Medial sural artery perforator free flap versus radial forearm free flap in oral cavity reconstruction and donor site morbidity.

OBJECTIVE: Radial Forearm Free flap (RFFF) is widely used in head and neck reconstruction, yet its donor site defect remains a significant drawback. The Medial Sural Artery Perforator Free Flap (MSAPFF) is considered an alternative flap to RFFF. This study aims to comprehensively analyze their characteristics, outcomes, and their impact on patient quality of life. METHODS: All patients who underwent oral cavity reconstruction using RFFF and MSAPFF between February 2017 and April 2023 were included in this study. Flap characteristics, outcomes and post-operative complications were recorded and compared. Subjective donor site morbidity, aesthetic and functional results, and quality of life were also analyzed. RESULTS: The study included 76 patients: 37 underwent reconstruction with RFFF, and 39 with MSAPFF. There was no significance difference between the RFFF and MSAPFF regarding the success rate (97.2% vs 97.4%), flap size (4.8 × 8.8 cm2 vs 5 × 9.8 cm2), hospital of stay (15.5 days vs 13.5 days) and recipient site complications (P > 0.05). However, MSAPFF showed larger flap thickness (P = 0.001), smaller arterial caliber (P = 0.008), shorter pedicle length (P = 0.001), and longer harvesting time (P < 0.001). No significant difference was observed between the pre-and postoperative ranges of wrist and ankle movements or in recipient site complications. MSAPFF showed a significant difference in donor site morbidity (P < 0.05). CONCLUSION: The MSAPFF is an excellent alternative to the RFFF for repairing oral cavity defects, with additional advantage of a well-hidden scar on the posterior calf, a larger flap thickness, accepted pedicle length and arterial caliber. However, one should consider the harvesting time and surgical skills required in comparison to the RFFF. CLINICAL RELEVANCE: The study highlights the importance of the MSAPFF as an alternative option for RFFF with less donor site morbidity and high success rate in oral cavity reconstruction and improved patient Quality of life after ablative surgery.

Aerobic Exercise Training Combined with Local Strength Exercise Restores Muscle Blood Flow and Maximal Aerobic Capacity in Long-Term Hodgkin Lymphoma Survivors.

BACKGROUND: It is unclear whether muscle blood flow (MBF) is altered in long-term Hodgkin Lymphoma (HL) survivors. We test the hypothesis that: 1) MBF response during mental stress (MS) is impaired in long-term HL survivors; 2) Aerobic exercise training combined with local strength exercise (ET) restores MBF responses during MS in these survivors. METHODS: Eighteen 5-year HL survivors and 10 aged-paired healthy subjects (HC) were studied. Twenty HL survivors were randomly divided into two groups: Exercise-trained (HLT, n=10) and untrained (HLUT, n=10). Maximal aerobic capacity was evaluated by a cardiopulmonary exercise test and forearm blood flow (FBF) by venous occlusion plethysmography. MS was elicited by Stroop Color Word Test. ET was conducted for four months, three/week for 60 minutes each session. The aerobic exercise intensity corresponded to anaerobic threshold up to 10% below the respiratory compensation point. The strength exercises consisted of 2-3 sets of chest press, pulley and squat exercises, 12-15 repetitions each exercise at 30-50% of the maximal voluntary contraction. RESULTS: Baseline was similar in HL survivors and HC, except peak oxygen consumption (peak VO2, p=0.013) and FBF (p=0.006) that were lower in the HL survivors. FBF responses during MS were lower in HL survivors (p<0.001). ET increased peak VO2 (11.59±3.07%, p=0.002), and FBF at rest (33.74±5.13%, p<0.001) and during MS (24±5.31%, p=0.001). Further analysis showed correlation between the changes in peak VO2 and the changes in FBF during MS (r=0.711, p=0.001). CONCLUSION: Long-term HL survivors have impaired MBF responses during MS. ET restores MBF responses during MS.

Case report of substantial reconstruction of second ray segment by osteo-tendo-cutaneous pedicled radial forearm flap.

Introduction and importance: The hand is one of the most vital organ that the surgeon aims to preserve its function and natural appearance. Gunshot injuries are common, especially in a war zone, and unfortunately, they create complex wounds that are hard to reconstruct and infection is very common. In this article, we report rebuilding segment of index finger with a pedicled osteo-tendo-cutaneous radial forearm flap. Case presentation: A 50-year-old man-African with no past medical comorbidities, sustained trauma to his left index finger by high-velocity injury that led to composite tissue loss including metacarpal and proximal phalanx. After applying the initial irrigation and dressing to the wound, his hand was supported by a volar cast then he was referred to the hospital. The hand was examined at the operation room and the index finger was found to be hanged with a medial skin pedicle with necrotic and exposed bone and tendon. He underwent a session of debridement followed by reconstruction using a pedicled osteo-cutaneous radial forearm flap accompanied with metacarpophalangeal joint arthrodesis. Clinical discussion: A significant number of war-related hand injuries resulted in amputations because there were not enough facilities or doctors. While they are alternatives to free flap, abdominal and regional flaps won't yield the same outcomes. The second ray of the hand is reshaped using a radial flap, producing an acceptable result. Conclusion: The Radial forearm flap was used to reconstruct segment of index finger and fulfill our requirements, which include bone, tendon, and skin cover. Additionally, this is a simple and single stage procedure and micro-surgical equipment is not necessary.

Optimizing Flap Measurements for Tongue Reconstruction: Harnessing the Power of the Pythagorean Formula.

Head and neck reconstruction, particularly tongue reconstruction, remains a formidable challenge. However, crafting a three-dimensional structure from a basic flap necessitates precise dimensions to avoid excess or insufficiency. At the same time, the tongue also has to be accommodated inside the oral cavity to prevent protrusion or repeated injuries due to tooth bites. This study aims to showcase the practicality of employing Pythagoras's formula in both preoperative and intraoperative settings to the required flap dimensions for partial and hemiglossectomy tongue defects. Between 2020 and 2022, we have undertaken 53 tongue reconstructions to address defects resulting from partial or hemiglossectomies. Among these cases, 51 were managed with free radial artery flaps, while in two we utilized anterolateral thigh flaps for reconstruction. Our study excluded cases involving minor tongue defects amenable to primary closure. By treating the length of the tongue defect as the hypotenuse, Pythagoras's formula is applied to calculate the optimal length and width of a free microvascular flap. The tongue reconstruction is performed, and microvascular anastomosis is carried out in the neck. An addition was made for associated buccal mucosa defects, if any. All flaps survived without any complications like bleeding, wound dehiscence, and partial or complete flap necrosis. Tongue movement was adequate, with good swallowing and good speech. The application of Pythagoras's formula provides a dependable method for determining flap size pre- and intraoperatively in cases of partial or hemiglossectomy tongue defects, leading to favorable functional and aesthetic results.

Single Bone Intramedullary Fixation of the Radius in Pediatric Both Bone Forearm Fractures Using Straight Stainless Steel Kirschner Wire: A Cross-sectional Study on Radiological and Clinical Feature.

Objectives: We aimed to report radiological and clinical features of single bone intramedullary fixation of the radius in pediatric both bone forearm fractures using straight stainless steel Kirschner (K) wire. Methods: Fifty-eight children (42 boys and 16 girls) referred to our hospital with both bone diaphyseal forearm fractures were operated on by using the single bone rigid K-wire intramedullary fixation and mini-open technique. The mean follow-up time was 8.9 months (6-12). Results: The mean age of the patients was 7.4 years (4-12). More than 2/3 of the fractures were in the right hand. Around 63% of the fractures were in the middle third, 28% in the distal third, and 9% in the proximal third. Moreover, 12% were open type I Gustilo-Anderson fractures. The mean time from injury to surgery was two days (1-4), and the mean length of hospital stay was 2.8 days (2-5). The mean duration of surgery was 24.7 minutes (18-38), and the mean follow-up time was 8.9 months (6-12). All fractures united within 4-16 weeks (mean: 7.62). The cast and implant were removed simultaneously as the radiographic fracture union. There was no serious complication. Superficial infection of the pin track and loosening of the pin occurred in three cases (5%), all controlled by antibiotics and timely removal of the pins. Mild restriction of elbow extension (less than 20 degrees) was observed in three cases, which returned to normal at the last follow-up. Limitation of dorsiflexion of the wrist by more than 20° occurred in two patients (35° and 45°), which reverted to 25° and 25°, respectively, at the last follow-up. Conclusion: In both bone forearm fractures in children, open reduction and internal fixation of only the radius with a stainless steel straight Kirschner wire could be a promising method with good results. This retrograde technique of intramedullary fixation is a simple and cost-effective method with minimal complications and acceptable outcomes in children aged 4-12 years.

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).

"Preventing nail migration by stack nailing in forearm fractures" - A technical note.

Diaphyseal forearm fractures are typically treated with open reduction and plate fixation, which has been proven to be the most effective method in numerous trials. However, the risk of periosteal stripping, haemorrhage evacuation, nonunion, and infection is always present and may cause a delayed union and other surgical consequences. Although intramedullary nails have been mentioned in the literature for forearm bone fractures, issues regarding their common complication of nail migration, especially of the ulnar fracture, before the fracture has been consolidated is an issue, and has not been addressed. We describe a case of IM nail migration of Ulna who presented to us, during the follow up, before the fracture had consolidated. The procedure described is short and consistent with the outstanding cosmetic and functional results.

Diaphyseal forearm fracture management in adolescent patients from 2011 to 2020: A multicenter study of surgery and regional anesthesia trends.

BACKGROUND: Diaphyseal forearm fractures are common traumatic injuries among children. There has been much debate on the use of intramedullary nailing (IMN) or plate fixation in the adolescent population (10-16 years of age). Furthermore, as ultrasound technology has advanced, the safety and efficacy of ultrasound-guided axillary brachial plexus block for children has dramatically improved. Therefore, anesthesia options for adolescent patients have increased in recent years. This study aimed to investigate recent surgical and regional anesthesia trends of diaphyseal forearm fractures in patients 10 to 16 years of age in Japan through a multicenter epidemiological survey from 2011 to 2020. METHODS: This retrospective, multicenter study included 226 pediatric patients with diaphyseal forearm fracture aged 10-16 years treated from January 2011 to December 2020. We divided the patients into four groups according to the period in which they were treated: early (2011-2013), middle (2014-2016), late (2017-2019), and COVID-19 (2020). Information from medical records was used to investigate the number of surgeries, types of anesthesia administered, and internal fixation methods used for diaphyseal forearm fracture in adolescent patients during each period. RESULTS: The number of surgeries was generally constant in each period but decreased during the COVID-19 period. In the early, middle, late, and COVID-19 periods, the percentages of surgeries performed under regional anesthesia were 67.7, 85.5, 87.0, and 100% respectively (p = 0.003). During the same periods, the percentages of patients receiving IMN were 41.5, 49.3, 58.0, and 66.7%, respectively (p = 0.033). CONCLUSION: The use of IMN and regional anesthesia to treat diaphyseal forearm fracture in patients 10 to 16 years of age steadily increased during the study period from 2011 to 2020. These results indicate that regional anesthesia is safe, effective, and well-tolerated by adolescent patients. The treatment strategy for diaphyseal forearm fractures in adolescents using regional anesthesia in combination with IMN worked well and was effective during COVID-19. Our evidence suggests this trend will continue. We anticipate that our findings can be extrapolated for upper extremity fractures in adolescent patients beyond the Tokai region of Japan where the study was based.

Early total reconstruction for a Gustilo type IIIB open forearm fracture associated with avulsion injury of multiple extensor tendons: A case report.

Gustilo type IIIB open forearm fractures associated with avulsion injuries of multiple extensor tendons are difficult to reconstruct. Not only are bones, nerves, blood vessels, and soft tissues injured, but also tendons directly related to hand function. A 74-year-old man sustained an injury to his dominant right hand after being hit by a heavy pulley. The patient was diagnosed with a Gustilo type IIIB open forearm fracture, and multiple extensor tendons were avulsed from the musculotendinous junction. On the day of injury, the radius was fixed using a volar locking plate, and the ulnar head was fixed to the radius. On the fourth day, the avulsed extensor tendons were reconstructed using tendon transfer, and the exposed tendons and soft tissue defects were covered using a free anterolateral thigh flap on the seventh day. Three years after the injury, the patient had no difficulty in performing activities of daily living. Single-stage reconstruction allows for early rehabilitation. We believe that the more complex and severe the injury is, the more we should aim to repair the injured tissue as early as possible, that is, early total reconstruction.

The osteocutaneous radial forearm free flap: A pictorial essay.

The osteocutaneous radial forearm free flap (OCRFFF) is a versatile flap with the ability to reconstruct complex defects. We detail the techniques necessary to harvest an OCRFFF, including an outline on making 90-degree osteotomies to maximize bone harvest. In this pictorial essay, we provide illustrations of the anatomy and surgical techniques necessary for OCRFFF harvest. Detailed discussion is provided on how to protect the perforators to the bone and the approach to making osteotomies in a 90-degree fashion. The approach for prophylactic plating of the radius to prevent radius fractures is outlined. A case presentation on the real-life utilization of this flap is included. The OCRFFF is an excellent head and neck reconstructive option. While there are limitations to its use for patients requiring dental rehabilitation or long/anterior mandibular defects, for the right patient and indication it has shown great success in reconstructive efforts.

Assessment of Variability in Free Flap Color Match to Facial Skin by Donor Site and Race.

OBJECTIVES: To use portable colorimetry to quantify color differences between facial skin and potential three head and neck microvascular free tissue transfer (MFTT) donor sites-radial forearm (RF), anterolateral thigh (ALT), and fibula (FF)-and compare these differences by pigmentation of the donor site skin and self-identified race. METHODS: In this cross-sectional cohort study, healthy volunteers consented to handheld colorimeter measurements at the three potential MFTT donor sites (RF, ALT, FF) to quantify color match to the facial skin using the CIE color space (DeltaE). The comparison of ipsilateral to contralateral cheek served as control for measurements. Cross-sectional measurements in healthy volunteers were then compared to measurements obtained in postoperative head and neck MFTT patients. RESULTS: DeltaE measurements were obtained for 128 healthy controls and 24 postoperative patients (N = 152). With increasing lightness (decreased pigmentation) of the skin at the donor site, the color match significantly worsened (higher DeltaE) across all potential MFTT donor sites (all p < 0.05). DeltaE from healthy controls closely approximated postoperative color match measurements in patients who underwent cervicofacial MFTT (DeltaE RF: 5.3 vs. 6.0, p = 0.432; DeltaE ALT: 6.2 vs. 6.4, p = 0.822; DeltaE FF: 6.0 vs. 6.4, p = 0.806). CONCLUSION: Patients with decreased skin pigmentation who are undergoing head and neck MFTT may experience worse color discrepancy between cervicofacial skin and the transferred skin paddle than those with more pigmented skin. Portable colorimetry may identify patients who could benefit from interventions such as dermis-resected free tissue reconstruction with skin grafting to improve postoperative appearance. LEVEL OF EVIDENCE: 3 Laryngoscope, 2024.

Intramedullary versus plate fixation of both bone forearm fractures in skeletally immature patients: a systematic review and meta-analysis.

BACKGROUND: Both bone forearm fractures (BBFFs) are a common injury amongst the pediatric population. The main indications of surgical fixation are open, irreducible, or unstable fractures. The two most commonly used surgical techniques are closed or open reduction with intramedullary fixation (IMF) and open reduction with plate fixation (PF). The aim of this systematic review and meta-analysis was to determine which fixation method is superior for BBFFs. METHODS: PubMed, Scopus, Web of Science, and CENTRAL were searched to identify studies comparing IMF and PF. We extracted data on union rates, complications, early hardware removal rates, reoperation rates, and radiographic, clinical, and perioperative outcomes. RESULTS: Sixteen studies were included in the analysis, with a total of 922 patients (539 IMF and 383 PF). Similar union rates were achieved by both fixation technique. IMF was associated with a higher incidence of symptomatic hardware, and early hardware removal. Better restoration of the radial bow was observed with the PF group, especially in older children and adolescents. The rate of excellent function was comparable between groups, whereas better cosmesis was reported with the IMF group. Despite shorter fluoroscopy time and immobilization time, PF demonstrated longer tourniquet time, operating time, and hospital stay compared to IMF. CONCLUSIONS: We found no significant difference between IMF and PF in terms of union rates and functional outcomes taking in consideration the merits and demerits of each technique. High-quality randomized controlled trials are, therefore, necessary to determine the superiority of one fixation technique over the other. LEVEL OF EVIDENCE: III.

Innovative Approaches to 3D Printing of PA12 Forearm Orthoses: A Comprehensive Analysis of Mechanical Properties and Production Efficiency.

This research paper aims to explore the mechanical characteristics of polyamide PA12 (PA12) as a 3D material printed utilizing Selective Laser Sintering (SLS) and HP MultiJet Fusion (HP MJF) technologies in order to design and manufacture forearm orthoses. The study assessed the flowability of the materials used and compared the mechanical performance of PA12 with each other using tensile, flexure, and impact tests in five different fabrication orientations: X, Y, Z, tilted 45° XZ, and tilted 45° YZ. The results of the study provide, firstly-the data for testing the quality of the applied polyamide powder blend and, secondly-the data for the design of the orthosis geometry from the aspect of its strength parameters and the safety of construction. The mechanical parameters of SLS specimens had less variation than MJF specimens in a given orientation. The difference in tensile strength between the 3D printing technologies tested was 1.8%, and flexural strength was 4.7%. A process analysis of the forearm orthoses revealed that the HP MJF 5200 system had a higher weekly production capacity than the EOS P396 in a production variance based on obtaining maximum strength parameters and a variance based on maximizing economic efficiency. The results suggest that medical device manufacturers can use additive manufacturing technologies to produce prototypes and small-batch parts for medical applications. This paper pioneers using 3D printing technology with Powder Bed Fusion (PBF) methods in designing and manufacturing forearm orthoses as a low- to medium-volume product. The applied solution addresses the problem of medical device manufacturers with regard to the analysis of production costs and mechanical properties when using 3D printing for certified medical devices.

A PRISMA-IPD systematic review and meta-analysis: does age and follow-up improve active range of motion of the wrist and forearm following pediatric upper extremity cerebral palsy surgery?

Purpose: Surgical treatments such as tendon transfers and muscle lengthening play a significant role in cerebral palsy management,but timing of upper extremity cerebral palsy surgery remains controversial. This study systematically reviews the current literature and investigates the correlation between age at surgery and follow-up time with surgical outcomes in pediatric upper extremity cerebral palsy patients. Methods: A comprehensive search of PubMed, Cochrane, Web of Science, and CINAHL databases was performed from inception to July 2020 and articles were screened using PRISMA guidelines to include full-text, English papers. Data analysis was performed using itemized data points for age at surgery, follow-up length, and surgery outcomes, reported as changes in active forearm and wrist motion. A 3D linear model was performed, to analyze the relationship between age, follow-up length, and surgery outcomes. Results: A total of 3,855 papers were identified using the search terms and a total of 8 studies with itemized patient data (n=126) were included in the study. The studies overall possessed moderate bias according to the ROBINS-I scale. Regression analysis showed that age is a significant predictor of change (|t| > 2) in active forearm supination (Estimate = -2.3465, Std. Error = 1.0938, t-value= -2.145) and wrist flexion (Estimate = -2.8474, Std. Error = 1.0771, t-value = -2.643) post-intervention, with older individuals showing lesser improvements. The duration of follow-up is a significant predictor of improvement in forearm supination (Estimate = 0.3664, Std. Error = 0.1797, t-value = 2.039) and wrist extension (Estimate = 0.7747, Std. Error = 0.2750, t-value = 2.817). In contrast, forearm pronation (Estimate = -0.23756, Std. Error = 0.09648, t-value = -2.462) and wrist flexion (Estimate = -0.4243, Std. Error=0.1859, t-value = -2.282) have a significant negative association with follow-up time. Conclusion: These results suggest that there is significant correlation between the age and follow up after surgery with range of motion gains. Most notably, increased age at surgery had a significant negative correlation with select active range of motion postoperative outcomes. Future research should focus on identifying other factors that could affect results of surgical treatment in upper extremity.

Associations between ultra-distal forearm bone mineral density and incident fracture in women.

Bone mineral density measured at the ultra-distal forearm site was associated with any fracture, as well as distal radius fracture in women from a longitudinal cohort study. PURPOSE: Femoral neck (BMDhip) and lumbar spine (BMDspine) bone mineral density (BMD) are routinely used to assess fracture risk. More data are needed to understand how ultra-distal forearm BMD (BMDUDforearm) may assist fracture prediction. METHODS: Using a Lunar DPX-L, Geelong Osteoporosis Study women (n = 1026), aged 40-90 years, had BMD measured. Incident low-trauma fractures were radiologically verified. Using Cox proportional hazard models, hazard ratios (HR) were calculated for BMDUDforearm as a continuous variable (expressed as a one-unit decrease in T-score) and a categorical variable (normal/osteopenia/osteoporosis). Areas under receiver operating characteristics (AUROC) curves were calculated. Analyses were conducted for any fracture and distal radius fractures. RESULTS: During 14,270 person-years of follow-up, there were 318 fractures (85 distal radius). In adjusted models, continuous BMDUDforearm was associated with any (HR 1.26;95%CI 1.15-1.39) and distal radius fractures (HR 1.59;95%CI 1.38-1.83). AUROCs for continuous BMDUDforearm, 33% forearm(BMD33%forearm), BMDhip, BMDspine, and FRAX without BMD were similar for any fracture (p > 0.05). For distal radius fracture, the AUROC for BMDUDforearm was higher than other sites and FRAX (p < 0.05). In adjusted models, those with osteoporosis had a higher likelihood of any fracture (HR 2.12; 95%CI 1.50-2.98). For distal radius fractures, both osteopenia and osteoporosis had a higher risk (HR 4.31; 95%CI 2.59-7.15 and 4.81; 95%CI 2.70-8.58). AUROCs for any fracture were similar for categorical BMD at all sites but lower for FRAX (p < 0.05). For distal radius fractures, the AUROC for BMDUDforearm, was higher than other sites and FRAX (p < 0.05). CONCLUSION: Ultra-distal forearm BMD may aid risk assessments for any distal radius fractures.

A Useful Technique for Templating the Reverse Radial Forearm Flap (RFF) for Thumb Degloving Injuries.

Degloving injuries of the thumb pose a significant challenge as replantation is usually unsuccessful. A 60-year-old man was transferred to "Queen Victoria Hospital NHS Trust" four hours after having his left thumb completely avulsed at metacarpophalangeal level. The anastomosis repeatedly failed during urgent replantation and a distally based pedicled RFF was utilized. To achieve accurate flap design, we used the amputated part as a template for the missing tissue. After a longitudinal cut exposing the inner surface, the thumb was placed flat on top of a clean gauze package which was used as a paper template for the skin paddle; the flap was subsequently sutured without tension. Since the circumferential soft tissue envelope is three-dimensional, accurate designing of the flap on the forearm is vital. We propose a useful technique using the amputated part to enable a precise estimation of the tissue requirements to reduce potential complications related to flap inset.

Les lésions de dégantage du pouce posent un défi significatif dans la mesure où la réimplantation échoue habituellement. Un homme âgé de 60 ans a été transféré à « Queen Victoria Hospital NHS Trust ¼ quatre heures après l'arrachement complet de son pouce au niveau métacarpophalangien. L'anastomose a échoué de manière répétée au cours de la réimplantation en urgence et un RFF pédiculé à base distale a été utilisé. Pour obtenir une forme exacte du lambeau, nous avons utilisé la partie amputée comme modèle pour le tissu manquant. Après une incision longitudinale exposant la surface interne, le pouce a été mis à plat sur un paquet de compresses propres qui a servi de modèle papier pour la palette de peau; le lambeau a ensuite été suturé sans tension. Considérant que l'enveloppe de tissu souple circonférentielle est tridimensionnelle, une détermination précise du lambeau sur l'avant-bras est vitale. Nous proposons une technique utile consistant à utiliser la partie amputée pour avoir une estimation précise des besoins en tissu afin de réduire les complications potentielles liées à l'insertion du lambeau.

Improved Reliability of Electromyography-Based Neuromuscular Monitoring During Laparoscopic Surgery Achieved by the Modified Attachment Method for Nihon-Kohden NM-345Y™ Stimulating Electrodes: A Case Report.

Neuromuscular monitoring is crucial during the administration of neuromuscular blocking agents owing to individual variations in their effects. In electromyography (EMG)-based neuromuscular monitoring using the EMG electrodes (NM-345Y™, Nihon-Kohden Corporation, Tokyo, Japan) following the manufacturer-recommended attachment method, the accuracy of neuromuscular monitoring may be reduced when forearm limb position is changed. We previously devised a novel attachment method for NM-345Y™ stimulating electrodes in adult volunteers to maintain stable monitoring accuracy despite changes in forearm position. Its effectiveness in clinical practice was evaluated by conducting a descriptive study on a 52-year-old woman undergoing laparoscopic uterine surgery. NM-345Y™ electrodes were attached to each forearm following the manufacturer's recommendations (Pattern N) and our novel method (Pattern C). In Pattern C, NM-345Y™ was attached without ultrasound guidance so that the ulnar nerve crossed the line connecting the centers of the anode and cathode of the stimulating electrode. Pattern C exhibited consistent EMG-based monitoring accuracy even with changes in forearm position despite a smaller stimulus current value at calibration. Additionally, Pattern C displayed reliable recovery of the train-of-four (TOF) response after sugammadex administration in the original forearm position, with no observed adverse events. In contrast, Pattern N showed unstable monitoring accuracy after forearm position changes, highlighting the danger of imprecise EMG-based neuromuscular monitoring during the administration of neuromuscular blocking agents. The study's strength lies in identifying Pattern C, where the ulnar nerve crosses the line connecting the anode and cathode, significantly enhancing monitoring accuracy. This novel attachment method holds promise to improve EMG-based neuromuscular monitoring precision in surgery involving forearm limb position changes, although further research is required to assess its utility comprehensively.

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.

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).

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.