Spinner, Robert J.

OBJECTIVE Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive sarcomas commonly associated with neurofibromatosis type 1 (NF1), whose occurrence in schwannomatosis remains poorly understood. This study aimed to characterize MPNSTs in NF type 2 (NF2)– and SMARCB1-related schwannomatosis through a systematic review and meta-analysis of survival outcomes. METHODS A comprehensive search of the PubMed, Embase, Scopus, SEER (Surveillance, Epidemiology, and End Results), and Web of Science databases was conducted from database inception through January 2024. Clinical, radiological, histopathological, and treatment data were extracted. Primary endpoints included overall survival (OS) and progression-free survival (PFS). Predictors of outcomes were analyzed using Kaplan-Meier survival curves and Cox proportional hazards models. RESULTS A total of 39 cases were identified. NF2-related disease accounted for 67% of cases, while 28% were SMARCB1 related. The mean age at MPNST diagnosis was 33 years (range 9–79 years). Pain (41%) and weakness (26%) were the most common presenting symptoms. The mortality rate was 72.9%. No tumors were associated with LZTR1 mutations. Tumor locations varied widely, with involvement of the pelvis, thigh, skull base, forearm/hand, and cranial nerves. Trends suggested improved survival in the absence of S100 loss, gross-total resection, and a known schwannoma precursor. Conversely, having an intracranial or intraspinal lesion or having NF2 in the setting of prior radiation therapy were found to be associated with decreased survival and increased progression. A risk stratification tool predicted OS (HR 28.0, p < 0.0001) and PFS (HR 12.1, p < 0.0001). CONCLUSIONS MPNSTs, although rare in schwannomatosis, can arise even in the absence of prior radiation exposure and may mimic benign schwannomas. A preliminary risk stratification tool may aid in identifying high-risk patients and optimizing treatment approaches, although validation is needed. Given the aggressive nature of MPNSTs and their potential for delayed diagnosis due to their rarity, vigilant monitoring and individualized treatment strategies are crucial. Future research should focus on refining risk prediction models and exploring targeted therapies for schwannomatosis-associated MPNSTs to improve patient outcomes.

Abstract BACKGROUND CNS ependymal tumors rarely demonstrate mixed subependymal and ependymal pathology. The clinical course of these tumors is difficult to predict, but prior studies have identified TERT mutations and loss of chromosome 6 as poor prognostic factors in these tumors when located in the posterior fossa. METHODS In this retrospective single-institution study, patients with a diagnosis of mixed subependymoma/ependymoma were identified and chart reviewed to describe demographics, pathological findings, treatment courses and clinical outcomes. RESULTS Eleven patients (median age 57, 2 female, 9 male) were identified. Ten tumors were in the posterior fossa and 1 in the cervical spine. At diagnosis, 2 underwent gross total resection, 8 underwent subtotal resection, and 1 was only biopsied. Radiotherapy was administered to 5 patients at initial diagnosis (54Gy in 30 fractions). Systemic therapy (temozolomide and bevacizumab) was administered at recurrence to 2 patients. Loss of chromosome 6 was present in 5 /11 patients and TERT mutations were present in 4/11 patients, with both present in 3/11 patients. Median progression-free survival (mPFS) was 90.1 months (95% CI: 90.1–NA), with 3 progression events observed at 22, 90, and 107 months. Median follow-up duration was 27.9 months. Receiving radiotherapy had a longer mPFS (98 vs 22 months, p=0.15), although non-significant. At the time of data cut-off none of the patients were deceased. CONCLUSIONS Mixed subependymoma/ependymoma is a rare diagnosis with varying clinical outcomes. Our case series demonstrated that the majority of patients did not exhibit the previously identified poor prognostic factors. Although non-significant due to limited case numbers, radiotherapy was suggestive of longer mPFS.

OBJECTIVE Cervical dystonia (or spasmodic torticollis) is a neurological condition that results in abnormal movements and head posture, for which initial surgical intervention typically involves selective denervation of the sternocleidomastoid (SCM) and paraspinal muscles. However, muscle reactivation of the distal SCM stump can result in recurrent symptoms. In this study, the authors present their preliminary experience with distal SCM stump resection following selective denervation, with the aim of evaluating the effectiveness of the procedure and identifying patients who may benefit from this technique. METHODS This is a retrospective single-center cohort study of patients who underwent SCM stump resection as revision surgery for cervical dystonia. RESULTS A total of 18 patients (10 males [56%]) were included with a median (range) age of 54 (40–70) years. All patients received selective denervation of the SCM at the authors’ institution prior to SCM stump resection at a median (range) time of 12 (3–198) months between surgical procedures. At preoperative baseline, 13 patients (72%) possessed a rotational torticollis component to their head deviation, 12 (67%) possessed a laterocollis component, and 2 (11%) possessed a retrocollis component. At the most recent follow-up (median [range] 16 [4–119] months), 6 patients had complete resolution of their cervical dystonia (33%), while 10 had residual deviation (56%) and 2 had recurrent deviation (11%). However, compared to their post–selective denervation head position, 12 patients experienced improvement in their head position (67%), 4 patients had no change in their head position (22%), and 2 had worsening of their cervical dystonia (11%) following SCM stump resection. Importantly, 12 patients experienced improvement in their pain following SCM stump resection (67%). Patients who had a history of other movement/spasmodic disorders were more likely to have improvement in head position and improvement in pain after SCM stump resection, though neither of these results achieved statistical significance (p = 0.054). Additionally, patients who experienced full resolution of their cervical dystonia had shorter time between initial selective denervation surgery and SCM stump resection, though this result also did not achieve statistical significance (p = 0.068). CONCLUSIONS Distal SCM stump resection following selective denervation is a simple, safe, and effective option for many patients in treating refractory cervical dystonia. Patients with more severe preoperative presentations may experience greater benefit from SCM stump resection, though additional investigations are needed.

Case: We present 3 cases of brachial plexus injuries (BPI) secondary to compressive hematomas during extracorporeal membrane oxygenation (ECMO), with follow-up ranging from 18 months to 12 years. Patients exhibited profound upper extremity deficits and underwent variable interventions, including surgical decompression. All demonstrated meaningful neurologic recovery. Conclusion: BPI is a rare but serious complication of ECMO. These cases highlight the importance of early recognition and hematoma evacuation, emphasizing the need for clinical vigilance to optimize neurologic outcomes following hematoma-induced nerve injury.

ABSTRACT At the 42nd Annual Meeting of the American Association of Clinical Anatomists (AACA) in Bellevue, Washington, June 2025, two inaugural events—the Clinical Anatomy Fireside Chat (CAFC) and the Clinical Anatomy Symposium: Head and Neck 2025 (CAS)—fostered rich dialogue on the evolving role and operational definition of clinical anatomy. Experts from various clinical and anatomical disciplines explored the meaning of clinical anatomy, highlighting the absence of a universal definition despite its frequent use in education and research. Through these interdisciplinary discussions, a consensus emerged: clinical anatomy is not defined solely by the possession of clinical credentials but by the integration of anatomical knowledge and clinical relevance, achieved most effectively through collaboration. Clinical anatomy education and research require different depths of clinical knowledge depending on the audience and objective, and meaningful collaboration can bridge gaps in expertise. The symposium further illustrated that high‐quality clinical anatomy emerges from mutual respect and reciprocal insight between clinicians and anatomists. This article presents a consensus statement developed by AACA representatives and invited speakers, affirming that collaboration is not only foundational to the practice of clinical anatomy but also fundamental to its definition. These conclusions aim to guide future educational models, research strategies, and interdisciplinary partnerships in the field of clinical anatomy.

Background: Chronic hamstring tears can result in challenging surgical repairs. Allografts may be used to augment the repair; however, there is limited clinical evidence supporting their use. Purposes: To (1) evaluate clinical outcomes of patients who underwent proximal hamstring repair with allograft augmentation or interposition and (2) compare them to matched controls who underwent primary hamstring repair. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 117 patients who underwent proximal hamstring repair were included, consisting of 19 allograft augmentations, 20 allograft interpositions, and 78 primary repairs. Allograft cohorts were propensity-matched with those who underwent primary repair in a 1 to 2 ratio. Clinical outcomes were obtained at the final follow-up. Data were extracted using continuous variables, with normality reported as mean values ± standard deviation, and non-normality reported as median values with interquartile ranges (IQR). Results: The median follow-up of the augmentation cohort was 1.9 [IQR, 0.8-3.9] years, while it was 3.2 [IQR, 1.6-5.1] years ( P = .182) for the primary repair cohort. The mean follow-up for the interposition cohort was 3.5 ± 2.4 years, while it was 4.2 ± 2.5 years for the primary repair cohort ( P = .227). Forty-two percent of the augmentation cohort had undergone previous surgery, compared with 5% of the interposition cohort. The time from injury to surgery for the augmentation and primary repair cohorts was 6.4 and 1.3 months, respectively ( P < .001). For the interposition and primary repair cohorts, the durations were 17.8 and 1 months, respectively ( P < .001). Clinical outcomes, including the Tegner Activity Scale (3 vs 3), pain with activity (47.4% vs 23.7%), and muscle spasms (36.8% vs 26.3%), did not show significant differences between the augmentation and primary repair cohorts. The augmentation cohort had a significantly worse Lower Extremity Functional Scale (LEFS) score (64 vs 75; P < .001) and were more likely to experience pain with sitting (52.6% vs 21.1%; P = .034) than the primary repair cohort. There was no significant difference in clinical outcomes between the interposition and primary repair cohorts (LEFS: 69 vs 75.5, Tegner Activity Scale: 4 vs 4; pain with sitting: 26.3% vs 27.5%; pain with activity: 42.1% vs 30%; muscle spasms: 26.3% vs 30%). Revision rates were similar between cohorts ( P ≥ .255). Conclusion: Proximal hamstring repair for chronic tears with allograft augmentation or interposition is a reproducible procedure that results in satisfactory, yet poorer clinical outcomes compared with patients who underwent primary hamstring repair. These procedures should be considered in symptomatic patients with chronic tears that are not amenable to primary repair.

OBJECTIVE Resection of common peroneal nerve (CPN) schwannomas is generally believed to be associated with a high risk of postoperative deficit, especially the chance for development of a foot drop. The goal of this study was to investigate the surgical results for resection of schwannomas from the CPN around the knee and specifically the chance of developing a postoperative motor deficit. METHODS Data from 36 patients with sporadic schwannomas and 8 patients with schwannomatosis (12 schwannomas total) treated at two centers were retrospectively analyzed. For sporadic cases, different locations around the knee were compared (i.e., proximal to the fibular head [FH], at the FH, and distal to the FH), taking into account the preoperative duration of symptoms, size at presentation, and surgical results of resection. The literature was systematically reviewed for reported cases by searching the PubMed and Embase databases. RESULTS A total of 24 schwannomas proximal to the FH were surgically treated: 11 at the FH, and 13 distal to the FH. For the entire cohort, the mean size of CPN schwannomas distal to the FH at presentation was smaller (1.4 × 1.8 cm) compared with those proximal to (2.0 × 2.2 cm) and at (2.2 × 2.3 cm) the FH, although these differences were not statistically significant. The mean preoperative duration of symptoms was slightly longer for schwannomas distal to the FH (35 months) than for those proximal to the FH (21 months) and at the FH (27 months); however, this difference was not significant. Postoperative deficits occurred in 3 sporadic cases: 2 patients with temporary weakness (Medical Research Council grade 4) that completely resolved within several months and 1 patient who had previously undergone surgery elsewhere and presented with deficits and in whom weakness increased after resection. Improvement in preoperative deficits was observed in 1 patient with extensor hallucis longus muscle paralysis that completely recovered. One patient with schwannomatosis developed muscle weakness after resection of a plexiform schwannoma. A systematic review of 21 previously reported cases in the literature showed that larger CPN schwannomas (> 5 cm) were more likely to result in permanent motor deficits. CONCLUSIONS This retrospective study of 44 patients shows that peroneal nerve schwannomas around the knee can be safely removed with a low risk of deficits. The systematic review of the literature suggests that larger schwannomas are more likely to result in permanent deficit. In the authors’ opinion, CPN schwannomas can best be resected, preferably when the lesion is relatively small.