Shoulder Abduction Research Articles

Influence of scapular motion cues on trapezius muscle activity during Y exercise.

The Y exercise is a therapeutic exercise facilitating lower trapezius muscle activity. To identify the effects of scapular movement cues (posterior tilt vs. posterior tilt with adduction/depression) on trapezius muscle activity during Y exercise. Fifteen healthy men without current shoulder pain performed general Y exercise; Y exercise with cues for scapular posterior tilt; and Y exercise with cues for scapular posterior tilt, adduction, and depression. Electromyography (EMG) data for the trapezius muscles were collected during Y exercise. The posterior tilt angle of the scapula was measured in the prone position with and without cues for scapular posterior tilt using an inclinometer application. The greatest lower trapezius muscle activity was observed during Y exercise with cues for scapular posterior tilt, while the greatest EMG activity of the upper trapezius was observed during Y exercise with cues for scapular posterior tilt, adduction, and depression (p< 0.05). Middle trapezius muscle activity did not significantly differ among the three Y exercise conditions (p= 0.175). Cues for scapular posterior tilt significantly increased the scapular posterior tilt angle in the prone shoulder abduction position (p= 0.007). Cues for scapular posterior tilt were most effective in facilitating lower trapezius muscle activity during Y exercise.

Anesthetic management of scapular Y-osteotomy using a combination of suprascapular nerve block and erector spinae plane block for Sprengel deformity associated with Klippel-Feil syndrome: a case report

BackgroundKlippel-Feil syndrome (KFS) occurs in 1/40,000 individuals and is characterized by cervical fusion. Thirty percent of patients with KFS present with Sprengel deformity, leading to orthopedic problems and limited shoulder abduction. No reports exist regarding anesthetic procedures for pediatric scapular osteotomies.Case presentationWe report a case of a 4-year-and-7-month-old boy (95.6 cm, 14.7 kg) who underwent left scapular osteotomy. At the age of 8 months, he also underwent a right lower lobectomy due to a congenital pulmonary airway malformation. We decided to use a combination of suprascapular nerve block (SSNB), erector spinae plane block (ESPB), and general anesthesia. He received regular acetaminophen administration and fentanyl 5–10 μg/hour intravenously until 20 h postoperatively and remained on ≤ 2/10 in the Wong-Baker Face Scale (0: no hurt; 10: hurts worst).ConclusionThe combination of SSNB and ESPB could be an option for perioperative analgesia for scapular osteotomies.

Effect of physical therapy and modalities on frozen shoulder patients at Baptist Hospital Batu: a retrospective study

Introduction: Frozen shoulder was one of top 10 diseases with frequent visits at Baptist Hospital’s rehabilitation clinic in 2020. Treatment for this condition includes physical therapy and modalities. This study aims to compare the range of motion and pain scale before and after treatments on frozen shoulder patients in Baptist Hospital Batu. Material and Methods: This is a retrospective study using the data from medical records of patients known to have frozen shoulder who came to outpatient physical rehabilitation clinic at Baptist Hospital, Batu, for at least a month period of treatment. The parameters used are range of motions after interventions, pain scale using VAS, sex, and age. Result: Twenty-two patients were diagnosed with frozen shoulder, 16 patients were included in further analyses, 9 of 16 were women, and the most common age presentation was between 50-60 years. There were improvements in 12 patients being recorded for their shoulder flexion and abduction. The flexion ROM increased from 115 to 156 degrees, while abduction ROM increased from 95 to 144 degrees, on average. About 9 out of 13 patients had decreasing pain scale according to VAS, declining from 5.5 to 4.7. Conclusion: The combination of physical exercises as well as SWD / ultrasound with TENS (transcutaneous electrical nerve stimulation) has a positive impact on the improvement of frozen shoulder. There was an increase in the range of motion of the joint flexion and abduction, and a decrease in pain scores in the majority of the patients after treatment.

Selective upper trunk posterior division fascicular nerve transfer for proximal spinal accessory neuropathy: illustrative case.

Spinal accessory nerve palsy can lead to severe shoulder pain and weakness, lateral scapular winging, and limitations in overhead activity. It most often occurs because of iatrogenic injury from procedures within the posterior triangle of the neck. The authors present the case of a 39-year-old male with symptoms of right shoulder weakness and neck pain after a total thyroidectomy and right neck dissection. With ultrasound findings of a neuroma-in-continuity but no clinical or electromyographic signs of reinnervation at 6 months, surgical intervention was indicated. Operative exploration confirmed a very proximal injury and nonconducting neuroma-in-continuity of the spinal accessory nerve. A selective distal nerve transfer from the posterior division of the upper trunk was performed. At the 2.5-year follow-up, the patient demonstrated excellent recovery of full active shoulder abduction and forward flexion, return to full-time employment, and mild residual scapular winging. Distal nerve transfers should be considered in cases of late presentation when primary repair is not possible or long interpositional grafts are required. Selective fascicular transfer from the posterior division of the upper trunk provides the advantages of a single incision, short reinnervation time, and synergistic donor function to facilitate motor reeducation.

Kinematic analysis of movement patterns during a reach-and-grasp task in stroke patients.

This study aimed to evaluate the kinematic movement patterns during a reach-and-grasp task in post-stroke patients according to the upper extremity impairment severity. Subacute stroke patients (n = 46) and healthy controls (n = 20) were enrolled in this study. Spatiotemporal and kinematic data were obtained through 3D motion analysis during the reach-and-grasp task. Stroke patients were grouped using the Fugl-Meyer Assessment (FMA) scale, and a comparison of the groups was performed. The severe group showed a significantly longer movement time, lower peak velocity, and higher number of movement units than the mild group during the reach-and-grasp task (p < 0.05). Characteristic compensatory movement patterns, such as shoulder abduction, thoracic posterior tilting, and upward and external rotation were significantly greater during the forward transporting phase in the severe group than in the mild group (p < 0.05). The FMA score was significantly associated with the movement time during the forward transporting phase, number of movement units during the reaching phase, range of shoulder abduction-adduction and wrist flexion-extension movements during the reaching phase, and range of thoracic internal-external rotation during the backward transporting phase (p < 0.05). Post-stroke patients have unique spatiotemporal and kinematic movement patterns during a reach-and grasp-task according to the impairment severity.

Relationship between throwing distance, shoulder joint range of motion, and upper limb muscle strength in boccia athletes

The purpose of this study was to examine the relationship between throwing distance, shoulder joint range of motion and upper limb muscle strength in boccia athletes. Participants were eight boccia athletes (cerebral palsy, cervical spinal cord injury, muscular dystrophy, spinal muscle atrophy) in whom throwing distance, ranges of motion at the shoulder joint, elbow joint and wrist joint and upper limb muscle strength were measured. Throwing distance was measured to the point where the ball landed so to remove any effect of the floor. Upper limb muscle strength was measured by isometric contraction using a handheld dynamometer. No correlation was found between throwing distance and range of motion of the shoulder joint, but correlations were found between throwing distance and strength of shoulder flexors (r = 0.76, p &lt; .05), shoulder abductors (r = 0.84, p &lt; .01), and elbow flexors (r = 0.77, p &lt; .05). Active training to improve muscle strength around the shoulder joint, regardless of the underlying disease, was considered likely to lead to improvements in competitiveness. Due to the severe dysfunction of boccia athletes, training methods are often restricted. Verification of more effective training methods is needed while managing risks according to the physical function of the athlete and the type of disability.

Feasibility and Efficacy of the Newly Developed Robotic Hybrid Assistive Limb Shoulder Exercises in Patients with C5 Palsy during the Acute Postoperative Phase.

Background and Objectives: Although postoperative C5 palsy is a frequent complication of cervical spine surgery, no effective therapeutic rehabilitation approach has been established for postoperative C5 palsy. The purpose of this study was to find evidence confirming the effectiveness and feasibility of robotic Hybrid Assistive Limb (HAL) shoulder exercises for C5 palsy. Materials and Methods: In this before-after, uncontrolled case series clinical study, we performed a mean of 11.7 shoulder training sessions using a shoulder HAL immediately after the onset of C5 palsy in seven shoulders of six patients who developed postoperative C5 palsy and had difficulty raising their shoulder during the acute postoperative phase of cervical spine surgery. Shoulder HAL training was introduced as early as possible after evaluating the general condition of all inpatients who developed C5 palsy. Patients underwent shoulder abduction training using shoulder HAL on an inpatient and outpatient basis at 2-week or 1-month intervals. Adverse events associated with shoulder HAL training were investigated. The shoulder abduction angle and power without the shoulder HAL were evaluated before shoulder HAL usage, at every subsequent session, and upon completion of all sessions. Results: Severe adverse events due to shoulder HAL training were not reported. After completion of all shoulder HAL sessions, all patients showed improved shoulder elevation, while shoulder abduction angle and power improved over time. Conclusions: Shoulder elevation training with HAL in patients in the acute stage of postoperative C5 palsy has the potential to demonstrate improvement in shoulder joint function with a low risk of developing severe adverse events.

Prespinal Versus Conventional Hemicontralateral C7 Nerve Transfer in the Treatment of Total Brachial Plexus Roots Avulsion Injuries: A Retrospective Study With a Minimum Follow-Up Period of 4 Years

Contralateral C7 (CC7)-to-median nerve transfer has been commonly used to restore hand function in brachial plexus injury. To shorten the nerve graft, the prespinal route was described and achieved direct coaptation when combined with humeral shortening osteotomy. The limb was positioned at 0° shoulder abduction and neutral head position. Given our concern about donor-site morbidity when harvesting the whole CC7 nerve and tension across the neurorrhaphy site after mobilization, we aimed to describe our modified prespinal route and compare its outcomes and complications with the conventional hemi-CC7 transfer. From 2004 to 2014, 39 patients with preganglionic total brachial plexus root avulsion injuries, with a minimum of 4 years of follow-up, were included. Overall, 20 and 19 patients underwent the conventional hemi-CC7-to-median nerve and hemi-CC7-to-lower trunk (LT) transfer through the modified prespinal route, respectively. The modified prespinal route was combined with bilateral clavicle shortening osteotomy to achieve direct coaptation to the LT at 45° shoulder abduction. The modified prespinal route showed the median period to achieve ≥M3 hand grip assessed in clinical follow-up was shorter (26.5 months vs 45.5 months), and a higher proportion of patients achieved ≥M3 hand grip recovery (63% vs 30%). One patient experienced symptomatic phrenic nerve injury; however, the hemidiaphragm fully recovered after 6 months. The long-term donor-site complication rate was 2.6%, including one sensory abnormality, and no permanent donor-site weakness after hemi-CC7 harvesting was observed. The modified prespinal route combined with clavicle osteotomy allowed direct coaptation to the LT and did not require head immobilization. It may allow a higher proportion of patients to achieve ≥M3 hand grip more quickly than conventional hemi-CC7 transfer. Therapeutic IV.

The effects of end-range interventions in the management of primary adhesive capsulitis of the shoulder: a systematic review and meta-analysis

Purpose To compare the effects of end-range manual therapy versus other conservative intervention on pain intensity, shoulder range of movement (ROM), and physical function in adhesive capsulitis (AC). Methods Two reviewers conducted a comprehensive search from inception to December 2022. PUBMED, Cochrane Library, CINAHL, EMBASE, and PEDro databases were searched. Clinical trials investigating the effects of end-range mobilisation techniques on pain, ROM, and physical function in patients with AC were included. Methodological quality was evaluated using the PEDro scale, and bias risk was assessed using the Cochrane Collaboration tool. GRADE was used to assess the certainty of the evidence. Data were presented using forest plots, and the random effects models were applied according to the Cochrane handbook. Results Ten randomised controlled trials were reviewed, involving 424 AC patients aged 20–70 years. Methodological quality of studies ranged from high to low. The end-range mobilisation showed improvements in pain intensity, shoulder abduction, internal rotation, and external rotation, and physical function compared to other conservative interventions in the short-and medium-terms. Certainty of the evidence was downgraded to very low. Conclusions Very low certainty evidence suggests that end-range mobilisation techniques improve pain intensity, shoulder ROM, and physical function in the short-and medium-term in AC.

Efficacy of Intra-articular Triamcinolone and Hyaluronic Acid in a Frozen Shoulder Rat Model.

Intra-articular corticosteroid or hyaluronic acid (HA) is commonly prescribed for frozen shoulder. However, few studies have investigated histological and molecular changes after injection. To compare the effectiveness of intra-articular injections of triamcinolone and HA in a frozen shoulder rat model and verify a greater effect of triamcinolone in passive shoulder abduction compared with HA. Controlled laboratory study. Twenty male Sprague-Dawley rats were randomly allocated into 4 groups (n = 5 in each): control group, which did not receive cast immobilization or injection, and 3 experimental groups, which received 3 weeks of unilateral shoulder immobilization followed by intra-articular injections (normal saline, triamcinolone, or HA) at the immobilized shoulder. Passive shoulder abduction angle, histological and immunohistochemical staining, and Western blotting results were assessed 2 weeks after injection. The intensity and extent of staining were converted to semiquantitative scores for further analysis. Shoulder abduction angles before sacrifice were 153.0°± 2.7° (control group), 107.0°± 5.7° (saline group), 139.0°± 9.6° (triamcinoline group), and 110.0°± 10.6° (HA group), showing significant differences between control and saline groups, control and HA groups, saline and triamcinoline groups, and triamcinoline and HA groups (P < .001) but not between control and triamcinoline groups (P = .053). Histologic evaluation revealed an increase in synovial folds and thickening of the capsular membrane in the saline and HA groups; this change was not evident in the triamcinolone group. A comparison of semiquantitative scores revealed greater expression levels of proteins involved in fibrosis and angiogenesis in the saline and HA groups compared with the control and triamcinolone groups. In Western blotting, the expression of inflammatory cytokines and the receptor for advanced glycation end products was significantly lower in the triamcinolone and HA groups than in the saline group. Triamcinolone injection was more effective than normal saline or HA injection in improving range of motion and reversing fibrotic and angiogenic features of frozen shoulder. Both triamcinolone and HA injections elicited anti-inflammatory effects. The antifibrotic and antiangiogenic properties of triamcinolone and the anti-inflammatory properties of both triamcinolone and HA should be considered when performing injections in clinical settings.

The use of the Classic and Modified Transfer of the Lower Trapezius Muscle (Elhassan Transfer) as a Primary or Secondary Method for Surgical Reconstruction of the Abduction and External Rotation of the Shoulder in Brachial Plexus Injury

Background. Brachial plexus injury (BPI) leads to severe dysfunction of the upper extremity (UE). Elbow flexion and multiaxial movements in glenohumeral joint (MGHJ) are prioritized in reconstruction strategy. Time-dependent (&lt; 6 months) nerve transfers (NT) allow effective restoring of MGHJ. Late (&gt; 6 months) reconstruction of MGHJ remains completely dependent on transfers of the functional tendon-muscle complexes.&#x0D; Objective: to compare the outcomes of the classic Elhassan (c) and modified (m) transfer of the lower trapezius muscle (LTT) on recovery of monoaxial MGHJ.&#x0D; Materials and Methods. Patient (P.) #3 with M4+ recovery of the deltoid muscle (DM) after NT and P. #4 without spontaneous recovery (SR) of DM – forward flexion (FF) was 170° and 0°, respectively, received cLTT. Patient #1 with M4+ recovery of DM after NT and P. #2 with M4+ SR of DM (FF was 160° and 50°, respectively), received mLTT – distal fixation point has been changed from the tendon of the infraspinatus to the tendon of supraspinatus muscle.&#x0D; Results. Shoulder abduction (ABD) has been restored to 50° in P. #1 and P. #2, while the recovery of the external rotation (ER) has not been achieved – upper arm remained internally rotated (IR). ABD has been restored to 40° and 80° in P. #3 and P. #4; simultaneously +15° and +70° of ER has been restored.&#x0D; Conclusions. The use of mLTT leads to more effective recovery of monoaxial MGHJ – ABD – 50° vs. 40° after cLTT. The use of cLTT leads to more effective recovery of another monoaxial MGHJ – ER – +15° and +70° vs. IR after mLTT; LTT should only be considered as a complementary surgical procedure, which utilization should cohere with a patient’s requirements to the MGHJ.

Initial effect of high-volume mobilisation with movement on shoulder range of motion and pain in patients with rotator cuff-related shoulder pain: protocol for a randomised controlled trial (Evolution Trial)

IntroductionMobilisation with movement (MWM) is commonly used for treating patients with rotator cuff-related shoulder pain (RCRSP). However, the evidence supporting MWM efficacy for improving shoulder range of motion (ROM) and...

Relative contributions of the supraspinatus cord and strap tendons to shoulder abduction and translation

The supraspinatus (SS) is formed by a larger anterior bipennate muscle with a cord like tendon and a posterior unipennate muscle with a strap like tendon. There is a tendinous connection between the two SS subunits. Yet, the relative mechanical contribution of the SS cord and SS strap muscular tendinous units to load transmission and subsequent shoulder abduction force is unknown. We hypothesized that a simulated SS cord versus a SS strap tear will generate less shoulder abduction force; and further, an intact SS cord will offset the expected abduction loss from a SS strap tear, but the inverse will not be true. Twenty fresh-frozen cadaveric specimens were tested in a shoulder simulator with physiological load vectors applied to the upper and lower subscapularis, SS cord, SS strap, infraspinatus, and teres minor. The roles of the SS cord and SS strap muscles were delineated by varying their loads, while keeping constant loads on other muscles. The randomized testing trials included a Native condition and four test Cases which simulated tears by dropping the load and force transfer via the SS cord-to-SS strap connection by adding the load. Testing was completed at both 0° and 30° of abduction. During each test shoulder abduction force, rotator cuff strains and humeral translation were measured. Simulated isolated SS cord and SS strap tears lead to a significantly lower shoulder abduction force (p<0.001). A simulated cord tear at 0° and 30° reduced the abduction force by 53% and 38%, respectively. A simulated strap tear at 0° and 30° dropped the abduction force by 27% and 23%, respectively. The decline in abduction force was larger for the SS cord tear versus SS strap tear (p≤0.001). A SS cord tear with full load transfer to the strap was able to recover to native values at both 0° and 30° (p≥0.288). Likewise, a SS strap tear with full load transfer to the SS cord showed a similar recovery to native values at both 0° and 30° (p≥0.155). During full load transfer, the tendon strain followed the loading pattern. A SS cord tear or SS strap tear did not cause a change in humeral translation (p≥0.303). A mechanical findings support the efficacy of nonoperative treatment of small (<10mm) SS tears,11 because an intact SS strap tendon can effectively offset the abduction loss of a torn SS cord tear, and vice versa.

Biomechanical changes, acceptance, and usability of a passive shoulder exoskeleton in manual material handling. A field study

Occupational exoskeletons contribute to diminish the biomechanical load during manual work. However, familiarization to the use of exoskeletons is rarely considered, which may lead to failure of acceptance and implementation. In this study, ten logistic workers underwent a 5-week progressive familiarization to a passive shoulder exoskeleton, while ten workers acted as controls. Tests pre and post the familiarization applied measurements of muscle activity and kinematics of back, neck, and shoulder, perceived effort, and usability-ratings of the exoskeleton. Exoskeleton use resulted in lower muscle activity of anterior deltoid (13–39%) and upper trapezius (16–60%) and reduced perceived effort. Additionally, it induced an offset in shoulder flexion and abduction during resting position (8–10°). No conclusions on familiarization could be drawn due to low adherence to the protocol. However, the emotions of the workers towards using the exoskeleton decreased making it questionable whether the shoulder exoskeleton is suitable for use in the logistics sector.

Effects of error rates and target sizes on neck and shoulder biomechanical loads during augmented reality interactions

Augmented reality (AR) interactions have been associated with increased biomechanical loads on the neck and shoulders. To provide a better understanding of the factors that may impact such biomechanical loads, this repeated-measures laboratory study evaluated the effects of error rates and target sizes on neck and shoulder biomechanical loads during two standardized AR tasks (omni-directional pointing and cube placing). Twenty participants performed the two AR tasks with different error rates and target sizes. During the tasks, angles, moments, and muscle activity in the neck and shoulders were measured. The results showed that the target sizes and error rates significantly affected angles, moments, and muscle activity in the neck and shoulder regions. Specifically, the presence of errors increased neck extension, shoulder flexion angles and associated moments. Muscle activity in the neck (splenius capitis) and shoulder (anterior and medial deltoids) also increased when the errors were introduced. Moreover, interacting with larger targets resulted in greater neck extension moments and shoulder abduction angles along with higher muscle activity in the splenius capitis and upper trapezius muscles. These findings indicate the importance of reducing errors and incorporating appropriate target sizes in the AR interfaces to minimize risks of musculoskeletal discomfort and injuries in the neck and shoulders.

Stemless reverse humeral component neck-shaft angle has an influence on initial fixation

Stemless anatomic humeral components are commonly used and are an accepted alternative to traditional stemmed implants in patients with good bone quality. Presently, little literature exists on the design and implantation parameters that influence primary time-zero fixation of stemless reverse humeral implants. Accordingly, this finite element analysis study assessed the surgical implantation variable of neck shaft angle, and its effect on the primary time-zero fixation of reversed stemless humeral implants. Eight CT-derived humeral finite element models were used to examine a generic stemless humeral implant at varying neck shaft angles of 130°, 135°, 140°, 145°, and 150°. Four loading scenarios [30° shoulder abduction with neutral forearm rotation, 30° shoulder abduction with forearm supination, a head-height lifting motion, and a single-arm steering motion] were employed. Implantation inclinations were compared based on the maximum bone-implant interface distraction detected after loading. The implant-bone distraction was greatest in the 130° neck shaft angle implantation cases. All implant loading scenarios elicited significantly lower micromotion magnitudes when neck shaft angle was increased (P = 0.0001). With every 5° increase in neck shaft angle, there was an average 17% reduction in bone-implant distraction. The neck shaft angle of implantation for a stemless reverse humeral component is a modifiable parameter that appears to influence time zero implant stability. Lower, more varus, neck shaft angles increase bone-implant distractions with simulated activities of daily living. It is therefore suggested that humeral head osteotomies at a higher neck shaft angle may be beneficial to maximize stemless humeral component stability.

Shoulder structures and strength in competitive preadolescent swimmers: A longitudinal ultrasonographic study.

Repetitive shoulder movements during competitive training may cause changes in the strength of periarticular shoulder structures in preadolescent swimmers. To prospectively determine the effects of training on shoulder periarticular structures and muscle strength in preadolescent swimmers. Prospective cohort study. Community-based natatorium. Twenty-four preadolescent swimmers aged 10-12 years. Not applicable. Measurements were repeated in three periods as preseason, midseason, and postseason. Ultrasonographic measurements (supraspinatus tendon thickness, humeral head cartilage thickness, deltoid muscle thickness, and acromiohumeral distance) were performed using a portable device and a linear probe. Shoulder (flexion, extension, abduction, internal and external rotation) and back (serratus anterior, lower, and middle trapezius) isometric muscle strength were measured with a handheld dynamometer. Supraspinatus tendon thickness and acromiohumeral distance were similar in all periods (all p > .05); however, deltoid muscle and humeral head cartilage thicknesses increased throughout the season (p = .002, p = .008, respectively). Likewise, whereas shoulder muscle strength increased (all p < .05), back muscle strength was similar in all periods (all p > .05). In preadolescent swimmers, acromiohumeral distance and supraspinatus tendon thickness seem to not change; but humeral head cartilage and deltoid muscle thicknesses as well as shoulder muscle strength increase throughout the season.

Limb-sparing resection of axillary soft tissue sarcomas

For patients with soft tissue sarcoma, surgical resection is akey element of curative therapy. Surgery is performed as awide resection with microscopically negative margins (R0resection) and as limb-sparing procedure whenever possible to preserve maximum function. Soft tissue sarcoma, metastases. Extensive disease with major neurovascular involvement, placement of biopsy tract necessitates extensive resection, palliative care. Extended deltopectoral approach. Release of pectoralis major and minor tendons. Vascular and neurologic exploration, identification of the axillary vessels and brachial plexus, placing of loops around major structures. Mobilization of these structures to achieve adequate exposure. Clipping of vessels entering the tumor. Tumor resection, suture marking for histological analysis. Soft tissue reconstruction by transosseous reinsertion of the pectoralis minor to the coracoid process. Drill channel placement, transosseous refixation of the pectoralis major to the humerus. Shoulder abduction brace for 6weeks, passive mobilization for 6-12weeks followed by active mobilization. Compression sleeve. Oncological follow-up. Between 2017 and 2022, wide resection was performed in 6consecutive cases including 4 primary soft tissue sarcomas and 2metastases. Primary R0 resection was achieved in 100%. Mean follow-up was 22.5months (3-60months). There were no local recurrences. Mean active shoulder abduction was 135.0 ± 41.4° (90-180°). Neurological deficits were not observed. Mean subjective shoulder function was 80.0 ± 21.0% (50-100%). The mean Musculoskeletal Tumor Society (MSTS) score was 89.5% (32-100%), indicating good functional outcome in the study cohort.

Measurement of Shoulder Abduction Angle with Posture Estimation Artificial Intelligence Model.

Substantial advancements in markerless motion capture accuracy exist, but discrepancies persist when measuring joint angles compared to those taken with a goniometer. This study integrates machine learning techniques with markerless motion capture, with an aim to enhance this accuracy. Two artificial intelligence-based libraries-MediaPipe and LightGBM-were employed in executing markerless motion capture and shoulder abduction angle estimation. The motion of ten healthy volunteers was captured using smartphone cameras with right shoulder abduction angles ranging from 10° to 160°. The cameras were set diagonally at 45°, 30°, 15°, 0°, -15°, or -30° relative to the participant situated at a distance of 3 m. To estimate the abduction angle, machine learning models were developed considering the angle data from the goniometer as the ground truth. The model performance was evaluated using the coefficient of determination R2 and mean absolute percentage error, which were 0.988 and 1.539%, respectively, for the trained model. This approach could estimate the shoulder abduction angle, even if the camera was positioned diagonally with respect to the object. Thus, the proposed models can be utilized for the real-time estimation of shoulder motion during rehabilitation or sports motion.

Do kinematic measures, added to clinical measures, better predict upper extremity motor impairments at three months post-stroke?

ObjectivePredicting post-stroke recovery through prediction models is crucial for choosing appropriate treatment options. However, the existing models predominantly incorporate clinical measures although measurement of movement quality using kinematic measures is essential for distinguishing various types of recovery. Thus, this study aimed at determining if, by considering varied aspects of recovery, adding kinematic measurements over clinical measures would better predict upper extremity (UE) motor impairments at three months post-stroke. Materials and methodsEighty-nine stroke survivors (58.9 ± 11.8 years) were assessed for clinical predictors between 4 and 7 days, kinematic predictors within 1 month, and the impairment outcome of the Fugl Meyer Assessment of the UE (FM-UE) at three months post-stroke. Significant predictors (p<0.05) with a variation inflation factor (VIF) <10 were selected for model development. After performing further step-wise selection, three models incorporating clinical outcomes, kinematic measurements, and a combination of these two, respectively, were formulated. ResultsThe clinical model (R2 = 0.70) included shoulder abduction finger extension (SAFE) scores, the National Institutes of Health Stroke Scale (NIHSS), and the Montreal Cognitive Assessment (MoCA). The kinematic model (R2 = 0.34) included total displacement, total time, and reaction time. The combined model (R2 = 0.72) comprised of SAFE score and shoulder flexion. All the models had a minimal mean squared error on cross validation, which indicated a good validity. ConclusionThe performance of clinical and combined prediction models for predicting three-month post-stroke UE motor recovery was nearly similar. However, in order to detect minimal changes over time and to understand all aspects of motor recovery, there is a need to add instrument-based kinematic measures.