Ambulation and survival following surgery in elderly patients with metastatic epidural spinal cord compression.

BACKGROUND AND CONTEXT: Metastatic epidural spinal cord compression (MESCC) is a disabling consequence of disease progression. Surgery can restore or preserve physical function, improving access to treatments that increase duration of survival; however, advanced patient age may deter oncologists and surgeons from considering surgical management. PURPOSE: Evaluate the duration of ambulation and survival in elderly patients following surgical decompression of MESCC. STUDY DESIGN/SETTING: Retrospective file review of a prospective database, under institutional review board (IRB) waiver of informed consent, of consecutive patients treated in an academic tertiary care medical center from August 2008 to March 2015. PATIENT SAMPLE: Patients ≥65 years presenting neurological and/or radiological signs of cord compression because of metastatic disease, who underwent surgical decompression. OUTCOME MEASURES: Duration of ambulation and survival. METHODS: Patients underwent urgent multidisciplinary evaluation and surgery. Ambulation and survival were compared with age, pre-, and postoperative neurological (American Spinal Injury Association [ASIA] Impairment Scale [AIS]) and performance status (Karnofsky Performance Status [KPS]), and Tokuhashi Score using Kruskal-Wallis and Wilcoxon signed rank tests, Pearson correlation coefficient, Cox regression model, log-rank analysis, and Kaplan-Meier analysis. RESULTS: Forty patients were included (21 male, 54%; mean age 74 years, range 65-87). Surgery was performed a mean 3.8 days after onset of motor symptoms. Mean duration of ambulation and survival were 474 (range 0-1662) and 525 days (range 11-1662), respectively; 53% of patients (21 of 40) survived and 43% (17 of 40) retained ambulation for ≥1 year. There was no significant relationship between survival and ambulation for patients aged 65-69, 70-79, or 80-89 years, although Kaplan-Meier analysis suggested stratification. There was a significant relationship between duration of ambulation and pre- and postoperative AIS (p=.0342, p=.0358, respectively) and postoperative KPS (p=.0221). Tokuhashi score was not significantly related to duration of survival or ambulation, and greatly underestimated life expectancy in 22 of 37 (59%) patients with scores 0-11. CONCLUSIONS: Decompressive surgery led to marked improvement in neurological function and performance status. More than 50% of patients survived for >1 year, some for 3 years or more after surgery.

Canal expansive laminoplasty in the management of cervical spondylotic myelopathy.

BACKGROUND: Cervical spondylotic myelopathy is often progressive and leads to motor and sensory impairments in the arms and legs. Canal expansive laminoplasty was initially described in Japan as an alternative to the traditional laminectomy approach. The results of this approach have not previously been described in the Israeli population. OBJECTIVES: To describe the technique of CEL and present our clinical results in the management of patients with CSM due to multilevel compressive disease. METHODS: All patients undergoing CEL during the period 1984-2000 were identified. Of these, 24 of 25 patients had complete clinical information. Mean follow-up was 18 months (range 4-48). Mean age was 60 years (range 45-72). One patient underwent CEL at three levels, 22 patients at four to five levels and 1 patient at six levels The primary outcome measure was improvement in spinal cord function (according to the Nurick classification). RESULTS: Twenty-three (96%) of the patients experienced relief of their symptoms. Of these, 11 patients showed improvement in their Nurick grade, 12 patients were unchanged and one had worsening. Intraoperative complications (epidural bleeding and dural tear) occurred in six patients. Two patients developed a late kyphosis. CONCLUSIONS: Our treatment of choice for multilevel CSM is canal expansive laminoplasty as initially described by Hirabayashi. It provides the ability for posterior surgical decompression without compromising the mechanical stability of the spine. This approach has the benefit of not requiring internal fixation and fusion. Our clinical outcome and surgical complication rate are comparable to those in the literature.

Mini-open thoracoscopically assisted thoracotomy versus video-assisted thoracoscopic surgery for anterior release in thoracic scoliosis and kyphosis: a comparison of operative and radiographic results.

BACKGROUND CONTEXT: Combining anterior release and interbody fusion with posterior instrumented fusion is an accepted treatment for severe rigid spinal deformity. Video-assisted thoracoscopic surgery (VATS) and mini-open thoracoscopically assisted thoracotomy (MOTA) are two minimally invasive approaches to the thoracic spine. Both reduce surgical trauma, improve cosmesis and provide effective exposure for release and fusion. Published data and the authors' surgical experience have demonstrated that both techniques are equivalent in degree of release to traditional open thoracotomy, but no comparison between these two minimally invasive alternatives has been published to our knowledge. PURPOSE: This study compared MOTA and VATS under the hypothesis that both result in similar corrections and comparable operative parameters when used in conjunction with posterior instrumented fusion. STUDY DESIGN/SETTING: Retrospective chart review of consecutive case series by two surgeons. PATIENT SAMPLE: Twenty-one (13 female, 8 male) patients underwent MOTA and 24 patients (17 female, 7 male) underwent VATS for anterior release, discectomy and fusion prior to posterior instrumented fusion. OUTCOME MEASURES: Outcomes were measured at a minimum of 1-year follow-up and included radiographic Cobb measurements and operative parameters. METHODS: The indications for surgery included rigid and severe scoliosis or thoracic kyphosis. Data collection included preoperative demographics, number of levels released, primary curve correction, operative time and blood loss. Data were normalized per number of levels released anteriorly. Statistical analysis of results was done using a two-sample t test assuming equal variances with two-tail p values less than .05. RESULTS: More anterior levels were operated on average in the VATS group (6.33 vs. 4.38 levels). Curve correction per anterior level released was similar in both groups (8.7 and 8.8 degrees/level for MOTA and VATS, respectively). There was a significant difference in operative time with MOTA averaging 131.7 minutes and VATS averaging 162.8 minutes. However, a comparison of the operative time per anterior level operated, approached statistical significance in favor of VATS (33.0 vs. 28.4 minutes, p=.08). There was no significant difference in estimated blood loss during the anterior portion of the surgeries. There was a trend toward decreased blood loss per operated level favoring VATS (68.4 vs. 38.9 cc, p=.09). CONCLUSIONS: Both approaches resulted in corrections that compare favorably with open thoracotomy. We suggest that a factor in choosing between these two minimally invasive techniques is the number of thoracic levels requiring release. For four levels or less, MOTA provides an excellent alternative to standard thoracotomy. For five or more levels, VATS provides for excellent exposure of additional levels with the advantages of less operative time and blood loss per operated level.

The effect of end screw orientation on the stability of anterior instrumentation in cyclic lateral bending.

BACKGROUND CONTEXT: Screw pullout at the proximal or distal end of multilevel anterior instrumentation can occur clinically. Previous laboratory studies have shown that angulation of vertebral body screws increases screw pullout strength and stability in toggling. PURPOSE: To determine the effect of end screw angulation on instrumentation construct stability after cyclic, lateral bending. STUDY DESIGN: A biomechanical study in calf spines comparing two anterior spinal instrumentation constructs, one with parallel polyaxial screws and the other with angled polyaxial end screws. METHODS: Sixteen instrumented constructs were made from eight thoracic (T8-T12) and eight lumbar calf spines (L1-L5). Eight (four lumbar specimens and four thoracic specimens) had five bicortical screws inserted mid-body and parallel to the end plates. The other eight specimens had two screws angled toward the superior end plates of the top two vertebrae; the middle vertebra had a mid-body screw parallel to the end plate, and the bottom two vertebrae had screws angled towards their inferior end plates. The constructs were then cycled in lateral bending, and the displacements of the two instrumentations with a 10 N-m bending load were compared. RESULTS: After 10,000 cycles, constructs with parallel end screws exhibited twice the average displacement than those with angled screws: 5.4 mm versus 2.9 mm (p=.031). CONCLUSION: The use of angled screws at the ends of anterior constructs demonstrated increased construct stability after cycling compared with traditional transverse screws. Although angled screw insertion is technically more difficult and is possible only with specific screw designs, its use might increase instrumentation longevity.

Murine spinal fusion induced by engineered mesenchymal stem cells that conditionally express bone morphogenetic protein-2.

OBJECT: The authors hypothesized that spinal fusion can be achieved and monitored by using cell-mediated gene therapy. Mesenchymal stem cells (MSCs) genetically engineered to express recombinant human bone morphogenetic protein-2 (rhBMP-2) conditionally, were implanted into the paraspinal muscles of mice to establish spinal fusion. The goal was to demonstrate an MSC-based gene therapy platform in which controlled gene expression is used to obtain spinal fusion in a murine model. METHODS: Mesenchymal stem cells expressing the rhBMP-2 gene were injected into the paravertebral muscle in mice. Bone formation in the paraspinal region was longitudinally followed by performing micro-computerized tomography scanning, histological studies, and an analysis of osteocalcin expression to demonstrate the presence of engrafted engineered MSCs. The minimal period of rhBMP-2 expression by the engineered MSCs required to induce fusion was determined. The results of this study demonstrate that genetically engineered MSCs induce bone formation in areas adjacent to and touching the posterior elements of the spine. This newly formed bone fuses the spine, as demonstrated by radiological and histological studies. The authors demonstrate that injected cells induce active osteogenesis at the site of implantation for up to 4 weeks postinjection. They found that a 7-day induction of rhBMP-2 expression in genetically engineered MSCs was sufficient to form new bone tissue, although the quantity of this bone increased as longer expression periods were implemented. CONCLUSIONS: After their injection genetically engineered MSCs can efficiently form new bone in the paraspinal muscle of the mouse to obtain spinal fusion. The extent and quantity of this newly formed bone can be monitored by controlling the duration of rhBMP-2 gene expression.

Preoperative embolization of hypervascular spinal tumors: current practice and center experience.

Preoperative transarterial embolization of hypervascular spinal tumors has been extensively used, and is considered to be a highly effective adjuvant technique in reducing intraoperative blood loss during surgery. Moreover, it has been reported to increase the feasibility and safety of the surgical procedure, leading to better surgical outcomes. We review the English literature in an attempt to identify indications, appropriate timing of embolization in relation to surgery, technical aspects of the procedure, complications, and the contribution of embolization to the surgical management of spinal tumors. In addition, we report our experience with embolization of hypervascular metastases.

Robot-assisted vertebral body augmentation: a radiation reduction tool.

STUDY DESIGN: Retrospective. OBJECTIVE: To assess radiation exposure time during robot-guided vertebral body augmentation compared with other published findings. SUMMARY OF BACKGROUND DATA: Rising incidence of vertebral compression fractures in the aging population result in widespread use of vertebral body cement augmentation with significant radiation exposure to the surgeon, operating room staff, and patient. Radiation exposure leads to higher cancer rates among orthopedic and spine surgeons and patients. METHODS: Thirty-three patients with 60 vertebral compression fractures underwent robot-guided vertebral body augmentation performed by 2 surgeons simultaneously injecting cement at 2 levels under pulsed fluoroscopy. The age of patients was in the range from 29 to 92 (mean, 67 yr). One to 6 vertebrae were augmented per case (average 2). Twenty-five patients had osteoporotic fractures and 8 had pathological fractures. Robotic guidance data included execution rate, accuracy of guidance, total surgical time, and time required for robotic guidance. Radiation-related data included the average preoperative computed tomographic effective dose, radiation time for calibration, registration, placement of Kirschner wires, and total procedure radiation time. Radiation time per level and surgeon's exposure were calculated. RESULTS: Kyphoplasty was performed in 15 patients (1 sacroplasty), vertebroplasty in 13, and intravertebral expanding implants in 5. The average preoperative computed tomographic effective dose was 50 mSv (18-81). Average operative time was 118 minutes (49-350). Mean robotic guidance took 36 minutes. Average operative radiation time was 46.1 seconds per level (33-160). Average exposure time of the surgeons and the operating room staff per augmented level was 37.6 seconds. The execution rate was 99%, with an accuracy of 99%. Two complications (hemothorax and superficial wound infection) occurred. CONCLUSION: The radiation exposure of the surgeon and the operating room staff in a series of robot-assisted vertebral body augmentation was 74% lower than published results on fluoroscopy guidance and approximately 50% lower than the literature on navigated augmentation. LEVEL OF EVIDENCE: 4.

Symptomatic facet cysts of the subaxial cervical spine.

Subaxial cervical facet cysts are uncommon. We report two patients with intraspinal, extradural, subaxial cervical spinal facet cysts, and review the literature to describe the epidemiology, clinical presentation, imaging findings, and treatment options for these lesions. Intraspinal, extradural, cervical spinal cysts should be considered as part of the differential diagnosis in patients presenting with clinical signs of cervical radiculopathy or myelopathy.

Cauda equina syndrome after spinal epidural steroid injection into an unrecognized paraganglioma.

OBJECTIVE: Clinically significant spinal hemorrhage is an extremely rare but potentially devastating complication of spinal epidural steroid injection. We report a rare case of cauda equina syndrome after spinal epidural injection that inadvertently penetrated an unrecognized spinal paraganglioma. METHODS: The clinical records for a patient presenting with cauda equina syndrome were retrospectively reviewed. A literature search was performed to identify reports of cauda equina syndrome in patients undergoing spinal epidural steroid injection, as well as recent large series describing complications associated with these injections. CASE REPORT: A 37-year-old man presented to our emergency department with severe low back pain radiating bilaterally to the lower extremities and urinary incontinence. His pain had greatly intensified 1 day after spinal epidural steroid injection. He had a 1-year history of low back pain diagnosed as disk herniation and managed conservatively but had experienced recent onset of a similar pain and new onset of nocturnal back pain causing sleep disturbance. Epidural injection had been administered based on the earlier diagnosis of disk herniation. Examination using magnetic resonance imaging revealed a previously unrecognized oval hemorrhagic mass lesion at L2-3, which had been inadvertently penetrated during epidural injection. Emergent en bloc resection resolved the patient's neurological symptoms. At histopathologic analysis, the tumor was diagnosed as a spinal paraganglioma. DISCUSSION: The presented case indicates the importance of a thorough history, physical examination, and imaging assessment before spinal epidural steroid injection.

Vertebral augmentation in the treatment of vertebral compression fractures: review and new insights from recent studies.

Vertebral compression fractures (VCF) due to osteoporotic degeneration and metastatic disease represent an increasingly significant public health problem. Percutaneous vertebroplasty (VP) began as a simple, low-cost procedure that aimed to provide pain relief for patients with VCF. Balloon kyphoplasty (KP) was introduced later, and was presented not only as a "pain killer," but also as a deformity correction procedure. The preponderance of evidence has shown that vertebral augmentation provides significant and sustained clinical benefit for patients with VCF. The debate raised by studies published in the New England Journal of Medicine comparing VP with a sham procedure highlights the importance of very careful patient selection for vertebral augmentation procedures, since osteoporotic VCF is usually a self-limiting condition. However, vertebral augmentation may be beneficial in patients with comorbidities that make prolonged bed rest dangerous, in patients with fractures that fail to heal, and in patients with painful VCF due to metastatic disease. Patient selection should be based on a combination of clinical and radiological indications. We review recent studies in the extensive literature on vertebral augmentation, with the goal of clarifying some of the controversy surrounding these procedures.

Long-term outcome of surgical correction of congenital kyphosis in patients with myelomeningocele (MMC) with segmental spino-pelvic fixation.

STUDY DESIGN: A retrospective case series of patients with myelomeningocele (MMC) who underwent kyphectomy and posterior segmental fixation using Luque rods and 16-gauge wires. OBJECTIVE: To assess outcomes after posterior kyphectomy and segmental fixation for kyphosis in patients with MMC. METHODS: Thirteen consecutive patients who underwent posterior kyphectomy for transforaminal fixation contiguous to "everted lamina." Fusion rates, time to fusion, change in Cobb angle, complications, and improvement in activities of daily living using the Katz score were measured. RESULTS: Average age at time of surgery was 9.2 (range, 4.5-17) years. Average time to follow-up was 120 (range, 20-310) months. Solid fusion was achieved in 9 patients (69%) with a mean time to fusion of 12 months. The mean postoperative kyphotic curve was 22° with an average correction of 90°. Five patients (38%) experienced a postoperative complication. The mean improvement in activities of daily living score was 1.6 points and all patients achieved independent sitting balance. CONCLUSION: Segmental spino-pelvic fixation is a solid alternative mode of fixation in patients with MMC with congenital kyphosis. Patient selection, proper perioperative multidisciplinary assessment, and surgeons' expertise are significant in the success of this complex surgery.METHODS evaluation and class of evidence (CoE)STUDY DESIGN: Prospective cohort Retrospective cohort Case control Case series•METHODS Patients at similar point in course of treatment• Follow-up ≥ 85%• Similarity of treatment protocols for patient groups• Patients followed-up long enough for outcomes to occur Control for extraneous risk factorsOverall class of evidenceIVThe definiton of the different classes of evidence is available on page 63.

A hard fall: an isolated fracture of lumbarized S1 spinous process: a case report and review of the literature.

STUDY DESIGN: A case of an isolated lumbarized S1 spinous process fracture due to direct trauma from a fall on the lower back is reported here. The patient was treated nonoperatively. Pain subsided and he returned to every day. OBJECTIVE: To alert physicians of this rare fracture as part of the differential diagnosis in cases of direct trauma to the lower spine. The method of diagnosing such pathology and its treatment are described. SUMMARY OF BACKGROUND DATA: A 22-year-old man was admitted with lower back pain after falling down a flight of stairs during which, he sustained a direct blow to his lower back. The patient had a scrape over L5-S1 area and midline tenderness around the L5-S1 area. He was neurologically intact. Radiographs revealed a lumbarized S1 vertebra and an isolated fracture of the spinous process of S1. The fracture resulted from the direct trauma to the S1 lumbarized vertebrae. The direct trauma and the fact that the patient has a lumbarized S1 vertebra with a thin spinous process contributed to the fragility of the spinous process. METHODS: Nonoperative measures, physical therapy, primarily analgesics, and local heat, were employed. RESULTS: The patient returned to his normal routine after 3 weeks. CONCLUSIONS: Few cases of isolated spinous process fractures have been described, and, to our knowledge, this is the first reported case of an isolated fracture of a lumbarized S1 spinous process to due to direct trauma. Radiograph imaging was adequate to determine the extent of the injury. Nonoperative treatment can allow the patient to return to every day life without the need of surgery.

Spine injuries are common among asymptomatic patients after gunshot wounds.

BACKGROUND: Spine injuries after gunshot wounds are thought to be rare among asymptomatic patients. The occurrence of spine injuries among asymptomatic patients with gunshot wounds was studied to determine the necessity for mandatory spine immobilization and radiographic imaging. METHODS: In this retrospective cohort study, initial physical examination, radiographic findings, and final diagnosis and treatment were reviewed. Patients were included if they were admitted to the authors' level 1 trauma center with gunshot wounds to the head, neck, or trunk during a 10-year period. Spine injuries were considered "significant" if the injury was associated with spinal cord injury or required spine-related surgical procedures or prolonged spine immobilization. Spine injuries were defined as "unsuspected" if there were no neurologic findings at admission. RESULTS: During the study period, 2,450 patients who survived more than 24 hours were admitted with gunshot wounds to the trunk, neck, or head. Of these patients, 244 (approximately 10%) had spine injuries, and 228 of them had complete records. Two thirds of the spine injuries were found to be significant, requiring surgery or prolonged immobilization, and 13% were unsuspected. CONCLUSIONS: Spine injuries without neurologic signs are not uncommon among patients with gunshot wounds. Complete radiographic spine imaging is therefore recommended to ensure that spine injuries are not missed in this population.

Correlation between pre-employment screening X-ray finding of spondylolysis and sickness absenteeism due to low back pain among policemen of the Israeli police force.

STUDY DESIGN: A historical prospective case/control study of the significance and correlation between pre-employment findings of L5-S1 spondylolysis and sickness absenteeism due to low back pain among police officers. OBJECTIVES: Examining the importance of pre-employment lumbar spine radiographs as a prediction of work absenteeism. SUMMARY OF BACKGROUND DATA: Spondylolysis is a defect in the pars interarticularis. Its etiology remains controversial, it is a common condition among young athletes, and it carries genetic predisposition. Although described mostly as an incidental radiographic finding in the adult population, spondylolysis is implicated as a contributing factor to low back pain, although the cause-and-effect relation is not clear. METHODS: One hundred and sixty-nine police officers with L5-S1 spondylolysis were identified out of 3988 examined. Incidence density of sickness absenteeism due to low back pain was calculated for the patients and the controls. The Cox's proportional hazard model was used for comparison between the two groups, controlling for possible confounding variables. RESULTS: Similar incidence of sickness absenteeism due to low back pain was found among the patients and controls. The total duration of sickness absenteeism, however, was 2.7 times higher in the spondylolysis group than the controls. Prevalence of spondylolysis is origin specific, denoting genetic predisposition to this condition. Total sickness absenteeism not related to low back pain was not significantly different between the two study groups. CONCLUSIONS: There is low predictive value of pre-employment lumbar spine radiograph as a screening tool predicting sickness absenteeism due to low back pain. Spondylolysis, however, may increase the duration of sickness absenteeism in patients with low back pain.