A 57-year-old female presented with a history of a progressively enlarging palmar mass over three years, with associated numbness over the median nerve distribution and difficulty in gripping due to dimensions of the mass. Physical examination revealed a 4 x 5 cm, movable, non-tender mass over the thenar eminence and a 2 x 1 cm movable, non-tender mass over the center of the palm. Tinel’s sign was positive over the mass and the carpal tunnel.

Excision of the mass was performed under intravenous regional anesthesia. A curvilinear incision made from the thenar crease distally to the midline of the wrist overlying the carpal tunnel, proximally. Dissection was carried down to the transverse carpal ligament which was transected to allow visualization of the mass and its attachment to the median nerve.

The mass described in this present case report shares characteristics from cases in previously published literature. Its gross appearance was highly indicative of a lipoma and its close relationship with the median nerve suggested an epineural origin. Magnetic resonance imaging revealed a well-defined lesion, suggesting a mass that was more likely to be excised, potentially leading to better neurologic outcomes.

Intraneural lipomas (within the epineurium) are rare soft-tissue tumors that predominantly occur in the hand and forearm. Most cases reported involve the median nerve, followed by the radial nerve, posterior interosseus nerve and more rarely the brachial plexus. Compression of peripheral nerves by benign adipose tumors is infrequently reported in literature, with most publications restricted to case reports or series of a few patients. To the author’s knowledge, this is the first article describing an intraneural lipoma in the Filipino population.

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive lethal malignancy, characterized by late diagnosis, aggressive growth, and therapy resistance, leading to a poor overall prognosis. Emerging evidence shows that the peripheral nerve is an important non-tumor component in the tumor microenvironment that regulates tumor growth and immune escape. The crosstalk between the neuronal system and PDAC has become a hot research topic that may provide novel mechanisms underlying tumor progression and further uncover promising therapeutic targets. In this review, we highlight the mechanisms of perineural invasion and the role of various types of tumor innervation in the progression of PDAC, summarize the potential signaling pathways modulating the neuronal-cancer interaction, and discuss the current and future therapeutic possibilities for this condition.
Humans ; Carcinoma, Pancreatic Ductal/pathology* ; Pancreatic Neoplasms/therapy* ; Signal Transduction ; Peripheral Nerves/metabolism* ; Tumor Microenvironment

Our previous investigation suggested that faster seventh cervical nerve (C7) regeneration occurs in patients with cerebral injury undergoing contralateral C7 transfer. This finding needed further verification, and the mechanism remained largely unknown. Here, Tinel's test revealed faster C7 regeneration in patients with cerebral injury, which was further confirmed in mice by electrophysiological recordings and histological analysis. Furthermore, we identified an altered systemic inflammatory response that led to the transformation of macrophage polarization as a mechanism underlying the increased nerve regeneration in patients with cerebral injury. In mice, we showed that, as a contributing factor, serum amyloid protein A1 (SAA1) promoted C7 regeneration and interfered with macrophage polarization in vivo. Our results indicate that altered inflammation promotes the regenerative capacity of the C7 nerve by altering macrophage behavior. SAA1 may be a therapeutic target to improve the recovery of injured peripheral nerves.
Animals ; Brachial Plexus ; Brachial Plexus Neuropathies/surgery* ; Humans ; Mice ; Nerve Transfer ; Peripheral Nerves ; Spinal Nerves

BACKGROUND: Multifocal motor neuropathy (MMN), Lewis-Sumner syndrome (LSS), and many chronic inflammatory demyelinating polyradiculoneuropathies (CIDPs) are representative of acquired multifocal polyneuropathy and are characterized by conduction block (CB). This retrospective study aimed to investigate the demyelinating distribution and the selective vulnerability of MMN, LSS, and CIDP with CB (CIDP-CB) in nerves. METHODS: Fifteen LSS subjects (107 nerves), 24 MMN subjects (176 nerves), and 17 CIDP-CB subjects (110 nerves) were included. Their clinical information was recorded, blood and cerebrospinal fluid tests were conducted, and nerve conductions of the median, ulnar, radial, peroneal, and tibial nerves were evaluated. CB, temporal dispersion, distal motor latency (DML), and F-wave latency were recorded, and nerve conduction velocity, terminal latency index, and modified F-wave ratio were calculated. RESULTS: CB was more likely to occur around the elbow in CIDP-CB than in MMN (78.6% vs. 6.8%, P < 0.01) but less likely to occur between the wrist and the elbow than in LSS (10.7% vs. 39.3%, P < 0.05). Tibial nerve CB was most frequently observed in MMN (47.4%, P < 0.05). CIDP-CB was characterized by a prolonged DML in all nerves, and slow motor nerve velocity of the upper limb was significant when CB nerves were excluded (P < 0.05). CONCLUSIONS We report the different distributions of segmental and diffuse demyelination of the ulnar and tibial nerves in LSS, MMN, and CIDP-CB. These distinct distributions could help in differentiating among these conditions.
Humans ; Neural Conduction ; Peripheral Nerves ; Polyneuropathies ; Polyradiculoneuropathy, Chronic Inflammatory Demyelinating ; Retrospective Studies

Malignant peripheral nerve sheath tumor (MPNST) is rare, accounting for 5-10% of all soft tissue sarcomas. MPNST is characteristically aggressive and has a poor prognosis. Fifty percent of patients with MPNST have neurofibromatosis type 1 (NF1). NF-associated MPNST occurs more often at younger ages than sporadic MPNST, but the survival difference is controversial. Superficial MPNST from a recurrent neurofibroma is extremely rare and only a limited number of cases have been reported in the literature. Herein, we report an unusual case of superficial MPNST from a recurrent neurofibroma in a patient without NF1.
Abdominal Wall ; Humans ; Nerve Sheath Neoplasms ; Neurilemmoma ; Neurofibroma ; Neurofibromatoses ; Neurofibromatosis 1 ; Neurofibrosarcoma ; Peripheral Nerves ; Prognosis ; Sarcoma

Schwannoma is a slow-growing, well-demarcated, benign soft tissue tumor of the peripheral nerve sheath. It commonly develops in the head and neck region, usually in the parapharyngeal space. In this case, a 42-year-old woman visited the outpatient department to manage a painless mass on her left cheek. She had no history of concern and no neurological symptoms were observed. In the enhanced computed tomography scan, a 2.8 × 2.8 × 1.8 cm, heterogeneously enhanced tumor was detected in the left masseter muscle. A tumor resection under general anesthesia was planned. For the resection, a facelift incision was chosen; branches of the facial nerve were identified and retrogradely dissected. A well-marginated, yellowish, solid mass was found in the left masseter muscle. The mass was excised and given a histopathological diagnosis of schwannoma. A definite diagnosis of schwannoma, originating in the masseter muscle, is difficult to arrive at with radiographic findings alone; it is often misdiagnosed as intramuscular hemangioma. Histopathological examinations, including fine-needle aspiration or histological biopsy after surgery, are necessary. Using a facelift incision with retrograde facial nerve dissection, tumor resection in an intramasseteric lesion can be performed efficiently, without nerve damage, or leaving conspicuous scars on the face.
Adult ; Anesthesia, General ; Biopsy ; Biopsy, Fine-Needle ; Cheek ; Cicatrix ; Diagnosis ; Facial Nerve ; Female ; Head ; Hemangioma ; Humans ; Masseter Muscle ; Neck ; Neurilemmoma ; Outpatients ; Peripheral Nerves ; Rhytidoplasty

Chronic postoperative inguinal pain (CPIP) is a major complication after inguinal herniorrhaphy. We report the treatment of CPIP using ultrasonography-combined with nerve stimulator for injection of the genitofemoral nerve (GFN). A 59-year-old man underwent laparoscopic herniorrhaphy and presented with numbness from the inguinal region to the scrotum after operation. In the pain clinic, ultrasonography-guided GFN block and pharmacological treatments had little effect. Six month after operation, patient was referred to the Department of Physical Medicine and Rehabilitation, and ultrasonography-combined with nerve stimulator for GFN injection underwent to enhance the accuracy of neural approach. The induction of scrotal contraction and paresthesia on the GFN distribution was monitored by nerve stimulator and local anesthetic was injected. After the block, pain relief lasted for 6 months without analgesic use. Ultrasonography-combined with nerve stimulator is an effective approach to treat CPIP as it enhances precise localization and injection of small peripheral nerve like GFN.
Herniorrhaphy ; Humans ; Hypesthesia ; Middle Aged ; Pain Clinics ; Paresthesia ; Peripheral Nerves ; Physical and Rehabilitation Medicine ; Scrotum

The use of ideal pain management modalities after total knee arthroplasty facilitates enhanced recovery by promoting early ambulation and controlling postoperative pain. To achieve these goals, multimodal analgesia, including motor-sparing peripheral nerve blocks, appears to be promising in older adults undergoing total knee arthroplasty. This review describes optimal nerve blocks, as a part of multimodal analgesia for total knee arthroplasty, and the scientific basis of each technique.
Adult ; Analgesia ; Arthroplasty, Replacement, Knee ; Early Ambulation ; Humans ; Nerve Block ; Pain Management ; Pain, Postoperative ; Peripheral Nerves

Schwannoma or neurilemmoma is a benign peripheral nerve sheath tumor that arises from Schwann cells. Approximately 25–45% of all schwannomas occur in the head and neck regions, and the intraoral presentation of these is only 1%. We report a rare case of a patient presenting tongue base schwannoma with characteristic imaging features on computed tomography and magnetic resonance imaging.
Diagnosis, Differential ; Head ; Humans ; Magnetic Resonance Imaging ; Neck ; Nerve Sheath Neoplasms ; Neurilemmoma ; Peripheral Nerves ; Schwann Cells ; Tongue

Electrodiagnostic tests (EDX) is essential for the diagnosis of chronic inflammatory demyelinating polyneuropathy (CIDP). EDX could provide information about demyelinating pathology in the peripheral nerves. According to phenotypes, CIDP could be classified several phenotypes, which has different clinical manifestations, EDX could present a different distribution pattern of demyelinating lesions. In addition, EDX could be useful markers for predicting treatment response of prognosis of CIDP.
Classification ; Diagnosis ; Electrodiagnosis ; Neural Conduction ; Pathology ; Peripheral Nerves ; Phenotype ; Polyneuropathies ; Polyradiculoneuropathy, Chronic Inflammatory Demyelinating ; Prognosis