Ganglia-Induced Tarsal Tunnel Syndrome.

BACKGROUND: Tarsal tunnel syndrome (TTS) is a common entrapment neuropathy that is sometimes elicited by ganglia in the tarsal tunnel. METHODS: Between August 2020 and July 2022, we operated on 117 sides with TTS. This retrospective study examined data from 8 consecutive patients (8 sides: 5 men, 3 women; average age 67.8 years) with an extraneural ganglion in the tarsal tunnel. We investigated the clinical characteristics and surgical outcomes for these patients. RESULTS: The mass was palpable through the skin in 1 patient, detected intraoperatively in 1 patient, and visualized on MRI scanning in the other 6 patients. Symptoms involved the medial plantar nerve area (n = 5), lateral plantar nerve area (n = 1), and medial and lateral plantar nerve areas (n = 2). The interval between symptom onset and surgery ranged from 4 to 168 months. Adhesion between large (≥20 mm) ganglia and surrounding tissue and nerves was observed intraoperatively in 4 patients. Of the 8 patients, 7 underwent total ganglion resection. There were no surgery-related complications. On their last postoperative visit, 3 patients with a duration of symptoms not exceeding 10 months reported favorable outcomes. CONCLUSIONS: Because ganglia eliciting TTS are often undetectable by skin palpation, imaging studies may be necessary. Early surgical intervention appears to yield favorable outcomes.

Paralumbar Spine Disease as a Cause of Low Back Pain in Older Adults.

Introduction Low back pain (LBP) is a major contributor to decreases in the ability to perform activities of daily living (ADL) in older adults. Paralumbar spine disease (PLSD) is a common cause of LBP. We aimed to investigate the causes of LBP, including PLSD, among older adults. Methods Among 744 consecutive patients with LBP, 75 patients (10.1%) aged >80 years (25 males and 50 females) were included. The average patient age was 83.9 years. All patients were evaluated using lumbar magnetic resonance imaging (MRI) and radiography to diagnose the causes of LBP. PLSD was diagnosed based on clinical symptoms, palpation, and the effects of the block. Results Eleven patients (11/75, 14.7%) had acute osteoporotic vertebral fractures. Twenty-eight of the remaining 64 patients exhibited decreased LBP with oral medication, and six (6/75, 8.0%) exhibited lumbar spinal canal stenosis on MRI. PLSD was suspected in 19 of the remaining 30 cases based on clinical symptoms and palpation. Blocks were effective in 16 patients with PLSD, which involved superior cluneal nerve entrapment (SCN-E) in eight patients (10.7%), middle cluneal nerve entrapment (MCN-E) in nine patients (12.0%), sacroiliac joint (SIJ) pain in five patients (6.7%), and gluteus medius muscle (GMeM) pain in three patients (4.0%). The average numerical rating scale (NRS) scores for pain changed from 7.5 ± 1.5 before treatment to 1.3 ± 0.9 at discharge (p < 0.05). Conclusion Osteoporotic acute vertebral fracture (14.7%) was identified as the cause of LBP in older adults. Block therapy for PLSD may aid in the diagnosis and treatment of non-specific LBP.

A vertebral artery aneurysm that elicited occipital pain, showed no abnormalities on imaging studies, but ruptured the next day: illustrative case.

BACKGROUND: The authors report the case of a patient with occipital headache whose imaging studies revealed no abnormalities but who died 1 day later due to vertebral artery (VA) aneurysm rupture. OBSERVATIONS: A male in his 40s with no relevant medical history had been taking over-the-counter medication for headache several times a month. One day before he visited our neurosurgery department, he experienced occipital headache, took the usual medicine, and applied a warm compress. Brain magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) studies returned no abnormal findings, and he went home. On the following day, his wife found his lifeless body in rigor mortis and requested a medicolegal autopsy. Preautopsy brain computed tomography showed diffuse subarachnoid hemorrhage (SAH). Histopathologically, there was no obvious VA dissection. The vascular wall at the rupture site lacked internal elastic lamina and media, it was covered only with thin fibrous connective tissue, and the adventitia was expanded. The cause of death was determined to be SAH due to rupture of a VA blister aneurysm. LESSONS: In our patient, brain MRI and MRA studies returned no abnormal findings. However, he died suddenly the next day. Autopsy identified SAH due to rupture of a blister-like VA aneurysm without dissection.

Middle cluneal nerve entrapment sites in the surgical field.

INTRODUCTION: Middle cluneal nerve (MCN) entrapment around the sacroiliac joint elicits low back pain (LBP). For surgical decompression to be successful, the course of the MCN must be known. We retrospectively studied the MCN course in 15 patients who had undergone MCN neurolysis. METHODS: Enrolled in this retrospective study were 15 patients (18 sides). We inspected their surgical records and videos to determine the course of the entrapped MCN. The area between the posterior superior- and the posterior inferior iliac spine was divided into areas A-D from the rostral side. The MCN transit points were identified at the midline and the lateral edge connecting the posterior superior- and posterior inferior iliac spine. Before and 6 months after surgery, the patients recorded the degree of LBP on the numerical rating scale and the Roland-Morris Disability Questionnaire. RESULTS: We decompressed 24 MCNs. The mean number was 1.3 nerves per patient (range 1-2). The MCN course was oblique in the cranio-caudal direction; the nerve tended to be observed in areas C and D. In six patients (40%), we detected two MCN branches, they were in the same area and adjacent. Postoperatively, LBP was improved significantly in all patients. CONCLUSION: Between the posterior superior- and the posterior inferior iliac spine, the MCN ran obliquely in the cranio-caudal direction; it was prominent in areas on the caudal side. In six (40%) patients, we decompressed two adjacent MCNs. Our findings are useful for MCN decompression surgery.

Identification and decompression of superior cluneal nerve implicated in low back pain.

INTRODUCTION: Low back pain (LBP) can be attributable to entrapment of the superior cluneal nerve (SCN) around the iliac crest. Surgical decompression is a useful treatment; however, finding all entrapped SCNs involved in patients with LBP can be difficult. We performed a retrospective study to help identify entrapped SCNs in the narrow surgical field. METHODS: We enrolled 20 LBP patient (22 sides) with SCN entrapment. They were 9 males and 11 females; their mean age was 72.5 years. We developed a 3-step procedure for successful SCN decompression surgery. In step 1, the thoracolumbar fascia is exposed and the SCN penetrating the fascia is released. In step 2, the fascia is opened and the SCN is released. In step 3, the fascia above the iliac crest is opened and the SCN is released. RESULTS: We successfully released 66 nerves; the average was 3.0 ± 0.8 (1-4) per patient. Step 1 detected 18 nerves (27.3%), step 2 identified 35 (53.0%), and in step 3, 13 (19.7%) were recognized. By tracing the thin nerves branching off the SCN, we found 7 nerves (10.6%). We performed 22 operations; step 1 identified 16 SCNs (72.7%), step 2 identified 21 (95.5%), and step 3 found 12 nerves (54.5%). CONCLUSIONS: The SCN is most readily identified upon opening of the thoracolumbar fascia. To identify as many SCN branches as possible, our 3-step method may be useful.

A clinicopathological study of low back pain due to middle cluneal nerve entrapment: case series.

PURPOSE: The middle cluneal nerve (MCN) is a pure sensory nerve around the middle buttock. Its entrapment between the iliac crest and the long posterior sacroiliac ligament elicits low back pain (LBP) that can be treated by MCN neurolysis or neurectomy. Because few studies examined the pathology of MCN entrapment (MCN-E) we subjected 7 neurectomized specimens from 6 LBP patients to pathologic study. METHODS: We present 6 consecutive patients (7 sides) with intractable LBP who underwent successful MCN neurectomy. Their symptom duration ranged from 6 to 96 months (average 47.3 months); the follow-up period ranged from 6 to 17 months (average 11.7 months). The surgical outcomes were evaluated using the numerical rating scale (NRS) for LBP and the Roland-Morris Disability Questionnaire (RDQ) score. The resected MCNs underwent neuropathological analysis. RESULTS: Postoperatively, all 6 patients reported immediate LBP amelioration; their NRS and RDQ scores were improved significantly. Pathological study of the 7 resected nerves showed that the myelinated fiber density was decreased in 6 nerves; we observed marked enlargement (n = 5), perineurial thickening and disruption (n = 6), intrafascicular fibrous changes (n = 5), myelinated fibers separated by fibrous cells under the perineurium (n = 4), and Renaut bodies (n = 3). The 7th nerve appeared normal with respect to the density and size of the myelinated fibers, however, the perineurium was slightly thickened. CONCLUSION: We present pathological evidence at the MCN compression site of 7 nerves from 6 patients whose LBP was alleviated by MCN neurectomy, indicating that MCN entrapment can elicit LBP.

Long-term outcome after surgery for middle cluneal nerve entrapment neuropathy.

PURPOSE: Entrapment of the middle cluneal nerve (MCN-E) can elicit low back pain (LBP). Patients whose LBP responds only transiently to the analgesic effects of MCN blockage may be candidates for surgery. This study addresses its long-term efficacy. METHODS: We initially subjected 34 MCN-E patients (48 sides) to surgical release. Of these, 4 were excluded from this study because their follow-up was shorter than 24 months. The mean age of the 30 included patients was 71.5 years; the mean postoperative follow-up period was 40.4 months. Clinical outcomes were assessed on the Numerical Rating Scale (NRS) for LBP and the Roland Morris Disability Questionnaire (RDQ) before surgery and at the latest follow-up visit. RESULTS: The 30 patients (44 sides) reported severe LBP, leg symptoms were elicited by 32 sides. A mean of 1.4 MCN branches were surgically released, 32 sides were addressed by neurolysis, 7 by neurectomy, and 5 underwent both procedures due to the presence of 2 nerve branches. There were no complications. In the course of a mean follow-up of 26.3 months, MCN-E elicited recurrent symptoms on 6 sides; all had undergone neurolysis or neurectomy and a second operation improved the symptoms. All patients showed significant improvement at the last follow-up visit. Postoperatively both their NRS for LBP and their RDQ scores were improved (pre- vs. postoperative scores, p < 0.05). CONCLUSIONS: While surgical release of MCN-E is expected to yield long-term symptom relief, on 6 of 32 sides (18.8%) treated by neurolysis the patients reported pain recurrence. Whether neurectomy effectively prevents the recurrence of MCN-E in the long term requires further study.

Distal Endovascular Occlusion for Incomplete Occlusion of Cavernous Carotid Aneurysms after High-flow Bypass and Cervical Internal Carotid Artery Ligation.

Internal carotid artery (ICA) ligation for placing a high-flow extracranial-intracranial (EC-IC) bypass is used in patients with aneurysms on the cavernous portion of the ICA. Recanalization and rupture after proximal ICA ligation can occur. We present four patients who underwent endovascular distal ICA occlusion and report our surgical technique and treatment results. We ligated the ICA to place an EC-IC bypass using a radial artery (RA) graft. Failure to obtain spontaneous occlusion in the distal region required endovascular treatment an average of 219 days later. A guide catheter was placed in the common carotid artery, a guide or distal access catheter was introduced in the RA graft from the external carotid artery, and a microcatheter was navigated into the cavernous aneurysm through the RA graft. Using detachable coils, endovascular ICA occlusion was from just distal to the aneurysmal neck to a site proximal to the origin of the ophthalmic artery. Aneurysmal occlusion was completed by endovascular occlusion of the distal ICA. Complications were RA graft stenosis and transient consciousness disturbance due to local subarachnoid hemorrhage. Outpatient follow-up for a mean of 109.5 months revealed no recurrences. Distal occlusion of the ICA through the implanted RA graft is simple and presents a low risk for cerebral infarction due to thrombus formation during the procedure. To treat cavernous carotid aneurysms that do not disappear after placing the EC-IC bypass after ICA ligation at the aneurysmal neck, we offer our procedure as a treatment option.

Transarticular Fixation Using Bioabsorptive Screws for Cervical Lesions.

Transarticular screw fixation is a method for posterior cervical fixation. It is ergonomic because neither connectors nor rods are needed. Biomechanical studies have shown that its fixation force is not inferior to that of lateral mass screws. More information is needed on the surgical outcome of procedures using bioabsorptive screws. We investigated the long-term surgical and radiological outcomes of posterior cervical decompression and fusion using bioabsorptive screws for transarticular fixation.Of 10 patients who underwent cervical spine transarticular fixation using bioabsorptive screws, nine presented with cervical degenerative spondylosis and one with a traumatic cervical spine injury. The mean postoperative follow-up period was 57.1 months. Transarticular screw fixation was successful in all 10 patients; no intraoperative complications were encountered. Bilateral screw breakage was discovered in a patient with cervical spine instability and associated dystonia due to cerebral palsy; there was no symptom deterioration, facet joint breakage, or instability exacerbation. Facet fusion was obtained in the nine other patients. At the patients' last visit, their clinical symptoms were significantly improved. Whole cervical spine alignment (-4.21 ± 7.2 to -5.2 ± 8.7) and the fused segment angle (mean, -0.1 ± 9.9 to -1.2 ± 13.7) did not significantly worsen postoperatively (mean: -0.1 ± 9.9 to -1.2 ± 13.7). Transarticular fixation using bioabsorptive screws is safe and associated with good long-term outcomes. In patients with exacerbation of local instability after posterior decompression, additional transarticular fixation using bioabsorbable screws is a treatment option.

Metastatic Spinal Tumor from Benign Pleomorphic Adenoma: Case Report and Literature Review.

PURPOSE: Pleomorphic adenomas tend to arise in the salivary glands. They are rare and histologically benign but can result in distant metastasis, and their characteristics need further investigation. We report a case of locally recurring benign primary palatal pleomorphic adenoma that resulted in spinal metastases and review the relevant literature. CASE REPORT: A 58-year-old woman had undergone surgery for a palatal pleomorphic adenoma 22 years earlier and 6 subsequent operations for local recurrences. During follow-up, metastases to multiple organs, including the spine, were diagnosed and 4 CyberKnife treatments were performed. She suffered right flank pain and slight paralysis of the right leg; radiological findings showed a growing metastatic spinal tumor. She underwent removal of a thoracic vertebral tumor and posterolateral fusion. Postoperatively, her symptoms improved. Histopathological analysis indicated a pleomorphic adenoma and no evidence of malignancy. Although there was no local recurrence, 23 months after surgery, a fifth CyberKnife procedure was performed for a growing salivary gland tumor and she is currently being followed up. CONCLUSION: We described a rare case of benign pleomorphic adenoma that metastasized to the spine. Long-term follow-up for recurrence and metastasis is required for patients with benign pleomorphic adenoma.

Impact of Dynamic Change of Meandering of Parallel Artery to the Idiopathic Tarsal Tunnel Syndrome.

In idiopathic tarsal tunnel syndrome (TTS), walking seems to make symptoms worse. The findings imply that an ankle movement dynamic component may have an impact on the etiology of idiopathic TTS. We describe how the ankle movement affects the nerve compression caused by the surround tissue, particularly the posterior tibial artery. We enrolled 8 cases (15 sides) that had TTS surgery after tarsal tunnel (TT) MRI preoperatively. Dorsiflexion and plantar flexion were the two separate ankle positions used for the T2* fat suppression 3D and MR Angiography of TT. Based on these findings, we looked at how the two different ankle positions affected the posterior tibial artery's ability to compress the nerve. Additionally, we assessed the posterior tibial artery's distorted angle. We divided the region around the TT into four sections: proximal and distal to the TT and proximal half and distal half to the TT. Major compression cause was posterior tibial artery. Most severe compression point was proximal half in the TT in all cases without one case. In each scenario, the nerve compression worsens by the plantar flexion. The angle of the twisted angle of the posterior tibial artery was significantly worsened by the plantar flexion. In idiopathic TTS, deformation of posterior tibial artery was the primary compression component. Nerve compression was exacerbated by the plantar flexion, and it was attributable with the change of the distorted angle of the posterior tibial artery. This could be a contributing factor of the deteriorating etiology by walking in idiopathic TTS.

Formation of a large fusiform aneurysm next to a medullary infarction due to posterior inferior cerebellar artery dissection.

Posterior inferior cerebellar artery (PICA) infarction can lead to ischemic stroke at the lateral part of the medullary oblongata. PICA dissection can also elicit an ischemic event in this region but its detection on radiological images is difficult due to the small diameter of the vessel. We report a 48-year-old male with Wallenberg syndrome due to PICA dissection, which was difficult to diagnose on first admission. He reported sudden-onset sensory disturbance on the right side of his face, ataxic gait, and headache. Brain magnetic resonance imaging (MRI) revealed a fresh cerebral infarct in the right lateral medulla oblongata. Serial MRI and magnetic resonance angiography (MRA) performed at the time of his admission failed to demonstrate cerebral vessel abnormalities. MRI study performed 18 months after the attack revealed a fusiform aneurysm on the lateral medullary segment of the PICA; its site was extremely close to the cerebral infarct. We concluded that the infarct was due to PICA dissection because it was sudden onset of the symptom at the event and the lesion enlarged dissecting aneurysm located to be coincident with symptoms of Wallenberg syndrome. The aneurysm was trapped, and an occipital artery-PICA bypass was placed. At the latest follow-up, one year after the operation, he manifested no neurological symptoms.Imaging findings at the time of his first admission indicated that the PICA was intact in this patient with Wallenberg syndrome attributable to PICA dissection, which obscured on imaging studies performed at symptom onset and was diagnosed later. However,18 months later, MRI revealed enlargement of an aneurysm at the site of the dissection. A cerebral infarct in the PICA territory in patients with headache may be indicative of PICA dissection.

Mechanical Thrombectomy for Acute Common Carotid Artery Occlusion.

Mechanical thrombectomy (MT) is the standard treatment for acute large occlusion of the cerebral artery. Evidence for the success of this procedure was based on the treatment of patients with internal carotid artery and middle cerebral artery thrombi. There are a few reports on thrombi extending to the common carotid artery (CCA). We document our endovascular procedure and the clinical outcome in seven consecutive patients who underwent MT for CCA thrombi between September 2016 and April 2021. Their mean National Institutes of Health Stroke Scale score was 20.0 (range, 9-30), and the mean diffusion-weighted imaging Alberta Stroke Program Early Computed Tomography Score on magnetic resonance images was 8.7 (range, 7-10). In six patients, MT of the CCA occlusion was successful, and the mean puncture-to-reperfusion time was 84 minutes (range, 39-211 minutes). In five patients, successful reperfusion was obtained. The mean total pass number was 4.1 (range, 2-7). Due to large thrombi, we performed balloon guide catheter (BGC) occlusion in three patients. Sheath occlusion occurred in two, and thrombus migration into the femoral artery around the sheath was observed in two patients. The mean modified Rankin Scale score 3 months post-stroke was 3.6 (range, 2-5). When the removal of a large CCA thrombus is attempted in a single step, catheter and sheath occlusion may occur, and this increases the risk for critical systemic artery occlusion. Therefore, we suggest that MT be combined with the BGC technique and propose the use of a large aspiration catheter to decrease the volume of the thrombus.

Patient Satisfaction with Surgery for Tarsal- and Carpal- Tunnel Syndrome - Comparative Study.

We compared the treatment satisfaction of patients who had undergone surgery for tarsal tunnel syndrome (TTS) and carpal tunnel syndrome (CTS). We enrolled 44 patients in this study; 23 were operated for CTS and 21 for TTS. All patients had received surgery under a microscope and under local anesthesia. Using the numerical rating scale (NRS) for numbness/pain (range 0-10) we compared their preoperative outcome expectations with their satisfaction with our treatment 6 months after the operation. We also recorded their pre- and postoperative EuroQol 5-dimension 5-level (EQ-5D-5L) scale for their health-related quality of life (QOL). The subjective assessment of their QOL showed that it was significantly lower in TTS- than CTS patients both pre- and postoperatively. Six months after the operation, the NRS for symptoms and the (EQ-5D-5L) scale for the QOL were significantly improved in TTS- and CTS patients; however, these scores were significantly better after CTS- than TTS surgery. Also, the postoperative NRS was significantly lower in the CTS- than the TTS patients. Our comparison of the patients' expected- and actual surgical outcome showed that the result was better than expected after CTS- and TTS surgery; in CTS patients the difference was significant. Overall, CTS- were more satisfied than TTS patients with the treatment outcome. Satisfaction with the treatment was greater after CTS- than TTS surgery. TTS- experienced less symptom relief than CTS patients although the actual- exceeded the expected outcome in patients operated for TTS.

Paralysis Immediately after Surgical Decompression for Common Peroneal Nerve Entrapment.

OBJECTIVE: Common peroneal nerve (C-PN) entrapment neuropathy is the most common peripheral nerve neuropathy of the legs. C-PN decompression surgery is less invasive but may result in neurological complications. We report a rare case of nerve paralysis immediately after C-PN decompression surgery. CASE REPORT: An 85-year-old man presented with leg numbness and pain. An electrophysical study revealed C-PN entrapment in the affected area and he underwent surgical decompression. Immediately after the procedure he complained of slight paralysis without pain (manual muscle test: 3/5), which gradually worsened and was complete at 60 min after surgery. We re-opened the skin incision 3 hours after the first operation and found that a subcutaneous suture had been applied to the connective tissue near the C-PN, resulting in marked compression of the nerve. After release of the suture his paralysis improved immediately. We confirmed that there was no other nerve compression and finished the operation. His paralysis disappeared completely. CONCLUSION: Peripheral nerve surgery, including C-PN decompression surgery, is less invasive, and the risk of complications is low. However, because the C-PN is located in the shallow layer under the skin, an excessively deep suture in the subcutaneous layer may compress the nerve and elicit nerve palsy. Therefore, careful postoperative follow-up is necessary because early decompression leads to good surgical results.

Magnetic Resonance Imaging Findings in Patients with Tarsal Tunnel Syndrome.

Tarsal tunnel syndrome (TTS) is a common entrapment syndrome whose diagnosis can be difficult. We compared preoperative magnetic resonance imaging (MRI) and operative findings in 23 consecutive TTS patients (28 sides) whose mean age was 74.5 years. The 1.5T MRI sequence was 3D T2* fat suppression. We compared the MRI findings with surgical records and intraoperative videos to evaluate them. MRI- and surgical findings revealed that a ganglion was involved on one side (3.6%), and the other 27 sides were diagnosed with idiopathic TTS. MRI visualized the nerve compression point on 23 sides (82.1%) but failed to reveal details required for surgical planning. During surgery of the other five sides (17.9%), three involved varices, and on one side each, there was connective tissue entrapment or nerve compression due to small vascular branch strangulation. MRI studies were useful for nerve compression due to a mass lesion or idiopathic factors. Although MRI revealed the compression site, it failed to identify the specific involvement of varices and small vessel branches and the presence of connective tissue entrapment.

Patient satisfaction with cluneal nerve entrapment surgery.

INTRODUCTION: Low back pain (LBP) from superior or middle cluneal nerve entrapment has been addressed surgically. We recorded patient satisfaction with this treatment. METHODS: We included 22 consecutive patients who had undergone surgery for unilateral cluneal nerve entrapment (superior: n = 17, middle: n = 5). The numerical rating scale (NRS) for LBP, the Oswestry Disability Index (ODI) score, and the EuroQOL 5-dimension, 5-level (EQ-5D-5L) scale before and 6 months after the operation were compared. Using these scores, the treatment outcome was compared with the patients' preoperative expectations. RESULTS: LBP was ameliorated in all 22 patients; their NRS, ODI, and EQ-5D-5L were significantly improved after surgery. Surgical satisfaction based on the postoperative NRS scores was recorded as 8.8 ± 1.1 (range 7-10). While the postoperative was significantly better than the expected NRS, the postoperative ODI was significantly higher than expected by the patients (both: p < 0.05). There was a moderate correlation between the postoperative NRS and ODI and postoperative patient satisfaction. CONCLUSION: Patient satisfaction with the surgical result was rated as acceptable.

Morphological changes in vertebral artery dissections observed on 4D flow magnetic resonance images: case report.

The morphology of vertebral artery (VA) dissections can change in the clinical course. A 58-year-old female with a 2-week headache was diagnosed with left VA dissection. Hemodynamic stress on the right VA detected on 4D flow MRI scans resulted in increased wall shear stress but the vessel was morphologically unchanged. Subsequent MRA revealed right VA dissection. Her bilateral dissections were treated conservatively and no neurological abnormality developed. Serial 4D flow MRI may be useful for observing morphological changes in VA dissections and help to clarify the mechanism(s) underlying VA dissections.

External Carotid Artery-Related Adverse Events at Extra-Intra Cranial High Flow Bypass Surgery Using a Radial Artery Graft.

OBJECTIVE: Placing an extracranial-intracranial (EC-IC) high-flow bypass using a radial artery (RA) graft plus internal carotid artery (ICA) trapping or ligation is an option for treating patients expected to be at high risk for complications by direct surgical treatment of the ICA. We focused on the anastomosis between the external carotid artery (ECA) and the RA graft in the cervical region and present adverse events and salvage procedures. METHODS: EC-IC high-flow bypass procedures using an RA graft were performed to treat 87 consecutive patients. The ECA diameter at the midpoint of the planned ECA-RA anastomosis and the non-branched length of the ECA were measured on preoperative angiograms. To study adverse events related to ECA-RA anastomoses, we reviewed the patients' surgical records and intraoperative videos. RESULTS: In 11 patients (12.6%) we encountered adverse events during anastomosis between the ECA and RA. The rate of ECA dissection was significantly higher in male patients (4 of 17; 23.5%) than female patients (3 of 70; 4.3%) (P = 0.012). Logistic regression analysis revealed that male sex, individuals with diabetes mellitus, and patients whose non-branching length of the ECA was short (16.1 ± 6.7 mm) were at high risk of ECA problems. We set the cutoff point at 17.5 mm (the area under the receiver operator characteristic curve was 0.72). CONCLUSIONS: Our findings indicate that patients, especially male patients, treated by EC-IC high-flow bypass using an RA graft are at increased risk for adverse events when the ECA length at the site of the planned anastomosis is shorter than 17.5 mm.

Perioperative Complications and Adverse Events after Surgery for Peripheral Nerve- and Para-lumbar Spine Diseases.

Peripheral nerve diseases are common. Para-lumbar spine diseases (PLSDs) include peripheral neuropathy around the lumbar spine, e.g., cluneal nerve entrapment and gluteus medius muscle pain. While these diseases can be treated by less invasive surgery, postoperative complications have not been sufficiently investigated. We document complications after surgery for peripheral nerve diseases and PLSDs. Between July 2014 and December 2020, 678 consecutive patients with peripheral nerve diseases and PLSDs underwent 1068 surgical procedures (upper limb 200 sites, lower limb 447 sites, para-lumbar spine 394 sites, and tumor 27 sites). After excluding 27 procedures to address tumors, we examined the remaining 1,041 procedures undergone by 672 patients (average age 68.2 years) and recorded the complication rate observed within 30 days after the procedures. The overall surgical complication rate was 3.9% (41/1041 procedures); 6 procedures required surgical salvage and 35 were treated conservatively. There were no long-term sequelae from complications. The complication rate was high after surgery for lateral femoral cutaneous-, saphenous-, and common peroneal nerve entrapment and tarsal tunnel syndrome; all sites involved the lower limbs. As a result, intergroup comparison showed that the complication rate was significantly higher for the upper limb (3.0%) procedures than the lower limb (6.7%) and PLSD (1.3%) procedures. It was significantly lower for PLSD operations than lower and upper limb operations. The patient age and diabetes mellitus were significant risk factors for postoperative complications. Their rate was low in patients treated for peripheral nerve diseases and PLSDs; 34 of the 41 complications (82.9%) were related to the surgical wound.