boots, is poorly understood. The purpose of this study was to compare the effect of crutch type (SACs vs. HFC) and boot use on whole-body angular momentum (RAM), a measure of balance control. Participant's balance confidence, pain, comfort, and device preference were assessed. Seventeen participants were evaluated while walking without a crutch (NONE), with SACs, and with an HFC, and walked with and without a walking boot in each crutch condition. The gait pattern used with SACs resulted in significantly greater limb angular velocity (p < .05), and an 84% increase in RAM (p < .001) as compared to the HFC. There were no differences between the SAC and HFC for balance confidence, pain, or comfort, however most (71.1%) participants preferred the HFCs. These results suggest that individuals can better control angular momentum with the HFCs and thus may be less susceptible to loss of balance.

Exploiting Natural Locomotion Synergies to Incorporate Motion of Crutches for Adaptive Gait Pattern Shaping.

This paper addresses the problem of online and adaptive gait pattern generation for powered lower-limb exoskeletons (PLLEs), exploiting the motion of sensorized crutches. We conduct a series of experiments with subjects walking with and without crutches to investigate the synergies of walking between upper and lower body segments, by adopting principal component analysis (PCA), We also evaluate the effect of using crutches on the walking synergies, and we demonstrate that upper and lower limb walking synergies undergo slight changes in that case. However, the upper and lower limb synergies remain evident and can be exploited in order to use the motion of crutches as an input to PLLEs to identify a desired motion of the lower limb. We propose a method to use the results of synergy analysis to shape gait parameters in the real-time control of PLLEs. To evaluate the scalability of our approach for real-world applications, we conduct a number of experiments with subjects wearing a PLLE and using sensorized crutches to adaptively change the gait parameters of walking steps, depending on upper body actions.

Comparative Analysis of Predetermined Axillary Crutch Length Settings to Individualized Fittings.

Axillary crutches are the most common assistive devices given to individuals with musculoskeletal injuries in an acute care setting. Nurses are frequently the care provider fitting injured individuals with crutches. This study compared the crutch length determined by the crutch manufacturer's height setting with the crutch length attained after applying a standard clinical protocol for crutch fitting. A total of 116 adults with lower extremity injuries were enrolled. Self-reported height was documented as well as initial crutch length as indicated by the numbers on the push-button feature of the crutches. Subject height with and without shoes was measured. Proper crutch length was then determined using the method described by Bauer et al. (1991). No change between the initial and adjusted crutch settings was made in 43% of the subjects. Change was made in 57% of the subjects: lengthening in 40% and shortening in 17% of subjects. This study revealed the predetermined crutch settings are unreliable and should simply be used as a starting point during a personalized fitting.

Validation of Estimators for Weight-Bearing and Shoulder Joint Loads Using Instrumented Crutches.

This research paper aimed to validate two methods for measuring loads during walking with instrumented crutches: one method to estimate partial weight-bearing on the lower limbs and another to estimate shoulder joint reactions. Currently, gait laboratories, instrumented with high-end measurement systems, are used to extract kinematic and kinetic data, but such facilities are expensive and not accessible to all patients. The proposed method uses instrumented crutches to measure ground reaction forces and does not require any motion capture devices or force platforms. The load on the lower limbs is estimated by subtracting the forces measured by the crutches from the subject's total weight. Since the model does not consider inertia contribution in dynamic conditions, the estimation improves with low walking cadence when walking with the two-point contralateral and the three-point partial weight-bearing patterns considered for the validation tests. The shoulder joint reactions are estimated using linear regression, providing accurate values for the forces but less accurate torque estimates. The crutches data are acquired and processed in real-time, allowing for immediate feedback, and the system can be used outdoors in real-world walking conditions. The validation of this method could lead to better monitoring of partial weight-bearing and shoulder joint reactions, which could improve patient outcomes and reduce complications.

Load analysis of hands and feet while using different types of crutches with various leg's weight bearing.

The study aimed to define the load on hands using various commonly used types of crutches while walking with a full load on both legs (FL), with 20 kg partial load (PL), or with the left leg wholly unloaded (UL). Twenty-six healthy subjects used crutches with ergonomic handles, with anatomic handles (wider and softer bearing surface), and arthritis crutches (horizontal supporting area for the forearm). Sensor mats between hand and handles continuously measured the load transmitted, while sensor soles in the shoes recorded the ground reaction forces simultaneously. The load on the palm and separately the radial and ulnar halves of the palm were analyzed. With arthritis crutches, significantly lower load was transferred to the hands compared to forearm crutches (FL 3% vs. 25% of body weight, PL 8% vs. 87%, UL 12% vs. 103%). The load on hands increased significantly from FL to PL and UL for both types of crutches. The ipsilateral left hand had to bear significantly more load than the right hand. However, the feet's time-ground reaction curves showed more irregularities, and PL on the left leg was significantly higher with arthritis crutches. Anatomic handles reduced the load on the ulnar half of the palm (FL 3% vs. 5%, PL 13% vs. 18%, UL 17% vs. 23%); the radial half of the palm had a similar load to bear with both types of handles (11/11%, 31/32%, 34/35%). Arthritis crutches allow unburdening hands at the expense of gait stability. Anatomic handles reduce the load on the Guyon's canal.

A comparison of elbow and wrist kinematics and kinetics during swing-through versus reciprocal gait with crutches in persons with incomplete spinal cord injury.

STUDY DESIGN: Descriptive study with cross-sectional data collection. OBJECTIVES: To analyse and compare the 3D kinematics and kinetics of thorax, elbow and wrist, and the spatio-temporal parameters during swing-through gait (SG) and reciprocal gait (RG). SETTING: Hospital Nacional de Parapléjicos in Toledo, Spain. METHODS: An instrumented biomechanical analysis of the upper body of 15 adults with an incomplete lumbar or thoracic spinal cord injury was performed using a marker motion capture system and load cell crutches. Five walks of each gait pattern were analysed. RESULTS: The elbow was in flexion, valgus and pronation and the wrist was in extension and ulnar deviation in both SG and RG. Their kinematic patterns were quite similar, except in elbow valgus and wrist extension in which statistically significant differences were observed. In the thorax prevailed flexion movement in SG and rotation movement in RG. The reaction forces in the elbow and the wrist were notably higher in SG than in RG, but the joint moments were similar in both gait patterns. CONCLUSIONS: SG showed greater demands and RG showed higher requirements on trunk motor control. In addition, SG could increase the probability of back and neck pain. Therefore RG should be recommended, whenever possible, in incomplete spinal cord injured people. Rehabilitative management should consider adapting properly the crutch height and the inclination cane, loading the minimum weight on the crutches, using cushioning devices, reducing the duration of support phase, and limiting the overall use time of the crutches.

Art and Pediatric Orthopaedics: Cot and the Crutch.

Pierre Auguste Cot's painting, "Mireille giving alms at the door of Saint-Trophime," depicts a wealthy lady giving alms to a crippled beggar boy. The beautiful painting portrays the striking contrast between the rich and the poor. The painting also draws attention to the crude crutch the boy was using. This type of crutch was used over the centuries; improvements in the design of the axillary crutch occurred only in the 20th century.

The effect of axillary crutch length on upper limb kinematics during swing-through gait.

BACKGROUND: Axillary crutches are commonly used in rehabilitation. Inappropriately fit crutches may result in upper limb pain or injury. OBJECTIVE: To investigate the effects of axillary crutch length on upper limb kinematics to better understand potential injury mechanisms. It was hypothesized that crutches that were longer or shorter than standard-fit crutches would alter upper limb kinematics. DESIGN: Cross-sectional. SETTING: Gait laboratory. PARTICIPANTS: Fifteen healthy males with no prior crutch experience. INTERVENTIONS: Participants were fit with axillary crutches using standardized methods, as well as with crutches that were 5 cm longer and 5 cm shorter. Participants performed swing-through gait (1.20 ± 0.07 ms-1 ) with all crutch lengths in randomized order. Kinematics were recorded using an optical motion-tracking system and joint angles for the scapula, shoulder, elbow, and wrist were computed. MAIN OUTCOME MEASURES: The effects of crutch length on joint range of motion (ROM) and joint angles at initial crutch contact were analyzed using multivariate analysis (Hotelling's T2 ; α = .025) and simultaneous confidence intervals (CI). RESULTS: The long-standard crutch fit comparison showed effects across all joints (ROM p = .009; initial contact p < .001). Longer crutches resulted in greater scapular upward rotation (mean difference [95% CI] ROM: 1.0 [-0.2 to 2.2]; initial contact: -2.7 [-4.4, -1.1]) and shoulder abduction (ROM: 0.8 [-0.1 to 1.8]; initial contact: -1.9 [-4.1 to 0.3]). Crutch length also had effects across all joints for the short-standard fit comparison (ROM p = .004; initial contact p = .016). Shorter crutches resulted in greater scapula downward rotation (2.2 [-0.4 to 4.8]) and greater shoulder adduction (2.5 [-0.6 to 5.6]) at initial contact. Shorter crutches also reduced shoulder flexion/extension ROM (-2.5 [-4.4 to -0.6]). CONCLUSIONS: Altered crutch length results in scapular and shoulder kinematic deviations that may present risk factors for upper limb injury with crutch-walking. This may underline the importance of appropriate device fitting to reduce injury risk in crutch users.

Identification of gait patterns in walking with crutches through the selection of significant spatio-temporal parameters.

Forearm crutches are one of the most accepted aids in rehabilitation for walking. The improper use of crutches may prolong the rehabilitation period and cause further limb damage or pain. However, it is possible to tackle this issue by using instrumented crutches that provide a quantitative gait analysis of the users. In addition, the study of different aspects of crutch walking could assist clinicians in choosing the optimum crutch gait pattern for individuals and instruct them to use the aids correctly. Measurements from the crutches are influenced by the performed gait pattern, determined by the legs and arms' sequence of movement. Since different parameters can describe gait, this paper aims to identify four gait patterns in walking with crutches through a reliable selection of gait parameters. In this study, we collected data from twenty healthy volunteers performing four gait patterns to reach this goal. First, we segmented the gait sequence in periodic cycles to detect two main phases, swing and stance. Then, we calculated different parameters for each gait walking pattern. Subsequently, we found a reduced set of parameters through some feature selection techniques. Selected parameters were validated employing three classification models. After evaluating the models' metrics, our findings indicated that the set of selected parameters could identify a crutch walking pattern.

Exploring the Utility of Crutch Force Sensors to Predict User Intent in Assistive Lower Limb Exoskeletons.

The adoption of assistive lower limb exoskeletons in built environments is reliant on the further development of these devices to handle the varied conditions experienced in everyday life. The required development includes more varied and flexible gait patterns, but also appropriate user interfaces to enable fluid gait. This work explores the properties of an algorithm used to predict user intent based on sensors onboard a user-balanced robotic exoskeleton system. Specifically, classification algorithms built with different input data sets are compared - with varying detail of the interaction forces between the crutches and the ground, and the duration of the data sample used to make the prediction. Data were collected with one able-bodied participant using an exoskeleton, training three independent classifiers corresponding to different exoskeleton states. The results indicate the value of including information about the interaction forces between the crutches and the ground in improving prediction accuracy, with increasing prediction window also generally resulting in an increase in prediction accuracy. Whilst no categorical recommendation can be made with respect to either parameter, these results provide a baseline which can be used in conjunction deliberate consideration of the costs associated with implementation.

The effect of limited sensory information on exoskeleton performance in people with complete spinal cord injury.

Despite the absence of somatosensory information from the lower extremities, people with complete spinal cord injury (SCI) can maintain postural stability in an exoskeleton. This is partly because humans are able to reweigh the relative dependence on each of the senses. However, when the sensory environment is changed, people with complete SCI are limited in their ability to reweigh their sensory organization towards more dependence on somatosensory information. The aim of this study was to investigate the effect of limited visual and/or auditory information on exoskeleton performance in people with complete SCI. Three experienced exoskeleton users performed twelve walking trials in the ReWalk exoskeleton. In each trial, the presence or absence of visual and/or auditory information was varied. Exoskeleton performance was operationalized as the walking distance covered and the amount of crutch loading. In one participant, the distance covered decreased when visual information was limited. The other two participants did not show substantial differences in distance covered between sensory conditions. Two participants decreased crutch loading when visual information was restricted, and one participant decreased crutch loading when auditory information was limited. The current study suggests a limited influence of the presence or absence of visual and auditory information on the distance covered in people with complete SCI walking in an exoskeleton. Interestingly, crutch loading seemed to decrease rather than increase when visual or auditory information was limited.

A Unified Gait Phase Estimation and Control of Exoskeleton using Virtual Energy Regulator (VER).

Virtual Energy Regulator (VER) is a time independent controller that can generate stable limit cycles in lower-limb exoskeleton devices. In this work, we apply VER to control a lower-limb exoskeleton for assistive walking. We design two different limit cycles for hip and knee joints to assist the user during overground walking with the Indego explorer lower-limb exoskeleton. We tested the designed VER on a single participant for overground walking at a self-selected speed. Interestingly, due to VER time-independent nature, it can properly coordinate with the user's motions and produce mechanically stable overground walking in which the user can walk overground without a walker or crutches. The resultant gait is also more similar to a normal gait with improved range of motion compared to cases without controller; range of motion improved from $42.9 \pm 4.8{deg}$ and $44.9 \pm 4.9 {deg}$ to $46.6 \pm 1.3 {deg}$ and $63.0 \pm 6.8 {deg}$ at hip and knee joints, respectively. Especially, for the knee joint, the user is able to fully extend her knee during stance phase only when the VER is in the loop. In VER, the radius of each desired limit cycle is a function of phase. Accordingly, during walking, the internal phase of the VER is a monotonically increasing parameter that can be considered as a candidate for real-time gait phase estimation and heel-strike event detection. Hence, for gait phase estimation, VER relies only on a single joint position provided by the exoskeleton.

Fourteen Crutches for Mediocrity. The logismoi that jeopardize good research and publication.

Publications are used widely as a measure of academic quality. Many investigators have difficulty publishing in this competitive field. After coming across a religious lecture on the "Fourteen Crutches for Mediocrity", our team adapted this approach to life to the science of publishing: (1) what is the problem of doing it?; (2) there are worse!; (3) everybody does it!; (4) why exaggerate?; (5) I will do it tomorrow!; (6) maybe if …; (7) it is not used anymore!; (8) be a cousin not a brother!; (9) I need to be thanked!; (10) don't eat your own head, let it be!; (11) I can't possibly accomplish it!; (12) I don't feel like doing it!; (13) I am fed up!; (14) I am not worthwhile! These crutches jeopardize good research and thoughtful learned publications.

Kinematics study of a 10 degrees-of-freedom lower extremity exoskeleton for crutch-less walking rehabilitation.

BACKGROUND: Wearable lower extremity exoskeletons can provide walking assistance for the physical rehabilitation of paralyzed individuals. However, most of the existing exoskeletons require crutches to maintain balance, thus a self-balancing type is needed to improve applicability. OBJECTIVE: The purpose of this work is to study the kinematic characteristics of a novel lower extremity exoskeleton for crutch-less walking rehabilitation, and evaluate the movement performance through practical experiments. METHODS: Based on the human lower limb structure and movement characteristics, a fully actuated 10 degrees-of-freedom (DoF) lower extremity exoskeleton was proposed. The kinematic characteristics of the exoskeleton were analyzed by the D-H method and geometric method, and the model validity was verified through simulations and experiments. RESULTS: The closed-form solutions for both forward and inverse kinematics models were obtained. The consistent results of theoretical calculation and numerical simulation have shown the accuracy of the established models. The practical experiments regarding six trials have demonstrated the movement performance of the proposed exoskeleton, including sit, stance, leg extension/flexion, and left/right swing. CONCLUSIONS: The kinematic characteristics of the proposed 10-DoF lower extremity exoskeleton are similar to the human lower limb, and it could meet the motion demands of crutch-less walking rehabilitation.

Pain mapping and health-related conditions in relation to forearm crutch usage: A cross-sectional study.

To explore pain complaints and health-related conditions, verifying if permanent or temporary usage of forearm crutches could be associated with them. We designed a cross-sectional study from a sample who answered a five-month public call. We organized data into five domains: (1) diseases, signs and symptoms; (2) personal factors related to age, sex, marital status, and paid occupation; (3) body structure and functional components defined by body mass index, arterial pressure, mental state, and pain; (4) activities and participation assessed by satisfaction with Assistive Technology; (5) and environmental factors focused on medicines and forearm crutch usage. The sample was geo-referenced by address, and the frequency of the codified health conditions was distributed according to ICD-10's chapters. We recruited three times more permanent than temporary users dealing with chronic and external causes of diseases. Pain mapping suggested different pattern of complaints between permanent and temporary users. Women who were temporary users seemed more likely to be injured because of external causes. Moreover, both users reported intense (31%) and moderate (53%) levels of pain. In contrast, mild pains were only reported by permanent users (16%), suggesting a distinction between acute and chronic pain according to the kind of forearm crutch usage.

The Effect of Crutch Gait Pattern on Shoulder Reaction Force when Walking with Lower Limb Exoskeletons.

Lower limb exoskeleton robots have shown great potential in assistive and rehabilitative applications, allowing individuals with motor impairment, such as spinal cord injury (SCI) patients, to perform overground gait. Most assistive lower limb exoskeletons require users to use crutches to balance themselves during standing and walking. However, long-term crutch usage has been demonstrated to be potentially harmful to the shoulder joints, due to the repetitive high shoulder reaction forces. Investigations into the shoulder loads experienced during exoskeleton use are needed to understand the extent of this harm and, if required, to reduce the risk of injury. In this preliminary study, the effects of different gait patterns on the shoulder load are investigated in an experiment involving three able-bodied individuals. Specifically, the differences in shoulder load during exoskeleton walking are studied with two commonlyobserved gait patterns: (1) the four-point parallel crutch gait and (2) the four-point reciprocal crutch gait. Contact forces between the ground and the human-exoskeleton system were recorded and used to indicate shoulder reaction force. The results suggested no significant differences in maximum force and maximum rate of loading between the two crutch gait patterns, and only minor differences in force time integral. This indicates that shoulder reaction force may not be a significant factor when choosing between crutch gaits during exoskeleton use.

Versatile GCH Control Software for Correction of Loads Applied to Forearm Crutches During Gait Recovery Through Technological Feedback: Development and Implementation Study.

BACKGROUND: Measuring weight bearing is an essential aspect of clinical care for lower limb injuries such as sprains or meniscopathy surgeries. This care often involves the use of forearm crutches for partial loads progressing to full loads. Therefore, feasible methods of load monitoring for daily clinical use are needed. OBJECTIVE: The main objective of this study was to design an innovative multifunctional desktop load-measuring software that complements GCH System 2.0-instrumented forearm crutches and monitors the applied loads, displaying real-time graphical and numerical information, and enabling the correction of inaccuracies through feedback technology during assisted gait. The secondary objective was to perform a preliminary implementation trial. METHODS: The software was designed for indoor use (clinics/laboratories). This software translates the crutch sensor signal in millivolts into force units, records and analyzes data (10-80 Hz), and provides real-time effective curves of the loads exerted on crutches. It covers numerous types of extrinsic feedback, including visual, acoustic (verbal/beeps), concurrent, terminal, and descriptive feedback, and includes a clinical and research use database. An observational descriptive pilot study was performed with 10 healthy subjects experienced in bilateral assisted gait. The Wilcoxon matched-pairs signed-rank test was used to evaluate the load accuracy evolution of each subject (ie, changes in the loads exerted on crutches for each support) among various walks, which was interpreted at the 95% confidence level. RESULTS: GCH Control Software was developed as a multifunctional desktop tool complementing GCH System 2.0-instrumented forearm crutches. The pilot implementation of the feedback mechanism observed 96/100 load errors at baseline (walk 0, no feedback) with 7/10 subjects exhibiting crutch overloading. Errors ranged from 61.09% to 203.98%, demonstrating heterogeneity. The double-bar feedback found 54/100 errors in walk 1, 28/100 in walk 2, and 14/100 in walk 3. The first walk with double-bar feedback (walk 1) began with errors similar to the baseline walk, generally followed by attempts at correction. The Wilcoxon matched-pairs signed-rank test used to evaluate each subject's progress showed that all participants steadily improved the accuracy of the loads applied to the crutches. In particular, Subject 9 required extra feedback with two single-bar walks to focus on the total load. The participants also corrected the load balance between crutches and fluency errors. Three subjects made one error of load balance and one subject made six fluctuation errors during the three double-bar walks. The latter subject performed additional feedback with two balance-bar walks to focus on the load balance. CONCLUSIONS: GCH Control Software proved to be useful for monitoring the loads exerted on forearm crutches, providing a variety of feedback for correcting load accuracy, load balance between crutches, and fluency. The findings of the complementary implementation were satisfactory, although clinical trials with larger samples are needed to assess the efficacy of the different feedback mechanisms and to select the best alternatives in each case.