Clinical Effectiveness of Percutaneous Epidural Neuroplasty According to the Type of Single-Level Lumbar Disc Herniation : A 12-Month Follow-Up Study.

OBJECTIVE: To determine whether the outcomes of percutaneous epidural neuroplasty (PEN) are influenced by the type of lumbar disc herniation (LDH) and evaluate the effectiveness of PEN in patients with single-level LDH. METHODS: This study included 430 consecutive patients with single-level LDH who underwent PEN. Before treatment, the LDH type was categorized as bulging, protrusion, extrusion, and sequestration, while Pfirrmann grades were assigned according to imaging findings. Visual analog scale (VAS) scores for back and leg pain and success rates (Odom's criteria) were assessed at 1, 3, 6, and 12 months after treatment. RESULTS: The mean preoperative VAS scores for back and leg pain were 6.90 and 4.23, respectively; these decreased after PEN as follows : 2.25 and 1.45, respectively, at 1 month; 2.61 and 1.68, respectively, at 3 months; 2.28 and 1.48, respectively, at 6 months; and 2.88 and 1.48, respectively, at 12 months (p<0.001). The decrease in VAS scores for leg pain was significantly greater in the extrusion and sequestration groups than in the other two groups (p<0.05); there were no other significant differences among groups. More than 70% patients exhibited good or excellent 12-month outcomes according to Odom's criteria. Subsequent surgery was required for 59 patients (13.7%), with a significantly higher rate in the extrusion (25.0%) and sequestration (30.0%) groups than in the bulging (7.3%) and protrusion (13.8%) groups (p<0.05). Nevertheless, subsequent surgery was not required for >70% patients with extrusion or sequestration. Patients with Pfirrmann grades 1-3 (14.0-21.5%) showed a significantly higher rate of subsequent surgery than those with Pfirrmann grade 0 (4.9%; p<0.05). CONCLUSION: Our findings suggest that PEN is an effective treatment for back and leg pain caused by single-level LDH, with the outcomes remaining unaffected by the LDH type.

Clinical Significance of Epidurography Contrast Patterns after Adhesiolysis during Lumbar Percutaneous Epidural Neuroplasty.

Background: The correlation between epidurography contrast patterns and the clinical outcomes of percutaneous epidural neuroplasty (PEN) remains unclear. Objective: To analyze the correlation between postadhesiolysis epidurography contrast patterns and the clinical outcomes of patients who undergo lumbar PEN. Design: This study is a retrospective analysis of 78 consecutive patients who underwent lumbar PEN between April 2012 and March 2013. Setting: The analysis was done in the university hospital center. Method: The clinical outcomes of all patients were assessed before and 1, 3, 6, and 12 months after undergoing lumbar PEN. Specifically, the intensity of back and leg pain, quality of life, and procedural outcomes were evaluated using a visual analog scale (VAS), the Oswestry Disability Index (ODI), and the 12-Item Short-Form Health Survey (SF-12). Results: The VAS scores for back and leg pain, ODI score, and SF-12 score exhibited a significant improvement during the follow-up period (P < 0.01 versus preprocedural scores). At most follow-up time points, patients exhibiting extraforaminal contrast distribution (n=22) on postadhesiolysis epidurograms exhibited a similar improvement in VAS scores and a significantly better improvement in ODI and SF-12 scores compared with patients exhibiting intracanal contrast distribution (n=56). Conclusion: Extraforaminal contrast distribution during lumbar PEN may be associated with better functional outcomes.

Efficacy of percutaneous epidural neuroplasty does not correlate with dural sac cross-sectional area in single level disc disease.

PURPOSE: Percutaneous epidural neuroplasty (PEN) is a minimally invasive treatment. The efficacy of PEN has been relatively well investigated; however, the relationship between the clinical effectiveness of PEN and the severity of spinal canal stenosis by disc material has not yet been established. The purpose of this study was to compare clinical outcomes of PEN according to the dural sac cross-sectional area in single level disc disease. MATERIALS AND METHODS: This study included 363 patients with back pain from single level disc disease with and without radiculopathy. Patients were categorized into groups according to spinal canal compromise by disc material: Category 1, less or more than 50%; and Category 2, three subgroups with lesser than a third, between a third and two thirds, and more than two thirds. Clinical outcomes were assessed according to the Visual Analog Scale (VAS) score for back pain and leg pain and Odom's criteria at 1, 3, 6, 12, and 24 months after treatment. RESULTS: The demographic data showed no difference between groups according to spinal canal compromise by disc material except age (older age correlated with more spinal canal compromise). The dural sac cross-sectional area did not correlate with the VAS scores for back and leg pain after PEN in single level disc disease in Groups 1 and 2. Odom's criteria after PEN were also not different according to dural sac cross-sectional area by disc material. CONCLUSION: PEN is an effective procedure in treating single level lumbar disc herniation without affecting dural sac cross-sectional area.

Kyphoplasty versus vertebroplasty: restoration of vertebral body height and correction of kyphotic deformity with special attention to the shape of the fractured vertebrae.

STUDY DESIGN: Retrospective comparative analysis. OBJECTIVE: We analyzed kyphosis correction, vertebral height restoration, and bone cement leakage in patients treated by vertebroplasty (VP) and kyphoplasty (KP) to compare the effectiveness of VP and KP for the treatment of osteoporotic vertebral compression fractures. SUMMARY OF BACKGROUND DATA: Superior results have been reported for the use of KP for kyphotic deformity correction and collapsed vertebral height restoration. However, there are no previous comparative reports comparing the efficacy of KP versus VP according to the shapes of fractured vertebrae. METHODS: A total of 103 patients underwent either VP (n=58) or KP (n=45) for treatment of osteoporotic vertebral compression fracture between October 2006 and September 2009. We organized the patients into 6 groups according to treatment method and fracture type: VP (wedge-shaped), VP (V-shaped), VP (flat-shaped), KP (wedge-shaped), KP (V-shaped), and KP (flat-shaped). Comparisons were performed for kyphosis correction, vertebral height restoration, and cement leakage between VP and KP groups. RESULTS: KP was more effective than VP, especially for middle column height restoration and bone cement leakage prevention, for all fracture types (P value <0.05). In addition, KP was more effective in anterior height restoration and kyphosis correction in both flat and wedge-shape fractures (P value <0.05). However, posterior column vertebral height was not restored in either the KP group or the VP group. The clinical outcomes did not differ between the 2 groups (P value >0.05). CONCLUSIONS: KP has a significant advantage over VP in terms of kyphosis correction, vertebral height restoration, and cement leakage prevention. KP has an obvious advantage in terms of middle vertebral height restoration and cement leakage prevention, especially for V-shape compression fractures.

A novel blasted and grooved low profile pedicle screw able to resist high compression bending loads.

OBJECTIVE: Polyaxial pedicle screws are a safe, useful adjunct to transpedicular fixation. However, the large screw head size can cause soft tissue irritation, high rod positioning, and facet joint injury. However, the mechanical resistance provided by small and low profile pedicle screws is very limited. We therefore developed a novel, low profile pedicle screw using grooving and blasting treatment that is able to resist a high compression bending load. METHODS: We evaluated the compression bending force to displacement and yield loads for seven different screw head types that differed with regard to their groove intervals and whether or not they had been blasted. RESULTS: The rank order of screw types that had the greatest compression bending force to displacement was as follows: (1) universal polyaxial, (2) low polyaxial with 0.1mm grooves and blasting, (3) low polyaxial with blasting, (4) low polyaxial with 0.15mm grooves and blasting, (5) low polyaxial with 0.05mm grooves and blasting, (6) low polyaxial with 0.05mm grooves, (7) and low polyaxial. Low polyaxial screws with 0.1mm grooves and blasting had the maximum yield load and highest compression bending force to displacement of all seven polyaxial screw head systems evaluated. CONCLUSION: Blasting and grooving treatment of pedicle screw heads resulted in screw heads with a high yield load and compression bending force relative to displacement because of increased friction. Low polyaxial pedicle screws with 0.1 mm grooves treated by blasting have mechanical characteristics similar to those of universal polyaxial pedicle screws.

Spinal surgery in patients with end-stage renal disease undergoing hemodialysis therapy.

STUDY DESIGN: Case series retrospective review. OBJECTIVE: To present the surgical treatment guideline for spinal diseases with end-stage renal disease (ESRD) patients undergoing hemodialysis. SUMMARY OF BACKGROUND DATA: Treatment for spinal diseases with ESRD patients in is a special clinical challenge because of complex medical and clinical problems. METHODS: We retrospectively reviewed 12 patients who underwent spinal surgeries among patients with chronic renal failure at our hospital from May 2000 to September 2007. The medical records and radiologic findings for these patients were reviewed and concomitant medical diseases, laboratory findings, pre- and postoperative care, clinical outcomes, and complications were investigated. RESULTS: One patient died of pneumonia and sepsis 2 months after fusion surgery. Other postoperative complications included postoperative delirium in 3 patients and terminal ileitis and delayed primary spondylodiscitis in 1 patient each. There were no postoperative wound infections associated with the spinal surgery.The preoperative mean visual analogue scale score was 7.9 +/- 0.61, which improved to 2.2 +/- 1.25 at the time of final follow-up for 11 patients. Among 5 patients who underwent fusion surgery, solid bone fusion was achieved in only 3 patients and included those who underwent posterior lumbar interbody fusion with pedicle screw fixation. In 2 patients who underwent posterior lumbar interbody fusion with cage alone, solid fusion was not achieved. In 1 of 2 patients who underwent anterior cervical fusion with plating, solid fusion was achieved. The overall fusion rate was 57.1% in patients with ESRD undergoing hemodialysis. CONCLUSION: Spinal surgeries in ESRD patients undergoing hemodialysis can be performed with acceptable outcomes; however, the complication rates and mortality rates are relatively high and the fusion rate is low. To obtain a better outcome, multiple factors such as comorbid medical diseases, laboratory abnormalities, and osteoporosis should be carefully considered.

Magnetic resonance imaging findings of subsequent fractures after vertebroplasty.

OBJECTIVE: The biomechanical effect of injected cement has been considered as the cause of adjacent vertebral fracture (AVF) after vertebroplasty, but the clinical evidence supporting this hypothesis is still insufficient. METHODS: We retrospectively reviewed 33 patients with subsequent fractures among 278 patients who underwent percutaneous vertebroplasty at our hospital from January 2002 to December 2005. The bone marrow edema pattern of subsequent fractures on magnetic resonance imaging was analyzed in 33 patients. In addition, the relationship between the location and distribution pattern of inserted cement and site of subsequent fractures was investigated. RESULTS: Among 33 subsequent fractures, we found 13 cranial AVFs, 7 caudal AVFs, and 13 remote fractures. The incidence rate of AVFs was 7.3% of 273 patients. Among 33 subsequent vertebral fractures, 13 were cranial AVFs (Group 1), 3 were superior, 7 were inferior, and 3 were overall (23.1%, 53.8%, and 23.1%, respectively). Of 7 caudal AVFs (Group 2), 7 were superior (100%). In 13 remote fractures (Group 3), 10 were superior, 1 was inferior, 2 were overall (76.9%, 7.7%, and 15.4%, respectively). In AVFs, bone marrow edema appeared mainly toward injected cement (P = 0.005). When injected cement made a solid mass rather than interdigitation, the occurrence rate of cranial AVFs was high (P = 0.004). CONCLUSION: Bone marrow edema of AVFs appeared significantly toward the previous injected cement. This phenomenon supports the idea that the biomechanical effect of injected cement is one of the causative factors which affect the occurrence of AVF after percutaneous vertebroplasty. In particular, when injected cement forms a solid mass rather than interdigitation, the risk of cranial AVF may increase.

Percutaneous vertebroplasty for the treatment of osteoporotic burst fractures.

BACKGROUND: Vertebroplasty is a minimally invasive surgical procedure which involves injecting polymethylmethacrylate into the compressed vertebral body. At present the indications include the treatment of osteoporotic compression fractures, vertebral myeloma, and metastases. The value of vertebroplasty in osteoporotic compression fracture has been discussed comprehensively. The surgical operation for burst fractures without neurological deficit remains controversial. Some authors have asserted that vertebroplasty is contraindicated in patients with burst fracture. However, we performed the procedure, after considering the patents general condition, to reduce surgical risks and the duration of immobilisation. The purpose of this study is to investigate clinical outcomes, kyphosis correction, wedge angle, and height restoration of thoraco-lumbar osteoporotic burst fractures treated by percutaneous vertebroplasty. MATERIALS AND METHODS: Twenty-five patients with osteoporotic burst fracture were treated with postural reduction followed by vertebroplasty. We measured the kyphosis, wedge angle, spinal canal compromise and the height of the fractured vertebral body initially, after postural reduction, and after vertebroplasty. FINDINGS: The average height of the collapsed vertebral bodies was 24.8% of the original height. Average kyphosis angle was 19.4 degrees and average wedge angle was 19.8 degrees at first. Mean canal encroachment was initially 25.1%. Kyphosis angle, wedge angle, and anterior, middle, and posterior height improved significantly after the procedure. The mean amelioration of the spinal canal encroachment after vertebroplasty was 23.3%. The average increase in anterior vertebral body height was 7.5 mm, central was 5.8 mm, and posterior was 0.9 mm. The mean reduction in kyphosis angle was 6.8 degrees and the mean reduction in wedge angle was 9.7 degrees . CONCLUSION: Although vertebroplasty has been considered as contraindicated in thoraco-lumbar burst fractures, we successfully used the procedure as a safe treatment in patients with osteoporotic burst fracture without neurologic deficit. This method could eliminate the need for and risks of major spinal surgery. We would like to offer it as a relatively safe and effective methods of management in thoraco-lumbar burst fractures.

Clinical approach and surgical strategy for spinal diseases in pregnant women: a report of ten cases.

STUDY DESIGN: Case series retrospective review. OBJECTIVE: To present the treatment guideline for spinal diseases in pregnant women. SUMMARY OF BACKGROUND DATA: Treatment for spinal diseases in pregnant women is a special clinical challenge because of complex medical and surgical clinical problems. METHODS: We retrospectively reviewed 10 patients who underwent surgery for spinal diseases, who were diagnosed during pregnancy at our hospital from February 1992 to October 2005. Six patients had herniated lumbar discs, 3 patients had spinal tumors, and 1 patient had spinal tuberculosis. RESULTS: Five patients with HLDs underwent partial hemilaminectomy and discectomy during pregnancy and maintained the pregnancy. One patient underwent posterior lumbar interbody fusion and had a therapeutic abortion 6 days after lumbar surgery. In 1 patient with hemangioblastoma at the level of T8-T9 level, prepartum surgery was performed maintaining pregnancy in gestational age, 29 weeks. In another patient with hemangioblastoma at the T10 level, a preoperative cesarean section and tumor removal surgery were performed under the same anesthesia in gestational age 34 weeks. One patient had recurrent intramedullary ependymoma at the C3-T2 level. She had the preterm baby by vaginal delivery before spinal operation in gestational age 33 weeks and underwent tumor removal surgery. One patient with tuberculous spondylitis at the level of T3-T5 level, therapeutic abortion performed in gestational age, 16 weeks because of inevitable radiation exposure during fusion surgery. CONCLUSION: In most spinal diseases, including HLD and tumors, prepartum surgical treatment can be safely performed maintaining pregnancy. For patients with progressive neurologic deficit at 34 to 36 weeks gestation or later, spine surgery should be performed following the induction of delivery or a cesarean section, or at the same time.

Contributing factors affecting the prognosis surgical outcome for thoracic OLF.

The thoracic ossification of ligamentum flavum (OLF) is a disease that produces spastic paraparesis, and there are various factors that may affect the surgical outcome of thoracic OLF patients. The authors of this study treated 19 of these thoracic OLF patients from 1998 to 2002, and retrospectively reviewed the patients' age, sex, symptom duration, involved disease level, preoperative clinical features, neurological findings, radiological findings, the other combined spinal diseases and the surgical outcomes. There were excellent or good surgical outcomes in 16 patients, but 3 patients did not improve after thoracic OLF surgery: this included 1 patient, whose motor function worsened after decompressive thoracic OLF surgery. The favorable contributing factors of surgical outcome in thoracic OLF are a short preoperative symptom duration, single-level lesion, and unilateral lesion type on CT axial scan. On the contrary, the poor prognostic factors are beak type lesion and intramedullary signal changes on T(2)-weighted sagittal MRI. The complete preoperative evaluation including radiologic findings will provide valuable aid in presuming the surgical outcome for the thoracic OLF patients.

Surgical treatments for lumbar disc disease in adolescent patients; chemonucleolysis / microsurgical discectomy/ PLIF with cages.

The herniated lumbar disc (HLD) in adolescent patients is characterized by typical discogenic pain that originates from a soft herniated disc. It is frequently related to back trauma, and sometimes it is also combined with a degenerative process and a bony spur such as posterior Schmorl's node. Chemonucleolysis is an excellent minimally invasive treatment having these criteria: leg pain rather than back pain, severe limitation on the straight leg raising test (SLRT), and soft disc protrusion on computed tomography (CT). Microsurgical discectomy is useful in the cases of extruded or sequestered HLD and lateral recess stenosis due to bony spur because the nerve root is not decompressed with chymopapain. Spinal fusion, like as PLIF, should be considered in the cases of severe disc degeneration, instability, and stenosis due to posterior central bony spur. In our study, 185 adolescent patients, whose follow-up period was more than 1 year (the range was 1-4 years), underwent spinal surgery due to HLD from March, 1998 to December, 2002 at our institute. Among these cases, we performed chemonucleolysis in 65 cases, microsurgical discectomy in 94 cases, and posterior lumbar interbody fusion (PLIF) with cages in 33 cases including 7 reoperation cases. The clinical success rate was 91% for chemonucleolysis, 95% for microsurgical disectomy, and 89% for PLIF with cages, and there were no non- union cases for the PLIF patients with cages. In adolescent HLD, chemonucleolysis was the 1st choice of treatment because the soft adolescent HLD was effectively treated with chemonucleolysis, especially when the patient satisfied the chemonucleolysis indications.

Football injuries at Asian tournaments.

PURPOSE: To examine the incidences and patterns of injuries that required medical attention among Asian football players. METHODS: A total of 411 Asian football players at both senior and youth (U-20) elite levels were observed during 50 international matches. Independent injury observers and team doctors determined the occurrence of injuries and recorded the location, type, time, and circumstances of the injuries using a protocol sheet. RESULTS: The overall injury frequency rate was 45.8 out of 1000 hours. As the tournaments progressed into the knockout stages, the incidence and severity of the injuries increased. The most common sites of injuries were the knees (18.5%), lower legs (17.3%), and ankles (14.2%). Although most injuries were diagnosed as contusions, the more serious injuries were those diagnosed as sprains (especially concerning the knee and ankle) or strains (thigh and back). CONCLUSIONS: The incidences of injuries to Asian football players were higher than those to European players, but the patterns of the injuries showed no major differences. CLINICAL RELEVANCE: To develop an injury-prevention program, more solid and comprehensive data need to be collected to identify the risk factors and variables associated with higher incidences of injuries to Asian football players.

Glutamine synthetase induced spinal seizures in rats.

Glutamine synthetase (GS) is a key enzyme in the regulation of glutamate neurotransmission in the central nervous system. It is responsible for converting glutamate to glutamine, consuming one ATP and NH3 in the process. Glutamate is neurotoxic when it accumulates in extracellular fluids. We investigated the effects of GS in both a spinal cord injury (SCI) model and normal rats. 0.1-ml of low (2- micro M) and high (55- micro M) concentrations of GS were applied, intrathecally, to the spinal cord of rats under pentobarbital anesthesia. Immediately after an intrathecal injection into the L1-L3 space, the rats developed convulsive movements. These movements initially consisted of myoclonic twitches of the paravertebral muscles close to the injection site, repeated tonic and clonic contractions and extensions of the hind limbs (hind limb seizures) that spread to the fore limbs, and finally rotational axial movements of the body. An EMG of the paravertebral muscles, fore and hind limbs, showed the extent of the muscle activities. GS (2- micro M) caused spinal seizures in the rats after the SCI, and GS (6- micro M) produced seizures in the uninjured anesthetized rats. Denatured GS (70 degrees C, 1 hour) also produced spinal seizures, although higher concentrations were required. We suggest that GS may be directly blocking the release of GABA, or the receptors, in the spinal cord.