Advances in Imaging of Compressive Neuropathies.

Ultrasound and magnetic resonance neurography are useful modalities to aid in the assessment of compressive neuropathies, although they are still limited in their resolution of nerve microstructure and their capacity to monitor postoperative nerve recovery. Optical coherence tomography, a preclinical imaging modality, is promising in its ability to better identify structural and potential physiologic changes to peripheral nerves, but requires additional testing and research prior to widespread clinical implementation. Further advances in nerve imaging may elucidate the ability to visualize the zone of nerve injury intraoperatively, monitor the progression of nerve regeneration, and localize problems during nerve recovery.

Posttraumatic Compressive Neuropathy of the Deep Motor Branch of the Ulnar Nerve Caused by Heterotopic Ossification.

We report a case of posttraumatic compressive neuropathy of the deep motor branch of the ulnar nerve occurring in the setting of heterotopic ossification following a direct blow to the hypothenar eminence. Over several weeks, the patient developed ring and little finger claw deformities and atrophy of his first dorsal interosseous and adductor pollicis muscles with sparing of sensation. Electromyography and nerve conduction study localized the area of injury, and computed tomography confirmed the presence of heterotopic bone near the deep motor branch of the ulnar nerve. Intraoperatively, the deep motor branch of the ulnar nerve was under tension as it traversed volarly over the hook of hamate and heterotopic bone. Decompression of the deep motor branch of the ulnar nerve with resection of heterotopic bone and the hook of hamate was performed. Six months postoperatively, the patient demonstrated resolution of clawing and improving strength of his ulnar nerve innervated intrinsic muscles.

Foreign substance injection for esthetic purposes associated with delayed unilateral sciatic nerve impairment: A surgical case report.

Attempts at body contour modifications have led to the use of different alloplastic materials that can irreversibly damage health and risk patients' lives. These modeling substances can induce a general autoimmune inflammatory response, producing a very heterogeneous clinical spectrum ranging from mild and severe systemic to local symptoms that sometimes affect peripheral nerves. We report a unique case of a tumor-like sciatic nerve impairment produced months after the injection of a modeling substance into the buttocks for esthetic purposes. The patient was treated with a surgical decompression of the sciatic nerve that encompassed the removal of the injected mass. This approach ultimately yielded a complete neurological recovery of the affected nerve. We emphasize the diagnostic approach and surgical management employed in this unique case and review the current literature on this infrequent complication.

Popliteal Cyst Compressive Tibial Neuropathy and Venous Insufficiency: A Case Report.

Popliteal cysts are a collection of synovial fluid found in the popliteal fossa that typically form in adults in association with traumatic injuries, degenerative conditions, or inflammatory arthritis of the knee. While often asymptomatic, popliteal cysts may become problematic as enlarging and ruptured cysts may compress surrounding neurovascular structures, resulting in lower extremity edema or peripheral neuropathy. We report a unique case of a symptomatic popliteal cyst in a patient with both compressive neuropathy and venous congestion in the setting of a non-ruptured popliteal cyst after a surgically repaired intraarticular injury. Magnetic resonance imaging (MRI) showed a synovial cyst abutting the posterior neurovascular bundle and evidence of avascular necrosis. An open posterior cyst decompression was done, and the patient was able to report significant symptomatic improvement over the course of two weeks postoperatively. The previously noted varicose veins also demonstrated noticeable resolution. While relatively common, popliteal cysts may require prompt surgical decompression in order to provide effective symptomatic relief.

Recurrence of ulnar tunnel syndrome: Long-term clinical and functional results of surgical management using revision neurolysis and subcutaneous anterior transposition.

OBJECTIVE: Recurrence after primary ulnar tunnel syndrome surgery is observed in 1.4%-25% of patients. However, the outcome of revision surgery is uncertain and limited. This study aimed to assess the clinical and functional outcomes of neurolysis combined with anterior subcutaneous transposition in cases of recurrence. PATIENTS AND METHODS: This retrospective single-center study included patients who were operated on for iterative ulnar tunnel syndrome at the elbow between January 1996 and December 2020, with a minimum follow-up of 24 months. Demographic data, pre- and post-operative clinical evaluations, surgical details, and satisfaction levels were collected. RESULTS: Twenty-eight patients were reviewed. Mean follow-up was 11.7 years (range, 2.1-26.4 years). The secondary procedure led to significant improvement in mean Quick-DASH score, from 25.3 (range, 11-50) to 20.0 (range, 11-49) (p = 0.023), with a satisfaction rate of 78.5%. Symptoms of pain (p = 0.033), amyotrophy (p = 0.013), hypoesthesia (p < 0.01), and paresthesia (p < 0.001) also showed significant improvement. There were 7 cases of failure (25.0%). CONCLUSION: The combination of neurolysis and anterior subcutaneous transposition was a reliable technique, improving clinical outcome in recurrent ulnar tunnel syndrome after previous surgery. LEVEL OF EVIDENCE: IV - retrospective study.

Evaluation of Different Surgical Techniques for Revision Cubital Tunnel Release: A Meta-Analysis of Patient-Reported Symptoms.

PURPOSE: Controversy exists regarding the best option for revision surgery in refractory cubital tunnel syndrome (CuTS). The purpose of this systematic review was to evaluate the effectiveness of revision surgery and determine the optimal surgical approach for patients requiring revision surgery for CuTS. METHODS: A literature search was conducted. Characteristics of the included studies were summarized descriptively. The risk ratio between patient-reported preoperative and postoperative outcomes relating to pain, motor, and sensory deficits was calculated. A meta-regression analysis was performed to evaluate the postoperative symptom improvements based on the type of secondary surgery. Random-effects meta-analysis and descriptive statistics were used when appropriate. RESULTS: A total of 471 patients were evaluated in 20 studies. In total, 254 (53.9%) male and 217 (46.1%) female patients, with an average age of 49.2 ± 14.1 years, were included in this study. Pain was the most common symptom (n = 346, 81.6%), followed by sensory and motor dysfunction in 342 (80.6%) and 223 (52.6%) patients, respectively. Meta-analysis comparing preoperative and postoperative symptoms between patients who had submuscular transposition (SMT), subcutaneous transposition (SCT), and neurolysis showed that a significant subgroup difference exists between the types of revision surgery in sensory and motor improvements. Meta-regression showed that SMT was associated with better outcomes compared with SCT in motor and sensory improvements. CONCLUSIONS: Revision surgery for CuTS can be useful for addressing recurrent and persistent symptoms. Compared with neurolysis and SCT, SMT seems to be the superior option for revision surgery, demonstrating substantial improvement in all symptom domains. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Unilateral foot drop due to prone positioning in COVID-19: A case report.

Key Clinical Message: Understanding the complications arising from prone positioning following mechanical ventilation during management of acute respiratory distress from COVID-19. Abstract: Acute respiratory distress syndrome (ARDS) resulting from coronavirus disease 2019 (COVID-19) has been one of the well-known complications of the disease since it was first reported in 2020. Mechanical ventilation for severe ARDS has been widely utilized for the management of such patients. Prone positioning (PP) is associated with improved oxygenation and overall outcomes in both intubated and non-intubated patients. However, there are several complications associated with this procedure, including compressive neuropathies. In this article, we report a case of unilateral foot drop following mechanical ventilation and PP during the management of ARDS from COVID-19.

Supracondylar Apophysis of the Humerus: Rare Cause of High Compression of the Median Nerve.

Supracondylar apophysis (SA) is a bony prominence that originates from the anteromedial aspect of the distal humerus with a lower projection and which, although usually asymptomatic, due to the relationship with adjacent structures can cause symptoms. We describe the case of a 42-year-old woman with pain complaints radiating from her elbow to her hand, with 6 months of evolution. On objective examination, the patient had a sensory deficit in the median nerve territory and decreased grip strength. Radiographs of the distal humerus were performed, in which a bone spike was visible, and magnetic resonance imaging showed thickening of the median nerve epineurium. Electromyography showed severe axonal demyelination of the median nerve proximal to the elbow. A median nerve compression caused by a SA was diagnosed. The patient underwent surgery and, 1 year after the operation, she had a complete clinical recovery. Supracondylar apophysis is a rare, but possible and treatable cause of high median nerve compression.

Supracondylar Apophysis of the Humerus: Rare Cause of High Compression of the Median Nerve / Apófise supracondilar do úmero: Causa rara de compressão alta do nervo mediano

Abstract Supracondylar apophysis (SA) is a bony prominence that originates from the anteromedial aspect of the distal humerus with a lower projection and which, although usually asymptomatic, due to the relationship with adjacent structures can cause symptoms. We describe the case of a 42-year-old woman with pain complaints radiating from her elbow to her hand, with 6 months of evolution. On objective examination, the patient had a sensory deficit in the median nerve territory and decreased grip strength. Radiographs of the distal humerus were performed, in which a bone spike was visible, and magnetic resonance imaging showed thickening of the median nerve epineurium. Electromyography showed severe axonal demyelination of the median nerve proximal to the elbow. A median nerve compression caused by a SA was diagnosed. The patient underwent surgery and, 1 year after the operation, she had a complete clinical recovery. Supracondylar apophysis is a rare, but possible and treatable cause of high median nerve compression.

Resumo A apófise supracondilar (ASC) é uma proeminência óssea que tem origem na face anteromedial do úmero distal com projeção inferior e que, apesar de habitualmente assintomática, pela relação com as estruturas adjacentes pode causar sintomatologia. Descrevemos o caso de uma mulher de 42 anos, com queixas álgicas irradiadas do cotovelo à mão, com 6 meses de evolução. Ao exame objetivo, a paciente apresentava um déficit sensorial no território do nervo mediano e diminuição da força de preensão. Foram realizadas radiografias do úmero distal nas quais era visível uma espícula óssea, e na ressonância magnética era evidente o espessamento do epineuro do nervo mediano. A eletromiografia apresentou uma desmielinização axonal grave do nervo mediano proximal ao cotovelo. Foi diagnosticada uma compressão do nervo mediano por uma ASC. A paciente foi submetida à cirurgia e 1 ano pós-operatório apresentou recuperação clínica total. A ASC é uma causa rara, mas possível e tratável da compressão alta do nervo mediano.

Adipose-derived stem cells modulate neuroinflammation and improve functional recovery in chronic constriction injury of the rat sciatic nerve.

Introduction: Compressive neuropathy, a common chronic traumatic injury of peripheral nerves, leads to variable impairment in sensory and motor function. Clinical symptoms persist in a significant portion of patients despite decompression, with muscle atrophy and persistent neuropathic pain affecting 10%-25% of cases. Excessive inflammation and immune cell infiltration in the injured nerve hinder axon regeneration and functional recovery. Although adipose-derived stem cells (ASCs) have demonstrated neural regeneration and immunomodulatory potential, their specific effects on compressive neuropathy are still unclear. Methods: We conducted modified CCI models on adult male Sprague-Dawley rats to induce irreversible neuropathic pain and muscle atrophy in the sciatic nerve. Intraneural ASC injection and nerve decompression were performed. Behavioral analysis, muscle examination, electrophysiological evaluation, and immunofluorescent examination of the injured nerve and associated DRG were conducted to explore axon regeneration, neuroinflammation, and the modulation of inflammatory gene expression. Transplanted ASCs were tracked to investigate potential beneficial mechanisms on the local nerve and DRG. Results: Persistent neuropathic pain was induced by chronic constriction of the rat sciatic nerve. Local ASC treatment has demonstrated robust beneficial outcomes, including the alleviation of mechanical allodynia, improvement of gait, regeneration of muscle fibers, and electrophysiological recovery. In addition, locally transplanted ASCs facilitated axon remyelination, alleviated neuroinflammation, and reduced inflammatory cell infiltration of the injured nerve and associated dorsal root ganglion (DRG). Trafficking of the transplanted ASC preserved viability and phenotype less than 7 days but contributed to robust immunomodulatory regulation of inflammatory gene expression in both the injured nerve and DRG. Discussion: Locally transplanted ASC on compressed nerve improve sensory and motor recoveries from irreversible chronic constriction injury of rat sciatic nerve via alleviation of both local and remote neuroinflammation, suggesting the promising role of adjuvant ASC therapies for clinical compressive neuropathy.

Future Considerations in the Diagnosis and Treatment of Compressive Neuropathies of the Upper Extremity.

Compressive neuropathies of the upper extremity are among the most common conditions seen by hand surgeons. The diagnoses of carpal tunnel syndrome and cubital tunnel syndrome have traditionally been made by a combination of history, physical examination, and electrodiagnostic testing. However, findings can be nonspecific and electrodiagnostic testing is invasive for the patient. The diagnosis of compressive neuropathies continues to evolve as technology advances, and newer diagnostic modalities predominantly focus on preoperative diagnostic imaging with ultrasound and magnetic resonance imaging/neurography. With the advent of cheaper, faster, and less invasive imaging, the future may bring a paradigm shift away from electrophysiology as the gold standard for the preoperative diagnosis of compressive neuropathies. Intraoperative imaging of nerve health is an emerging concept that warrants further investigation, whereas postoperative imaging of nerve recovery with ultrasound and magnetic resonance imaging currently has a limited role because of nonspecific findings and potential for misinterpretation. Advances in surgical treatment of compressive neuropathies appear to center around the use of imaging for less invasive neurolysis techniques and other adjunctive treatments with nerve decompression. The management of failed peripheral nerve decompressions and recurrent compressive neuropathies remains challenging.

Misdiagnosis in Amyotrophic Lateral Sclerosis.

The symptoms of amyotrophic lateral sclerosis (ALS) can mimic those of compressive neuropathies, such as carpal and cubital tunnel syndromes, especially early in a patient's clinical course. We surveyed members of the American Society for Surgery of the Hand and found that 11% of active and retired members have performed nerve decompression surgeries on patients later diagnosed with ALS. Hand surgeons are commonly the first providers to evaluate patients with undiagnosed ALS. As such, it is important to be aware of the history, signs, and symptoms of ALS to provide an accurate diagnosis and prevent unnecessary morbidities, such as nerve decompression surgery, which invariably results in poor outcomes. The major "red flag" symptoms warranting further work-up include weakness without sensory symptoms, profound weakness and atrophy in multiple nerve distributions, progressively bilateral and global symptoms, presence of bulbar symptoms (such as tongue fasciculations and speech/swallowing difficulties), and, if surgery is performed, failure to improve. If any of these red flags are present, we recommend neurodiagnostic testing and prompt referral to a neurologist for further work-up and treatment.

A Giant Atypical Baker's Cyst Causing Compressive Neuropathy of Combined Peroneal and Tibial Nerves - A Case Report.

Introduction: Popliteal cysts (Baker cysts) causing compressive neuropathy of combined tibial and common peroneal nerves is an exceptional entity. Especially, an isolated multi-septate unruptured cyst (usually posteromedially) dissecting posterolaterally, thereby causing compression of multiple components of the popliteal neurovascular bundle as seen in this case report is unique in clinical field and in the literature. Awareness and early diagnosis of such cases along with a prudent technique will preclude permanent impairment. Case Report: A 60-year-old man with a 5-year history of a symptomless popliteal mass in his right knee was hospitalized with aberrant gait and walking difficulty that had deteriorated during a 2-month period. The patient reported hypoesthesia across the sensory innervations of tibial and common peroneal nerves. Clinical examination indicated a prominent painless and unfixed cystic, fluctuant swelling extending around 10 × 7 cm in the popliteal fossa encroaching into the thigh. Motor examination showed decrease in the power of ankle dorsiflexion, plantar flexion as well as inversion and eversion of the foot resulted in progressive difficulty in walking with high stepping gait. The action potential amplitudes of the right peroneal and tibial compound muscles were dramatically decreased with a drop in motor conduction velocities and a prolonging of the F-response latencies, according to nerve conduction studies. Magnetic resonance imaging of the knee showed a multi septate popliteal cyst measuring 13.8*6.5*6.8 cm along the medial head of gastrocnemius, and the T2-weighted sagittal and axial sections revealed the cyst connecting with the right knee. He was planned and undergone open cyst excision with decompression of the peroneal and tibial nerves. Conclusion: This exceptional case establishes that Baker's cyst very rarely can cause compressive neuropathy vandalizing both the common peroneal and tibial nerves. Excision of the cyst by open technique along with neurolysis may be a more judicious and successful strategy for resolving symptoms quickly as well as to prevent permanent impairment.

Possible Points of Ulnar Nerve Entrapment in the Arm and Forearm: An Ultrasound, Anatomical, and Histological Study.

BACKGROUND: Ulnar nerve entrapment is one of the most common entrapment neuropathies, usually occurring in the cubital tunnel of the elbow and in Guyon's canal of the wrist. However, it can also occur at other anatomical locations. PURPOSE: Our aim was to review other possible locations of ulnar nerve entrapment in an ultrasound and anatomical study. MATERIAL AND METHODS: Eleven upper limbs from eight adult corpses were ultrasonographically examined and subsequently dissected in a dissection laboratory. Four specific anatomical points were analysed, and any anatomical variations were documented. Moreover, six samples of the nerve were taken for histological analysis. RESULTS: Distinct anatomical relationships were observed during ultrasound and dissection between the ulnar nerve and the medial intermuscular septum, the triceps aponeurosis, Osborne's fascia at the elbow, the arcuate ligament of Osborne and the intermuscular aponeurosis between the flexor carpi ulnaris and the flexor digitorum superficialis muscles. A statistical study showed that these locations are potential areas for ulnar nerve compression. In addition, a fourth head of the triceps brachii muscle was found in some specimens. CONCLUSION: Results demonstrate that ultrasound is a good tool to investigate ulnar nerve entrapment neuropathy and to identify other anatomical points where the nerve can remain compressed.

Cubital tunnel syndrome of the ulnar nerve caused by an epineural ganglion cyst: a case report and review of the literature.

BACKGROUND: The ulnar nerve has a long and complex anatomical course, originating from the brachial neural plexus in the neck with nerve trunk formation at the posterior neck triangle, and on to the axilla. This intricate anatomical pathway renders the nerve susceptible to compression, direct injury, and traction throughout its course. Compression of the ulnar nerve is the second most common compression neuropathy of the median nerve adjacent to the wrist joint, after carpal tunnel syndrome. CASE PRESENTATION: A 45-year-old Sudanese housewife complained of progressive right forearm and hand muscle wasting, pain, and neuropathic symptoms. She was diagnosed with right-sided cubital tunnel syndrome. The diagnosis was derived intraoperatively from a nerve conduction study suggesting the level of conduction block and recommending decompression. Magnetic resonance imaging was not done preoperatively due to financial limitations. An epineural ganglion (15 × 20 mm2) compressing and flattening the ulnar nerve was diagnosed intraoperatively. Surgical decompression of the ulnar nerve and removal of the epineural ganglion achieved a remarkable postoperative result and pleasing outcome. CONCLUSION: Surgical management is the cornerstone of treatment for compressive neuropathy and ranges from simple nerve decompression to complex neurolysis procedures and nerve transposition to adjust the anatomical course of the nerve.

A Sciatic Neuralgia Case of an Entrapment Neuropathy Mimicking Piriformis Syndrome Due to Soft Tissue Hemangioma.

BACKGROUND: Lumbosacral pain is commonly seen in daily clinical practice. In fact, entrapment of the part of the sciatic nerve after the sacral foramen causes some of these pains, which should not be overlooked. The sciatic nerve may be compressed during its course after the sacral foramen for a variety of reasons. We aimed in this article to review extra-spinal compressive sciatic neuropathy reasons and abnormal magnetic resonance imaging (MRI) by presenting a sciatic neuralgia case of an entrapment neuropathy mimicking piriformis syndrome due to soft tissue hemangioma. CASE PRESENTATION: A 30-year-old male patient was admitted with complaints of lumbosacral pain spreading to the leg that had been worsening over the previous 10 days. With the preliminary diagnosis of labral damage and piriformis syndrome, the patient was referred to the radiology clinic for a hip MRI. In the hip MR images, a mass lesion suggestive of heterogeneously enhanced soft tissue hemangioma after the injection of paramagnetic contrast material was observed in the proximal left thigh. The soft tissue hemangioma extends towards the obturator foramen and compresses the sciatic nerve proximal to the femur after the sciatic foramen. CONCLUSION: The diagnosis of lower extremity entrapment neuropathy is frequently misdiagnosed. In these cases, MRI becomes more important for accurate diagnosis. The radiologists' knowledge of the sciatic nerve in MRI, regional anatomy during the course of the sciatic nerve, and abnormal nerve imaging findings will aid in the diagnosis.

Compression of Ulnar Nerve by Ganglion Cyst in Guyon's Canal-a Case Report.

Background: Compression of the ulnar nerve at the level of Guyon's canal is a very rare compressive neuropathy. Due to the vast range of symptoms that can manifest depending on the degree of ulnar nerve compression, the clinical picture is not consistent. Objective: The aim of the study is to outline the diagnostic techniques and therapeutic options. Case report: We reported a case of ganglion cyst-induced compression of the ulnar nerve in Guyon's canal. A 45-year-old female patient underwent surgical ulnar nerve release in Guyon's canal at the Clinic for Plastic and Reconstructive Surgery. Discussion: After a thorough medical history and physical examination, the diagnosis of the syndrome is made, and ultrasound and magnetic resonance imaging (MRI) testing are used to determine the origin of the neuropathy. A ganglion cyst was identified pathohistological one month following the surgical excision of the soft tissue tumor. In order to hasten the patient's nerve recovery, physical therapy was recommended, and the patient was monitored for the following two years. After two years of treatment, the patient has made a very good recovery of the functionally damaged hand, as determined by a modified Bishop scoring method for evaluating functional ulnar nerve recovery. Conclusion: In virtually all cases, early surgical intervention can lead to an outstanding functional recovery. If the symptoms are more severe and continue or get worse for more than three months, early surgical intervention is the gold standard for treating Guyon's canal syndrome. If soft tissue formations are compressing the ulnar nerve in Guyon's canal, MRI is thought to be the gold standard for diagnosis.

Usefulness of critical flicker fusion frequency measurement and its laterality for evaluating compressive optic neuropathy due to pituitary neuroendocrine tumors.

Critical flicker fusion frequency (CFF) is a short but sensitive method for evaluating optic nerve function. We measured CFF in patients with pituitary neuroendocrine tumors (Pit-NETs) to assess its usefulness. Data from 184 patients with nonfunctioning Pit-NETs, who had been treated with transsphenoidal surgery and had no medical history of eye diseases, was used in this retrospective study. Visual acuity decline (VAD) was defined as > 0.10 reduction in logMAR visual acuity and CFF decline (CFD) was defined as CFF value < 35 Hz. Visual field defect (VFD) was evaluated by automated perimetry on a Humphrey visual field analyzer. Potential associations between abnormal test results and tumor height from the suprasellar were analyzed. Contact between the optic nerve or chiasma and the tumor was present and absent in 161 and 23 patients, respectively. In patients showing contact, the difference in CFF between the left and right eyes was larger (p = 0.0008), and the optimal cutoff value using the receiver operating characteristic curve was 3 Hz. Therefore, ≥ 3 Hz was considered positive for CFF laterality (CFL), the most prevalent condition. Tumor height was lower in patients with CFL positivity compared to those with VAD or VFD (p < 0.01). The prevalence of test abnormalities was the highest for small tumors compared to those of other tests. Changes in CFL permit early detection of Pit-NETs. Our results indicate that CFF laterality can be seen in the early stages of compressive optic neuropathy due to Pit-NET.

Anterior Scalene Muscle Block Response Predicts Outcomes Following Thoracic Outlet Decompression.

BACKGROUND: There is no definitive objective measure for diagnosis of thoracic outlet syndrome (TOS), and functional capacity testing on standardized rehabilitation exercises before and after an anterior scalene muscle block (ASMB) has the potential to serve as a predictor of response to surgery and to improve diagnostic accuracy in these cases. METHODS: Patients evaluated for TOS underwent ASMB as a diagnostic test and were retrospectively reviewed. Functional capacity scores were recorded for patients performing repetitive motion exercises immediately before ASMB, 15 minutes after ASMB, and at a minimum of 6 weeks after thoracic outlet decompression (TOD). The primary outcome of interest was correlation between the pre- to post-ASMB difference and the pre-ASMB to postoperative difference with respect to 3 functional work capacity scores. RESULTS: The average change in time-to-fatigue and work product between pre- and post-ASMB of all exercises was an increase of 39.5% and 53.8%, respectively. The greatest pre-ASMB to post-TOD difference was seen for the Extremity Abduction Stress Test with an average improvement of 109.7% and 150.4% for time-to-fatigue and work product, respectively. The degree of percent improvement post-ASMB correlated positively with the degree of percent improvement post-TOD for all exercises with respect to work product and time-to-fatigue. CONCLUSIONS: Patient response to ASMB as measured by functional capacity on rehabilitation exercises predicted objective functional outcomes following TOD. Post-ASMB outcomes correlated with post-TOD outcomes. The ASMB can be used to assist in diagnosing TOS and provide a surrogate for expectation in patients considering undergoing neurogenic TOD.

Open Sciatic Nerve Decompression for Compartment Syndrome after Prolonged Lithotomy Position: A Case Report.

Background: Position-related compressive nerve injury is a frequently reported complication of the lithotomy position. In contrast, compartment syndrome-induced neuropathy after lithotomy with prolonged surgery is rare and prone to misdiagnosis. This case describes the successful open decompression of sciatic neuropathy due to compartment syndrome after a prolonged lithotomy position. Case presentation: A 56-year-old male patient complained of an abnormal sensation in the lower leg and difficulty in dorsiflexion and plantarflexion of the left foot and toes after laparoscopic anterior hepatic sectionectomy for 16 h in a lithotomy position. Physical examination revealed severe pain and paresthesia below the distal left thigh. In manual muscle test grading, dorsiflexion and plantarflexion of the left ankle and toes were classified as grade 1. Computed tomography and magnetic resonance imaging showed ischemic changes in the mid-thigh posterior muscles, and the sciatic nerve was severely swollen at the distal thigh, which was compressed by the proximal edge of the well-leg holder. After debridement of the necrotic tissue and decompression of the sciatic nerve, the pain subsided immediately, and the ankle and toe dorsiflexion motor function improved to grade 4. Conclusions: Most case reports of compressive neuropathy associated with the lithotomy position have been related to conservative treatment. However, if a lesion compressing the nerve is confirmed in an imaging study and the correlation with the patient's symptoms is evident, early surgical intervention can be an effective treatment method to minimize neurological deficits.