Impact of Skeletal Muscle Mass on Physical Function and Locomotive Syndrome of Pre- and Postoperative Adult Spinal Deformity.

Background: The purpose of this study is to identify the relationship between locomotive syndrome (LS) status, physical performance and limb and trunk skeletal muscle mass before and after surgery in adult spinal surgery (ASD) patients. Methods: A retrospective observational investigation of 63 consecutive patients with ASD who underwent spinal surgery was conducted. The total skeletal muscle mass of the arms and legs was considered a measure of the total appendicular skeletal muscle mass measured with whole-body dual-energy X-ray absorptiometry. All data pertaining to the physical performance tests and LS were collected preoperatively with follow-up one year postoperatively. Results: Gait speed, the one-leg standing test and the stand-up test were significantly improved one year after surgery compared to preoperative measurements. The lower extremity skeletal muscle mass predominantly influences physical function improvement including gait stride, one-leg standing and the stand-up test after ASD surgery. Conclusions: This study is the first to show that assessing lower extremity muscles prior to ASD surgery is useful in predicting postoperative recovery.

Early Versus Delayed Surgery for Elderly Traumatic Cervical Spinal Injury: A Nationwide Multicenter Study in Japan.

STUDY DESIGN: Retrospective multicenter study. OBJECTIVES: The effectiveness of early surgery for cervical spinal injury (CSI) has been demonstrated. However, whether early surgery improves outcomes in the elderly remains unclear. This study investigated whether early surgery for CSI in elderly affects complication rates and neurological outcomes. METHODS: This retrospective multicenter study included 462 patients. We included patients with traumatic acute cervical spinal cord injury aged ≥65 years who were treated surgically, whereas patients with American Spinal Injury Association (ASIA) Impairment Scale E, those with unknown operative procedures, and those waiting for surgery for >1 month were excluded. The minimum follow-up period was 6 months. Sixty-five patients (early group, 14.1%) underwent surgical treatment within 24 hours, whereas the remaining 397 patients (85.9%) underwent surgery on a standby basis (delayed group). The propensity score-matched cohorts of 63 cases were compared. RESULTS: Patients in the early group were significantly younger, had significantly more subaxial dislocations (and fractures), tetraplegia, significantly lower ASIA motor scores, and ambulatory abilities 6 months after injury. However, no significant differences in the rate of complications, ambulatory abilities, or ASIA Impairment Scale scores 6 months after injury were observed between the matched cohorts. At 6 months after injury, 61% of the patients in the early group (25% unsupported and 36% supported) and 53% of the patients in the delayed group (34% unsupported and 19% supported) were ambulatory. CONCLUSIONS: Early surgery is possible for CSI in elderly patients as the matched cohort reveals no significant difference in complication rates and neurological or ambulatory recovery between the early and delayed surgery groups.

The Utility and Appropriateness of Single-Position Circumferential Lumbar Interbody Fusion Using O-Arm-Based Navigation in the Novel Oblique Position.

PURPOSE: Single-position surgery with patients in a lateral position, which involves inserting percutaneous pedicular screws (PPS) and lateral interbody fusion (LIF) to avoid changing the position, has been reported. The purpose of the present study was to evaluate the utility and appropriateness of single-position LIF-PPS using O-arm-based navigation in the innovative oblique position. METHODS: This study involved a retrospective analysis of 92 consecutive patients with lumbar spondylolisthesis who underwent LIF-PPS using O-arm-based navigation. Thirty-five subjects demonstrated surgery with repositioning, as well as 24 in the lateral decubitus position, and 33 in the oblique during PPS, where the position was changed to the lateral decubitus position using bed rotation without resetting. We compared these three groups in terms of the surgery time, blood loss, and the accuracy of the screw placement. RESULTS: The operative time was significantly shorter in the single-position surgery, both in the lateral and oblique positions, compared to surgery in a dual position. The blood loss was significantly increased in the lateral position compared to the dual and oblique positions. The screw trajectory angle on the downside was significantly smaller in the lateral position, and the accuracy of the screw placement on the downside was significantly lower in the lateral position compared to the dual and oblique positions. CONCLUSION: Single-position surgery could reduce the average surgery time by about 60 min. The present study indicated the oblique position during PPS insertion might make single-position surgery more useful to improve the accuracy of PPS on the downside, with less blood loss.

Comparative Study for Characteristics of Locomotive Syndrome in Patients with Lumbar Stenosis and Adult Spinal Deformity.

INTRODUCTION: The differential diagnoses of lumbar spinal stenosis (LSS) and adult spinal deformity (ASD) have been demonstrated primarily using sagittal radiographic spinopelvic parameters. However, it is more important to know the differences in the characteristic clinical symptoms to make accurate treatment decisions. Recently, the relationship between spinal disease and Locomotive Syndrome (LS) has been reported. Additionally, the Geriatric Locomotive Function Scale-25 (GLFS-25) was reported to be a useful scale to evaluate disease severity and characteristic clinical symptoms in spinal disease. METHODS: Sixty-nine consecutive patients with ASD and 196 patients with LSS who underwent spinal surgery were included. Locomotive dysfunction was evaluated using the GLFS-25 questionnaire and physical performance tests including the two-step test and the stand-up test, measured preoperatively. The correlations between sagittal spinopelvic parameters of ASD and LS were examined. RESULTS: All subjects with lumbar degenerative disease in the present study were diagnosed with LS preoperatively. The severity of LS in patients with LSS and ASD were statistically similar. GLFS-25 scores in the mobility and community domain were similarly poor in both groups. Several scores in the domestic life and self-care domains were significantly worse in the ASD group. Question 20 of the GLFS-25, related to load-bearing tasks and housework, was significantly associated with a large pelvic incidence in ASD patients. CONCLUSIONS: Lumbar degenerative disease requiring surgery severely affects the LS of older people. ASD patients had more difficulty with load-bearing tasks and housework such as cleaning the yard, carrying heavy bedding, dressing, and bathing compared to LSS patients.

What Types of Strategies Are Effective in Lumbar Spine Surgery? Considering the Etiology, Imaging Findings, and Risk of Complications.

Lumbar spine surgery is commonly performed worldwide for the treatment of lumbar spinal disorder, and the surgery saves many patients with lower back and lower extremity pain [...].

Preoperative Symptom Duration Influences Neurological Recovery and Patient-Reported Outcome Measures After Surgical Treatment of Cervical Ossification of the Posterior Longitudinal Ligament.

STUDY DESIGN: A prospective multicenter study. OBJECTIVE: To investigate the effect of preoperative symptom duration on neurological recovery for the treatment of cervical ossification of the posterior longitudinal ligament (OPLL). SUMMARY OF BACKGROUND DATA: The optimal timing to perform surgery in the setting of cervical OPLL remains unknown. It is important to know the influence of symptom duration on postoperative outcomes to facilitate discussions regarding the timing of surgery. PATIENTS AND METHODS: The study included 395 patients (291 men and 104 women; mean age, 63.7 ± 11.4 yr): 204 were treated with laminoplasty, 90 with posterior decompression and fusion, 85 with anterior decompression and fusion, and 16 with other procedures. The Japanese Orthopedic Association (JOA) score and patient-reported outcomes of the JOA Cervical Myelopathy Evaluation Questionnaire were used to assess clinical outcomes preoperatively and 2 years after surgery. Logistic regression analysis was used to identify factors associated with the achievement of minimum clinically important difference (MCID) after surgery. RESULTS: The recovery rate was significantly lower in the group with symptom duration of ≥5 years compared with the groups with durations of <0.5 years, 0.5 to 1 year, and 1 to 2 years. Improvement of JOA Cervical Myelopathy Evaluation Questionnaire in the upper extremity function score ( P < 0.001), lower extremity function ( P = 0.039), quality of life ( P = 0.053), and bladder function ( P = 0.034) were all decreased when the symptom duration exceeded 2 years. Duration of symptoms ( P = 0.001), age ( P < 0.001), and body mass index ( P < 0.001) were significantly associated with the achievement of MCID. The cutoff value we established for symptom duration was 23 months (area under the curve, 0.616; sensitivity, 67.4%; specificity, 53.5%). CONCLUSIONS: Symptom duration had a significant impact on neurological recovery and patient-reported outcome measures in this series of patients undergoing surgery for cervical OPLL. Patients with symptom duration exceeding 23 months may be at greater risk of failing to achieve MCID after surgery. LEVEL OF EVIDENCE: 3.

Factors Associated With Loss of Cervical Lordosis After Laminoplasty for Patients With Cervical Ossification of the Posterior Longitudinal Ligament: Data From a Prospective Multicenter Study.

STUDY DESIGN: A prospective multicenter study. OBJECTIVE: The objective of this study was to investigate the incidence of loss of cervical lordosis after laminoplasty for cervical ossification of the posterior longitudinal ligament (OPLL). We also sought to determine associated risk factors and the relationship with patient-reported outcomes. SUMMARY OF BACKGROUND DATA: Loss of cervical lordosis is a sequelae often observed after laminoplasty, which may adversely impact surgical outcomes. Cervical kyphosis, especially in OPLL, is associated with reoperation, but risk factors and relationship to postoperative outcomes remain understudied at this time. MATERIALS AND METHODS: This study was conducted by the Japanese Multicenter Research Organization for Ossification of the Spinal Ligament. We included 165 patients who underwent laminoplasty and completed Japanese Orthopaedic Association (JOA) score or Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaires (JOACMEQ), as well as Visual Analog Scales (VAS) for pain, with imaging. The participants were divided into two groups: those with loss of cervical lordosis of >10° or 20° after surgery and those without loss of cervical lordosis. A paired t test was applied to evaluate the association between changes in cervical spinal angles, range of motion, and cervical JOA and VAS scores before and at 2 years postoperatively. Mann-Whitney U test was used for JOACMEQ. RESULTS: Postoperative loss of cervical lordosis >10° and >20° was observed in 32 (19.4%) and 7 (4.2%), respectively. JOA, JOACMEQ, and VAS scores were not significantly different between those with, and without, loss of cervical lordosis. Preoperative small extension range of motion (eROM) was significantly associated with postoperative loss of cervical lordosis, and the cutoff values of eROM were 7.4° [area under the curve (AUC): 0.76] and 8.2° (AUC: 0.92) for loss of cervical lordosis >10° and >20°, respectively. A large occupation ratio of OPLL was also associated with loss of cervical lordosis, with a cutoff value of 39.9% (AUC: 0.94). Laminoplasty resulted in functional improvement in most patient-reported outcomes; however, neck pain and bladder function tended to become worse postoperatively in cases with postoperative loss of cervical lordosis >20°. CONCLUSIONS: JOA, JOACMEQ, and VAS scores were not significantly different between those with, and without, loss of cervical lordosis. Preoperative small eROM and large OPLL may represent factors associated with loss of cervical lordosis after laminoplasty in patients with OPLL.

Clinical differences in preoperative symptoms and surgical outcomes between early and late-teen patients with Lenke type 5C adolescent idiopathic scoliosis.

PURPOSE: This study aimed to compare the clinical features and postoperative outcomes in patients with Lenke type 5C AIS in the early and late teens. METHODS: The study included eligible patients with AIS aged < 20 years with Lenke type 5C curves who underwent selective thoracolumbar/lumbar (TL/L) fusion. The patients were divided into two groups according to the age: younger (11-15 years) and older (16-19 years). Demographic data, radiographic parameters, and 22-item scoliosis research society questionnaire (revised) (SRS-22r) scores were compared. RESULTS: Seventy-three (female: 69, male: 4, mean age: 15.1 years) patients were included. There were 45 and 28 patients in the younger and older groups, respectively. The older group exhibited a significantly smaller TL/L curve than the younger group, whereas no between-group differences were identified regarding curve flexibility and fusion length. The change in coronal balance and subjacent disc angle from preoperative to 2 years after surgery was significantly greater in the younger group, although each curve was equally corrected. Preoperative SRS-22r scores in the older group were significantly worse; however, they improved to the level of the younger group at 2 years after surgery. Postoperative coronal malalignment was observed in six patients (21.4%) in the older group, whereas no cases in the younger group (p < 0.05). CONCLUSION: In patients with Lenke type 5C AIS, we showed that late teens had significantly worse SRS-22r scores than did early teens. Postoperative coronal malalignment was frequently observed in the late teens due to the reduced ability of compensation by subjacent disc wedging.

Comparison of Surgical Outcomes of Anterior and Posterior Fusion Surgeries for K-line (-) Cervical Ossification of the Posterior Longitudinal Ligament: A Prospective Multicenter Study.

STUDY DESIGN: A prospective multicenter study. OBJECTIVE: The objective of this study is to compare the surgical outcomes of anterior and posterior fusion surgeries in patients with K-line (-) cervical ossification of the posterior longitudinal ligament (OPLL). SUMMARY OF BACKGROUND DATA: Although laminoplasty is effective for patients with K-line (+) OPLL, fusion surgery is recommended for those with K-line (-) OPLL. However, whether the anterior or posterior approach is preferable for this pathology has not been effectively determined. MATERIALS AND METHODS: A total of 478 patients with myelopathy due to cervical OPLL from 28 institutions were prospectively registered from 2014 to 2017 and followed up for two years. Of the 478 patients, 45 and 46 with K-line (-) underwent anterior and posterior fusion surgeries, respectively. After adjusting for confounders in baseline characteristics using a propensity score-matched analysis, 54 patients in both the anterior and posterior groups (27 patients each) were evaluated. Clinical outcomes were assessed using the cervical Japanese Orthopaedic Association and the Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire. RESULTS: Both approaches showed comparable neurological and functional recovery. The cervical range of motion was significantly restricted in the posterior group because of the large number of fused vertebrae compared with the anterior group. The incidence of surgical complications was comparable between the cohorts, but the posterior group demonstrated a higher frequency of segmental motor paralysis, whereas the anterior group more frequently reported postoperative dysphagia. CONCLUSIONS: Clinical improvement was comparable between anterior and posterior fusion surgeries for patients with K-line (-) OPLL. The ideal surgical approach should be informed based on the balance between the surgeon's technical preference and the risk of complications.

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.

Deep learning-based prediction model for postoperative complications of cervical posterior longitudinal ligament ossification.

PURPOSE: Postoperative complication prediction helps surgeons to inform and manage patient expectations. Deep learning, a model that finds patterns in large samples of data, outperform traditional statistical methods in making predictions. This study aimed to create a deep learning-based model (DLM) to predict postoperative complications in patients with cervical ossification of the posterior longitudinal ligament (OPLL). METHODS: This prospective multicenter study was conducted by the 28 institutions, and 478 patients were included in the analysis. Deep learning was used to create two predictive models of the overall postoperative complications and neurological complications, one of the major complications. These models were constructed by learning the patient's preoperative background, clinical symptoms, surgical procedures, and imaging findings. These logistic regression models were also created, and these accuracies were compared with those of the DLM. RESULTS: Overall complications were observed in 127 cases (26.6%). The accuracy of the DLM was 74.6 ± 3.7% for predicting the overall occurrence of complications, which was comparable to that of the logistic regression (74.1%). Neurological complications were observed in 48 cases (10.0%), and the accuracy of the DLM was 91.7 ± 3.5%, which was higher than that of the logistic regression (90.1%). CONCLUSION: A new algorithm using deep learning was able to predict complications after cervical OPLL surgery. This model was well calibrated, with prediction accuracy comparable to that of regression models. The accuracy remained high even for predicting only neurological complications, for which the case number is limited compared to conventional statistical methods.

Epidemiology of Cervical Fracture/Cervical Spinal Cord Injury and Changes in Surgical Treatment Modalities in Elderly Individuals During a 10-year Period: A Nationwide Multicenter Study in Japan.

STUDY DESIGN: Retrospective multicenter study. OBJECTIVES: To investigate changes over a 10-years period in the profile of cervical spine and spinal cord injuries among the elderly in Japan. METHODS: The current multicenter study was a retrospective analysis of inpatients aged ≥65 years, suffering cervical fracture (CF) and/or cervical spinal cord injury (CSCI). We analyzed 1413 patients' epidemiology (from 2010 to 2019). Moreover, 727 patients who underwent surgical treatment were analyzed in 2 groups: the early (2010-2014) and late period (2015-2019). RESULTS: Both the number of patients and number of surgical patients showed a significant increasing trend (P < .001), while the mean age, the distribution of injury levels and paralysis severity, and the proportion of surgical indications remained the same. The number of surgical patients doubled from 228 to 499 from the early to late periods. Posterior surgery was the most common approach (90.4%), instrumentation surgery with screws increased significantly, and the range of fusion was significantly longer in the late period (2.1 vs 2.7 levels, P = .001). Significantly worsening neurological symptoms were recorded in the late period (1.3% vs 5.8%, P = .006), with C5 palsy being the major one. Otherwise, perioperative, major, and other complications, including mortality, did not differ significantly in incidence. CONCLUSIONS: Both the number of elderly CF and/or CSCI patients and number of patients undergoing surgery increased dramatically over the decade without any change in profile. Instrumentation surgeries with screws increased, without an increase in systemic complications.

Factors affecting the quality of life in the chronic phase of thoracolumbar osteoporotic vertebral fracture managed conservatively with a brace.

BACKGROUND CONTEXT: Although osteoporotic vertebral fractures (OVFs) are the most common type of osteoporotic fracture, few reports have closely investigated the factors contributing to the quality of life (QOL) in the chronic phase after thoracolumbar OVFs using detailed radiographic evaluation. PURPOSE: This study aimed to identify factors associated with the QOL in the chronic phase after thoracolumbar OVF. DESIGN: Post hoc analysis of a prospective randomized study. PATIENT SAMPLE: Participants included 195 patients with fresh thoracolumbar OVF managed conservatively with a brace who were available for radiographic analysis 48 weeks after injury. OUTCOME MEASURES: The degree of QOL impairment at 48 weeks after thoracolumbar OVF was assessed using the Japanese three-level version of the EuroQol five-dimensional questionnaire (EQ-5D) score. METHODS: Univariate and multivariate regression analyses were used to evaluate the relationships between the QOL and radiographic factors. RESULTS: The univariate analysis showed that age, analgesic use, T10/L5 Cobb angle on magnetic resonance imaging (MRI), subsequent vertebral fracture, and nonunion were significantly associated with the EQ-5D score at 48 weeks after thoracolumbar OVF. The multiple regression analysis showed that nonunion, analgesic use, subsequent vertebral fracture, and sacral slope on MRI were independently associated with the EQ-5D score at 48 weeks after thoracolumbar OVF. Receiver operating characteristic analysis for the deterioration of QOL showed that the cutoff value for sacral slope on MRI was 35 degrees. CONCLUSIONS: This study demonstrated that nonunion, subsequent vertebral fracture, and lower sacral slope were independently associated with poorer QOL in the chronic phase of thoracolumbar OVF managed conservatively with a brace. Therefore, improving or preventing these factors in patients with thoracolumbar OVF in the chronic phase may improve the QOL of the affected patients.

Radiological Assessment of Postoperative Paraspinal Muscle Changes After Lumbar Interbody Fusion With or Without Minimally Invasive Techniques.

STUDY DESIGN: Retrospective cohort study. BACKGROUND: Percutaneous pedicle screws (PPS) have the advantage of being able to better preserve the paraspinal muscles when compared with a traditional open approach. However, the nature of changes in postoperative paraspinal muscle after damage by lumbar fusion surgery has remained largely unknown. It is clinically important to clarify and compare changes in paraspinal muscles after the various surgeries. OBJECTIVE: (1) To determine postoperative changes of muscle density and cross-sectional area using computed tomography (CT), and (2) to compare paraspinal muscle changes after posterior lumbar interbody fusion (PLIF) with traditional open approaches and minimally invasive lateral lumbar interbody fusions (LLIF) with PPS. METHODS: We included data from 39 consecutive female patients who underwent open PLIF and 23 consecutive patients who underwent single-staged treatment with LLIF followed by posterior PPS fixation at a single level (L4-5). All patients underwent preoperative, 6 months postoperative, and 1-year postoperative CT imaging. Measurements of the cross-sectional area (CSA) and muscle densities of paraspinal muscles were obtained using regions of interest defined by manual tracing. RESULTS: We did not find any decrease of CSA in any paraspinal muscles. We did find a decrease of muscle density in the multifidus at 1 year after surgery in patients in the PILF group, but not in those in LLIF/PPS group. CONCLUSIONS: One year after surgery, a significant postoperative decrease of muscle density of the multifidi was observed only in patients who underwent open PLIF, but not in those who underwent LLIF/PPS.

Is histopathological synovitis score a predictor of postoperative requirement for additional or alternative drug treatment in the patients with rheumatoid arthritis?

OBJECTIVES: Histopathological synovitis scoring is useful for assessing activity in patients with rheumatoid arthritis (RA) at sampling, but it is unclear whether it can be a predictor of future drug treatment. The purpose of this study was to examine whether histopathological synovitis score is a predictor of postoperative requirement for additional or alternative drug treatment after total knee arthroplasty (TKA). METHODS: Thirty patients with RA in whom synovial samples were obtained during TKA were included. Patients were divided into the drug treatment enhanced group (EG), which included patients who needed additional or alternative drug treatment within 1 year after TKA, and the drug treatment maintenance group (MG). The Rooney synovitis score (RSS) was compared between groups. Logistic regression analysis was performed to clarify prognostic factors for postoperative drug treatment change. RESULTS: The total RSS was significantly higher in the EG than in the MG (29.3 vs 15.1; P < .001). Multivariate analysis showed that total RSS and swollen joint counts were independent variable associated with postoperative requirement for additional or alternative drug treatment (P < .05). CONCLUSIONS: Histopathological synovitis scoring may predict requirement for additional or alternative drug treatment in patients with RA after TKA.

Tips and pitfalls to improve accuracy and reduce radiation exposure in intraoperative CT navigation for pediatric scoliosis: a systematic review.

BACKGROUND CONTEXT: An increasing number of medical centers are adopting an intraoperative computed tomography (iCT) navigation system (iCT-Navi) to provide three-dimensional navigation for pediatric scoliosis surgery. While iCT-Navi has been reported to provide higher pedicle screw (PS) insertion accuracy, it may also result in higher radiation exposure to the patient. What innovations and studies have been introduced to reduce radiation exposure and further improve PS insertion? PURPOSE: Evaluate the level of evidence and quality of papers while categorizing the tips and pitfalls regarding pediatric scoliosis surgery using iCT-Navi. Compare iCT-Navi with other methods, including preoperative CT navigation. STUDY DESIGN: Systematic review. PATIENT SAMPLE: Articles on pediatric scoliosis surgery with iCT-Navi published through to June 2022. OUTCOME MEASURES: PS perforation rate and patient intraoperative radiation dose. METHODS: Following PRISMA guidelines, the Cochrane Library, Google Scholar, and PubMed databases were searched for articles satisfying the criteria of iCT-Navi use and pediatric scoliosis surgery. The level of evidence and quality of the articles meeting the criteria were evaluated according to the guidelines of the North American Spine Society and American Academy of Orthopedic Surgeons, respectively. The articles were also categorized by theme and summarized in terms of PS insertion accuracy and intraoperative radiation dose. The origins and characteristics of five major classification methods of PS perforation grade were summarized as well. RESULTS: The literature search identified 811 studies, of which 20 papers were included in this review. Overall, 513 pediatric scoliosis patients (381 idiopathic, 44 neuromuscular, 39 neurofibromatosis type 1, 28 congenital, 14 syndromic, seven other) were evaluated for PS perforations among 6,209 iCT-Navi insertions. We found that 232 (3.7%) screws were judged as major perforations (G2 or G3), 55 (0.9%) screws were judged as dangerous deviations (G3), and seven (0.1%) screws were removed. There were no reports of neurovascular injury caused by PSs. The risk factors for PS perforation included more than six vertebrae distance from the reference frame, more than nine consecutive insertions, upper thoracic level, thinner pedicle, upper instrumented vertebra proximity, short stature, and female. The accuracy of PS insertion did not remarkably decrease when the radiation dose was reduced to 1/5 or 1/10 by altering the iCT-Navi protocol. CONCLUSIONS: iCT-Navi has the potential to reduce PS perforation rates compared with other methods. The use of low-dose radiation protocols may not significantly affect PS perforation rates. Although several risk factors for PS perforation and measures to reduce radiation dose have been reported, the current evidence is limited by a lack of consistency in classifying PS perforation and evaluating patient radiation dose among studies. The standardization of several outcome definitions is recommended in this rapidly developing field.

Prospective Investigation of Surgical Outcomes after Anterior Decompression with Fusion and Laminoplasty for the Cervical Ossification of the Posterior Longitudinal Ligament: A Propensity Score Matching Analysis.

The ideal surgical strategy for cervical ossification of the posterior longitudinal ligament (OPLL) remains controversial due to the lack of high-quality evidence. Herein, we prospectively investigated the surgical outcomes of anterior cervical decompression with fusion (ADF) and laminoplasty (LAMP) with cervical OPLL. Three hundred patients were included in this study (ADF: n = 89; LAMP: n = 211 patients), and propensity score matching yielded 67 pairs of patients with ADF and LAMP, in which clinical outcomes were compared. Crude analysis revealed that the ADF group showed greater neurological recovery in cervical Japanese Orthopedic Association scores at two years, compared with that in the LAMP group (53.1% vs. 44.3%, p = 0.037). The ratio of minimum clinically important difference (MCID) success was significantly greater in the ADF group (59.6% vs. 43.6%, p = 0.016). Multivariate analysis showed that the factors affecting MCID success were age, body mass index, duration of symptoms, and choice of ADF. In the 1:1 matched analysis, neurological improvement was more favorable in the ADF group (57.2%) compared to the LAMP group (46.8%) at two years (p = 0.049). However, perioperative complications, such as dysphagia and graft-related complications, were more common in the ADF group.

Upper Extremity Skeletal Muscle Mass Asymmetry Exacerbated by Shoulder Imbalance in Lenke1A Adolescent Idiopathic Scoliosis.

Limb muscle strength asymmetry affects many physical abilities. The present study (1) quantified limb muscle asymmetry in patients with adolescent idiopathic scoliosis (AIS); (2) compared AIS patients with major thoracolumbar/lumbar (TL/L) or major thoracic (MT) curves; (3) examined correlations between limb muscle asymmetry and radiographic parameters. Patients with AIS with major TL/L curves (Lenke type 5C) and MT curves (Lenke Type 1A) who underwent posterior spinal fusion at our university hospitals were included. Patients with left hand dominance were excluded. Body composition was measured using whole-body dual-energy X-ray absorptiometry and asymmetry of left and right side skeletal muscles were evaluated. Upper extremity skeletal muscles on the dominant side were significantly larger than those on the nondominant side in both Lenke1A and 5C groups. The asymmetry of upper extremity skeletal muscles was significantly greater in the Lenke1A group than in the Lenke5C group. Additionally, the size of the asymmetry did not correlate with the magnitude of the major curve and rotational deformation but did correlate with a right shoulder imbalance in the Lenke1A group. These results suggest that in AIS with a constructive thoracic curve, right shoulder imbalance is an independent risk factor for upper extremity skeletal muscle asymmetry.

Translucent Zone Between Autograft and Endplate Two Months Postoperatively Is an Independent Predictor of Delayed Osseous Union in Elderly Patients With Posterior Lumbar Interbody Fusion Surgery.

Background Delayed union or pseudoarthrosis after posterior lumbar interbody fusion (PLIF) is associated with poor outcomes in health-related quality of life. Therefore, it is important to achieve earlier solid fusion for a successful clinical outcome after PLIF. A few authors reported that biomechanical factors may influence spinal fusion rates. The purpose of our retrospective study was to evaluate the independent predictors of delayed osseous union related to intraoperative procedures of PLIF, and to find ways to reduce delayed osseous union. Methods This was a retrospective study of a completed trial. We reviewed 66 elderly patients with osteoporosis after PLIF (all female, mean age 71 years, follow-up period over 6 months). Lumbar computed tomography scans at 2 months postoperatively were examined for the presence of a translucent zone between autograft and endplate (more than 50% of vertebral diameter), and autograft position with bone bridging (anterior, central, or posterior). Osseous union was assessed by using computed tomography 6 months postoperatively. Results Thirty-three patients (50%) showed complete osseous union, while 33 did not. A translucent zone between autograft and endplate two months postoperatively was observed in nine patients (27%) in the union group and in 23 (70%) in the nonunion group (p<0.01). Autograft position with bone bridging two months postoperatively was anterior, central, and posterior in 17 (52%), 30 (91%), and 20 patients (61%) in the union group, and in 12 (36%), 20 (61%), and seven patients (21%) in the nonunion group (p=0.22, p<0.01, and p<0.01), respectively. Multivariate logistic regression analysis showed that the presence of a translucent zone between autograft and endplate (odds ratio, 0.101; 95% confidence interval: 0.026-0.398; p<0.01) and teriparatide administration (odds ratio, 8.810; 95% confidence interval: 2.222-34.936; p<0.01) were independently associated with osseous union after PLIF. Conclusions A translucent zone between autograft and endplate at two months postoperatively independently predicted delayed osseous union within six months after PLIF. Complete osseous union rates were higher in patients with posterior bone bridging two months postoperatively than in those without. These findings apart from preoperative predictors of osseous union might serve as indicators of how intraoperative techniques affects osseous union enhancement.