Prospective Cohort Study with a 2-Year Follow-up of Clinical Results, Fusion Rate, and Muscle Bulk for Uniportal Full Endoscopic Posterolateral Transforaminal Lumbar Interbody Fusion

Methods@#We evaluated patients who underwent EPTLIF with a minimum 24-month follow-up. Clinical parameters of the Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) were measured at the preoperative, 1-week postoperative mark, postoperative 3-month mark, and final follow-up. Preoperative and 1-year postoperative magnetic resonance imaging measurement of preoperative and postoperative Kjaer grade, right and left psoas muscle mass area, and right and left paraspinal muscle mass area was performed. @*Results@#EPTLIF with a minimum 24-month follow-up of 35 levels was included. The complication rate was 6%, and the mean Bridwell’s fusion grade was 1.37 (1–2). There was statistically significant improvement at 1 week, 3 months, and 2 years in VAS (4.11±1.23, 4.94±1.30, and 5.46±1.29) and in ODI (40.34±10.06, 46.69±9.14, and 49.63±8.68), respectively (p <0.05). Successful operation rate with excellent and good MacNab’s criteria at 2 years was 97%. There was an increment of statistically significant bilateral psoas muscle cross-sectional area, right side (70.03±149.1 mm²) and left side (67.59±113.2 mm²) (p <0.05). @*Conclusions@#Uniportal EPTLIF achieved good fusion and improved clinical outcomes with favorable paraspinal musculature bulk at the 2-year follow-up.

Narrative Review of Pathophysiology and Endoscopic Management of Basivertebral and Sinuvertebral Neuropathy for Chronic Back Pain

Chronic lower back pain is a leading cause of disability in musculoskeletal system. Degenerative disc disease is one of the main contributing factor of chronic back pain in the aging population in the world. It is postulated that sinuvertebral nerve and basivertebral nerve main mediator of the nociceptive response in degenerative disc disease as a result of neurotization of sinuvertebral and basivertebral nerve. A review in literature is done on the pathoanatomy, pathophysiology and pain generation pathway in degenerative disc disease and chronic back pain and management strategy is discussed in this review to aid understanding of sinuvertebral and basivertebral neuropathy treatment strategies.

Remodeling of Epidural Fluid Hematoma after Uniportal Lumbar Endoscopic Unilateral Laminotomy with Bilateral Decompression: Comparative Clinical and Radiological Outcomes with a Minimum Follow-up of 2 Years

Methods@#Magnetic resonance imaging (MRI) and clinical evaluation were performed for patients with single-level uniportal endoscopic lumbar decompression with a minimum follow-up of 2 years. @*Results@#A total of 126 patients were recruited with a minimum follow-up of 26 months. The incidence of epidural fluid hematoma was 27%. Postoperative MRI revealed a significant improvement in the postoperative dura sac area at postoperative day 1 and at the upper endplate at 6 months in the hematoma cohort (39.69±15.72 and 26.89±16.58 mm2) as compared with the nonhematoma cohort (48.92±21.36 and 35.1±20.44 mm2), respectively (p <0.05); and at the lower endplate on postoperative 1 day in the hematoma cohort (51.18±24.69 mm2) compared to the nonhematoma cohort (63.91±27.92 mm2) (p <0.05). No significant difference was observed in the dura sac area at postoperative 1 year in both cohorts. The hematoma cohort had statistically significant higher postoperative 1-week Visual Analog Scale (VAS; 3.32±0.68) pain and Oswestry Disability Index (ODI; 32.65±5.56) scores than the nonhematoma cohort (2.99±0.50 and 30.02±4.84, respectively; p <0.05). No significant difference was found at the final follow-up VAS, ODI, and MRI dura sac area. @*Conclusions@#Epidural fluid hematoma is a common early postoperative MRI finding in lumbar endoscopic unilateral laminotomy with bilateral decompression. Conservative management is the preferred treatment option for patients who do not have a neurological deficit. Symptoms last only a few days and are self-limiting. A common endpoint is a remodeled fluid hematoma and the subsequent expansion of the dura sac area.

Advantages of New Endoscopic Unilateral Laminectomy for Bilateral Decompression (ULBD) over Conventional Microscopic ULBD

Background@#Biportal endoscopic unilateral laminectomy for bilateral decompression (ULBD) is an emerging minimally invasive procedure for spinal stenosis. However, reports of the results associated with this surgical method are still lacking. @*Methods@#We conducted a retrospective study of 60 patients who underwent bilateral decompression for lumbar central canal stenosis. The patients were divided into 2 groups according to the surgical method (endoscopic ULBD vs. microscopic ULBD). We compared the outcomes between the 2 groups in terms of postoperative segmental spinal instability, dura expansion, operation time, estimated blood loss, serum creatine kinase (CK), serum C-reactive protein (CRP), visual analog scale (VAS) score, Oswestry Disability Index (ODI), modified MacNab score, and the incidence of complications. @*Results@#The mean VAS, ODI, and modified MacNab score improved significantly from the preoperative period to the last follow-up in both groups and were better in the endoscopic ULBD group until the first day after treatment. The degree of horizontal displacement was lower in the endoscopic ULBD group than in the microscopic ULBD group at postoperative 12 months. Dura expansion, operation time, and estimated blood loss did not differ significantly between the 2 groups. Serum CK and CRP on the first day after treatment were lower in the endoscopic ULBD group than in the microscopic ULBD group. @*Conclusions@#This study shows that both endoscopic ULBD and microscopic ULBD can provide favorable outcomes for lumbar central canal stenosis. However, compared to microscopic ULBD, endoscopic ULBD has advantages in terms of postoperative segmental spinal instability, pain control, and serum CK and CRP.

Lumbar Disc Herniation Presented with Contralateral Symptoms

OBJECTIVE: This study aimed to unravel the putative mechanism underlying the neurologic deficits contralateral to the side with lumbar disc herniation (LDH) and to elucidate the treatment for this condition. METHODS: From January 2009 to June 2015, 8 patients with LDH with predominantly contralateral neurologic deficits underwent surgical treatment on the side with LDH with or without decompressing the symptomatic side. A retrospective review of charts and radiological records of these 8 patients was performed. The putative mechanisms underlying the associated contralateral neurological deficits, magnetic resonance imaging (MRI), electromyography (EMG), and the adequate surgical approach are discussed here. RESULTS: MRI revealed a similar laterally skewed paramedian disc herniation, with the apex deviated from the symptomatic side rather than directly compressing the nerve root; this condition may generate a contralateral traction force. EMG revealed radiculopathies in both sides of 6 patients and in the herniated side of 2 patients. Based on EMG findings and the existence of suspicious lateral recess stenosis of the symptomatic side, 6 patients underwent bilateral decompression of nerve roots and 2 were subjected to a microscopic discectomy to treat the asymptomatic disc herniation. No specific conditions such as venous congestion, nerve root anomaly or epidural lipomatosis were observed, which may be considered the putative pathomechanism causing the contralateral neurological deficits. The symptoms resolved significantly after surgery. CONCLUSION: The traction force generated on the contralateral side and lateral recess stenosis, rather than direct compression, may cause the contralateral neurologic deficits observed in LDH.

Clinical Features of Herniated Disc at Cervicothoracic Junction Level Treated by Anterior Approach

OBJECTIVE: The anterior approach for C7-T1 disc herniation may be challenging because of obstruction by the manubrium and the narrow operative field. This study aimed to investigate the clinical and neurological outcomes of anterior approach for C7-T1 disc herniation. METHODS: We retrospectively evaluated 13 patients who underwent the anterior approach for C7-T1 disc herniation by a single surgeon within a period of 11 years (2003-2014). The minimum follow-up duration was 6 months. We describe the clinical presentation, radiographic findings, neurological outcome, and related complications. RESULTS: Of 372 patients with single-level anterior discectomy and fusion or artificial disc replacement for cervical disc herniation, 13 (3.5%) had C7-T1 disc herniation. The main clinical presentation was unilateral motor weakness in intrinsic hand muscles (11 patients), along with numbness, pain, and tingling sensation that radiate down the arm to the little finger. Most of the patients improved after surgery via the anterior approach. Ten patients underwent successful anterior discectomy and fusion by the standard supramanubrial Smith-Robinson approach, but 2 needed additional manubriotomy and sternotomy. In 1 patient, we performed surgery at a wrong level because the correct level was difficult to identify intraoperatively. Two patients had transient vocal dysfunction, but none had major complications related to injuries of the great vessels such as the thoracic duct or esophagus. CONCLUSION: For patients who require direct anterior decompression for C7-T1 disc herniation, the anterior approach is relatively feasible. However, care should be taken to overcome physical constraints by the manubrium and slope.

Cement Leakage into Adjacent Vertebral Body Following Percutaneous Vertebroplasty

Percutaneous vertebroplasty (PV) is a minimally invasive procedure for osteoporotic vertebral compression fractures that fail to respond to conventional conservative treatment. It significantly improves intolerable back pain within hours, and has a low complication rate. Although rare, PV is not free of complications, most of which are directly related to cement leakage. Because of its association with new adjacent fracture, the importance of cement leakage into the adjacent disc space is paramount. Here, we report an interesting case of cement leakage into the adjacent upper vertebral body as well as disc space following PV. To the best of our knowledge, there has been no report of cement leakage into the adjacent vertebral body following PV. This rare case is presented along with a review of the literature.

Treatment for Acute Stage Complex Regional Pain Syndrome Type II with Polydeoxyribonucleotide Injection

Complex regional pain syndrome (CRPS) type II is a syndrome that develops after nerve injury. Symptoms may be severe, and vary depending on the degree of sympathetic nerve involvement. As yet, there is no satisfactory treatment. We report the case of a female patient who had an L5 left transverse process fracture and an S2 body fracture, who developed symptoms of CRPS type II in her left lower leg that were aggravated during ambulation in spite of absolute bed rest for one month after the trauma. Several treatments, including bed rest, medication, and numerous nerve blocks were attempted, but the pain persisted. We finally tried injection of polydeoxyribonucleotide (PDRN) solution at the left L5 transverse process fracture site because we knew of the anti-inflammatory effect of PDRN. One day after this treatment, her symptoms had almost disappeared and three days later, she was discharged. We will also further discuss the possibility of using PDRN solution for the treatment of CRPS.

Clinical Analysis of Acute Radiculopathy after Osteoporotic Lumbar Compression Fracture

OBJECTIVE: The purpose of this study was to analyze the relationship between fracture pattern and the development of acute radiculopathy after osteoporotic lumbar compression fracture. METHODS: This study included 59 patients who underwent bone cement augmentation for osteoporotic compression fracture below the L2 level, which can lead to radiculopathic radiating pain. The patients were divided into two groups according to the presence of radiculopathy (group A : back pain only; group B : back pain with newly developed radiating pain). We categorized compression fractures into three types by the position of the fracture line. The incidence of newly developed radiculopathy was examined retrospectively for each compression fracture type. RESULTS: The overall incidence of newly developed leg pain (group B) was 25%, and the frequency increased with descending spinal levels (L2 : 0%, L3 : 22%, L4 : 43%, and L5 : 63%). The back pain-only group (group A) had mostly superior-type fractures. On the other hand, the back pain with radiculopathy group (group B) had mostly inferior-type fractures. Most patients in group B showed significant relief of leg pain as well as back pain after bone cement augmentation. CONCLUSION: The incidence of a newly developed, radiating pain after osteoporotic compression fractures increased gradually from the L3 to L5 levels. Most of these fractures were of the inferior type, and the bone cement augmentation procedures seemed to be sufficient for relief of both back and radiating pain.

Rapid Resolution of Traumatic Pneumatocyst in the Cervical Spine: A Case Report

Intraosseous pneumatocyst is a benign, gas-filled, cystic lesion, and is commonly encountered in iliac bone or sacrum. Other locations of this lesion following trauma are rare, and only a handful of isolated cases have been reported. The pathogenesis and etiologies of this uncommon entity are various and it can present a diagnostic challenge. Only four previous cases have described the natural course of intravertebral pneumatocysts. Here, the authors report a rare case of traumatic pneumatocyst, which resolved rapidly without further complication. Possible pathogenic mechanisms are discussed and reviews of literatures are included.

Lying Down Instability Undetected on Standing Dynamic Radiographs

It is well known that spinal instability should be evaluated in the standing lateral position. Standing dynamic flexion and extension radiographs are usually used to assess spinal instability. Here, we report a patient who experienced distraction instability while in the supine position rather than the standard standing position. To our knowledge, this is the first report of lying-down instability undetected on standing dynamic flexion and extension radiographs. We discuss the pathophysiological mechanism of this uncommon but possible entity and provide a review of the literature.

Contralateral Juxtafacet Cyst Development after the Spontaneous Resolution of a Previous Facet Cyst

Juxtafacet cysts are implicated in neural compression. Thus far, it is known that surgical removal is the definitive treatment for symptomatic juxtafacet cyst because spontaneous regression is rare, and the failure rate of conservative treatment is high. We have reported a rare case of right-sided juxtafacet cyst development after the spontaneous resolution of contralateral left-sided facet cyst. The left-sided facet cyst resolved spontaneously without surgical treatment, but a juxtacyst developed on the contralateral facet on the right side, as illustrated on 4-year follow-up magnetic resonance images. To the best of our knowledge, this is the first report of newly developed contralateral juxtafacet cyst after spontaneous regression. Herein, we have discussed the natural history and the management of this rare case.

Minimally Invasive Extraforaminal Lumbar Interbody Fusion for Revision Surgery: A Technique through Kambin's Triangle

OBJECTIVE: The purpose of this study was to evaluate the clinical outcomes of minimally invasive extraforaminal lumbar interbody fusion (ELIF) for revision surgery. METHODS: From January 2011 to December 2012, 12 patients who underwent minimally invasive ELIF through the Kambin's triangle for revision surgery were included in this study. All patients underwent the surgical procedure in the following sequence: (1) epidural anesthesia, (2) exposing the Kambin's triangle toward the lateral part of the dura (partial resection of the superior articular process), (3) bilateral cage insertion for reinforcement of stabilization and fusion, and (4) percutaneous transpedicular screwing. Clinical outcomes were assessed using the visual analogue scale (VAS), and Oswestry disability index (ODI). Imaging and clinical findings including surgical techniques, clinical outcomes, and related complications were depicted and analyzed. RESULTS: The mean age of the patients (5 men, 7 women) was 60.7+/-13.4 years, and the mean follow-up period was 27.1+/-4.9 months. The mean VAS (back and leg) score improved significantly at final follow-up. The mean ODI score decreased as follows: preoperative, 76.78+/-6.08; 3 months after the surgery, 37.74+/-6.67; and at final follow-up, 29.91+/-2.98. Two patients presented with transient nerve root irritation, but there were no cases of incidental dural tear or serious infection. No significant neurological deterioration or major complication was noted in any of the patients. CONCLUSION: Minimally invasive ELIF for revision surgery is an effective surgical option with a low complication rate.

Cauda Equina Syndrome Caused by Idiopathic Epidural Lipomatosis

Spinal epidural lipomatosis (SEL) is a rare condition that presents as a back pain with progressive neurologic symptoms. Most affected patients are obese and receiving steroid therapy, or have an endocrinopathies. We report a rare case of cauda equina syndrome caused by SEL in a non-obese healthy young man without any evident traumatic episode. A healthy 19-year-old man, who had experienced lower back pain for two months, visited our emergency room because of the sudden development of motor weakness and voiding difficulty. Lumbar magnetic resonance image revealed extradural fat compressing the cauda equina. Urgent decompression via posterior laminectomy and excision of excess epidural fat resulted in an immediate symptom improvement.

Mini-open PLIF for Moderate to High Grade Spondylolisthesis: Technique to Achieve Spontaneous Reduction

OBJECTIVE: The purpose of this study was to evaluate the surgical technique and outcome of mini-open posterior lumbar interbody fusion (PLIF) under circumferential releasing technique. METHODS: Fourty patients who underwent mini-open PLIF using the percutaneous screw fixation system for Meyerding Grade II spondylolisthesis or more were retrospectively studied. After complete circumferential release, the slipped vertebrae would tend to obtain spontaneous reduction, and with compressive force by percutaneous screw fixation, additional reduction could be achieved. The radiological measurements including slippage reduction, disc height, restoration of lumbar lordotic angle and focal segmental angle were analyzed. The clinical outcome was assessed using the visual analog scale (VAS) and low back outcome score (LBOS), and procedure related complications were also analyzed. RESULTS: Slippage percentage was improved from 38.0+/-12.6% to 9.3+/-7.8% and lumbar lordotic angle was changed from 43.0+/-13.8degrees to 48.2+/-10.3degrees. Focal segmental angle improved from 10.1+/-8.5degrees to 15.9+/-6.0degrees. The mean LBOS and mean pain score were also improved significantly. Complications included one case of medial penetration of pedicle border and two cases of transient radiculopathy. However, there were no signs of neurological aggravation or fusion failure during the follow-up period. CONCLUSION: Mini-open PLIF using the percutaneous screw fixation following complete circumferential release can be safe and effective treatment for even moderate to severe grade spondylolisthesis.

Bone Cement-Augmented Percutaneous Short Segment Fixation: An Effective Treatment for Kummell's Disease?

OBJECTIVE: The aim of this prospective study was to evaluate the efficacy of bone cement-augmented percutaneous short segment fixation for treating Kummell's disease accompanied by severe osteoporosis. METHODS: From 2009 to 2013, ten patients with single-level Kummell's disease accompanied by severe osteoporosis were enrolled in this study. After postural reduction for 1-2 days, bone cement-augmented percutaneous short segment fixation was performed at one level above, one level below, and at the collapsed vertebra. Clinical results, radiological parameters, and related complications were assessed preoperatively and at 1 month and 12 months after surgery. RESULTS: Prior to surgery, the mean pain score on the visual analogue scale was 8.5+/-1.5. One month after the procedure, this score improved to 2.2+/-2.0 and the improvement was maintained at 12 months after surgery. The mean preoperative vertebral height loss was 48.2+/-10.5%, and the surgical procedure reduced this loss to 22.5+/-12.4%. In spite of some recurrent height loss, significant improvement was achieved at 12 months after surgery compared to preoperative values. The kyphotic angle improved significantly from 22.4+/-4.9degrees before the procedure to 10.1+/-3.8degrees after surgery and the improved angle was maintained at 12 months after surgery despite a slight correction loss. No patient sustained adjacent fractures after bone cement-augmented percutaneous short segment fixation during the follow-up period. Asymptomatic cement leakage into the paravertebral area was observed in one patient, but no major complications were seen. CONCLUSION: Bone cement-augmented percutaneous short segment fixation can be an effective and safe procedure for Kummell's disease.

Complete Separation of the Vertebral Body Associated with a Schmorl's Node Accompanying Severe Osteoporosis

A Schmorl's node is defined as a simple endplate intravertebral herniation resulting from trauma or idiopathic causes. Although Schmorl's nodes have been considered clinically insignificant, they might indicate an active symptomatic process or cause serious complications. In this study, we report an interesting case of complete separation of a vertebral body caused by an untreated Schmorl's node accompanying severe osteoporosis. To our knowledge, this is the first clinical report in the published literature to evaluate the complete separation of a vertebral body associated with a Schmorl's node.

Unilateral Pedicle Fracture Accompanying Spondylolytic Spondylolisthesis

Unilateral pedicle stress fracture accompanying spondylolytic spondylolisthesis is rare even in the elderly. Most are associated with major trauma, previous spine surgery, or stress-related activity. Here, the authors describe an unique case of unilateral pedicle fracture associated with spondylolytic spondylolisthesis at the L5 level, which was successfully treated by posterior lumbar interbody fusion with screw fixation at the L5-S1 level. As far as the authors' knowledge, no such case has been previously reported in the literature. The pathophysiological mechanism of this uncommon entity is discussed and a review of relevant literature is included.

Lumbar Disc Herniation Combined with Posterior Apophyseal Ring Separation in a Young Child: A Case Report

Lumbar disc herniation in children aged 10 years or less is extremely uncommon and posterior apophyseal ring separation is not a common injury that usually occurs in adolescents or young adults after a sports-related microtraumatism. The authors report an unique case of 10-year-old boy who presented with low back pain and radiating pain on both legs. The boy received conservative treatment, which included anti-inflammatory medication, muscle relaxants, and physical therapy, but symptoms were not improved. Computed tomography and magnetic resonance imaging revealed a huge central disc herniation combined with posterior apophyseal ring separation. Microscopic lumbar discectomy with the removal of apophyseal ring separation was performed due to the intractable pain. At six months after surgery, the child was symptom free.

Implant Removal after Percutaneous Short Segment Fixation for Thoracolumbar Burst Fracture : Does It Preserve Motion?

OBJECTIVE: The purpose of this study was to evaluate the efficacy of implant removal of percutaneous short segment fixation after vertebral fracture consolidation in terms of motion preservation. METHODS: Between May 2007 and January 2011, 44 patients underwent percutaneous short segment screw fixation due to a thoracolumbar burst fracture. Sixteen of these patients, who underwent implant removal 12 months after screw fixation, were enrolled in this study. Motor power was intact in all patients, despite significant vertebral height loss and canal compromise. The patients were divided into two groups by degree of osteoporosis : Group A (n=8), the non-osteoporotic group, and Group B (n=8), the osteoporotic group. Imaging and clinical findings including vertebral height loss, kyphotic angle, range of motion (ROM), and complications were analyzed. RESULTS: Significant pain relief was achieved in both groups at final follow-up versus preoperative values. In terms of vertebral height loss, both groups showed significant improvement at 12 months after screw fixation and restored vertebral height was maintained to final follow-up in spite of some correction loss. ROM (measured using Cobb's method) in flexion and extension in Group A was 10.5degrees (19.5/9.0degrees) at last follow-up, and in Group B was 10.2degrees (18.8/8.6degrees) at last follow-up. Both groups showed marked improvement in ROM as compared with the screw fixation state, which was considered motionless. CONCLUSION: Removal of percutaneous implants after vertebral fracture consolidation can be an effective treatment to preserve motion regardless of osteoporosis for thoracolumbar burst fractures.