Previous Spine Research Articles

Prognostic Factors for Satisfaction After Decompression Surgery for Lumbar Spinal Stenosis.

Surgical treatment for lumbar spinal stenosis is associated with both short- and long-term benefits with improvements in patient function and pain. Even though most patients are satisfied postoperatively, some studies report that up to one-third of patients are dissatisfied. To present clinical outcome data and identify prognostic factors related to patient satisfaction 1 yr after posterior decompression surgery for lumbar spinal stenosis. This multicenter register study included 2562 patients. Patients were treated with various types of posterior decompression. Patients with previous spine surgery or concomitant fusion were excluded. Patient satisfaction was analyzed for associations with age, sex, body mass index, smoking status, duration of pain, number of decompressed vertebral levels, comorbidities, and patient-reported outcome measures, which were used to quantify the effect of the surgical intervention. At 1-yr follow-up, 62.4% of patients were satisfied but 15.1% reported dissatisfaction. The satisfied patients showed significantly greater improvement in all outcome measures compared to the dissatisfied patients. The outcome scores for the dissatisfied patients were relatively unchanged or worse compared to baseline. Association was seen between dissatisfaction, duration of leg pain, smoking status, and patient comorbidities. Patients with good walking capacity at baseline were less prone to be dissatisfied compared to patients with poor walking capacity. This study found smoking, long duration of leg pain, and cancerous and neurological disease to be associated with patient dissatisfaction, whereas good walking capacity at baseline was positively associated with satisfaction after 1 yr.

Ewing Sarcoma of the Spine: Prognostic Variables for Survival and Local Control in Surgically Treated Patients.

Multicenter, ambispective observational study. To quantify mortality and local recurrence after surgical treatment of spinal Ewing sarcoma (ES) and to determine whether an Enneking appropriate procedure and surgical margins (en bloc resection with wide/marginal margins) are associated with improved prognosis. Treatment of primary ES of the spine is complex. Ambiguity remains regarding the role and optimal type of surgery in the treatment of spinal ES. The AOSpine Knowledge Forum Tumor developed a multicenter database including demographics, diagnosis, treatment, mortality, and recurrence rate data for spinal ES. Patients were stratified based on surgical margins and Enneking appropriateness. Survival and recurrence were analyzed using Kaplan-Meier curves and log-rank tests. Fifty-eight patients diagnosed with primary spinal ES underwent surgery. Enneking appropriateness of surgery was known for 55 patients; 24 (44%) treated Enneking appropriately (EA) and 31 (56%) treated Enneking inappropriately (EI). A statistically significant difference in favor of EA-treated patients was found with regards to survival (P = 0.034). Neoadjuvant and postoperative chemotherapy was significantly associated with increased survival (P = 0.008). Local recurrence occurred in 22% (N = 5) of patients with an EA procedure versus 38% (N = 11) of patients with an EI procedure. The timing of chemotherapy treatment was significantly different between the Enneking cohorts (P < 0.001) and all EA-treated patients received chemotherapy treatment. Although, local recurrence was not significantly different between Enneking cohorts (P = 0.140), intralesional surgical margins and patients who received a previous spine tumor operation were associated with increased local recurrence (P = 0.025 and P = 0.018, respectively). Surgery should be undertaken when an en bloc resection with wide/marginal margins is feasible. An EA surgery correlates with improved survival, but the impact of other prognostic factors needs to be evaluated. En bloc resection with wide/marginal margins is associated with local control. 3.

Growth pattern change of a benign clear cell ‘sugar’ tumor of the lung: Serial imaging surveillance over seven years

Clear cell tumor of the lung is a rare benign mesenchymal tumor and only sporadic cases have been previously reported. The present study reports the case of a 58-year-old man who presented with an incidentally detected solitary pulmonary nodule. Based on comparisons with serial previous chest and spine radiographs, a growth pattern change in the nodule (initial gradual growth over 4.5 years, then recent no growth over 2.5 years) was identified. The nodule was diagnosed as a benign clear cell tumor of the lung (CCTL) following surgical resection. Few studies have previously reported interval growth of CCTLs and the growth pattern of CCTL is not yet well known. To the best of our knowledge, this is the first reported case in which the growth pattern change of CCTL was identified via serial imaging over 7 years of follow-up.

Artrodese lombar intersomática anterior multinível combinada com estabilização posterior em discopatia – Análise clínico‐funcional prospectiva

ObjectiveThis was a prospective controlled study in patients with lumbar degenerative disc disease submitted to instrumented anterior lumbar interbody fusion combined with posterior stabilization. MethodsSample with 64 consecutive patients operated by the same surgeons over four years. Half of the anterior lumbar interbody fusion were at two levels, 43.8% at three levels, and 6.25% at one level. The authors stand‐alone interbody cages with integrated screws, filled with bone matrix and bone morphogenetic protein 2. ResultsHalf of the sample had previous lumbar spine surgeries, 75% had associated degenerative listhesis, and 62.5% had posterior lumbar compression disease. Approximately 56% of the sample had at least one nonunion risk factor. The Oswestry index changed from 71.81 ± 7.22 at the preoperative assessment to 24.75 ± 7.82 at the final follow‐up evaluation, while the visual analog pain scale changed from 7.88 ± 0.70 to 2.44 ± 0.87 (p < 0.001). Clinical and functional improvements were better according to the intervention performed in a higher number of levels, proving multilevel anterior lumbar interbody fusion efficacy, which was performed in 93.75% of the sample. The global complication rate was 7.82%, and the major complications rate was 0%. No cases of non‐union were observed. ConclusionInstrumented anterior lumbar interbody fusion combined with posterior stabilization is a successful option for uni‐ and multilevel degenerative disc disease of L3 to S1, even in significant presence of the risk factors of nonunion and previous lumbar surgeries, guarantying very satisfactory clinical functional and radiographic outcomes, with a low complications rate over the medium term.

Health-Related Quality of Life in Early-Onset Scoliosis Patients Treated Surgically: EOSQ Scores in Traditional Growing Rod Versus Magnetically Controlled Growing Rods.

Cross-sectional study. To compare quality of life and caregiver burden in traditional growing rod (TGR) and magnetic controlled growing rods (MCGR) patients. MCGR decrease surgical sessions associated with treatment of early onset scoliosis (EOS), hoping to minimize the burdens seen with repetitive invasive surgeries in TGR treatment. Although the clinical indications for these treatments have largely been agreed upon, there is a lack of understanding of their impact on patients' and families' quality of life. Inclusion criteria: ≤10 years of age at index procedure, major curve ≥30°, no previous spine surgery, minimum 1-year postoperative follow-up. The previously validated 24-item early onset scoliosis questionnaire (EOSQ-24) was utilized to assess quality of life. Statistic methods were applied to compare domain scores between TGR and MCGR patients. Forty-four children with EOS were enrolled; 25 TGR and 19 MCGR. Groups were similar in sex and age at index surgery. Age at time of questionnaire and mean length of follow-up were significantly different; patients were older (14.0 vs. 8.8 yr) and had longer follow-up (101.3 vs. 34.3 mo) in TGR (P < 0.01). Deformity correction and complication rates were similar between groups. At the time of questionnaire, scores of economic burden and overall satisfaction in MCGR were significantly superior to those in TGR by univariate analysis. When controlled for duration of follow-up, some domain scores trended towards statistical significance, some remained stable, and others regressed to non-significance. Health related quality of life data reveal superior outcomes in overall satisfaction and financial burden domains in the MCGR group. However, the positive effects of MCGR decrease when controlled for length of follow up, indicating that the MCGR is not yet a magic fix-all, and that the TGR remains an option in the treatment of EOS. 3.

Cervical sagittal balance parameters after single-level anterior cervical discectomy and fusion: Correlations with clinical and functional outcomes.

Background:Normal sagittal cervical alignment has been associated with improved outcome after anterior cervical discectomy and fusion (ACDF).Objective:The aim of this study is to identify alterations of cervical sagittal balance parameters after single-level ACDF and assess correlations with postoperative functionality.Methods:A retrospective chart review was performed between January 2010 and January 2014 to identify adult patients with no previous cervical spine surgery who underwent ACDF at any one level between C2 and C7 for the single-level degenerative disease. Tumor, infection, and trauma cases were excluded from the study. For the included cases, the following data were recorded preoperatively and 6 months–1 year after surgery: sagittal balance-marker measurements of the C1–C2 angle, C2–C7 angle, C7 slope, segmental angle at the operated level, and sagittal vertical axis (SVA) distance between C2 and C7, as well as the neck disability index and visual analog scale of pain.Results:The present study included 47 patients (average age: 51.2 years; range: 28–86 years). A moderate negative correlation between a smaller C2–C7 angle and the presence of right arm pain before treatment was found (P = 0.0281). Postoperatively, functionality scores significantly improved in all patients. C1–C2 angle increased with statistical significance (P = 0.0255). C2–C7 angle, segmental angle, C7 slope, and SVA C2–C7 distance did not change with statistical significance after surgery. C7 slope significantly correlated with overall cervical sagittal balance (P < 0.05).Conclusions:Single-level ACDF significantly increases upper cervical lordosis (C1–C2) without significantly changing lower cervical lordosis (C2–C7). The C7 slope is a significant marker of overall cervical sagittal alignment (P < 0.05).

Rectal Necrosis: A Rare Complication of Palliative Radiotherapy for Sacral Spine Metastasis

Radiation proctocolitis is a common side effect of radiation therapy. In rare cases, chronic radiation injury can be severe enough to cause rectal necrosis. In this study, a case of rectal necrosis after sacral spine radiotherapy was presented. Anterior rectal wall necrosis and rectovaginal fistula is thought to be rare, severe and challenging rectal long-term complication of the previous sacral spine irradiation. Although, rectovaginal fistula which resulted in intractable rectal bleeding seems to be a rare side-effect of radiotherapy, physicians must not forget about this complication, as it can be fatal in patients who often have been cured of cancer. © 2018, Journal of Clinical and Diagnostic Research. All rights reserved.

A comparative study between interlaminar nerve root targeted epidural versus infraneural transforaminal epidural steroids for treatment of intervertebral disc herniation.

Background:Low back pain (LBP) is one of the most common musculoskeletal abnormalities. Epidural corticosteroid injections (ESIs) have been used long time ago for treatment of lumbar radiculopathy or discogenic back pain in case of failed medical and conservative management. Different techniques for ESIs include the interlaminar, the caudal, and the transforaminal approaches.Purpose:The aim of our study is to compare between the efficacy of infraneural transforaminal ESI and lumbar paramedian nerve root targeted interlaminar steroid injection in reduction of unilateral radicular pain secondary to disc prolapse.Patients and Methods:This prospective double-blind randomized study was performed on 40 patients randomized into two equal groups, each of 20: the infraneural transforaminal ESI (IN group) and the interlaminar parasagittal ESI (IL group). Patients with backache without leg radiation, or with focal motor neurological deficit, previous spine surgery, S1 radiculopathy, lumbar ESI in the past month, systemic steroid used recently within 4 weeks before the procedure, allergy to any medication or addiction to opioids, and pregnancy were excluded from the study. The duration and efficacy of pain relief (defined as ≥40% reduction of pain perception) by 0–10 visual analog scale (VAS) is the primary outcome. Functional assessment using Modified Oswestry Disability Questionnaire (MODQ) and possible side effects and complications are the secondary outcomes.Results:The VAS and MODQ scores were significantly lower in both groups in comparison with the basal values. There was also a lower VAS in the infraneural group than the parasagittal (IL) group up to 6 months after injection.Conclusion:The infraneural (IN) epidural steroid is more favorable than the parasagittal (IL) interlaminar epidural steroid owing to its long-term improvement in physical function than the parasagittal technique with no serious side effects.

Non-surgical improvement of cervical lordosis is possible in advanced spinal osteoarthritis: a CBP® case report.

[Purpose] To present a case of the non-surgical improvement in cervical kyphosis in a patient with history of cervical spine trauma and advanced osteoarthritis. [Subject and Methods] A 38 year old male presented with a chief complaint of chronic neck pain that was not substantially relieved by recent previous traditional physiotherapy and chiropractic manipulation. The cervical radiograph demonstrated a cervical hypolordosis of 5° as measured by the Harrison posterior tangent method from C2–C7. There was a 15° kyphosis at C4–C6 with advanced degenerative changes consistent with previous spine trauma. The patient was treated by CBP® methods incorporating cervical extension traction, extension exercises, and spinal manipulation for 30 sessions over an 18 week period. [Results] After the treatment sessions, there was a substantial (27°) increase in global C2–C7 lordosis, and 5° decrease in C4–C6 degenerative kyphosis corresponding to the reduction in neck pain and disability, and an improvement in overall health status as indicated on the SF-36 health questionnaire. [Conclusion] Although degenerative spondylosis of the cervical spine will have physical limitations to non-surgical correction, this case serves as an example that it is possible to reduce degenerative kyphosis and increase global cervical lordosis corresponding to health improvements in these patients.

Biomechanical tolerance of whole lumbar spines in straightened posture subjected to axial acceleration.

Quantification of biomechanical tolerance is necessary for injury prediction and protection of vehicular occupants. This study experimentally quantified lumbar spine axial tolerance during accelerative environments simulating a variety of military and civilian scenarios. Intact human lumbar spines (T12-L5) were dynamically loaded using a custom-built drop tower. Twenty-three specimens were tested at sub-failure and failure levels consisting of peak axial forces between 2.6 and 7.9 kN and corresponding peak accelerations between 7 and 57 g. Military aircraft ejection and helicopter crashes fall within these high axial acceleration ranges. Testing was stopped following injury detection. Both peak force and acceleration were significant (p < 0.0001) injury predictors. Injury probability curves using parametric survival analysis were created for peak acceleration and peak force. Fifty-percent probability of injury (95%CI) for force and acceleration were 4.5 (3.9-5.2 kN), and 16 (13-19 g). A majority of injuries affected the L1 spinal level. Peak axial forces and accelerations were greater for specimens that sustained multiple injuries or injuries at L2-L5 spinal levels. In general, force-based tolerance was consistent with previous shorter-segment lumbar spine testing (3-5 vertebrae), although studies incorporating isolated vertebral bodies reported higher tolerance attributable to a different injury mechanism involving structural failure of the cortical shell. This study identified novel outcomes with regard to injury patterns, wherein more violent exposures produced more injuries in the caudal lumbar spine. This caudal migration was likely attributable to increased injury tolerance at lower lumbar spinal levels and a faster inertial mass recruitment process for high rate load application. Published 2017. This article is a U.S. Government work and is in the public domain in the USA. J Orthop Res 36:1747-1756, 2018.

Does Patients' Perception of Leg Length After Total Hip Arthroplasty Correlate With Anatomical Leg Length?

BackgroundThis study assessed the correlation among the patients' perception of the leg length discrepancy (LLD) after total hip arthroplasty (THA) and the anatomical and functional leg length, pelvic and knee alignments, and foot height. MethodsPatients without significant spinal pathology or previous spine or lower extremity surgery who underwent primary THA (101 patients) were evaluated using EOS images obtained in standing position. All 3-dimensional measures were evaluated and compared for the repeatability and reproducibility and correlation with patients' perception of leg length. ResultsIn our study, the anatomical femoral length (odds ratio [OR] 0.9, P = .732) did not correlate with patients' perception of the LLD, but other variables like the distance from the middle of the tibial plafond to ground (OR 14.3, P = .003), sagittal knee alignment (OR 1.07, P = .021), and pelvic obliquity (OR 1.05, P = .021) were correlated with the patients’ perception of LLD. ConclusionThe LLD is a multifactorial complication. We found that the anatomical femoral length as the factor that can be modified with THA technique or choice of prosthesis is not the only important factor. We recommend comprehensive physical examination to investigate spinal deformities, pelvic obliquity, abductor muscle weakness, sagittal and coronal knee alignment, and foot deformity in patients who complain of LLD after THA.

THE RELATIONSHIP BETWEEN SEGMENTAL ROLLING ABILITY AND LUMBAR MULTIFIDUS ACTIVATION TIME

Segmental rolling has been utilized as an assessment and intervention tool to identify and affect dysfunction of the upper quarter, core, and lower quarter. One theory to explain dysfunctional segmental rolling is a lack of segmental spinal control / stabilization. Faulty muscle firing sequencing has been related to poor spinal stability, however to date, no assessment tool exists to evaluate a patient's motor coordination of local and global musculature. The purpose of this study was to assess the temporal sequence of lumbar multifidus activation associated with anterior deltoid activation, and to determine if faulty sequencing was associated with the inability to segmentally roll in subjects without mobility restrictions. The authors hypothesized that in individuals who could not roll, a multifidus muscle onset latency relative to a prime mover activation would be present. In addition, a subset of the individuals with an inability to roll were utilized for a pilot study examining the ability to address the firing pattern with corrective exercise. Twenty healthy subjects (13 females, 7 males), ages 19-25, participated in the study. Each subject underwent an upper and lower quarter screen and assessment of thoracic spine mobility. Subjects were excluded from the study if they had previous spine surgery, or were currently experiencing back pain. In addition, subjects who had any disease, disorders, or pathology that would hinder participation in segmental rolling or who had spinal movement contraindications were excluded. Since shoulder flexion is performed during the study, participants who had shoulder pathology or contraindications to upper extremity movement were excluded as well. Subjects with less than 50 degrees of trunk rotation were excluded from the study due to a possible physical mobility limitation that would prevent proficient segmental rolling. Included subjects were assessed on their ability to segmentally roll. Subjects who could complete the rolling task were placed in cohort A ("can roll"), and subjects who could not roll were placed in cohort B ("can't roll").Electromyographic (EMG) activity of the multifidus was recorded adjacent to the lamina of the L4 vertebrae using intramuscular fine-wire electrodes. EMG activity of the anterior deltoid was also recorded with a surface electrode during a single arm movement into shoulder flexion. While in a standing position, subjects were instructed to move their right upper arm into flexion as quickly as possible. Subjects flexed their shoulder to 90 degrees for three trials while muscle activity was recorded. Data were high-pass filtered at 30 Hz to remove baseline artifact, and the onset EMG times was selected as the point at which EMG increased two SD above baseline levels. Onset of the multifidus muscle was reported relative to that of the prime mover (anterior deltoid). Muscle onset latency was defined as the time difference between the onset of contraction of the multifidus and the anterior deltoid. Nine subjects were placed in cohort A, 11 subjects were placed in cohort B. The mean firing time of the lumbar multifidus for the cohort A was 16.67msec before the anterior deltoid, and the mean firing time of the lumbar multifidus for cohort B was 57.36msec after the anterior deltoid. There was a statistically significant difference (p<0.00) in the firing time between cohorts A and B. In subjects who could segmentally roll, the multifidus muscle activation always preceded that of the prime mover muscle activation. In subjects who could not segmentally roll, the results of this study confirm that there is a multifidus muscle onset latency relative to the activation of the anterior deltoid. The inability to segmentally roll may be related to faulty sequencing of lumbar multifidus firing.

Patients' beliefs about diagnosis and treatment of cervical spondylosis with radiculopathy.

The clinical results of surgical spine care may be influenced by the patients' understanding and knowledge of his or her condition, treatment options and decision-making process. The aim of this survey study was to evaluate certain beliefs and opinions of patients with a degenerative condition in the cervical spine with a history of cervical radiculopathy such as importance of magnetic resonance imaging, risk factors, treatment alternatives and effectiveness. An anonymous questionnaire survey was performed on two different patient populations with a degenerative condition in the cervical spine with a history of cervical radiculopathy referred to the outpatients' clinics of two neurosurgical departments in Germany and Norway. The survey consisted of seven questions: four questions about the respondents' gender and age, history of previous spine surgery and/or conservative treatment for cervical disorder and three questions regarding the importance of imaging in the decision-making process, patients' willingness to undergo cervical surgery based on imaging findings even with few or no symptoms and the effectiveness of surgical or conservative treatment. Two hundred eleven patients answered the questionnaire. Sixty-seven percent of all patients with a degenerative cervical condition believe that results from MRI studies are more important than clinical findings. Forty-seven percent were willing to undergo surgery based on MRI showing abnormalities even without or having few symptoms. Fifty percent believe that surgery is more effective in the treatment of axial neck pain. Misbeliefs and misconceptions exist concerning certain aspects of the diagnosis and management in patients with degenerative conditions in the cervical spine with a history of cervical radiculopathy in a large proportion of patients referred to neurosurgical outpatient clinics.

Understanding the value of minimally invasive procedures for the treatment of lumbar spinal stenosis: the case of interspinous spacer devices

Background ContextMinimally invasive lumbar spinal stenosis procedures have uncertain long-term value. PurposeThis study sought to characterize factors affecting the long-term cost-effectiveness of such procedures using interspinous spacer devices (“spacers”) relative to decompression surgery as a case study. Study DesignModel-based cost-effectiveness analysis. Patient SampleThe Medicare Provider Analysis and Review database for the years 2005–2009 was used to model a group of 65-year-old patients with spinal stenosis who had no previous spine surgery and no contraindications to decompression surgery. Outcome MeasuresCosts, quality-adjusted life years (QALYs), and cost per QALY gained were the outcome measures. MethodsA Markov model tracked health utility and costs over 10 years for a 65-year-old cohort under three care strategies: conservative care, spacer surgery, and decompression surgery. Incremental cost-effectiveness ratios (ICER) reported as cost per QALY gained included direct medical costsfor surgery. Medicare claims data were used to estimate complication rates, reoperation, and related costs within 3 years. Utilities and long-term reoperation rates for decompression were derived frompublished studies. Spacer failure requiring reoperation beyond 3 years and post-spacer health utilities are uncertain and were evaluated through sensitivity analyses. In the base-case, the spacer failure rate was held constant for years 4–10 (cumulative failure: 47%). In a “worst-case” analysis, the 10-year cumulative reoperation rate was increased steeply (to 90%). Threshold analyses were performed to determine the impact of failure and post-spacer health utility on the cost-effectiveness of spacer surgery. ResultsThe spacer strategy had an ICER of $89,500/QALY gained under base-case assumptions, and remained under $100,000 as long as the 10-year cumulative probability of reoperation did not exceed 54%. Under worst-case assumptions, the spacer ICER was $482,000/QALY and fell below $100,000 only if post-spacer utility was 0.01 greater than post-decompression utility or the cost of spacer surgery was $1,600 less than the cost of decompression surgery. ConclusionsSpacers may provide a reasonably cost-effective initial treatment option for patients with lumbar spinal stenosis. Their value is expected to improve if procedure costs are lower in outpatient settings where these procedures are increasingly being performed. Decision analysis is useful for characterizing the long-term cost-effectiveness potential for minimally invasive spinal stenosis treatments and highlights the importance of complication rates and prospective health utility assessment.

227 Surgical Management of Ewing's Sarcoma of the Spine

Abstract INTRODUCTION Treatment of primary Ewing's sarcoma of the spine is complex and requires multiple treatment modalities. Ambiguity remains regarding the role and optimal type of surgery in the treatment of spinal Ewing's sarcoma. The aim of this study was to quantify mortality and local recurrence rates after surgical treatment of spinal Ewing's sarcoma and to determine whether an Enneking appropriate procedure (en bloc resection with wide/marginal margins) and surgical margins are associated with improved prognosis. METHODS The AOSpine Knowledge Forum Tumor developed a comprehensive multicenter database including demographics, diagnosis, treatment, mortality, and recurrence rate data for Ewing's sarcoma the spine. Patients were analyzed based on surgical margins and Enneking appropriateness. Survival and recurrence were analyzed using Kaplan-Meier curves and log-rank tests. RESULTS &gt;Fifty-eight patients diagnosed with primary Ewing's sarcoma of the spine underwent surgery between 1981 and 2012. Enneking appropriateness of surgery was known for 55 patients; 24 (44%) treated Enneking appropriately (EA) and 31 (56%) treated Enneking inappropriately (EI). The 5-year survival was 75% (N = 18) for EA patients and 52% (N = 16) for EI patients. A statistically significant difference in favor of greater survival for EA-treated patients was found (P = 0.034). Neoadjuvant and postoperative chemotherapy was significantly associated with increased survival (P = 0.008). Local recurrence occurred in 22% (N = 5) of patients with an EA procedure versus 38% (N = 11) of patients with an EI procedure. Although, local control was not significantly different between Enneking cohorts (P = 0.140), surgical margins and previous spine tumor operation were associated with local recurrence (P = 0.025 and P = 0.018, respectively). CONCLUSION Primary spinal Ewing's sarcoma requires multiple treatment modalities. Surgery should be undertaken when an en bloc resection with wide/marginal margins can be performed because an Enneking appropriate surgery is associated with improved survival. En bloc resection with wide/marginal margins is associated with local control.

Design and modeling of linearly-constrained compliant spines for human-scale locomotion on rocky surfaces

We present a new spine solution for the locomotion of human-scale robots on steep, rocky surfaces, known as linearly-constrained spines. The spine stiffness is low in the normal direction but high with respect to lateral and bending loads. The solution differs from previous spine arrays used for small robots in having a much higher spine density and less spine scraping over asperities. We present theoretical and empirical results to demonstrate that this solution is capable of shear stresses of over 200kPa, enabling human-scale robots to apply forces parallel to steep rock surfaces for climbing, bracing, etc. The analysis includes the effects of spine geometry, stiffness, backlash and three-dimensional loading angle to predict the overall forces possible in three dimensions of both single and opposed configurations of spine arrays. Demonstrated applications include a gripper for a “smart staff” aimed at helping humanoid robots to negotiate steep terrain and a palm that provides over 700N in shear for the RoboSimian quadruped.

Lumbar microdiscectomy and post-operative activity restrictions: a protocol for a single blinded randomised controlled trial

BackgroundLumbar microdiscectomy is the most commonly performed spinal surgery procedure, with over 300,000 cases performed annually in the United States alone. Traditionally, patients were advised to restrict post-operative activity as this was believed to reduce the risk of disc reherniation and progressive instability. However, this practice would often delay patients return to work. In contemporary practice many surgeons do not restrict patient post-operative activity due to the perception this practice is unnecessary. We describe a randomised controlled trial to assess the impact of activity restrictions on clinical outcome following lumbar discectomy.Methods/DesignThe lumbar microdiscectomy and post-operative activity restriction trial is a multi-centre, randomised, controlled single blinded trial. Two hundred ten patients due to undergo single level lumbar microdiscectomy without a history of previous spine surgery, infection or fracture are randomised to be advised either restricted or unrestricted activity for a period of 30 days following lumbar microdiscectomy. Actual adherence with trial allocation will be monitored bioelectronically via a wearable device. Outcome assessment at follow up will occur at 1, 3, 6 and 12 months. The primary outcome will be a composite endpoint comprising changes in Visual Analogue Scale (Leg and Back), Oswestry Disability Index and the absence of intervertebral disc reherniation or secondary intervention.DiscussionThis randomised controlled trial will directly compare post-operative protocols of activity restrictions and no restrictions following lumbar discectomy with adherence monitored bioelectronically.Trial RegistrationAustralian New Zealand Clinical Trials Registry: ACTRN12616001360404 (retrospectively registered 30/09/2016).

Two-Year Results of the Prospective Spine Treatment Outcomes Study: An Analysis of Complication Rates, Predictors of Their Development, and Effect on Patient Derived Outcomes at 2 Years for Surgical Management of Cervical Spondylotic Myelopathy.

To investigate the baseline patient characteristics, nonoperative modalities, surgical procedures, and complications rates of surgical cervical spondylotic myelopathy (CSM) patients. To evaluate risk factors for developing complications and compare the changes in health-related quality of life (HRQOL) from baseline to 2 years postoperatively. A retrospective review was performed on a prospectively collected database of CSM patients. Baseline patient demographic data, comorbidities, clinical information, nonoperative treatment modalities, surgical procedures, and complication rates were collected. HRQOL outcomes were assessed using the Short Form 36 (SF-36) Physical Score Component (PCS) and Mental Score Component (MCS) and the Neck Disability Index (NDI) at baseline and 2 years postoperatively. Statistical analyses included paired-sample t tests and multivariate logistic regression controlling for age, sex, and body mass index (BMI). A total of 203 surgical CSM patients were identified (43% female). Average age was 57.7 years and average BMI was 29.6 kg/m2. Before surgical intervention, patients underwent various nonoperative treatment modalities, most commonly nonsteroidal anti-inflammatory drugs (34%), analgesics (32%), and physical therapy (26%). The overall rate of complications was 7.4%. Complications included cerebrospinal fluid leak (2.5%), postoperative radiculopathy (1.0%), and excessive bleeding (1.0%). A previous history of cervical spine surgery was the sole significant risk factor for developing a complication (odds ratio, 9.22; P= 0.034). Average HRQOL scores improved significantly from baseline to 2 years postsurgery. The overall complication rate was 7.4% for the cohort. Baseline clinical information, comorbidities, use of nonoperative treatment modalities, and procedure type were not significantly associated with an increased risk of complications. Previous cervical spine surgery increased the risk of complications by 9-fold. The patients showed significantly improved SF-36 PCS, SF-36 MCS, and NDI scores at 2 years after surgery.

Incidental durotomy in decompression for lumbar spinal stenosis: incidence, risk factors and effect on outcomes in the Spine Tango registry.

The three aims of this Spine Tango registry study of patients undergoing decompression for spinal stenosis were to: report the rate of dural tear (DT) stratified by treatment centre; find factors associated with an increased likelihood of incurring a DT; and compare treatment outcomes in relation to DT (none vs. repaired vs. unrepaired DT). Multivariate logistic regression was used to assess the association between DT and patient and treatment characteristics. Patient-rated and surgical outcomes were compared in patients with no DT, repaired DT, and unrepaired DT, while adjusting for case-mix. DT occurred in 328/3254 (10.1%) of included patients. The rate for all 29 contributing hospitals was within 95% confidence intervals of the average. The likelihood of DT increased by 2% per year of age, 1.78 times with previous spine surgery, 1.67 for a minimally/less invasive surgery, 1.58 times with laminectomy, and 1.40, and 2.12 times for BMI 31-35, and >35 in comparison with BMI 26-30, respectively. The majority of DTs (272/328; 82.9%) were repaired. Repairing the DT was associated with a longer duration of surgery (p<0.001). More patients with repaired than with unrepaired DTs were satisfied with treatment, but the difference was not statistically significant. There was no association between DT and patient-reported outcomes. The unadjusted rate of incidental DT during decompression for LSS was homogeneous across the participating centres and was associated with age, BMI, previous surgery at the same spinal level, minimally/less invasive surgery, and laminectomy. Non-repair of DTs had no negative association with treatment outcome; however, the unrepaired DTs may have been those that were smaller in size.

Reliability and Validity Study of the Finnish Adaptation of Scoliosis Research Society Questionnaire Version SRS-30

A prospective clinical study to test and adapt a Finnish version of the Scoliosis Research Society 30 (SRS-30) questionnaire. The aim of this study was to perform cross-cultural adaptation and evaluate the validity of the adapted Finnish version of the SRS-30 questionnaire. The SRS-30 questionnaire has proved to be a valid instrument in evaluating health-related quality of life (HRQoL) in adolescent and adult population with spine deformities in the United States. Multinational availability requires cross-cultural and linguistic adaptation and validation of the instrument. The SRS-30 was translated into Finnish using accepted methods for translation of quality-of-life questionnaires. A total of 274 adult patients with degenerative radiographic sagittal spinal disorder answered the questionnaire with sociodemographic data, RAND 36-item health survey questionnaire (RAND Corp. Health, Santa Monica, CA, US), Oswestry disability index, DEPS depression scale, and Visual Analog Scale (VAS) back and leg pain scales within 2 weeks' interval. The cohort included patients with and without previous spine surgery. Internal consistency and validity were tested with Cronbach α, intraclass correlation (ICC), standard error of measurement, and Spearman correlation coefficient with 95% confidence intervals (CIs). The internal consistency of SRS-30 was good in both surgery and nonsurgery groups, with Cronbach α 0.853 (95% CI, 0.670 to 0.960) and 0.885 (95% CI, 0.854 to 0.911), respectively. The test-retest reproducibility ICC of the SRS-30 total and subscore domains of patients with stable symptoms was 0.905 (95% CI, 0.870-0.930) and 0.904 (95% CI, 0.871-0.929), respectively. The questionnaire had discriminative validity in the pain, self-image, and satisfaction with management domains compared with other questionnaires. The SRS-30 questionnaire proved to be valid and applicable in evaluating HRQoL in Finnish adult spinal deformity patients. It has two domains related to deformity that are not covered by other generally used questionnaires. 3.