Long-term efficacy of microendoscopic laminotomy for lumbar spinal stenosis in advanced degenerative spondylolisthesis with or without dynamic spinal instability: a propensity score-matching analysis.

OBJECTIVE: In this study, the authors aimed to determine the mid- to long-term outcomes of microendoscopic laminotomy (MEL) for lumbar spinal stenosis (LSS) with degenerative spondylolisthesis (DS) and identify preoperative predictors of poor mid- to long-term outcomes. METHODS: The authors retrospectively reviewed the medical records of 274 patients who underwent spinal MEL for symptomatic LSS. The minimum postoperative follow-up duration was 5 years. Patients were classified into two groups according to DS: those with DS (the DS+ group) and those without DS (the DS- group). The patients were subjected to propensity score matching based on sex, age, BMI, surgical segments, and preoperative leg pain visual analog scale scores. Clinical outcomes were evaluated 1 year and > 5 years after surgery. RESULTS: Surgical outcomes of MEL for LSS were not significantly different between the DS+ and DS- groups at the final follow-up (mean 7.8 years) in terms of Oswestry Disability Index (p = 0.498), satisfaction (p = 0.913), and reoperation rate (p = 0.154). In the multivariate analysis, female sex (standard ß -0.260), patients with slip angle > 5° in the forward bending position (standard ß -0.313), and those with dynamic progression of Meyerding grade (standard ß -0.325) were at a high risk of poor long-term outcomes. CONCLUSIONS: MEL may have good long-term results in patients with DS without dynamic instability. Women with dynamic instability may require additional fusion surgery in approximately 25% of cases for a period of ≥ 5 years.

Responsiveness of the Zurich Claudication Questionnaire in Patients with Lumbar Spinal Stenosis Undergoing Nonsurgical Treatment: A Secondary Analysis of a Randomized Controlled Trial.

STUDY DESIGN: Secondary analysis of a randomized controlled trial. OBJECTIVE: We investigated the ability to distinguish patients with lumbar spinal stenosis (LSS) who improved from those who did not after receiving nonsurgical treatment. We used the disorder-specific Zurich Claudication Questionnaire (ZCQ) satisfaction subscale as an external anchor and estimated the minimal clinically important differences (MCIDs) for the ZCQ symptom severity and physical function subscales. SUMMARY OF BACKGROUND DATA: The ZCQ satisfaction subscale effectively distinguishes surgical patients who improved from those who did not for LSS. However, its responsiveness in nonsurgical treatment has not been evaluated yet. METHODS: Eighty-four patients with LSS who received supervised physical therapy or a home exercise program were included. Patients were classified as responders or nonresponders according to the cutoff of 2.5 for the ZCQ satisfaction subscales at 6 weeks and 1 year. The external responsiveness of the ZCQ satisfaction subscale was assessed using correlational and receiver-operating characteristic (ROC) curve analyses. MCIDs for the ZCQ symptom severity and physical function subscales were estimated using anchor and distribution approaches. RESULTS: Pearson's correlation coefficients between the changes in outcomes and the ZCQ satisfaction subscale at 6 weeks and 1 year were 0.37-0.58 (symptom severity) and 0.40-0.45 (physical function subscales) (>0.30 is considered a good anchor). The area under the ROC curve values were 0.66-0.72 and 0.63-0.71 for the symptom severity and physical function subscales, respectively (>0.7 is considered acceptable). The MCIDs at 6 weeks and 1 year estimated from anchor-based approaches were -0.64 to -0.13 (symptom severity) and -0.39 to 0.10 (physical function), and those from the distribution-based approaches were -0.31 to -0.30 and -0.29 to -0.27, respectively. CONCLUSION: The findings of this study suggest that the ZCQ satisfaction subscale has less ability to distinguish patients with LSS who improved in the ZCQ symptom severity and physical function subscales from those who did not after nonsurgical treatment, compared to those after surgical treatment.

Outcomes and Vertebral Osteophytes and Bulging Intervertebral Discs Occupancy as a Decision-Making Tool for Surgical Success in Patients Undergoing Microendoscopic Foraminotomy for Lumbar Foraminal Stenosis.

OBJECTIVE: The objective of this study was to determine the long-term outcomes of microendoscopic foraminotomy in treating lumbar foraminal stenosis and identify the optimal extent of decompression that yields improved results and fewer complications. METHODS: A retrospective cohort study reviewed the medical records of 95 consecutive patients who underwent microendoscopic foraminotomy for lumbar foraminal stenosis. Clinical outcomes were assessed using the Japanese Orthopaedic Association scoring system and visual analog scale for low back and leg pain. Surgical success was determined by meeting significant improvement thresholds for back and leg pain at 2 years postoperatively. Multiple regression analysis identified factors associated with improved pain scores. Receiver operating characteristic curve analysis determined the cut-off values for successful surgeries. RESULTS: Significant improvements were observed in Japanese Orthopaedic Association and visual analog scale scores for back and leg pain 2 years postoperatively compared with preoperative scores (P < 0.0001) and sustained over a ≥5-year follow-up period. Reoperation rates were low and did not significantly increase over time. Multiple regression analysis identified occupancy of the vertebral osteophytes and bulging intervertebral discs (O/D complex) as surgical success predictors. A 45.0% O/D complex occupancy cutoff value was determined, displaying high sensitivity and specificity for predicting surgical success. CONCLUSIONS: This study provides evidence supporting the long-term efficacy of microendoscopic foraminotomy for lumbar foraminal stenosis and predicting surgical success. The 45.0% O/D complex occupancy cut-off value can guide patient selection and outcome prediction. These insights contribute to informed surgical decision-making and underscore the importance of evaluating the O/D complex in preoperative planning and predicting outcomes.

Minimal clinically important differences in walking capacity and physical activity after nonsurgical treatment in patients with lumbar spinal stenosis: a secondary analysis of a randomized controlled trial.

BACKGROUND CONTEXT: Little information is available about the minimal clinically important differences (MCIDs) for objective physical measurements in people with lumbar spinal stenosis (LSS). PURPOSE: To use disorder-specific anchor and, multiple anchor-, and distribution-based approaches to determine the MCIDs for walking capacity and physical activity in patients with LSS receiving nonsurgical treatment. STUDY DESIGN/SETTING: Secondary analysis of a randomized controlled trial. PATIENT SAMPLE: Sixty-nine patients with neurogenic claudication caused by LSS receiving outpatient physical therapy. OUTCOME MEASURES: Zurich claudication questionnaire (ZCQ), self-paced walking test (SPWT), and number of daily steps measured by pedometry. METHODS: All patients completed the ZCQ, SPWT, and pedometry at the baseline and after 6 weeks. For the anchor-based approach, ZCQ symptom severity, physical function, and satisfaction subscales were used as the external anchors. Using the receiver-operating characteristic (ROC) curve, the MCIDs were determined based on the optimal cutoff points for changes in the SPWT or daily steps. For the distribution-based approach, the MCIDs were estimated from the standard deviations (SDs) of the baseline scores of the SPWT and daily steps. RESULTS: In the anchor-based approach, only the ZCQ satisfaction subscale for the SPWT (0.73), and ZCQ symptom severity subscale for daily steps (0.71) exceeded the area under the ROC curve value of 0.7, which is considered acceptable. When using these subscales as anchors, the ROC curves and optimal cutoff points indicated MCIDs of 151 m for the SPWT and 1,149 steps for daily steps. The distribution-based approach estimated the MCIDs as 280 m for the SPWT and 1,274 steps for daily steps, and had a moderate effect size (0.5 SD). CONCLUSIONS: The anchor-based approach had limited external responsiveness when the ZCQ was used as the anchor. However, this information may be helpful for interpreting walking capacity and physical activity in patients with LSS receiving nonsurgical treatment and for estimating power and sample size when planning new trials.

Assessing the transmission risk of red sea bream iridovirus (RSIV) in environmental water: insights from fish farms and experimental settings.

Aquatic animal viruses are considered to be transmitted via environmental water between fish farms. This study aimed to understand the actual transmission risk of red sea bream iridovirus (RSIV) through environmental water among fish farms. An environmental DNA (eDNA) method using iron-based flocculation coupled with large-pore filtration was used to monitor RSIV DNA copies in seawater from fish farms and from an experimental infection model. RSIV dispersion in seawater from a net pen where the disease outbreak occurred was visualized by the inverse distance weighting method using multiple-sampling data sets from a fish farm. The analysis demonstrated that the center of the net pen had a high viral load, and RSIV seemed to be quickly diluted by the tidal current. To evaluate the transmission risk of RSIV in environmental water, the red sea bream Pagrus major (approximately 10 g) was exposed to RSIV-contained seawater (103, 104, 105, 106, and 107 copies/L) for 3 days, which mimicked field exposure. A probit analysis of the challenge test indicated that the inferred infection rates of seawater containing 105.9 copies/L and 103.1 copies/L of RSIV were 50% and 0.0001%, respectively. In the surveillance for 3 years at 10 fixed points (n = 306), there were only seven samples in which the viral load exceeded 104 copies/L in seawater. These results suggest that the transmission of RSIV among fish farms via seawater is highly associated with the distance between the net pens, and the environmental water is not always an infection source for the transmission of RSIV between fish farms. IMPORTANCE Our surveillance of viral loads for red sea bream iridovirus (RSIV) by monitoring environmental DNA in fish farms suggested that the viral loads in the seawater were low, except for the net pens where RSIV outbreaks occurred. Furthermore, our experimental infection model indicated that the infection risk of RSIV-contained seawater with less than 103 copies/L was extremely low. The limited risk of environmental water for transmission of RSIV gives an insight that RSIV could be partly transmitted between fish farms due to the movement of equipment and/or humans from the fish farm where the disease outbreaks. Since our data suggest that seawater can function as a potential wall to reduce the transmission of RSIV, biosecurity management, such as disinfection of equipment associated with fish farms could be effective, even in the semi-open system aquaculture that the environmental water can be freely transferred, to reduce the risk of RSIV outbreaks.

Lumbar paraspinal muscle morphology is associated with spinal degeneration in patients with lumbar spinal stenosis.

BACKGROUND CONTEXT: Lumbar spinal stenosis (LSS) has been reported to induce changes in paraspinal muscle morphology, but objective physical function and degenerative spine conditions are rarely assessed. PURPOSE: To identify factors associated with paraspinal muscle morphology using objective physical and degenerative spine assessments in patients with LSS. STUDY DESIGN/SETTING: Cross-sectional design. PATIENT SAMPLE: Seventy patients with neurogenic claudication caused by LSS, receiving outpatient physical therapy. OUTCOME MEASURES: Cross-sectional area (CSA) and functional CSA (FCSA) of the multifidus, erector spinae, and psoas muscles, the severity of stenosis, disc degeneration, and endplate abnormalities were evaluated by magnetic resonance imaging, as well as sagittal spinopelvic alignment by X-ray. Objective physical assessments included pedometry and claudication distance. Patient-reported outcomes included the numerical rating scale of low back pain, leg pain, and leg numbness, and the Zurich Claudication Questionnaire. METHODS: To assess the impact of LSS on paraspinal muscles, FCSA and FCSA/CSA were compared between the dominant and nondominant sides based on the patients' neurogenic symptoms, and multivariable regression analyses adjusted for age, sex, height, and weight were performed; p<.05 was considered significant. RESULTS: Seventy patients were analyzed. At one level below the maximum stenotic level, erector spinae FCSA on the dominant side was significantly lower than that on the nondominant side. In the multivariable regression analyses, at one level below the symptomatic level, disc degeneration, endplate abnormalities, and lumbar spinopelvic alignment, such as decreased lumbar lordosis and increased pelvic tilt, were negatively associated with multifidus FCSA and FCSA/CSA ratio. A significant association was observed between dural sac CSA and erector spinae FCSA. Throughout L1/2 to L5/S, disc degeneration, endplate abnormalities, and lumbar spinopelvic alignment were negatively associated with multifidus and erector spinae FCSA or FCSA/CSA. CONCLUSIONS: Lumbar paraspinal muscle asymmetry caused by LSS was observed only in erector spinae. Disc degeneration, endplate abnormalities, and lumbar spinopelvic alignment, rather than spinal stenosis and LSS symptoms, were more associated with paraspinal muscle atrophy or fat infiltration.

Pelvic compensation accompanying spinal malalignment and back pain-related factors in a general population: the Wakayama spine study.

Some older adults with spinal deformity maintain standing posture via pelvic compensation when their center of gravity moves forward. Therefore, evaluations of global alignment should include both pelvic tilt (PT) and seventh cervical vertebra-sagittal vertical axis (C7-SVA). Here, we evaluate standing postures of older adults using C7-SVA with PT and investigate factors related to postural abnormality. This cross-sectional study used an established population-based cohort in Japan wherein 1121 participants underwent sagittal whole-spine radiography in a standing position and bioelectrical impedance analysis for muscle mass measurements. Presence of low back pain (LBP), visual analog scale (VAS) of LBP, and LBP-related disability (Oswestry Disability Index [ODI]) were evaluated. Based on the PT and C7-SVA, the participants were divided into four groups: normal, compensated, non-compensated, and decompensated. We defined the latter three categories as "malalignment" and examined group characteristics and factors. There were significant differences in ODI%, VAS and prevalence of LBP, and sarcopenia among the four groups, although these were non-significant between non-compensated and decompensated groups on stratified analysis. Moreover, the decompensated group was significantly associated with sarcopenia. Individuals with pelvic compensation are at increased risk for LBP and related disorders even with the C7-SVA maintained within normal range.

Branched-chain amino acids plus vitamin D supplementation promote increased muscle strength following lumbar surgery for lumbar spinal stenosis: a randomized trial.

BACKGROUND CONTEXT: Adequate nutrition is essential to address the surgical stress response and mitigate loss of muscle mass, strength, and functionality in older adults with lumbar spinal stenosis (LSS). However, it is unknown whether amino acids and/or vitamin D are beneficial in older adults following lumbar surgery for LSS. PURPOSE: To evaluate whether branched-chain amino acids (BCAA) plus vitamin D supplementation could attenuate the loss of muscle mass and strength, accelerate the return of functional mobility, and improve clinical outcomes following lumbar surgery for LSS. STUDY DESIGN/SETTING: A single-center, single-blind randomized controlled trial. PATIENT SAMPLE: Eighty patients who received lumbar surgery for LSS. OUTCOME MEASURES: The primary outcome was the Zurich claudication questionnaire (ZCQ), and secondary outcomes included knee muscle strength, muscle mass measured by bioelectrical impedance analysis, gait speed and a timed up-and-go test (TUG) at 12 weeks postoperatively. Follow-up assessment was performed for the ZCQ at 52 weeks postoperatively. METHODS: Patients ingested the supplementation (BCAA group: BCAA plus vitamin D, Nonamino acid group: nonamino acid) twice daily for 3 weeks from the day after surgery, and received two hours of postoperative inpatient rehabilitation 5 times a week. RESULTS: No significant differences were observed in the mean changes on the ZCQ between the two groups at 12 weeks and 52 weeks. At 2 weeks postoperatively, the nonamino acid group showed significant deterioration compared with the BCAA group for strengths of knee extensor and knee flexor (p < .01). At 12 weeks, the BCAA group showed significant improvements in knee extensor strength and knee flexor strength compared with the nonamino acid group (p <.01). There were no significant differences in mean changes of muscle mass, maximum gait speed, and TUG at 12 weeks between two groups. CONCLUSIONS: BCAA plus vitamin D supplementation did not improve LSS-related clinical outcomes after lumbar surgery for LSS, even though muscle strength increased. Future studies should focus on long-term outcomes for muscle mass and physical function, including development of sarcopenia and frailty.

Residual Neuropathic Pain in Postoperative Patients With Cervical Ossification of Posterior Longitudinal Ligament.

STUDY DESIGN: A prospective multi-institutional observational study. OBJECTIVE: To investigate and identify risk factors for residual neuropathic pain after surgery in patients with cervical ossification of posterior longitudinal ligament (c-OPLL). SUMMARY OF BACKGROUND DATA: Patients with c-OPLL often require surgery for numbness and paralysis of the extremities; however, postoperative neuropathic pain can considerably deteriorate their quality of life. METHODS: Out of 479 patients identified from multicenter c-OPLL registries between 2014 and 2017, 292 patients who could be followed up for 2 years postoperatively were reviewed, after excluding patients with nervous system comorbidities. Demographic details; medical history; radiographic factors including the K-line, spinal canal occupancy rate of OPLL, cervical kyphosis angle, and presence of spinal cord myelomalacia; preoperative Japanese Orthopaedic Association (JOA) score; surgical procedure (fusion or decompression surgery); postoperative neurological deterioration; and the visual analogue scale for pain and numbness in the upper extremities (U/E) or trunk/lower extremities (L/E) at baseline and at 2 years postoperatively were assessed. Patients were grouped into residual and non-residual groups based on a postoperative visual analogue scale ≥40 mm. Risk factors for residual neuropathic pain were evaluated by multiple logistic regression analysis. RESULTS: The prevalence of U/E and L/E residual pain in postoperative c-OPLL patients was 51.7% and 40.4%, respectively. The U/E residual group had a poor preoperative JOA score and longer illness duration, and fusion surgery was more common in the residual group than in non-residual group. The L/E residual group was older with a poorer preoperative JOA score. On multivariate analysis, risk factors for U/E residual pain were long illness duration and poor preoperative JOA score, whereas those for L/E residual pain were age and poor preoperative JOA score. CONCLUSIONS: The risk factors for residual spinal neuropathic pain after c-OPLL surgery were age, long duration of illness, and poor preoperative JOA score. LEVEL OF EVIDENCE: IV.

Long-Term Outcomes after Selective Microendoscopic Laminotomy for Multilevel Lumbar Spinal Stenosis with and without Remaining Radiographic Stenosis: A 10-Year Follow-Up Study.

Introduction: Long-term clinical outcomes of microendoscopic laminotomy (MEL) for patients with multilevel radiographic lumbar spinal canal stenosis (LSS) have not been widely explored. The clinical significance and natural progression of additional untreated levels (e.g., remaining radiographic (RR)-LSS not addressed by selective MEL) remain unknown. This retrospective study aimed to investigate the long-term clinical outcomes of selective MEL in LSS patients and compare outcomes between patients with and without remaining RR-LSS to determine the efficacy of this procedure. Methods: Forty-nine patients at a single center underwent posterior spinal microendoscopic decompression surgery for neurogenic claudication or radicular leg pain in moderate-to-severe spinal stenosis. The patients were categorized into the RR-LSS-positive and RR-LSS-negative cohorts based on unaddressed levels of stenosis. Pre-operative and 10-year follow-up evaluations, including the Japanese Orthopedic Association (JOA) score, visual analog scale (VAS) score for low back pain and leg pain, Oswestry Disability Index (ODI), and satisfaction, were compared between the groups. Additionally, the need for reoperation was determined. Results: MEL significantly improved JOA scores, lumbar VAS, and ODI over the 10-year postoperative period. Pre-operative characteristics and postoperative outcomes were not significantly different between the cohorts. Overall, 18.4% (9/49) of patients required reoperation during the follow-up period. The reoperation rate in the RR-LSS-positive (13.8%; 4/29) group was similar to that in the RR-LL-negative (15.0%; 3/20) group. Conclusions: MEL is effective for lumbar stenosis, with improved clinical outcomes up to 10 years following surgery. Selective MEL, addressing only symptomatic levels in multilevel stenosis, with residual remaining lumbar stenosis, is similarly effective without increased reoperation rates. Surgeons may consider more limited selective decompression in patients with multilevel stenosis, avoiding the risk and invasiveness of extensive procedures. Level of Evidence: Level III.

MRI grading of spinal stenosis is not associated with the severity of low back pain in patients with lumbar spinal stenosis.

BACKGROUND: Although lumbar spinal stenosis (LSS) often coexists with other degenerative conditions, few studies have fully assessed possible contributing factors for low back pain (LBP) in patients with LSS. The purpose of this study was to identify factors associated with the severity of LBP in patients with LSS. METHODS: The patients with neurogenic claudication caused by LSS, which was confirmed by magnetic resonance imaging (MRI) were included in this cross-sectional study. Data included ratings of LBP, buttock and leg pain, and numbness on a numerical rating scale (NRS), 36-item Short-Form Survey (SF-36) scores, muscle mass measured by bioelectrical impedance analysis, and radiographic measurements including lumbopelvic alignment and slippage. The severity of LSS, endplate defects, Modic endplate changes, intervertebral disc degeneration, and facet joint osteoarthritis were evaluated on MRI. Spearman correlation and multivariate linear regression analyses were used to examine the factors associated with the severity of LBP (NRS score). RESULTS: A total of 293 patients (135 male and 158 female, average age 72.6 years) were analyzed. LBP was moderately correlated with buttock and leg pain, and buttock and leg numbness. Significant but weak correlations were observed between LBP and body mass index, appendicular and trunk muscle mass, all domains of SF-36, pelvic tilt, total number of endplate defects and Modic endplate changes, and summary score of disc degeneration grading, but not severity or number of spinal stenoses. In the multivariate regression analysis, age, female sex, trunk muscle mass, diabetes, NRS buttock and leg pain, NRS buttock and leg numbness, SF-36 vitality, pelvic tilt, and total number of endplate defects were associated with the severity of LBP. CONCLUSIONS: Trunk muscle mass, lumbopelvic alignment, and endplate defects, but not severity of stenosis are partly associated with severity of LBP, but buttock and leg pain and buttock and leg numbness have strongest relationships with LBP in patients with LSS.

Importance of physiological age in determining indications for adult spinal deformity surgery in patients over 75 years of age: a propensity score matching analysis.

PURPOSE: Physiologically, people age at different rates, which leads to a discrepancy between physiological and chronological age. Physiological age should be a priority when considering the indications for adult spinal deformity (ASD) surgery. The primary objective of this study was to determine the characteristics of the postoperative course, surgical outcomes, and complication rates to extend the healthy life expectancy of older ASD patients (≥ 75 years). The secondary objective was to clarify the importance of physiological age in the surgical treatment of older ASD patients, considering frailty. METHODS: A retrospective review of 109 consecutive patients aged ≥ 65 years with symptomatic ASD who underwent a corrective long fusion with lateral interbody fusion from the lower thoracic spine to the pelvis from 2015 to 2019 was conducted. Patients were classified into two groups according to age (group Y [65-74 years], group O [≥ 75 years]) and further divided into four groups according to the ASD-frailty index score (Y-F, Y-NF, O-F, and O-NF groups). To account for potential risk factors for perioperative course characteristics, complication rates, and surgical outcomes, patients from the database were subjected to propensity score matching based on sex, BMI, and preoperative sagittal spinal alignment (C7 sagittal vertical axis, pelvic incidence-lumbar lordosis, and pelvic tilt). Clinical outcomes were evaluated 2 years postoperatively, using three patient-reported outcome measures of health-related quality of life: the Oswestry Disability Index, Scoliosis Research Society questionnaire (SRS-22), and Short Form 36 (SF-36). Additionally, the postoperative time-to-first ambulation, as well as minor, major, and mechanical complications, were evaluated. RESULTS: In the comparison between Y and O groups, patients in group O were at a higher risk of minor complications (delirium and urinary tract infection). In contrast, other surgical outcomes of group O were comparable to those of group Y, except for SRS-22 (satisfaction) and time to ambulation after surgery, with better outcomes in Group O. Patients in the O-NF group had better postoperative outcomes (time to ambulation after surgery, SRS-22 (function, self-image, satisfaction), SF-36 [PCS]) than those in the Y-F group. CONCLUSIONS: Older age warrants monitoring of minor complications in the postoperative management of patients. However, the outcomes of ASD surgery depended more on frailty than on chronological age. Older ASD patients without frailty might tolerate corrective surgery and have satisfactory outcomes when minimally invasive techniques are used. Physiological age is more important than chronological age when determining the indications for surgery in older patients with ASD.

Supervised physical therapy versus surgery for patients with lumbar spinal stenosis: a propensity score-matched analysis.

BACKGROUND: Previous studies comparing surgical with nonsurgical treatment for lumbar spinal stenosis (LSS) reported that surgery is superior to nonsurgical treatments, but intensive and adequate volume of physical therapy were rarely performed. The purpose of this study was to compare the 1-year follow-up outcomes of patients with LSS treated with supervised physical therapy or surgery using propensity score-matched analysis. METHODS: A total of 224 patients with LSS who received supervised physical therapy (n = 38) or surgery (n = 186) were included, of which 66 were matched on baseline demographics, radiological findings, and patient-reported outcomes. The physical therapy group received supervised physical therapy twice weekly for 6 weeks. The physical therapy sessions included manual therapy, individually tailored exercises, cycling, and body-weight supported treadmill walking. The surgery group underwent decompression surgery with or without spinal fusion. A propensity score analysis was performed using a one-to-one nearest neighbor approach. RESULTS: The surgery group showed greater improvements in Zurich claudication questionnaire symptom severity and physical function, SF-36 physical functioning, bodily pain, and mental health, but had more severe stenosis and symptoms and mental health problems than the physical therapy group at baseline (P <  0.05). After propensity score matching, there were no significant differences in baseline characteristics, and all clinical outcomes at 1 year, except for a higher percentage of responders achieving minimum clinically important difference in the role-emotional subscale of SF-36 in the surgery group (P <  0.05). CONCLUSIONS: When baseline characteristics were considered, supervised physical therapy yielded similar effects to lumbar surgery. These results suggest that supervised physical therapy is preferred over surgery as first-choice treatment, to prevent complications and to minimize health care costs, especially in mild to moderate cases of LSS.

Endplate Deficits and Posterior Wall Injury Are Predictive of Prolonged Back Pain after Osteoporotic Vertebral Body Fracture.

Introduction: Osteoporotic vertebral compression fracture (OVCF) in the elderly is a major public health concern. This retrospective case-control study aimed to determine the difference in interobserver reliability between radiography, magnetic resonance imaging (MRI), and computed tomography (CT), respectively, and whether CT radiological findings can predict prolonged back pain at 2 weeks after OVCFs. Methods: Patients were divided into the prolonged back pain group or the recovered back pain group depending on the numerical rating scale at 2 weeks after admission. Radiography, MRI, and CT images were classified on the basis of conventions described by previous classifications. Interobserver reliability was calculated on images rated by two board-certified spine surgeons. Multivariate logistic regression models were used to evaluate whether the presence or absence of anterior wall injury, endplate deficit, posterior wall injury, lateral wall injury, or intervertebral disc deficit on CT was predictive of prolonged back pain. Results: Of the 130 patients, 89 cases (68.5%) involved prolonged back pain at 2 weeks after admission. Neither average age (79.8 vs. 80.1 years, respectively) nor duration to initial consultation (9.4 vs. 6.4 days, respectively) differed significantly between the prolonged and recovered back pain groups. Interobserver reliability was 0.51, 0.77 (0.67-0.86), and 0.82 (0.72-0.92) for radiography, MRI, and CT, respectively. After adjusting for confounding factors such as age, sex, duration to initial consultation, and extent of OVCF, the multivariate analysis showed that the presence of endplate deficit and posterior wall injury was a significant predictive factor for prolonged back pain (odds ratio [OR] 8.5, area under the curve (AUC); 0.79 and OR 2.5, AUC 0.72), respectively. Conclusions: Good reliability assessments of CT-based evaluations were noted. After a detailed novel CT evaluation at initial presentation, the presence of an endplate deficit and posterior wall injury was the significant risk factor for prolonged back pain at 2 weeks after an OVCF.

Is anterior decompression and fusion more beneficial than laminoplasty for K-line (+) cervical ossification of the posterior longitudinal ligament? An analysis using propensity score matching.

OBJECTIVE: It is unclear whether anterior cervical decompression and fusion (ADF) or laminoplasty (LMP) results in better outcomes for patients with K-line-positive (+) cervical ossification of the posterior longitudinal ligament (OPLL). The purpose of the study is to compare surgical outcomes and complications of ADF versus LMP in patients with K-line (+) OPLL. METHODS: The study included 478 patients enrolled in the Japanese Multicenter Research Organization for Ossification of the Spinal Ligament and who underwent surgical treatment for cervical OPLL. The patients who underwent anterior-posterior combined surgery or posterior decompression with instrumented fusion were excluded. The patients with a follow-up period of fewer than 2 years were also excluded, leaving 198 patients with K-line (+) OPLL. Propensity score matching was performed on 198 patients with K-line (+) OPLL who underwent ADF (44 patients) or LMP (154 patients), resulting in 39 pairs of patients based on the following predictors for surgical outcomes: age, preoperative Japanese Orthopaedic Association (JOA) score, C2-7 angle, and the occupying ratio of OPLL. Clinical outcomes were assessed 1 and 2 years after surgery using the recovery rate of the JOA score. Complications and reoperation rates were also investigated. RESULTS: The mean recovery rate of the JOA score 1 year after surgery was 55.3% for patients who underwent ADF and 42.3% (p = 0.06) for patients who underwent LMP. Two years after surgery, the recovery rate was 53.4% for those who underwent ADF and 38.7% for LMP (p = 0.07). Although both surgical procedures yielded good results, the mean recovery rate of JOA scores tended to be higher in the ADF group. The incidence of surgical complications, however, was higher following ADF (33%) than LMP (15%; p = 0.06). The reoperation rate was also higher in the ADF group (15%) than in the LMP group (0%; p = 0.01). CONCLUSIONS: Clinical outcomes were good for both ADF and LMP, indicating that ADF and LMP are appropriate procedures for patients with K-line (+) OPLL. Clinical outcomes of ADF 1 and 2 years after surgery tended to be better than LMP, but the analysis did not detect any significant difference in clinical outcomes between the groups. Conversely, patients who underwent ADF had a higher incidence of surgery-related complications. When considering indications for ADF or LMP, benefits and risks of the surgical procedures should be carefully weighed.

Anterior Decompression via a Single Posterior Approach Using the Ultrasonic Bone Scalpel for the Treatment of the Thoracic Segmental Ossification of Posterior Longitudinal Ligament: A Report of Three Cases.

INTRODUCTION: Thoracic myelopathy due to ossification of the posterior longitudinal ligament (T-OPLL) is an indication for surgical treatment because the symptom is usually progressive. The surgery for T-OPLL is technically challenging for several reasons. Various operational procedures were developed for dealing with T-OPLL. The anterior decompression through a single posterior approach is a procedure to achieve the complete decompression via the direct resection of the ossified lesion, especially for the beak-type OPLL. Previous reports showed better postoperative outcomes using this method than using other procedures. However, the difficulty and risk of complications are also reported because of the blinded resection of the lesion positioning ventrally to the dura mater. TECHNICAL NOTE: We describe a novel method using an anterior decompression through a single posterior approach using an ultrasonic bone scalpel. The following procedure is for a case of beak-type OPLL at the T5-6 level. The posterior elements at T2-9 were exposed after a median skin incision was created above a spinous process. First, pedicle screws were inserted bilaterally at T3-5 and T7-9. After the laminectomies and dekyphosis maneuver at T3-9, the spinal cord compression by OPLL was evaluated using intraoperative ultrasonography. After the slight medial facetectomy and pediclotomy at T5-6, the ultrasonic bone scalpel was inserted through the bilateral side of the spinal cord. The tip of the handpiece was angled to reach OPLL. The resection of OPLL was performed under intraoperative spinal cord monitoring. The intraoperative ultrasonography revealed the normal pulsation of the spinal cord and the space between the vertebral body and dura mater after completing the resection of OPLL. Posterolateral fusion was completed with local bone and harvested iliac crest. CONCLUSIONS: The anterior decompression through a single posterior approach using an ultrasonic bone scalpel is a safe and effective treatment of thoracic OPLL.

Comparison of laminoplasty and posterior fusion surgery for cervical ossification of posterior longitudinal ligament.

This prospective multicenter study, established by the Japanese Ministry of Health, Labour and Welfare and involving 27 institutions, aimed to compare postoperative outcomes between laminoplasty (LM) and posterior fusion (PF) for cervical ossification of the posterior longitudinal ligament (OPLL), in order to address the controversy surrounding the role of instrumented fusion in cases of posterior surgical decompression for OPLL. 478 patients were considered for participation in the study; from among them, 189 (137 and 52 patients with LM and PF, respectively) were included and evaluated using the Japanese Orthopaedic Association (JOA) scores, the JOA Cervical Myelopathy Evaluation Questionnaire (JOACMEQ), and radiographical measurements. Basic demographic and radiographical data were reviewed, and the propensity to choose a surgical procedure was calculated. Preoperatively, there were no significant differences among the participants in terms of patient backgrounds, radiographical measurements (K-line or cervical alignment on X-ray, OPLL occupation ratio on computed tomography, increased signal intensity change on magnetic resonance imaging), or clinical status (JOA score and JOACMEQ) after adjustments. The overall risk of perioperative complications was found to be lower with LM (odds ratio [OR] 0.40, p = 0.006), and the rate of C5 palsy occurrence was significantly lower with LM (OR 0.11, p = 0.0002) than with PF. The range of motion (20.91° ± 1.05° and 9.38° ± 1.24°, p < 0.0001) in patients who had PF was significantly smaller than in those who had LM. However, multivariable logistic regression analysis showed no significant difference among the participants in JOA score, JOA recovery rate, or JOACMEQ improvement at two years. In contrast, OPLL progression was greater in the LM group than in the PF group (OR 2.73, p = 0.0002). Both LM and PF for cervical myelopathy due to OPLL had resulted in comparable postoperative outcomes at 2 years after surgery.

Severity of Myelopathy is Closely Associated With Advanced Age and Signal Intensity Change in Cervical Ossification of the Posterior Longitudinal Ligament: A Prospective Nationwide Investigation.

STUDY DESIGN: Prospective, nationwide case series. OBJECTIVE: To identify preoperative factors associated with myelopathy and neurological impairment in patients with cervical ossification of the posterior longitudinal ligament (OPLL). SUMMARY OF BACKGROUND DATA: Various studies have reported clinical outcomes following the surgical treatment of OPLL. However, there has been no large-scale study of preoperative clinical features in patients with cervical OPLL. MATERIALS AND METHODS: Data were prospectively collected from 28 institutions nationwide in Japan. In total, 512 patients with neurological impairment caused by cervical OPLL requiring surgery were enrolled. Basic demographic and clinical data, including age, sex, diabetes status, body mass index, smoking history, and disease duration were collected. C2-7 lordotic angle, canal narrowing ratio, range of motion in flexion-extension at C2-7, and type of OPLL were evaluated on lateral radiographs to identify factors influencing the clinical features of patients with OPLL in whom surgery was planned. RESULTS: Complete documentation was available for 490 patients (362 male, 128 female). In total, 34 patients had the localized type, 181 had the segmental type, 64 had the continuous type, and 211 had the mixed type. Although there were no significant differences in age, body mass index, disease duration, Japanese Orthopedic Association (JOA) score, and lordotic angle at C2-7 according to the type of OPLL, significant differences were observed in a range of motion at C2-7 and the canal narrowing ratio among the 4 types. Multiple regression analysis revealed that the JOA score was significantly associated with age and signal intensity change on magnetic resonance imaging. CONCLUSIONS: This is the first large-scale, prospective, multicenter case series study to investigate factors influencing preoperative neurological status in patients with OPLL. Age and signal intensity change on magnetic resonance images were significantly associated with JOA score in patients requiring surgery. LEVEL OF EVIDENCE: Level II.

Endplate defects, not the severity of spinal stenosis, contribute to low back pain in patients with lumbar spinal stenosis.

BACKGROUND CONTEXT: It is controversial whether lumbar spinal stenosis (LSS) itself contributes to low back pain (LBP). Lower truncal skeletal muscle mass, spinopelvic malalignment, intervertebral disc degeneration, and endplate abnormalities are thought to be related to LBP. However, whether these factors cause LBP in patients with LSS is unclear. PURPOSE: To identify factors associated with LBP in patients with LSS. STUDY DESIGN/SETTING: Cross-sectional design. PATIENT SAMPLE: A total of 260 patients (119 men and 141 women, average age 72.8 years) with neurogenic claudication caused by LSS, as confirmed by magnetic resonance imaging (MRI). OUTCOME MEASURES: Ratings of LBP, buttock and leg pain, and numbness on a numerical rating scale (NRS), 36-Item Short Form Survey (SF-36) scores, muscle mass measured by bioelectrical impedance analysis, and radiographic measurements including slippage and lumbopelvic alignment. The severity of LSS, endplate defects, Modic endplate changes, intervertebral disc degeneration, and facet joint osteoarthritis were assessed on MRI. METHODS: The presence of LBP was defined as an NRS score ≥3. The demographic data, patient-reported outcomes, and radiological and MRI findings were compared between patients with and without LBP. Multivariate logistic regression analysis was used to identify the factors that were independently associated with the presence of LBP. RESULTS: There were significant differences between patients with and without LBP for buttock and leg pain and numbness on the NRS, general health on the SF-36, presence of endplate defects, presence of Modic changes, disc degeneration grading, and disc height grading (all p < .05). Multivariate logistic regression analysis showed significant associations between LBP and diabetes (OR 2.43; 95% CI 1.07-5.53), buttock and leg numbness on the NRS (OR 1.34; 95% CI 1.17-1.52), general health on the SF-36 (OR 0.97; 95% CI 0.95-0.99), and the presence of erosive endplate defects (OR 3.04; 95% CI 1.51-6.11) (all p < .05). CONCLUSIONS: These results suggest that LBP in patients with LSS should be carefully assessed not only for spinal stenosis but also clinical factors and endplate defects.