Two synergistic types of muscles were detected during forearm rotation exercise by T2 cumulative frequency curves using 0.2 T magnetic resonance imaging.

The purpose of this study was the detection and characterization of synergistic muscle activity. Using T2-map MRI, T2 values for 10 forearm muscles in 11 healthy adult volunteers were obtained in the resting state and after isotonic forearm supination and pronation exercises with the elbow extended. T2 was normalized by Z = (T2e-T2r)/SDr, where T2e was T2 after exercise, while T2r and SDr were the reference values of 34 ms and 3 ms, respectively. Using the cumulative frequency curves of Z values (CFZ), we detected 2 and 3 synergistic muscles for supination and pronation, respectively, and divided these into 2 types, one activated by exercise strength dependently, and the other, independent of exercise strength, activated by only a smaller fraction of the participants. We also detected co-contraction for the supination. Thus, CFZ is a useful visualization tool to detect and characterize not only synergistic muscle, but also co-contraction muscle.

Lateral Femoral Condyle Allograft in the Treatment of Elbow Capitellar Avascular Necrosis: A Case Report.

CASE: A 27-year-old woman developed capitellar osteonecrosis after long-term corticosteroid use to treat non-Hodgkin lymphoma. She underwent an osteochondral reconstruction using a lateral femoral condyle (LFC) allograft. This graft was selected because it has a similar radius of curvature to the capitellum. The patient had osseous integration, painless, near full range of motion of her elbow 6 months postoperatively and good shoulder function 1.0 year postoperatively. CONCLUSION: The LFC allograft should be considered a viable option in treating capitellar osteonecrosis.

[A multicenter clinical study on the treatment of lateral epicondylitis of humerus by manipulation].

OBJECTIVE: To investigate clinical effect of tendons pulling,poking and kneading for the treatment of external humeral epicondylitis. METHODS: From January 2018 to December 2021,a multicenter randomized controlled study was performed to collect 192 patients with external humeral epicondylitis in Wangjing Hospital,Beijing Dianli Hospital,and Beijing Fengsheng Osteotraumatology Hospital,respectively,and they were divided into treatment group and control group by random number table method. There were 96 patients in treatment group,including 36 males and 60 females,aged from 28 to 60 years old with an average of (41.20±5.50) years old;the course of disease ranged from 1 to 14 days with an average of (5.24±1.35) days;they were treated once every other day for 2 weeks. There were 96 patients in control group ,including 33 males and 63 females,aged from 26 to 60 years old with an average of (43.35±7.75) years old;the course of disease ranged from 1 to 14 days with an average of (5.86±1.48) days;they were treated with topical voltaalin combined with elbow joint fixation for 2 weeks. Visual analogue scale (VAS) and Hospital for Surgery Scoring System (HSS) elbow pronation and supination angles,wrist metacarpal flexion and dorsal extension angles,elbow tenderness between two groups were compared before treatment and at 1,3,5,7,11 and 13 days after treatment;Hospital for Surgery Scoring System 2 (HSS2) was compared before treatment and the final treatment. RESULTS: All patients were followed up for 10 to 14 days with an average of (12±1.6) days. VAS between treatment group and control group before treatment were 6.83±1.36 and 6.79±1.58,respectively,and decreased to 1.49±1.09 and 2.11±1.81 after the final treatment. VAS of treatment group were significantly lower than those of control group at 1,3,5,7,9,11 and 13 days after treatment (P<0.05). HSS between two groups were 61.73±11.00 and 36.47±12.45 before treatment,respectively,and increased to 94.42±5.9 and 91.44±9.11 at the final treatment. HSS of treatment group were significantly higher than those of control group at 1,3,5,7,9,11 and 13 days after treatment (P<0.05). On the 5th day after treatment,the external and internal rotation angles of elbow in treatment group were (66.41±12.69) ° and (66.35±13.54) °,while those in control group were (62.08±16.03) ° and (61.77±16.35) °. On the 7th day after treatment,the external and internal rotation angles of elbow were (69.79±12.64) ° and (70.02±13.55) ° in treatment group,and (65.28±15.86) ° and (65.09±16.67) ° in control group. Elbow joint motion in treatment group was higher than that in control group (P<0.05). On the 5th day after treatment,angles of wrist dorsiflexion and palm flexion were (39.43±15.94) ° and (46.68±11.10) ° in treatment group,and (38.51±18.49) ° and (44.27±13.58) ° in control group. On the 7th day after treatment,angles of wrist dorsiflexion and palm flexion were (42.52±16.50) ° and (49.23±10.96) ° in treatment group,and (41.18±20.09) ° and (46.64±14.63) ° in control group. The motion of wrist joint in treatment group was higher than that in control group (P<0.05). On the 13th day after treatment,HSS2 in treatment group 93.61±6.32 were higher than those in control group 92.06±7.94(P<0.05). There was no significant difference in elbow tenderness between two groups at each time point (P>0.05). CONCLUSION: Voltaren external treatment combined with elbow fixation and tendons pulling,poking and kneading could effectively improve symptoms of external humeral epicondylitis. Compared with voltaren external treatment,tendons pulling,poking and kneading has advantages of longer analgesic time and better elbow function recovery.

CT Arthrography of the Elbow: What Radiologists Should Know.

Computed tomography (CT) arthrography is a quickly available imaging modality to investigate elbow disorders. Its excellent spatial resolution enables the detection of subtle pathologic changes of intra-articular structures, which makes this technique extremely valuable in a joint with very tiny chondral layers and complex anatomy of articular capsule and ligaments. Radiation exposure has been widely decreased with the novel CT scanners, thereby increasing the indications of this examination. The main applications of CT arthrography of the elbow are the evaluation of capsule, ligaments, and osteochondral lesions in both the settings of acute trauma, degenerative changes, and chronic injury due to repeated microtrauma and overuse. In this review, we discuss the normal anatomic findings, technical tips for injection and image acquisition, and pathologic findings that can be encountered in CT arthrography of the elbow, shedding light on its role in the diagnosis and management of different orthopedic conditions. We aspire to offer a roadmap for the integration of elbow CT arthrography into routine clinical practice, fostering improved patient outcomes and a deeper understanding of elbow pathologies.

The efficacy of pediatric elbow radiographic guidance in diagnosis of lateral humeral condyle fracture.

Although lateral humeral condyle fracture is common, the incidence of missed diagnosis is very high. Delayed and missed diagnosis led to significant morbidities and loss of functions. We designed a pediatric elbow radiographic guidance aiming to improve the accuracy of diagnosis. This study was aimed to evaluate the efficacy of the radiographic guidance for the diagnosis of lateral condyle fracture. A cross-sectional study was conducted after defining the essential parameters as a guidance for assessing the pediatric elbow radiographs. We included medical students, emergency medicine, orthopedic, and radiology residents and fellows into this study. A questionnaire was used to evaluate the efficacy of the guidance. All participants underwent a pretest evaluation, followed by studying the guidance, and then finished a posttest evaluation. Baseline characteristics, diagnostic scores, and parameter evaluation scores were collected. The pretest and posttest scores were analyzed using paired t-test. Association between baseline characteristics and diagnostic scores were analyzed using multiple regression analysis. We included 177 participants. Average diagnostic score was significantly increased after using the guidance, from 12.2 ± 1.9 to 13.0 ± 1.7 (p < 0.0001). Medical students showed the most improvement, from 11.9 ± 1.9 to 13.1 ± 1.3 (p <0.001). All means of essential parameter evaluation scores were significantly improved in overall participants.The pediatric elbow radiographic guidance is useful for evaluation and diagnosis of lateral condyle fracture, especially for young physicians and trainees. Therefore, this should be recommended in routine medical education and general practice.

Free flap reconstruction of elbow soft tissue defects: Lessons learned from 15 years of experience.

BACKGROUND: The elbow is a complex joint that is vital for proper function of the upper extremity. Reconstruction of soft tissue defects over the joint space remains challenging, and outcomes following free tissue transfer remain underreported in the literature. The purpose of this analysis was to evaluate the rate of limb salvage, joint function, and clinical complications following microvascular free flap coverage of the elbow. METHODS: This retrospective case series utilized surgical logs of the senior authors (Stephen J Kovach and L Scott Levin) to identify patients who underwent microvascular free flap elbow reconstruction between January 2007 and December 2021. Patient demographics and medical history were collected from the medical chart. Operative notes were reviewed to determine the type of flap procedure performed. The achievement of definitive soft tissue coverage, joint function, and limb salvage status at 1 year was determined from postoperative visit notes. RESULTS: Twenty-one patients (14 male, 7 female, median age 43) underwent free tissue transfer for coverage of soft tissue defects of the elbow. The most common indication for free tissue transfer was traumatic elbow fracture with soft tissue loss (n = 12, [57%]). Among the 21 free flaps performed, 71% (n = 15) were anterolateral thigh flaps, 14% (n = 3) were latissimus dorsi flaps, and 5% (n = 1) were transverse rectus abdominis flaps. The mean flap size was 107.5 cm2. Flap success was 100% (n = 21). The following postoperative wound complications were reported: surgical site infection (n = 1, [5%]); partial dehiscence (n = 5, [24%]); seroma (n = 2, [10%]); donor-site hematoma (n = 1, [5%]); and delayed wound healing (n = 5, [24%]). At 1 year, all 21 patients achieved limb salvage and definitive soft tissue coverage. Of the 17 patients with functional data available, 47% (n = 8) had regained at least 120 degrees of elbow flexion/extension. All patients had greater than 1 year of follow-up. CONCLUSION: Microvascular free flap reconstruction is a safe and effective method of providing definitive soft tissue coverage of elbow defects, as evidenced by high rates of limb salvage and functional recovery following reconstruction.

Comparison of decrease in elbow flexion strength in patients after tenotomy and tenodesis of the long head of the biceps brachii.

NTRODUCTION: The last two decades have been leading to the development of several types of surgical techniques and procedures to manage the LHB lesions. This paper analyses and compares the difference in muscle strength pre- and post-operatively in two most commonly used surgical procedures - LHB tenotomy and tenodesis. METHOD: The study includes 68 patients who underwent surgery between 2016 and 2020. The patients who had met the prospective study inclusion criteria were divided into two groups based on type of surgery they had undergone (LHB tenotomy or tenodesis); each group consisted of 34. The muscle strength during elbow flexion was measured preoperatively and postoperatively using the Commander Echo Console ultrasound muscle testing device. All patients enrolled in the study had been assessed for elbow flexion strength preoperatively. The muscle strength was measured preoperatively and then 3 years postoperatively (12 to 60 months) on average. CONCLUSION: The study confirmed that the patients who had undergone LHB tenodesis show a significantly lower decrease in elbow flexion strength and a significantly lower incidence of "Popeye" deformity than the patients after LHB tenotomy. Moreover, in the tenodesis group, it was possible to initiate rehabilitation earlier. The incidence of postoperative complications was almost identical in both groups of patients (Tab. 10, Fig. 6, Ref. 40).

Total Elbow Arthroplasty Historical and Current Concepts.

The evolution of total elbow arthroplasty (TEA) has laid the groundwork for modern day TEA and has contributed to our understanding of elbow biomechanics. Trends in the usage of TEA have also varied significantly over time. This article aims to review the history and evolution of the TEA implant with a focus on modern day implant biomechanics and the trends in TEA indications. Additionally, this review discusses various complications that can occur with modern day TEA and looks toward the future to identify innovation and future trends.

Upper limb motor dysfunction is associated with fragmented kinetics after brain injury.

BACKGROUND: Characterization of motor deficits after brain injury is important for rehabilitation personalization. While studies reported abnormalities in the kinematics of paretic and non-paretic elbow extension for patients with brain injuries, kinematic analysis is not sufficient to explore how patients deal with musculoskeletal redundancy and the energetic aspect of movement execution. Conversely, interarticular coordination and movement kinetics can reflect patients' motor strategies. This study investigates motor strategies of paretic and non-paretic upper limb after brain injury to highlight motor deficits or compensation strategies. METHODS: 26 brain-injured hemiplegic patients and 24 healthy controls performed active elbow extensions in the horizontal plane, with both upper limbs for patients and, with the dominant upper limb for controls. Elbow and shoulder kinematics, interarticular coordination, net joint kinetics were quantified. FINDINGS: Results show alterations in kinematics, and a strong correlation between elbow and shoulder angles, as well as time to reach elbow and shoulder peak angular velocity in both upper limbs of patients. Net joint kinetics were lower for paretic limb and highlighted a fragmented motor strategy with increased number of transitions between concentric and eccentric phases. INTERPRETATION: In complement to kinematic results, our kinetic results confirmed patients' difficulties to manage both spatially and temporally the joint degrees of freedom redundancy but revealed a fragmented compensatory motor strategy allowing patients upper limb extension despite quality alteration and decrease in energy efficiency. Motor rehabilitation should improve the management of this fragmentation strategy to improve the performance and the efficiency of active movement after brain injury.

[Comparative study of external fixator combined with Kirschner wire fixation and Kirschner wires fixation in treatment of cubitus varus deformity in children].

Objective: To analyze the effectiveness comparison of external fixator combined with Kirschner wire fixation and Kirschner wire fixation in the treatment of cubitus varus deformity in children. Methods: A retrospective case-control study was conducted to collect 36 children of postoperative supracondylar humerus fracture complicating cubitus varus deformity between January 2018 and July 2022. Among them, 17 cases were treated with distal humeral wedge osteotomy external fixation combined with Kirschner wire fixation (observation group), and 19 cases were treated with distal humeral wedge osteotomy and Kirschner wire fixation (control group). The baseline data including age, gender, deformity side, time from fracture to operation, carrying angle of the healthy side and preoperative carrying angle of the affected side, elbow flexion and extension range of motion, and lateral condylar prominence index (LCPI) showed no significant difference between the two groups ( P>0.05). The operation time, hospitalization cost, healing time of osteotomy, postoperative complications, and the carrying angle, LCPI, and elbow flexion and extention range of motion were recorded and compared between the two groups. The elbow function was assessed by Oppenheim score at 3 months after operation and at last follow-up. Results: The children in both groups were followed up 13-48 months, with an average of 26.7 months. There was 1 case of needle tract infection in the observation group and 2 cases in the control group, and no nerve injury occurred, the difference in the incidence of complication (5.88% vs 10.53%) between the two groups was not significant ( χ 2=0.502, P=0.593). There was no significant difference in the operation time and fracture healing time between the two groups ( P>0.05); the hospitalization cost of the observation group was significantly higher than that of the control group ( P<0.05). The Oppenheim score of the observation group was significantly better than that of the control group at 3 months after operation ( P<0.05), but there was no significant difference in the Oppenheim score between the two groups at last follow-up ( P>0.05). At last follow-up, the carrying angle of affected side significantly improved in both groups when compared with preoperative ones ( P<0.05); the differences of the pre- and post-operative carrying angle of affected side and elbow flexion and extension range of motion showed no significant differences between the two groups ( P>0.05), but the difference in pre- and post-operative LCPI of the observation group was significantly better than that of the control group ( P<0.05). Conclusion: External fixator combined with Kirschner wire fixation and Kirschner wire fixation both can achieve satisfactory correction of cubitus varus deformity in children, and the former can achieve better short-term functional recovery of elbow joint and reduce the incidence of humeral lateral condyle protrusion.

The Top 100 Classical and Contemporary Papers on Elbow Surgery: A Trend Analysis of Elbow Surgery Literature.

INTRODUCTION: Bibliometric analyses provide an aggregate of the most frequently cited literature in a given field. The purpose of this study was to analyze the top 100 most-cited classical and contemporary papers relating to elbow surgery to serve as a reference for surgeons and trainees for educational and research purposes. METHODS: A search was conducted for all papers containing the term "elbow" in the categories Orthopedics, Surgery, and Sports Science in the Clarivate Web of Science. Classical papers were those published from 1980 to 2009, and contemporary papers were those published from 2010 to 2019. Articles were assessed by country of origin, authors and their credentials, parent journal, level of evidence, and topic. RESULTS: Citation frequency ranged from 86 to 867. Among the classical group, there were more level IV papers compared with level I papers; however, the opposite was true in the contemporary group. The most common topic in the classical group was elbow anatomy and function, and the most common topic in the contemporary group was lateral epicondylitis and medial epicondylitis and associated therapies. DISCUSSION: This bibliometric analysis serves to help guide surgeons and trainees on the highly cited articles and important topics in elbow surgery, demonstrating a shift to prospective randomized controlled trials in recent years. LEVEL OF EVIDENCE: Level V (Systematic Review with Level V as Lowest LOE).

Bone deformity in sports-related elbow osteoarthritis: influence of osteochondritis dissecans of the capitellum-a cross-sectional study.

INTRODUCTION: Sports activity can cause elbow osteoarthritis, which subsequently induces bone deformity. Osteochondritis dissecans (OCD) of the capitellum develops defects of articular surfaces and can exacerbate bone deformity. This study aimed to investigate whether OCD exacerbates deformities in sports-related elbow osteoarthritis. MATERIALS AND METHODS: Twenty-one patients who underwent bilateral computed tomography preoperatively followed by surgery for sports-related elbow osteoarthritis were included. Patients were divided into two groups according to the presence or absence of an OCD history: OCD + (n = 6) and OCD- (n = 15). Bilateral three-dimensional bone models of the humerus, ulna, and radius were created using computed tomography data, and bone deformities were extracted by subtracting healthy mirror models from the affected models using a Boolean operation. Bone deformities were divided into 22 regions in the 3 bones. The volume of the deformity was estimated by correlating the anteroposterior and lateral diameters of the OCD and by comparing the two groups. RESULTS: The anteroposterior diameter of the OCD correlated with the articular surface of the medial trochlear notch, whereas the lateral diameter correlated with the whole ulna, medial gutter of the ulna, whole radius, and lateral side of the radial head. The deformities were 2.2 times larger in the whole humerus, 1.9 times larger in the whole ulna, and 3.0 times larger in the whole radius in the OCD + group than in the OCD- group. The deformities were significantly larger in the OCD + group than in the OCD- group in the radial fossa, posterior capitellum, medial gutter, and lateral gutter in the humerus, medial gutter in the ulna, and lateral, anterior, and posterior sides of the radial head. CONCLUSION: Larger OCD exacerbated deformity in elbow OA, and the presence of OCD exacerbated deformities in sports-related elbow OA. These results demonstrate the highlight of preventing OCD progression.

The use of hinged elbow orthosis following surgical management of terrible triad injuries of the elbow.

PURPOSE: To determine outcomes following surgical management of terrible triad injuries in patients treated with and without a hinged elbow orthosis (HEO) in the post-operative setting. METHODS: This study was a retrospective review of 41 patients who underwent surgical treatment of terrible triad injuries including radial head fracture, coronoid fracture, and ulnohumeral dislocation between 2008 and 2023 with at least 10-week follow-up. RESULTS: Nineteen patients were treated post-operatively without HEO, and 22 patients were treated with HEO. There were no differences in range of motion (ROM) between patients treated with and without HEO in final flexion-extension arc (118.4° no HEO, 114.6° HEO, p = 0.59) or pronation-supination arc (147.8° no HEO, 141.4° HEO, p = 0.27). Five patients treated without HEO and one patient treated with HEO returned to the operating room for stiffness (26%, 5%, p = 0.08). QuickDASH scores were similar between groups (p = 0.69). CONCLUSIONS: This study found no difference in post-operative ROM, complications, or QuickDASH scores in patients treated post-operatively with or without HEO. Based on these results, we cannot determine whether the use of HEO adds additional stability to the elbow while initiating ROM exercises post-operatively.

Reconstruction of the elbow with distal humerus endoprosthetic replacement after tumor resection: a systematic review of the literature and institutional case series.

BACKGROUND: Distal humerus replacement (DHR) is a modular endoprosthesis mainly used for bone reconstruction after resection of primary or metastatic bone lesions. Studies on DHR failure rates and postoperative functional outcomes are scarce. We sought to assess implant survival, modes of failure, and functional outcomes in patients undergoing DHR for oncologic indications. METHODS: A systematic review of the PubMed and Embase databases was performed. PRISMA guidelines were followed for this manuscript. Our study was registered on PROSPERO (457,260). Quality appraisal of included studies was conducted using the STROBE checklist. Prosthetic failure was assessed using the Henderson classification for megaprosthetic failures. We additionally performed a retrospective review of patients treated with a DHR for oncologic indications at a large tertiary care academic center. Weighted means were calculated to pool data. RESULTS: Eleven studies with a total of 162 patients met the inclusion criteria. Mean follow-up was 3.7 years (range, 1.66-8 years). Henderson type 2 failures (aseptic loosening) were the most common mode of failure, occurring in 12% of cases (range, 0%-33%). Five-year implant survival was 72% (range, 49%-93.7%). Mean postoperative Musculoskeletal Tumor Society (MSTS) score was 81.1 (range, 74-84.3). In our institutional case series, 2 out of 5 patients had DHR revision for periprosthetic fracture and aseptic loosening at 16 and 27 months after surgery, respectively. CONCLUSIONS: Distal humerus replacement is a successful reconstruction strategy for tumors of the distal humerus, with high implant survival and good to excellent functional outcomes.

Evaluation of generic EMG-Torque models across two Upper-Limb joints.

Advanced single-use dynamic EMG-torque models require burdensome subject-specific calibration contractions and have historically been assumed to produce lower error than generic models (i.e., models that are identical across subjects and muscles). To investigate this assumption, we studied generic one degree of freedom (DoF) models derived from the ensemble median of subject-specific models, evaluated across subject, DoF and joint. We used elbow (N = 64) and hand-wrist (N = 9) datasets. Subject-specific elbow models performed statistically better [5.79 ± 1.89 %MVT (maximum voluntary torque) error] than generic elbow models (6.21 ± 1.85 %MVT error). However, there were no statistical differences between subject-specific vs. generic models within each hand-wrist DoF. Next, we evaluated generic models across joints. The best hand-wrist generic model had errors of 6.29 ± 1.85 %MVT when applied to the elbow. The elbow generic model had errors of 7.04 ± 2.29 %MVT when applied to the hand-wrist. The generic elbow model was statistically better in both joints, compared to the generic hand-wrist model. Finally, we tested Butterworth filter models (a simpler generic model), finding no statistical differences between optimum Butterworth and subject-specific models. Overall, generic models simplified EMG-torque training without substantive performance degradation and provided the possibility of transfer learning between joints.

Dynamic Stress Ultrasound Assessment of Professional Baseball Players' Elbows After Ulnar Collateral Ligament Reconstruction.

BACKGROUND: There is a paucity of data analyzing dynamic stress ultrasound (SUS) findings in elite pitchers who have undergone ulnar collateral ligament (UCL) reconstruction (UCLR) and returned to sport. PURPOSE: To identify longitudinal, perioperative changes in the elbows of professional baseball pitchers who have undergone UCLR and to compare these findings with a matched cohort of healthy pitchers. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: This study used prospectively collected data from dynamic elbow SUS analyses of professional baseball pitchers within a single Major League Baseball organization. Pitchers were divided into 2 cohorts: a UCLR cohort and healthy cohort. The UCLR cohort eligibility included availability of (1) SUS from preseason of injury/UCLR and (2) SUS from ≥2 years after surgery. These players were 1:1 matched to players with no history of upper extremity injury to form the healthy cohort. Ligament thickness and ulnohumeral joint space at rest and under stress were directly measured. Joint laxity was calculated by subtracting joint space at rest from joint space under stress. The term "relative" was used to describe calculated differences where nondominant measurements were subtracted from dominant-side measurements. RESULTS: Eight pitchers were included in the UCLR group and matched to 8 healthy pitchers (mean age at initial SUS examination, 19.6 years). At a minimum follow-up of 2 years, there were no significant differences between groups in terms of relative or dominant arm rest space, stress space, or laxity. Longitudinally (final measurements - baseline measurements), the mean relative ulnohumeral rest space decreased in the UCLR group and increased in the healthy group (-0.36 mm vs +0.50 mm; P = .032). The finding of increased UCL thickness in the UCLR group was expected, as UCL grafts are typically thicker than native ligaments. CONCLUSION: Ulnhohumeral joint stability was achieved after UCLR as indicated by similar rest space, stress space, and joint laxity in dominant arms compared with a matched healthy cohort. A significant decrease in relative rest space after UCLR may represent the achievement of stability in surgery patients. Alternatively, the increase in ulnohumeral rest space seen in the healthy cohort may represent adaptive changes from pitching at a professional level.

The Utility of Stress Ultrasound in Identifying Risk Factors for Elbow Ulnar Collateral Ligament Tear: A Longitudinal Study of 203 Professional Baseball Players.

BACKGROUND: Injuries to the medial ulnar collateral ligament (UCL) are common among baseball pitchers due to repetitive stress on the soft tissue stabilizers of the elbow during pitching. Dynamic stress ultrasound (SUS) can be used to evaluate the UCL and ulnohumeral joint to identify anatomic risk factors of those who will require UCL reconstruction (UCLR). PURPOSE: To determine whether any adaptive or morphological changes detectable on SUS can predict injury to the UCL in professional baseball pitchers. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 203 professional baseball pitchers who underwent SUS at preseason training sessions over the course of 18 years were categorized into 1 of 2 groups: those without a history of shoulder, arm, elbow, or forearm surgery or injuries (healthy cohort; n = 184) and those who underwent UCLR the same season as SUS (UCLR cohort; n = 19). Ligament thickness, joint spacing, and laxity were compared. An additional matched cohort analysis was conducted using 10 players from each group to detect differences in the progression of UCL and ulnohumeral joint measures in the year before injury. RESULTS: The UCLR cohort, when compared with the healthy cohort, had higher relative (ie, nondominant-side measurements subtracted from dominant-side measurements) resting ulnohumeral joint space (median, 0.50 vs 0.20 mm, respectively; P = .006) and higher rates of hypoechoic foci (57.9% vs 30.4%, respectively; P = .030). Players of both groups had similar dominant UCL thickness (P = .161), ulnohumeral joint space at rest (P = .321), space under stress (P = .498), and laxity (P = .796). Groups did not differ in terms of relative UCL thickness, ulnohumeral joint space under stress, or relative laxity. In the year before UCL injury, the UCLR cohort, compared with the matched healthy cohort, had a greater increase in mean dominant UCL thickness (0.94 vs -0.60 mm, respectively; P = .038) and a greater increase in relative median UCL thickness (1.35 vs -0.35 mm, respectively; P = .045). Players in the healthy cohort were statistically older than those in the UCLR cohort (23 vs 22 years, respectively; P = .004). No differences in ulnohumeral stress spacing or laxity were detected. CONCLUSION: SUS of players who underwent UCLR demonstrated a progressive increase in UCL thickness over 1 year, higher rates of hypoechoic foci, and increased ulnohumeral rest space compared with SUS of uninjured players.

Rotational Motion Due to Skin Shear Deformation at Wrist and Elbow.

The hanger reflex is an illusion phenomenon that induces strong force perception and rotational motion, and it occurs in multiple parts of the body. A potential application of this phenomenon is in upper limb rehabilitation for patients with upper-limb paralysis involving arm rotation. However, the only upper limb movements that have been confirmed in this phenomenon are the inward and outward movements of the wrist, which limits the applicable tasks. Therefore, we attempted to apply the hanger reflex to the elbow and use it simultaneously with the wrist. This phenomenon occurs due to shear deformation of the skin, so shear deformation was presented to the skin on the elbow. When shear deformation of the skin was presented to the elbow in the same manner as in previous studies applied to the wrist, movement and force perception of pronation and supination of the elbow were confirmed. The results of an experiment in which the hanger reflex was simultaneously presented to the elbow and wrist showed that each region independently perceived motion and force.

Treatment and rehabilitation of post-traumatic elbow stiffness with heterotopic ossification.

AIM: To investigate surgical treatment, postoperative rehabilitation and prevention of heterotopic ossification (HO) in patients with post-traumatic elbow stiffness. METHODS: We performed a retrospective review of patients with post-traumatic elbow stiffness combined with HO between 2007 and 2021. This study was performed on a total of 15 patients (18 elbows) admitted to our hospital, consisting of 12 males and 3 females, with post-traumatic stiffness of the elbow combined with HO, where elbow function could not be recovered by rehabilitation and orthosis treatment. Fifteen patients were treated by surgical excision of heterotopic bones and release of elbow contracture combined with postoperative rehabilitation and orthosis-wearing. Comprehensive treatments, including radiation, oral ibuprofen medication, and manipulation techniques to improve range of motion, were used to prevent HO recurrence. The flexion-extension arc and functional score of the elbow were measured after treatment and compared with the preoperative measurements. Roentgenography was used to observe HO recurrence. RESULTS: After surgical treatment and postoperative rehabilitation, the patients' range of motion improved, and the functional score improved considerably. The postoperative flexion-extension arc and The Hospital for Special Surgery (HSS) functional score were statistically significantly higher than the preoperative values (p < 0.01). Roentgenographic examination showed no HO recurrence during the follow-up period. CONCLUSION: Surgical excision of heterotopic bones and elbow contracture release combined with postoperative rehabilitation and preventative HO measures can be an effective treatment for cases of post-traumatic elbow stiffness combined with HO, for which conservative treatment is ineffective.