Dorsal Epidural Gas after Lumbar Microdiskectomy Treated with CT-guided Needle Aspiration.

To present a case of unusual dorsal epidural gas (EG) accumulation after a simple lumbar microdiskectomy (MD), treated with computed tomography (CT)-guided needle aspiration. A 78-year-old woman underwent simple lumbar MD at the L3-4 level. One week after the operation, the patient complained of severe back pain radiating to the right thigh. Follow-up magnetic resonance imaging (MRI) and CT revealed huge EG formation at the dorsal L3-4 epidural space. Conservative treatment did not resolve the patient's pain. We performed CT-guided needle aspiration after 1 week of conservative treatment. The patient's pain fully resolved after aspiration, but it recurred 1 week later. Follow-up MRI and CT revealed re-accumulation of the dorsal EG at the L3-4 level. CT-guided needle aspiration was repeated, again leading to full pain resolution. Follow-up CT 6 months after the second aspiration showed no recurrent dorsal EG. The patient has been symptom-free for 1 year since the second aspiration. CT-guided needle aspiration is a safe and effective alternative to re-operation in the context of dorsal EG formation after MD.

Percutaneous endoscopic lumbar discectomy for L5-S1 disc herniation: transforaminal versus interlaminar approach.

BACKGROUND: Percutaneous endoscopic lumbar discectomy (PELD) is a minimally invasive spinal technique. The unique anatomic features of the L5-S1 space include a large facet joint, narrow foramen, small disc space, and a wide interlaminar space. PELD can be performed via 2 routes, transforaminal (TF-PELD) or interlaminar (IL-PELD). However, it is questionable that the decision of the endoscopic route for L5-S1 discs only depends on the surgeon's preference and anatomic relation between iliac bone and disc space. Thus far, no study has compared TF-PELD with IL-PELD for L5-S1 disc herniation. OBJECTIVE: The goal of this study was to compare the radiologic features and results of TF-PELD and IL-PELD. We have clarified the patient selection for the PELD route for L5-S1 disc herniation. STUDY DESIGN: Retrospective evaluation. METHODS: Thirty consecutive patients each were treated with TF-PELD and IL-PELD for L5-S1 disc herniation in 2 institutes, respectively. Radiological assessments were performed pre- and postoperatively. The disc type, disc size, location, migration, disc height, foraminal height, iliolumbar angle, iliac height, and interlaminar space were analyzed. Clinical data were compared with a 2-year follow-up period. Pre- and postoperative pain was measured using a visual analog scale (VAS; 0 - 10) and functional status was assessed using the Oswestry Disability Index (ODI; 0 - 100%) and the time to return to work. RESULTS: In the 2 groups, the mean VAS scores for back and leg pain, as well as the ODI, were significantly improved. The mean time to return to work was 4.9 weeks with TF-PELD and 4.4 weeks with IL-PELD. Incomplete removal, resulting in the need for subsequent open surgery, occurred in one case (3.3%) of TF-PELD and in 2 cases (6.6%) of IL-PELD. Postoperative dysesthesia developed in 2 patients (6.7%) after IL-PELD; however, there was no dysesthesia after TF-PELD. Recurrence occurred in 3.3% with TF-PELD and in 6.7% with IL-PELD during the 2-year follow-up. A significant difference between groups was demonstrated in terms of disc type, location, and migration. The prevalence of axillary disc herniation (20 cases, 66.7%) was higher than that of shoulder disc herniation (10 cases, 33.3%) in the IL-PELD group. On the other hand, in the TF-PELD group, shoulder disc herniation (20 cases, 66.7%) was more prevalent than the axillary type (10 cases, 33.3%; P = 0.01). A higher number of patients in the TF-PELD group had central disc herniation (10 cases, 33.3%) compared with that in the IL-PELD group (2 cases, 6.7%; P = 0.01). Eleven cases (36.7%) of high grade migration were removed using IL-PELD and one case (6.7%) was removed using TF-PELD (P = 0.01). TF-PELD was used to remov only 3 cases of recurrent disc herniation. There were no significant differences of radiologic parameters between the iliac bone and L5-S1 disc space between the 2 groups. LIMITATIONS: This study has a relatively small sample size and a short follow-up period. CONCLUSION: This study demonstrated that TF-PELD is preferred for shoulder type, centrally located, and recurrent disc herniation, while IL-PELD is preferred for axillary type and migrated discs, especially those of a high grade.

Motor palsy after posterior cervical foraminotomy: anatomical consideration.

BACKGROUND: Motor palsy is a serious complication that can result from cervical surgery. We introduced cases of motor palsy after posterior cervical foraminotomy (PCF) and consider cervical anatomy. METHODS: Between January 2007 and August 2010, 133 PCFs were performed on 106 consecutive patients with radiculopathy caused by foraminal stenosis or posterolateral disc herniation. RESULTS: Three of 133 (2.3%) levels that underwent PCF developed a motor palsy. Two cases involved the C5 nerve root, and one case involved the C6 nerve root. The cause of the C5 palsy may have been excessive retraction, whereas the cause of the C6 palsy may have been thermal damage caused by drilling. The rate of C5 palsy (22.2%) was much higher than that seen with other nerves. Anatomically, the C5 nerve root is thinner and covers the entire intervertebral disc at a relatively sharper angle than the other nerve roots. The removal of an extruded disc at C4-5 forces more excessive retraction of the C5 nerve root. CONCLUSIONS: Although PCF is a good alternative treatment with minimal morbidity for cervical radiculopathy, surgeons should keep in mind the possibility of motor palsy, especially at C4-5.

Laser-assisted posterior cervical foraminotomy and discectomy for lateral and foraminal cervical disc herniation.

OBJECTIVE: Posterior cervical foraminotomy and discectomy (PCFD) is regarded as an effective treatment option for cervical radiculopathy. However, limited exposure of the disc space is one of its major disadvantages. To address this problem, we used a CO(2) laser for sophisticated decompression. The purpose of this study was to demonstrate the clinical outcomes of laser-assisted PCFD and to discuss the benefits of laser use. METHODS: A total of 47 consecutive patients with cervical radiculopathy were treated with PCFD. Among them, 24 patients were treated with laser-assisted PCFD, and the remaining 23 patients were treated with conventional PCFD. After standard posterior cervical microscopic foraminotomy, a microscopic CO(2) laser was used for selective discectomy in the laser PCFD group. Clinical data were compared with a minimum 2-year follow-up period. Clinical outcomes were evaluated using the visual analogue scale (VAS), Neck Disability Index (NDI), and modified MacNab criteria. RESULTS: The clinical outcomes of the two groups were similar. The mean VAS score for radicular arm pain improved from 7.42 to 1.83 in the laser PCFD group and from 8.30 to 1.65 in the conventional PCFD group. The mean NDI improved from 47.00% to 10.46% in the laser PCFD group and from 53.86% to 10.02% in the conventional PCFD group. The rate of excellent or good outcomes was 87.5% for the laser PCFD group and 86.9% for the conventional PCFD group. A significant difference between the groups was found for intraoperative bleeding. The laser PCFD group had significantly lower estimated blood loss values than did the conventional PCFD group (p<0.05). CONCLUSIONS: Laser-assisted PCFD is an efficacious surgical option for treating lateral cervical disc herniation. The pinpoint accuracy of the laser scalpel facilitates sophisticated decompression within a limited surgical field, and may reduce the risk of intraoperative bleeding and neural damage.

Rapid progression of spinal epidural lipomatosis.

Spinal epidural lipomatosis (SEL) is a rare but well-recognized condition. In general, the onset of its symptoms is insidious and the disease progresses slowly. We report two cases of rapid progression of SEL with no history of steroid intake in non-obese individuals after epidural steroid injection. These SEL patients developed neurologic symptoms after less than 5 months; these symptoms were confirmed to be due to SEL by serial MR images. After the debulking of the epidural fat, their symptoms improved.

Changes in back pain after percutaneous endoscopic lumbar discectomy and annuloplasty for lumbar disc herniation: a prospective study.

OBJECTIVE: Percutaneous endoscopic lumbar discectomy and annuloplasty (PELDA) is a minimally invasive spinal technique for lumbar disc herniation. Following discectomy, the relief of leg pain is common; however, the relief of back pain is less predictable. The purpose of this study was to evaluate changes in back pain and to examine the predisposing factors for postoperative back pain following PELDA. DESIGN: In this prospective study, 58 patients with leg and back pain associated with disc herniation underwent PELDA. The patients were divided into two groups: unfavorable and favorable. Patients were defined as having unfavorable outcomes if the percentage improvement of back pain <50% or the postoperative Oswestry Disability Index (ODI) >20% at postoperative 24 months. The preoperative demographic, clinical, and radiologic factors for each group were statistically analyzed. RESULTS: Fifty-two patients were enrolled in this study. The mean visual analog scale scores for back pain and the ODI scores significantly improved from 6.6 and 55.9% preoperatively to 2.5 and 12.7% at the 24-month follow-up. The surgical satisfaction rate was 78.4% at the final follow-up. Eighteen (34.6%) patients had unfavorable outcomes. Patients with advanced disc degeneration of operative levels had significantly worse outcomes than those with mild disc degeneration (odds ratio: 6.316, 95% confidence interval 1.25-31.86, P < 0.05). The severity of postoperative back pain was negatively correlated with surgical satisfaction (correlation coefficient: -0.564, P = 0.00). CONCLUSION: PELDA can relieve back pain as well as leg pain through direct decompression and thermal ablation of the annular defect. Disc degeneration can be expected to influence clinical outcomes following PELDA.

Failed anterior lumbar interbody fusion due to incomplete foraminal decompression.

BACKGROUND: Anterior lumbar interbody fusion (ALIF) has gained widespread popularity for spinal disorders requiring fusion. The purpose of this study was to analyze ALIF failures. METHODS: The medical records of 223 patients treated with ALIF between January 2007 and June 2008 were retrospectively reviewed. Patients with unfavorable outcomes, including subsequent posterior decompression at the index level or poor outcomes after ALIF were identified based on clinical and radiological findings. The patients were divided into two groups: an unfavorable group and a favorable group. Preoperative clinical and radiological factors for each group were statistically analyzed. RESULTS: Two hundred of the 223 patients were enrolled in this study. Thirteen (6.5%) of 200 patients resulted in unfavorable outcome. Four patients (2%) of them underwent posterior decompressive surgery. The main cause of unfavorable outcomes was incomplete decompression of the foraminal stenosis. Unfavorable outcomes were obtained in patients with the level of L5-S1 (p = 0.036), higher body mass index (p = 0.048), higher percentage of slippage (p = 0.024), and severe facet arthropathy (p = 0.013). However, there was no difference in preoperative disc height, foraminal size, facet angle, facet tropism, or preoperative visual analog scale for back and leg pain, the Oswestry disability index, symptom duration, and fusion rate between the two groups. CONCLUSION: Based on these results, posterior decompression and fusion may be considered for obese patients with the level of L5-S1, high-grade spondylolisthesis, or severe facet arthropathy. On the other hand, ALIF can be used an effective alternative treatment in many spinal disorders requiring fusion.

Comparison study of the instrumented circumferential fusion with instrumented anterior lumbar interbody fusion as a surgical procedure for adult low-grade isthmic spondylolisthesis.

BACKGROUND: Instrumented circumferential fusion has been used as a primary and salvage procedure in lumbar spine fusion, especially for adult low-grade isthmic spondylolisthesis. Recently, instrumented anterior lumbar interbody fusion (ALIF) has been shown to provide good clinical and radiologic results that are comparable with those attained with traditional lumbar fusion. However, there have been no reports available that compare instrumented circumferential fusion with instrumented ALIF. METHODS: Between January 2003 and November 2004, a total of 43 consecutive patients underwent instrumented ALIF (group I) at one hospital of the authors. Between February 2003 and October 2006, a total of 32 consecutive patients underwent instrumented circumferential fusion (group II) at the other hospital of the authors. The authors retrospectively reviewed clinical and radiologic data from patients. The time spent on the operation, blood loss, blood transfusions, the length of hospital stay, complications, clinical results, and radiologic results, including disc height (DH), degree of listhesis, segmental lordosis (SL), and whole lumbar lordosis (WL), were analyzed and compared. Clinical outcomes were graded using visual analog scale (VAS) scores. Functional outcomes were measured using Oswestry Disability Index (ODI) scores and return-to-work status. RESULTS: The mean follow-up period was 41.1 and 32.9 months in group I and group II, respectively. Radiologic evidence of fusion was noted in 42 of 43 patients in group I and in 32 of 32 patients in group II. In both groups, all of the radiologic data, including the DH, degree of listhesis, SL, and WL significantly changed from the preoperative to postoperative period except for WL in group II. In both groups, VAS scores for back and leg pain and ODI scores significantly changed from the preoperative to postoperative period. There was no significant difference for VAS scores for back ODI scores in the two treatment groups after surgery. The mean time until return to work was 3.7 months in group I and 3.6 months in group II (p < .05). The mean hospital stay for group I (7.4 days) was shorter than that for group II (15.2 days) (p < .05). The mean operation time in group I (190 minutes) was shorter than that in group II (260.8 minutes) (p < .05). The mean blood loss in group I (300 mL) was less than that in group II (379 mL) (p < .05). CONCLUSIONS: According to the present clinical outcome, instrumented ALIF is at least as effective as instrumented circumferential fusion for the treatment of back pain in adult patients with low-grade isthmic spondylolisthesis. Moreover, in terms of operative data including the duration of operation and hospital stay, as well as blood loss, instrumented ALIF demonstrates better results.

Surgical site infection in spinal surgery: detection and management based on serial C-reactive protein measurements.

OBJECT: C-reactive protein (CRP) is a well-known sensitive laboratory parameter that shows an increase within 6 hours after the onset of bacterial infection. In relation to surgery, a normal CRP response is a rapid increase followed by a gradual reduction, eventually returning to the normal range. The goal of this study was to determine the diagnostic significance of CRP as a detector for early onset surgical site infection in spinal surgery and to discuss effective medical treatment through clinical interpretation and application of the measured CRP values. METHODS: A prospective study was performed in 348 consecutive cases involving patients who underwent spinal surgery under general anesthesia between February and September 2008. Blood samples were obtained preoperatively and on postoperative Days 1, 3, and 5 in patients undergoing single-level decompression surgery. An additional blood specimen was obtained at postoperative Day 7 in patients requiring more extensive surgeries. Recorded laboratory results were compared with the patients' clinical course to determine the diagnostic significance of CRP. All of the patients received intravenous prophylactic antibiotic therapy. Once an abnormal response of CRP, indicated by a tendency toward continuous elevation, was noted on Day 5 or Day 7, the prophylactic antibiotics were replaced with another regimen and administration was resumed along with careful observation for signs of surgical site infection. RESULTS: Monitoring of CRP revealed a characteristic increase and decrease pattern in 332 of 348 patients (95.4%) showing a normal clinical course with regard to early infectious complications. The mean measured CRP (reference range < 4 mg/L) averaged 14.9 +/- 20.3 mg/L on Day 1, 15.4 +/- 25.1 mg/L on Day 3, and 7.9 +/- 13.3 mg/L on Day 5. In contrast, there were 16 cases (4.6%) of abnormal CRP responses resulting in the resumption of intravenous antibiotic treatment, which included a second rise (in 12 cases) and a steady rise (in 4) in the CRP value. Five (1.4%) of 16 patients experienced infectious complications related to spinal surgery. Three patients (0.9%) received long-term antibiotic therapy for 4-6 weeks; however, all patients recovered with medical treatment alone and did not experience gross wound disruption or subsequent discitis. As a predictor for early wound infection, the sensitivity, specificity, positive predictive value, and negative predictive value for abnormal CRP responses were calculated as 100%, 96.8%, 31.3%, and 100%, respectively. CONCLUSIONS: The above results demonstrate that CRP screening is a simple and reliable test for the detection of early infectious complications after spinal surgery. Close observation and appropriate medical management should be performed in a timely fashion when abnormal CRP responses are observed at 5 or 7 days after surgery.

An analysis of general surgery-related complications in a series of 412 minilaparotomic anterior lumbosacral procedures.

OBJECT: Anterior lumbar surgery is associated with certain perioperative visceral and vascular complications. The aim of this study was to document all general surgery-related adverse events and complications following minilaparotomic retroperitoneal lumbar procedures and to discuss strategies for their management or prevention. METHODS: The authors analyzed data obtained in 412 patients who underwent anterior lumbosacral surgery between 2003 and 2005. The series comprised 114 men and 298 women whose mean age was 56 years (range 34-79 years). Preoperative diagnoses were as follows: isthmic spondylolisthesis (32%), degenerative spondylolisthesis (24%), instability/stenosis (15%), degenerative disc disease (15%), failed-back surgery syndrome (7%), and lumbar degenerative kyphosis or scoliosis (7%). A single level was exposed in 264 patients (64%), 2 in 118 (29%), and 3 or 4 in 30 (7%). The average follow-up period was 16 months. RESULTS: Overall, 52 instances of complications and adverse events occurred in 50 patients (12.1%), including sympathetic dysfunction in 25 (6.06%), vascular injury repaired with/without direct suture in 12 (2.9%), ileus lasting > 3 days in 5 (1.2%), pleural effusion in 4 (0.97%), wound dehiscence in 2 (0.49%), symptomatic retroperitoneal hematoma in 2 (0.49%), angina in 1 (0.24%), and bowel laceration in 1 patient (0.24%). There was no instance of retrograde ejaculation in male patients, and most complications had no long-term sequelae. CONCLUSIONS: This report presents a detailed analysis of complications related to anterior lumbar surgery. Although the incidence of complications appears low considering the magnitude of the procedure, surgeons should be aware of these potential complications and their management.

An evaluation of vascular anatomy for minilaparotomic anterior L4-5 procedures.

OBJECT: The complexity of the vascular anatomy pertinent to the L4-5 intervertebral disc space has led to difficulties when performing the anterior approach to the lumbar spine. The purpose of the present study was to evaluate the variations of the great vessels to match the imaging-documented axial anatomy with the surgical exposure. METHODS: The authors analyzed data obtained in 223 patients who had undergone mini-open anterior lumbar surgery involving the L4-5 disc. The preoperative magnetic resonance images or computed tomography scans were evaluated by examiners blinded to the surgical approach to determine the vascular configuration. All complications of the procedures were described. Two major variations of the vascular configuration were delineated according to the location of the bifurcation of the inferior vena cava. On images showing the lower margin of the L-4 vertebra, the anatomy in 182 patients (81%) was classified as Type A because the inferior vena cava (IVC) was not bifurcated; in 38 patients (17%) it was classified as Type B because the IVC was bifurcated. Type A could be subdivided into Types A1 and A2 according to whether the aorta was bifurcated (A2) or not (A1) on the same image. The surgical exposure used was above the bifurcations (in Type A) and below the bifurcations (in Type B). The major complications were three venous injuries, and the leading complication was sympathetic dysfunction in 14 patients, which in most cases resolved spontaneously. CONCLUSIONS: Careful preoperative evaluation of the vascular anatomy is essential to conducting successful anterior lumbar surgery. The determination of an appropriate approach can contribute to a reduction of unnecessary vascular retraction and a consequent decrease in vascular complications.

Revision surgery of the lumbar spine: anterior lumbar interbody fusion followed by percutaneous pedicle screw fixation.

OBJECT: The aim of this study was to evaluate the efficacy of anterior lumbar interbody fusion (ALIF) augmented by percutaneous pedicle screw fixation (PSF) for revision surgery in the lumbar spine and to determine the prognostic factors affecting surgical outcomes. METHODS: The population included 54 consecutively treated patients in whom revision surgery involving ALIF with PSF was performed between 2001 and 2004. There were 22 men and 32 women, whose mean age was 59.5 years (range 25-78 years). The diagnoses prior to revision ALIF were as follows: degenerative disc disease in 25 patients, instability/spondylolisthesis in 15, recurrent disc herniation in seven, and pseudarthrosis in seven. The mean follow-up period was 24 months (range 12-52 months). The mean visual analog scale score for back and leg pain decreased, respectively, from 7.8 to 2.3 and 8.0 to 2.3 (p < 0.001). The mean Oswestry Disability Index score improved from 70 to 25% (p < 0.001). Radiological evidence of fusion was noted in 52 of 54 patients. The mean preoperative segmental lordosis, whole lumbar lordosis, and sacral tilt were 15.2, 35.5, and 28.3 degrees, respectively; these values were significantly increased to 20.4, 40.7, and 31.4degrees, respectively, after revision surgery (p < 0.001). The increase in sacral tilt was positively correlated with improvement in back pain (p = 0.028) and functional status (p = 0.025). CONCLUSIONS: The results demonstrate that ALIF followed by PSF can be an effective alternative in revision surgery of the lumbosacral spine in selected cases. Not only can solid fusion be achieved, sagittal alignment can also be restored in the majority of patients.

Operative failure of percutaneous endoscopic lumbar discectomy: a radiologic analysis of 55 cases.

STUDY DESIGN: A retrospective study. OBJECTIVE: To determine the range of lumbar disc herniation that can be addressed effectively using current endoscopic techniques. SUMMARY OF BACKGROUND DATA: The current technical limitation of the procedure in terms of the location and size of the herniation has not been fully documented in previous studies. METHODS: The inclusion was an intracanal lower lumbar disc herniation in which subsequent surgery was performed because of the presence of remnant fragments. All 1586 cases, including 55 failed cases, were classified according to the size, location, and extent of migration. RESULTS: In the nonmigrated herniations, the central located high-canal compromised (>50%) herniations showed the highest rate of failure (15%), and the rate was significantly different from the low and high-canal compromise group (1.9% and 11.1%, respectively, P < 0.001). There was no significant difference in the failure rate between the nonmigrated herniations and low-grade migration group (2.7% and 3.7%, respectively). However, the high-grade migration group (beyond the measured height of the posterior marginal disc space) showed a significantly high-incidence of failure (15.7%, P < 0.001). CONCLUSIONS: Based on these results, open surgery may be considered for herniations with high-canal compromise and high-grade migration. On the other hand, percutaneous endoscopic lumbar discectomy can be considered to be a surgical option in the remaining intracanal disc herniations.