Ensemble Learning Method for the Continuous Decoding of Hand Joint Angles.

Human-machine interface technology is fundamentally constrained by the dexterity of motion decoding. Simultaneous and proportional control can greatly improve the flexibility and dexterity of smart prostheses. In this research, a new model using ensemble learning to solve the angle decoding problem is proposed. Ultimately, seven models for angle decoding from surface electromyography (sEMG) signals are designed. The kinematics of five angles of the metacarpophalangeal (MCP) joints are estimated using the sEMG recorded during functional tasks. The estimation performance was evaluated through the Pearson correlation coefficient (CC). In this research, the comprehensive model, which combines CatBoost and LightGBM, is the best model for this task, whose average CC value and RMSE are 0.897 and 7.09. The mean of the CC and the mean of the RMSE for all the test scenarios of the subjects' dataset outperform the results of the Gaussian process model, with significant differences. Moreover, the research proposed a whole pipeline that uses ensemble learning to build a high-performance angle decoding system for the hand motion recognition task. Researchers or engineers in this field can quickly find the most suitable ensemble learning model for angle decoding through this process, with fewer parameters and fewer training data requirements than traditional deep learning models. In conclusion, the proposed ensemble learning approach has the potential for simultaneous and proportional control (SPC) of future hand prostheses.

Potential clinical utility of a novel optical tomographic imaging for the quantitative assessment of hand rheumatoid arthritis.

Optical tomographic imaging (OTI) was reported to be a novel technique for the early diagnosis and disease activity assessment of rheumatoid arthritis (RA). This study aimed to evaluate the clinical utility of OTI for the detection of hand synovitis of RA patients. Manu-scan was used to perform imaging targeting the proximal interphalangeal (PIP) and metacarpophalangeal (MCP) joints in 12 RA patients and three controls. The enrolled RA patients also underwent magnetic resonance imaging (MRI) and bone scintigraphy (BS) to provide reference images. Of the 181 joints feasible for OTI analysis, 140 joints (111 in RA patients and 29 in controls, 77.3%) in which the difference of the OTI indices in the two measurements was within 20% were evaluated. The OTI indices in RA joints were significantly lower than those in control joints (p < 0.001). Overall, the OTI indices in RA joints decreased as the synovitis grades on MRI or BS increased. Moreover, OTI was able to discriminate between RA and control joints (AUC = 0.815, 95% CI 0.739-0.891), even if RA joints were normal on physical examination (AUC = 0.714, 95% CI 0.594-0.834). OTI was in good agreement (kappa = 0.60) with MRI for evaluating synovitis in RA patients and showed positive results in 11.4% of clinically asymptomatic joints. OTI in this study showed the potential to be a supplementary imaging modality for the quantification of synovial inflammation in PIP and MCP joints of RA patients. Further large-scale trials are needed to confirm these findings.

Factors associated with hand joint destruction in Chinese patients with rheumatoid arthritis.

BACKGROUND: There have been no previous report of hand joint destruction prevalence in Chinese rheumatoid arthritis (RA) patients. Therefore, the aim of this study was to investigate the prevalence and potential factors of hand joint destruction among RA patients from Nantong China. In addition, we wanted to examine the differences between functional capacity, psychological status, and quality of life in patients with hand joint destruction compared to those without hand joint destruction. METHODS: A cross-sectional study was conducted from the Affiliated Hospital of Nantong University between July 2015 and June 2016. RA patients completed questionnaires for demographic or clinical variables, the 10-cm Visual Analog Scale for pain, the 28-joint Disease Activity Score-erythrocyte sedimentation rate for disease activity, the Health Assessment Questionnaire-disability index for physical function, the Hospital Anxiety and Depression Scale for anxiety and depression, and the Short Form 36 health survey for quality of life. Laboratory examinations were taken to obtain some biochemical indicators (e.g., rheumatoid factor, anti-cyclic citrullinated peptide antibody). X-ray assessment of hand was performed and hand joint destruction was defined as Sharp score > 0. Independent sample t-test, Mann-Whitney U-test, Chi-square test, and multivariate analysis using backward stepwise logistic regression model were used to analyze these data. RESULTS: One hundred and sixty-one RA patients were included in this study. Radiographic findings revealed that almost 47.2% (n = 76) of patients had hand joint destruction. Multivariate analysis found that education ≤ 9 years (p = 0.041), anti-cyclic citrullinated peptide antibody positive (p = 0.021), high disease activity (p = 0.020), and long disease duration (p < 0.001) were important potential risk factors of hand joint destruction. Participants with hand joint destruction tended to have lower physical function and quality of life, and more severe depressive symptoms compared to individuals without hand joint destruction. CONCLUSIONS: 47.2% of people with RA from Nantong China experienced hand joint destruction. Education, anti-cyclic citrullinated peptide antibody, disease activity, and disease duration had great impacts on hand joint destruction. The results suggested that rheumatologists should pay attention to RA patients' hand joint destruction, especially those with low education levels, anti-cyclic citrullinated peptide antibody positive, high disease activity, and long disease duration by patient education or other ways to improve patients' prognosis.

Surface wear of PyroCarbon implant in metacarpophalangeal joint arthroplasty without radiographic abnormality: A case report.

CASE: A 54-year-old male with osteoarthritis of the right long finger metacarpophalangeal joint underwent PyroCarbon joint arthroplasty. Seven years later the patient presented for metacarpophalangeal joint swelling and pain. The workup was benign, without signs of implant complication or osseous abnormality. He underwent washout and two-stage revision, where gross implant wear and debris not demonstrated by radiograph were found. He then returned to the operating room for reimplantation of a PyroCarbon implant. CONCLUSION: This case demonstrates a novel presentation of aseptic PyroCarbon implant failure in the hand without radiographic abnormality that can alter operative management by reducing operating room returns.

Ability of the European League Against Rheumatism-Outcomes Measures in Rheumatology combined scoring system for grading dorsal joint space synovitis to accurately evaluate ultrasound-detected hand synovitis.

Background: The European League Against Rheumatism-Outcomes Measures in Rheumatology (EULAR-OMERACT) recommend only scanning dorsal spaces for scoring ultrasound-detected hand synovitis. This study evaluated the efficiency of the combined scoring system only depending on dorsal joint spaces synovitis in diagnosing and evaluating ultrasound-detected hand synovitis. Methods: The data of 56 patients who underwent hand joint ultrasonography exams in the Ultrasound Department of West China Hospital, Sichuan University were prospectively collected. The participants formed a random series. The images of each patient included gray-scale (GS) and power Doppler (PD) images of bilateral first to fifth metacarpophalangeal joints (MCP) and the thumb and second to fifth proximal interphalangeal joints (IP). The synovial thickness was measured quantitatively in GS images, and the synovial GS scores in the dorsal joint spaces and PD scores in the dorsal and volar joint spaces were calculated according to the combined EULAR-OMERACT scoring system. Results: The detection rate of synovitis in the first to fifth MCP, thumb and second to fifth proximal IP synovitis were 41.4% (232/560) and 33.9% (190/560), respectively. The sensitivity of only inspecting the dorsal joint spaces with GS ultrasound was 79.3% for MCP and 52.6% for the thumb and second to fifth proximal IPs. The PD scores were higher in the dorsal joint spaces than in the volar joint spaces (P value <0.001). The combined scores were higher than either the GS or PD scores alone in the dorsal joint spaces (P value of the combined scores vs. GS scores =0.001; P value of the combined scores vs. PD scores <0.001). Conclusions: Adopting the EULAR-OMERACT combined scoring standard is recommended to evaluate ultrasound-detected hand synovitis, as determined by the highest value of the GS scores or the PD scores. More specifically, PD scores can mainly be used to appraise the dorsal joint spaces. However, GS scores should be used to evaluate both the dorsal joint spaces and the volar joint spaces.

Effect of transcranial direct current stimulation combined with a smart hand joint training device on hand dysfunction in patients with early stroke.

INTRODUCTION: The aim of this study was to investigate the effect of transcranial direct current stimulation (tDCS) combined with a smart hand joint training device on hand dysfunction in patients with early stroke. MATERIAL AND METHODS: This study was a randomized controlled trial, which was conducted in the neurology department in our hospital. From March 2019 to January 2021, 60 patients diagnosed with early stroke hand dysfunction were selected. A random number table method was used to divide patients equally into control group (smart hand joint training device group) and intervention group (tDCS and smart hand joint training device group). Before and after treatment, Brunnstrom six-level staging, Fugl-Meyer motor function score (wrist hand part), hemiplegic finger function examination, and hemiplegic hand function classification evaluation were applied in both groups. Main outcome measures were Brunnstrom motor function staging (hand part), functional evaluation of hemiplegic fingers, and Fugl-Meyer motor function score (wrist hand part). RESULTS: After treatment, compared with control group, the results in intervention group of Brunnstrom six-level staging and hemiplegic hand function classification evaluation showed obvious improvement (p = 0.000), and the result of hemiplegic fingers' functional evaluation also improved (p = 0.026). After treatment, Fugl-Meyer motor function scores were 6.73 ±6.65 (control group) and 9.8 ±6.66 (intervention group). Slight tDCS-related adverse events occurred in one patient (3.33%) in intervention group. None in either group discontinued treatment. CONCLUSIONS: Both the smart hand joint training device alone and tDCS combined with the smart hand joint training device can improve hand function of patients with early stroke to varying degrees, but the treatment effect of tDCS combined with the smart hand joint training device is more significant.

Ultrasound entheseal abnormalities at the distal interphalangeal joints and clinical nail involvement in patients with psoriasis and psoriatic arthritis, supporting the nail-enthesitis theory.

OBJECTIVE: It has been shown that nail involvement in psoriasis is associated with systemic enthesopathy. Our objective was to evaluate the association of nail involvement and enthesopathy at distal interphalangeal joint (DIP) level in psoriasis (PsO) and psoriatic arthritis (PsA) patients. METHODS: Consecutive patients (54 PsO and 56 PsA) seen at the outpatients clinic in this cross-sectional study were included. All patients underwent both clinical and ultrasound (US) assessment on the same day. RESULTS: US revealed enthesopathy in at least 1 DIP joint in 9 patients with PsO (17%, 95% CI: 8-29%) and in 18 patients with PsA (32%, 95% CI: 20-46%). US extensor tendon enthesopathy was detected in a higher proportion of fingers with clinical nail involvement compared with fingers without clinical nail involvement, both in PsO and PsA patients (61.2% vs 16.8%, p < 0.0001 and 60.1% vs 22%, p < 0.0001, respectively). Among patients with PsO, 20% (95% CI: 7-41%) and 14% (95% CI: 4-32%) of those with and without clinical nail involvement showed enthesopathy on US examination, respectively (p = 0.54). Among PsA patients, the prevalence of enthesopathy was 30% (95% CI: 15-49%) for patients with clinical nail involvement and 35% (95% CI: 17-56%) for those without nail involvement (p = 0.71). CONCLUSION: Nail disease was associated with DIP US enthesopathy. There was a significant increased prevalence of extensor tendon enthesopathy in fingers with involved nails both in PsO and PsA, although no association was found between nail involvement and extensor tendon enthesopathy at patients' level. These features might support the nail-entheseal pathogenesis theory at DIP level.

Validity of a simple videogrammetric method to measure the movement of all hand segments for clinical purposes.

Hand movement measurement is important in clinical, ergonomics and biomechanical fields. Videogrammetric techniques allow the measurement of hand movement without interfering with the natural hand behaviour. However, an accurate measurement of the hand movement requires the use of a high number of markers, which limits its applicability for the clinical practice (60 markers would be needed for hand and wrist). In this work, a simple method that uses a reduced number of markers (29), based on a simplified kinematic model of the hand, is proposed and evaluated. A set of experiments have been performed to evaluate the errors associated with the kinematic simplification, together with the evaluation of its accuracy, repeatability and reproducibility. The global error attributed to the kinematic simplification was 6.68°. The method has small errors in repeatability and reproducibility (3.43° and 4.23°, respectively) and shows no statistically significant difference with the use of electronic goniometers. The relevance of the work lies in the ability of measuring all degrees of freedom of the hand with a reduced number of markers without interfering with the natural hand behaviour, which makes it suitable for its use in clinical applications, as well as for ergonomic and biomechanical purposes.

Reconstrução tardia na mão traumatizada com perda de múltiplos dedos / Late reconstruction of a traumatized hand with loss of multiple fingers

As lesões mutilantes de mão são um desafio para o cirurgião de mão e o paciente. O cirurgião deve tomar decisões desde o debridamento inicial, escolhendo quais dedos e articulações serão preservadas e uso apropriado das partes a serem retiradas. A reconstrução tardia é a segunda parte dessa difícil tarefa. Dificuldade que se atribui à particularidade de cada lesão, do grande número de possibilidades de tratamento e seus diversos níveis de complexidade que devem ser adequados à necessidade e motivação pessoal de cada paciente. Este relato de caso apresenta uma reconstrução tardia de mão com perda de indicador e dedo médio com transplante de articulação metacarpofalângica de indicador para função de interfalangeana proximal de dedo médio.

Mutilating hand injuries are a challenge to both the hand surgeon and the patient. The surgeon must make decisions ranging from the initial debridement to which fingers and joints will be preserved and the appropriate use of the parts to be removed. Late reconstruction constitutes the second part of this difficult task. The difficulty attributed to the characteristics of each lesion, the large number of treatment possibilities, and the different levels of complexity must be adapted to the personal needs and motivation of each patient. This case report describes a late hand reconstruction with index and middle finger loss, using metacarpophalangeal joint transplantation of the index finger to gain the proximal interphalangeal function of the middle finger.