Metacarpophalangeal Research Articles

Arthroscopic Management of Metacarpophalangeal Joint Synovial Chondromatosis

AbstractSynovial chondromatosis is a rare condition where cartilaginous nodules form within the synovium, which can detach and cause loose bodies within the joint. While it typically affects larger joints, involvement of the metacarpophalangeal (MCP) joints is rarely described. We report the case of a 42-year-old female patient who had a slow-growing mass in her right third MCP (MCP III) joint, associated with limited finger motion, swelling, and pain. The diagnosis was confirmed using imaging studies. The patient underwent arthroscopic excision of multiple tumors and synovectomy via dorsal radial and ulnar MCP III portals. Postoperatively, there was rapid improvement in hand function, including normal and pain-free range of motion. This case highlights the benefits of arthroscopic management for synovial chondromatosis in the MCP joint, as it offers advantages like minimal invasiveness, reduced tissue damage, faster recovery times, and lower infection risk compared with traditional open methods.

Effects of wrist and finger posture on finger independence

Intended actions of one finger produce involuntary movement or force in other fingers. Mechanical and neural factors limit finger independence. The interplay between anatomical factors, wrist and finger postures, and finger independence remain unclear. The purpose of this study was to determine the effects of wrist and metacarpophalangeal (MCP) posture on involuntary finger forces and extensor digitorum (ED) activity. Twenty participants performed submaximal isometric finger extensions in three wrist positions (30° extension, neutral, and 30° flexion) and two MCP postures (straight and 90° flexion). Involuntary index finger force increased with MCP flexion, suggesting the importance of intertendinous connections in finger independence. Consistent with previous research, ED activity was generally higher in wrist extension than neutral and flexed postures. Understanding the role of passive properties within the hand may help us improve finger rehabilitation strategies.

Detecting New Erosions in Rheumatoid Arthritis over One Year - Radiography and High-Resolution Computed Tomography of Finger Joints.

To compare the number of new erosions in two metacarpophalangeal (MCP) joints over one year assessed by high-resolution peripheral quantitative computed tomography (HR-pQCT) and conventional radiography (CR). Furthermore, to estimate the diagnostic accuracy of erosive progression by CR with HR-pQCT as the reference standard. Paired sets of image data were available from patients with RA (n=310), who underwent HR-pQCT and CR, including the 2nd and 3rd MCP joints only of the dominant hand at baseline and at the one-year follow-up. Erosion number was determined using HR-pQCT and CR. Erosive volume was estimated from segmented HR-pQCT images, and erosion scores were obtained by the Sharp/van der Heijde method from CR. Erosive progression was defined as an increase in total erosion number or a study-specified increase in total erosive volume or total erosion score. At baseline, 250 erosions were identified by CR compared to 1864 erosions by HR-pQCT. After one year, 3 new erosions were detected by CR compared to 66 new erosions by HR-pQCT. Erosive progression was identified in 40 patients using HR-pQCT and in 3 patients using CR. With HR-pQCT as reference, CR had a sensitivity of 2.5% (95% CI: 0.1-13.2%) and a specificity of 99.3% (95% CI: 97.3-99.9%) for detecting erosive progression. HR-pQCT identified more than 20 times the number of new erosions, and more than 10 times as many patients with erosive progression than CR. HR-pQCT is a sensitive tool for monitoring new erosions and erosive progression over one year in RA.

Study protocol for a multicenter non-inferiority randomized controlled trial to assess functional outcomes and cost-effectiveness of a primarily non-operative treatment strategy with cast immobilization versus immediate operative treatment followed by cast immobilization for patients with complete ulnar collateral ligament ruptures, including Stener lesions: MUSCAT study

BackgroundGuidelines recommend operative treatment followed by cast immobilization for acute complete ulnar collateral ligament (UCL) ruptures, including Stener lesions. This recommendation is based on expert opinion, anatomic theories, and low-quality observational case series. High-quality studies comparing non-operative treatment to operative treatment are lacking. We hypothesize that primarily non-operative treatment with cast immobilization (cast immobilization) is non-inferior regarding functional outcome and carries concomitant lower costs compared with immediate operative treatment followed by cast immobilization (operative treatment) for complete UCL ruptures, including Stener lesions.MethodsThis is a multicenter randomized controlled non-inferiority trial (RCT) including patients of 18 years and above, requiring treatment for an acute complete UCL rupture, including Stener lesions. Patients are randomized to cast immobilization or operative treatment followed by cast immobilization. Immobilization consists of 4 weeks of a non-removable cast around the metacarpophalangeal (MCP) and carpometacarpal (CMC) joint of the thumb in a neutral position, followed by a removable cast for 4 weeks for both groups. Patients in the cast immobilization group are re-evaluated 2 to 3 weeks after the start of cast immobilization to examine thumb stability and determine if secondary surgery is required. In case of persistent laxity, secondary surgery is required. The primary outcome is hand function expressed as the Michigan Hand outcome Questionnaire (MHQ) at 6 months (from injury to 6 months after).DiscussionIf cast immobilization is non-inferior to operative treatment, the proposed treatment strategy will reduce patient burden by preventing surgery. It is expected that about one in ten patients who started with cast immobilization will need secondary surgery during re-evaluation. As a result, completion of the treatment will take longer for these patients compared to patients who received immediate operative treatment.Trial registrationCentral Committee on Research Involving Human Subjects (CCMO), NL78886.100.21; registered on 4 October 2021. Medical Research Ethics Committees United (MEC-U), R21.006; registered on 09 December 2021. Clinical Trial register, identifier: NCT05291260; retrospectively registered on 22 March 2022.

Surgical Management of Early Metacarpophalangeal Joint Silicone Implant Fracture in Patient With Rheumatoid Arthritis

Introduction: Metacarpophalangeal (MCP) joint arthroplasty is a common treatment modality to correct ulnar drift, pain, and functional deficits in patients with rheumatoid arthritis, an autoimmune condition targeting the synovium of joints. While silicone MCP joint implants are susceptible to revision in the long term, there is a lack of literature discussing their early breakage. The present case illustrates silicone implant fracture only 10 weeks after MCP arthroplasty—the first instance in the literature to the authors’ knowledge. Materials and Methods: The patient is a 64-year-old female with stage 4 rheumatoid arthritis who underwent right index and middle finger MCP joint arthroplasties using 0-degree silicone implants, radial sagittal band imbrication on these digits, and right ring and small finger extensor tendon centralization at the MCP joint. Results: During the 10th postoperative week, the patient presented with atraumatic middle finger pain and ulnar deviation. Imaging revealed a right middle finger MCP implant fracture at the distal stem, which underwent successful revision using a 30-degree flexed implant and index and middle extensor tendon centralization. Discussion: Nineteen months after revision surgery, the patient continues to have no pain and an improved range of motion. Ultimately, we are hopeful that the flexed silicone implant will last the patient's lifetime.

Comparing on-line continuous movement decoding with joints unconstrained and constrained based on a generic musculoskeletal model.

Human-machine interface (HMI) has been extensively developed and applied in rehabilitation. However, the performance of amputees on continuous movement decoding was significantly decreased compared with that of able-bodied individuals. To explore the impact of the absence of joint movements on the performance of HMI in rehabilitation, a generic musculoskeletal model (MM) was employed in this study to evaluate and compare the performance of subjects completing a series of on-line tasks with the wrist and metacarpophalangeal (MCP) joints unconstrained and constrained. The performance of the generic MM has been demonstrated in previous studies. The electromyography (EMG) signals of four muscles were employed as inputs of the generic MM to realize the continuous movement decoding of wrist and MCP joints. Ten able-bodied subjects were recruited to perform the on-line tasks. The completion time, the number of overshoots, and the path efficiency of the tasks were taken as the indexes to quantify the subjects' performance. The muscle activation associated with the movement was analyzed. Across all tasks and subjects, the average values of the three indexes with the joints unconstrained were 7.7 s, 0.59, and 0.38, respectively, while those with the joints constrained were 17.86 s, 1.47, and 0.22, respectively. The results demonstrated that the subjects performed better with the wrist and MCP joints unconstrained than with those joints constrained in the on-line tasks, suggesting that the absence of joint movements can be a reason of the decreased performance of continuous movement decoding with HMIs. Meanwhile, it is revealed that the different performance on motion behaviors is caused by the absence of joint movements.

Radiographic features and subtypes of congenital thumb duplication type C3 according to Wu et al. and their potential implications for surgical management: new classification and preliminary results

BackgroundWu et al. introduced a modified radiographic system that allows classification of all forms of CTD with excellent interobserver and intraobserver reliability. No study to date has evaluated the radiographic characteristics of Wu et al. type C3 CTD with osseous attachment at the level of the metacarpal.ObjectiveThis study aimed to evaluate the radiographic features of type C3 CTD according to the system of Wu et al., to describe the different anatomical subtypes of the duplication, and to propose a categorization approach to distinguish diverse surgical strategies based on the radiographic anatomy of this specific subtype of duplication.MethodsWe performed a retrospective analysis of 215 patients (221 thumbs) diagnosed with Wu et al. type C3 CTD at our Institution between 2015 and 2021. We evaluated all CTDs by examining the alignment of the interphalangeal (IP) and metacarpophalangeal (MP) joints and by assessing the presence of abnormal hypertrophic epiphysis of the primary thumb on posteroanterior (PA) radiographs. The proposed classification system has four types: Type I with good alignment of both MP and IP joints, Type II with ulnar deviation of the MP joint, Type III with radial deviation in the MP joint and Type IV with abnormal hypertrophic epiphysis of the distal phalanx of the main thumb with ulnar deviation of the IP joint with or without ulnar deviation of the MP joint.ResultsThere were 140 male and 75 female patients with CTD (221 thumbs). There were 65 left, 144 right and 6 bilateral forms. The right-to-left, male-to-female and unilateral-to-bilateral ratios were 2.2:1, 1.9:1 and 35.8:1 respectively. The mean age at surgery was 22.3 ± 11.8 months (range, 8–80). The proposed classification system allowed the classification of all CTDs (n = 221). Specifically, 53 fingers were classified as Type I (24%), 136 as Type II (61.5%), 21 as Type III (9.5%), and 11 as Type IV (5%).ConclusionThe proposed system is based on radiographic pathoanatomy and complements that of Wu et al. by identifying four distinct subtypes of deformity. It has the potential to improve inter-professional communication and guide surgery in patients with Wu et al. type C3 CTD. However, our results are preliminary and further research is needed to validate them.Level of evidenceIII.

Numerical and Experimental Study of a Wearable Exo-Glove for Telerehabilitation Application Using Shape Memory Alloy Actuators

Hand paralysis, caused by conditions such as spinal cord injuries, strokes, and arthritis, significantly hinders daily activities. Wearable exo-gloves and telerehabilitation offer effective hand training solutions to aid the recovery process. This study presents the development of lightweight wearable exo-gloves designed for finger telerehabilitation. The prototype uses NiTi shape memory alloy (SMA) actuators to control five fingers. Specialized end effectors target the metacarpophalangeal (MCP), proximal interphalangeal (PIP), and distal interphalangeal (DIP) joints, mimicking human finger tendon actions. A variable structure controller, managed through a web-based Human–Machine Interface (HMI), allows remote adjustments. Thermal behavior, dynamics, and overall performance were modeled in MATLAB Simulink, with experimental validation confirming the model’s efficacy. The phase transformation characteristics of NiTi shape memory wire were studied using the Souza–Auricchio model within COMSOL Multiphysics 6.2 software. Comparing the simulation to trial data showed an average error of 2.76°. The range of motion for the MCP, PIP, and DIP joints was 21°, 65°, and 60.3°, respectively. Additionally, a minimum torque of 0.2 Nm at each finger joint was observed, which is sufficient to overcome resistance and meet the torque requirements. Results demonstrate that integrating SMA actuators with telerehabilitation addresses the need for compact and efficient wearable devices, potentially improving patient outcomes through remote therapy.

Therapy for Dupuytren’s Disease: Collagenase Therapy—A Long-Term Follow-Up Study

Background: Dupuytren’s disease (DD) is a systemic connective tissue disorder of the palm. It particularly affects men of Northern European or Caucasian origin over the age of 55. In addition to the classical surgical therapy via limited fasciectomy, Dupuytren’s contracture can also be treated minimally invasively. A relatively new treatment method is the use of collagenase injections (Xiapex) to reduce the contracture of the fingers. The data regarding the long-term success of this therapy are currently limited. Methods: In this monocentric retrospective study, we examined 35 patients who were treated with collagenase (Xiapex) for Dupuytren’s contracture in the long fingers. Following the manufacturer’s recommendations, the injection was administered intralesionally, and the cord was ruptured through the passive extension of the finger under local anesthesia with Mepivacain the following day. The clinical follow-up examination was conducted after an average of 5.7 years. The stages of Dupuytren’s disease were documented using the Tubiana classification. Additionally, parameters of finger extension ability, differentiated by metacarpophalangeal (MCP), and proximal interphalangeal (PIP) joints, as well as patient-specific risk parameters, were evaluated Results: The long-term results of collagenase therapy after an average of 5.7 years showed a significant improvement in the contracture of the affected fingers. In the MCP joints, the flexion contracture decreased from 42° to 17° (p ≤ 0.001), and in the PIP joints, it decreased from 56° to 33° (p ≤ 0.001). The primary recurrence rate was 11% for the MCP joints and 19% for the PIP joints, respectively. The analysis of risk factors showed a significant risk for worse long-term outcomes in patients with diabetes and those with nicotine abuse. Conclusions: Collagenase therapy for Dupuytren’s disease achieved significant long-term improvements in contracture in both MCP and PIP joints. In accordance with general risk factors for DD, patients with diabetes and those with nicotine abuse are at risk of worse long-term outcomes. Overall, it is a time-saving, low-risk, and straightforward technique for treating the disabling contracture component of this disease.

Arthrodesis as Salvage for Failed Metacarpophalangeal Arthroplasty.

Surgical management of failed metacarpophalangeal (MCP) arthroplasties includes revision arthroplasty and arthrodesis. The purpose of this study was to review the indications and outcomes of arthrodesis as a salvage procedure for failed MCP arthroplasties. This was a retrospective cohort study of all patients undergoing salvage MCP arthrodesis at a single institution from 1990 to 2020. Patient charts were reviewed for patient demographics, indication for salvage, surgical technique, revision rate, and time to radiographic union. Patient-reported outcomes, including the Michigan Hand Outcomes Questionnaire and an MCP-specific questionnaire detailing pain, functional, appearance, and patient satisfaction, were also collected. Eleven digits in 9 patients (6 women, 3 men, median age of 66) with median 36-month follow-up were included. The majority (91%) of patients also had concomitant soft tissue deformities, including joint contractures, extension lag, and collateral ligament insufficiency. The overall revision rate following arthrodesis was 45% with 3 digits requiring one revision each, and 2 digits undergoing 3 revisions. The overall union rate was 91% with median time to union of 4 months from most recent arthrodesis. Patient-reported outcomes obtained from 4 patients demonstrated improvements in pain and function. Despite a high revision rate of 45%, salvage MCP arthrodesis following arthroplasty has a high eventual union rate of 91% and is associated with improved pain and function based on 4 patients' experiences. Arthrodesis as a salvage procedure for failed MCP arthroplasties should be considered in patients with persistent joint instability and functionally limiting soft tissue deformities.

Microarchitectural analysis of the metacarpophalangeal joint using HR-pQCT in patients with rheumatoid arthritis: A comparison with healthy controls

ObjectiveTo investigate which joint microarchitectural parameters measured by high-resolution peripheral quantitative computed tomography (HR-pQCT) serve as imaging markers for rheumatoid arthritis (RA). MethodsThe second and third metacarpophalangeal (MCP) joints of 50 patients with RA and 50 healthy controls (HCs) (aged 50–79 years, all females) were scanned using a HR-pQCT. Joint space, trabecular bone microarchitecture, and erosion were measured and compared between RA patients and HCs. ResultsThere were no differences in joint space parameters between RA patients and HCs.For bone microarchitecture, RA patients had lower trabecular bone mineral density (127 vs. 167 mg/cm3), thinner trabecular thickness (0.20 vs. 0.21 mm), fewer trabecular number (1.49 vs. 1.55 /mm), more rod-like structure (1.68 vs. 1.23), and poorer trabecular connectivity (4.51 vs. 5.72 /mm3) than HCs.Regarding erosion, RA patients had a higher number of erosions per joint (36/100 vs. 18/100), larger volume (4.62 vs. 1.89 mm3), and longer width (2.40 vs. 1.82 mm) and longer length (2.34 vs. 1.64 mm) than HCs.Most of the erosions in HCs were <5 mm3 in volume (95 %) and located on the radial side (85 %). When erosions <5 mm3 were compared between RA patients and HCs, there were no differences in their location or morphology. ConclusionsDeterioration of bone microarchitecture and existences of erosions >5 mm3 in the MCP joints are sensitive imaging markers of RA. Erosions <5 mm3 in RA patients may include not only early pathological erosion but also physiological erosion because even HCs can have erosions <5 mm3.

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 Normal Active Range of Motion of the Index, Middle, Ring, and Little Fingers in a Sample of Indian Population.

Background The normative data for finger range of motion (ROM) are not available for the Indian population. The aim of our study was to measure the active ROM of finger joints in normal healthy volunteers in a sample of Indian population. Materials and Methods This is a prospective observational study conducted as a part of the Indian normative data project of the Indian Society for Surgery of the Hand (ISSH). The study included one participating center from four geographical regions of the country. Certified goniometers were used to measure the ROM of fingers in all centers. A standardized methodology was devised. A pilot study was done to assess the interobserver and intraobserver reliability, following which data were collected by one measurement. Results This pilot study was performed in 20 hands that showed good interobserver and intraobserver reliability correlation. A total of 390 hands were measured in four participating centers. Active flexion of metacarpophalangeal (MCP) joint was the highest in the middle finger (86.6 ± 10.4 degrees) followed by the index finger (86.0 ± 9.2 degrees), little finger (85.0 ± 8.4 degrees), and ring finger (84.2 ± 8.6 degrees). The index finger (97.2 ± 16.9 degrees) showed maximum proximal interphalangeal (PIP) joint flexion followed by the middle finger (96.2 ± 15.8 degrees), ring finger (96.0 ± 15.9 degrees), and little finger (91.8 ± 12.7 degrees). Distal interphalangeal (DIP) joint flexion increased from the index finger (81.6 ± 13.9 degrees) to the little finger (84.6 ± 12.9 degrees). The little finger MCP joint (26.3 ± 6.2 degrees) showed maximum extension followed by the index finger (25.7 ± 6.8 degrees), middle finger (24.7 ± 6.7 degrees) and ring finger (22.3 ± 7.1 degrees). The middle finger (15.6 ± 8.1 degrees) and ring finger (16.2 ± 8 degrees) had more PIP joint extension when compared to the index (13.7 ± 7.8 degrees) and little finger (13.2 ± 8.4 degrees). The ring finger (8.1 ± 6.8 degrees) and the middle finger (8.4 ± 6.9 degrees) had more DIP joint extension when compared with the index finger (6.0 ± 6.0 degrees) and the little finger (6.8 ± 6.7 degrees). Total active motion (TAM) of the middle finger (315.9 ± 31.0 degrees) was the maximum followed by the index finger (310.2 ± 27.3 degrees), ring finger (308.8 ± 29.1 degrees), and little finger (307.8 ± 25.2 degrees). Gender, body mass index (BMI), mother tongue, geographical location, and occupation were factors that had significant correlation, while no significant differences based on side, hand dominance, and age were noted. Conclusion We have reported normative data of finger ROM and TAM for the index, middle, ring, and little fingers in the Indian population. Finger ROM in the Indian population is highly variable. The observed TAM in the Indian population is higher than what is reported earlier.

Cone beam computed tomography and cross-sectional anatomy of the region of the fetlock in the horse (Equus caballus).

This study aimed to delineate the detailed anatomy of the metacarpophalangeal (MCP) and metatarsophalangeal (MTP) joints in healthy horses using cone beam computed tomography (CBCT). The fetlock region of 15 cadaveric forelimbs and 14 cadaveric hindlimbs from nine adult horses without orthopaedic disease underwent CBCT scanning. Additionally, arthrography CBCT scans were conducted following intra-articular injection of a radiopaque contrast medium containing blue epoxy resin dye. Subsequently, limbs were frozen and sectioned to visualize anatomical structures in sectional planes corresponding to selected CBCT images. CBCT proved suitable for detailed visualization of the bony components of the fetlock region. Furthermore, the common digital extensor tendon, superficial and deep digital flexor tendons, suspensory ligament, and straight and oblique sesamoidean ligaments were identifiable on CBCT images. However, certain ligaments, such as the collateral sesamoidean ligaments and intersesamoidean ligaments, were not clearly identified. The hyaline cartilage of the MCP and MTP joint facets was assessable on the post-contrast sequence. In cases where a radiographic or ultrasound examination cannot provide a definitive diagnosis and determine the extent of disease, CBCT can provide additional valuable data on the equine MCP and MTP joint. The images obtained in this study can serve as a reference for CBCT examination of the equine MCP and MTP joint.

Lesion Distribution in the Metacarpophalangeal and Metatarsophalangeal Region of 341 Horses Using Standing Magnetic Resonance Imaging.

Pain localised to the metacarpophalangeal (MCP) and metatarsophalangeal (MTP) region represents a frequent cause of lameness in sport horses, and standing magnetic resonance imaging (MRI) of these regions is increasingly being acquired. This multicentre retrospective study describes the ranges of abnormalities identified on standing MRI of the MCP/MTP region and compares patterns of abnormalities between forelimbs, hindlimbs and different sports disciplines. In total, 341 MRI reports were reviewed. Subchondral bone plate irregularities, condylar and proximal phalanx pathologies were frequently identified with subchondral bone defect, sclerosis and increased intensity on STIR images often described. Medial pathology was frequently identified in the forelimbs, and more lateral pathology was reported in the hindlimbs, which could potentially reflect differences in the loading patterns. Significant differences in MRI findings were found between different sports activities, with MCP/MTP bone pathology occurring more frequently in MRI reports from race and endurance horses and MCP/MTP soft tissue injuries being reported more frequently in dressage and show-jumping horses, particularly in the suspensory apparatus, including the distal sesamoidean ligaments. The findings of this study identify patterns of MCP/MTP abnormalities detected using standing MRI, with differences seen between forelimbs and hindlimbs and between different sports disciplines.

FES Control of a Finger MP Joint with a Proxy-Based Super-Twisting Algorithm

To improve motion accuracy through functional electrical stimulation (FES) of forearm muscles, feedback control laws are applied to the index finger’s metacarpophalangeal (MP) joint. This paper introduces a proxy-based super-twisting algorithm (PSTA) for precise servo control of MP joints via FES. The PSTA combines first-order sliding mode control with a second-order super-twisting algorithm, effectively preventing windup during FES saturation and ensuring robust, accurate control. An implicit Euler method minimizes numerical chattering in the digital implementation. Experiments with Arduino and volunteers confirm the algorithm’s effectiveness.

Management of paediatric fifth metacarpal neck fractures: a systematic review.

Fifth metacarpal neck fractures (FMCNFs) are common among paediatric patients. Complications include reduced metacarpophalangeal (MCP) range of motion and grip strength, which impede the hand's functional abilities. Various management options are available, but indications are not standardised. This systematic review aims to assimilate all available evidence on the management of paediatric FMCNFs to determine appropriate treatment pathways. PubMed (Medline), EMBASE, Scopus and Google Scholar were used to identify evidence pertaining to the management of these fractures. Ten studies were identified, involving 237 patients with a mean age of 14.4years (Range 9-17). Ninety percent of patients were male. Sixty-one (26%) patients, with an average fracture angulation of 27° (Range 16°-33°) and no rotational deformities, were managed with immobilisation alone. These patients returned to normal metacarpophalangeal range of motion and grip strength. Fifty-four (23%) patients, with an average fracture angulation of 42.7° (Range 33°-54°), were managed with fracture reduction and immobilisation. This technique did not yield sustained reduction of fractures with significant angulation or rotation after intervention. One hundred twenty-two (51%) patients, with an average fracture angulation of 48.3° (Range 30°-58°) and including cases of malrotation, were managed with fracture reduction and surgical fixation. These patients experienced good functional outcomes. This review suggests paediatric FMCNFs can be safely managed with immobilisation alone when there is an absence of rotational deformity and an angulation of < 30°. In the case of a higher fracture angulation or rotational deformity, fracture reduction and surgical fixation is an appropriate method of management.

Registration of finger implants in the Dutch arthroplasty registry (LROI)

Finger arthroplasty is commonly used to treat pain in the finger joints due to osteoarthritis or rheumatoid arthritis. Despite the procedure having existed for a relatively long time, it is still unknown which characteristics influence implant survival. The Dutch Arthroplasty Registry (LROI) is one of the 4 registries worldwide registering finger arthroplasties. This study aimed to investigate impact factors for implant survival regarding finger joint arthroplasty and assess registration completeness using the national healthcare claims database to compare. A total of 951 primary arthroplasties and 84 revision arthroplasties of the finger joints were registered. A higher likelihood of primary and revision surgery was found in female patients. The third and fourth proximal interphalangeal (PIP) joints were the most frequently operated in primary surgery; however, the metacarpophalangeal (MCP) joints were the most frequently revised joints. Silicone implants were used in most cases and evenly throughout all digits. Suboptimal registration completeness was shown for plastic surgeons with just 35.5%-37.4% of all surgeries registered. Although orthopedic surgeons do not perform most surgeries on the hand, they registered 76.5%-78.2% of surgeries. No statistical analyses were justified, considering the low completeness and limited follow-up. Female gender and PIP joint disease are possible risk factors for primary arthroplasty. MCP arthroplasties showed higher revision rates. However, participation rates and, therefore, data completeness were not optimal. To optimize participation, improving ease of registration should be explored. Furthermore, we urge readers who deal with joint implants to register their surgeries in the LROI database because only optimal registration completeness leads to high-quality data.

Pathomechanics of lumbrical and flexor digitorum profundus muscle tears in climbers: A cadaveric model

Lumbrical muscles originate on the flexor digitorum profundus (FDP) tendons and, during fist making, they move in the same direction when FDP muscle produces maximal proximal tendon gliding. Injuries of the bipennate lumbricals have been described when a shear force acts between the origins on adjacent tendons of the FDP, as they glide in opposite directions in asymmetric hand postures. Other structures of the deep flexors complex can be affected during this injury mechanism, due to the so-called quadriga effect, which can commonly occur during sport climbing practise. Biomechanical studies are needed to better understand the pathomechanism. A cadaveric study was designed to analyse the effects of load during the fourth lumbrical muscle injury mechanism. The amount of FDP tendon gliding and metacarpophalangeal (MCP) joint flexion of the 5th finger were calculated. Ten fresh-frozen cadaveric specimens (ten non-paired forearms and hands) were used. The specimens were placed on a custom-made loading apparatus. The FDP of the 5th finger was loaded, inducing isolated flexion of the 5th finger, until rupture. The rupture occurred in all specimens, under a load of 11 kg (SD 4.94), at 9.23 mm of proximal tendon gliding (SD 3.55) and at 21.4° (SD 28.91) of MCP joint flexion. Lumbrical muscle detachment from the 4th FDP was observed, from distal to proximal, and changes in FDP tendons at the distal forearm level too. The quadriga effect can lead to injury of the bipennate lumbrical muscles and the deep flexors complex in the hand and forearm.

Outcomes of Arthrodesis of the Metacarpophalangeal Joint of the Thumb for Sequelae of Collateral Ligament Injuries: A Series of 18 Cases with 6-Year Follow-Up.

Background: Untreated or insufficiently treated collateral ligament injuries of the thumb metacarpophalangeal (MP) joint can lead to instability or even osteoarthritis. Arthrodesis is one of the treatment options available for the treatment of the sequelae of collateral ligament injuries. The objective of our study was to evaluate the radiological, clinical and functional outcomes of MP joint arthrodesis performed for sequelae of collateral ligament injuries. Methods: We conducted a retrospective, single-centre study and reviewed the files of patients who had a thumb MP joint arthrodesis following a collateral ligament injury between 2011 and 2019. We collected patient's demographic data and the results of the radiological and clinical examinations. Results: Eighteen patients were included in the study. The average age was of 53.6 years and the time between injury to arthrodesis averaged 7 years. Four patients (22%) had nonunion. In the remaining 14 patients with solid union at an average of 72 months follow-up, the visual analogue pain score at rest was 0.14, the thumb opposition was 82%, grip strength 85%, tip pinch 92% and key pinch 79% of the contralateral side. Conclusions: The clinical and functional results of patients with a successful arthrodesis are satisfactory with restoration of good grip and pinch strength. Despite a lack of thumb MP joint flexion, stability allowed force transmission and may be preferred for manual workers. Level of Evidence: Level IV (Therapeutic).