Loss of nucleus accumbens low-frequency fluctuations is a signature of chronic pain.

Chronic pain is a highly prevalent disease with poorly understood pathophysiology. In particular, the brain mechanisms mediating the transition from acute to chronic pain remain largely unknown. Here, we identify a subcortical signature of back pain. Specifically, subacute back pain patients who are at risk for developing chronic pain exhibit a smaller nucleus accumbens volume, which persists in the chronic phase, compared to healthy controls. The smaller accumbens volume was also observed in a separate cohort of chronic low-back pain patients and was associated with dynamic changes in functional connectivity. At baseline, subacute back pain patients showed altered local nucleus accumbens connectivity between putative shell and core, irrespective of the risk of transition to chronic pain. At follow-up, connectivity changes were observed between nucleus accumbens and rostral anterior cingulate cortex in the patients with persistent pain. Analysis of the power spectral density of nucleus accumbens resting-state activity in the subacute and chronic back pain patients revealed loss of power in the slow-5 frequency band (0.01 to 0.027 Hz) which developed only in the chronic phase of pain. This loss of power was reproducible across two cohorts of chronic low-back pain patients obtained from different sites and accurately classified chronic low-back pain patients in two additional independent datasets. Our results provide evidence that lower nucleus accumbens volume confers risk for developing chronic pain and altered nucleus accumbens activity is a signature of the state of chronic pain.

Brain Structure and Function of Chronic Low Back Pain Patients on Long-Term Opioid Analgesic Treatment: A Preliminary Study.

Chronic low back pain (CLBP) is often treated with opioid analgesics (OA), a class of medications associated with a significant risk of misuse. However, little is known about how treatment with OA affect the brain in chronic pain patients. Gaining this knowledge is a necessary first step towards understanding OA associated analgesia and elucidating long-term risk of OA misuse. Here we study CLBP patients chronically medicated with opioids without any evidence of misuse and compare them to CLBP patients not on opioids and to healthy controls using structural and functional brain imaging. CLBP patients medicated with OA showed loss of volume in the nucleus accumbens and thalamus, and an overall significant decrease in signal to noise ratio in their sub-cortical areas. Power spectral density analysis (PSD) of frequency content in the accumbens' resting state activity revealed that both medicated and unmedicated patients showed loss of PSD within the slow-5 frequency band (0.01-0.027 Hz) while only CLBP patients on OA showed additional density loss within the slow-4 frequency band (0.027-0.073 Hz). We conclude that chronic treatment with OA is associated with altered brain structure and function within sensory limbic areas.

Two-year clinical outcomes of a multicenter randomized controlled trial comparing two interspinous spacers for treatment of moderate lumbar spinal stenosis.

BACKGROUND: Interspinous spacers are a minimally invasive surgical alternative for patients with lumbar spinal stenosis (LSS) unresponsive to conservative care. The purpose of this prospective, multicenter, randomized, controlled trial was to compare 2-year clinical outcomes in patients with moderate LSS treated with the Superion(®) (Experimental) or the X-Stop(®), a FDA-approved interspinous spacer (Control). METHODS: A total of 250 patients with moderate LSS unresponsive to conservative care were randomly allocated to treatment with the Experimental (n = 123) or Control (n = 127) interspinous spacer and followed through 2 years post-treatment. Complication data were available for all patients and patient-reported outcomes were available for 192 patients (101 Experimental, 91 Control) at 2 years. RESULTS: Zurich Claudication Questionnaire (ZCQ) Symptom Severity and Physical Function scores improved 34% to 36% in both groups through 2 years (all p < 0.001). Patient Satisfaction scores at 2 years were 1.8 ± 0.9 with Experimental and 1.6 ± 0.8 with Control. Axial pain decreased from 59 ± 26 mm at baseline to 21 ± 26 mm at 2 years with Experimental and from 55 ± 26 mm to 21 ± 25 mm with Control (both p < 0.001). Extremity pain decreased from 67 ± 24 mm to 14 ± 22 mm at 2 years with Experimental and from 63 ± 24 mm to 18 ± 23 mm with Control (both p < 0.001). Back function assessed with the Oswestry Disability Index similarly improved with Experimental (37 ± 12% to 18 ± 16%) and Control (39 ± 12% to 20 ± 16%) (both p < 0.001). Freedom from reoperation at the index level was 84% for Experimental and 83% for Control (log-rank: p = 0.38) at 2 years. CONCLUSIONS: Both interspinous spacers effectively alleviated pain and improved back function to a similar degree through 2 years in patients with moderate LSS who were unresponsive to conservative care. TRIAL REGISTRATION: NCT00692276.

Recent advances in the prevention and management of complications associated with routine lumbar spine surgery.

Lumbar spine surgery is often associated with complications in the perioperative and postoperative periods. Evidence-based literature in the prevention and management of adverse events, including surgical site infection, venous thromboembolism, and positioning-related complications, has advanced the understanding of the etiology of these complications and preventive measures. Cost-effective measures to reduce intraoperative bleeding can lead to a lower incidence of infection, disease transmission, and morbidity in the postoperative period. As the healthcare system receives additional scrutiny with value-based assessments, surgeons, hospitals, and administrators will need to make critical decisions to prevent and manage the complications of lumbar spine surgery.

Evolving Trends in the Use of Sacroiliac Fusion From 2015 to 2020.

STUDY DESIGN: Retrospective cohort analysis. OBJECTIVE: To assess the evolution of patients undergoing sacroiliac (SI) fusion with minimally invasive surgery (MIS) relative to open approaches. SUMMARY OF BACKGROUND DATA: The SI joint can be a contributor to lumbopelvic symptoms. The MIS approach to SI fusion has been shown to have fewer complications compared with the open approach. Recent trends and evolved patient populations have not been well-characterized. MATERIALS AND METHODS: Data were abstracted from the large, national, multi-insurance, administrative 2015-2020 M151 PearlDiver database. The incidence, trends, and patient characteristics of MIS, as well as open, SI fusions for adult patients with degenerative indications, were determined. Univariable and multivariable analyses were then performed to compare the MIS relative to open populations. The primary outcome was to assess the trends of MIS and open approaches for SI fusions. RESULTS: In total, 11,217 SI fusions were identified (of which 81.7% were MIS), with a clear increase in numbers over the years from 2015 (n=1318, 62.3% of which were MIS) to 2020 (n=3214 86.6% of which were MIS). Independent predictors of MIS (as opposed to open) SI fusion included: older age (odds ratio [OR] 1.09 per decade increase), higher Elixhauser-Comorbidity Index (OR 1.04 per two-point increase), and geographic region (relative to South, Northeast OR 1.20 and West OR 1.64). As might be expected, 90-day adverse events were lower for MIS than open cases (OR 0.73). CONCLUSION: The presented data quantify the increasing incidence of SI fusions over the years, with the increase being driven by MIS cases. This was largely related to an expanded population (those who are older and with greater comorbidity), fitting the definition of disruptive technology with lesser adverse events than open procedures. Nonetheless, geographic variation highlights the differential adoption of this technology.

Comparison of axial and anterior interbody fusions of the L5-S1 segment: a retrospective cohort analysis.

STUDY DESIGN: Retrospective, multicenter review of 96 patients who underwent L5-S1 interbody fusions through either a standard anterior retroperitoneal approach or using a novel device inserted through the presacral space (AxiaLIF) in conjunction with supplemental posterior fixation between 2002 and 2010. OBJECTIVE: To compare the radiographic fusion rates and adverse events associated with anterior lumbar interbody fusion (ALIF) and AxiaLIF techniques. SUMMARY OF BACKGROUND DATA: Interbody fusions of the lumbosacral spine are frequently performed to provide anterior column support, increase the amount of surface area for bone formation, and facilitate deformity reduction. A number of different surgical approaches have been developed for this purpose including minimally invasive techniques. MATERIALS AND METHODS: Patient information and procedural data were obtained from hospital charts. Multiplanar computed tomography images were evaluated by 2 independent observers to assess fusion success at 24 months using a 4-point grading scale. In addition to reviewing the medical records to identify any complications, all of the sites were queried regarding any device-related adverse events that may have occurred. RESULTS: According to the radiographic analysis, the arthrodesis rates recorded for the ALIF and AxiaLIF cohorts were 79% and 85%, respectively (P>0.05). The numbers and types of adverse events recorded for these procedures appeared to be similar although there was 1 serious intraoperative complication (iliac artery laceration) noted in the ALIF group. CONCLUSIONS: The radiographic success and adverse events associated with AxiaLIF appear to be similar to that observed for ALIF, suggesting that this technique represents a safe and effective method for achieving an interbody fusion across the L5-S1 disk space when utilized in conjunction with posterior fixation.

Lumbar spinal stenosis.

Lumbar spinal stenosis affects many patients and is one of the most common reasons for spinal surgery in the elderly population. New research and surgical innovations have resulted in a better understanding of the disease and its diagnosis and treatment. To select the optimal treatment approach for each patient, it is helpful to review patient presentations, diagnostic workups, surgical and nonsurgical treatment options, evidence-based outcomes, and the pathophysiology of lumbar spinal stenosis.

Longitudinal Comparative Analysis of Complications and Subsequent Interventions Following Stand-Alone Interspinous Spacers, Open Decompression, or Fusion for Lumbar Stenosis.

INTRODUCTION: For individuals with lumbar spinal stenosis (LSS), minimally invasive procedures such as an interspinous spacer device without decompression or fusion (ISD) or open surgery (i.e., open decompression or fusion) may relieve symptoms and improve functions when patients fail to respond to conservative therapies. This research compares longitudinal postoperative outcomes and rates of subsequent interventions between LSS patients treated with ISD and those with open decompression or fusion as their first surgical intervention. METHODS: This retrospective, comparative claims analysis identified patients age ≥ 50 years with LSS diagnosis and with a qualifying procedure during 2017-2021 in the Medicare database which includes healthcare encounters in inpatient and outpatient settings. Patients were followed from the qualifying procedure until end of data availability. The outcomes assessed during the follow-up included subsequent surgical interventions, including subsequent fusion and lumbar spine surgeries, long-term complications, and short-term life-threatening events. Additionally, the costs to Medicare during a 3-year follow-up were calculated. Cox proportional hazards, logistic regression, and generalized linear models were used to compare outcomes and costs, adjusted for baseline characteristics. RESULTS: A total of 400,685 patients who received a qualifying procedure were identified (mean age 71.5 years, 50.7% male). Compared to ISD patients, patients receiving open surgery (i.e., decompression and/or fusion) were more likely to have a subsequent fusion [hazard ratio (HR), 95% confidence intervals (CI): 1.49 (1.17, 1.89)-2.54 (2.00, 3.23)] or other lumbar spine surgery [HR (CI): 3.05 (2.18, 4.27)-5.72 (4.08, 8.02)]. Short-term life-threatening events [odds ratio (CI): 2.42 (2.03, 2.88)-6.36 (5.33, 7.57)] and long-term complications [HR (CI): 1:31 (1.13, 1.52)-2.38 (2.05, 2.75)] were more likely among the open surgery cohorts. Adjusted mean index costs were lowest for decompression alone (US$7001) and highest for fusion alone ($33,868). ISD patients had significantly lower 1-year complication-related costs than all surgery cohorts and lower 3-year all-cause costs than fusion cohorts. CONCLUSIONS: ISD resulted in lower risks of short- and long-term complications and lower long-term costs than open decompression and fusion surgeries as a first surgical intervention for LSS.

Minimally Invasive SI Joint Fusion Procedures for Chronic SI Joint Pain: Systematic Review and Meta-Analysis of Safety and Efficacy.

BACKGROUND: Sacroiliac (SI) joint fusion is increasingly used to treat chronic SI joint pain. Multiple surgical approaches are now available. METHODS: Data abstraction and random effects meta-analysis of safety and efficacy outcomes from published patient cohorts. Patient-reported outcomes (PROs) and safety measures were stratified by surgical technique: transiliac, including lateral transiliac (LTI) and posterolateral transiliac (PLTI), and posterior interpositional (PI) procedures. RESULTS: Fifty-seven cohorts of 2851 patients were identified, including 43 cohorts (2126 patients) for LTI, 6 cohorts (228 patients) for PLTI, and 8 cohorts (497 patients) for PI procedures. Randomized trials were only available for LTI. PROs were available for pain (numeric rating scale) in 57 cohorts (2851 patients) and disability (Oswestry Disability Index [ODI]) in 37 cohorts (1978 patients).All studies with PROs showed improvement from baseline after surgery. Meta-analytic improvements in pain scores were highest for LTI (4.8 points [0-10 scale]), slightly lower for PLTI (4.2 points), and lowest for PI procedures (3.8 points, P = 0.1533). Mean improvements in ODI scores were highest for LTI (25.9 points), lowest for PLTI procedures (6.8 points), and intermediate for PI (16.3 points, P = 0.0095).For safety outcomes, acute symptomatic implant malposition was 0.43% for LTI, 0% for PLTI, and 0.2% for PI procedures. Wound infection was reported in 0.15% of LTI, 0% of PLTI, and 0% of PI procedures. Bleeding requiring surgical intervention was reported in 0.04% of LTI procedures and not reported for PLTI or PI. Breakage and migration were not reported for any device. Radiographic imaging evaluation reporting implant placement accuracy and fusion was only available for LTI. DISCUSSION: Literature support for SI joint fusion is growing. The LTI procedure contains the largest body of available evidence and shows the largest improvements in pain and ODI. Only LTI procedures have independent radiographic evidence of fusion and implant placement. The adverse event rate for all procedures was low.

Better Functional Recovery After Single-Level Compared With Two-Level Posterolateral Lumbar Fusion.

Background Multiple studies describe the outcomes of patients undergoing single-level and multilevel posterolateral lumbar fusion (PLF). However, a comparison of outcomes between single-level and two-level PLF is lacking. The aim of this prospective cohort study was to compare outcomes between single-level and two-level instrumented PLF. Methods A total of 42 patients were enrolled at nine US centers between October 2015 and June 2017. Data included radiologic outcomes, visual analog scale (VAS) Back and Leg Pain, disability per the Oswestry Disability Index (ODI), and health-related quality of life (QoL) per 36-Item Short Form Survey version 2.0 (SF-36v2) at six weeks and three, six, 12, and 24 months. Results Twelve-month and 24-month follow-ups were completed by 38 (90.5%) and 32 (76.2%) subjects, respectively. The average age was 67 years, and 54.8% were female. Twenty-six received single-level PLF, and 16 received two-level PLF. In the single-level group, there was one reoperation, two postoperative infections, and one dural tear. In the two-level group, there was one postoperative infection. The surgeon computed tomography (CT)-based evaluation of fusion rate was 67.6% (25/37) at 12-month follow-up and 94.1% (32/34) at 24-month follow-up. The third-party evaluation of fusion rate was 52.8% (19/36) at six months, 81.1% (30/37) at 12 months, and 86.5% (32/37) at 24 months. There was a tendency toward a higher fusion rate in single-level compared with two-level PLF. The ODI, SF-36v2 Mental Component Score (MCS), and VAS Back Pain and Leg Pain outcomes improved by the first follow-up visit in both the single-level and two-level groups. Improvement in the ODI was 5.86 (95% confidence interval (CI): 0.03-11.69) points greater in the single-level group compared with the two-level group. Conclusions Compared with the two-level PLF subjects, single-level PLF subjects had better functional outcomes and reported higher satisfaction with the outcome of surgery but showed similar fusion, pain, and generic health-related quality of life outcomes. Both single-level and two-level PLF subjects demonstrated high fusion rates in association with improvements in pain, functional, and quality of life outcomes, as well as high satisfaction levels.

A comparison of in-hospital outcomes after elective anterior cervical discectomy and fusion in cases with and without Parkinson's Disease.

Background: Following orthopedic surgery, patients with Parkinson's disease (PD) have been shown to have high rates of surgical complications, and some studies suggest that PD may be associated with greater risk for postoperative medical complications. As complication rates are critical to consider for elective surgery planning, the current study aimed to describe the association of PD with medical complications following anterior cervical discectomy and fusion (ACDF), the most commonly performed procedure to treat cervical degenerative pathology. Methods: The 2008-2018 National Inpatient Sample database was queried for cases involving elective ACDF. Demographics and comorbidities were extracted using ICD codes. Cases were propensity matched based on demographic and comorbidity burden, and logistic regression was used to compare in-hospital complications between patients with and without PD. Results: After weighting, a total of 1,273,437 elective ACDF cases were identified, of which 3948 (0.31%) involved cases with PD. After 1:1 propensity score matching by demographic and comorbidity variables, there were no differences between the PD and non-PD cohorts. Logistic regression models constructed for the matched and unmatched populations showed that PD cases have greater odds of in-hospital minor adverse events with no differences in odds of serious adverse events or mortality. Conclusions: After matching for demographics and comorbidity burden, PD cases undergoing elective ACDF had slightly longer length of stay and greater risk for minor adverse events but had similar rates of serious adverse events and mortality. These findings are important for surgeons and patients to consider when making decisions about surgical intervention.

The development and evaluation of the subaxial injury classification scoring system for cervical spine trauma.

BACKGROUND: Fractures and dislocations of the subaxial cervical spine may give rise to devastating consequences. Previous algorithms for describing cervical trauma largely depend on retrospective reconstructions of injury mechanism and utilize nonspecific terminology which thus diminish their clinical relevance add to the difficulty of educating doctors and performing prospective research. QUESTIONS/PURPOSES: We characterized the potential benefits of the Subaxial Injury Classification (SLIC) scale which considers three major variables that influence spinal stability: morphology, integrity of the discoligamentous complex, and neurologic status. Each category was assigned a certain number of points based on the severity of the injury which are added together to generate a total score; this value provides prognostic information and may also be useful for directing subsequent management (ie, nonoperative treatment versus operative intervention). METHODS: We examined the individual components that comprise the SLIC paradigm and reviewed the manner in which cervical injuries are scored and stratified. We also critically assessed the preliminary data comparing the SLIC scheme to preexisting classification systems. RESULTS: The results of a preliminary analysis demonstrate that the intraclass coefficients (ICC) for the three primary components range between 0.49 and 0.90, suggesting that the overall reliability of the SLIC system appears to be at least as good as that of other conventional schemes for classifying subaxial cervical spine trauma (ICC between 0.41 and 0.53). CONCLUSIONS: This scheme will hopefully facilitate the development of evidence-based guidelines that may influence other aspects of the therapeutic decision-making process (eg, which operative approach is most appropriate for a particular injury). We anticipate its accuracy and reproducibility will increase over time as surgeons become more familiar with the protocol.

Cement Augmentation of Vertebral Compression Fractures May Be Safely Considered in the Very Elderly.

OBJECTIVE: The objective of the current study was to perform a retrospective review of a national database to assess the safety of cement augmentation for vertebral compression fractures in geriatric populations in varying age categories. METHODS: The 2005-2016 National Surgical Quality Improvement Program databases were queried to identify patients undergoing kyphoplasty or vertebroplasty in the following age categories: 60-69, 70-79, 80-89, and 90+ years old. Demographic variables, comorbidity status, procedure type, provider specialty, inpatient/outpatient status, number of procedure levels, and periprocedure complications were compared between age categories using chi-square analysis. Multivariate logistic regressions controlling for patient and procedural variables were then performed to assess the relative periprocedure risks of adverse outcomes of patients in the different age categories relative to those who were 60-69 years old. RESULTS: For the 60-69, 70-79, 80-89, and 90+ years old cohorts, 486, 822, 937, and 215 patients were identified, respectively. After controlling for patient and procedural variables, 30-day any adverse events, serious adverse events, reoperation, readmission, and mortality were not different for the respective age categories. Cases in the 80- to 89-year-old cohort were at increased risk of minor adverse events compared to cases in the 60- to 69-year-old cohort. CONCLUSION: As the population ages, cement augmentation is being considered as a treatment for vertebral compression fractures in increasingly older patients. These results suggest that even the very elderly may be appropriately considered for these procedures (level of evidence: 3).

Normal functional range of motion of the cervical spine during 15 activities of daily living.

STUDY DESIGN: Prospective clinical study. OBJECTIVE: The purpose of this investigation was to quantify normal cervical range of motion (ROM) and compare these results to those used to perform 15 simulated activities of daily living (ADLs) in asymptomatic subjects. SUMMARY OF BACKGROUND DATA: Previous studies looking at cervical ROM during ADLs have been limited and used measuring devices that do not record continuous motion. The purpose of this investigation was to quantify normal cervical ROM and compare these results with those used to perform 15 simulated ADLs in asymptomatic subjects. METHODS: A noninvasive electrogoniometer and torsiometer were used to measure the ROM of the cervical spine. The accuracy and reliability of the devices were confirmed by comparing the ROM values acquired from dynamic flexion/extension and lateral bending radiographs to those provided by the device, which was activated while the radiographs were obtained. Intraobserver reliability was established by calculating the intraclass correlation coefficient for repeated measurements on the same subjects by 1 investigator on consecutive days. These tools were employed in a clinical laboratory setting to evaluate the full active ROM of the cervical spines (ie, flexion/extension, lateral bending, and axial rotation) of 60 asymptomatic subjects (30 females and 30 males; age, 20 to 75 y) as well as to assess the functional ROM required to complete 15 simulated ADLs. RESULTS: When compared with radiographic measurements, the electrogoniometer was found to be accurate within 2.3+/-2.2 degrees (mean+/-SD) and the intraobserver reliabilities for measuring the full active and functional ROM were both excellent (intraclass correlation coefficient of 0.96 and 0.92, respectively). The absolute ROM and percentage of full active cervical spinal ROM used during the 15 ADLs was 13 to 32 degrees and 15% to 32% (median, 20 degrees/19%) for flexion/extension, 9 to 21 degrees and 11% to 27% (14 degrees/18%) for lateral bending, and 13 to 57 degrees and 12% to 92% (18 degrees/19%) for rotation. Backing up a car required the most ROM of all the ADLs, involving 32% of sagittal, 26% of lateral, and 92% of rotational motion. In general, personal hygiene ADLs such as washing hands and hair, shaving, and applying make-up entailed a significantly greater ROM relative to locomotive ADLs including walking and traveling up and down a set of stairs (P<0.0001); in addition, compared with climbing up these steps, significantly more sagittal and rotational motion was used when descending stairs (P=0.003 and P=0.016, respectively). When picking up an object from the ground, a squatting technique required a lower percentage of lateral and rotational ROM than bending at the waist (P=0.002 and P<0.0001). CONCLUSIONS: By quantifying the amounts of cervical motion required to execute a series of simulated ADLs, this study indicates that most individuals use a relatively small percentage of their full active ROM when performing such activities. These findings provide baseline data which may allow clinicians to accurately assess preoperative impairment and postsurgical outcomes.

Normal functional range of motion of the lumbar spine during 15 activities of daily living.

STUDY DESIGN: Prospective clinical study. OBJECTIVE: The purpose of this investigation was to quantify normal lumbar range of motion (ROM) and compare these results with those used to perform 15 simulated activities of daily living (ADLs) in asymptomatic subjects. SUMMARY OF BACKGROUND DATA: Previous studies reporting the ROM of the lumbar spine during ADLs have been limited, only focusing on 4 ADLs. The purpose of this investigation was to quantify the extent of normal lumbar ROM and determine how much motion is necessary to perform 15 simulated ADLs. METHODS: A noninvasive electrogoniometer and torsiometer were used to measure the ROM of the lumbar spine. The accuracy and reliability of the devices were confirmed by comparing the ROM values acquired from dynamic flexion/extension and lateral bending radiographs with those provided by the device that was activated while the radiographs were obtained. Intraobserver reliability was established by calculating the intraclass correlation coefficient for repeated measurements on the same subjects by 1 investigator on consecutive days. These tools were employed in a clinical laboratory setting to evaluate the full active ROM of the lumbar spines (ie, flexion/extension, lateral bending, and axial rotation) of 60 asymptomatic subjects (30 women and 30 men; age 20 to 75 y) and to assess the functional ROM required to complete 15 simulated ADLs. RESULTS: When compared with radiographic measurements, the electrogoniometer was found to be accurate within 2.3+/-2.6 degrees (mean+/-SD). The intraobserver reliabilities for assessing full and functional ROM were both excellent (intraclass correlation coefficient of 0.96 and 0.88, respectively). The absolute ROM and percentage of full active lumbar spinal ROM used during the 15 ADLs was 3 to 49 degrees and 4% to 59% (median: 9 degrees/11%) for flexion/extension, 2 to 11 degrees and 6% to 31% (6 degrees/17%) for lateral bending, and 2 to 7 degrees and 6% to 20% (5 degrees/13%) for rotation. Picking up an object from the ground, either using a bending or squatting technique, required the most ROM of all the ADLs. Squatting required a significantly less amount of sagittal motion compared with bending at the waist (42 vs. 48 degrees, P=0.003). No difference was seen in both lateral and rotation motion between these 2 techniques (11 vs. 11 degrees and 6 vs. 6 degrees, respectively). Both ascending and descending stairs required equivalent amounts of total motion in all 3 motion planes. As a whole, personal hygiene ADLs (hand washing, washing hair, shaving, and make-up application) required a similar amount of motion compared with the 3 locomotive ADLs (walking, up and down stairs). CONCLUSIONS: By quantifying the amounts of lumbar motion required to execute a series of simulated ADLs, this study indicates that most individuals use a relatively small percentage of their full active ROM when performing such activities. These findings provide baseline data that may allow clinicians to accurately assess preoperative impairment and postsurgical outcomes.

Evidence-Based Recommendations for Spine Surgery.

: This next issue of Evidence-Based Recommendations for Spine Surgery examines six articles that seek to address pressing and relevant issues in contemporary spine surgery. These articles explore the safety and efficacy of tranexamic acid during lumbar surgery, the utility of post-operative MRI after spinal decompression surgery, the role of teriparatide for fusion support in osteoporotic patients, sagittal spinopelvic alignment in adults, the comparative effectiveness of lumbar disk arthroplasty and prognostic factors for satisfaction after lumbar decompression surgery. These important publications are examined rigorously - both clinically and methodologically - and recommendations regarding impact on clinical practice are provided.Level of Evidence: N/A.

Which regions of the operating gown should be considered most sterile?

Various guidelines have been proposed regarding which portions of a surgical gown may be considered sterile. Unfortunately, the validity of these recommendations has not been definitively established. We therefore evaluated gown sterility after major spinal surgery to assess the legitimacy of these guidelines. We used sterile culture swabs to obtain samples of gown fronts at 6-inch increments and at the elbow creases of 50 gowns at the end of 29 spinal operations. Another 50 gowns were swabbed immediately after they were applied to serve as negative controls. Bacterial growth was assessed using semiquantitative plating techniques on a nonselective, broad-spectrum media. Contamination was observed at all locations of the gown with rates ranging from 6% to 48%. Compared with the negative controls, the contamination rates were greater at levels 24 inches or less and 48 inches or more relative to the ground and at the elbow creases. The section between the chest and operative field had the lowest contamination rates. Based on these results, we consider the region between the chest and operative field to be the most sterile and any contact with the gown outside this area, including the elbow creases, should be avoided to reduce the risk of infection.