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BACKGROUND: Different factors can influence the performance of postural control (PC), one of them being muscle function, which emerges as the neuromuscular capacity to generate tension adaptable to postural disturbances in the lower limbs. AIM: To investigate the influence of joint torque parameters of the lower limbs (hip, knee, and ankle) on the variables of postural balance, analyzed by static posturography in young adults. METHOD: This study included 25 young adults (23.08 ± 4.44 years) who were submitted to motor tasks alternating: the base of support; the surface and vision conditions on a force plate. Joint torque was measured using an isokinetic dynamometer. RESULTS: The hip-abduction, -adduction, and -extension torques were negatively associated with the variables of center of pressure displacement in several conditions, both the most challenging and the least challenging ones. The ankle torque (dorsiflexion and plantar flexion) was negatively associated with postural control only in the semi-tandem condition with a rigid surface and eyes open. On the other hand, the knee torque was positively associated with the center of pressure displacement. Power measurements were more associated with postural control than peak torque. CONCLUSION: In young adults, there seems to be a greater use of the hip strategy, with greater influence of hip torque in relation to ankle torque for postural balance control. Therefore, the strengthening of hip muscles could have an impact on postural control in young adults. [ABSTRACT FROM AUTHOR]

Gait alterations in those with mild unilateral knee pain during walking may provide clues to modifiable alterations that affect progression of knee pain and osteoarthritis (OA). To examine this, we applied machine learning (ML) approaches to gait data from wearable sensors in a large observational knee OA cohort, the Multicenter Osteoarthritis (MOST) study. Participants completed a 20-m walk test wearing sensors on their trunk and ankles. Parameters describing spatiotemporal features of gait and symmetry, variability and complexity were extracted. We used an ensemble ML technique ("super learning") to identify gait variables in our cross-sectional data associated with the presence/absence of unilateral knee pain. We then used logistic regression to determine the association of selected gait variables with odds of mild knee pain. Of 2066 participants (mean age 63.6 [SD: 10.4] years, 56% female), 21.3% had mild unilateral pain while walking. Gait parameters selected in the ML process as influential included step regularity, sample entropy, gait speed, and amplitude dominant frequency, among others. In adjusted cross-sectional analyses, lower levels of step regularity (i.e., greater gait variability) and lower sample entropy(i.e., lower gait complexity) were associated with increased likelihood of unilateral mild pain while walking [aOR 0.80 (0.64–1.00) and aOR 0.79 (0.66–0.95), respectively]. [ABSTRACT FROM AUTHOR]

This study aimed to compare a biaxial ankle-foot orthosis (AFO) with a lateral wedge insole in terms of the biomechanical and clinical outcomes in individuals with knee osteoarthritis. A cross-over randomized design was used where 31 individuals (25 females and six males, mean age of 52.19 ± 4.12 years) with knee osteoarthritis wore each intervention for two weeks with two weeks washout period. Three-dimensional kinematic and kinetic data and clinical outcomes were collected to evaluate the effects of each intervention on knee adduction moment (KAM), pain, stiffness, and function. Both orthoses significantly improved pain by 17 and 22%, function by 11 and 14%, the first peak KAM by 15.7 and 19.2%, the second peak KAM by 10.4 and 16.7%, and KAM impulse by 14.8 and 22.2%, respectively. However, the biaxial AFO significantly reduced the KAM and improved function compared to the lateral wedge insole (p < 0.01). The results of this study have shown that both orthoses have a potential role in the conservative management of medial knee osteoarthritis. The biaxial AFO proved statistically better at improving function and KAM; though these differences do not seem to be clinically significant. Orthotic interventions have been reported to be effective in the management of medial knee osteoarthritis. Lateral wedge insole and biaxial ankle-foot orthosis (AFO) are effective in the improvement of pain, function, and knee adduction moment (KAM) in people with medial knee osteoarthritis. The biaxial AFO, compared with lateral wedge insole, contributes to statistically more improvement of function and KAM. However, these differences do not seem to be clinically significant. [ABSTRACT FROM AUTHOR]

Lumbar spondylosis (LS) is a common degenerative spine disease that often leads to impaired motor control, sensory changes, and imbalance. The current study aimed to compare the dynamic balance control between patients with LS and healthy controls in terms of inclination angles (IA) and the rate of change of IA (RCIA) of the center of mass relative to the center of pressure (COM–COP motion) during walking and to identify the correlation between dynamic balance and standing balance in patients with LS. Eleven patients with LS and eleven healthy controls performed level walking and static standing in a gait laboratory while their whole-body motion and ground reaction forces were measured to calculate the IA and RCIA. Gait temporal–spatial parameters were also recorded. Correlations between the COP motions during standing balance and COM–COP motions during gait were quantified using Pearson's correlation coefficients (r). In the sagittal plane, the patients increased posterior IA with decreased posterior RCIA during the double-limb support phase of gait and showed decreased anterior RCIA, with small ranges of IA and RCIA during the single-limb support phase (p < 0.05). In the frontal plane, the patients increased medial–lateral ranges of RCIA and medial IA during the double-limb support phase of gait and increased medial RCIA and ranges of IA during the single-limb support phase of gait (p < 0.05). A moderate to strong correlation was found between dynamic balance and standing balance in the patients (p < 0.05). The patients presented a conservative anterior–posterior dynamic balance control but an unstable medial–lateral dynamic balance control during walking, which may be related to the decreased gait speed. The results showed that the greater the postural sway in the patients' standing balance, the more conservative the dynamic balance control in the sagittal plane, and the greater the risk of imbalance in the frontal plane. It is thus suggested that dynamic balance control deviations during gait in patients with LS cannot be deduced solely from standing balance test data, and should thus be monitored via dynamic approaches in clinical applications. [ABSTRACT FROM AUTHOR]

Objective: The outcome of congenital clubfoot treatment is still challenging if the feet deformities are not completely corrected. Here we explore a minimal invasive procedure with an eight‐plate implant to correct the residual forefoot adduction deformity after treatment of neglected or relapsed clubfoot. Methods: We retrospectively reviewed patients with residual forefoot adduction deformity after clubfoot treatment between January 2013 and June 2016. The patients underwent temporary epiphysiodesis of the lateral column of the mid‐foot, which in detail, an eight‐plate was placed on each side of the calcaneocuboid joint. The foot deformities were recorded according to the weight‐bearing radiographic measurements including talo‐first metatarsal angle, calcaneo‐fifth metatarsal angle and medial‐to‐lateral column length. Results: A total of 13 patients (20 feet) with an average age of 7.8 years old were located with an average duration of 40.8 months follow‐up (range, 28 to 54 months). The average talo‐first metatarsal angle improved from 28.3° (range, 19° to 47°) preoperatively to 8.3° (range, 3° to 18°) and the calcaneo‐fifth metatarsal angle improved from 29.1° (range, 19° to 40°) preoperatively to 8.4° (range, 0° to 21°) at final follow‐up. The mean ratio of the medial‐to‐lateral column length improved from 1.14 ± 0.06 to 1.55 ± 0.09 with statistical significance (t = 3.566; P < 0.001). Conclusions: Eight‐plate epiphysiodesis is an easy and effective method for the correction of residual forefoot adduction deformity after clubfoot treatment in growing children without the need of osteotomy. [ABSTRACT FROM AUTHOR]

Vascular malformations of the muscle are rare non-proliferative vascular lesions, and few case reports have described intramuscular vascular malformations in the upper extremities. Vascular malformations of the muscle may produce musculoskeletal deformities due to muscle contracture. Symptomatic intramuscular vascular malformations are commonly treated with surgery and interventional management. We report a vascular malformation that could not be completely resected. It caused adduction contracture of the thumb in the hand. Sclerotherapy was performed before surgery, but the contracture did not improve. Thus, we additionally performed adductor tenotomy. There was no evidence of recurrence during 6 months of follow-up. [ABSTRACT FROM AUTHOR]

Introduction: We report a case of large angle exotropia in a child with limitation of adduction in the left eye with a radiological finding of hypoplastic medial rectus. Methods: A 3- year- old male child presented with left eye large angle exotropia, left face turn, -4 adduction limitation and severe amblyopia. Orbital imaging revealed hypoplasia of the medial rectus and intraoperatively a thin medial rectus was noted. The surgical procedure planned was lateral rectus recession combined with Modified Nishida's technique in the left eye. In this technique the superior and inferior recti were transposed medially by inserting non-absorbable sutures in the sclera posteriorly, closer to the upper and lower borders of the medial rectus muscle. Result: There was improvement in adduction of left eye and reduction of original deviation following maximal lateral rectus recession and a modified Nishida's approach. The early and optimal correction of exotropia also improved the compliance to patching with subsequent gain in visual acuity of the amblyopic eye. Conclusion: Modified Nishida's technique has the advantage of no muscle splitting and no tenotomy, remains a less invasive surgical procedure to correct large deviations. The modification of placing the bellies closer to medial rectus augments the effect and further improves adduction in cases with severe limitation of adduction. This technique can thus be considered as a possible surgical approach in young children with large angle exotropia due to hypoplastic medial rectus. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the amplitude of movement in anophthalmic sockets reconstructed with conical or spherical orbital implants with and without an external ocular prosthesis (EOP), and whether the fornix depth could play a role. Methods: Prospective observational study involving unilateral anophthalmic sockets evaluated the amplitude of movement with conical (20 subjects) or spherical (16) non-porous orbital implants, with and without an EOP, having the contralateral eye as the control group. Standardized photographs were obtained in the four gaze directions and measurements were performed using the Image J software. The upper and lower fornix depths were measured using rulers. Results: Compared to the contralateral eye, the median movement amplitude without EOP was smaller with conical implants in supraduction (−0.88 mm, p=0.008), abduction (−2.26 mm, p<0.001) and adduction (−0.91 mm, p=0.008). Spherical implants had reduced movement only in abduction (−2.63 mm, p<0.001). Conical and spherical implants had similar amplitudes of movement in all versions, and were always smaller compared to the control. The median movement amplitude with the EOP was −3.05 mm (p=0.001) than without the EOP in abduction and −2.07 mm (p=0.020) in adduction, regardless of implant format. The fornix depth did not affect the orbital implants or EOP movement amplitude's median. Conclusion: Conical and spherical implants provide similar amplitude of movement and fornix depth did not have an influence on it. The amplitude of movement was significantly limited compared to the contralateral eye and was even more reduced if the EOP was in place with conical or spherical implant formats. [ABSTRACT FROM AUTHOR]

A 61-year-old man underwent left medial wall and floor fracture repair with a Suprafoil® implant. He had postoperative orbital congestion and lower eyelid swelling that persisted for over seven weeks. Examination demonstrated hyperglobus with supraduction, infraduction, and adduction deficits. Imaging revealed a 3.7 × 3.6 × 2.6 cm isodensity along the implant, thought to be hematoma. The patient elected to pursue exploration and possible drainage. Intraoperatively, there was no hematoma; rather, we found a fibroinflammatory rind along the periorbita surrounding the implant. This was biopsied, and the implant was removed, as the fractures had sufficiently healed. Pathology showed dense fibroconnective tissue with associated inflammation. The patient completed a steroid taper with improvement in all symptoms and resolution of diplopia. To our knowledge, this is the first reported case of such a prominent orbital inflammatory reaction to nylon foil, a departure from the delayed hematic cysts typically associated with these implants. [ABSTRACT FROM AUTHOR]

The purpose of this study was to improve our understanding of the relative contributions of biomechanical, anthropometric, and psychological factors in explaining maximal bench press (BP) strength in a heterogeneous, resistance-trained sample. Eighteen college-aged participants reported to the laboratory for three visits. The first visit consisted of psychometric testing. The second visit assessed participants' anthropometrics, additional psychometric outcomes, and bench press one repetition maximum (1RM). Participants performed isometric dynamometry testing for horizontal shoulder adduction and elbow extension at a predicted sticking point joint position. Multiple linear regression was used to examine the relationships between the biomechanical, anthropometric, and psychological variables and BP 1RM. Our primary multiple linear regression accounted for 43% of the variance in BP strength (F(3,14) = 5.34, p = 0.01; R2 = 0.53; adjusted R2 = 0.43). The sum of peak isometric net joint moments from the shoulder and elbow had the greatest standardized effect (0.59), followed by lean body mass (0.27) and self-efficacy (0.17). The variance in BP 1RM can be similarly captured (R2 = 0.48) by a single principal component containing anthropometric, biomechanics, and psychological variables. Pearson correlations with BP strength were generally greater among anthropometric and biomechanical variables as compared to psychological variables. These data suggest that BP strength among a heterogeneous, resistance-trained population is explained by multiple factors and is more strongly associated with physical than psychological variables. [ABSTRACT FROM AUTHOR]

In-shoe systems and pressure plates are used to assess plantar pressure during gait, but additional tools are employed to evaluate other gait parameters. The GAITRite® system is a clinical gait evaluation tool. Extensive literature is available for spatiotemporal parameters, but it is scarce for relative plantar pressure data. Therefore, we investigated whether, when controlling for age, the GAITRite® system is able to distinguish the effects of walking velocity on plantar pressure parameters in six plantar regions in a large sample of adults. Participants (83 women and 87 men, aged 18–85 years) walked at three self-selected velocities (slow, preferred, fast) on a 6-m long GAITRite® walkway. Relative peak pressure, pressure-time integral, peak time and contact area were computed for six zones (lateral and medial heel, mid- and forefoot). The impact of age (covariate), sex, side, velocity, pressure zone and their interactions on pressure variables was evaluated. Velocity affected peak pressure, pressure-time integral, peak time and contact area (p < 0.001). With increasing self-selected gait velocity, medial forefoot peak pressure and pressure-time integral increased (p < 0.001), while heel and lateral forefoot regions displayed a nonlinear plantar pressure evolution. These results suggest lower (heel strike) or more equally distributed (push-off) loads at preferred gait velocity. [ABSTRACT FROM AUTHOR]

• A novel teleoperation system for dexterous micromanipulation with a 3D three-fingered electrothermal microgripper is built. • Implementing micromanipulation using primary-secondary operation to improve intuition. • Lightweight exoskeleton hand is designed to be easily worn on human fingers. • The system involved enables multi-functional operation on micro-objects even for untrained operators. In this article, we present a novel teleoperation system for dexterous micromanipulation with a 3D three-fingered electrothermal microgripper. A lightweight wearable exoskeleton hand is designed and employed as the primary device, integrating rotational potentiometers as angle sensors, which are embedded in a closed-loop kinematic chain for detecting flexion/extension and adduction/abduction angles of motion. The measured angles are subsequently translated into exoskeleton hand-fingertip positions utilized as the primary inputs. A 3D electrothermal microgripper based tele-micro manipulation system is realized. The displacement of the exoskeleton fingertips is harnessed to govern the actions of the microgripper via an effective position incremental control method. Furthermore, the system's capabilities are exemplified through intricate micromanipulations performed on soft zebrafish embryos. The micromanipulations encompass gripping and rotational maneuvers. The outcomes of empirical experimentation clearly demonstrate the suitability of the macro-micro teleoperation system, which incorporates an exoskeleton hand for controlling a microgripper in 3D micromanipulation. The system improves operator comfort and maneuvering efficiency. Even for untrained users, the tasks can be accomplished with ease in an intuitive and effective way. [ABSTRACT FROM AUTHOR]

This article discusses the determinants of gait dystonia severity in individuals with cerebral palsy (CP). Dystonia, a movement condition, is often under-diagnosed in people with CP, particularly in the legs. The study found that only 13% of people with CP and leg dystonia had their condition diagnosed during a CP clinic visit. Expert clinicians identified leg adduction variability and amplitude as the key features used to diagnose and determine the severity of dystonia. The article suggests that recognizing these features can aid clinicians and individuals with CP in diagnosing dystonia more effectively. [Extracted from the article]

We report the case of an 8-month-old infant born at 33 weeks' gestation referred to our institution for evaluation of left eye abduction deficit and microcephaly. Ophthalmic examination revealed a left eye abduction deficit with palpebral fissure narrowing on adduction along with palpebral fissure widening on abduction, consistent with Duane syndrome. Genetic testing revealed a pathogenic EP300 mutation confirming Rubinstein-Taybi syndrome type II. The cooccurrence of Duane syndrome and Rubinstein-Taybi syndrome is rare, with only 3 cases in the literature, 2 with genetic confirmation. Potential involvement of the cranial nerves in Rubinstein-Taybi syndrome may explain its cooccurrence with Duane syndrome, which is seemingly more common in EP300-mediated disease. [ABSTRACT FROM AUTHOR]

Context: A limiting factor for reducing anterior cruciate ligament injury risk is ensuring that the movement adaptions made during the prevention program transfer to sport-specific activity. Virtual reality provides a mechanism to assess transferability, and neuroimaging provides a means to assay the neural processes allowing for such skill transfer. Objective: To determine the neural mechanisms for injury risk–reducing biomechanics transfer to sport after anterior cruciate ligament injury prevention training. Design: Cohort study. Setting: Research laboratory. Participants: Four healthy high school soccer athletes. Interventions: Participants completed augmented neuromuscular training utilizing real-time visual feedback. An unloaded knee extension task and a loaded leg press task were completed with neuroimaging before and after training. A virtual reality soccer-specific landing task was also competed following training to assess transfer of movement mechanics. Main Outcome Measures: Landing mechanics during the virtual reality soccer task and blood oxygen level–dependent signal change during neuroimaging. Results: Increased motor planning, sensory and visual region activity during unloaded knee extension and decreased motor cortex activity during loaded leg press were highly correlated with improvements in landing mechanics (decreased hip adduction and knee rotation). Conclusion: Changes in brain activity may underlie adaptation and transfer of injury risk–reducing movement mechanics to sport activity. Clinicians may be able to target these specific brain processes with adjunctive therapy to facilitate intervention improvements transferring to sport. [ABSTRACT FROM AUTHOR]

Clinical Scenario: Shoulder range of motion (ROM) in throwing athletes relies on a balance of mobility and stability to maintain proper function and health that, if disrupted, can lead to shoulder injury. There have been several studies that address the relationship between ROM deficits and overhead injuries; however, it may be unclear to clinicians which interventions are most effective for increasing ROM in the glenohumeral joints of overhead athletes. Clinical Question: In overhead athletes who have deficient shoulder ROM, is instrument-assisted soft tissue mobilization (IASTM) more effective at acutely increasing ROM over the course of a patient’s treatment when compared with self-stretching? Summary of Key Findings: A thorough literature review yielded 3 studies relevant to the clinical question, and all 3 studies were included. Two articles found a significant increase in acute ROM when compared with a self-stretch measure. All 3 articles showed increases in internal rotation and horizontal adduction, and 1 study reported an increase in total arc of shoulder ROM. Clinical Bottom Line: There is moderate evidence to support the use of IASTM to acutely increase ROM in the glenohumeral joint of overhead athletes. Clinicians should be aware of the variability with recommended treatment times; however, positive results have been seen with treatments lasting 5 to 6 minutes per treatment region. There is no consensus for treatment intensity, and certain IASTM tools require certification. Strength of Recommendation: Grade B evidence exists that IASTM is more effective at increasing shoulder ROM (ie, internal rotation, horizontal adduction, external rotation, total arc of motion) in overhead athletes than self-stretching measures. [ABSTRACT FROM AUTHOR]

Given its apparent representation of cumulative (vs peak) loads, this feasibility study investigates vertical ground reaction impulse (vGRI) as a real-time biofeedback variable for gait training aimed at reducing lower limb loading. Fifteen uninjured participants (mean age = 27 y) completed 12 2-min trials, 1 at each combination of 4 walking speeds (1.0, 1.2, 1.4, and 1.6 m/s) and 3 targeted reductions in vGRI (5, 10, and 15%) of the assigned ("target") limb, with the latter specified relative to an initial baseline (no feedback) condition at each speed. The ability to achieve targeted reductions was assessed using step-by-step errors between measured and targeted vGRI. Mean (SD) errors were 5.2% (3.7%); these were larger with faster walking speeds but consistent across reduction targets. Secondarily, we evaluated the strategy used to modulate reductions (ie, stance time or peak vertical ground reaction force [vGRF]) and the resultant influences on knee joint loading (external knee adduction moment [EKAM]). On the targeted limb, stance times decreased (P < .001) with increasing reduction target; first and second peaks in vGRF were similar (P > .104) across all target conditions. While these alterations did not significantly reduce EKAM on the target limb, future work in patients with knee pathologies is warranted. [ABSTRACT FROM AUTHOR]

Vertical stiffness may contribute to lower-extremity injury risk; however, it is unknown whether athletes with different stiffness levels display differences in biomechanics. This study compared differences in biomechanics between female athletes (n = 99) with varying stiffness levels during a repetitive, single-leg, vertical hopping task. Vertical stiffness was calculated as the ratio of peak vertical ground-reaction force to maximum center-of-mass displacement. Tertiles were established using stiffness values, and separate 1-way ANOVAs were used to evaluate between-group differences. Stance times decreased, and flight times, ground-reaction force, and stiffness increased, from the low- to high-stiffness group (P < .050). The high-stiffness group displayed: (1) greater lateral trunk flexion (P = .009) and lesser hip adduction (P = .022) at initial ground contact compared to the low- and moderate-stiffness groups, respectively; (2) lesser peak hip adduction compared to the low-stiffness group (P = .040); (3) lesser lateral trunk-flexion (P = .046) and knee-flexion (P = .010) excursion compared to the moderate- and low-stiffness groups, respectively; and (4) greater peak hip-flexion (P = .001), ankle-dorsiflexion (P = .002), and ankle-eversion (P = .038) moments compared to the low-stiffness group. A wide range of variability in stiffness exists within a relatively homogenous population. Athletes with varying stiffness levels display biomechanical differences that may help identify the potential mechanism(s) by which stiffness contributes to injury risk. [ABSTRACT FROM AUTHOR]

The inertial measurement unit (IMU)-to-segment (I2S) alignment is an important part of IMU-based joint angle estimation, and the accurate estimation of the three degree of freedom (3-DOF) knee angle can provide practical support for the evaluation of motions. In this paper, we introduce a dynamic weight particle swarm optimization (DPSO) algorithm with crossover factor based on the joint constraint to obtain the dynamic alignment vectors of I2S, and use them to perform the quaternion-based 3-DOF knee angle estimation algorithm. The optimization algorithm and the joint angle estimation algorithm were evaluated by comparing with the optical motion capture system. The range of 3-DOF knee angle root mean square errors (RMSEs) is 1.6°–5.9° during different motions. Furthermore, we also set up experiments of human walking (3 km/h), jogging (6 km/h) and ordinary running (9 km/h) to investigate the effects of dynamic I2S misalignment errors on 3-DOF knee angle estimation during different motions by artificially adding errors to I2S alignment parameters. The results showed differences in the effects of I2S misalignment errors on the estimation of knee abduction, internal rotation and flexion, which indicate the differences in knee joint kinematics among different motions. The IMU to thigh misalignment error has the greatest effect on the estimation of knee internal rotation. The effect of IMU to thigh misalignment error on the estimation of knee abduction angle becomes smaller and then larger during the two processes of switching from walking to jogging and then speeding up to ordinary running. The effect of IMU to shank misalignment error on the estimation of knee flexion angle is numerically the largest, while the standard deviation (SD) is the smallest. This study can provide support for future research on the accuracy of 3-DOF knee angle estimation during different motions. [ABSTRACT FROM AUTHOR]

Background: A typical feature in infants with severe C5-C6 brachial plexus birth injury (BPBI) requiring nerve repair is the formation of shoulder internal rotation contracture (IRC). The underlying pathophysiological mechanism is unknown, and the sequelae can be difficult to treat. The severity of the IRC differs among children. C5-C6 lesions are heterogeneous at the root level. Our null hypothesis was that the type of root-level lesion (axonotmesis or neurotmesis versus avulsion) was not associated with the extent of IRC formation over time in children with upper-trunk BPBI.Methods: We performed a retrospective analysis of all patients with upper-trunk BPBI who underwent primary surgery of the C5 and/or C6 spinal nerves between 1990 and 2020 and had follow-up of at least 2 years. The primary outcome was passive shoulder external rotation (ER) in adduction at 1, 3, 5, 7, and 15 years of age. The secondary outcome was whether additional shoulder surgery was performed. The relationship between the nature of the C5-C6 lesion and IRC formation was analyzed using linear mixed models. The Kaplan-Meier method was used to estimate the cumulative risk of secondary shoulder procedures.Results: In total, 322 patients were analyzed; mean follow-up was 7.2 ± 4.6 years. The C5-C6 root lesion type was significantly related to the passive range of ER (overall test in linear mixed model, p = 0.007). Children with avulsion of C5 and C6 (n = 21) had, on average, 18° (95% confidence interval [CI], 6.3° to 30°) less IRC formation than those with neurotmesis of C5 and C6 (n = 175) and 17° (2.9° to 31°) less than those with neurotmesis of C5 and avulsion of C6 (n = 34). IRC formation did not differ between the neurotmesis C5-C6 and neurotmesis C5-avulsion C6 groups. Secondary shoulder procedures were performed in 77 patients (10-year risk, 28% [95%CI, 23% to 34%]).Conclusions: Shoulder IRC formation in infants with BPBI with surgically treated C5-C6 lesions occurs to a lesser degree if the C5 root is avulsed than when C5 is neurotmetic. This finding provides insight into the possible causative pathoanatomy and may ultimately lead to strategies to mitigate IRC.Level Of Evidence: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Backward walking (BW) has been recommended as a rehabilitation intervention to prevent, manage, or improve diseases. However, previous studies showed that BW significantly increased the first vertical ground reaction force (GRF) during gait, which might lead to higher loading at the knee. Published reports have not examined the effects of BW on medial compartment knee loading. The objective of this study was to investigate the effects of BW on external knee adduction moment (EKAM). Twenty-seven healthy adults participated in the present study. A sixteen-camera three-dimensional VICON gait analysis system, with two force platforms, was used to collect the EKAM, KAAI, and other biomechanical data during BW and forward walking (FW). The first (P < 0.001) and second (P < 0.001) EKAM peaks and KAAI (P = 0.02) were significantly decreased during BW when compared with FW. The BW significantly decreased the lever arm length at the first EKAM peak (P = 0.02) when compared with FW. In conclusion, BW was found to be a useful strategy for reducing the medial compartment knee loading even though the first peak ground reaction force was significantly increased. [ABSTRACT FROM AUTHOR]

Tractional tethering by the optic nerve (ON) on the eye as it rotates towards the midline in adduction is a significant ocular mechanical load and has been suggested as a cause of ON damage induced by repetitive eye movements. We designed an ocular finite element model (FEM) simulating 6° incremental adduction beyond the initial configuration of 26° adduction that is the observed threshold for ON tethering. This FEM permitted sensitivity analysis of ON tethering using observed material property variations in measured hyperelasticity of the anterior, equatorial, posterior, and peripapillary sclera; and the ON and its sheath. The FEM predicted that adduction beyond the initiation of ON tethering concentrates stress and strain on the temporal side of the optic disc and peripapillary sclera, the ON sheath junction with the sclera, and retrolaminar ON neural tissue. However, some unfavorable combinations of tissue properties within the published ranges imposed higher stresses in these regions. With the least favorable combinations of tissue properties, adduction tethering was predicted to stress the ON junction and peripapillary sclera more than extreme conditions of intraocular and intracranial pressure. These simulations support the concept that ON tethering in adduction could induce mechanical stresses that might contribute to ON damage. [ABSTRACT FROM AUTHOR]

Purpose: To report the surgical effects of a combination treatment comprising the lateral rectus belly transposition (LRBT) procedure, without muscle splitting or disinsertion, and ipsilateral antagonist recession for vertical rectus palsy. Methods: The medical records of consecutive patients who underwent the LRBT procedure between 2017 and 2020 were reviewed. Preoperative and postoperative deviation in primary position, preoperative and postoperative scale of duction of the palsied muscle, any induced horizontal or torsional deviation, and other complications were collected. Results: Thirteen patients were identified: 10 with inferior rectus palsy and 3 with superior rectus palsy. The mean postoperative follow-up time was 20.4 ± 8.0 months. Eleven patients (84.6%) underwent simultaneous recession of the ipsilateral antagonist muscle of the palsied vertical rectus. After surgery, the mean vertical deviation improved from 31.4 ± 16.4 to 1.9 ± 3.6 prism diopters (PD) (P <.001). The mean vertical duction limitation of the palsied muscle improved from −2.7 ± 0.6 to −0.6 ± 0.5 (P =.001). In one patient, the scleral fixation suture was removed due to continuous reverse vertical diplopia. The total success rate was 76.9%. No induced horizontal deviation was noted. Anterior segment ischemia or other severe surgical complications did not occur. Conclusions: The LRBT procedure can be effective, safe, and reversible in patients with vertical rectus palsy. It allows for the option of simultaneous ipsilateral antagonist recession, and it is especially valuable in patients whose vertical duction deficiency is worse in abduction but mild in adduction. [J Pediatr Ophthalmol Strabismus. 2022;59(6):396–404.] [ABSTRACT FROM AUTHOR]

The objectives of this study were to 1) assess the differences between youth soccer and basketball players with and without past year groin pain (GP) in hip adduction and abduction strength and several training characteristics (age at the start of regular training, weekly training frequency, warm-up and training duration, use of stretching and/or stabilisation exercises during warm-up, use of resistance training); 2) present strength reference values for youth soccer and basketball players. 227 players participated (age 16.9 ± 1.4 years; height 184.2 ± 8.5 cm; mass 75.5 ± 11.9 kg). Hip adduction and abduction strength was measured in supine position (hip, knee and ankle in neutral position) using a MuscleBoard dynamometer. Interlimb asymmetries and hip adduction:abduction ratios were calculated. Past year GP and training characteristics were assessed with a retrospective questionnaire. 11.9% of players reported past year GP (16.9% in soccer and 6.4% in basketball). The only significant difference between the past year GP and the control groups was found in the age of the players at the start of regular training (7.2 ± 1.8 years for the GP group vs. 8.5 ± 2.6 years for the control group). Additionally, soccer players without past year GP have significantly higher hip adduction strength (1.1 ± 0.2 Nm/kg vs. 1.0 ± 0.2 Nm/kg) and adduction:abduction strength ratio (1.10 ± 0.18 vs. 1.03 ± 0.16) compared to basketball players. Our results show that hip adduction and abduction strength, interlimb asymmetry and hip adduction:abduction ratio do not differentiate between players with and without past year GP (p = 0.29–0.90), which means that their adduction or abduction strength can be analysed regardless of the GP presence in the past year. Additionally, players with past year GP started regularly training at significantly lower age, which could indicate the problematic nature of early/premature sports specialisation. [ABSTRACT FROM AUTHOR]

The proprioceptive neuromuscular facilitation (PNF) techniques such as contract-relax-antagonist-contract and contract-relax have been adopted by the researchers in the clinical area to investigate their efficacy on hemiplegic patient. This study investigated 4-week PNF exercise on the gait impaired hemiplegic participants measured with the Visual gait assessment scale-a 3 sectioned scale. Fourteen male and six female hemiplegic gait impaired participants (mean age 49.1 ± 7.8 years) were recruited into the study and treated for PNF protocol twice a day for 4 weeks. In the swing phase participants shows having decreased internal rotation (25%) and adduction (25%) and increased external rotation (47.5%) and abduction (42.5%) in hip and pelvis, normal knee movement (42.5%), and normal ankle/foot movement (12.5%) in the 4th week of intervention. In the stance phase, the participants show having decreased internal rotation (27.5%) and adduction (32.5%), increased external rotation (40%), abduction (42.5%) in hip and pelvis, normal knee movement (10%), normal ankle/foot movement (50%) in the 4th week of intervention. In the late stance phase, the participants show having decreased internal rotation (30%) and adduction (25%), increased external rotation (30%) and abduction (27.5%) in hip and pelvis, normal knee movement (32.5%) and normal ankle/foot movement (55%) in the 4th week of intervention. It has been seen, there is a significant change in excessive internal rotation, excessive external rotation, excessive abduction, excessive adduction, knee movement, and the ankle/foot movement i.e., p= <0.05. PNF exercise is an effective, easy to apply and potentially risk-free intervention for hemiplegic patients after stroke patients. [ABSTRACT FROM AUTHOR]

Purpose: Greater articular cartilage T1ρ magnetic resonance imaging relaxation times indicate less proteoglycan density and are linked to posttraumatic osteoarthritis development after anterior cruciate ligament reconstruction (ACLR). Although changes in T1ρ relaxation times are associated with gait biomechanics, it is unclear if excessive or insufficient knee joint loading is linked to greater T1ρ relaxation times 12 months post-ACLR. The purpose of this study was to compare external knee adduction (KAM) and flexion (KFM) moments in individuals after ACLR with high versus low tibiofemoral T1ρ relaxation profiles and uninjured controls. Methods: Gait biomechanics were collected in 26 uninjured controls (50% females; age, 22 ± 4 yr; body mass index, 23.9 ± 2.8 kg·m−2) and 26 individuals after ACLR (50% females; age, 22 ± 4 yr; body mass index, 24.2 ± 3.5 kg·m−2) at 6 and 12 months post-ACLR. ACLR-T1ρHigh (n = 9) and ACLR-T1ρLow (n = 17) groups were created based on 12-month post-ACLR T1ρ relaxation times using a k-means cluster analysis. Functional analyses of variance were used to compare KAM and KFM. Results: ACLR-T1ρHigh exhibited lesser KAM than ACLR-T1ρLow and uninjured controls 6 months post-ACLR. ACLR-T1ρLow exhibited greater KAM than uninjured controls 6 and 12 months post-ACLR. KAM increased in ACLR-T1ρHigh and decreased in ACLR-T1ρLow between 6 and 12 months, both groups becoming more similar to uninjured controls. There were scant differences in KFM between ACLR-T1ρHigh and ACLR-T1ρLow 6 or 12 months post-ACLR, but both groups demonstrated lesser KFM compared with uninjured controls. Conclusions: Associations between worse T1ρ profiles and increases in KAM may be driven by the normalization of KAM in individuals who initially exhibit insufficient KAM 6 months post-ACLR. [ABSTRACT FROM AUTHOR]

(1) Background: Knee osteoarthritis (OA) is a serious orthopedic problem. In this context, the high tibial osteotomy (HTO) is an established surgical procedure to reduce the load and degeneration of the affected compartment. The aim of this investigation was to judge standing steadiness and asymmetry, pain intensity and quality of life among patients who underwent HTO surgery. (2) Methods: Twenty-five male patients with medial tibiofemoral OA finished this 2 year follow-up study. Standing balance was captured using force plates with four uniaxial sensors before, 6 weeks after, 1 year after, and 2 years after HTO surgery. The percentage weight (PW) under the foot at one side, the stability (ST) index and the weight distribution (WD) index were the main outcomes. Comparisons were conducted using repeated measures analyses of variance. (3) Results: Over time, the PW under the foot at the HTO side increased on average (p < 0.001). In terms of standing steadiness, the average ST remained similar over the time points (p = 0.71). The WD index was affected by time (p = 0.003). (4) Conclusions: In order to judge short-term effects, the PW is recommended, whereas long-term effects can be identified either through the PW or the WD index. [ABSTRACT FROM AUTHOR]

Background: Acetaminophen (APAP)-associated transaminase elevation, induced by N-acetyl-p-benzoquinone imine (NAPQI) protein adduction, remains an area of research interest. Distinct from known genetic, physiologic, and dosage associations dictating severity of hepatic injury, no known factors predict an absence of protein adduct formation at therapeutic APAP dosing. Hypothesis: Sex-based physiology is predictive of APAP-induced protein adduct formation and differential metabolite expression at therapeutic doses. Methods: This retrospective study interrogated serum samples collected for a prior study investigating fluctuations of alanine aminotransferase (ALT) over time with 4G daily APAP dosing for ≥ 16 days in subjects from Denver, Colorado. Subjects were grouped by adduct formation (n = 184) vs no adducts (n = 20). Samples were run on ultra-high-performance liquid chromatography mass spectrometry from study days 0, 7, 16, and 31. Significant metabolite expressions were identified using t-tests with false discovery rate correction (FDR), partial least squares discriminant, and ANOVA simultaneous comparison analyses. Demographic and clinical data were explored using t-tests with FDR (age, weight, BMI, ALT) and Chi-square (sex, ethnicity, race) analyses. Results: In pre-treatment samples, relative quantitation caprylic acid was expressed ninefold higher and 6-carboxyhexanoate was expressed threefold lower in subjects who did not develop adducts. Lactate had greater expression in the no adducts group (p = 0.001). Using absolute quantitation, glutathione was expressed 2.6-fold greater among no adduct subjects. Odds of males developing NAPQI protein adducts at therapeutic APAP dosing were 5.91 times lower than females (95% CI = 2.3–14.9; p = 0.0001). Conclusion: Multiple metabolites were differentially expressed based on adduct group and sex. Metabolites were identified unique to adduct development independent of sex. At therapeutic APAP dosing, males were less likely to develop APAP protein adducts. Further research into lipid biosynthesis and metabolism may provide further insight into physiology associated with adduct production. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to compare the effects of scapular stabilization exercise with and without cognitive functional therapy (CFT) on disability and scapular kinematics in people suffering from chronic neck pain. Methods: A total of 72 patients with chronic non-specific neck pain were randomized into scapular stabilization exercise alone, n = 24, combined (scapular stabilization exercise + CFT), n = 24, and a control group, n = 24. Scapular kinematic and disability were measured at baseline and after the intervention. Results: Statistically significant differences in neck pain and disability scale (NPAD) were found when the multimodal physiotherapy group including a cognitive functional approach was compared with stabilization exercises group at 6 weeks (effect size (95%CI) = –1.63 (–2.55, –.71); P = 0.019)). Regarding the neck disability index (NDI), a significant between-group difference was observed at six-week (effect size (95%CI) = –2.69 (–3.80, –1.58); P = 0.007), with the superiority of effect in multimodal physiotherapy group. A significant between-group difference was observed in the scapular upward rotation and scapular osterior tilt at 30°, 60°, 90° and 120° of shoulder adduction. Conclusions: A group-based multimodal rehabilitation program including scapular stabilization exercise plus cognitive functional therapy was superior to group-based stabilization exercises alone for decreasing disability and, improving scapular kinematic in patients with chronic neck pain. [ABSTRACT FROM AUTHOR]

Background: Running-related injuries are prevalent among distance runners. Changing step rate is a commonly used running retraining strategy in the management and prevention of running-related injuries. Objective: The aims of this review were to synthesise the evidence relating to the effects of changing running step rate on injury, performance and biomechanics. Design: Systematic review and meta-analysis. Data Sources: MEDLINE, EMBASE, CINAHL, and SPORTDiscus. Results: Thirty-seven studies were included that related to injury (n = 2), performance (n = 5), and biomechanics (n = 36). Regarding injury, very limited evidence indicated that increasing running step rate is associated with improvements in pain (4 weeks: standard mean difference (SMD), 95% CI 2.68, 1.52 to 3.83; 12 weeks: 3.62, 2.24 to 4.99) and function (4 weeks: 2.31, 3.39 to 1.24); 12 weeks: 3.42, 4.75 to 2.09) in recreational runners with patellofemoral pain. Regarding performance, very limited evidence indicated that increasing step rate increases perceived exertion (− 0.49, − 0.91 to − 0.07) and awkwardness (− 0.72, − 1.38 to − 0.06) and effort (− 0.69, − 1.34, − 0.03); and very limited evidence that an increase in preferred step rate is associated with increased metabolic energy consumption (− 0.84, − 1.57 to − 0.11). Regarding biomechanics, increasing running step rate was associated with strong evidence of reduced peak knee flexion angle (0.66, 0.40 to 0.92); moderate evidence of reduced step length (0.93, 0.49 to 1.37), peak hip adduction (0.40, 0.11 to 0.69), and peak knee extensor moment (0.50, 0.18 to 0.81); moderate evidence of reduced foot strike angle (0.62, 034 to 0.90); limited evidence of reduced braking impulse (0.64, 0.29 to 1.00), peak hip flexion (0.42, 0.10 to 0.75), and peak patellofemoral joint stress (0.56, 0.07 to 1.05); and limited evidence of reduced negative hip (0.55, 0.20 to 0.91) and knee work (0.84, 0.48 to 1.20). Decreasing running step rate was associated with moderate evidence of increased step length (− 0.76, − 1.31 to − 0.21); limited evidence of increased contact time (− 0.95, − 1.49 to − 0.40), braking impulse (− 0.73, − 1.08 to − 0.37), and negative knee work (− 0.88, − 1.25 to − 0.52); and limited evidence of reduced negative ankle work (0.38, 0.03 to 0.73) and negative hip work (0.49, 0.07 to 0.91). Conclusion: In general, increasing running step rate results in a reduction (or no change), and reducing step rate results in an increase (or no change), to kinetic, kinematic, and loading rate variables at the ankle, knee and hip. At present there is insufficient evidence to conclusively determine the effects of altering running step rate on injury and performance. As most studies included in this review investigated the immediate effects of changing running step rate, the longer-term effects remain largely unknown. Prospero Registration: CRD42020167657. [ABSTRACT FROM AUTHOR]

Background: Increased hip adduction and internal rotation can lead to excessive patellofemoral joint stress and contribute to patellofemoral pain development. The gluteus maximus acts as a hip extensor, abductor, and external rotator. Improving hip extensor use by increasing one's forward trunk lean in the sagittal plane may improve frontal and transverse plane hip kinematics during stair ascent.Research Question: Does increasing forward trunk lean during stair ascent affect peak hip adduction and internal rotation?Methods: Twenty asymptomatic females performed five stair ascent trials (96 steps/min) on an instrumented stair using their self-selected and forward trunk lean postures. Three-dimensional kinematics (200 Hz) and kinetics (2000 Hz) were recorded during the stance phase of stair ascent. Biomechanical dependent variables were calculated during the stance phase of stair ascent and included peak forward trunk lean, hip flexion, hip adduction, hip internal rotation angles, and the average hip extensor moment.Results: During the forward trunk lean condition, decreases were observed for peak hip adduction (MD = 2.8˚; 95% CI = 1.9, 3.8; p < 0.001) and peak hip internal rotation (MD = 1.1˚; 95% CI = 0.1, 2.2; p = 0.04). In contrast, increases were observed during the forward trunk lean condition for the peak forward trunk lean angle (MD = -34.7˚; 95% CI = -39.1, -30.3; p < 0.001), average hip extensor moment (MD = -0.5 N·m/kg; 95% CI = -0.5, -0.4; p < 0.001), and stance time duration (MD = -0.02 s; 95% CI = -0.04, 0.00; p = 0.017).Significance: Increasing forward trunk lean and hip extensor use during stair ascent decreased peak hip adduction and internal rotation in asymptomatic females. Future studies should examine the effects of increasing forward trunk lean on hip kinematics, self-reported pain, and function in individuals with patellofemoral pain. [ABSTRACT FROM AUTHOR]

Gonçalves, BM, Mesquita, RNO, Tavares, F, Brito, J, Correia, P, Santos, P, and Mil-Homens, P. A new portable device to reliably measure maximal strength and rate of force development of hip adduction and abduction. J Strength Cond Res 36(9): 2465–2471, 2022—Groin injuries are a major issue in sports involving kicking or quick changes of direction. Decreased hip adduction and abduction strength have been indicated as one of the main risk factors for groin injury. The methods currently available to measure hip adduction and abduction strength are reliable but highly dependent on the evaluator skills. Furthermore, several studies have reported the reliability of maximal strength (MVIC), but very few studies investigated the reliability of explosive strength (RFD), a parameter that has been previously shown to have a higher functional value. The aim of the current investigation was to assess the reliability of a user-independent portable dynamometer that concurrently measures MVIC and RFD. Twenty-five healthy young subjects performed maximal isometric hip adduction and abduction in both sitting and supine positions. Measurements occurred in 2 different days separated by 48–72 hours. Test-retest reliability was calculated for both MVIC and RFD. Both MVIC and RFD showed good relative reliability (intraclass correlation coefficient = 0.77–0.98) with no differences between positions or muscle actions. Measurement error was similar between positions for MVIC in both hip adduction and abduction. Measurements of RFD showed higher reliability using a time window of at least 0–100 milliseconds, and lower measurement error was observed in sitting for adduction and in supine for abduction. This study shows that portable dynamometry can be used to concurrently measure hip adduction and abduction maximal and explosive strength, with levels of reliability that are similar to previously described methods. [ABSTRACT FROM AUTHOR]

Anomalous ocular muscle insertions are a rare cause of ocular motility disturbances. We report the clinical presentation and the intraoperative findings of two cases with an abnormally nasally inserted superior oblique tendons presenting with a Brown syndrome-like clinical picture. Case no 1 was a 5-year-old girl presenting with a chin up position. There was bilateral limitation of elevation in adduction, −4 on the right side and −3 on the left side with +1 downshoot on adduction on either side Patient was orthotropic in down-gaze with small V-pattern exotropia. Case no 2 was a 4-year-old boy presenting with an esotropia of 35Δ that was partially corrected with his spectacles to 20Δ. Ductions showed −4 defective elevation in adduction of the right eye. Surgical exploration in both cases revealed abnormal nasal insertion of the superior oblique tendons. The line of insertion had a convexity facing superonasally. The posterior fibers were inserted 7–8 mm posterior and just nasal to the nasal border of the superior rectus insertion, while the anterior fibers were shorter and inserted 5 mm nasal and 4 mm posterior to the nasal edge of superior rectus insertion. In both cases, there was an improvement in the elevation on adduction after superior oblique lengthening. Abnormal nasal insertion of the superior oblique muscle enhances the depressor effect of the muscle and can create a Brown-like picture. [ABSTRACT FROM AUTHOR]

This study investigated the effect of a handball-specific fatigue protocol on hip and knee kinematics. Twenty female handball athletes performed three trials of the single-leg landing (SLL), sidestep cutting manoeuvre (SCM), and drop vertical jump (DVJ) before and after the fatigue protocol. Knee and hip angle waveforms were compared using statistical parametric mapping (p < 0.05). During the SLL, the fatigue increased hip adduction (4–7% cycle) and knee abduction (4–9% and 25–27%). For the SCM, hip flexion was reduced under fatigue during 14–29% and 44–68% of the cycle. Similarly, the knee flexion decreased between 7–36% and 53–73%. Besides, during the fatigue state, the athletes reduced the hip abduction between 0–11% of the cycle and increased the knee abduction between 20–23%. During the DVJ task, when fatigued, the hip flexion decreased between 19–44% of the cycle and the knee flexion between 1–16% and 18–77%. The fatigue protocol altered the lower limb kinematics, decreasing knee and hip flexions during the SCM and DVJ and increasing the knee valgus during both single-leg landing tasks. [ABSTRACT FROM AUTHOR]

As the modern golf swing has changed, the incidence of knee pain in professional golfers is increasing. For those with previous knee injuries, developing a golf-swing modification that reduces knee loading may be necessary to recover performance after injury. The purpose of this study was to test whether ball position modification reduces knee joint load in a golf swing. Thirteen male professional golfers participated in the study. Golf swings were captured using a three-dimensional motion capture system and two force platforms, with conditions for self-selected ball position and eight additional ball positions. Knee internal rotation and adduction moments were calculated. The length of one golf ball (4.27 cm) backward ball position (closer to the golfer) significantly reduced the peak internal rotation moment of the lead knee (-13.8%) (p < 0.001) and the length of one golf ball (4.27 cm) away from the target ball position significantly reduced the peak adduction moment of the lead knee (-11.5%) (p < 0.001) compared with that of the self-selected ball position. Based on these observations, we conclude that the backward ball position modification might be suggested for golfers with anterior cruciate ligament injuries, and the away from the target modification might be suggested for golfers with medial compartment knee osteoarthritis. [ABSTRACT FROM AUTHOR]

The article aims to equip voice teachers with pedagogic techniques and exercises that parallel those used in speech pathology practices and to help voice teachers work in collaboration with voice clinicians, to rectify a vocal trend that has caused vocal damage to many of this generation's young singers. It focuses on helping voice teachers to address hyperadduction and muscle tension dysphonia. Mentions primary and secondary hyperadductive and vocal fatigue practices.

Background: Postoperative biomechanics after hip arthroscopy for femoroacetabular impingement syndrome (FAIS) are an outcome of interest, but correlation with patient-reported outcomes (PROs) remains unclear. Purpose/Hypothesis: The purpose of this study was to assess the correlation between changes in hip biomechanics in FAIS patients after hip arthroscopy and changes in PRO scores. We hypothesized that gait analysis would demonstrate significant correlations between pre- and postoperative changes in biomechanics and changes in PRO scores. Study Design: Descriptive laboratory study. Methods: FAIS patients without dysplasia or arthritis who underwent primary hip arthroscopy for labral repair and femoroplasty underwent preoperative and 1-year postoperative 3-dimensional motion tracking and biomechanical testing during normal gait. Joint kinematics calculated included flexion/extension (sagittal plane), abduction/adduction (frontal plane), and internal/external rotation (transverse plane). Peak hip angles and moments were compared between baseline and 1-year postoperative measures. At baseline, 1-year, and 2-year postoperatively, patients completed the following PRO surveys: 12-Item Short Form Health Survey (SF-12), modified Harris Hip Score (mHHS), and Hip disability and Osteoarthritis Outcome Score (HOOS). Joint kinematics that significantly improved 1 year after surgery were assessed for correlations with PRO scores. Results: A total of 10 patients (12 hips) were enrolled prospectively. PROs significantly improved at 1 and 2 years postoperatively compared with baseline values for HOOS, mHHS, and SF-12 Physical Component Score, with all patients achieving the minimal clinically important difference (MCID) on the HOOS Sport/Recreation and Quality of Life subscales. From preoperatively to 1-year postoperatively, significant improvements were seen in peak hip abduction angle (from −2.3° ± 1.8° to −4.6° ± 1.8°; P =.0058) and peak hip extension moment (from −1.03 ± 0.19 to −0.85 ± 0.20 N·m/kg; P =.014); however, there were no significant correlations between these changes and the pre- to postoperative changes on any PRO scores. Conclusion: Gait analysis of FAIS patients after hip arthroscopy demonstrated small, albeit significant, changes in postoperative hip kinetics and kinematics; however, these changes did not correlate with the large, clinically significant improvements in PROs at 1 year after surgery. Clinical Relevance: The results of this study suggest that the degree of improvement in short-term PROs after hip arthroscopy for FAIS may not be related to small changes in biomechanics postoperatively. [ABSTRACT FROM AUTHOR]

OBJECTIVES: To (1) evaluate an injury risk model that included modifiable and nonmodifiable factors into an arm injury risk prediction model in Minor League Baseball (MiLB) pitchers and (2) compare model performance separately for predicting the incidence of elbow and shoulder injuries. DESIGN: Prospective cohort. METHODS: A 10-year MiLB injury risk study was conducted. Pitchers were evaluated during preseason, and pitches and arm injuries were documented prospectively. Nonmodifiable variables included arm injury history, professional experience, arm dominance, year, and humeral torsion. Modifiable variables included BMI, pitch count, total range of motion, and horizontal adduction. We compared modifiable, nonmodifiable, and combined model performance by R², calibration (best = 1.00), and discrimination (area under the curve [AUC]; higher number is better). Sensitivity analysis included only arm injuries sustained in the first 90 days. RESULTS: In this study, 407 MiLB pitchers (141 arm injuries) were included. Arm injury incidence was 0.27 injuries per 1000 pitches. The arm injury model (calibration 1.05 [0.81-1.30]; AUC: 0.74 [0.69-0.80]) had improved performance compared to only using modifiable predictors (calibration: 0.91 [0.68-1.14]; AUC: 0.67 [0.62-0.73]) and only shoulder range of motion (calibration: 0.52 [0.29, 0.75]; AUC: 0.52 [0.46, 58]). Elbow injury model demonstrated improved performance (calibration: 1.03 [0.76-1.33]; AUC: 0.76 [0.69-0.83]) compared to the shoulder injury model (calibration: 0.46 [0.22-0.69]; AUC: 0.62 [95% CI: 0.55, 0.69]). The sensitivity analysis demonstrated improved model performance compared to the arm injury model. CONCLUSION: Arm injury risk is influenced by modifiable and nonmodifiable risk factors. The most accurate way to identify professional pitchers who are at risk for arm injury is to use a model that includes modifiable and nonmodifiable risk factors. [ABSTRACT FROM AUTHOR]

Aims: Cam and pincer morphologies are potential precursors to hip osteoarthritis and important contributors to non-arthritic hip pain. However, only some hips with these pathomorphologies develop symptoms and joint degeneration, and it is not clear why. Anterior impingement between the femoral head-neck contour and acetabular rim in positions of hip flexion combined with rotation is a proposed pathomechanism in these hips, but this has not been studied in active postures. Our aim was to assess the anterior impingement pathomechanism in both active and passive postures with high hip flexion that are thought to provoke impingement. Methods: We recruited nine participants with cam and/or pincer morphologies and with pain, 13 participants with cam and/or pincer morphologies and without pain, and 11 controls from a population-based cohort. We scanned hips in active squatting and passive sitting flexion, adduction, and internal rotation using open MRI and quantified anterior femoroacetabular clearance using the β angle. Results: In squatting, we found significantly decreased anterior femoroacetabular clearance in painful hips with cam and/or pincer morphologies (mean -11.3° (SD 19.2°)) compared to pain-free hips with cam and/or pincer morphologies (mean 8.5° (SD 14.6°); p = 0.022) and controls (mean 18.6° (SD 8.5°); p < 0.001). In sitting flexion, adduction, and internal rotation, we found significantly decreased anterior clearance in both painful (mean -15.2° (SD 15.3°); p = 0.002) and painfree hips (mean -4.7° (SD 13°); p = 0.010) with cam and/pincer morphologies compared to the controls (mean 7.1° (SD 5.9°)). Conclusion: Our results support the anterior femoroacetabular impingement pathomechanism in hips with cam and/or pincer morphologies and highlight the effect of posture on this pathomechanism. Cite this article: Bone Jt Open 2021;2(11):988–996.

Aims: In the native hip, the hip capsular ligaments tighten at the limits of range of hip motion and may provide a passive stabilizing force to protect the hip against edge loading. In this study we quantified the stabilizing force vectors generated by capsular ligaments at extreme range of motion (ROM), and examined their ability to prevent edge loading. Methods: Torque-rotation curves were obtained from nine cadaveric hips to define the rotational restraint contributions of the capsular ligaments in 36 positions. A ligament model was developed to determine the line-of-action and effective moment arms of the medial/lateral iliofemoral, ischiofemoral, and pubofemoral ligaments in all positions. The functioning ligament forces and stiffness were determined at 5 Nm rotational restraint. In each position, the contribution of engaged capsular ligaments to the joint reaction force was used to evaluate the net force vector generated by the capsule. Results: The medial and lateral arms of the iliofemoral ligament generated the highest inbound force vector in positions combining extension and adduction providing anterior stability. The ischiofemoral ligament generated the highest inbound force in flexion with adduction and internal rotation (FADIR), reducing the risk of posterior dislocation. In this position the hip joint reaction force moved 0.8° inbound per Nm of internal capsular restraint, preventing edge loading. Conclusion: The capsular ligaments contribute to keep the joint force vector inbound from the edge of the acetabulum at extreme ROM. Preservation and appropriate tensioning of these structures following any type of hip surgery may be crucial to minimizing complications related to joint instability. Cite this article: Bone Joint Res 2021;10(9):594–601.

The measurement point of chest shape based on non-rigorous ergonomics is the key problem affecting the accuracy of measurement results. Xiphoid point, as a representative human skeleton point, can provide a theoretical basis for the development of new chest shape measurement methods and technology. In order to verify the stability of xiphoid point, 30 subjects were selected to measure the chest shape based on upper limb movement in the transverse plane of human body. The displacement of mastoid and xiphoid points in the sagittal plane, coronal plane, and axial plane was compared, and the factors influencing the displacement of mastoid and xiphoid points were analyzed. The results showed that the displacement of the mammary point was the largest in the coronal plane during the upper limb movement. The displacement of xiphoid point is far less than that of mastoid point. The displacement of the breast point is closely related to the chest circumference when the upper limb is in the horizontal adduction. There was a positive correlation between the displacement of xiphoid point and the amplitude of upper limb movement. Compared with mammary point, xiphoid point is a fixed and stable measurement point of chest shape. [ABSTRACT FROM AUTHOR]

In order to assist patients with finger rehabilitation training and grasping objects, we propose a new type of soft rehabilitation gloves (SRGs), which has both flexion/extension and abduction/adduction movement function for every finger. This paper describes the structure design of the bending actuator and rotating actuator, the fabrication process of the soft actuator, and the implementation of the soft wearable gloves based on a fabric glove. FEM simulation analysis and experiments were conducted to characterize the mechanical behavior and performance of the soft glove in terms of the angle output and force output upon pressurization. To operate this soft wearable glove, we designed the hardware system for SRGs with a flexible strain sensor and force sensor in the loop and introduced a force/position hybrid PID control algorithm to regulate the pressure inputted. Experiment evaluation focused on rehabilitation training gestures; motions and the precise grasping assistance function were executed. The rotating actuator between each finger can supply abduction/adduction motion manner for patients, which will improve rehabilitation effect. The experimental results demonstrated that the developed SRGs have the potential to improve hand movement freedom and the range of grasping successfully. [ABSTRACT FROM AUTHOR]

Supplemental digital content is available in the text. Objective: This study aimed to investigate the effects of a 6-wk proprioceptive neuromuscular facilitation stretching on pain, proprioception, joint range of motion, and joint moments during stair ascending among older adults with knee osteoarthritis. Design: This study is a randomized, controlled, and assessor-blinded trial. Thirty-six older adults with knee osteoarthritis were randomly assigned to the proprioceptive neuromuscular facilitation and the control groups. They received proprioceptive neuromuscular facilitation stretching and health lecture series, respectively, for 6 wks. Final data analysis included 14 participants of the proprioceptive neuromuscular facilitation group and 13 of the control group. Pain score, joint proprioception, range of motion, and joint moments during stair ascending were measured before and after the stretching. Two-way (group by time) analysis of variance with repeated measures was used to evaluate stretching effects. Results: Significant interactions were detected in pain score, joint proprioception, external knee adduction moment, and external knee extension moment. Compared with week 0, the pain score, joint proprioception threshold, and external knee adduction moment decreased, whereas the external knee extension moment increased among older adults in the proprioceptive neuromuscular facilitation group at week 7. Conclusions: Proprioceptive neuromuscular facilitation could be recommended as one of the clinical treatments for knee osteoarthritis to relieve pain, improve proprioception, and balance load distribution between medial and lateral compartments at the knee. [ABSTRACT FROM AUTHOR]

How to use few actuators to endow a multifingered robotic hand with the human grasping and manipulation abilities is a challenging problem. This article develops a design principle of a five-fingered robotic hand with only two actuators, which guarantees the designed hand can replicate a large portion of the grasping and a limited portion of the manipulation abilities of the human hand: simultaneously move all joints before contacting objects like the natural reach-to-grasp process of the human hand; self-adaptively pinch/envelop objects with arbitrary shapes; and carry out dexterous manipulation, such as in-hand manipulation of a ball and screwing bottle cap. The core design ideas involve two levels. The higher level idea is to construct a robotic design theory ensuring thumb and fingers driven independently and four fingers driven synergistically so that the opposable thumb with manual abduction/adduction function can move coordinately with four fingers to ensure abundant anthropomorphic grasps and in-hand manipulations. The lower level idea is to establish a mechanism design method that embeds human two primary eigengrasps into a novel single-actuated differential palm mechanism consisting of gears, drag axes, and slider elements, so that the mechanism can always replicate the grasping behaviors of human hand, no matter how the differential processes it would perform during grasping. Finally, we design a mini X-hand to verify our proposed design principle and reproduce 29 types out of 33 grasping types and some manipulations that are commonly used by human hands in daily life. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a common type of arthritis, affecting millions of people around the world. Angiopoietin-2 (Angpt-2) has a role in the development of chronic inflammatory diseases. We aimed to assess the serum Angpt-2 levels in knee OA patients and to investigate the association of Angpt-2 gene polymorphism(rs3020221 C/T) with knee OA susceptibility and severity. Angiopoietin-2(rs3020221C/T) gene polymorphism was identified in 254 knee OA patients and 227 healthy controls using real-time polymerase chain reaction. Serum Angpt-2 was measured using ELISA. The Arabic version of the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index and Kellgren-Lawrence (KL) grading score were used to assess the clinical and radiological severity of OA and their relationship with Angpt-2(rs3020221C/T) gene polymorphism was investigated. Serum Angpt-2 levels were significantly higher in knee OA patients than in the controls (P =.001). OA patients with C/T genotype had a four times greater risk of developing OA than other genotypes (OR = 4.39, 95% CI = 2.85–6.76). Additionally, the T allele presented more in OA patients 224/508 (44%) with two times risk of developing OA (OR = 1.86, 95% CI = 1.43–2.43, p =.001). Angpt-2 SNP (rs3020221C/T) genotype C/T was significantly associated with elevated serum Angpt-2 levels (14.15 ± 5.62 ng/ml). The serum Angpt-2 levels are significantly elevated in OA patients and Angpt-2 gene polymorphism (rs3020221 C/T) may be a risk factor for OA development and both are associated with the severity of knee OA. Carriers of the C/T genotype have a significantly higher serum Angpt-2 levels and a greater risk of developing OA. [ABSTRACT FROM AUTHOR]

Nine months after anterior cruciate ligament (ACL) reconstruction, athletes who undergo surgery using a bone‐patellar‐tendon‐bone (BPTB) autograft demonstrate higher loading asymmetries during vertical jumping than those with a hamstring tendon (HT) autograft. These asymmetries may transfer into sporting movements with a greater ACL injury risk. The aim of this study was to compare between‐limb asymmetries in knee mechanics and task performance during an unplanned 90° change‐of‐direction (CoD) task in male field sport athletes reconstructed with BPTB or HT autografts. Seventy‐eight male multidirectional field sport athletes with either a BPTB (n = 39) or HT (n = 39) autograft completed maximal unplanned CoD trials in a three‐dimensional motion capture laboratory at approximately 9 months post‐surgery. A mixed‐model 2x2 ANOVA (autograft type x limb) was used to compare variables related to ACL injury risk (e.g., internal knee moments) and performance (e.g., completion time) between autografts and limbs. Statistical parametric mapping was used for a waveform comparison throughout stance, supplemented with a discrete point analyses of peak knee moments and performance variables. Interaction effects were found at the knee joint, with BPTB demonstrating greater asymmetries than HT in knee extension moment (p < 0.001); resultant ground reaction force (p < 0.001); peak knee external rotation moment (p = 0.04); and knee adduction (p = 0.05), medial rotation (p < 0.001), and flexion (p < 0.001) angles. No differences were found between autografts for any performance variable. BPTB demonstrated greater lower‐limb biomechanical asymmetries than HT during CoD, which may influence knee loading and longer‐term outcomes and should thus be targeted during rehabilitation prior to return to play. [ABSTRACT FROM AUTHOR]

Objectives: For unilateral vocal fold paralysis (UVFP) with large posterior glottic gap medialization laryngoplasty (ML) + arytenoid adduction (AA), ML + adduction arytenopexy (AApexy), and ML alone using prosthesis with posterior extension are possible solutions. This study was carried out to elucidate the controversy among these solution options. Methods: Retrospective cohort. Tertiary referral center. One hundred forty patients with UVFP with large posterior glottic gap. Group 1 had 30 patients with ML + AA; Group 2 had 25 patients with ML + AApexy; Group 3 had 29 patients with ML using Isshiki prosthesis; Group 4 had 26 patients with ML using Montgomery prosthesis; Group 5 had 30 patients with ML using prosthesis with large posterior extension. Glottic closure using videolaryngostroboscopy, GRBAS, VHI-30, EAT-10, acoustic and aerodynamic analysis was carried out pre- and 1-year-postoperatively. Results: Preoperatively there was no significant difference in any parameters studied among all study groups (P >.05). Except F0, speaking F0 and EAT-10, all other parameters in acoustic and aerodynamic analysis, glottic closure, GRBAS, and VHI-30 scores were significantly better postoperatively in Groups 1 and 2 compared to Groups 3 to 5 (P <.05). Conclusions: In patients with UVFP and large posterior glottic gap, ML + AA and ML + AApexy seem to do better subjectively and objectively, acoustically and aerodynamically, when compared to ML using prosthesis with and without large posterior extension. ML alone does not appear to close posterior glottic gap. Therefore, it is a better and more reasonable option to perform arytenoid procedure when there is large posterior glottic gap in UVFP. [ABSTRACT FROM AUTHOR]

Purpose: To compare the postoperative eye alignment in patients who underwent bilateral medial rectus advancement with those who underwent unilateral medial rectus advancement plus ipsilateral lateral rectus recession in the case of large angle consecutive exotropia without adduction deficit. Methods: Thirty-four patients with large angle consecutive exotropia that developed after infantile esotropia surgery were included in this retrospective study. Nineteen patients underwent bilateral medial rectus muscle advancement (group I) and 15 underwent unilateral medial rectus muscle advancement with ipsilateral lateral rectus muscle recession (group II). The follow-up periods were at least 12 months. Postoperative eye alignment was assessed and orthotropia within 10 prism diopters was considered a successful result. Results: The mean age of patients was 9.45± 2.71 years in group I and 9.93± 2.05 years in group II. Sixty percent of patients were female in group II and 57.89% in group I. In group I, the mean preoperative angle of deviation was 56.26± 3.78 PD at distance and 53.11± 3.49 PD at near. In group II, patients had a mean preoperative angle of deviation of 56± 3.38 and 52.47± 2.77 PD at distance and near, respectively. At the end of the follow-up period, the success rate was 52.63% in group I and 73.33% in group II (p = 0.22). The mean of the dose-effect relationship in group I was 2.62± 1.35 PD/mm while in group II it was 2.36± 0.84 PD/mm (p = 0.52). Conclusion: In patients with large angle consecutive exotropia, unilateral medial rectus advancement combined with ipsilateral lateral rectus recession produced better postoperative eye alignment than bilateral medial rectus advancement. Group I had a higher dose-effect relationship than group II. [ABSTRACT FROM AUTHOR]

In this work, an attempt has been made to analyze the influence of pathological changes in eye globe dimensions towards the mechanical responses of optic nerve head tissues during eye adductions. For this study, a 3D baseline model geometry of posterior ocular tissues has been constructed. The eye globe diameters of the model are modified to mimic the changes in ocular globe morphology in control, glaucoma, myopia and glaucoma with myopia conditions. Adductions are simulated for each modified model as the rotation of the globe from 1o to 10o in steps of 1o. von Mises strain in lamina cribrosa (LC) and posterior displacement of LC are estimated. Results show that strains developed in LC and its posterior displacement are higher in diseased eyes compared to healthy eyes. It appears that eyes with higher axial length and globe anisotropy are more susceptible to optic nerve head damage. This study might be extended to assess the progression of glaucomatous optic neuropathy. [ABSTRACT FROM AUTHOR]