Amir A. Mehbod

Can c7 plumbline and gravity line predict health related quality of life in adult scoliosis

Study Design. This study prospectively evaluated the health related quality of life (HRQOL) of 73 adults presenting with scoliosis at a single institution, as related to their spinal (C7 plumbline) and global (gravity line) balance. Objective. To assess the influence of sagittal and coronal balance on HRQOL in adult scoliosis. Summary of Background Data. Many surgeons believe that achieving adequate spinal balance is important in the management of adult spinal deformity, but the evidence supporting this concept remains limited. A previous study has found weak correlations between sagittal spinal balance and HRQOL in adult spinal deformity, but this finding has never been confirmed independently. In addition, although the use of the gravity line is gaining interest in the evaluation of global balance, it remains unknown if this parameter is associated with HRQOL. Methods. During a 1-year period, 73 consecutive new patients presenting with unoperated adult scoliosis and requiring full spine standing radiographs were evaluated using a force plate in order to simultaneously assess the gravity line. All patients also completed the Oswestry Disability Index (ODI) questionnaire to assess the HRQOL. Spinal balance was evaluated from the C7 plumbline and global balance from the gravity line, respectively. C7 plumbline and gravity line were both assessed with respect to the posterosuperior corner of the S1 vertebral body and central sacral vertebral line in the sagittal and coronal plane, respectively. C7 plumbline and gravity line, as well as their relative position, were correlated with the ODI, using Spearman coefficients. Results. Sagittal spinal (C7 plumbline) and global (gravity line) balance, as well as their relative position were significantly related to the ODI. A poor ODI (>34) was associated with a sagittal C7 plumbline greater than 6 cm, a sagittal gravity line greater than 6 cm, and a C7 plumbline in front of the gravity line. Correlations between coronal balance and the ODI were not statistically significant. Conclusion. Sagittal spinal and global balance was strongly related to the ODI in adults with scoliosis. The observed correlation coefficients were higher than those reported in the only previous study suggesting the detrimental association of positive sagittal balance on ODI in adult spinal deformity. Coronal spinal and global balance did not influence the ODI in the current study cohort. Thisstudy underlines the relevance of C7 plumbline and gravity line in the evaluation of spinal and global balance, and lends further support to the philosophy of achieving adequate sagittal balance in the management of adult spinal deformity, especially in patients older than 50 years old with degenerative scoliosis.

A correlation of radiographic and functional measurements in adult degenerative scoliosis.

Study Design. Retrospective functional and radiographic analysis of symptomatic patients with de novo degenerative lumbar and thoracolumbar scoliosis. Objective. To evaluate the radiographic parameters of symptomatic patients presenting with de novo degenerative adult scoliosis and correlate them with functional scores. Summary of Background Data. Previous studies have been inconclusive as to the correlation of radiographic parameters and clinical symptomatology. Methods. Radiographic analysis of 58 consecutive symptomatic patients with de novo degenerative lumbar and thoracolumbar scoliosis was performed using posteroanterior and lateral 36-inch standing radiographs. Measurements included curve type, curve location, curve magnitude, coronal alignment, sagittal alignment, and anteroposterior and lateral intervertebral olisthesis. Clinical functional data were measured with Oswestry Disability Index, Roland-Morris Disability Questionnaire, and RAND 36-item Health Survey questionnaire. Correlation between clinical data and radiographic data were then calculated. Results. Sagittal balance did not show significant correlation with functional results. However, coronal imbalance (more than 5 cm from midsacrum) affected physical function (P = 0.028) and outcomes (P > 0.05). Also, moderate to severe lateral olisthesis (equal or more than 6 mm) demonstrated higher bodily pain then mild lateral olisthesis (P = 0.005). Good lumbar lordosis correlated positively with health assessment as reflected in SF-36 score (P = 0.039, r = 0.291). Conclusion. Reduced lumbar lordosis and increased lumbosacral scoliosis can affect the general health status of older patients with de novo degenerative scoliosis. Lateral olisthesis, mainly, and anteroposterior olisthesis are important elements of rotatory subluxation in the lumbar curves, which are important radiographic parameters, predicting symptomatology and health status of patients with de novo degenerative scoliosis.

Surgical treatment for the painful motion segment: matching technology with the indications: posterior lumbar fusion.

Study Design. A convenience literature-based review of the different techniques of posterior lumbar fusion. Objective. To describe the history, specific techniques, and outcomes of different methods of posterior lumbar fusion. The specific methods that were described include 1) uninstrumented posterior, posterolateral, and facet fusion, and 2) instrumented fusion using pedicle screws or facet screws. Summary of Background Data. There are various posterior fusion techniques available for the treatment of degenerative lumbar spine conditions. Each individual technique has specific technical demands, indications, advantages, and disadvantages which should be taken into consideration when performing these procedures. Methods. The published scientific literature on the different methods of posterior lumbar fusion was reviewed. The history, indications, advantages, disadvantages, and clinical and radiographic outcomes were described based on the literature search. Results/Conclusions. Posterior fusion techniques have been and will continue to be among the most commonly performed procedures in lumbar spine surgery. The different methods of fusion are well defined, as are the possible complications and outcomes. They are effective techniques when performed on appropriately selected patients by a surgeon knowledgeable in the techniques and indications. Further studies are needed regarding promising but relatively unproven developments such as minimally invasive surgery and the use of osteoinductive agents.

Prospective study of postoperative lumbar epidural hematoma: incidence and risk factors.

Study Design. Prospective clinical series. Objective. To determine the incidence, volume, and extent of postoperative epidural hematoma resulting in thecal sac compression, and to identify risk factors correlated with measured hematoma volumes. Summary of Background Data. Risk factors for postoperative hematoma development have been retrospectively determined in small populations of symptomatic patients. A prospective study of hematoma characteristics and associated risk factors in a consecutive series of patients could significantly enhance our understanding of postoperative hematoma. Methods. Preoperative magnetic resonance imaging and clinical data on 13 pre- and intraoperative risk factors were prospectively collected on 50 consecutive patients undergoing lumbar decompression surgery with or without fusion. Postoperative magnetic resonance imagings were performed within 2 to 5 days of surgery. Thecal sac cross-sectional area was calculated at each disc space. Relative thecal sac compression due to hematoma was calculated at all levels where postoperative cross-sectional area was smaller than preoperative. Hematoma volumes were calculated. Multivariate analysis identified risk factors associated with postoperative hematoma volume. Results. After decompression, 58% of patients developed epidural hematoma of sufficient magnitude to compress the thecal sac beyond its preoperative state at one or more levels. None developed new postoperative neurologic deficits. A mean of 1.4 levels were decompressed. Hematoma extended over a mean of 1.9 levels. Maximal thecal sac compression due to hematoma occurred at an adjacent, nondecompressed level in 28% of patients. Multivariate analysis found age greater than 60, multilevel procedures, and preoperative international normalized ratio to be associated with larger hematoma volumes. Conclusion. Lumbar decompression surgery results in a 58% incidence of asymptomatic compressive postoperative epidural hematoma. Adjacent level compression by hematoma occurs in 28% of patients. Advanced age, multilevel procedures, and international normalized ratio are independently associated with postoperative hematoma volume.

Surgical outcomes of decompression, decompression with limited fusion, and decompression with full curve fusion for degenerative scoliosis with radiculopathy.

Study Design. A retrospective clinical cohort study at a single spine center of patients with degenerative scoliosis and radiculopathy severe enough to require surgery. Objective. To evaluate the functional outcomes of 3 surgeries for degenerative scoliosis with radiculopathy; decompression alone, decompression and limited fusion, and decompression and full curve fusion. Summary of Background Data. Although these 3 surgical treatments have all been described for this problem, there exists little information as to what outcomes to expect. Methods. The study cohort consisted of 85 patients who met the inclusion criteria of degenerative scoliosis and radiculopathy, who had undergone 1 of the above 3 surgeries, who had not had any previous lumbar spine surgery, who had a minimum follow-up of at least 2 years, and who had filled out preoperative and postoperative functional evaluation forms including SF-36, Oswestry Disability Index, Roland Morris Scores, and a satisfaction questionnaire. Logistic regression analysis was conducted to predict the likelihood of success as related to decompression alone of rotatory olisthetic segments, extent of fusion, and postoperative sagittal balance. Patient demographics including curve magnitude, operative blood loss, length of hospital stay, complications, and need for revision surgeries were analyzed. The patients having decompression alone had the highest mean age (76.4 years) compared to decompression and limited fusion (70.4), and decompression and full curve fusion (62.5). Results. Cobb scoliosis angles remained unchanged in the 2 groups not having full curve fusion, while the full curve fusion group changed from a mean 39° before surgery to 19° at follow-up. The complication rate was highest (56%) in the full fusion group, was 40% in the limited fusion group, and 10% in the decompression alone group. The overall SF-36 analysis showed significant improvement in bodily pain, social function, role emotional, mental health, and mental composite domains. Oswestry Disability Indexes improved significantly in the decompression alone and limited fusion groups, but not in the full fusion group. In contrast, the satisfaction questionnaire showed the highest success to be in the full-curve fusion group and the lowest in the decompression-only group. Regression analysis revealed that sacrum to curve apex fusions and positive postoperative sagittal imbalance were associated with poor outcomes. Conclusion. Both good and poor results were seen with each of the 3 procedures.

Degenerative Lumbar Scoliosis : Radiographic Correlation of Lateral Rotatory Olisthesis With Neural Canal Dimensions

Study Design. A radiographic review of 78 consecutive patients with degenerative rotatory lumbar scoliosis. Objective. To assess the correlation between rotary olisthesis and neural canal dimensions using radiographic indexes and to establish a gradation system of lateral rotatory olisthesis. Summary of Background Data. Degenerative scoliosis is a three-dimensional deformity often associated with spinal stenosis, although the association is not well defined. Methods. A total of 78 consecutive patients (average age, 69 years) with de novo degenerative scoliosis (79% lumbar, 21% thoracolumbar; average curve, 25°) were studied with plain radiographs and MRI at presentation. Radiographic measurements included lateral translation, anteroposterior olisthesis, Cobb angle, and intervertebral rotation (Nash-Moe grade difference). Computerized measurements of MRI included dural sac cross-sectional area and anteroposterior diameter, minimum subarticular height, and foramen cross-sectional area bilaterally (convexity and concavity). Measurements were conducted twice on each lumbar level (total, 312) and the average was recorded. Results. Lateral translation 5 mm or less (Grade I) was associated with Nash-Moe change 0 (23%) or I (77%), lateral translation 6–10 mm (Grade II) was coupled with Nash-Moe change 0 (20%) or I (80%) and lateral deviation more than 11 mm (Grade III) was associated with I (76%) or II (24%) Nash-Moe change. Maximum intervertebral rotation tended to be at either L2–L3 (48%) or L3–L4 (39%). Increased lateral translation was associated with increased intervertebral rotation (r = 0.37, P < 0.001). Increased anteroposterior olisthesis was associated with decreased anteroposterior diameter (r = −0.18, P < 0.001) and cross-sectional area (r = −0.11, P < 0.05) of the dural sac. Larger segmental Cobb angles were associated with greater foraminal cross-sectional area in the convexity (r = 0.12, P < 0.05). In the concavity, there was no significant correlation (P > 0.05) between indexes of rotary olisthesis and foraminal area or subarticular height. Cross-sectional foraminal area and subarticular height were significantly larger in the convexity than in the concavity of the scoliotic levels. Conclusions. In degenerative scoliotic curves, lateral translation is associated with rotation. Increased rotary olisthesis does not lead to decreased dural sac area. Anteroposterior olisthesis is inversely correlated to the dural sac anteroposterior diameter and cross-sectional area. With increased segmental Cobb angle, foraminal cross-sectional area enlarges in the convexity and does not decrease in the concavity. Presence of intervertebral rotation alone does not appear to be associated with reduced neural canal dimensions. Ligamentum flavum hypertrophy, posterior disc bulging, and bony overgrowth are more likely to contribute to stenosis irrespective of scoliosis.

Clinical and radiological outcome of anterior-posterior fusion versus transforaminal lumbar interbody fusion for symptomatic disc degeneration: a retrospective comparative study of 133 patients

Abundant data are available for direct anterior/posterior spine fusion (APF) and some for transforaminal lumbar interbody fusion (TLIF), but only few studies from one institution compares the two techniques. One-hundred and thirty-three patients were retrospectively analyzed, 68 having APF and 65 having TLIF. All patients had symptomatic disc degeneration of the lumbar spine. Only those with one or two-level surgeries were included. Clinical chart and radiologic reviews were done, fusion solidity assessed, and functional outcomes determined by pre- and postoperative SF-36 and postoperative Oswestry Disability Index (ODI), and a satisfaction questionnaire. The minimum follow-up was 24 months. The mean operating room time and hospital length of stay were less in the TLIF group. The blood loss was slightly less in the TLIF group (409 vs. 480 cc.). Intra-operative complications were higher in the APF group, mostly due to vein lacerations in the anterior retroperitoneal approach. Postoperative complications were higher in the TLIF group due to graft material extruding against the nerve root or wound drainage. The pseudarthrosis rate was statistically equal (APF 17.6% and TLIF 23.1%) and was higher than most published reports. Significant improvements were noted in both groups for the SF-36 questionnaires. The mean ODI scores at follow-up were 33.5 for the APF and 39.5 for the TLIF group. The patient satisfaction rate was equal for the two groups.

Evidence-based Medicine Analysis of Isthmic Spondylolisthesis Treatment Including Reduction versus Fusion in Situ for High-grade Slips

Study Design. Literature review. Objectives. The purpose of this article is to review the available literature and to attempt to formulate evidence-based recommendations for the surgical treatment of high-grade spondylolisthesis in the pediatric population. Summary of Background Data. The surgical management of high-grade spondylolisthesis remains controversial due to the lack of high level evidence. Prospective randomized studies have not been completed. Methods. Through an electronic database search and published literature cross-reference, appropriate studies were identified and assigned the appropriate level of evidence. Results. There were no Level I or II evidence on this topic with our search. The best level of evidence that we have on this topic is retrospective comparative studies. We found 5 such articles which compared fusion in situ to reduction and fusion for high-grade spondylolisthesis. Pseudarthrosis rates are decreased by performing an instrumented reduction with a fusion. However, there is no significant difference in a clinical outcome of patients treated in situ versus reduction. Conclusion. Because of the paucity of high levels of evidence, we are not able to formulate clear guidelines for treatment of high-grade spondylolisthesis based on the best evidence available in the published literature.

The Assessment of Intraobserver and Interobserver Error in the Measurement of Noncongenital Scoliosis in Children * 10 Years of Age

Study Design. Retrospective review of scoliosis radiographs. Objectives. To determine measurement variability in children ≤ 10 years of age with noncongenital scoliosis. Summary of Background Data. Measurement variability in congenital and adolescent idiopathic scoliosis has been studied. There is no study of measurement variability in young children with noncongenital scoliosis. Methods. A retrospective review of children ≤ 10 years of age followed for noncongenital scoliosis was performed. End vertebrae were identified on radiographs, and the curves were measured (Cobb method) twice by each of six observers. The same soft lead pencil and goniometer was used. Intraobserver and interobserver variability for continuous data was determined. Results. There were 64 children. The diagnosis was infantile/juvenile idiopathic scoliosis in 42, neuromuscular scoliosis in 7, scoliosis associated with mesenchymal disorders or other syndromes in 12, and unknown in 3 children. The curve was thoracic in 54, thoracolumbar in 8, and lumbar in 2. There were 19 left and 45 right curves. The average age was 6.6 ± 2.6 years. There were a total of 768 Cobb angle measurements with an average Cobb angle of 38 ± 22° (range, 10°–115°). Intraobserver variability was ± 6°; interobserver variability was ± 7°. Conclusion. In children ≤10 years of age with noncongenital scoliosis, intraobserver measurement variability in Cobb angle measurement is ± 6° and interobserver variability is ±7°. To be certain that there is a significant difference between Cobb angle measurements in children with noncongenital scoliosis and ≤ 10 years of age there must be a change of at least ±7°.

Therapy of spinal wound infections using vacuum-assisted wound closure: risk factors leading to resistance to treatment.

Study Design This study retrospectively reviewed spine surgical procedures complicated by wound infection and managed by a protocol including the use of vacuum-assisted wound closure (VAC). Objective To define factors influencing the number of debridements needed before the final wound closure by applying VAC for patients with postoperative spinal wound infections. Summary of Background Data VAC has been suggested as a safe and probably effective method for the treatment of spinal wound infections. The risk factors for infection resistance and need for debridement revisions after VAC placement are unknown. Methods Seventy-three consecutive patients with 79 wound infections after undergoing spine surgery were studied (6 of them had recurrence of infection). All patients were taken to the operating room for irrigation and debridement under general anesthesia followed by placement of the VAC with subsequent delayed closure of the wound. Linear regression and t test were used to identify if the following variables were risk factors for the resistance of infection to VAC treatment: timing of clinical appearance of infection, depth of infection (deep or superficial), presence of instrumentation, positive culture for methicillin-resistant Staphylococcus aureus (MRSA) or more than 1 microorganism, age of the patient, and presence of other comorbidities. Results There were 34 males and 39 females with an average age of 58.4 years (21 to 82). Once the VAC was initiated, there was an average of 1.4 procedures until and including closure of the wound. The wound was closed an average of 7 days (range 5 to 14) after the placement of the initial VAC on the wound. The average follow-up was 14 months (range 12 to 28). All of the patients but 2 achieved a clean, closed wound without removal of instrumentation at a minimum follow-up of 1 year. Sixty patients had implants (instrumentation or allograft) within the site of wound infection. Thirteen patients had a decompression with exposed dura. Sixty-four infections (81%) presented with a draining wound within the first 6 weeks postoperatively. Sixty-nine infections (87.3%) were deep below the fascia. There was no statistical significance (P>0.05) of all tested risk factors for the resistance of infection to treatment with the VAC system. The parameter more related to repeat VAC procedures was the culture of MRSA or multiple bacteria. Conclusions VAC therapy may be an effective adjunct in closing spinal wounds even after the repeat procedures. The MRSA or multibacterial infections seem to be most likely to need repeat debridements and VAC treatment before final wound closure.