Journal of Hand Surgery-American Volume最新文献

{"title":"Tendon Inversion Improves Tendon-to-Bone Healing in a Rat Bicep Tenodesis Model.","authors":"Ting Cong, Thomas M Li, Dustin C Buller, Varun Arvind, Philip Nasser, Damien M Laudier, Harrison R Ferlauto, Arielle J Hall, Deborah M Li, Efstathios Konstantinou, Alice H Huang, Paul J Cagle, Leesa M Galatz, Michael R Hausman","doi":"10.1016/j.jhsa.2024.12.012","DOIUrl":"https://doi.org/10.1016/j.jhsa.2024.12.012","url":null,"abstract":"<p><strong>Purpose: </strong>Tendon-to-bone repair remains a surgical challenge. Although bone tunnel fixation is a common surgical technique whereby soft tissue is expected to heal against a bone tunnel interface, contemporary methods have yet to recapitulate biomechanical similarity to the native enthesis. In this study, we aimed to understand how inside-out longitudinal tendon inversion affects bone tunnel healing with the hypothesis that inversion removes the gliding epitenon surface to facilitate interface healing.</p><p><strong>Methods: </strong>Forty male Sprague-Dawley rats underwent either native tendon tenodesis (control group) or tendon inversion tenodesis (experimental group). Interface tissue was harvested 8 weeks after surgery. Biomechanical testing was performed to assess tensile strength and modes of failure. Histology was performed to assess tissue architecture, and immunohistochemistry confirmed the disruption of epitendinous lubricin from interface tissues.</p><p><strong>Results: </strong>Maximum tensile strength increased after tendon inversion compared with control surgery. The extracellular matrix protein lubricin was reduced with tendon inversion, and specimens with tendon inversion had greater healing scores and collagen fibril alignment at the healing interface.</p><p><strong>Conclusions: </strong>Tendon inversion has the potential to improve bone tunnel healing in rats.</p><p><strong>Clinical relevance: </strong>Our findings suggest that longitudinal tendon inversion, or inverse tubularization, in a rat biceps model improves tendon-to-bone healing in part because of disruption of the epitendinous surface at the bone healing interface. This work provides molecular insight into future improvements for tendon-to-bone repair surgical techniques.</p>","PeriodicalId":54815,"journal":{"name":"Journal of Hand Surgery-American Volume","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143025381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Incidence and Presentation of Periprosthetic Joint Infection After Primary Metacarpophalangeal and Proximal Interphalangeal Arthroplasty.","authors":"Adam T Schluttenhofer, Matthew M Rode, Marco Rizzo, Peter M Murray","doi":"10.1016/j.jhsa.2024.12.008","DOIUrl":"https://doi.org/10.1016/j.jhsa.2024.12.008","url":null,"abstract":"<p><strong>Purpose: </strong>Periprosthetic joint infection (PJI) is a devastating complication that has been extensively investigated in large joint arthroplasty. However, this has been inconsistently reported after metacarpophalangeal (MCP) and proximal interphalangeal (PIP) arthroplasty. The objective of the study was to report the presentation and treatment of patients with PJI after MCP or PIP joint arthroplasty.</p><p><strong>Methods: </strong>We performed a retrospective review of 1418 primary MCP or PIP arthroplasties in 642 patients with a minimum of 180 days of follow-up (mean 9.0 years) at a single institution from 1991 to 2020. We also analyzed the association of patient (body mass index, smoking, diabetes, and immunocompromised status) and surgical (digit, implant, operative time, and reoperation) factors with infection.</p><p><strong>Results: </strong>There were six joints, all in separate patients, that developed PJI (0.4%). The median time to PJI was 91.5 days. Of the six patients with PJI, five had no systemic symptoms and a normal leukocyte count. The most common cultured organism was Staphylococcus aureus. PJI was most commonly treated with hardware removal and antibiotics.</p><p><strong>Conclusions: </strong>PJI is uncommon after MCP or PIP arthroplasties. It commonly presents without systemic symptoms or leukocyte count and is most frequently caused by Staphylococcus aureus. More studies are needed to identify the optimal diagnostic criteria, treatment, and preventive strategies of PJI of the MCP and PIP joints.</p><p><strong>Type of study/level of evidence: </strong>Therapeutic IV.</p>","PeriodicalId":54815,"journal":{"name":"Journal of Hand Surgery-American Volume","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143025379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Displaced Fleck Sign: Description of a Radiographic Finding Consistent with Grade III Thumb Ulnar Collateral Ligament Tears with Stener Lesions.","authors":"Joshua R Daryoush, Hernan Roca, Brittany N Garcia, Nikolas H Kazmers","doi":"10.1016/j.jhsa.2024.12.003","DOIUrl":"https://doi.org/10.1016/j.jhsa.2024.12.003","url":null,"abstract":"<p><strong>Purpose: </strong>Controversy exists regarding the optimal imaging modality (magnetic resonance imaging, ultrasound, stress radiographs) for identification of patients with grossly unstable thumb metacarpophalangeal (MCP) ulnar collateral ligament (UCL) injuries or Stener lesions. We characterize a radiographic sign for this purpose. The \"displaced fleck sign\" is a small avulsion fracture from the ulnar proximal phalanx base that is displaced proximal to the MCP joint line.</p><p><strong>Methods: </strong>Patients with thumb UCL injuries evaluated by hand surgeons were identified at a single, tertiary institution. Patients who were skeletally immature, had chronic injuries (>3 months old), and those with MCP arthritis were excluded. Two attending hand surgeons independently reviewed radiographs to identify the displaced fleck sign. Presence/absence of a Stener lesion was extracted from operative notes.</p><p><strong>Results: </strong>Of 228 patients, 17 (7.5%) had a positive displaced fleck sign. Excellent interobserver reliability was observed (κ = 0.94). All 17 (100%) demonstrated gross instability with no end point in clinic, and all underwent surgical repair. Grade III ruptures were noted for all. Specifically, 14 (94.1%) had a Stener lesion, and one patient (7%) had a bony avulsion from the metacarpal. The displaced fleck sign had a positive predictive value of 100% for Grade III rupture and 94.1% for a Stener lesion.</p><p><strong>Conclusions: </strong>Presence of a displaced fleck sign has implications for offering surgery to patients with thumb UCL injuries because of a high likelihood of a Stener lesion. When present, surgeons may consider proceeding with surgical repair without additional imaging and associated follow-up visits.</p><p><strong>Type of study/level of evidence: </strong>Prognosis IV.</p>","PeriodicalId":54815,"journal":{"name":"Journal of Hand Surgery-American Volume","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143016632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Time to Recovery of Radial Nerve Palsy After Surgically Treated Humeral Shaft Fractures.","authors":"Carlos Gomez, Alfonso Perez, Juan Manuel Breyer, Pamela Vergara","doi":"10.1016/j.jhsa.2024.11.024","DOIUrl":"https://doi.org/10.1016/j.jhsa.2024.11.024","url":null,"abstract":"<p><strong>Purpose: </strong>The purpose of this study was to report a timeframe for neurologic recovery of complete radial nerve palsies in patients with humeral shaft fractures treated with internal fixation.</p><p><strong>Methods: </strong>We retrospectively analyzed the data of patients who underwent surgical treatment of a humeral shaft fracture between 2016 and 2021 at a level I trauma center. Patients with complete sensory and motor radial nerve palsy were identified. The time elapsed until detection of the first clinical signs of neurologic recovery, and then until full function (M5 according British Medical Research Council scale) was measured.</p><p><strong>Results: </strong>Of 32 radial nerve palsies in 471 surgically treated humeral shaft fractures (6.8%), 17 were recorded at the time of injury and 15 were noted after surgery. Median patient age was 31.5 years (range, 19-58 years). Thirty patients recovered full motor function at a median time of 36 weeks (range, 6-83 weeks). Kaplan-Meier analyses showed that 90.6% of patients presented the first signs of nerve recovery in the initial 6 months of observation. At 12 and 18 months of follow-up, 84.3% and 94% of patients, respectively, had recovered full function of the hand and wrist.</p><p><strong>Conclusions: </strong>Surgically treated humeral shaft fractures associated with radial nerve palsies are expected to show signs of neurologic recovery during the first 6 months and should recover completely after 12 months of follow-up in almost all cases.</p><p><strong>Level of evidence: </strong>Prognosis II.</p>","PeriodicalId":54815,"journal":{"name":"Journal of Hand Surgery-American Volume","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143016641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Management of Upper-Extremity Xylazine-Associated Wounds.","authors":"Parker Johnsen, Effie Morway, Aaron Jackson, Sara Hope Buchner, Pietro Gentile, Asif M Ilyas, Katharine Criner Woozley","doi":"10.1016/j.jhsa.2024.11.017","DOIUrl":"https://doi.org/10.1016/j.jhsa.2024.11.017","url":null,"abstract":"<p><strong>Purpose: </strong>Xylazine has been associated with necrotic soft tissue wounds that have placed a challenging burden on patients who inject drugs in the Philadelphia region's health care system over the last few years. An analysis of our initial experience is being presented to guide future treatment and directions for future research.</p><p><strong>Methods: </strong>A retrospective review of 55 patients with patient-reported xylazine use and associated upper-extremity wounds at a single institution was performed. Patient demographics, treatments, and outcomes are presented.</p><p><strong>Results: </strong>A large percentage of patients with xylazine-associated wounds were homeless (40%), had concomitant psychiatric diagnoses (26%), and had a history of tobacco use (84%). Comorbidities included 5% who were human immunodeficiency virus-positive and 67% who were hepatitis C virus-positive. The median number of hospital admissions per patient for xylazine-associated wounds was 3, with an average of 5.9 (range: 1-44 admissions). The median length of stay per hospital admission was 3 days, with an average of 5.3 days (range: 1-75). Among all included patients, 33 of 55 patients (60%) were treated nonoperatively with local wound care. Of the 22 patients who underwent surgery, there was a surgical complication rate of 59%, primarily related to continued wound issues, infections, and graft failures. The overall rate of patients who left the hospital against medical advice (AMA) was 49%. However, the mortality rate was 0%. Most surgical patients left AMA during their postoperative period hospital stay (64%) and demonstrated continued drug use per review of their hospital records (68%).</p><p><strong>Conclusions: </strong>Patients presenting with xylazine-associated wounds have a high incidence of homelessness, psychiatric diagnoses, tobacco smoking, hepatitis C virus, and a predilection both toward leaving the hospital AMA and repeated drug use. These variables create inherent challenges to reconstructive surgery, yielding a subsequently high complication rate identified in most surgically managed patients.</p><p><strong>Type of study/level of evidence: </strong>Therapeutic study IV.</p>","PeriodicalId":54815,"journal":{"name":"Journal of Hand Surgery-American Volume","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143016640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Looped Penrose Drainages of Acute Hand Infections in Vulnerable Populations.","authors":"Jane N Ewing, Yoshiko Toyoda, Mehdi S Lemdani, John R Vaile, Elizabeth Malphrus, Zachary Gala, Chris Amro, Robyn B Broach, Benjamin Chang","doi":"10.1016/j.jhsa.2024.11.015","DOIUrl":"https://doi.org/10.1016/j.jhsa.2024.11.015","url":null,"abstract":"<p><strong>Purpose: </strong>Acute hand infections (AHIs) remain a challenge for hand surgeons and represent a condition for which clinical outcomes are considerably affected by social barriers. We previously described the looped Penrose drainage technique, where a drain is sutured to itself in a loop and the outflow tract of egress is maintained, thus obviating the need for large incisions, wound closure, or repeat packing, thereby reducing the follow-up burden. In the face of escalating numbers of socioeconomically vulnerable patients, especially in urban settings, we aimed to characterize the clinical features and outcomes of this technique in an urban population of patients with AHI.</p><p><strong>Methods: </strong>A review of all surgical irrigations of AHI by a single, fellowship-trained hand surgeon at an urban hospital from 2013 through 2021 was performed. Patient demographics, procedure details, and postprocedure outcomes were analyzed.</p><p><strong>Results: </strong>Fifty-three patients (average age, 48.6 years) with AHI underwent surgical irrigations with the looped Penrose drainage technique. The majority of patients were Black (50.9%). Approximately 81.1% of the patients received public insurance, 22.6% were unemployed, 35.9% had annual incomes <$40,000, and 17% experienced homelessness. Overall, 34% were lost to follow-up with the Penrose still intact, including 78% of those who were homeless. Most of the cases occurred on the hand, with involvement of the deep spaces (24.5%), tenosynovitis (39.3%), and bone (1.9%). Recurrent infection (1.9%) and abscess formation (5.7%) led to one reoperation (1.9%). There were no amputations or readmissions, and all postoperative emergency department visits (7.1%) were discharged.</p><p><strong>Conclusions: </strong>The looped Penrose technique is a simple and less invasive alternative to traditional incision and drainage with packing and serves as an effective single-episode intervention strategy for AHIs, particularly in patients with complex social challenges because of the ease of wound management and low rates of readmission and reoperation.</p><p><strong>Type of study/level of evidence: </strong>Therapeutic IV.</p>","PeriodicalId":54815,"journal":{"name":"Journal of Hand Surgery-American Volume","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143016623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adolescent Coronal Shear Fractures of the Distal Humerus: Surgical Approach and Outcomes.","authors":"David Wright, Zachary Meyer, Charles A Goldfarb, Lindley B Wall","doi":"10.1016/j.jhsa.2024.11.016","DOIUrl":"https://doi.org/10.1016/j.jhsa.2024.11.016","url":null,"abstract":"<p><strong>Purpose: </strong>Isolated coronal shear fractures of the distal humerus in adolescents are rare injuries with unique surgical challenges. Respect for the posterior blood supply, open physes, and need for direct visualization to achieve anatomic reduction are critical considerations in surgical fixation. This study presents a case series and a surgical approach used in treating these patients.</p><p><strong>Methods: </strong>A retrospective review of patients aged 10-19 presenting to a single quaternary-care academic center from 2016 to 2023 with isolated capitellar and trochlear shear fractures was performed. Demographic data, injury mechanism, fracture classification, and surgical approach were recorded. Outcomes included elbow range of motion at the final follow-up, visual analogue scale pain scores, pediatric Patient-Reported Outcome Measurement Information System (PROMIS) scales, radiographic and clinical union, return to sport, and postoperative complications.</p><p><strong>Results: </strong>Eight patients were included, four of whom were treated through a single-incision anterolateral approach. Average age was 13 years. Average time of the final clinical follow-up was 21 months, with a radiographic follow-up of 11 months. Five fractures were classified as Dubberly type 2A, two as type 3A, and one as type 3B. At the final follow-up, average elbow range of motion and visual analogue scale pain scores were 3-137 degrees and 0.28 (range: 0-2), respectively. PROMIS scores demonstrated an average mobility score of 55 (SD: 8), pain interference of 35 (SD: 5), and pediatric upper-extremity score of 55 (SD: 4). One patient with sickle cell disease developed avascular necrosis of the capitellum. There were no other postoperative complications.</p><p><strong>Conclusions: </strong>Short-term clinical outcomes reveal low pain scores, near normal elbow motion, radiographic and clinical union, and normal patient-reported outcome measures in operatively treated coronal shear fractures of the distal humerus in adolescent patients. A single-incision anterolateral approach offers visualization of the anterior articular surface while respecting posterior soft tissues and the olecranon apophysis.</p><p><strong>Type of study/level of evidence: </strong>Therapeutic V, case series.</p>","PeriodicalId":54815,"journal":{"name":"Journal of Hand Surgery-American Volume","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143016622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Association of Ultrasound and Electrodiagnostic Studies in Patients Evaluated for Ulnar Neuropathy.","authors":"Soun Sheen, David Speach, Courtney M C Jones, Mattie E Raiford, Warren C Hammert","doi":"10.1016/j.jhsa.2024.12.004","DOIUrl":"https://doi.org/10.1016/j.jhsa.2024.12.004","url":null,"abstract":"<p><strong>Purpose: </strong>Our goal was to determine the association between the severity of electrodiagnostic (EDX) studies with the cross-sectional area (CSA) of the ulnar nerve at the cubital tunnel using diagnostic ultrasound. Based on our clinical experience, we hypothesized there would not be a positive correlation between the severity of EDX and ulnar nerve CSA.</p><p><strong>Methods: </strong>This was a retrospective analysis of patients 18 years or older evaluated from May 1, 2020, to June 31, 2021, referred for an upper limb EDX and neuromuscular ultrasound to evaluate for an upper limb neuropathy. History, physical examination, ultrasound imaging (ulnar nerve at elbow), and EDX were reviewed. Patients were excluded for age under 18 years or concomitant upper limb radiculopathy. Baseline sample characteristics were analyzed, including age, race, sex, ethnicity, body mass index (normal, overweight, obese, or morbid obesity), and smoking status.</p><p><strong>Results: </strong>Of 1,043 patients, there were more females than males (634 vs 409) with an average age (SD) of 54.0 (15.5). Most of the patients were White (863) compared to Black (113) and other races (67). The average CSA of the ulnar nerve at the elbow increased with increased severity based on EDX results. There was a significant association between increasing severity on EDX and the increased nerve CSA at the elbow.</p><p><strong>Conclusions: </strong>We found a positive association between the EDX severity and the CSA of the ulnar nerve on diagnostic ultrasound at the cubital tunnel. As the severity of ulnar neuropathy at the elbow increases, the CSA of the ulnar nerve correspondingly increases at the elbow.</p><p><strong>Type of study/level of evidence: </strong>Prognostic II.</p>","PeriodicalId":54815,"journal":{"name":"Journal of Hand Surgery-American Volume","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142967334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Opioid-Sparing Protocols in Hand Surgery: Successes and Opportunities.","authors":"Jonathan Lawson, Michael Grzelak, Roland Zama, Jennifer Waljee, Aviram M Giladi","doi":"10.1016/j.jhsa.2024.11.026","DOIUrl":"https://doi.org/10.1016/j.jhsa.2024.11.026","url":null,"abstract":"<p><p>The opioid epidemic has been a defining crisis in American health care. Many attempts to address the epidemic have focused on issues around opioid prescribing. Legislation at the state and federal levels has been passed; however, the results from these policies have been mixed. Changes to prescription workflows alongside patient and provider education have also had some success. Within hand surgery in particular, recent progress has been made toward promoting opioid-sparing regimens for postoperative pain, including nonopioid and limited-opioid protocols. These regimens offer promise particularly in the setting of ambulatory surgeries, especially soft tissue procedures, and potentially in more invasive and complicated surgical settings. However, there are downsides and failures from these protocols that must be addressed, such as limited data on bony and complex soft tissue procedures, minimal diversity on published alternatives for limited regimens, and times when multimodal approaches are not adequate. Future work should focus on developing opioid-sparing protocols for more complex procedures as well as identifying patients at risk of requiring more comprehensive pain management approaches even for relatively minor procedures.</p>","PeriodicalId":54815,"journal":{"name":"Journal of Hand Surgery-American Volume","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142967341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anatomical Characterization of the Motor Branch to the Fourth Lumbrical: A Cadaver Study.","authors":"Harvey Chim, Ramin Shekouhi, Syeda Hoorulain Ahmed, Chihiro Matsui, Peter Vonu, Brianne Sullivan","doi":"10.1016/j.jhsa.2024.11.023","DOIUrl":"https://doi.org/10.1016/j.jhsa.2024.11.023","url":null,"abstract":"<p><strong>Purpose: </strong>The branching pattern of the deep motor branch of the ulnar nerve (DBUN) in the hand is complex. The anatomy of the motor branch innervating the fourth lumbrical (4L), where paralysis results in a claw hand deformity after ulnar nerve injury, is not well defined. This cadaver study focused on mapping and defining anatomical landmarks in relation to the motor branch to the 4L.</p><p><strong>Methods: </strong>Ten fresh-frozen cadaver hands were dissected. The DBUN was exposed and followed distally, identifying all motor branches, until the branch to the 4L was seen. The small finger flexor tendons were reflected distally to enable visualization of the entire 4L motor branch and its distal entry point. The origin of the 4L motor branch was mapped in relation to fixed anatomical landmarks in the hand.</p><p><strong>Results: </strong>A consistent motor branch to the 4L and third palmar interosseous (3PI) muscles was seen originating from the DBUN in all specimens. The mean number of motor branches innervating the hypothenar muscles proximal to the 4L/3PI motor branch was 2.1 (range 1 to 5). The mean distance from the origin of the DBUN to the 4L/3PI motor branch was 2.9 cm (range 2.5 to 4.2 cm). The mean length of the 4L/3PI branch was 3.1 cm (range 2.3 to 4.5 cm). In seven specimens, the 4L/3PI branch demonstrated an intramuscular course through the 3PI before terminating in the 4L. In three specimens the 4L/ 3PI branch ran on the volar surface of the 3PI before terminating in the 4L.</p><p><strong>Conclusions: </strong>A consistent 4L/3PI motor branch was mapped and characterized in all specimens.</p><p><strong>Clinical relevance: </strong>These findings provide a guide for intraoperative localization of the 4L/3PI motor branch and also may provide further evidence to explain findings seen after distal nerve transfers to treat ulnar nerve injury.</p>","PeriodicalId":54815,"journal":{"name":"Journal of Hand Surgery-American Volume","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142967328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}