Motion Of Metacarpophalangeal Joint Research Articles

A Two-stage Surgery for Completely Degloving Injury of Multiple Fingers: a Retrospective Cohort Study

PurposeThe completely degloving injury of multiple fingers is a challenging clinical problem. Based on our technical experience, a novel two-stage surgery of abdominal hypodermal pocket followed by separation and full thickness skin grafting was conducted. MethodsFrom January 2017 to August 2020, 7 cases (17 fingers) of degloving injury of multiple whole fingers who were treated in a two-stage fashion; an emergency first stage surgery of abdominal hypodermal pocket embedding and a second stage surgery (4 weeks later) of full thickness skin grafting, were retrospectively studied. The results were evaluated according to the patient subjective evaluation, static two-point discrimination and disabilities of the arm, shoulder and hand (DASH) scores and active range of motion (ROM) of metacarpophalangeal (MP) and proximal interphalangeal (PIP) joints. ResultsAll seven cases healed successfully, although two cases experienced distal phalanx necrosis. The affected fingers recovered with a good appearance and soft texture and the results were either satisfying or acceptable for all participants. The active ROM of MP joint ranged from 55° to 64° with an average of 59.5° three months postoperatively and ranged from 70° to 81° with an average of 77.2° six months postoperatively, while the active ROM of PIP joint ranged from 58° to 69° with an average of 64.1° three months postoperatively and from 76° to 86° with an average of 81° six months postoperatively. One year postoperatively, the static two-point discrimination ranged from 7 to 10mm with an average of 8.6mm and DASH scores ranged from 25 to 42 with an average of 37. ConclusionA novel two-stage surgery of abdominal hypodermal separated pockets followed by full thickness is an effective and worthwhile option for treating the completely degloving injury of multiple fingers.

The Validity and Reliability of a Smartphone Application for Measuring Wrist and Metacarpophalangeal Joint Motion.

Background Accurate measurement of the range of motion (ROM) is crucial for guiding upper extremity rehabilitation. Inaccurate measurements can mislead clinicians and harm patient compliance. This study aimed to evaluate the validity and reliability of a smartphone application (Angulus) for measuring wrist and metacarpophalangeal (MCP) joint ROM. Methodology This study included 64 volunteers with no prior wrist injuries. Thewrist flexion/extension, radial/ulnar deviation, and MCP joint flexion/extension ROM were assessed by an experienced physiotherapist (Assessor 1) using the Angulus and a standard two-arm goniometer. The validity of Angulus was evaluated by correlating it with the goniometer measurements using the Pearson correlation coefficient. For the reliability analysis, an inexperienced biomedical engineer (Assessor 2) performed the same measurements using Angulus twice in different sessions, in addition to Assessor 1. The intra-rater and inter-rater reliability were tested using the intraclass correlation coefficient. Results The mean age of the participants was 29.5 ± 8.2 years, with 62% being female. The validity of the Angulus app measurements was indicated by the adequate to excellent correlation between the Angulus and goniometer measurements (ranging from 0.44 to 0.81). The intra-rater reliability of the Angulus app was excellent for Assessor 1 (ranging from 0.76 to 0.90) and adequate to excellent for Assessor 2 (ranging from 0.71 to 0.88). The inter-rater reliability of Angulus was excellent (ranging from 0.91 to 0.96). Conclusions Angulus is a valid and reliable method to measurethe wrist and MCP joint ROM.

ExoMechHand prototype development and testing with EMG signals for hand rehabilitation

Rehabilitation is a major requirement to improve the quality of life and mobility of patients with disabilities. The use of rehabilitative devices without continuous supervision of medical experts is increasing manifold, mainly due to prolonged therapy costs and advancements in robotics. Due to ExoMechHand's inexpensive cost, high robustness, and efficacy for participants with median and ulnar neuropathies, we have recommended it as a rehabilitation tool in this study. ExoMechHand is coupled with three different resistive plates for hand impairment. For efficacy, ten unhealthy subjects with median or ulnar nerve neuropathies are considered. After twenty days of continuous exercise, three subjects showed improvement in their hand grip, range of motion of the wrist, or range of motion of metacarpophalangeal joints. The condition of the hand is assessed by features of surface-electromyography signals. A Machine-learning model based on these features of fifteen subjects is used for staging the condition of the hand. Machine-learning algorithms are trained to indicate the type of resistive plate to be used by the subject without the need for examination by the therapist. The extra-trees classifier came out to be the most effective algorithm with 98% accuracy on test data for indicating the type of resistive plate, followed by random-forest and gradient-boosting with accuracies of 95% and 93%, respectively. Results showed that the staging of hand condition could be analyzed by sEMG signal obtained from the flexor-carpi-ulnaris and flexor-carpi-radialis muscles in subjects with median and ulnar neuropathies.

Differences between trapeziometacarpal arthrodesis and trapeziectomy with ligament reconstruction for the treatment of trapeziometacarpal osteoarthritis: a systematic review and meta-analysis.

The optimal management of trapeziometacarpal (TMC) osteoarthritis remains controversial. This meta-analysis assessed the subjective and objective outcomes of trapeziometacarpal arthrodesis (TMA) versus trapeziec-tomy with ligament reconstruction (LRTI). The PubMed, Cochrane Library, Embase, Web of science data-bases were searched from inception to June 30, 2022. Keywords included "trapeziometacarpal osteoarthrosis", "trapeziometacarpal arthrodesis" and "trapeziectomy with ligament reconstruction". Randomized controlled trials (RCTs) and controlled clinical trials (CCTs) including patients treated for TMC osteoarthritis were included. The subjective outcomes visual analogue scale (VAS) , Patient-Rated Wrist and Hand Evaluation (PRWHE), Disabilities of arm, shoulder and hand (DASH) scores, Kapanji scores, objective outcomes total interphalangeal (IP) and metacarpophalangeal (MCP) joint motion, palmar abduction, grip strength, tip, key pinch strength and complications were extracted. The methodological quality of each was assessed in- dependently. Meta-analysis was performed for comparative trials. From the 5 included studies (2 RCTs, 3 CCTs), 208 cases were divided into TMA group (n = 107) and LRTI group (n =101) groups. Compared with the TMA group, PRWHE, tip pinch strength and palmar abduction was better in the LRTI group. There was no statistical difference in DASH score, VAS, kapandji score, grip strength, key pinch strength, total IP joint motion, total MCP joint motion and complications. The LRTI group had more obvious advantages in term of PRWHE, tip pinch strength and palmar abduction. Moreover, there was no statistical difference in DASH score, VAS, kapandji score, grip strength, key pinch strength, total IP joint and total MCP joint motion and complications. Therefore, we concluded LRTI was more recommendable for more management of TMC osteoarthritis. Certainly, high-quality studies are required in long-term follow-up.

Plate fixation with a single incisional approach in adjoining two metacarpal shaft fractures

Purpose: Multiple metacarpal shaft fractures are higher-energy injuries than single metacarpal shaft injuries and are considered relatively unstable because reduction is easily lost after splinting. However, few studies have been published on operative treatment because these fractures are rare. The aim of this study was to analyze the characteristics of this rare type of fracture and report the surgical outcomes. Methods: Medical records of patients with adjacent metacarpal shaft fractures who underwent surgery were retrospectively analyzed. In total, 20 cases were included in this study. A single longitudinal incision was made at the middle of the web space of affected metacarpal bones. Fractures were fixed using a plate and screws. The clinical results were evaluated by determining the metacarpophalangeal joint range of motion, Disabilities of the Arm, Shoulder, and Hand (DASH) scores, and hand grip strength at the final follow-up. Results: Among the patients included, there were fifteen male and five female patients. Their mean age was 41.2 years. The average range of motion of metacarpophalangeal joints was 78.1°. The average DASH score was 6.5. The average hand grip strength was 92.4% compared to the unaffected side. The mean time to union was 7.5 weeks. There were no cases of complications, such as soft tissue infections, joint stiffness, or extensor tendon injuries. Conclusion: Plate fixation through a single incisional approach performed for adjacent metacarpal shaft fractures showed satisfactory results. This could be a recommendable approach for two unstable adjoining metacarpal shaft fractures.

The Optimum Size of K-Wires for Fifth Metacarpal Neck Fractures: Double 1.6 mm K-Wires Antegrade Intramedullary Nailing Technique

Objective: Previous researches did not pay significant attention to the 5th metacarpal’s intramedullary diameter. This research aims to determine the optimal K-wires for 5th metacarpal neck fractures based on the narrowest part of 5th metacarpal. Methods: We retrospectively studied 31 patients with fifth metacarpal neck fractures. All patients underwent Intramedullary (IM) nailing surgery with two 1.6 mm K-wires. The narrowest part of the fifth metacarpal was measured preoperatively based on CT scan. Quick-DASH was assigned to be the primary outcome, pain, satisfaction, motor function and complications were also recorded. Results: Well reductions were observed in all patients. QuickDASH sore was median 0 with the range of 0-32, pain score was median 0 with the range of 0-2, VAS satisfaction was median 5 with the range of 3-5 at the endpoint. Grip strength, metacarpophalangeal joint and total active motion were improved immediately after operation. Two patients remained persistent paresthesia, and three patients experienced persistent pain at the endpoint with the VAS score of 1, 2, 2. Conclusion: The use of double 1.6 mm K-wires antegrade intramedullary nailing could be an optimum option for patients with fifth metacarpal neck fractures.

Secondary Thumb Reconstruction via Ectopic Banking of Bony Phalanges From a Nonreplantable Amputated Thumb: A Follow-Up Study

This study aimed to evaluate the radiological and functional results of secondary thumb reconstruction via ectopic banking of bony phalanges from a nonreplantable amputated thumb. Thumb reconstruction was performed using the bony phalanges from a nonreplantable amputated thumb that were ectopically banked in a subcutaneous pocket. A wraparound flap was harvested from the ipsilateral great toe and wrapped around the bone graft. After surgery, the results were assessed in terms of infection, range of motion, bone union of the graft, and signs of osseous resorption of the reconstructed thumb. Fifteen patients underwent secondary thumb reconstruction using this technique between January 2003 and October 2018. Ten patients were followed up for at least 6 months (6 months to 9 years) and were included in this study. All wraparound flap transfers were viable. No bone graft infection was observed. In the 6 cases in whom the interphalangeal joint was not fused, the interphalangeal joint motion ranged from 5° to 60° with an average of 35.0° ± 15.1°. The metacarpophalangeal joint motion ranged from 5° to 66°, with an average range of motion of 48.2° ± 23.6° for the cases in whom the joint was not fused. In 8 of the 10 patients, the time of bone ectopic banking was within 10 days. In these patients, bone union with no osseous atrophy was observed. In 2 patients whose phalanx was banked for more than a month, different degrees of bone resorption of the grafted phalanx were evident after transplantation, although no further treatment was required. Bony phalanges from a nonreplantable amputated thumb can be ectopically banked and used for secondary reconstruction of the thumb. The duration of banking before thumb reconstruction should be no more than 2 weeks. Therapeutic V.

Functional improvement by body-powered 3D-printed prosthesis in patients with finger amputation

Rationale:The most common upper limb amputations are finger amputations, resulting in functional limitations that lead to problems with activities of daily living or job loss. For many years, prosthetic options for finger amputations have been limited to passive prostheses. In many countries including South Korea, body-powered finger prostheses have rarely been prescribed due to high cost, lack of experience of physicians and prosthetists, low interest and no coverage by insurance benefits. We report 2 cases of work-related finger amputations in patients who received body-powered 3D-printed finger prostheses.Patient concerns and diagnosis:Patient 1 was a 25-year-old woman with second and third finger amputations at the proximal interphalangeal level. Patient 2 was a 26-year-old man who sustained a second finger amputation at proximal interphalangeal level.Interventions:We created body-powered 3D-printed finger prostheses that mimicked distal interphalangeal joint motion through patient-driven metacarpophalangeal joint motion using a string connected to a wrist strap and a linkage system. The source code “Knick Finger” was downloaded from e-NABLE.Outcomes:After 1 month of prosthesis training, both patients were satisfied with the prostheses and showed improved performance in patient-derived goals of cooking (patient 1) and typing on a computer (patient 2).Lessons:Over the past decade, significant advances have been made in 3D-printed prosthetics owing to their light weight, low cost, on-site fabrication, and easy customization. Although there are still several limitations in the general application of 3D-printed finger prostheses, our study suggests that for patients with finger amputations, body-powered 3D-printed finger prostheses have high potential as an additional prosthetic option to the existing passive cosmetic prostheses.

Changes in the Functional Range of Motion of the Thumb Metacarpophalangeal Joint After Trapeziometacarpal Arthrodesis for Patients With Advanced Trapeziometacarpal Osteoarthritis

Advanced-stage trapeziometacarpal (TMC) osteoarthritis of the thumb often presents with concomitant hyperextension deformity of the metacarpophalangeal (MCP) joint. Although several studies have reported simultaneous procedures to correct this deformity, the indication for these procedures remains controversial. The purpose of this study was to evaluate changes in the range of motion (ROM) of the thumb MCP joint before and after TMC arthrodesis. We evaluated the functional flexion and extension and functional ROM of the MCP joints during the performance of 10 activities of daily living tasks before and after TMC arthrodesis in 10 thumbs of 9 patients with Eaton stage III TMC osteoarthritis and hyperextension deformity of the MCP joint. The mean functional flexion of the MCP joint increased from 26° to 38°, and the mean functional extension of the MCP joint decreased from 16° to 5° of hyperextension. There was no change in the mean total arc of functional ROM of the MCP joint. The MCP joint motion shifted from extension to flexion after TMC arthrodesis, and the total arc of functional ROM of the MCP joint was similar before and after arthrodesis. Therapeutic V.

The curative effect analysis of a modified Kirschner wires and locking plate internal fixation method for the fifth metacarpal neck fracture

PurposeTo evaluate the efficacy of a modified internal fixation method for the treatment of fifth metacarpal neck fracture.MethodsFrom March 2018 to December 2019, 12 patients with the fifth metacarpal neck fractures of the hands were treated with the Kirschner wires and locking plate internal fixation method. Each patient’s gender, age, dominant hand, injured hand, trauma mechanism, preoperative and postoperative deformity (angulation and the length of the fifth metacarpal), the range of motion of the metacarpophalangeal joint and grip strength of each side, the time of return to work, and follow-up time were recorded and calculated.ResultsThe mean follow-up time was 16.8 months, and the angulations of preoperative and postoperative deformity were 40.0 ± 3.7°and 17.6 ± 1.7°, respectively. The length of the fifth metacarpals of preoperative and postoperative deformity were 51.5 ± 2.1 mm and 60.0 ± 1.8 mm, respectively. At the last follow-up, the range of motion of the fifth metacarpophalangeal joint of the injured side and the contralateral side were 84.3 ± 3.6°and 86.5 ± 2.0°, and the grip strength of the injured side and the contralateral side were 74.8 ± 6.1 LB and 78.6 ± 8.3 LB, respectively, without statistically significant differences. QDASH score was 2.0 ± 1.0, and the time of return to work was 6.0 ± 0.7 weeks.ConclusionThe modified internal fixation method is one of the alternative treatments for the fifth metacarpal neck fracture with good curative effects.

Modified dynamic high-frequency ultrasound-guided needle aponeurotomy for Dupuytren’s contracture

The aim of this report was to introduce the use of modified dynamic high-frequency ultrasound-guided needle aponeurotomy for Dupuytren’s contracture. From January 2014 to February 2019, the technique was used in 42 consecutive patients who suffered from Dupuytren’s contracture: 38 male and 4 female; mean age, 57 years (range, 32–80 years). Assessments comprised total active extension deficit and total active flexion of the fingers, active range of motion, Disabilities of the Arm, Shoulder and Hand (DASH) score, and EQ-5D index. Recurrence was defined as ≥20° flexion contracture. Compared to the opposite hand, preoperative total active extension deficit and total active flexion were 105° ± 32° and 221° ± 33°, respectively. The mean active range of motion of the metacarpophalangeal, proximal interphalangeal and distal interphalangeal joints was 42° ± 24°, 37° ± 26° and 62° ± 14°, respectively. Mean follow-up was 27 months (range, 24–35 months). There were no cases of tendon rupture or neurovascular injury. Total active extension deficit and total active flexion at the final follow-up were 17° ± 11° and 225° ± 32°, respectively. The mean active range of motion of metacarpophalangeal, proximal interphalangeal and distal interphalangeal joints was 73° ± 28°, 89° ± 24° and 63° ± 16°, respectively. The pre- and post-operative DASH scores were 18 ± 10 and 5 ± 2, respectively. Health-related quality of life on EQ-5D index improved from 0.72 ± 0.28 pre-operatively to 0.88 ± 0.72 post-operatively (p < 0.05). Recurrence rates in the metacarpophalangeal joint and proximal interphalangeal joint were 7% and 11%, respectively. The modified dynamic high-frequency ultrasound-guided needle aponeurotomy is a safe and effective way to treat Dupuytren’s contractures. Ultrasound visualization ensures that the cords can be completely transected. Dynamic ultrasound decreases the risk of iatrogenic injury to the neurovascular bundles and tendons, and decreases the recurrence rate. Level of evidenceTherapeutic study, level IV.

AMRTA-X: Grasp Kinematic Analysis during Myoelectric Prehension Orthosis and Body Powered Prehension Orthosis's Usage on Brachial Plexus Injury Patients

Brachial Plexus Injury (BPI) results in decreased motor function in upper extremity and leads to reduced hand grasping movement. Orthotic prehension is designed to create artificial grasp movements in paralyzed hand. This study was to compare grasp kinematic improvement between body powered and myoelectric prehension orthosis usage in patients with BPI. This study was a single group without control and post test with experimental study. The subjects of the study (n = 11) were brachial plexus injury patients with non-functional hand strength. Joint motion and angular velocity of metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joint of index finger were evaluated. There was an improvement in joint motion and angular velocity after both orthosis usage. Joint motion in MCP and PIP, Angular velocity in MCP were not significantly different between myoelectric and body powered and myoelectric prehension orthosis usage. PIP angular velocity improvement were better after body powered prehension orthosis usage (p= 0.03).In conclusion, body powered and myolectric prehension orthosis usage improved kinematic parameter of index finger’s MCP and PIP joint. PIP angular velocity was better after body powered prehension orthosis usage.

Trapeziectomy for trapeziometacarpal osteoarthritis.

AimsThe objective of this systematic review was to describe trapeziectomy outcomes and complications in the context of osteoarthritis of the base of the thumb after a five-year minimum follow-up.MethodsPreferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used to guide study design, and 267 full-text articles were assessed for eligibility. After exclusion criteria application, 22 studies were included, involving 728 patients and 823 trapeziectomies. Outcomes included pre- and postoperative clinical and radiological characteristics. Complications and revisions were recorded.ResultsAll the studies reported good results regarding pain and range of motion at the last follow-up of 8.3 years (5 to 22); the mean satisfaction rate was 91% (84% to 100%). It was difficult to assess the impact on metacarpophalangeal joint motion in extension with contrary results. The key pinch returned to its preoperative values, whereas tip pinch showed a modest improvement (+14%), with a mild improvement found in grip strength (+25%) at the last follow-up. The mean progressive trapezial collapse was 48% (0% to 85%) and was not correlated with pain, grip strength, or satisfaction. The most represented complications were linked to tendons or nerves affected during additional procedures to stabilize the joint (11.6%; n = 56). Mechanical complications included symptomatic scapho-M1 impingement (3.1%; n = 15/580), leading to nine surgical revisions out of 581 trapeziectomies. Meta-analysis was not possible due to study heterogeneity and limited data.ConclusionAfter a minimum five-year follow-up, trapeziectomy achieved high patient satisfaction and pain relief. However, strength seemed to be deteriorating with detrimental consequences, but this did not correlate with trapezial collapse. The issues related to underestimating mechanical complications and varying degrees of success should be highlighted in the information given to patients. Evidence-based analyses should help the surgeon in their decision-making.Cite this article: Bone Jt Open 2021;2(3):141–149.

Using Reinforcement Learning to Estimate Human Joint Moments From Electromyography or Joint Kinematics: An Alternative Solution to Musculoskeletal-Based Biomechanics.

Reinforcement learning (RL) has potential to provide innovative solutions to existing challenges in estimating joint moments in motion analysis, such as kinematic or electromyography (EMG) noise and unknown model parameters. Here, we explore feasibility of RL to assist joint moment estimation for biomechanical applications. Forearm and hand kinematics and forearm EMGs from four muscles during free finger and wrist movement were collected from six healthy subjects. Using the proximal policy optimization approach, we trained two types of RL agents that estimated joint moment based on measured kinematics or measured EMGs, respectively. To quantify the performance of trained RL agents, the estimated joint moment was used to drive a forward dynamic model for estimating kinematics, which was then compared with measured kinematics using Pearson correlation coefficient. The results demonstrated that both trained RL agents are feasible to estimate joint moment for wrist and metacarpophalangeal (MCP) joint motion prediction. The correlation coefficients between predicted and measured kinematics, derived from the kinematics-driven agent and subject-specific EMG-driven agents, were 98% ± 1% and 94% ± 3% for the wrist, respectively, and were 95% ± 2% and 84% ± 6% for the metacarpophalangeal joint, respectively. In addition, a biomechanically reasonable joint moment-angle-EMG relationship (i.e., dependence of joint moment on joint angle and EMG) was predicted using only 15 s of collected data. In conclusion, this study illustrates that an RL approach can be an alternative technique to conventional inverse dynamic analysis in human biomechanics study and EMG-driven human-machine interfacing applications.

Range of Motion of Metacarpophalangeal and Proximal Interphalangeal Joints in Patients with Systemic Sclerosis Treated with Adipose Derived Stromal Vascular Fraction

The limitation of digital mobility very commonly affects patients with Systemic Sclerosis (SSc). In this study, we aimed to report the changes in the active Range of Motion (ROM) of the Metacarpophalangeal (MCP) and Proximal Interphalangeal (PIP) joints after local injection of the Adipose-Derived Stromal Vascular Fraction (ADSVF).

The biomechanics of knuckle-walking: 3-D kinematics of the chimpanzee and macaque wrist, hand and fingers.

The origin and evolution of knuckle-walking has long been a key focus in understanding African ape, including human, origins. Yet, despite numerous studies documenting morphological characteristics potentially associated with knuckle-walking, little quantitative three-dimensional (3-D) data exist of forelimb motion during knuckle-walking. Nor do any comparative 3-D data exist for hand postures used during quadrupedalism in monkeys. This lack of data has limited the testability of proposed adaptations for knuckle-walking in African apes. This study presents the first 3-D kinematic data of the wrist, hand and metacarpophalangeal joints during knuckle-walking in chimpanzees and in macaques using digitigrade and palmigrade hand postures. These results clarify the unique characteristics of, and commonalities between, knuckle-walking and digitigrady/palmigrady in multiple planes of motion. Notably, chimpanzees utilized more wrist ulnar deviation than any macaque hand posture. Maximum extension of the chimpanzee wrist was slight (5-20deg) and generally overlapped with macaque digitigrady. Metacarpophalangeal joint motion displayed distinct differences between digits in both species, likely related to the timing of force application. These data also reveal that maximum metacarpophalangeal extension angles during knuckle-walking (26-59deg) were generally higher than previously considered. In macaques, maximum metacarpophalangeal extension during digitigrady and palmigrady overlapped for most digits, highlighting additional complexity in the interpretation of skeletal features that may be related to limiting metacarpophalangeal motion. Most importantly, however, these new 3-D data serve as a fundamental dataset with which evaluation of proposed musculoskeletal adaptations for knuckle-walking can be tested.

The fifth metacarpal neck fracture treated by closed reduction and intramedullary fixation with antegrade Kirschner wire plus rod rotation technique

Objective To assess the clinical effects of closed reduction and intramedullary fixation with antegrade Kirschner wire plus rod rotation technique in the treatment of the fifth metacarpal neck fracture. Methods In this retrospective study, 26 patients with the fifth metacarpal neck fracture were treated by closed reduction and intramedullary fixation with antegrade Kirschner wire plus rod rotation technique at Department of Orthopaedics, Central Hospital of Karamay from August 2015 to October 2017. They were 23 males and 3 females, aged from 12 to 53 years with an average age of 25.2 years. In the intramedullary nailing, a Kirschner wire pre-bent by 10° to 15° was inserted from the base of the fifth metacarpal into the medullary canal before closed reduction. After satisfactory reduction was achieved, the Kirschner wire was inserted across the fracture site into the metacarpal head for further reduction and fixation using rod rotation technique. After operation, a plaster was applied to protect the fixation for 2 weeks. Functional exercise was started after removal of the plaster. The Kirschner wire was not removed under local anaesthesia at the outpatient department until about 10 to 16 weeks postoperation when X-ray showed fracture healing. Records of their operation time, head/shaft angle of the fifth affected metacarpal, active range of motion of the metacarpophalangeal joints and Total Active Movement (TAM) of hand function at the last follow-up were collected. Results Their operation time averaged 21 minutes (from 12 to 35 minutes). Anatomical reduction was achieved in 23 cases but not in 3 ones whose metacarpal head/shaft angle and alignment were obviously improved. Follow-ups for 6 to 29 months (average, 15.8 months) showed all the patients obtained solid fracture healing with no infection or delayed fracture healing. The head/shaft angle was improved significantly from preoperative 61.2°±11.2° to postoperative 14.7°±3.5° (P 0.05). The active range of motion of the metacarpophalangeal joint was 89.3°±4.2° after fixation removal, not significantly different from that of the healthy side (90.7°±1.5°) (P>0.05). According to TAM scores at the last follow-up, 22 cases were rated as excellent, 3 as good and one as fair. Conclusion In the treatment of the fifth metacarpal neck fracture, closed reduction and intramedullary fixation with antegrade Kirschner wire plus rod rotation technique is effective, because it is simple and limitedly invasive, and leads to limited complications, low costs and secondary reduction. Key words: Metacarpal bone; Fracture fixation, intramedullary; Bone nail; Fifth metacarpal neck fracture; Rod rotation

Effect of Fatigue on Equine Metacarpophalangeal Joint Kinematics—A Single Horse Pilot Study

The objective was to validate a scientific method for characterizing equine metacarpophalangeal joint (MCPJ) motion in the nonfatigued and fatigued states using a single horse at trot, slow canter, and fast canter. One healthy Thoroughbred gelding exercised on a treadmill to exhaustion (fatigued state) (heart rate >190 BPM and blood lactate >10 mmol/L) while bilateral MCPJ angular data were acquired using electrogoniometry. Blood lactate and heart rate reflected transition from nonfatigued to fatigued states with increasing exercise duration and treadmill speed. Electrogoniometry consistently demonstrated: increase in mean MCPJ maximum extension angle with onset of fatigue; altered extension and flexion angular velocities with onset of fatigue; and increasing stride duration and decreasing stride frequency with onset of fatigue. The method allowed a preliminary but comprehensive characterization of the dynamic relationship between MCPJ kinematics and fatigue, prompting the need for multisubject studies that may enhance our ability to moderate exercise-related distal limb injury in equine athletes.

Application of accelerated rehabilitation surgery concept in the treatment of metacarpal fractures with absorbable rods

Objective To explore the clinical efficacy of absorbable rod in the treatment of metacarpal fractures under the guidance of accelerated rehabilitation surgery concept. Methods From August 2016 to August 2018, 53 patients with long oblique and spiral metacarpal fractures were treated with absorbable rod by fixation perpendicular to the fracture line. The patients were divided into observation group and control group according to whether they were treated with the concept of accelerated rehabilitation surgery during perioperative period or not. There were 24 cases in the observation group (28 places) and 29 cases in the control group (31 places). The visual analogue scale (VAS) on the first day after operation, the time when the active range of motion of metacarpophalangeal joint returned to normal, the time of fracture healing and the functional evaluation results of the injured hand at the last follow-up were compared between the two groups. Results All the patients were follow-up for 1 to 12 months with an average of 9.2 months. All the incisions achieved primary healing and all the fractures were healed. On the first day after operation, VAS and the recovery time of metacarpophalangeal joint activity in the observation group were (2.64±0.81) points and (19.35±2.12) days, respectively, which were significantly lower than those in the control group (3.42±1.13) points and (28.63±1.31) days. The differences were statistically significant (t=-2.920, -14.665, P 0.05). There was no significant difference in hand function evaluation between the two groups at the last follow-up (χ2=0.045, P>0.05). Conclusion The technique of absorbable rod by fixation perpendicular to the fracture line for long oblique or spiral metacarpal fractures is a safe and effective surgical method. With the guidance of accelerated rehabilitation surgery concept, hand function can be better restored and satisfactory clinical efficacy can be obtained. Key words: Metacarpal bones; Fractures,bone; Absorbable rod; Accelerated rehabilitation surgery

The treatment of Wassel type VI thumb duplications with on-top-plasty

Objective To investigate the clinical efficacy and intraoperative attention of on-top-plasty technique for treatment of Wassel type Ⅵ thumb duplications. Methods From April 2012 to June 2018, 8 cases of Wassel typeⅥ thumb duplications were treated by on-top-plasty. Postoperative objective evaluation included whether the thumb was deflected, passive range of motion of the metacarpophalangeal (MP) joint, interphalangeal (IP) joint and the first carpometacarpal (CMC1st) joint. Radiographic examination was used to evaluate the force line of thumb, bone healing time and the development of the first metacarpal bone. Subjective evaluation was completed by the parents of the patients with functional and appearance satisfaction questionnaire. Results The follow-up period ranged from 2 to 36 months, with an average of 19.5 months. No deflection of thumbs occurred. The range of passive motion of MP, IP and CMC joints was not significantly decreased compared with the healthy side. Postoperative X-ray showed that the force line of the first metacarpal bone was good in 7 cases and malunion in 1 case. The bone healing time ranged from 5 to 7 weeks with an average of 6.2 weeks. There was no retardation in the development of the first metacarpal bone. The function of subjective satisfaction survey was excellent in 4 cases, good in 3 cases, fair in 1 case and the appearance was excellent in 4 cases, good in 2 cases, fair in 1 case, poor in 1 case. Conclusion On-top-plasty technique is an effective method to treat Wassel typeⅥ thumb duplications. The full preoperative evaluation, different incisions according to the contracture of thumb web, clear identification of anatomical structures and protection of vascular pedicles are the basic guarantee for restoring thumb function. Key words: Hand deformities, congenital; Treatment outcome; Thumb duplications; Wassel type Ⅵ; On-top-plasty