Interlocking intramedullary nail for forearm diaphyseal fractures in adults-A systematic review and meta-analysis of outcomes and complications.

PURPOSE: The purpose of this systematic review is to examine the outcomes, complications, and potential advantages of using anatomical interlocking intramedullary nails (IMN) in the treatment of radius and ulnar shaft diaphyseal fractures in adults. METHODS: Medline, Embase, Web of Science, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) databases were searched between January 2000 and January 2023. Studies meeting criteria were observational or randomized controlled trials evaluating outcomes in IMN for adult diaphyseal forearm fractures. Standardized data extraction was performed and a quality assessment tool was used to evaluate individual study methodology. Descriptive statistics for interventions, functional outcomes, and complications were reported. Meta-analysis was performed for patient-reported outcome measures and operative time. RESULTS: A total of 29 studies involving 1268 patients were included with 764 (60%) undergoing IMN, 21% open reduction and internal fixation (ORIF), and 9% hybrid fixation. There was no significant difference between groups in DASH and Grace-Eversmann scores. Operative time was significantly shorter in IMN compared with ORIF. The DASH scores were: 13.1 ± 6.04 for IMN, 10.17 ± 3.98 for ORIF, and 15.5 ± 0.63 in hybrids. Mean operative time was 65.3 ± 28.7 in ORIF and 50.8 ± 17.7 in IMN. Complication rates were 16.7% in the IMN group, 14.9% in ORIF, and 6.3% in hybrid constructs. There were 11 cases of extensor pollicis rupture in the IMN group. Average IMN pronation and supination were 78.3° ± 7.9° and 73° ± 5.0°, respectively. Average ORIF pronation and supination was 82.15° ± 1.9° and 79.7° ± 4.5°, respectively. CONCLUSIONS: Similar functional outcomes and complication rates along with shorter operative times can be achieved with IMN compared with ORIF. The use of IMN is promising, however, higher quality evidence is required to assess appropriate indications, subtle differences in range of motion, implant-related complications, and cost-effectiveness. Trail Registration PROSPERO (International Prospective Register of Systematic Reviews) (ID: CRD42022362353).

Sensor-Based Quantitative Assessment of Children's Fine Motor Competence: An Instrumented Version of the Placing Bricks Test.

The assessment of fine motor competence plays a pivotal role in neuropsychological examinations for the identification of developmental deficits. Several tests have been proposed for the characterization of fine motor competence, with evaluation metrics primarily based on qualitative observation, limiting quantitative assessment to measures such as test durations. The Placing Bricks (PB) test evaluates fine motor competence across the lifespan, relying on the measurement of time to completion. The present study aims at instrumenting the PB test using wearable inertial sensors to complement PB standard assessment with reliable and objective process-oriented measures of performance. Fifty-four primary school children (27 6-year-olds and 27 7-year-olds) performed the PB according to standard protocol with their dominant and non-dominant hands, while wearing two tri-axial inertial sensors, one per wrist. An ad hoc algorithm based on the analysis of forearm angular velocity data was developed to automatically identify task events, and to quantify phases and their variability. The algorithm performance was tested against video recordings in data from five children. Cycle and Placing durations showed a strong agreement between IMU- and Video-derived measurements, with a mean difference <0.1 s, 95% confidence intervals <50% median phase duration, and very high positive correlation (ρ > 0.9). Analyzing the whole population, significant differences were found for age, as follows: six-year-olds exhibited longer cycle durations and higher variability, indicating a stage of development and potential differences in hand dominance; seven-year-olds demonstrated quicker and less variable performance, aligning with the expected maturation and the refined motor control associated with dominant hand training during the first year of school. The proposed sensor-based approach allowed the quantitative assessment of fine motor competence in children, providing a portable and rapid tool for monitoring developmental progress.

Portable Head-Mounted System for Mobile Forearm Tracking.

Computer vision (CV)-based systems using cameras and recognition algorithms offer touchless, cost-effective, precise, and versatile hand tracking. These systems allow unrestricted, fluid, and natural movements without the constraints of wearable devices, gaining popularity in human-system interaction, virtual reality, and medical procedures. However, traditional CV-based systems, relying on stationary cameras, are not compatible with mobile applications and demand substantial computing power. To address these limitations, we propose a portable hand-tracking system utilizing the Leap Motion Controller 2 (LMC) mounted on the head and controlled by a single-board computer (SBC) powered by a compact power bank. The proposed system enhances portability, enabling users to interact freely with their surroundings. We present the system's design and conduct experimental tests to evaluate its robustness under variable lighting conditions, power consumption, CPU usage, temperature, and frame rate. This portable hand-tracking solution, which has minimal weight and runs independently of external power, proves suitable for mobile applications in daily life.

Is Tourniquet Pain the Result of Increased Compartment Pressure in the Forearm?

ABSTRACT: The pneumatic tourniquet has been a mainstay in upper extremity surgery by allowing the surgeon to operate in a blood-free field. Many upper extremity surgical procedures are done under local anesthesia or minimal sedation, and the problem of tourniquet pain is a vexing one. The question is posed: Is tourniquet pain the result of increased compartment pressure in the forearm? This study measured compartment pressures of the volar forearm in 10 healthy normotensive volunteers before inflation of a pneumatic tourniquet and compared it with pressure measurements taken while the tourniquet was still inflated after 15 minutes. Compartment pressures were measured using a Stryker needle manometer; all measurements were taken in the volar forearm by the senior author (C.H.M.). There was no increase in the volar/flexor compartment pressure of the forearm after 15 minutes of tourniquet inflation. All subjects complained of pain of the forearm, characteristically what is commonly called "tourniquet pain." We therefore conclude that in the upper extremity, at least for relatively short operating times, appropriate inflation of a tourniquet does not induce the early onset of increased compartment pressure in the forearm.

Acute blockage of forearm supination due to flap tear of the triangular fibrocartilage disc: A case report.

RATIONALE: Acute blockage of forearm supination has been reported in several studies. It is caused by loose bodies in the wrist joint, extensor carpi ulnaris tendon interposition, and distal radioulnar joint (DRUJ) injuries, including forearm bone fractures. Some studies have reported cases of DRUJ injuries caused by triangular fibrocartilage complex (TFCC) tears.We report a case of acute blockage of forearm supination after minor trauma and suggest a possible TFCC tear when a patient complains of forearm supination blocking. In addition, we present a comparison between our case and other reports on etiology, magnetic resonance imaging (MRI) findings, and arthroscopic findings, and show the specific characteristics of our case. PATIENTS CONCERNS: A 22-year-old male presented with left wrist pain as the chief complaint. He was injured 2 months prior to pushing his left hand on the floor during exercise. Physical examination showed a relative limitation of range of motion (ROM) in the left wrist of about 10° in flexion and about 15° in extension compared with the right side. The patient also complained of supination limitation and volar side wrist pain during supination. The patient showed tenderness in the axial compression test. DIAGNOSES: Plain radiographs showing no abnormalities. MRI showed a TFCC tear in the central portion. A torn flap of the TFCC was interposed on the volar side of the DRUJ. INTERVENTIONS: Arthroscopic surgery of the left wrist joint was performed. Arthroscopic examination revealed a tear in the TFCC on the radial side. A torn flap was interposed on the volar side of the DRUJ. We removed the flap from the DRUJ using an arthroscopic grasper and partially resected it. OUTCOMES: Intraoperative tests showed no locking and the forearm was well supinated. Two months after the surgery, the patient had no pain and showed full forearm supination. LESSONS: DRUJ blocking due to a TFCC tear should be suspected when acute blockage of forearm supination occurs after minor trauma. MRI is helpful for diagnosis; however, we suggest that the diagnosis should be confirmed through arthroscopy. Symptoms can be resolved by surgical treatment using arthroscopy.

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.

[Prefabricated curvature internal fixation with Kirschner needle for forearm fracture in children].

OBJECTIVE: To explore clinical effect of precast curvature internal fixation with Kirschner needle in treating forearm fracture in children. METHODS: From October 2019 to December 2022,32 children with forearm fractures were treated with precast curvature internal fixation with Kirkler's needles,including 25 males and 7 females,aged from 3 to 15 years old with an average of (8.0±0.5) years old,18 patients on the left side and 14 on the right side,24 patients with double fractures of radial and ulna,3 patients with Monteggia fractures,and 4 patients with Galeazzi fractures,and 1 patient with radial neck fracture of crooked cap. Operation time,intraoperative blood loss,C-arm fluoroscopy,fracture healing time and complications were recorded,and disabilities of arm,shoulder and hand (DASH) scale and Grace-Eversman forearm double fracture evaluation system were used to evaluate clinical efficacy of precast curvature internal fixation with Kirschner's needle for forearm fracture in children. RESULTS: All 32 patients were followed up for 2 to 12 months with an average of (7.16±2.51) months. Intraoperative blood loss was (20.68±5.50) ml,C-arm fluoroscopy was(5.80±2.50),and operation time was (24.34±5.10) min,fracture healing time was (8.82±1.62) weeks. Two patients occurred complications,including postoperative rupture of extensor pollicis longus tendon in 1 patient and obvious displacement of fracture caused by rotation of prefabricated curvature Kirschler needle on bone marrow cavity in 1 patient. DASH scores ranged from 0 to 16 scores with an average of (8.32±1.50) scores. According to Grace-Eversman double fracture evaluation system,28 patients got excellent result,2 good and 2 fair. CONCLUSION: The treatment of forearm fracture with Kirschner's needle prefabricated curvature internal fixation has advantages of less trauma,less bleeding,good reduction,stable fixation,fast fracture healing and good functional recovery.

A Novel Operation Technique for Forearm Deformities in Patients with Brachial Plexus Birth Injury: Retrospective Analysis of 14 Patients.

Background: We aimed to evaluate the effectiveness of our novel operation technique that included radial shaft shortening plus supination producing osteotomy and transfer of the biceps brachii tendon to the brachialis tendon in patients with chronic radial head dislocation secondary to brachial plexus birth injury (BPBI). Methods: Fourteen patients with chronic radial head dislocation resulting from BPBI were included in this study, with a minimum 1-year postoperative follow-up period. All patients underwent the same surgical procedure. The range of motion of affected elbow was measured with a standard goniometer. The Mayo Elbow Performance Score (MEPS) was used to measure for evaluation of functional result of these patients. The affected elbow radiograph also obtained in the last visit for evaluation of compatibility of the radiocapitellar joint. Results: Fourteen patients (10 males and 4 females) were included in the study. The average age at the time of surgery was 7.2 (5-8) years and average follow-up was 73.2 ± 19 (36-131) months. Although the forearm active-passive pronation decreased, active-passive supination significantly improved postoperatively (p < 0.001). Ten patients had excellent MEPS results (90 and above), two patients with good results (75 and 80), one patient with fair (65) and one patient with poor result (55). Radiocapitellar reduction was achieved in 78.5% (11/14) of the patients. Conclusions: The novel surgical techniques that included radial shaft shortening plus supination producing osteotomy and transfer of the biceps brachii tendon to the brachialis tendon improved the functional outcomes of patients with chronic radial head dislocation secondary to BPBI. Level of Evidence: Level IV (Therapeutic).

Analyzing the reduction quality of the distal radioulnar joint after closed K-wire transfixation in a cadaver model: is supination or neutral position superior?

INTRODUCTION: Distal radioulnar joint (DRUJ) instabilities are challenging and their optimal treatment is controversial. In special cases or when reconstruction of the stabilizing triangular fibrocartilage complex (TFCC) fails, K-wire transfixation can be performed. However, no consensus has been reached regarding the rotational position of the forearm in which this should be done. Therefore, it was investigated whether anatomical reduction would best be achieved by transfixation in neutral position or supination of the forearm. MATERIALS AND METHODS: Twelve cadaveric upper limbs were examined before dissection of the DRUJ stabilizing ligaments and after closed transfixation in both positions by C-arm cone-beam CT. Whether this was first done in neutral position or in supination was randomized. The change in the radioulnar ratio (RR) in percentage points (%points) was analyzed using Student's t-test. RR was used since it is a common and sensitive method to evaluate DRUJ reduction, expressing the ulnar head's position in the sigmoid notch as a length ratio. RESULTS: The analysis showed an increased change in RR in neutral position with 5.4 ± 9.7%points compared to fixation in supination with 0.2 ± 16.1%points, yet this was not statistically significant (p = 0.404). CONCLUSIONS: Neither position leads to a superior reduction in general. However, the result was slightly closer to the anatomical position in supination. Thus, transfixation of the DRUJ should be performed in the position in which reduction could best be achieved and based on these data, that tends to be in supination. Further studies are necessary to validate these findings and to identify influential factors.

The effectiveness of therapeutic craft-making activities in treating lower-third forearm fracture: study protocol for a randomized controlled trial.

BACKGROUND: Occupational Therapists use craft-making activities as therapeutic interventions to improve physical and psychological functioning of injured people. Despite the therapeutic effects, craft-making is not routinely used in hand rehabilitation as an intervention for patients with upper limb fractures. These patients often experience physical and psychosocial issues; however, without supportive evidence, therapists hesitate to integrate craft-making into upper limb rehabilitation. PURPOSE: This study aims to determine the effect of a conventional therapy combined with therapeutic craft-making on disability, post-traumatic stress, and physical performance in patients with lower-third forearm fractures. METHODS: Priori analysis determined that 38 patients will be needed for this superiority randomized controlled trial to be conducted in a hand and upper limb rehabilitation center. Eligible participants must comprehend English, be diagnosed with lower-third forearm fracture(s) stabilized by open reduction internal fixation, and referred to therapy within 2-4 weeks of surgery. Following the CONSORT guidelines, participants will be randomly assigned to a Control (conventional therapy) group or an Intervention (conventional therapy and craft) group. Twice weekly for 6 weeks, Therapist A will provide both groups with 1-h of conventional therapy while the Intervention group will also receive 15 min of craft-making supervised by the Researcher. The primary outcome of disability will be measured with the Quick-Disabilities of Arm, Shoulder and Hand. The secondary outcome measurements include the Patient-Rated-Wrist-Evaluation; Impact of Event Scale-revised and physical performance, i.e., the Purdue Pegboard Test, AROM, and grip strength. All outcome measures will be obtained by Therapist B prior to the 1st therapy visit and after the 12th visit. Descriptive analysis will be done for the categorical and continuous data and a mixed model ANOVA for analysis of the initial and final assessment scores within and between groups. RESULTS: This study is ongoing. DISCUSSION: The intent of this study is to determine if therapeutic crafts have value as an intervention when used in combination with conventional therapy for patients with lower-third forearm fractures. If the value of crafts is supported, this evidence may reduce hesitancy of therapists to implement craft-making with patients referred to hand therapy after upper limb fracture. CONCLUSION: This study is ongoing. TRIAL REGISTRATION: ANZCTR, ACTRN12622000150741. Retrospectively registered on 28 January 2022 https://anzctr.org.au/Trial/Registration/TrialReview.aspx?id=382676&isReview=true ..

Reproduction of forearm rotation dynamic using intensity-based biplane 2D-3D registration matching method.

This study aimed to reproduce and analyse the in vivo dynamic rotational motion of the forearm and to clarify forearm motion involvement and the anatomical function of the interosseous membrane (IOM). The dynamic forearm rotational motion of the radius and ulna was analysed in vivo using a novel image-matching method based on fluoroscopic and computed tomography images for intensity-based biplane two-dimensional-three-dimensional registration. Twenty upper limbs from 10 healthy volunteers were included in this study. The mean range of forearm rotation was 150 ± 26° for dominant hands and 151 ± 18° for non-dominant hands, with no significant difference observed between the two. The radius was most proximal to the maximum pronation relative to the ulna, moved distally toward 60% of the rotation range from maximum pronation, and again proximally toward supination. The mean axial translation of the radius relative to the ulna during forearm rotation was 1.8 ± 0.8 and 1.8 ± 0.9 mm for dominant and non-dominant hands, respectively. The lengths of the IOM components, excluding the central band (CB), changed rotation. The transverse CB length was maximal at approximately 50% of the rotation range from maximum pronation. Summarily, this study describes a detailed method for evaluating in vivo dynamic forearm motion and provides valuable insights into forearm kinematics and IOM function.

Simulating contamination of the operator and surrounding environment during wound debridement through fluorescent labelling.

We investigated the contamination of the operator and the surrounding environment during wound debridement through simulated operations using fluorescent labelling. On-site simulated operation assessment was performed before and after the training. Oranges and square towels were used to simulate wounds and the inpatient units, respectively. Fluorescent powder was applied to the surfaces. Operations on oranges simulated bedside debridement, and the postoperative distribution of the fluorescent powder was employed to reflect the contamination of the operator and the surrounding environment. During the pre-training assessment, contamination was observed in 28 of the 29 trainees. The commonly contaminated parts were the extensor side of the forearm, middle abdomen, upper abdomen, and hands. The right side of the operating area was contaminated in 24 trainees. During the post-training assessment, contamination was observed in 13 of the 15 trainees. The commonly parts were the hands, extensor side of the forearm, and the lower abdomen. The front, back, left, and right sides of the operating area were contaminated in 12, 9, 11, and 14 trainees, respectively. Contamination of the treatment cart was observed in 5 trainees. Operator and the surrounding environment can be contaminated during wound debridement. Attention should be paid to hand hygiene, wearing and changing of work clothes, and disinfection of the surrounding environment. Moreover, regular training is recommended.

Does Exerting Grasps Involve a Finite Set of Muscle Patterns? A Study of Intra- and Intersubject Variability of Forearm sEMG Signals in Seven Grasp Types.

Surface Electromyography (sEMG) signals are widely used as input to control robotic devices, prosthetic limbs, exoskeletons, among other devices, and provide information about someone's intention to perform a particular movement. However, the redundant action of 32 muscles in the forearm and hand means that the neuromotor system can select different combinations of muscular activities to perform the same grasp, and these combinations could differ among subjects, and even among the trials done by the same subject. In this work, 22 healthy subjects performed seven representative grasp types (the most commonly used). sEMG signals were recorded from seven representative forearm spots identified in a previous work. Intra- and intersubject variability are presented by using four sEMG characteristics: muscle activity, zero crossing, enhanced wavelength and enhanced mean absolute value. The results confirmed the presence of both intra- and intersubject variability, which evidences the existence of distinct, yet limited, muscle patterns while executing the same grasp. This work underscores the importance of utilizing diverse combinations of sEMG features or characteristics of various natures, such as time-domain or frequency-domain, and it is the first work to observe the effect of considering different muscular patterns during grasps execution. This approach is applicable for fine-tuning the control settings of current sEMG devices.

Arm muscle synergies enhance hand posture prediction in combination with forearm muscle synergies.

Objective.We analyze and interpret arm and forearm muscle activity in relation with the kinematics of hand pre-shaping during reaching and grasping from the perspective of human synergistic motor control.Approach.Ten subjects performed six tasks involving reaching, grasping and object manipulation. We recorded electromyographic (EMG) signals from arm and forearm muscles with a mix of bipolar electrodes and high-density grids of electrodes. Motion capture was concurrently recorded to estimate hand kinematics. Muscle synergies were extracted separately for arm and forearm muscles, and postural synergies were extracted from hand joint angles. We assessed whether activation coefficients of postural synergies positively correlate with and can be regressed from activation coefficients of muscle synergies. Each type of synergies was clustered across subjects.Main results.We found consistency of the identified synergies across subjects, and we functionally evaluated synergy clusters computed across subjects to identify synergies representative of all subjects. We found a positive correlation between pairs of activation coefficients of muscle and postural synergies with important functional implications. We demonstrated a significant positive contribution in the combination between arm and forearm muscle synergies in estimating hand postural synergies with respect to estimation based on muscle synergies of only one body segment, either arm or forearm (p< 0.01). We found that dimensionality reduction of multi-muscle EMG root mean square (RMS) signals did not significantly affect hand posture estimation, as demonstrated by comparable results with regression of hand angles from EMG RMS signals.Significance.We demonstrated that hand posture prediction improves by combining activity of arm and forearm muscles and we evaluate, for the first time, correlation and regression between activation coefficients of arm muscle and hand postural synergies. Our findings can be beneficial for myoelectric control of hand prosthesis and upper-limb exoskeletons, and for biomarker evaluation during neurorehabilitation.

Estimation of Injury Limits at Vulnerable Impact Locations Along the Forearm Via THUMS AM50 Finite Element Model at Airbag Loading Rates.

Side and frontal airbag deployment represents the main injury mechanism to the upper extremity during automotive collisions. Previous dynamic injury limit research has been limited to testing the forearm at either the assumed most vulnerable location to fracture, the distal 1/3rd, or the midpoint. Studies have varied the surface to which impacts were applied, with no clear consensus on the site of greatest vulnerability. The unpredictability of airbag impact location, especially with altered hand positioning, limits the effectiveness of existing forearm injury limits determined from impacts at only one location. The current study quantified the effect of impacts at alternative locations on injury risk along the forearm using the THUMS FE model. Airbag-level impacts were simulated along the forearm on all four anatomical surfaces. Results showed the distal 1/3rd is not the most vulnerable location (for any side), indicating forearm fracture is not solely driven by area moment of inertia (as previously assumed). The posterior forearm was the weakest, suggesting that current test standards underestimate the fracture risk of the forearm. Linear regression models showed strong correlation between forearm fracture risk and bone geometry (cross-sectional area and area moment of inertia) as well as soft-tissue depth, potentially providing the ability to predict forearm injury tolerances for any location or forearm size. This study demonstrated the forearm's vulnerability to fracture from airbag deployments, indicating the need for safety systems to better address injury mechanisms for the upper limb to effectively protect drivers.