Nerve capping treatment using a bioabsorbable nerve conduit with open or closed end for rat sciatic neuroma.

BACKGROUND AND AIMS: Nerve capping treatment using bioabsorbable nerve conduits has recently been introduced for painful amputation neuroma. However, no clinical or experimental data are available for comparing nerve conduits with open distal ends and closed distal ends. Here, we investigated the nerve conduit with open or closed distal ends as the superior capping device, using a commercially available polyglycolic acid (PGA) nerve conduit in a rat sciatic nerve amputation model. METHODS: Ninety-one rats were assigned to three groups: no-capping (n = 30), capping the resected nerve stump with open ends (n = 31), and closed-end nerve conduits (n = 30). Twelve weeks after sciatic neurectomy, with or without capping, the evaluation of neuropathic pain using the autotomy score was performed. Stump neuromas with perineural scars and neuroinflammation were evaluated histologically. RESULTS: The mean autotomy scores in the closed-end nerve conduit group were significantly lower than those in the no-capping group. However, the difference between the open-end nerve conduit and the closed-end nerve conduit groups was insignificant. Histologically, distal axonal fibers expanded radially and formed neuromas in the no-capping group while they were terminated within the PGA conduit in both capping groups. In particular, the closed-end version of the PGA nerve conduit blocked scarring from intruding through the open end and protected the nerve stump with less neuroinflammation. Nerve capping with the closed-end version of the PGA nerve conduit most effectively suppressed perineural neuroinflammation and scar formation around the resected nerve stump. INTERPRETATION: Nerve capping with the PGA nerve conduit, particularly those with closed ends, after rat sciatic neurectomy prevented amputation neuroma and relieved neuropathic pain.

C-Fiber Loss as a Possible Cause of Neuropathic Pain in Schwannomatosis.

Schwannomatosis is the third form of neurofibromatosis and characterized by the occurrence of multiple schwannomas. The most prominent symptom is chronic pain. We aimed to test whether pain in schwannomatosis might be caused by small-fiber neuropathy. Twenty patients with schwannomatosis underwent neurological examination and nerve conduction studies. Levels of pain perception as well as anxiety and depression were assessed by established questionnaires. Quantitative sensory testing (QST) and laser-evoked potentials (LEP) were performed on patients and controls. Whole-body magnetic resonance imaging (wbMRI) and magnetic resonance neurography (MRN) were performed to quantify tumors and fascicular nerve lesions; skin biopsies were performed to determine intra-epidermal nerve fiber density (IENFD). All patients suffered from chronic pain without further neurological deficits. The questionnaires indicated neuropathic symptoms with significant impact on quality of life. Peripheral nerve tumors were detected in all patients by wbMRI. MRN showed additional multiple fascicular nerve lesions in 16/18 patients. LEP showed significant faster latencies compared to normal controls. Finally, IENFD was significantly reduced in 13/14 patients. Our study therefore indicates the presence of small-fiber neuropathy, predominantly of unmyelinated C-fibers. Fascicular nerve lesions are characteristic disease features that are associated with faster LEP latencies and decreased IENFD. Together these methods may facilitate differential diagnosis of schwannomatosis.

Neuroma of the Infrapatellar branch of the saphenous nerve following Total knee Arthroplasty: a case report.

BACKGROUND: Injury to the infrapatellar branch of the saphenous nerve (IBSN) is common during total knee arthroplasty (TKA) with a standard midline skin incision. Occasionally, painful neuromas form at the transection of nerve and cause pain and limitation of the range of motion of the knee joint. CASE PRESENTATION: A 70-year-old woman experienced right knee pain and stiffness for 4 years after TKA. Physical assessment revealed medial tenderness; Tinel's sign was positive. Radiographs revealed that the prosthesis was well-placed and well-fixed. She was diagnosed with arthrofibrosis and possible neuroma after TKA. She underwent right knee exploration, neurectomy, adhesiolysis and spacer exchange. The neuroma-like tissue was sent for pathological examination. The patient recovered uneventfully and at 3-month follow-up reported no recurrence of pain or stiffness. The pathological report confirmed the diagnosis of neuroma. CONCLUSIONS: IBSN injury should be a concern if surgeons encounter a patient who has pain and stiffness after TKA. Tinel's sign, local anesthetic injection, MRI and ultrasound could help the diagnosis and identify the precise location of neuroma. Surgical intervention should be performed if necessary.

Pediatric peripheral nerve tumors: clinical and surgical aspects.

PURPOSE: Pediatric peripheral nerve tumors (PNTs) are rare. Most are related to neurofibromatosis type 1 (NF1) with the potential for malignancy. An ongoing debate occurs about the best approach to such patients. This study describes a cohort of pediatric patients with PNTs and discusses clinical characteristics and surgical treatment. METHODS: We retrospectively reviewed the charts of seven pediatric patients with eight PNTs surgically treated from 2007 to 2018. Information concerning patient demographics, clinical presentation, PNTs characteristics, treatment choice, and outcome were recorded. RESULTS: All children presented with intense pain and a palpable mass. Three of the eight tumors were associated with a neurological deficit. Among the four patients with NF1, two had a neurofibroma and two a malignant peripheral nerve sheath tumor (MPNST). Histologically, three of the lesions were a benign peripheral nerve sheath tumor (BPNST), three a MPNST, and one each a desmoid tumor and Ewing's sarcoma. Two of the eight tumors underwent partial tumor excision and six gross total excisions. CONCLUSIONS: Intense pain at rest, day, and/or night, preventing normal activities; a palpable, hard, immobile mass; an intense Tinel's sign related to the lump; clinical evidence of NF1; and high-speed growth of a tumor in the trajectory of the nerve or plexus should alert the clinician to the potential for malignancy. Preoperative biopsy is not indicated when clinical and imaging findings suggest a benign tumor. The surgical management of PNTs must be to achieve total resection, including wide margins with malignant tumors, though this is not always possible.

Traumatic neuroma of the posterior tibial nerve due to previous surgery presenting as a massive tumor in the midfoot: A case report.

A case report of traumatic neuroma, a benign non-neoplastic tumor of the posterior tibial nerve is presented. The soft tissue mass in the midfoot region was likely a sequela of previous nerve decompression surgery that the patient underwent five years previously in the same region and on the same nerve. Physical examination and history taking, along with an MRI, were important steps in reaching a definitive diagnosis of traumatic neuroma based on the findings of an interventional radiologist and histopathological evaluation of the biopsy by a pathologist. The lesion was subsequently surgically removed utilizing a multidisciplinary management approach. The patient recovered uneventfully and no symptom recurrence was noted at the 30-month follow-up. The tumor was the largest reported in the literature at the time. This case was also unique in that the patient was relieved of pronation and regained tactile sensation in the midfoot.

Ultrasound imaging of brachial plexus trauma in gunshot injury.

INTRODUCTION: Brachial plexus trauma related to gunshot (GS) injury requires early examination and characterization to ensure appropriate treatment. Magnetic resonance imaging (MRI) may be contraindicated when there are metal fragments in a patient's body. Ultrasound (US) may present an alternative to imaging GS-related brachial plexus injury. METHODS: Three patients with GS-related brachial plexus injury who underwent US imaging evaluation at our institution were identified. A retrospective review of the patients' medical records was performed. RESULTS: US characterization of nerve abnormalities after GS injury to the brachial plexus was in agreement with electrodiagnostic and intraoperative findings. DISCUSSION: Information from the US reports was useful in preparation for brachial plexus reconstruction surgery. As such, US has unique utility when MRI cannot be performed. US imaging can provide useful characterization of the brachial plexus after GS injury when performed by an experienced operator. Muscle Nerve 59:707-711, 2019.

A quintessential syndrome with a rare marvelling aetiology: Rosai-Dorfman disease presenting as Conus-Cauda syndrome.

A 19-year-old woman presented with a history of severe lower backache and asymmetric proximal lower limb weakness during the past 3 months. In addition, she also suffered from lower motor neuron-type bladder and bowel symptoms. On examination, paraparesis was noted. Further, sensory examination suggested patchy asymmetric sensory loss in both lower limbs with saddle anaesthesia and areflexia. A clinical diagnosis of Conus-Cauda syndrome was made and contrast-enhanced MRI of the lumbar and sacral spine was done, which confirmed the presence of a mass lesion within the spinal canal involving the cauda equina extending up to the sacral level. She underwent partial resection of the lesion following which the neurological deficits and lower backache resolved. Histopathological evaluation and immunohistochemical analyses uncovered Rosai-Dorfman disease. There was no evidence of disease elsewhere in the body. Since the patient improved significantly following surgery and exhibited no further neurological worsening, she remains under close follow-up.

Traumatic neuroma of the superficial peroneal nerve in a patient: a case report and review of the literature.

BACKGROUND: Traumatic neuromas are rare benign tumors, which are common in trauma or post-operation and accompanied with obvious symptoms of pain. This study will show the superficial peroneal nerve neuroma occurring after resection of hemangioma. CASE PRESENTATION: A 44-year-old male had an operation of the right leg cavernous hemangioma resection in 1995. Half a year after the operation, pain around the wound appeared and gradually aggravated. The patient had the lesion exploration resection in 2013, and the pathological result showed traumatic neuroma. Within half a year of the second operation, severe pain showed up again, so neuroma resection proceeded in May 2015. The postoperative pathological and immunohistochemical results showed traumatic neuroma. According to the postoperative follow-up, there were no symptoms of pain appearing again. LITERATURE REVIEW: The pain is obvious, and B ultrasonography is the most efficient way to find neuromas. Both conservative and operative therapy have their advantages and disadvantages. CONCLUSIONS: There remain many unanswered questions in relation to the treatment of traumatic neuromas, and further research is required, although we have already had adequate understanding of traumatic neuromas.

The Diagnosis and Treatment of Joplin's Neuroma.

Joplin's neuroma is a rare perineurial fibrosis of the medial plantar digital proper nerve arising from various etiologies but most commonly after bunion surgery. Treatment for this painful great toe problem remains controversial. It is our purpose to describe our experience with this chronic pain problem, considering it to be a neuroma requiring resection. A retrospective medical record review of 8 patients with medial hallux pain related to the digital nerve was performed. Each patient had failed to respond to >6 months of nonoperative therapy. At surgery, the medial digital nerve to the hallux was identified distally, the neuroma was resected distally, and the proximal end of the nerve was implanted into the arch of the foot in 7 (87.5%) of the 8 patients. At a mean follow-up of 25 (range 13 to 43) months, 6 results (75%) were excellent, 1 (12.5%) was good, and 1 (12.5%) was fair. The 1 fair result was in the only patient in whom the distal end of the divided nerve was not implanted proximally, according to the patient's request. In conclusion, surgical resection of the medial plantar nerve to the hallux with implantation of the proximal end of the nerve into the arch of the foot, can be expected to result in good to excellent relief of pain in 80% of the patients.

Posttraumatic saphenous neuroma after open tibial fracture.

Neuralgia and neuroma secondary to iatrogenic saphenous nerve injury have been described in the setting of orthopedic surgical interventions. However, postoperative neuropathic pain caused by saphenous neuroma in the setting of orthopedic trauma has not been reported. We present a case of a 43-year-old woman with a symptomatic saphenous neuroma after an open, laterally angulated tibial fracture. The diagnosis was confirmed in the clinical setting, and treatment consisted of neurolysis and partial neurectomy, resulting in complete pain relief and functional recovery. This case demonstrates the diagnosis and treatment strategy for a symptomatic posttraumatic saphenous neuroma in the setting of a healed, open distal one-third tibial fracture.

Chemically Induced Oncogenesis in the Peripheral Nervous System Is Suppressed in Congenic BDIX.BDIV-Mss1 and -Mss7 Rats.

Human malignant peripheral nerve sheath tumors (MPNSTs) are highly aggressive soft-tissue sarcomas with a poor prognosis that arise either in the context of neurofibromatosis 1 or sporadically. Inbred BDIX and BDIV rat strains highly susceptible and resistant, respectively, to the development of ethylnitrosourea-induced MPNST enable us to identify, by using methods not applicable in humans, variant alleles involved in the pathways underlying individual MPNST risk. On the basis of a genome-wide association analysis using reciprocal intercrosses of BDIX and BDIV, BDIV alleles of two loci on chromosome 10, Mss1 and Mss7, were predicted to lower the risk of MPNST, the latter locus with a female bias. In this study we confirm the two nonoverlapping loci by exposing two congenic strains, BDIX.BDIV-Mss1 (Mss1) and BDIX.BDIV-Mss7 (Mss7), each carrying a BDIV genomic segment spanning the respective locus, to ethylnitrosourea. Compared with BDIX rats, the rate of MPNST is reduced 6.2-fold and 2.0-fold for Mss1 and Mss7 rats of both sexes, respectively. Although a moderate gain of survival time (30-50 days) is seen in Mss1 rats of both sexes and Mss7 males, Mss7 females survive 134 days longer than BDIX females. BDIV alleles at Mss7 obviously cause a markedly increased intrastrain sex difference regarding survival time in Mss7 compared with BDIX rats. Fine mapping will lead to the identification of allelic variants modulating rat MPNST risk and subsequently to their human counterparts. This is of particular relevance, because so far neither gene nor anonymous sequence variants have been identified that influence the risk of human sporadic Schwann cell malignancy.

Post-traumatic neuroma due to closed nerve injury. Is recovery after peripheral nerve trauma related to ultrasonographic neuroma size?

OBJECTIVE: traumatic neuroma is a pathological condition of peripheral nervous system consisting of localized proliferation of injured nerve elements. The symptoms depend on the type of involved nerve (motor and/or sensitive) and on the site and the extension of the lesion. Ultrasound is the best tool to depict the morphology of nerve, especially in traumatic conditions. We present a study aimed to assess the correlation between the degree of nerve function and the ultrasound morphology of neuromas. PATIENTS AND METHODS: we retrospectively evaluated 18 patients with neuromas (not transected) occurred after a closed nerve trauma evaluated with clinical and ultrasound assessment. The clinical evaluation was related to the % of increase of cross sectional area as detected by nerve ultrasound respect to normal nerve. RESULTS: we observed that dimensions of neuromas are not related to function until neuroma have cross sectional area 5 times enlarged respect to normal nerve, in this case recovery never occurs. CONCLUSION: our study failed to clear detect a relation between cross sectional area enlargement of neuroma and nerve function, but showed a cut off beyond which prognosis is negative. This result provide some useful information for prognosis, nevertheless we believe that future perspective studies are needed to better understand the timing of developing neuromas and its evolution.

Agricultural crop density and risk of childhood cancer in the midwestern United States: an ecologic study.

BACKGROUND: There is limited evidence for an association between agricultural pesticide exposure and certain types of childhood cancers. Numerous studies have evaluated exposure to pesticides and childhood cancer and found positive associations. However, few studies have examined the density of agricultural land use as a surrogate for residential exposure to agricultural pesticides and results are mixed. We examined the association of county level agricultural land use and the incidence of specific childhood cancers. METHODS: We linked county-level agricultural census data (2002 and 2007) and cancer incidence data for children ages 0-4 diagnosed between 2004 and 2008 from cancer registries in six Midwestern states. Crop density (percent of county area that was harvested) was estimated for total agricultural land, barley, dry beans, corn, hay, oats, sorghum, soybeans, sugar beets, and wheat. Rate ratios and 95% confidence intervals were estimated using generalized estimating equation Poisson regression models and were adjusted for race, sex, year of diagnosis, median household income, education, and population density. RESULTS: We found statistically significant exposure-response relationships for dry beans and total leukemias (RR per 1% increase in crop density = 1.09, 95% CI = 1.03-1.14) and acute lymphoid leukemias (ALL) (RR = 1.10, 95% CI = 1.04-1.16); oats and acute myeloid leukemias (AML) (RR = 2.03, 95% CI = 1.25, 3.28); and sugar beets and total leukemias (RR = 1.11, 95% CI = 1.04, 1.19) and ALL (RR = 1.11, 95% CI = 1.02, 1.21). State-level analyses revealed some additional positive associations for total leukemia and CNS tumors and differences among states for several crop density-cancer associations. However, some of these analyses were limited by low crop prevalence and low cancer incidence. CONCLUSIONS: Publicly available data sources not originally intended to be used for health research can be useful for generating hypotheses about environmental exposures and health outcomes. The associations observed in this study need to be confirmed by analytic epidemiologic studies using individual level exposure data and accounting for potential confounders that could not be taken into account in this ecologic study.

Subcutaneous rupture of the superficial branch of the radial nerve at the wrist. A case report and review of literature.

Isolated neuropathy of the superficial branch of the radial nerve (SBRN) is a rarely recognized pathology. It was initially described by Wartenberg in 1932. Various causes have been published. We report a case of an unusual injury of the SBRN at the wrist, never been previously reported in the literature. A 40-year-old woman presented with pain and paresthesia over the area of the lateral aspect of the wrist, thumb and first web two months after a blunt trauma of the left forearm. After failure of conservative treatment, surgical exploration found a neuroma of one branch of the SBRN. No distal nerve stump was found. Neuroma resection was performed and the nerve was transposed and embedded into the flexor pollicis longus muscle. With a six months follow-up, the result was satisfactory.

A systematic review of ultrasound-guided and non-ultrasound-guided therapeutic injections to treat Morton's neuroma.

BACKGROUND: Morton's neuroma is a frequently painful condition of the forefoot, causing patients to seek medical care to alleviate symptoms. A plethora of therapeutic options is available, some of which include injection therapies. Researchers have investigated injection therapy for Morton's neuroma, and latterly the evidence base has been augmented with methods that use diagnostic ultrasound as a vehicle to deliver the injectate under image guidance for additional accuracy. To date, there seems to be no consensus that ultrasound-guided injections provide better therapeutic outcomes than nonguided injections for the treatment of Morton's neuroma. METHODS: A systematic review was chosen because this method can undertake such a process. The review process identified 13 key papers using predetermined inclusion and exclusion criteria, which then underwent methodological quality assessment using a pretested Quality Index. A narrative synthesis of the review findings is presented in light of the heterogeneity of the data from the extraction process. RESULTS: This systematic review provides an argument that ultrasound guidance can produce better short- and long-term pain relief for corticosteroid injections, can reduce the need for additional procedures in a series of sclerosing alcohol injections, can reduce the surgical referral rate, and can add efficacy to a single injection. CONCLUSIONS: Ultrasound guidance should be considered for injection therapy in the management of Morton's neuroma.