Forearm Pronation Research Articles

Treating Upper Limb Spasticity With OnabotulinumtoxinA: Subgroup Analysis of US Practice Patterns From the ASPIRE Study (P12-8.012)

<h3>Objective:</h3> To examine onabotulinumtoxinA (onabotA) treatment utilization patterns in the United States (US) for pronated forearm and intrinsic plus hand postures in patients with upper limb (UL) spasticity over a 2-year period. <h3>Background:</h3> In 2021, onabotA received approval in US for injection into 8 additional muscles in the treatment of adult UL spasticity including muscles of the elbow and forearm (brachialis, brachioradialis, pronator teres, and pronator quadratus), as well as intrinsic hand muscles (lumbricals and interossei) and thumb muscles (flexor pollicis brevis and opponens pollicis). More information is required to maximize effectiveness in patients with UL spasticity. <h3>Design/Methods:</h3> This post hoc analysis utilized US data from the multicenter, prospective, observational Adult Spasticity International Registry (ASPIRE) study (NCT01930786) which ran from 2013 through 2017. Participants were adult patients who received onabotA (total dose ≤400 U per treatment session) to UL muscles for spasticity. This analysis was centered on 2021 onabotA expanded label and evaluated treatment utilization for pronated forearm and intrinsic plus hand postures in patients with UL spasticity to determine educational opportunities for optimized treatment in the real-world setting. <h3>Results:</h3> Of 316 US patients in ASPIRE treated for UL spasticity, 135/316 (43%) had pronated forearm and 89/316 (28%) had intrinsic plus hand postures. OnabotA (≤400 U) treatment was delivered to select UL muscles of 45 patients consistent with expanded US label. Baseline characteristics of these 45 patients included a mean age (SD) of 51.3 (16.0) years, 23/45(51%) who were onabotA-naive, and 26/45 (58%) were male. New postures treated included intrinsic plus hand (9/45; 20.0%) and pronated forearm(14/45;31.1%). Of the 36 adverse events (AEs) that occurred, 1 was treatment-related (muscular weakness); no treatment-related serious AEs were reported. <h3>Conclusions:</h3> This analysis provides real-world evidence of the opportunity to educate on the treatment of pronated forearm and intrinsic plus hand postures in accordance with the expanded label for onabotA. <b>Disclosure:</b> Gerard Francisco has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Merz. Gerard Francisco has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Allergan. Gerard Francisco has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Saol. Gerard Francisco has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Shionogi. Gerard Francisco has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Ekso. Gerard Francisco has received personal compensation in the range of $10,000-$49,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Sword Health. Gerard Francisco has received personal compensation in the range of $10,000-$49,999 for serving as an Editor, Associate Editor, or Editorial Advisory Board Member for The Journal of ISPRM. The institution of Gerard Francisco has received research support from Allergan. The institution of Gerard Francisco has received research support from Merz. The institution of Gerard Francisco has received research support from Ipsen. The institution of Gerard Francisco has received research support from Revance. Gerard Francisco has a non-compensated relationship as a Director with American Board of PM&amp;R that is relevant to AAN interests or activities. Gerard Francisco has a non-compensated relationship as a Vice-Presdent with International Society of Physical and Rehabilitation Medicine that is relevant to AAN interests or activities. Dr. Feng has received personal compensation in the range of $5,000-$9,999 for serving on a Scientific Advisory or Data Safety Monitoring board for HuaMed Tech. Dr. Feng has received personal compensation in the range of $5,000-$9,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Precision Neuroscience. Dr. Feng has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Namsa. The institution of Dr. Feng has received research support from NIH. The institution of Dr. Feng has received research support from American heart association . Michael C Munin, 25482 has received personal compensation for serving as an employee of Pacira. Michael C Munin, 25482 has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Merz. Dr. Ngo has nothing to disclose. Marc Schwartz has nothing to disclose. Dr. Sadeghi has received personal compensation for serving as an employee of AbbVie. Dr. Sadeghi has stock in Abbvie/Abbott. Dr. Zuzek has received personal compensation for serving as an employee of AbbVie Inc.. Dr. Zuzek has stock in AbbVie Inc.. Dr. Esquenazi has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Ipsen and Allergan. Dr. Esquenazi has received personal compensation in the range of $5,000-$9,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Ipsen and Allergan. The institution of Dr. Esquenazi has received research support from Ipsen, Allergan and Merz.

ROLE OF RING EXTERNAL FIXATOR IN OPEN INTRA-ARTICULAR DISTAL HUMERUS FRACTURE

Standard fixation for intra-articular distal humerus fracture is open reduction and internal fixation (ORIF). However, high energy fractures of the distal humerus are often accompanied with soft tissue injuries and or vascular injuries which limits the use of internal fixation. In our report, we describe a highly complex distal humerus fracture that showed promising healing via a ring external fixator.A 26-year-old man sustained a Gustillo Anderson Grade IIIB intra-articular distal humerus fracture of the non-dominant limb with bone loss at the lateral column. The injury was managed with aggressive wound debridement and cross elbow stabilization via a hinged ring external fixator. Post operative wound managed with foam dressing. Post-operatively, early controlled mobilization of elbow commenced. Fracture union achieved by 9 weeks and frame removed once fracture united. No surgical site infection or non-union observed throughout follow up. At 2 years follow up, flexion - extension of elbow is 20°- 100°, forearm supination 65°, forearm pronation 60° with no significant valgus or varus deformity.The extent of normal anatomic restoration in elbow fracture fixation determines the quality of elbow function with most common complication being elbow stiffness. Ring fixator is a non-invasive external device which provides firm stabilization of fracture while allowing for adequate soft tissue management. It provides continuous axial micro-movements in the frame which promotes callus formation while avoiding translation or angulation between the fragments. In appropriate frame design, they allow for early rehabilitation of joint where normal range of motion can be allowed in controlled manner immediately post-fixation.Functional outcome of elbow fracture from ring external fixation is comparable to ORIF due to better rehabilitation and lower complications. Ring external fixator in our patient achieved acceptable functional outcome and fracture alignment meanwhile the fracture was not complicated with common complications seen in ORIF.In conclusion, ring external fixator is as effective as ORIF in treating complex distal humeral fractures and should be considered for definitive fixation in such fractures.

Redefining radiocarpal fracture-dislocations with injury specific management and a clinical classification system: a retrospective review.

Unlike articular shear fractures of the distal radius, radiocarpal fracture-dislocations defined as complete dislocation of the lunate from its articular facet of the radius are relatively uncommon. The management principles of these fractures have not been defined and there is no consensus on approach to management of these injuries. The aim of this study is to review our series of radiocarpal fracture-dislocations and propose a radiographic classification to guide surgical management. This study is reported based on STROBE guidelines. A total of 12 patients underwent open reduction and internal fixation. All the fracture-dislocations were dorsal and satisfactory objective outcomes achieved were comparable to literature. Injury morphology-specific management approach was used based on the size of dorsal lip fragment and the volar teardrop fragment attached to the short radiolunate ligament assessed by preoperative CT scans. All patients with known outcome (n = 10) went on to resume their prior occupation and hobbies that included high-demand activities and manual labour at mean follow-up of 27 weeks. Average wrist flexion was 43° and wrist extension was 41° while radial and ulnar deviation were 14° and 18° respectively. Average forearm pronation was 76° and supination was 64° at final follow-up. We describe four injury patterns of radiocarpal fracture-dislocations based on preoperative CT scans that guide fixation. We believe that early recognition of radiocarpal fracture-dislocations and appropriate management can yield satisfactory outcomes.

The AIUM Practice Parameter for the Performance of the Musculoskeletal Ultrasound Examination.

The AIUM Practice Parameter for the Performance of the Musculoskeletal Ultrasound Examination.

Forearm Pronation at Foot Contact: A Biomechanical Motion-Capture Analysis in High School and Professional Pitchers.

It has previously been speculated that baseball pitchers who display excessive forearm pronation at foot contact (FC) have a higher propensity toward ulnar collateral ligament injury and subsequent surgery. To evaluate the association between degree of forearm pronation/supination at FC and throwing arm kinetics in high school and professional pitchers, at both the individual (intrapitcher) and the group (interpitcher) level. Descriptive laboratory study. High school (n = 41) and professional (n = 196) pitchers threw 8 to 12 fastballs while being assessed with a 3-dimensional motion-capture system (480 Hz). Pitchers at each playing level were divided into a supination or pronation subgroup depending on degree of forearm pronation at FC. Regression models were built to observe the relationship between forearm pronation at FC and kinetic and kinematic parameters of interest. At both the individual and the group level of high school and professional pitchers, there was no significant correlation between forearm pronation at FC and elbow varus torque (P min = .21). For every 10° increase in forearm pronation at FC in the individual high school pitcher, elbow flexion at FC decreased by 5°, whereas maximum elbow extension velocity was achieved 0.6% later in the pitch. In addition, elbow medial force increased by 4.1 N and elbow varus torque increased by 0.8 N·m for every 10° increase in forearm supination at FC. For every 10° increase in forearm supination in the individual professional pitcher, ball velocity increased by 0.5 m/s, shoulder external rotation at FC decreased by 11°, and elbow medial force decreased by 5.5 N. Supination- or pronation-predominant forearm motion during the pitch did not significantly differ between playing levels. Excessive forearm pronation at FC was not a significant risk factor for increased throwing arm kinetics for high school or professional pitchers. There was a weak positive association between forearm supination at FC and elbow varus torque in the individual high school pitcher. Ultimately, coaches and pitchers may be better served by redirecting their focus to other mechanical aspects of the pitch that may have stronger associations with injury risk implications as well as performance.

RehaBEElitation: the architecture and organization of a serious game to evaluate motor signs in Parkinson's disease.

The use of serious games (SG) has received increasing attention in health care, and can be applied for both rehabilitation and evaluation of motor signs of several diseases, such as Parkinson's disease (PD). However, the use of these instruments in clinical practice is poorly observed, since there is a scarcity of games that, during their development process, simultaneously address issues of usability and architectural design, contributing to the non-satisfaction of the actual needs of professionals and patients. Thus, this study aimed to present the architecture and usability evaluation at the design stage of a serious game, so-called RehaBEElitation, and assess the accessibility of the game. The game was created by a multidisciplinary team with experience in game development and PD, taking into consideration design guidelines for the development of SG. The user must control the movements of a bee in a 3D environment. The game tasks were designed to mimic the following movements found in the gold-standard method tool-Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS)-for the assessment of individuals with PD: hand opening and closing, hand extension and flexion, hand adduction and abduction, finger tapping, and forearm supination and pronation. The user interacts with the game using a wearable interface device that embeds inertial and tactile sensors. The architecture of RehaBEElitation was detailed using the business process model (BPM) notation and the usability of the architecture was evaluated using the Nielsen-Shneiderman heuristics. Game accessibility was evaluated by comparing the overall scores of each phase between 15 healthy participants and 15 PD patients. The PD group interacted with the game in both the ON and OFF states. The system was modularized in order to implement parallel, simultaneous and independent programming at different levels, requiring less computational effort and enabling fluidity between the game and the control of the interface elements in real time. The developed architecture allows the inclusion of new elements for patient status monitoring, extending the functionality of the tool without changing its fundamental characteristics. The heuristic evaluation contemplated all the 14 heuristics proposed by Shneiderman, which enabled the implementation of improvements in the game. The evaluation of accessibility revealed no statistically significant differences (p<0.05) between groups, except for the healthy group and the PD group in the OFF state of medication during Phase 3 of the game. The proposed architecture was presented in order to facilitate the reproduction of the system and extend its application to other scenarios. In the same way, the heuristic evaluation performed can serve as a contribution to the advancement of the SG design for PD. The accessibility evaluation revealed that the game is accessible to individuals with PD.

Upper Body Pose Estimation Using a Visual–Inertial Sensor System With Automatic Sensor-to-Segment Calibration

Upper body kinematics is essential for motor function assessment and robot-assisted rehabilitation training. Wearable sensor systems, such as inertial measurement units (IMUs), provide affordable solutions to replace laboratory-based motion capture systems for use in daily life. However, the sensor-to-segment calibration often relies on predefined posture or movements, which is hard to perform accurately, particularly for patients with a limited range of motion. A visual–inertial sensor system is presented, which includes three sensor modules attached to the trunk, upper arm, and forearm. Each module has an IMU and an ArUco marker, which can be captured by a camera and the driftless orientation of the modules is computed from visual–inertial fusion. The sensor-to-segment transformations are calibrated from a period of arbitrary arm movements in either a 2-D plane or 3-D space, simulating the training process assisted by end-effector robots. Experiments were conducted to validate the feasibility and evaluate the accuracy of the proposed method. The estimated shoulder and elbow joint angles correlated well ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$&gt;$ </tex-math></inline-formula> 0.986) with the ground truth from the optical motion capture (OMC) system. The joint angles presented low root-mean-square errors (RMSEs) ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$&lt; 4^{\circ }$ </tex-math></inline-formula> ) except for the forearm pronation–supination angle (9.34°), which relied on manual alignment. The sensor system provides a simple and easy-to-use solution for movement assessment during robot-assisted training.

Determining the optimal radiologic wrist and forearm position to visualize screw protrusion in scaphoid fixation.

Surgical fixation of scaphoid fractures may result in unrecognized screw protrusion and subsequent cartilage damage to the adjacent joints. The purpose of this study was to use a three-dimensional (3D) scaphoid model to determine the wrist and forearm positioning that will allow intra-operative fluoroscopic visualization of screw protrusions. Two 3D scaphoid models, with the wrist in neutral and 20° ulnar deviated, were reconstructed from a cadaveric wrist using the Mimics software. The scaphoid models were divided into three segments and further divided into four quadrants in each of the three segments along the scaphoid axes. Two virtual screws, with a 2 and 1 mm groove from the distal border, were placed so that the screws protrude from each quadrant. The wrist models were rotated along the long axis of the forearm and the angles at which the screw protrusions were visualized were recorded. One-millimetre screw protrusions were visualized at a narrower range of forearm rotation angles compared to 2 mm screw protrusions. One-millimetre screw protrusions in the middle dorsal ulnar quadrant could not be detected. Visualization of the screw protrusion in each quadrant varied with forearm and wrist positioning. In this model, all screw protrusions, except 1 mm protrusions in the middle dorsal ulnar quadrant, were visualized with the forearm in pronation, supination or in the mid-pronation position and with the wrist in neutral or 20° ulnar deviated.

Flexor-Pronator Mass Training Exercises Selectively Activate Forearm Musculature.

The flexor-pronator mass of the forearm contributes dynamic stability to the medial elbow. Training this muscle group is essential for overhead athletes, however, there is lack of evidence supporting use of training exercises. The purpose of this study was to measure the extent of EMG activity of the flexor pronator musculature during two distinct forearm strengthening exercises using resistance bands. It was hypothesized that two exercises would elicit at least moderate level of muscle activity, but the activation would be different in the pronator versus the flexor muscles. 10 healthy subjects (all males, age 36±12 years) were included. Surface EMG activity was measured on three muscles of the dominant-side forearm: flexor carpi ulnaris (FCP), flexor digitorum superficialis (FDS), and pronator teres (PT). After measurement of maximal voluntary contraction (MVC) for each muscle, subjects performed wrist ulnar deviation and forearm pronation exercises using elastic band resistance. Resistance was set to elicit moderate exertion (5/10 on the Borg CR10 scale). Order of exercise was randomized and three repetitions of each exercise were performed. Mean peak EMG activity in each muscle across repetitions during the eccentric phase of each exercise was calculated and expressed as a percentage of MVC. Moderate level of activity was defined as 21% of MVC or higher. Peak normalized EMG activity in each muscle was compared using two-way (exercise x muscle) repeated-measures ANOVA with post-hoc pairwise comparisons if a significant interaction was found. There was an exercise by muscle interaction effect (p<0.001). The ulnar deviation exercise selectively activated FCU (40.3%) versus FDS (19.5%, p=0.009) and PT (21.5%, p=0.022). Conversely, the pronation exercise selectively activated FDS (63.8%, p=0.002) and PT (73.0%, p=0.001) versus FDS (27.4%). The ulnar deviation and pronation exercises using elastic band resistance studied targeted and activated the flexor-pronator mass musculature. The ulnar deviation and pronation exercises using elastic band resistance are practical and effective means of training the flexor-pronator mass. These exercises can be readily prescribed to athletes and patients as part of their arm care program.

Closed Reduction Technique for Severely Displaced Radial Neck Fractures in Children.

The described technique is useful for achieving closed reduction of severely displaced (i.e., Judet Type-III and IV) pediatric radial neck fractures. It is widely agreed that radial neck fractures with angulation of >30° should be reduced. Various maneuvers have been described, but none uniformly achieves complete reduction in severely displaced radial neck fractures (Types III and IV)1-4. The aim of the present technique is to achieve closed reduction in these severely displaced radial neck fractures without surgical instrumentation. A stepwise approach is described. First, the radial head is viewed in profile under an image intensifier so that it appears rectangular. Varus stress is applied at the medial aspect of the elbow by the assistant, and thumb pressure is applied at the radial head along the posterolateral aspect of the elbow. This results in partial reduction of the radial head. The elbow is then simultaneously flexed and pronated with continuous pressure over the radial head. This final step anatomically reduces the radial head, and hyperpronating the forearm locks it in the corrected position. Operative alternatives to this technique include intra-focal pin-assisted reduction to achieve closed reduction, the Métaizeau technique of achieving indirect closed reduction of the fracture with the aid of a TENS (Titanium Elastic Nailing System) nail, and open reduction5. Nonoperative techniques have also been described for use with Judet Type-II and III fractures, but not with the severely displaced types described in the present article. This technique takes into consideration the anatomy of the capsule and lateral collateral ligament complex. The biomechanical ligamentotaxis helps in achieving anatomic reduction of the radial head. Placing the forearm in pronation tightens the annular and lateral collateral ligaments and prevents redisplacement. There are potential complications with operative treatment, including the risk of nerve injury with percutaneous reduction techniques and the risks of osteonecrosis, premature epiphyseal fusion, and heterotopic ossification with open reduction. These complications can be avoided by the use of the presently described technique. This technique provided satisfactory clinical outcomes in our previous study6, with none of the 10 patients showing signs of growth disturbance, loss of reduction, or reported complications at 12 months. Terminal restriction of supination was observed in 1 patient. No patient had osteonecrosis or elbow deformity. No patient required conversion to an implant-assisted or open reduction procedure. The steps need to be followed sequentially as described in order to achieve an anatomical reduction.After achieving the reduction, it is necessary to keep the forearm in pronation to maintain the reduction with the aid of the lateral ligament complex.This technique may not work in complex fractures with elbow dislocation because of the lack of ligamentous integrity.In the final step, the elbow is pronated and flexed simultaneously, with sustained pressure over the radial head in order to obtain further correction. This is the most critical step of the technique because anatomic reduction of the partially reduced fracture is achieved at this time. Percut. = percutaneousAP = anteroposteriorCR = closed reductionORIF = open reduction and internal fixation.

Impact of forearm pronation on ultrasound-measured forearm muscle thickness in children and adolescents

AbstractBackground and AimIt was unknown whether ultrasound-measured forearm muscle thickness was impacted by pronation of the forearm. The aim of this study was to investigate the influence of forearm pronation on two forearm muscle thicknesses (MT-ulna and MT-radius).Participants and MethodsFourteen healthy children and adolescents sat on a chair with their right arm comfortably on a table, and their hands were fixed to the board with elastic bands. The probe was placed perpendicularly over the forearm, and the angle of the board was then pronated in 5° increments from −10° to 30°. The average value of the two measures at each angle was used.ResultsThere was evidence that MT-ulna differed across measurement sites (F = 51.086, P &lt; 0.001). For example, the values of the MT-ulna were 2.58 (SD 0.40) cm in standard position (0°), 2.56 (SD 0.41) in −10°, 2.62 (SD 0.41) in 10°, 2.65 (SD 0.42) in 20°, and 2.71 (SD 0.43) in 30°. Follow-up tests found that all sites differed from each other except for −10° and −5° (P = 0.155) and 10° and 15° (P = 0.075). There was also evidence that the MT-radius differed across measurement sites (F = 22.07, P &lt; 0.001). Follow-up tests found that many but not all sites differed from each other.ConclusionOur results suggest that MT-ulna increases and MT-radius decreases due to forearm pronation from the standard position (0°). When determining the forearm position using the 95% limits of agreement, we recommend the forearm position within ±5° of the standard forearm position when measuring forearm MT.

Incidence and pattern of concurrent capitellum fracture associated with radial head and neck fractures

BackgroundRadial head and neck fracture is a common fracture around the elbow. It is mostly caused by axial or valgus loading after a fall in elbow extension and forearm pronation. When a radial head and neck fracture occurs, the capitellum collides with the radial head and experiences a shear force, leading to capitellum fracture. The primary aim of this study was to evaluate the incidence of concurrent capitellum fracture and analyze its patterns among patients treated for radial head and neck fractures based on computed tomography. Secondary aim is to determine factors associated with concurrent capitellum fractures. HypothesisCapitellum fractures are more common than expected in radial head and neck fractures and show a consistent pattern. With the higher the Mason type fracture, the higher the incidence of concurrent capitellum fracture will be shown. MethodsA total of 101 patients treated surgically (27 patients) or non-surgically (74 patients) for radial head and neck fractures from January 2017 to December 2020 were retrospectively analyzed. Initial computed tomography was reviewed to identify concurrent capitellum fractures. A fracture was diagnosed when the bone continuity was lost in two consecutive images in any one of the three directions of computed tomography scan images. Seventeen patients with capitellum fractures were classified as group 1 and 84 patients without capitellum fractures as group 2. Each group of patients was assessed using Mason classification, whether fracture extended to the radial neck or not, fracture location, and treatment method. To determine the fracture location, radial head was trisected using three anatomical landmarks: safe zone, posteromedial zone, and anteromedial zone. And it was determined as the location where the fracture was most comminuted. ResultsThe average age of the 101 patients was 44.6 years old. There were 54 (53.5%) males and 47 (46.5%) females. Capitellum fracture was accompanied in 17 cases. Its incidence was 16.8%. The rate of accompanying capitellum fracture was 9.5% (6/63) for Mason type 1, 25.0% (6/24) for Mason type 2, and 41.7% (5/12) for Mason type 3. The ratio of radial neck extension of fracture was significantly higher in group 2. There was no isolated radial neck fracture in group 1. However, there were 33 in group 2. After eliminating isolated radial neck fracture patients, significantly more fractures were located in the safety zone in group 1. Group 1 had a significantly higher rate of surgical treatment than group 2 (52.9% (9/17) vs. 21.4% (18/84) p=0.007). ConclusionFor radial head and neck fractures, the higher the Mason type fracture, the higher the incidence of concurrent capitellum fracture. When the fracture extended to the radial neck, the comorbidity of the capitellum fracture was decreased. Among radial head fractures, when the fracture was located in the safe zone, the comorbidity of capitellum fracture was increased. The rate of surgical treatment was higher in radial head and neck fracture patients with concurrent capitellum fractures. Level of evidenceIV; diagnostic study.

Cadaveric and Ultrasound Validation of Percutaneous Electrolysis Approach at the Distal Biceps Tendon: A Potential Treatment for Biceps Tendinopathy.

Distal biceps brachii tendinopathy is a musculoskeletal pain condition-comprising chronic intrasubstance degeneration with alterations of the tendon structure-that is difficult to treat. Preliminary evidence suggests a positive effect for pain and related disability of percutaneous electrolysis treatment in patients with tendinopathy. Ultrasound is an excellent diagnostic tool to identify tendon injuries, such as tendinopathy, and to guide treatment approaches. Different approaches using ultrasound evaluation of the biceps tendon have been described. Our aim was to determine the validity and safety of a percutaneous electrolysis approach, targeting insertion of the distal tendon of biceps brachii, in both human (ultrasound-guided) and Thiel-embalmed cadaver (not ultrasound-guided) models. There were two approaches evaluated: an anterior approach with the elbow in extension and the forearm in supination and a posterior approach with the elbow in flexion and the forearm in pronation. A needle was inserted following the tendon up to its insertion into the radial tuberosity. The anterior approach, both in cadaveric study and US-guided intervention, revealed a close relationship between the distal biceps tendon and the brachial artery. The mean distance of the depth of the biceps tendon distal to the brachial artery was 0.21 ± 0.021 cm in the cadavers and 0.51 ± 0.024 cm in subjects. It was also found that the anterior approach has a potential technical difficulty due to the anatomical location of the brachial artery. With the posterior approach, it was possible to safely identify the tendon insertion and the needle approach, since no important vascular and nervous structures were visualized in the window of insertion of the needle. The clinician rated the posterior approach as low difficulty in all subjects. Current results would support a posterior approach with US guidance as a safe approach for applying the percutaneous electrolysis technique for insertional tendinopathies of the distal biceps brachii tendon. The current study did not assess the effectiveness of the proposed intervention; accordingly, future studies investigating the clinical effectiveness of the proposed intervention are needed.

Use of free radial forearm and pronator quadratus muscle flap: Anatomical study and clinical application.

The authors present an anatomical study and clinical experience with radial forearm flap (RFF) and pronator quadratus muscle (PQM) application in the reconstruction of various body areas. The aim was to describe the anatomical placement and proportions of the PQM, the anatomical location of the major arterial branch of the radial artery supplying the PQM, and the application of this knowledge in clinical practice. The anatomical study was based upon an analysis of 13 fresh adult cadaver upper extremities, of which nine were female and four male; both arms from the same donors were used in four cases. The study of the PQM was performed using a dye-containing intraarterial injection, standard macro- and micro-preparation techniques, and chemical digestion. The data on the PQM size in males and females, thickness of the radial artery branch (the principal artery nourishing the muscle), and its position were analysed. The radial artery branch nourishing the PQM was identified in all cadaveric specimens of the anatomical study. In addition, 12 patients underwent reconstructions of soft and bony tissue defects using a RFF+PQM (pedicled or free flap). The radial artery branch perfusing the PQM was identified in all cases. The flap was used for the management of defects of the head (seven cases), arm (three cases) and lower leg (two cases). The harvest site healed well in all cases and, with the exception of one case in which a partial necrosis of the flap was observed, all flaps remained viable, which demonstrated the safety of the method.

Surgery of Medial Epicondylitis (Golfer's Elbow), an Overview

Golfer's elbow, also known as medial epicondylitis, is a common disease. When doing activities that include wrist flexion and forearm pronation, repetitive forced wrist extension and forearm supination can lead to flexor-pronator tendon degeneration. An ongoing pathologic process in the tendon can lead to structural failure, irreversible fibrosis, or calcification. The most common complaint from patients is chronic, medial-sided elbow pain that gets worse with everyday activity. During the late cocking or early acceleration stages of the throwing action, athletes may have symptoms that are particularly severe. Injections of corticosteroids, activity modification, and NSAIDs are all examples of nonsurgical supportive therapy. After the acute symptoms have subsided, attention is directed toward injury prevention and flexor-pronator mass rehabilitation. Patients with severe symptoms are often the only ones who receive open surgical procedures. Hence the study aimed to summarize and explain the evidences regarding surgical management of medial epicondylitis (golfer’s elbow).

Distal Biceps Tendon Ruptures: Diagnostic Strategy Through Physical Examination

Background: Distinguishing a complete from a partial distal biceps tendon rupture is essential, as a complete rupture may require repair on short notice to restore function, whereas partial ruptures can be treated nonsurgically in most cases. Reliability of physical examination is crucial to determine the right workup and treatment in patients with a distal biceps tendon rupture. Purposes: The primary aim of this study was to find a (combination of) test(s) that serves best to diagnose a complete rupture with certainty in the acute phase (≤1 month) without missing any complete ruptures. The secondary aims were to determine the best (combination of) test(s) to identify a chronic (>1 month) rupture of the distal biceps tendon and indicate additional imaging in case partial ruptures or tendinitis are suspected. Study Design: Cohort study (Diagnosis); Level of evidence, 2. Methods: A total of 86 patients with anterior elbow complaints or suspected distal biceps injury underwent standardized physical examination, including the Hook test, passive forearm pronation test, biceps crease interval (BCI), and biceps crease ratio. Diagnosis was confirmed intraoperatively (68 cases), by magnetic resonance imaging (13 cases), or by ultrasound (5 cases). Results: A combination of the Hook test and BCI (ie, both tests are positive) was most accurate for both acute and chronic ruptures but with a different purpose. For acute complete ruptures, sensitivity was 94% and specificity was 100%. In chronic cases, specificity was also 100%. Weakness on active supination and palpation of the tendon footprint provided excellent sensitivity of 100% for chronic complete ruptures and partial ruptures, respectively. Conclusion: The combination of a positive Hook test and BCI serves best to accurately diagnose acute complete ruptures of the distal biceps tendon. Weakness on active supination and pain on palpation of the tendon footprint provide excellent sensitivity for chronic complete ruptures and partial ruptures. Using these tests in all suspected distal biceps ruptures allows a physician to refrain from imaging for a diagnostic purpose in certain cases, to limit treatment delay and thereby provide better treatment outcome, and to avoid hospital and social costs.

The role of sensory feedback from carpal sinus hairs in locomotor kinematics of rats (Rattus norvegicus, Rodentia) during walking on narrow substrates

Carpal sinus hairs on the forearms are assumed to have evolved within the stem lineage of Theria. The presence and similar position of these specialized tactile hairs in scansorial and terrestrial species as well as earlier studies on rats indicate a biological role in sensing substrate irregularities in high structured environments to ensure the dynamic stability of the body during locomotion. While these sensors were considered as one functional unit until so far, the present study deals with the biological role of the single tactile hairs of the trident, assuming a role in sensing substrate diameters and adapting limb coordination and body posture to different arboreal inclinations. To investigate the influence of each hair, we studied the locomotion of rats on poles of two different diameters whereby we selectively removed individual carpal sinus hairs. The rats walked at speeds ranging from 0.12 m/s to 0.58 m/s. Normal-light high-speed cameras and x-ray fluoroscopy visualized the hairs and body dynamics during locomotion. The time lag between first contact of the hairs to the branch until contact of the forepaw was 56–108 ms. Within this time window the pronation/supination of the paw and anterior body posture are adjusted to the substrate diameter. We presume that the most proximal sinus hair (located between the medial and lateral one) senses the paw-substrate distance through the increasing bend from its first branch-contact until the contact of the paw. The medial and the lateral hairs touch the pole sides and thereby, may collect information about the properties of the small-diameter substrate. The removal of single hairs from the group results in minor changes of kinematic parameters, but locomotor stability is seriously impaired when more than one hair is cut. The kinematic responses span from a more crouched body posture and higher forearm pronation to paw slipping, muscle tremor or complete refusal to walk on the narrow substrate.

No association between dynamic trunk flexion strength and throwing velocity in elite women handball players

BACKGROUND: The relationship between strength and throwing velocity is much investigated in handball, but core strength is largely ignored. Only four studies have investigated the effect of core training on handball throwing velocity, reporting conflicting results in amateur players. However, lack of specificity and deficient technical execution of throwing in amateurs can obscure the results. OBJECTIVE: To examine the direct association between trunk flexion strength and throwing velocity in elite handball players, using women as a model. METHODS: Sixteen women players from an elite-level Norwegian handball team participated in the study. Strength in trunk flexion, shoulder extension, internal shoulder rotation, and forearm pronation was assessed using isokinetic dynamometer measurements (peak moment, total work, angular impulse). Throwing velocity in both the standing throw with run-up and the jump throw was determined from motion capture measurements. To account for arm strength, the association between trunk flexion strength and throwing velocity was examined using partial correlation analyses. RESULTS: No significant association was found between any measure of trunk flexion strength and throwing velocity for either throwing technique (explained variance ⩽ 13.7%). CONCLUSIONS: The results indicate that isolated, dynamic trunk flexion strength is not a differentiating factor for handball throwing velocity in elite women players.

Comparison of the clinical and radiographic outcomes of plate fixation versus new-generation locked intramedullary nail in the management of adult forearm diaphyseal fractures.

This study aimed to compare functional and radiographical outcomes following intramedullary nailing (IMN) versus plate and screw osteosynthesis in managing patients with diaphyseal forearm fractures. Forty-six patients (27 male, 19 female) were included in this retrospective study. Of these, 25 were treated with plate osteosynthesis and 21 with IMN. The mean age was 32.4 (range, 19-67) years in the plate group and 28.8 (range, 18-64) years in the IMN group. The mean follow-up was 22.3 (range, 12-36) months in the IMN group and 24.8 (range, 12-48) months in the plate group. Functional outcomes were evaluated based on the forearm pronation/supination range of motion, grip strength, Disabilities of the Arm, Shoulder, and Hand (DASH) score, and Grace-Eversmann scoring criteria. The median time to union was 13.6 weeks in the plate group and 10.9 weeks in the IMN group (p<0.05). Union was achieved in 24 of 25 patients in the plate group (96%) and all patients in the IMN group (100%). The mean operative time was 69.7 (range, 45-110) minutes in the IMN group and 88.2 (range, 50-130) minutes in the plate group. The mean fluoroscopy time was 2.7 seconds in the plate group and 21.3 seconds in the IMN group. The mean length of hospital stay was five (range, 3-9) days in the plate group and four (range, 3-10) days in the IMN group. The mean operative time was significantly shorter in the IMN group (p < 0.05), while the mean fluoroscopy time was longer in the IMN group (p < 0.05). There was no significant difference between the groups in forearm pronation and supination, grip strength, DASH score, and Grace-Eversmann scoring criteria. Locked IMNs seem a viable alternative to ORIF with plate osteosynthesis for adult diaphyseal forearm fractures with similar healing rates, functional scores, and shorter operative times. Level III, Therapeutic Study.

MECOM-associated syndrome: a literature review and case reports

Mutations in the MECOM gene (MDS1 and EVI1 complex locus) may be one of the causes of a rare combination of congenital radioulnar synostosis resulting in extremely limited forearm pronation and supination, and amegakaryocytic thrombocytopenia. The clinical spectrum of the disease can range from isolated radioulnar synostosis with or without hematologic manifestations to severe bone marrow failure without skeletal abnormalities. Other phenotypic manifestations include clinodactyly, brachydactyly, cardiac and renal malformations, presenile hearing loss, and B-cell deficiency. In view of the heterogeneity of phenotypic manifestations of the disease, the term “MECOM-associated syndrome” was proposed for all patients with mutations in the MECOM gene. Here we report 3 pediatric cases of MECOM-associated syndrome with different clinical manifestations, diagnostic approaches, therapeutic options, and outcomes. The patient’s parents agreed to use the information, including the child’s photo, in scientific research and publications.