The purpose of this study was to compare two sources of nerve graft for brachial plexus reconstruction: the denervated superficial branch of the radial nerve (SBRN) and the sural nerve. Ninety-seven patients who underwent brachial plexus reconstruction with denervated SBRN nerve (24 patients with 24 grafts) or with sural nerve grafting (73 patients with 83 nerve grafts) were included. The two groups were compared with respect to postoperative muscle reinnervation, disabilities of the arm, shoulder, and hand (DASH) scores. In the SBRN group, only four (17%) of the nerve grafts provided grade III or higher muscle function. In the sural nerve group, 31 (37%) of the nerve grafts provided grade III or higher muscle function. Smoking had a negative impact on muscle recovery. Denervated SBRN grafts are associated with inferior outcomes when compared with sural nerve grafts in the treatment of traumatic adult brachial plexus injuries. (Journal of Surgical Orthopaedic Advances 33(2):080-083, 2024).

OBJECTIVE: Although ipsilateral C7 nerve transfer is used for the treatment of C5-C6 brachial plexus injuries, accurately evaluating the functional quality of the donor nerve (ipsilateral C7 nerve root) is difficult, especially when the C7 nerve root is slightly injured. The purpose of this study was to determine the indicators to evaluate the quality of the ipsilateral C7 nerve and assess the clinical outcomes of this procedure.
METHODS: This study employed the following three indicators to assess the quality of the ipsilateral C7 nerve: (1) the muscle strength and electrophysiological status of the latissimus dorsi, triceps brachii, and extensor digitorum communis; (2) the sensibility of the radial three digits, especially the index finger; and (3) the intraoperative appearance, feel and electrophysiological status of the ipsilateral C7 nerve root. Transfer of the ipsilateral C7 nerve root to the upper trunk was implemented only when the following three tests were conducted, the criteria were met, and the clinical outcomes were assessed in eight patients with C5-C6 brachial plexus injuries.
RESULTS: Patients were followed-up for an average of 90 ± 42 months. At the final follow-up, all eight patients achieved recovery of elbow flexion, with five and three patients scoring M4 and M3, respectively, according to the Medical Research Council scoring. The shoulder abduction range of motor recovery averaged 86 ± 47° (range, 30°-170°), whereas the shoulder external rotation averaged 51 ± 26° (range, 15°-90°).
CONCLUSIONS: Ipsilateral C7 nerve transfer is a reliable and effective option for the functional reconstruction of the shoulder and elbow after C5-C6 brachial plexus injuries when the three prerequisites are met.

OBJECTIVE: Restoration of pinch and grasp is a chief concern of patients with cervical spinal cord injury or peripheral nerve injury involving the anterior interosseous nerve (AIN). We hypothesize that supinator nerve-to-AIN (Sup-AIN) nerve transfer is a viable option for AIN neurotization.
METHODS: We performed a retrospective review of patients who received Sup-AIN. Reported outcomes included Medical Research Council strength of the flexor digitorum profundus and flexor pollicis longus and passive range of digit motion. Patients with <12 months of follow-up were excluded.
RESULTS: Eleven patients underwent Sup-AIN, eight with peripheral nerve injury, and three with spinal cord injury. Three patients were excluded because of insufficient follow-up. Average follow-up was 17 months (range: 12-25 months). Six patients had M4 recovery (75%), one patient had M3 recovery (12.5%), and one did not recover function because of severe stiffness (12.5%). We observed no complications or donor site morbidity in our patients.
CONCLUSIONS: The Sup-AIN nerve transfer is an effective option to restore digital flexion in patients with peripheral nerve injury or spinal cord injury involving the AIN motor distribution. In comparison to previously described extensor carpi radialis brevis to AIN and brachialis to AIN nerve transfers, Sup-AIN offers the benefits of a more expendable donor nerve and shorter regenerative distance, respectively. The one failed Sup-AIN in our series highlights the importance of patient selection.
METHODS: Therapeutic V.

BACKGROUND: Peripheral nerves consist of axons and connective tissue. The amount of connective tissue in peripheral nerves such as the brachial plexus varies proximally to distally. The proximal regions of the brachial plexus are more susceptible to stretch injuries than the distal regions. A description of the mechanical behavior of the peripheral nerve components is necessary to better understand the deformation mechanisms during stretch injuries. The purpose of this study was to model the biomechanical behavior of each component of the peripheral nerves (fascicles, connective tissue) in a cadaveric model and report differences in elastic modulus, maximum stress and maximum strain.
METHODS: Forty-six specimens of fascicles and epi-perineurium were subjected to cyclical uniaxial tensile tests to obtain the stress and strain histories of each specimen, using a BOSE® Electroforce® 3330 and INSTRON® 5969 materials testing machines. Maximum stress, maximum strain and elastic modulus were extracted from the load-displacement and stress-strain curves, and analyzed using Mann-Whitney tests.
RESULTS: Mean elastic modulus was 6.34 MPa for fascicles, and 32.1 MPa for connective tissue. The differences in elastic modulus and maximum stress between fascicles and connective tissue were statistically significant (p < 0.001).
CONCLUSIONS: Peripheral nerve connective tissue showed significantly higher elastic modulus and maximum stress than fascicles. These data confirm the greater fragility of axons compared to connective tissue, suggesting that the greater susceptibility to stretch injury in proximal regions of the brachial plexus might be related to the smaller amount of connective tissue.

Objective: To investigate the clinicopathological and genetic characteristics of neuromuscular choristoma-associated desmoid type fibromatosis (NMC-DF). Methods: The clinical morphological and immunohistochemical features of 7 NMC-DF cases diagnosed from January 2013 to January 2023 in Beijing Jishuitan Hospital were retrospectively analyzed. A series of neuromuscular choristoma and neuromuscular choristoma-associated desmoid type fibromatosis were evaluated for CTNNB1 mutations, and hotspot mutations for CTNNB1 were tested in 4 NMC-DF cases using Sanger sequencing. Results: The tumors were collected from 3 females and 4 males, aged 1 to 22 years (mean 7.1 years), involving the sciatic nerve (n=4), brachial plexus (n=2) or multiple nerves (n=1). The course of the disease spanned from 3 months to 10 years. Two cases were recurrent tumors. All the 7 NMC cases showed endoneurial intercalation of mature skeletal muscle fibers among the peripheral nerve fascicles, and the histologic features of the NMC-DF were strikingly similar to the conventional desmoid-type fibromatosis. By immunohistochemistry, all NMC and NMC-DF cases showed aberrant nuclear staining of β-catenin (7/7), the muscle cells in NMC were intensely immunoreactive for desmin, and the admixed nerve fibers were highlighted by NF and S-100 (7/7). Four NMC and NMC-DF had CTNNB1 mutations, 3 c.121A>G (p.T41A) and 1 c.134C>T (p.S45F). Follow-up of the 7 cases, ranging from 22 to 78 months, showed tumor recurrence in 2 patients at 3 and 8 months respectively after the first surgical resection, of which 1 patient underwent above-knee amputation. No recurrence occurred in other cases with tumor excision and neurological reconstruction surgery. There was no metastasis occurred in the 7 cases. Conclusions: NMC is a rare congenital lesion with differentiated mature skeletal muscle tissue found in peripheral nerve fascicles, and approximately 80% of patients with NMC develop a soft tissue fibromatosis. CTNNB1 mutation in the Wnt signaling pathway may be involved in the pathogenesis of NMC and NMC-DF, and S45F mutations seems to have a higher risk of disease progression.
目的： 探讨神经肌肉迷芽瘤相关的韧带样型纤维瘤病（neuromuscular choristoma-associated desmoid type fibromatosis，NMC-DF）临床病理及分子遗传学特征。 方法： 收集北京积水潭医院2013年1月至2023年1月明确诊断为NMC-DF的病例7例，对其临床、组织形态及免疫组织化学特点进行回顾性分析，采用Sanger测序法对4例患者的神经肌肉迷芽瘤（neuromuscular choristoma，NMC）及韧带样型纤维瘤病（desmoid type fibromatosis，DF）标本分别进行检测，明确CTNNB1基因的突变类型。 结果： 7例患者中女性3例，男性4例，年龄1~22岁，平均年龄7.1岁。病程3个月到10年不等。2例为复发后就诊病例。肿瘤位于大腿3例，小腿1例，上臂1例，颈部1例，影像学提示7例肿瘤均有相应部位神经增粗，4例为坐骨神经，1例为坐骨神经、胫神经、腓总神经全程瘤样增粗，2例为臂从神经，肿瘤与病变神经关系密切。7例病变的神经束内可见骨骼肌纤维，残存的神经纤维穿插其中，呈神经肌肉迷芽瘤的结构；肿瘤均具有典型的韧带样型纤维瘤病结构。免疫组织化学，NMC中部分肌纤维细胞核表达β-catenin（7/7），肌纤维结蛋白弥漫阳性，神经纤维神经丝蛋白和S-100蛋白阳性（7/7）；NMC-DF中β-catenin在肿瘤细胞核中呈散在阳性（7/7）。CTNNB1基因Sanger测序，3例c.121A>G（p.T41A）突变，1例c.134C>T（p.S45F）突变。7例获得随访资料，随访时间22~78个月，2例为复发后就诊，其中1例截肢后再次复发，其余无进展。 结论： NMC是一种罕见的神经发育畸形性病变，神经干内可见异位的骨骼肌纤维，约80%的病例在病变神经周围软组织内伴发DF，组织形态与经典的DF相同，Wnt信号通路中的CTNNB1基因突变与二者的发生发展密切相关，CTNNB1 c.134C>T（p.S45F）突变可能提示不良预后。.

BACKGROUND: The proximal regions of the brachial plexus (roots, trunks) are more susceptible to permanent damage due to stretch injuries than the distal regions (cords, terminal branches). A better description of brachial plexus mechanical behavior is necessary to better understand deformation mechanisms in stretch injury. The purpose of this study was to model the biomechanical behavior of each portion of the brachial plexus (roots, trunks, cords, peripheral nerves) in a cadaveric model and report differences in elastic modulus, maximum stress and maximum strain.
METHODS: Eight cadaveric plexi, divided into 47 segments according to regions of interest, underwent cyclical uniaxial tensile tests, using a BOSE® Electroforce® 3330 and INSTRON® 5969 material testing machines, to obtain the stress and strain histories of each specimen. Maximum stress, maximum strain and elastic modulus were extracted from the load-displacement and stress-strain curves. Statistical analyses used 1-way ANOVA with post-hoc Tukey HSD (Honestly Significant Difference) and Mann-Whitney tests.
RESULTS: Mean elastic modulus was 8.65 MPa for roots, 8.82 MPa for trunks, 22.44 MPa for cords, and 26.43 MPa for peripheral nerves. Differences in elastic modulus and in maximum stress were statistically significant (p < 0.001) between proximal (roots, trunks) and distal (cords, peripheral nerves) specimens.
CONCLUSIONS: Proximal structures demonstrated significantly smaller elastic modulus and maximum stress than distal structures. These data confirm the greater fragility of proximal regions of the brachial plexus.

OBJECTIVE: Peripheral nerve sheath tumors (PNSTs) are rare in pediatric patients, especially in the brachial plexus. Research on PNSTs is lacking. This article presents a retrospective cohort study of pediatric patients diagnosed and treated with PNSTs, specifically brachial plexus tumors.
METHODS: All pediatric patients intervened in a single center between 2007 and 2023 with brachial plexus tumors were systemically analyzed.
RESULTS: Eleven pediatric patients with 14 brachial plexus PNSTs were studied. The gender distribution was 64% female and 36% male, with an average age of 10.7 years. Ninety-one percent had a previous NF-1 diagnosis. Right brachial plexus presented a higher prevalence (64%). Pain, Tinel\'s sign, and stiffness masses were common during diagnosis. Motor deficits were noted in 43% of the patients. Surgery was indicated for symptoms, particularly pain and rapid growth, increasing malignancy risk. Due to suspected malignancy, an en bloc resection with safety margins was performed. Among the patients, 57% received a histopathological diagnosis of MPNST (malignant peripheral nerve sheath tumor). Treatment included radiotherapy and chemotherapy. Clinical follow-up was conducted for all cases, involving clinical and oncological evaluations for all MPNSTs.
CONCLUSIONS: This article present a series of pediatric brachial plexus tumors, especially in NF-1, and emphasizes the importance of thorough evaluation for this group. Swift diagnosis is crucial in pediatrics, enabling successful surgery for small lesions with limited neurological symptoms, improving long-term outcomes. Prompt referral to specialized services is urged for suspected masses, irrespective of neurological symptoms. Benign tumor postsurgical progression shows better outcomes than MPNSTs, with complete resection as the primary goal. Needle-guided biopsy is not recommended.

BACKGROUND: Understanding patterns of peripheral nerve injuries (PNIs) and brachial plexus injuries (BPIs) is essential to preventing and appropriately managing nerve injuries. We sought to assess the incidence, cause, and severity of PNIs and BPIs sustained by patients with trauma.
METHODS: We conducted a retrospective review of the Trauma Registry Database (January 2002 to December 2020) to identify patients with PNIs or BPIs.
RESULTS: We evaluated data from 24 905 patients with trauma; 335 (1.3%) sustained PNIs (81% male; mean age 36 yr, standard deviation [SD] 16 yr) and 64 (0.3%) sustained BPIs (84% male; mean age 35, SD 15 yr). Nerves in the upper extremities were more commonly affected than those in the lower extremities. Sharp injuries (39.4%) and motorcycle accidents (32.8%) were the most frequent causes of PNIs and BPIs, respectively. Other common causes of PNI were motor vehicle collisions (16.7%) and gunshot wounds (12.8%). Many patients with PNIs (69.0%) and BPIs (53%) underwent operative management. The most frequent reconstruction for PNI was primary nerve repair (66%), while nerve transfers (48%) were more frequently used for BPI.
CONCLUSIONS: Nerve injuries in the trauma population have decreased over the last 3 decades with shifts in mechanisms of injury and use of imaging, electrodiagnostic tests, and surgery. Nerve injuries are often complex and time-sensitive to treat; understanding changes in trends is important to ensure optimal patient management.

Teaching point: Magnetic resonance imaging (MRI) has significantly improved the evaluation of brachial plexus injuries, offering new possibilities for microsurgical repair and contributing to the functional prognosis.

BACKGROUND: Although a common injury there is a lack of published primary data to inform clinical management of sports related brachial plexus injuries.
METHODS: A systematic search was completed in Medline, CINAHL, PubMed, SPORTDiscus and Web of Science databases and Google Scholar from inception to August 2023 according to the PRISMA-ScR guidelines. Methodological quality assessment of included articles was with the Joanna Briggs Institute tool. Studies providing primary data as to the rehabilitative management of diagnosed or suspected brachial plexus injuries sustained when playing contact sports were included.
RESULTS: Sixty-five studies were identified and screened, of which, 8 case reports were included, incorporating 10 participants with a mean age of 19.8 (±4.09) years. There was wide heterogeneity in injury severity, injury reporting, physical examination and imaging approaches documented. 9 of 10 participants returned to competitive sports, though follow-up periods also varied widely. Whilst return to play criteria varied between studies, the most consistent indicator was pain-free shoulder range of motion and strength.
CONCLUSIONS: There is a distinct lack of data available to inform evidence-based rehabilitation management of sports related brachial plexus injury. Only 8 individual case reports contain published data reporting on 10 athletes. Further reporting is critical to inform clinical management.