Fulminant Non-occlusive Mesenteric Ischemia After Head Trauma: Report of Two Cases.

There have been no case reports of non-occlusive mesenteric ischemia (NOMI) following head trauma. Our two patients with non-surgical traumatic intracerebral hemorrhage succumbed to NOMI one week after the injury. Both were women over age 80 years and were clinically improving before NOMI occurred. One patient had been eating since admission, while the other had not, which prompted the initiation of enteral nutrition on day 5. The patients shared many characteristics: 1) over age 80 years; 2) minor brain contusion; 3) constipation for a week; 4) minimal abdominal symptoms; 5) rapidly developing leukocytosis, hyperglycemia, hypernatremia, and elevated blood urea nitrogen; 6) massive diarrhea with a small amount of blood on the same day that laboratory data became abnormal; and 7) fever and shock developed shortly after diarrhea appeared. Because of the fulminant worsening of the condition, shock status, and old age, surgical intervention was considered high risk and not performed in either patient. In retrospect, if NOMI had been diagnosed earlier when the acute pancreatitis-like symptoms began, surgical intervention may have saved their lives. Clinicians should be aware that NOMI can occur after relatively minor head trauma, which can cause death if the diagnosis is delayed.

Subcortical hemorrhage caused by cerebral amyloid angiopathy compared with hypertensive hemorrhage.

OBJECTIVES: Most published reports on lobular hemorrhage in cerebral amyloid angiopathy (CAA) include patients diagnosed only by imaging studies. This study analyzed patients with subcortical hemorrhage histologically diagnosed as CAA or non-CAA (hypertensive). METHODS: This is a retrospective study analyzing data from 100 craniotomy cases. Tissue of hematoma cavity wall was collected for histological investigation in hematoma removal by surgery in patients with subcortical hemorrhage. Statistical analyses of blood pressure, hematoma location and volume, outcome, and mortality was performed in CAA and non-CAA groups. RESULTS: There were 47 CAA and 53 non-CAA cases, and average age was significantly older in the CAA group (p < 0.01). Blood pressure was significantly lower (p < 0.01) but hematoma volume was significantly greater (p < 0.05) in the CAA group. Rebleeding occurred in two CAA cases and one non-CAA case, but no re-operations were required. Average score of modified Rankin Scale, which is used to measure the degree of disability in patients who have had a stroke, at three months after surgery was not significantly different between the two groups (CAA: 3.94 ± 1.28, non-CAA: 3.58 ± 1.50). There were seven deaths in the CAA and six in the non-CAA group, and intraventricular hemorrhage highly complicated in the death cases in both groups. In the CAA group, average age of the fatal cases was significantly older than that of the surviving cases (p < 0.05) and six cases demonstrated dementia before onset of hemorrhage. CONCLUSIONS: Surgical removal of a subcortical hemorrhage caused by CAA is not contraindicated. However, age > 80 years, complication with intraventricular hemorrhage, hematoma volume ≥ 50 ml, and dementia before onset of hemorrhage contribute to high mortality, and craniotomy should be carefully considered for such patients. A limitation of this study is that comparison between CAA and non-CAA groups was performed in the patients with only surgically indicated ICH, and does not evaluate entire ICH cases with CAA. However, this study appropriately compared pathologically diagnosed CAA and non-CAA in patients with moderate to severe lobular ICH with surgical indications.

Midline Shift Induced by the Drainage of Cerebrospinal Fluid in Three Patients With External Decompression.

It is not rare that progressive hydrocephalus worsens clinical conditions in a patient with external decompression and drainage or shunt surgery is required. However, spinal drainage or shunt surgeries potentially carry a risk of causing paradoxical herniation in a patient with decompressive craniectomy, particularly in a comatose case with wide craniectomy. Careful and strict observations are necessary for such patients. In our three comatose cases with craniectomy, paradoxical herniation occurred due to excessive drainage after 5-7 days of shunt surgery and lumbar drainage, although the drainage pressure was set at more than 10 cmH2O. Fortunately, in the three cases, the herniation improved within a few days after the drain was clamped and the bed was flattened. However, the Trendelenburg position and epidural blood patch might be necessary if paradoxical herniation occurs acutely after lumbar puncture or drainage because delayed resolution can be fatal in the herniation.

Primary central nervous system lymphoma (PCNSL) mimicking a falx meningioma with increasingly massive intracerebral hemorrhage.

When using imaging to diagnose brain tumors, it is important to determine whether the tumor is intra- or extra-parenchymal. An 80-year-old man was found on magnetic resonance imaging to have an enhanced mass that appeared to be in the falx and a massive hematoma in the left frontal lobe; the provisional diagnosis was falx meningioma. However, the tumor and hematoma were found intraoperatively to be completely intraparenchymal. Additionally, the falx was intact and not adherent to brain tissue. Malignant lymphoma was diagnosed histologically on the basis of abnormal proliferation of atypical CD20-positive lymphocytes. Cerebral hemorrhage is an extremely rare presentation of primary central nervous system lymphoma. To the best of our knowledge, only 7 cases have been reported. All the reported cases had enhancement in the hematoma; however, in our case, there was definite enhancement outside the hematoma, making the correct diagnosis of lymphoma difficult.

Systematic Review of Spinal Lymphomatoid Granulomatosis Cases.

Lymphomatoid granulomatosis (LYG) is a rare Epstein-Barr virus-associated systemic angiocentric and angiodestructive lymphoproliferative disorder. It commonly involves the lungs and can also affect the skin, liver, kidney, and central nervous system. It can rarely occur in the spine, however, the details are unclear. We performed a systematic review of published cases (including our 1 case) of spinal LYG. We performed a systematic search of studies in English on spinal LYG, focusing on its clinical features, imaging, and treatments, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines on the PubMed database. We identified 14 patients from the literature. We also found 1 case of isolated cervical LYG (grade 3) who was treated with steroid and radiation therapy for the spinal lesion after pathologic diagnosis. We performed a pooled analysis of these 15 cases. The mean age was 43.4 years, and 13 of the 15 patients were male. Brain lesions were present in 11 of 12 intramedullary spinal lesions, and only 1 was an isolated spinal LYG case. Regarding the diagnostic methods, 1 case was not described. Of the 14 cases described, 12 patients underwent biopsies (7 brain, 4 lung, and 1 spinal cord lesion) and 2 underwent surgical removal for an extramedullary lesion. In the overall prognosis from a mean follow-up period of 21.6 months, 4 patients died despite several treatments. Spinal LYG, particularly isolated spinal LYG, is rare. Thus further accumulation of cases may be necessary to better understand its characteristics.

Less Invasive Combined Micro- and Endoscopic Neurolysis of Superficial Peroneal Nerve Entrapment: Technical Note.

As superficial peroneal nerve (S-PN) entrapment neuropathy is relatively rare, it may be an elusive clinical entity. For decompression surgery addressing idiopathic S-PN entrapment, narrow-area decompression may be insufficient and long-area decompression along the S-PN from the peroneus longus muscle (PLM) to the peroneal nerve exit site may be required. To render it is less invasive, we performed S-PN neurolysis in a combined microscope/endoscope procedure. We report our surgical procedure and clinical outcomes. We microsurgically decompressed the affected S-PN under local anesthesia without a proximal tourniquet. We made a small linear skin incision at the distal portion of the S-PN, performed distal decompression of the S-PN where it penetrated the deep fascia, and then performed proximal decompression under an endoscope. At the site where the S-PN exited the PLM, we placed additional small incisions and proceeded to microscopic decompression. We surgically treated three patients with S-PN entrapment. They were two men and one woman ranging in age from 66 to 85 years. The mean postoperative follow-up was 22 months. Their symptoms before treatment and at the latest follow-up visit were recorded on the numerical rating scale (NRS). The mean incision length was 5.5 cm and 17.3 cm of the S-PN was decompressed. All three patients reported postoperative symptom improvement. There were no complications. In patients with idiopathic S-PN entrapment, long-site neurolysis under local anesthesia using a microscope/endoscope combination is useful.

High-frequency thermal coagulation to treat middle cluneal nerve entrapment neuropathy.

OBJECTIVE: Middle cluneal nerve entrapment (MCN-E) around the sacroiliac joint can elicit low back pain (LBP). Pain control can be obtained with anesthetic nerve blocks; however, when their effectiveness is transient, surgical release may be necessary. We investigated the efficacy of radiofrequency thermocoagulation (RFTC) in patients with MCN-E. METHODS: Between December 2018 and August 2019, 11 consecutive patients (4 men, 7 women; mean age 76.4 years) with intractable medial buttock pain due to MCN-E underwent MCN RFTC. The mean symptom duration was 49.5 months; pre-RFTC local MCN blocks provided pain relief for a mean of 7.7 days. The severity of pain in the medial buttock due to MCN-E was recorded before and 2, 6, 12, and 24 weeks after RFTC on the numerical rating scale (NRS) and the Roland-Morris Disability Questionnaire (RDQ). RESULTS: All patients reported pain alleviation; there were no complications. While there was a significant difference in the pre- and post-RFTC treatment NRS (p < 0.05), the RDQ scores were significantly lower only after 12 weeks. The duration of pain relief was significantly prolonged by RFTC (p < 0.05). Two patients suffered pain relapse 10 weeks post-RFTC; pain alleviation was obtained by re-RFTC performed 2 weeks after pain recurrence. Two other patients relapsed 20 and 21 weeks post-RFTC; their symptoms also disappeared by MCN block administered 24 weeks after they had undergone RFTC. CONCLUSION: RFTC may safely control intractable LBP due to MCN-E.

Therapeutic Effect of Mirogabalin on Peripheral Neuropathic Pain due to Lumbar Spine Disease.

STUDY DESIGN: Retrospective study. PURPOSE: This study aims to evaluate the effectiveness of mirogabalin in treatment of peripheral neuropathic pain due to lumbar spine disease. OVERVIEW OF LITERATURE: Mirogabalin is a novel selective ligand for the α2δ subunit of voltage-gated Ca channels. METHODS: Between April and December 2019, we used mirogabalin to treat 60 consecutive patients (mean age, 67.6 years) with leg symptoms due to lumbar disease. The treatment outcome after 8 weeks of mirogabalin therapy was evaluated by comparing the preand post-administration Numerical Rating Scale (NRS) for leg symptoms and sleep disturbance, the NRS and Roland-Morris Disability Questionnaire for low back pain (LBP), and the quality of life (QOL) score (based on EuroQol five-dimension five-level scale). RESULTS: Mirogabalin treatment was stopped at less than eight weeks in eight patients. The remaining 52 patients for evaluation were divided as group 1 (17 patients who presented with leg symptoms that lasted for less than 3 months) and group 2 (35 patients with leg symptoms that lasted longer than 3 months). The leg symptoms and LBP in both groups significantly improved at 4 and 8 weeks of treatment, and sleep disturbance and QOL were improved at 8 weeks as well. Compared to group 2, the pretreatment leg symptoms and QOL were significantly worse in group 1, and their improvement after 8 weeks of mirogabalin treatment was significantly better (p<0.05). Of the 60 original patients, 17 suffered adverse effects, which were mild in 16 patients and required treatment cessation due to excessive weight gain in one patient. CONCLUSIONS: We have validated the effect of mirogabalin on neuropathic pain due to lumbar spine disease, which has effectively addressed the associated leg symptoms, LBP, and sleep disturbance.

Recurrent Cervical Spinal Epidural Hematoma: Case Report and Literature Review.

Spinal epidural hematoma (SEDH) is an uncommon pathology. Here, we report a case of SEDH with recurrences, along with a literature review of relevant cases to identify characteristics of SEDH recurrence. A 13-year-old girl experienced sudden-onset of back pain and bilateral leg weakness. She was diagnosed with a cervical idiopathic epidural hematoma, and the symptoms subsided with conservative management. Four months after the event, she again experienced back pain due to recurrence of the cervical epidural hematoma, but she was observed because no neurological deficits could be detected. Fifteen months after the initial SEDH, she experienced severe back pain and tetra-paresis due to recurrence. The SEDH was located in the left ventral and dorsal aspect at the C6-T1 level, with severe spinal cord compression. The hematoma was removed through left hemilaminectomy. Bleeding was noted from the epidural venous plexus along the left C6 spinal root, which had coagulated. After hematoma resection, her symptoms gradually improved, and she was discharged 3 weeks after surgery without any neurological deficits. No hematoma recurrence has since been experienced. Recurrent SEDH is relatively rare, with only 11 cases previously reported. Recurrent hematoma cases are more common in young, female patients, while SEDH, in general, is more common in males in their late forties. The recurrence interval is shorter in non-surgical cases than those requiring surgery. Knowledge of these characteristics may be useful in the future management of SEDH.

[A Case of Guyon's Canal Syndrome Associated with Cubital Tunnel Syndrome].

A 51-year-old man had a 1-year history of numbness on the ulnar side of the 4th finger, the 5th finger, and the ulnar side of the forearm, and weakness of the right hand. The Spurling sign was negative, and cervical radiography and magnetic resonance imaging revealed no abnormality. The Tinel-like signs at the Guyon's canal and cubital tunnel were positive. The diagnosis upon electrophysiological examination was cubital tunnel syndrome and Guyon's canal syndrome, but the possibility of Guyon's canal syndrome was high. Based on the presence of numbness in the forearm, the Tinel-like sign at the cubital tunnel, and the high incidence rate of cubital tunnel syndrome, an operation for cubital tunnel syndrome was performed. After the first operation, the numbness in the forearm was improved, but numbness in the 4th and 5th fingers, and weakness of the right hand remained, and the Tinel-like sign at the Guyon's canal also remained positive. The second operation for Guyon's canal syndrome was performed a month after the first operation for cubital tunnel syndrome. After the second operation, the residual symptoms improved gradually. Guyon's canal syndrome is a rare condition, but it may be considered a causative factor in patients with ulnar neuropathy.

Is the Vertebral Posterior Line a Safety Landmark for Cervical Posterior Screw Insertion? - Radiological Study of the Vertebral Artery in the Cervical Spine.

At posterior cervical fixation, iatrogenic injury of the vertebral artery (VA) must be avoided. As the VA is usually located in front of the posterior line of the vertebral body, intraoperative lateral fluoroscopy is used to identify the line. We investigated in how many of 105 patients (210 VAs) this line is a safe marker. We also inspected the original cervical magnetic resonance angiograms (MRA) of 105 consecutive patients who had been treated for other than cervical spine diseases to study some anatomical characteristics of the VA in the cervical spine. The distance from the posterior line of the vertebral body to the posterior VA surface was classified as safe, as requiring attention, and as unsafe. Among the 210 VAs, four hypoplastic vessels were excluded from this study; consequently, 206 VAs were available for assessment. The average distance exceeded 6 mm, it was shorter at the upper cervical level. Although in at least 200 VAs (97.1%) the distance between C4 and C7 was safe, in only 170 VAs (82.5%) was it safe at C3. We observed a total of 31 tortuous loops in 17 VAs; their presence had a significant negative effect on the usefulness of the safety line. Although the posterior line of the vertebral body may be useful for safe screw insertion at the C4-C7 level, it may be less useful at C3. In the presence of tortuous VA loops, close attention must be paid to the reliability of the safety line during cervical spine surgery.

Quality of life effects of pain from para-lumbar- and lower extremity entrapment syndrome and carpal tunnel syndrome and comparison of the effectiveness of surgery.

INTRODUCTION: We compared the preoperative quality of life (QOL) of patients with carpal tunnel syndrome, lower extremity-, and para-lumbar entrapment syndrome, and the effect of surgery on their QOL. PATIENTS AND METHODS: We prospectively enrolled 66 consecutive patients who underwent surgery for carpal tunnel syndrome (group 1, n = 23), lower extremity entrapment syndrome (group 2, n = 22), and para-lumbar entrapment syndrome (group 3, n = 21). Their pre- and postoperative overall health status was assessed on the Medical Outcomes Study Short-Form 36 Health Survey, v2 (SF-36). RESULTS: Except for the mental component summary, the preoperative score for items rated on the SF-36 was significantly lower in group 3 than in groups 1 and 2 (p < 0.05). In all 66 patients, the scores for bodily pain (BP) and the physical component summary (PCS) were significantly lower (p < 0.05) than the national standard, as was the score for physical functioning (PF) in groups 2 and 3. After surgery, PF of group 2 and PF, BP, and PCS of group 3 improved significantly (p < 0.05). CONCLUSION: The detrimental QOL effects are stronger in patients with para-lumbar- or lower extremity entrapment syndrome than in patients with carpal tunnel syndrome.

Incidental Idiopathic Bilateral Pedicle Fracture - Case Report and Literature Review.

In rare cases, pedicle fracture is associated with spine surgery, spondylolysis, or stress fracture. We report a patient without trauma whose bilateral lumbar pedicle fracture was detected incidentally. A 67-year-old woman reported leg numbness and pain. Lumbar MRI showed spinal canal stenosis at the L4/L5 level. Drug treatment was only partially effective. A lumbar computed tomography (CT) scan performed 3 months later revealed bilateral pedicle fracture at L4. A second lumbar MRI showed fresh bilateral L4 pedicle fracture that was not observed on the first scan. Due to the presence of osteoporosis we prescribed daily teriparatide and the wearing of a lumbo-sacral corset. Her subsequent clinical course was uneventful and the fractures fused under conservative treatment. During this period, she had no low back pain (LBP). Only 12 earlier patients with spontaneous bilateral pedicle fracture without trauma, spinal surgery, or bone abnormality have been reported. In 8 patients, including ours, the fracture level was at L4. In all except our patient, LBP was the most common symptom. Pedicle fracture as detected incidentally in our patient. Of the 13 patients, 4 were physically active adolescents; of the 9 others, 5 were women with osteoporosis. Our case is the first report of incidental spontaneous bilateral pedicle fracture.

Undiagnosed Peripheral Nerve Disease in Patients with Failed Lumbar Disc Surgery.

STUDY DESIGN: Retrospective study (level of evidence=3). PURPOSE: We examine the relationship between residual symptoms after discectomy for lumbar disc herniation and peripheral nerve (PN) neuropathy. OVERVIEW OF LITERATURE: Patients may report persistent or recurrent symptoms after lumbar disc herniation surgery; others fail to respond to a variety of treatments. Some PN neuropathies elicit symptoms similar to those of lumbar spine disease. METHODS: We retrospectively analyzed data for 13 patients treated for persistent (n=2) or recurrent (n=11) low back pain (LBP) and/or leg pain after primary lumbar discectomy. RESULTS: Lumbar re-operation was required for four patients (three with recurrent lumbar disc herniation and one with lumbar canal stenosis). Superior cluneal nerve (SCN) entrapment neuropathy (EN) was noted in 12 patients; SCN block improved the symptoms for eight of these patients. In total, nine patients underwent PN surgery (SCN-EN, n=4; peroneal nerve EN, n=3; tarsal tunnel syndrome, n=1). Their symptoms improved significantly. CONCLUSIONS: Concomitant PN disease should be considered for patients with failed back surgery syndrome manifesting as persistent or recurrent LBP.

Deep Decompression of the Lateral Femoral Cutaneous Nerve Under Local Anesthesia.

OBJECTIVE: Meralgia paresthetica is a mononeuropathy of the lateral femoral cutaneous nerve (LFCN) caused by compression around the inguinal ligament. We report a surgical alternative for the treatment of meralgia paresthetica under local anesthesia and its outcomes. METHODS: We operated on 12 patients with unilateral meralgia paresthetica whose age at surgery ranged from 62 to 75 years. The mean postoperative follow-up period was 19 months. Microsurgical deep decompression of LFCN was performed with the patient under local anesthesia. Clinical outcomes of surgical treatment were assessed based on the patient's most recent follow-up visit and were classified into 3 categories: complete, partial, or no relief of symptoms. Symptoms of pain or numbness in the anterolateral part of the thigh were evaluated, using a visual analog scale, before surgery and after surgery, i.e., at the most recent follow-up visit. RESULTS: All patients reported symptom improvement: complete relief in 9 patients (75%) and partial relief in 3 patients (25%). In the 3 patients with partial relief, the remaining symptoms did not affect their daily living. Overall, the visual analog scale scores were significantly improved in all patients (P < 0.05), and no patient experienced postoperative recurrence of their symptoms at the time of the last follow-up visit. CONCLUSIONS: Symptoms of meralgia paresthetica can resemble those of a lumbosacral disorder. Microsurgical deep decompression under local anesthesia produces good surgical outcomes. The use of local anesthesia contributes not only to reduction of pain during surgery but also eliminates excessive surgical procedures and reduces the duration of hospital stay.

[Treatment Results of Low Back and Leg Pain Considering Para-Lumbar Spine Disease and Peripheral Nerve Neuropathy].

INTRODUCTION: Here we report our treatment results of low back and leg pain(LBLP)considering para-lumbar spine disease(PLSD)and peripheral nerve neuropathy(PNN). MATERIALS AND METHODS: We enrolled 103 patients who were admitted to our institute for LBLP treatment between January and December in 2014. For the treatment, we preferentially performed intensive block therapy for PLSD. RESULT: Among 103 patients, 89 patients had PLSD. In 85 patients, we performed intensive block therapy and 82 patients experienced short-term improvement of symptoms. In 35 of these 82 patients, lumbar spine and/or PNN surgical treatment was required as the effect of block therapy was transient. Intensive block therapy was effective in 47 of 103 patients(45.6%), and the remaining patients required surgical treatment(PLSD and/or PNN:31 cases, lumbar spine:13 cases, both:8 cases). CONCLUSION: Among 103 patients with LBLP, intensive block therapy for PLSD and PNN was useful for short-term symptom improvement in 82 patients(79.6%), and for long-term symptom improvement in 47 patients(45.6%)as evaluated at the final follow-up. Surgical treatment of PLSD and/or PNN was required in 39 patients(37.9%). These results suggested that treatment of PLSD and PNN might yield good results for patients with LBLP.

Clinical Features and Surgical Treatment of Superficial Peroneal Nerve Entrapment Neuropathy.

Superficial peroneal nerve (S-PN) entrapment neuropathy (S-PNEN) is comparatively rare and may be an elusive clinical entity. There is yet no established surgical procedure to treat idiopathic S-PNEN. We report our surgical treatment and clinical outcomes. We surgically treated 5 patients (6 sites) with S-PNEN. The 2 men and 3 women ranged in age from 67 to 91 years; one patient presented with bilateral leg involvement. Mean post-operative follow-up was 25.3 months. We recorded their symptoms before- and at the latest follow-up visit after surgery using a Numerical Rating Scale and the Japan Orthopedic Association score to evaluate the affected area. We microsurgically decompressed the affected S-PN under local anesthesia without a proximal tourniquet. We made a linear skin incision along the S-PN and performed wide S-PN decompression from its insertion point at the peroneal tunnel to the peroneus longus muscle (PLM) to the point where the S-PN penetrated the deep fascia. One patient who had undergone decompression in the area of a Tinel-like sign at the initial surgery suffered symptom recurrence and required re-operation 4 months later. We performed additional extensive decompression to address several sites with a Tinel-like sign. All 5 operated patients reported symptom improvement. In patients with idiopathic S-PNEN, neurolysis under local anesthesia may be curative. Decompression involving only the Tinel area may not be sufficient and it may be necessary to include the area from the PLM to the peroneal nerve exit point along the S-PN.

Surgical treatment of middle cluneal nerve entrapment neuropathy: technical note.

OBJECTIVE The etiology of low-back pain (LBP) is heterogeneous and is unknown in some patients with chronic pain. Superior cluneal nerve entrapment has been proposed as a causative factor, and some patients suffer severe symptoms. The middle cluneal nerve (MCN) is also implicated in the elicitation of LBP, and its clinical course and etiology remain unclear. The authors report the preliminary outcomes of a less invasive microsurgical release procedure to address MCN entrapment (MCN-E). METHODS The authors enrolled 11 patients (13 sites) with intractable LBP judged to be due to MCN-E. The group included 3 men and 8 women ranging in age from 52 to 86 years. Microscopic MCN neurolysis was performed under local anesthesia with the patient in the prone position. Postoperatively, all patients were allowed to walk freely with no restrictions. The mean follow-up period was 10.5 months. LBP severity was evaluated on the numerical rating scale (NRS) and by the Japanese Orthopaedic Association (JOA) and the Roland-Morris Disability Questionnaire (RDQ) scores. RESULTS All patients suffered buttock pain, and 9 also had leg symptoms. The symptoms were aggravated by standing, lumbar flexion, rolling over, prolonged sitting, and especially by walking. The numbers of nerve branches addressed during MCN neurolysis were 1 in 9 patients, 2 in 1 patient, and 3 in 1 patient. One patient required reoperation due to insufficient decompression originally. There were no local or systemic complications during or after surgery. Postoperatively, the symptoms of all patients improved statistically significantly; the mean NRS score fell from 7.0 to 1.4, the mean RDQ from 10.8 to 1.4, and the mean JOA score rose from 13.7 to 23.6. CONCLUSIONS Less invasive MCN neurolysis performed under local anesthesia is useful for LBP caused by MCN-E. In patients with intractable LBP, MCN-E should be considered.

Anatomic Variation in Patient with Lateral Femoral Cutaneous Nerve Entrapment Neuropathy.

BACKGROUND: We report a surgical case of entrapment neuropathy of lateral femoral cutaneous nerve (LFCN) with anatomical variation. CASE DESCRIPTION: This 53-year-old man had a 10-year history of paresthesia and pain in the right anterolateral thigh exacerbated by prolonged standing and walking. His symptoms improved completely but transiently by LFCN block. The diagnosis was LFCN entrapment. Because additional treatment with drugs and repeat LFCN block was ineffective, we performed surgical decompression under local anesthesia. A nerve stimulator located the LFCN 4.5 cm medial to the anterior superior iliac spine. It formed a sharp curve and was embedded in connective tissue. Proximal dissection showed it to run parallel to the femoral nerve at the level of the inguinal ligament. The inguinal ligament was partially released to complete dissection/release. Postoperatively, his symptoms improved and the numeric rating scale fell from 8 to 1. CONCLUSION: We report a rare anatomical variation in the course of the LFCN.

Superior and Middle Cluneal Nerve Entrapment as a Cause of Low Back Pain.

Low back pain (LBP) is encountered frequently in clinical practice. The superior and the middle cluneal nerves (SCN and MCN) are cutaneous nerves that are purely sensory. They dominate sensation in the lumbar area and the buttocks, and their entrapment around the iliac crest can elicit LBP. The reported incidence of SCN entrapment (SCN-E) in patients with LBP is 1.6%-14%. SCN-E and MCN entrapment (MCN-E) produce leg symptoms in 47%-84% and 82% of LBP patients, respectively. In such patients, pain is exacerbated by lumbar movements, and the symptoms mimic radiculopathy due to lumbar disorder. As patients with failed back surgery or Parkinson disease also report LBP, the differential diagnosis must include those possibilities. The identification of the trigger point at the entrapment site and the disappearance of symptoms after nerve block are diagnostically important. LBP due to SCN-E or MCN-E can be treated less invasively by nerve block and neurolysis. Spinal surgeons treating patients with LBP should consider SCN-E or MCN-E.