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.

Neurolymphomatosis: A report of 2 cases representing opposite ends of the clinical spectrum.

INTRODUCTION: Neurolymphomatosis (NL) is a rare disorder characterized by invasion of cranial or peripheral nerves, nerve roots, or plexi, usually by aggressive subtypes of non-Hodgkin lymphoma (NHL). The most common clinical presentation is that of a painful polyneuropathy or polyradiculopathy, followed by cranial neuropathy and, less frequently, by painless polyneuropathy. METHODS: Clinical and pathologic findings are reported for 2 NL cases. RESULTS: The following 2 patients with NL, with disparate clinical presentations, are presented: a patient with subacute onset, painful, multifocal, mixed axonal and demyelinating radiculoplexus neuropathy due to a large B-cell NHL, who required 2 targeted fascicular nerve biopsies to demonstrate NL; and a patient with a slowly progressive, length-dependent axonal polyneuropathy due to a low-grade B-cell lymphoproliferative disorder, as shown on a diagnostic sural nerve biopsy. CONCLUSIONS: The cases described illustrate the wide clinical spectrum of NL.

Advantages of intra-capsular micro-enucleation of schwannoma arising from extremities.

BACKGROUND: Schwannoma is the most common tumor of the peripheral nerves, with surgical enucleation being the established treatment modality. However, some schwannomas cannot be easily enucleated and this sometimes results in iatrogenic nerve injury even with atraumatic procedures. Here we present a retrospective review of the management of schwannoma in the extremities and compare clinical outcomes from the two techniques of extra-capsular and intra-capsular enucleation. METHODS: We reviewed 36 schwannomas from 35 patients who underwent surgical excision of schwannomas arising from the extremities. Twenty had undergone extra-capsular resection and 16 had undergone enucleation using the intra-capsular technique. The post-operative neurological deficits were graded as minor, major, and transient. The duration of symptoms, maximum tumor diameter and site of occurrence were compared between patients with the three grades of deficit. RESULTS: In total, 22 patients developed no sensory changes following enucleation of schwannoma or only temporary and minor changes that had fully resolved within 6 months. Ten patients developed new neurological deficits following surgery that took longer than 6 months to resolve. Four patients experienced new motor deficits or paresthesia following operation that had still not recovered at the final follow-up, all of whom underwent enucleation using the extra-capsular technique. Neurological deficit after enucleation was significantly lower using the intra-capsular compared with the extra-capsular technique. Patient age, duration of symptoms, maximum diameter of the tumor and site of occurrence did not influence the neurological deficit following enucleation of schwannoma. CONCLUSION: These results support intra-capsular micro-enucleation as a safe and reliable treatment for every type of schwannoma. To minimize the risk of nerve injury, en bloc resection should not be used because the main purpose of schwannoma surgery is the relief of symptoms, not tumor resection. Thorough pre-operative counseling of patients to inform them of the potential occurrence of neurological deficit is important.

Assessment of pure single nerve root resection in the treatment of spinal schwannoma: focus on solitary spinal schwannomas located below the thoracolumbar junction.

BACKGROUND: The incidence of neurological deficits is reportedly low after sacrificing the affected nerve root during spinal schwannoma treatment. Although the incidence has been widely reported, the operative method for nerve root resection has been not clarified. To evaluate the safety of pure nerve root resection, we focused on solitary spinal schwannomas below the thoracolumbar level and investigated the effect of affected nerve resection. METHODS: Twenty-three spinal schwannoma patients were retrospectively examined. The mean age at surgery was 53 years. We investigated preoperative symptoms, duration of the disorder, postoperative neurological deficits, and clinical outcomes. In addition, we measured tumor size on computed tomography after myelography or on magnetic resonance images using image-analysis software. We retrospectively assessed correlations among duration of symptoms, tumor size, and postoperative neurological deficits. RESULTS: The tumors comprised 19 intradural schwannomas and 4 dumbbell-shaped schwannomas. No postoperative neurological deficits were observed in the intradural schwannoma patients. In contrast, three of the four dumbbell-shaped schwannoma patients experienced postoperative neurological deficits. Among these three patients, two recovered quickly whereas one never recovered. The mean duration of the disorder was 29 months. The postoperative modified JOA score (13.0) was significantly improved compared with the preoperative score (8.9). The mean maximum tumor sizes were 97.2 mm(2) for the intradural schwannomas and 884.0 mm(2) for the dumbbell-shaped schwannomas. There were no correlations among tumor size, duration of the disorder, and postoperative neurological deficits. CONCLUSIONS: On the basis of this study, we recommend pure single nerve resection for treatment of intradural spinal schwannomas before such tumors progress and involve other normal roots, because postoperative neurological deficits did not occur in our intradural schwannoma patients, irrespective of tumor size, when this procedure was used. However, dumbbell-shaped schwannoma patients should be carefully treated operatively, because high incidence of postoperative neurological deficits can be expected.

Synchronous colonic adenocarcinoma and pelvic schwannoma.

Pelvic schwannomas are rare; it is even more rare for a pelvic schwannoma to occur concurrently with a colon cancer. The authors report the case of a 62-year-old woman with a cecal mass that was surgically removed and the histopathologic diagnosis was adenocarcinoma of the colon. Meanwhile, aretroperitonealpelvic nodalmasswas detected as questionable metastasis of the primary tumor. A subsequent computed tomography-guided fine-needle biopsy was carried out to establish the tumor stage. Surprisingly, the fine-needle biopsy revealed a benign schwannoma. This unusual case posed a dilemma in postoperative staging of the colon cancer.

Effects of vestibular neurectomy and neural compensation on head movements in patients undergoing vestibular schwannoma resection.

The vestibular system is vital for maintaining balance and stabilizing gaze and vestibular damage causes impaired postural and gaze control. Here we examined the effects of vestibular loss and subsequent compensation on head motion kinematics during voluntary behavior. Head movements were measured in vestibular schwannoma patients before, and then 6 weeks and 6 months after surgical tumor removal, requiring sectioning of the involved vestibular nerve (vestibular neurectomy). Head movements were recorded in six dimensions using a small head-mounted sensor while patients performed the Functional Gait Assessment (FGA). Kinematic measures differed between patients (at all three time points) and normal subjects on several challenging FGA tasks, indicating that vestibular damage (caused by the tumor or neurectomy) alters head movements in a manner that is not normalized by central compensation. Kinematics measured at different time points relative to vestibular neurectomy differed substantially between pre-operative and 6-week post-operative states but changed little between 6-week and > 6-month post-operative states, demonstrating that compensation affecting head kinematics is relatively rapid. Our results indicate that quantifying head kinematics during self-generated gait tasks provides valuable information about vestibular damage and compensation, suggesting that early changes in patient head motion strategy may be maladaptive for long-term vestibular compensation.

Cystic Dumbbell-Shaped C1 Schwannoma with Intracranial Extension and Hydrocephalus.

BACKGROUND: Schwannomas at the craniocervical junction commonly originate from the lower cranial nerves or C1 and C2 nerves. To date, very few cases of C1 schwannomas have been described in the literature, and the majority involve either the intra- or the extradural compartment, but not both. To our knowledge, this report documents the first case of a dumbbell-shaped C1 schwannoma that encompassed both intra- and extradural compartments and was accompanied by hydrocephalus. CASE DESCRIPTION: The patient was admitted to our hospital, where magnetic resonance imaging revealed a tumor at the craniocervical junction, extending from the C1 level of the right first cervical vertebra into the cerebellopontine angle with 2 giant cysts. We removed the tumor by performing a midline posterior craniectomy and cervical laminectomy. Intraoperatively, the tumor was found to originate from the right C1 posterior root. The pathological diagnosis was of a schwannoma. The patient was subsequently discharged without any neurologic deficits. CONCLUSIONS: To our knowledge, we present the first case of a dumbbell-shaped C1 schwannoma with intracranial extensions and accompanying hydrocephalus. The tumor had spread inside and outside the dura, but was safely removed. Our findings in this case emphasize that to achieve safe resection, detailed case-specific preoperative consideration is essential.

The outcome of Morton's neurectomy in the treatment of metatarsalgia.

Morton's neuroma is a common cause of metatarsalgia caused by intermetarsal digital nerve thickening. This study reviews the pathology, presentation, symptoms and signs, and patient satisfaction with surgical treatment. Seventy-eight patients (82 feet) were treated for Morton's metatarsalgia by excision of the interdigital nerve. The patients were followed-up for a mean of 4.6 years (range 0.8-8.1 years) and scored using the Foot Functional Index and the American Orthopedic Foot Ankle Society scoring system. In 74 patients the Foot Functional Index was more than 85 (maximum score 100). Seventy-one patients scored more than 90 on the American Orthopedic Foot Ankle Society scoring system with two patients scoring 100 (maximum score). Postoperatively, 82% reported excellent or good results, 10% had a fair result with restriction of activities or pain and 8% had no improvement at all after surgery while 71% had restrictions with footwear.

Structural Origin and Surgical Complications of Peripheral Schwannomas.

BACKGROUND/AIM: In this study, we investigated the locations and surgical complications of schwannomas. PATIENTS AND METHODS: Data of 130 patients with schwannomas were retrospectively reviewed. Pre- and post-operative neurological symptoms, tumor locations, and nerves of origin (sensory, motor, or mixed) were reviewed. RESULTS: Before surgery, 69 patients had Tinel-like signs, 56 patients had pain, 32 patients had numbness, four patients had motor deficits. After surgery, 20 patients had developed a new neurological deficit; 11 patients had motor deficits, ten patients had sensory deficits, and one patient had both motor and sensory deficits. Most schwannomas occurred in mixed nerves, including the median nerve in 17 patients and tibial nerve in 13 patients. CONCLUSION: The most common site of schwannoma was the median nerve. Although the nerve of origin of the schwannoma could be identified in only 26.0% of cases, the data suggest that schwannomas occur in both sensory and motor nerves.

Peripheral nerve sheath tumors in Neurofibromatosis Type 2: Surgical and histopathologic features.

OBJECTIVE: Management of peripheral nerve sheath tumors (PNST) in Neurofibromatosis Type 2 (NF2) is complicated by frequent involvement of major peripheral nerves and concern that these tumors may be plexiform and/or involve multiple fascicles. Hybrid histologic features of both schwannoma and neurofibroma have been described in NF2-associated tumors, although the incidence of this phenotype in PNSTs is unknown. We sought to define the outcomes of surgery for tumors involving major peripheral nerves in NF2 and identify the rate of hybrid histology in PNSTs. PATIENTS AND METHODS: Functional outcomes of surgery for patients with tumors on major (named) peripheral nerves were recorded. Histopathologic analyses were performed on all available excised tumors. RESULTS: Nineteen operations were performed in 12 patients with NF2, for resection of 28 PNSTs. Among 11 tumors involving major peripheral nerves, 10 involved nerves related to motor function. Presenting symptoms in this group included pain (9) and weakness (4). Median tumor diameter was 3.4 cm (range:2.2-10.3 cm). Gross-total resection was achieved in 10 cases. Motor function was stable/improved in 10 cases but diminished after one case involving a small motor fascicle. All tumors involved a single fascicle. Histopathologic analyses of 21 available specimens revealed 19 pure schwannomas. In two cases (10 %) hybrid features of both schwannoma and neurofibroma were identified, with mast cells within regions consistent with neurofibroma. CONCLUSIONS: PNSTs can be resected safely in NF2, even if they involve major peripheral nerves. A small proportion (10 %) of these tumors harbor hybrid histologic features, which may explain reports of plexiform or multi-fascicular tumors in NF2.

Reversal of neurological deficit after chemotherapy in BCL-6-positive neurolymphomatosis. Case report.

Neurolymphomatosis, the infiltration of the peripheral nervous system (PNS) by malignant lymphatic cells, is a rare condition whose prognosis and treatment are not fully characterized. The authors report the case of a 69-year-old, previously healthy man who had a 1-month history of progressive pain in his right arm and associated weakness of several muscles of the right upper extremity when they first examined him. Initial MR imaging of the right brachial plexus showed no abnormalities, but over 3 months, symptoms gradually progressed to almost complete plegia of his right upper extremity. Subsequent MR imaging of his right brachial plexus showed an enhancing mass of the posterior cord of the plexus that encroached on the other cords. Positron emission tomography confirmed the presence of a hypermetabolic lesion in the right axillary region and also detected an asymptomatic hot spot in the gastric wall. Biopsy of the gastric lesion demonstrated a CD20+, diffuse large B-cell lymphoma that was immunohistochemically positive for BCL-6 and negative for p16. The patient underwent 6 cycles of dose-adjusted etoposide-vincristine-doxorubicin-cyclophosphamide-prednisone (EPOCH) and rituximab, intermixed with 3 cycles of high-dose intravenous and intrathecal methotrexate, and followed by 6 monthly doses of rituximab for consolidation. Follow-up MR imaging and PET of the plexus showed complete radiological response after 3 months of treatment, as demonstrated by normalization of brachial plexus caliber, contrast enhancement, and metabolic activity. Twenty-eight months after symptom onset and 20 months after beginning therapy, the patient was disease-free, had recovered most upper extremity neurological function, and had only minimal remaining weakness of the right wrist and finger extension.

Management of brachial plexus region tumours and tumour-like conditions: relevant diagnostic and surgical features in a consecutive series of eighteen patients.

BACKGROUND: Tumours of the brachial plexus region are rare and most publications are case reports or studies with a small series of patients. The aim of this study is to present our experience in managing these lesions. METHODS: We review 18 patients with tumours in the brachial plexus region submitted to surgical treatment in a 6 year period, including their clinical presentation, neuro-imaging data, surgical findings and outcome. FINDINGS: The tumours comprised a heterogeneous group of lesions, including schwannomas, neurofibromas, malignant peripheral nerve sheath tumour (MPNST), sarcomas, metastases, desmoids and an aneurysmal bone cyst. The most common presentation was an expanding lump (83.33%). Eleven tumours were benign and 7 were malignant. Neurofibromatosis was present in only 2 patients (11.11%). Gross total resection was achieved in 14 patients and sub-total resection in the others. Only 3 patients presented with new post-operative motor deficits. The incidence of complications was low (16.5 %). CONCLUSIONS: The majority of tumours were benign and most of them could be excised with a low incidence of additional deficits. Some of the malignant tumours could be controlled by surgery plus adjuvant therapy, but this category is still associated with high morbidity and mortality rates.

Cold intolerance in surgically treated neuroma patients: a prospective follow-up study.

PURPOSE: Cold intolerance may impose great changes on patients' lifestyle, work, and leisure activities, and it is often severely disabling. This study aims to investigate the prevalence and severity of cold intolerance in patients with injury-related neuromas of the upper extremity and improvement of symptoms after surgical treatment. Furthermore, we try to find predictors for cold intolerance and correlations with other symptoms. METHODS: Between January 2006 and February 2009, 34 consecutive patients with surgically treated neuroma-specific neuropathic pain of the upper extremities were sent a questionnaire composed of general questions concerning epidemiologic variables and several specific validated questionnaires, including the Visual Analog Scale for pain. To estimate the prevalence of cold intolerance objectively in neuroma patients, we used the validated CISS (Cold Intolerance Symptom Severity) questionnaire with a prespecified cutoff point. RESULTS: The CISS questionnaire was filled out by 33 patients before and 30 after surgery for neuroma-specific neuropathic pain, with a mean follow-up time of 24 months. We found a prevalence of cold intolerance of 91% before surgery, with a mean CISS score above the cutoff point for abnormal cold intolerance. After surgery, the prevalence of cold intolerance and the mean CISS score were not significantly different, whereas the mean Visual Analog Scale score decreased significantly (p < .01). CISS scores were lower in patients with neuromas associated with sharp injury of the peripheral nerve (p = .02). A higher VAS score correlated significantly with a higher CISS score (p = .01). CONCLUSIONS: Cold intolerance is a difficult and persistent problem that has a high prevalence in patients with a painful injury-related neuroma. There seems to be a relationship between severity of cold intolerance as measured by CISS, pain as measured by the Visual Analog Scale, and type of injury. Cold intolerance may not disappear with time or surgical treatment. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Surgical treatment of giant benign sacral neurogenic tumors using the posterior-only approach.

OBJECTIVE: Few studies have reported on the effects of surgery on giant benign sacral neurogenic tumors since these tumors represent a major challenge for surgical oncologists. In the present study, we retrospectively reviewed our experiences in performing resections of giant benign sacral neurogenic tumors using the posterior-only approach via "fishing" method, and assessed the outcomes of patients after this procedure. PATIENTS AND METHODS: We retrospectively reviewed and analyzed the records of 155 consecutive patients with giant benign sacral neurogenic tumors who underwent resection by a posterior-only approach in our center from Feb 2008 to Feb 2018. RESULTS: Operations lasted for a mean of 183 ±â€¯37 min (range, 125-230 min). The mean estimated blood loss during the surgery was 1098 ±â€¯889 ml (range, 600-4100 ml). The mean follow-up time was 65 ±â€¯39 months (range, 12-118 months). By the last follow-up, the local recurrence rate was 7.1% (11/155), the combined overall symptom resolution and remission rate was 91.1% (123/135), and the total complication rate was 17.4% (27/155). CONCLUSION: The posterior-only approach is safe and effective in patients with giant benign sacral neurogenic tumors.

Cauda equina tumor mimicking an intradural disc herniation, with emphasis on differential diagnosis--a case report.

We report a rare case of lumbar disc prolapse with intradural schwannoma at the same level. A 33-year-old man had had moderate right leg pain for about four years, which had worsened suddenly when he lifted heavy baggage. MR imaging revealed lumbar disc prolapse at L4/5. An intradural tumor that was iso-intense on T1-weighted and slightly hyperintense on T2-weighted images was also recognized at the same level. The tumor was homogeneously enhanced on Gadolinium-MRI (Gd-MRI). Intractable back and leg pain necessitated surgical treatment, which yielded a definitive diagnosis of the intradural tumor as schwannoma on histological examination. The intractable pain disappeared immediately after surgery. The patient's intractable and prolonged pain appeared to be due to combined compression by the intradural tumor and disc prolapse. The findings of Gadolinium-MRI were helpful in making the diagnosis.

A novel technique for the intraoperative monitoring of detrusor activity in intradural lesions of the cauda equina. Technical note.

BACKGROUND: Intradural pathology in the region of the cauda equina is uncommon and generally comes to attention secondary to pain or neurologic deficit. A number of surgeons choose to excise these lesions under EMG monitoring of the nerve roots supplying the lower extremity muscles, anal sphincter, and detrusor muscle. In this article, the authors describe a detrusor muscle monitoring technique that has been found to be simple, reliable, and cost-effective in the management of intradural pathology of the cauda equina. METHODS: Fourteen consecutive patients with tumors of the cauda equina who underwent surgical management performed using the standard Foley catheter monitoring technique were included in this study and their outcomes analyzed. RESULTS: In 86% of patients, a gross total resection was achieved. Subtotal resections were performed in 2 patients because of involvement of critical nerve roots. In all cases, the nerve roots supplying the detrusor muscle were successfully identified using this technique. No patient suffered a clinically apparent decline in bladder function during the postoperative period. CONCLUSION: The standard Foley catheter detrusor monitoring technique is a simple, reliable, and cost-effective method to identify and prevent injury to the sacral nerve roots innervating the urinary bladder during intradural exploration of the cauda equina.