Tuberculous Flexor Tenosynovitis with Median Nerve Compression: A Case Report.

CASE: A 65-year-old female patient presented with complaints of diffuse pain and swelling in her right wrist with paresthesia in her right hand with thenar wasting. Her magnetic resonance imaging scan was suggestive of flexor tenosynovitis of the wrist with compression of the median nerve with multiple rice bodies. She underwent excisional biopsy along with median nerve decompression. Mycobacterium tuberculosis was detected by polymerase chain reaction (GeneXpert), and histopathology identified caseous granulomas. The patient was started on antitubercular chemotherapy postoperatively. CONCLUSION: In endemic countries such as India, tuberculous flexor tenosynovitis must always be a differential diagnosis in cases of wrist swelling with rice bodies.

Fascicular Involvement of the Median Nerve Trunk in the Upper Arm: Manifestation as Anterior Interosseous Nerve Syndrome With Unique Imaging Features.

Selective fascicular involvement of the median nerve trunk above the elbow leading to anterior interosseous nerve (AIN) syndrome is a rare form of peripheral neuropathy. This condition has recently garnered increased attention within the medical community owing to advancements in imaging techniques and a growing number of reported cases. In this article, we explore the topographical anatomy of the median nerve trunk and the clinical features associated with AIN palsy. Our focus extends to unique manifestations captured through MRI and ultrasonography (US) studies, highlighting noteworthy findings, such as nerve fascicle swelling, incomplete constrictions, hourglass-like constrictions, and torsions, particularly in the posterior/posteromedial region of the median nerve. Surgical observations have further enhanced the understanding of this complex neuropathic condition. High-resolution MRI not only reveals denervation changes in the AIN and median nerve territories but also illuminates these alterations without the presence of compressing structures. The pivotal roles of high-resolution MRI and US in diagnosing this condition and guiding the formulation of an optimal treatment strategy are emphasized.

Giant lipofibromatous hamartoma of median nerve in a child

Lipofibromatous hamartoma (LFH) is a rare fibrofatty tumor of adipocytes within peripheral nerves, affecting mainly children. It typically presents as a palpable mass surrounding the nerves of the upper limbs, causing pain and neurological deficits in the affected nerve distribution. We report the case of a child with a 2-years presentation of a mass in the right wrist associated with pain and paresthesia, who underwent investigation with magnetic resonance imaging (MRI). It showed thickening of the median nerve with spaghetti-like appearance associated with lipomatous tissue in a coaxial cable-like pattern, both features characteristic of LFH. This case illustrates the importance of MRI in the differential diagnosis of limb masses in the pediatric population.

Factors Affecting the Occurrence of Late Median Nerve Neuropathy After Open Reduction and Volar Locking Plate Fixation of Distal Radius Fracture.

It is well-known that late median nerve neuropathy can occur after open reduction and internal fixation (ORIF) of distal radius fracture (DRF). The current study investigated the predictive factors of late median nerve neuropathy after ORIF with a volar locking plate for DRF. The authors retrospectively reviewed 712 patients who underwent ORIF using a volar locking plate after DRF at 3 medical institutions between 2006 and 2017. Thirty-seven (5.2%) patients developed late median nerve neuropathy at a mean of 8.25±3.47 months (range, 3-19 months) after surgery. The radiographic data of 37 patients (group A) who had late median nerve neuropathy were compared with those of 148 patients (group B) who did not. Group A had a significantly higher proportion of type C3 fracture and Soong grade 2 than group B. Postoperative dorsal tilt in group A was greater than that in group B. On multivariable logistic regression analysis, the following predictive factors were associated with late median nerve neuropathy: increased postoperative dorsal tilt and Soong grade 2. The development of late median nerve neuropathy after ORIF using a volar locking plate for DRF was associated with increased postoperative dorsal tilt and the plate being placed distal to the volar rim. Physicians should consider the possibility of late median nerve neuropathy in patients with these factors during follow-up. [Orthopedics. 2021;44(3):e367-e372.].

A Rare Case of Median Nerve Entrapment within the Bone After Surgical Treatment of a Pediatric Supracondylar Humerus Fracture: A Case Report.

CASE: We present the rare event of median nerve bony entrapment after a supracondylar distal humerus fracture in a child. The median nerve was both clinically and electrically still, partially intact at 2 years after the injury. The nerve was surgically extracted from the bone. Follow-up evaluation a year later showed motor and sensory improvement. We found only 2 similar reports in the literature and one similar postmortem example. CONCLUSION: We hope that this case brings awareness of an unusual complication after a commonly encountered injury.

Surgical Excision of a Thrombosed Persistent Median Artery Causing Carpal Tunnel-Like Symptoms: A Case Report.

CASE: A 51-year-old man presented with pain and paresthesias in the median nerve distribution and a subjective loss of grip strength. Imaging revealed a thrombosed persistent median artery in the carpal tunnel abutting the median nerve. The thrombosed portion of the artery was surgically excised, and the patient experienced resolution of symptoms. CONCLUSION: Persistent median artery thrombosis is rare and can cause carpal tunnel syndrome. Ultrasound is a useful tool for diagnosis and appropriate surgical planning. Although treatment with systemic anticoagulation is an option, surgical excision resulted in resolution of symptoms and an excellent short-term outcome.

Role of Ultrasonography in Severe Distal Median Nerve Neuropathy.

PURPOSE: Electrodiagnostic studies do not differentiate severe lesions of the median nerve in the distal forearm from those within the carpal tunnel when compound muscle action potential over the abductor pollicis brevis and sensory nerve action potential are absent; needle electromyography showing denervation confined to the abductor pollicis brevis is presumed to suggest localization to the carpal tunnel, although the lesion may be in the forearm. Under these circumstances, the patient may undergo carpal tunnel release without benefit. This retrospective study looked at patients with clinical picture of severe carpal tunnel syndrome who had no compound muscle action potential or sensory nerve action potential on median nerve stimulation; the goal was to determine how often ultrasonic imaging pointed to a location other than the carpal tunnel. METHODS: Patients with clinical picture of severe carpal tunnel syndrome with no sensory nerve action potential and no compound muscle action potential over the abductor pollicis brevis and second lumbrical underwent ultrasonic imaging; criteria for localization to the carpal tunnel included significant increase in the cross-sectional area of the median nerve at the carpal tunnel inlet and increase in the wrist/forearm cross-sectional area ratio. RESULTS: In 42 of 46 cases, entrapment at the carpal tunnel was confirmed by ultrasonography; in four patients, other causes were located proximal to the carpal tunnel. CONCLUSIONS: Ultrasonic imaging is useful not only for confirming entrapment of the median nerve at the carpal tunnel in patients with nonlocalizing electrodiagnostic studies but also in detecting pathology in the forearm, which may mimic severe carpal tunnel syndrome.

Resonancia magnética en el atrapamiento del nervio supraescapular por quiste supraglenoideo / Magnetic resonance in nerve entrapment suprascapular supraglenoid cyst

El síndrome de atrapamiento del nervio supraescapular es una causa infrecuente de dolor en el hombro y de difícil diagnóstico clínico. Puede ser consecuencia de traumatismo, infección, compresión extrínseca o estiramiento secundario a movimientos repetitivos. Los quistes supraglenoideos deben considerarse en el diagnóstico diferencial pues son una causa frecuente de compresión del nervio supraescapular que ocurre casi exclusivamente en hombres. Se evaluaron con resonancia magnética (RM) y en forma retrospectiva siete pacientes con diagnóstico de atrapamiento del nervio supraescapular por quiste supraglenoideo. La RM mostró la causa y localización de la compresión nerviosa así como la distribución del edema muscular en todos los casos. Puede evaluar el grado de severidad de la enfermedad y realizar el diagnóstico diferencial con otras causas que provocarían atrapamiento del nervio supraescapular. (AU)

Suprascapular nerve entrapment has been regarded as a relatively uncommon condition that is easily overlooked in the differential diagnosis of shoulder discomfort. The common feature is nerve damage, caused either by trauma, extrinsic compression or by stretching secondary to repeated movements. Ganglion cysts account for the majority of the masses causing entrapment and seem to occur exclusively in men. Seven cases of suprascapular nerve entrapment caused by supraglenoid cyst compression were reviewed with MRI. MRI showed the cause and location of nerve compression as well as the distribution of muscular edema in all cases. MR imaging also allows an evaluation of the severity of the disease. It is also very efficient in excluding several differential diagnoses. (AU)

Lipofibromatous hamartoma of the median nerve: 3T MRI evaluation by constrained spherical deconvolution analysis.

In this study we described a case of lipofibromatous hamartoma involving the median nerve. We adopted diffusion tensor imaging and constrained spherical deconvolution-based tractography to reconstruct the affected median nerve. Moreover, we extracted diffusion-based parameters reflecting axonal integrity loss of median nerve fibres. Our data showed that constrained spherical deconvolution-based tractography outperformed the diffusion tensor imaging-based method, allowing the detection of the entire median nerve, including its branches, thus offering a robust method to investigate the involvement of the median nerve in pathological conditions. All clinical and technical implications are extensively described.

Comparison of Different Sequences of Magnetic Resonance Imaging and Ultrasonography with Nerve Conduction Studies in Peripheral Neuropathies.

BACKGROUND: Peripheral neuropathies refer to a group of disorders in which there is damage to the nerves of the peripheral nervous system. Electrophysiologic studies are the main stay for the diagnosis of peripheral neuropathies. However, direct visualization of the nerves is possible with exact localization of site of disease with high-resolution ultrasonography (USG) and 3-Tesla magnetic resonance imaging (MRI) scanner, and newer magnetic resonance (MR) sequences. METHODS: We performed a cross-sectional study including 55 patients and 64 nerves with upper limb peripheral neuropathies. All patients included underwent high-resolution focused USG of the nerves and MR neurography. A nerve conduction velocity study was performed for reference. RESULTS: The diagnostic confidence of the turbo spin echo T2-weighted (T2W) MR sequence was seen to be highest, with a sensitivity of 95.31%, whereas it was 81.25% for USG. Continuity of the nerve in patients with traumatic neuropathy was seen in 65.7% and 62.86% (22/35) nerves on MRI and USG, respectively. T1-weighted and T2W MR sequences were seen to be equally effective in establishing the continuity of the nerve. Increase in the caliber/thickening was seen in 77% of cases on MRI and 73.8% of cases on USG. Neuroma formation was seen equally on both MR and USG in 60.66%. We consistently found low fractional anisotropy (FA) values at the site of disease. CONCLUSIONS: USG is a sensitive technique to diagnose peripheral neuropathies and it should be used as a screening modality for focused MR to be performed later. Turbo spin echo T2W fast spin has the highest sensitivity to identify nerve disease and is comparable with nerve conduction studies. Among the newer sequences, diffusion tensor imaging should be performed to increase diagnostic confidence.

Ultrasonographic findings of proximal median neuropathy: A case series of suspected distal neuralgic amyotrophy.

Spontaneous anterior interosseous nerve (AIN) palsy develops following the resolution of nerve pain, which may be considered as distal neuralgic amyotrophy. NA is assumed to have a complex etiology, but an autoimmune mechanism is likely involved. However, precise assessment of the lesion is challenging. We examined five consecutive patients with suspected spontaneous AIN palsy using ultrasonography. On electromyography, all patients exhibited denervation potentials in the muscles, not only in the AIN territory, but also in the proximal median nerve territory (e.g., the flexor carpi radialis or pronator teres). Ultrasonography of the median nerve demonstrated neural swelling at the proximal side of the medial epicondyle in four patients and an hourglass-like constriction of the nerve fascicle in three patients. Four patients were diagnosed with distal neuralgic amyotrophy; of these, three received intravenous immunoglobulin administration, but only limited beneficial effect was achieved in one patient with early stage disease. One patient showed significant median nerve hypertrophy on ultrasonography and was diagnosed with neurolymphomatosis following the detection of malignant lymphoma during a systemic survey. Our experience demonstrates that ultrasonography for proximal median neuropathy presenting as AIN palsy may be useful for the accurate lesion assessment.

A Comparison of Magnetic Resonance Imaging and Electroneuromyography for Denervated Muscle Diagnosis.

PURPOSE: The aim of this study was to evaluate the diagnostic value of magnetic resonance imaging (MRI) for muscle denervation due to focal lesions of the median nerve and to compare electrophysiological findings with MRI findings. METHODS: Twenty-six patients with electrophysiological studies diagnosed for focal lesions of the median nerve were included in this study. Electrophysiological studies and MRI were conducted on 34 patients' hands. Patients' hands were divided into two groups based on edema findings revealed by the MRI: group 1 (edema-negative group; n = 24) and group 2 (edema-positive group; n = 10). RESULTS: Positive correlations were found between the existence of edema in MRI and fibrillation, positive sharp waves, denervation, and the level of reduced recruitment pattern. In median nerve conduction studies, amplitude of compound muscle action potential and palm-to-wrist segment mixed-nerve action potentials were significantly lower, and also the third-digit wrist sensory nerve conduction velocity and mixed-nerve palm-wrist conduction velocity were significantly slower in group 2. CONCLUSIONS: For muscle denervation resulting from median nerve lesions, MRI findings correlated with electrophysiological findings; further study is required for the use of MRI.

Schwannoma of the median nerve mimicking carpal tunnel syndrome in a pregnant patient. Case report.

In patients with symptoms of a peripheral neuropathy especially during pregnancy, use of imaging techniques such as Ultrasound (US) and Magnetic Resonance Imaging (MRI) may be essential for the diagnostic accomplishment. A 30-weekspregnant diabetic female attending US evaluation due to intermittent hand pain, numbness, and weakness bilaterally. Although, the US evaluation revealed the median nerve (MN) normal size, echogenicity and echo-texture within the right carpal tunnel; the US assessment applied proximally to the carpal tunnel, revealed a hypoechoic tumor-like mass and increased MN cross section area. In transverse view, the MN was detected as an eccentric, hypoechoic structure compressed by the aforementioned mass. A presence of MN schwannoma or neurofibroma was suspected. US has been proved to be extremely useful to determine location, extent as well as the type of nerve lesion.

Successful Treatment of Complex Regional Pain Syndrome with Pseudoaneurysm Excision and Median Nerve Neurolysis.

BACKGROUND: Complex regional pain syndrome (CRPS), formerly referred to as reflex sympathetic dystrophy, is a pain syndrome characterized by severe pain, altered autonomic and motor function, and trophic changes. CRPS is usually associated with soft tissue injury or trauma. It has also been described as a rare complication of arterial access for angiography secondary to pseudoaneurysm formation. CASE DESCRIPTION: A 73-year-old woman underwent catheterization of the left brachial artery for angiography of the celiac artery. The following day, the patient noticed numbness and severe pain in the median nerve distribution of the left upper extremity. Over the next 6 months, the patient developed CRPS in the left hand with pain and signs of autonomic dysfunction. Further work-up revealed the formation of a left brachial artery pseudoaneurysm with impingement on the median nerve. She underwent excision of the pseudoaneurysm with decompression and neurolysis of the left median nerve. Approximately 6 weeks after surgery, the patient had noticed significant improvement in autonomic symptoms. CONCLUSIONS: This case involves a unique presentation of CRPS caused by brachial artery angiography and pseudoaneurysm formation. In addition, the case demonstrates the efficacy of pseudoaneurysm excision and median nerve neurolysis in the treatment of CRPS as a rare complication of arterial angiography.