Kyphotic deformity following the loss of cervical lordosis can lead to unfavourable neurological recovery after cervical laminoplasty (CLP); therefore, it is essential to identify its risk factors. Recent studies have demonstrated that the dynamic parameters of the cervical spine, based on baseline flexion/extension radiographs, are highly useful to estimate the loss of cervical lordosis after CLP. However, it remains unclear whether such dynamic parameters can predict kyphotic deformity development after CLP. Hence, the present study aimed to investigate whether the dynamic parameters could predict kyphotic deformity in patients with cervical spondylotic myelopathy (CSM) after CLP. This retrospective study included 165 patients, consisting of 10 and 155 patients with and without cervical kyphosis of C2-C7 angle <= -10 degrees at the final follow-up period, respectively. Among the static and dynamic parameters of the cervical spine, greater cervical kyphosis during flexion (fC2-C7 angle) demonstrated the best discrimination between these two cohorts, with an optimal cutoff value of - 27.5 degrees. Meanwhile, greater gap range of motion (gROM = flexion ROM - extension ROM ) had the highest ability to predict a loss of >= 10 degrees in C2-C7 angle after CLP, with an optimal cutoff value of 28.5 degrees. This study suggests that in patients with CSM, fC2-C7 angle <= -25 degrees on baseline radiographs is a potential risk for kyphotic deformity after CLP. In clinical practice, the patients with this criterion (fC2-C7 angle <= -25 degrees) along with gROM >= 30 degrees are at high risk of developing significant kyphotic deformity after CLP.

CONTEXT:Patients with cervical compressive myelopathy (CCM) often complain of body balance problems, such as fear of falling and bodily unsteadiness. However, no accepted patient-reported outcome measures (PROMs) for this symptomatology exist. The Falls Efficacy Scale-International (FES-I) is one of the most widely used PROMs for evaluating impaired body balance in various clinical fields. OBJECTIVE:To examine reliability, validity, and minimum clinically important difference (MCID) of the FES-I for the evaluation of impaired body balance in patients with CCM. METHODS:Patients who underwent surgery for CCM were retrospectively reviewed. The FES-I was administered preoperatively and at 1 year postoperatively. Further, cJOA-LE score (subscore for lower extremities in the Japanese Orthopaedic Association score for cervical myelopathy) and stabilometric data, obtained at the same time points of the FES-I administration, were analyzed. Reliability was examined through internal consistency with Cronbach's alpha. Convergent validity was studied using correlation analysis. The MCID was estimated using anchor- and distribution-based methods. RESULTS:Overall, 151 patients were included for analysis. Cronbach's alpha coefficient was the acceptable value of 0.97 at both baseline and 1 year postoperatively. As for convergent validity, the FES-I had significant correlations with the cJOA-LE score and stabilometric parameters both at baseline and 1 year postoperatively. The MCID calculated using anchor- and distribution-based methods was 5.5 and 10, respectively. CONCLUSION:FES-I is a reliable and valid PROM to evaluate body balance problems for the CCM population. The established thresholds of MCID can help clinicians recognize the clinical significance of changes in patient status.

Study Design: A retrospective study. Objective: To verify the pathophysiology of dysphagia during the acute postoperative phase of anterior cervical surgery and to identify its predictive features, using ultrasonographic (US) examination for upper esophageal sphincter (UES). Summary of Background Data: There are no clinical studies investigating dysphagia after anterior cervical surgery, using US examination for UES. Materials and Methods: We enrolled patients who underwent anterior cervical spine surgery between August 2018 and March 2022. Dysphagia was evaluated using the Eating Assessment Tool-10 (EAT-10) questionnaires. The US examination was performed preoperatively and 2 weeks postoperatively. Three US parameters for morphologic measurements (outer diameter, inner diameter, and muscle thickness) and 4 for functional measurements (displacement, time to relax, passing duration, and time to contract) were assessed. To verify the pathophysiology of postoperative dysphagia, we examined the change in the ratios of US parameters (=US parameter 2 weeks postoperatively /US parameter at baseline ) and the existence of significant correlations with change in the EAT-10 score (=EAT-10 2 weeks postoperatively −EAT-10 at baseline ). To identify the predictive features, the baseline US parameters were compared between dysphagia (+) and dysphagia (−) groups. Results: A total of 46 patients (mean age, 61.3 y; 78.3% male) were included for analysis. A greater increase of the EAT-10 score after surgery was positively correlated with change ratios of the muscle thickness and time to contract and negatively with change ratio of the inner diameter. The dysphagia (+) group exhibited significantly greater inner diameter and smaller muscle thickness at baseline than the dysphagia (−) group. Conclusion: Dysphagia during the acute postoperative phase of anterior cervical surgery is caused by the physical narrowing of the inner lumen due to muscle thickening of the UES and sphincter contractile dysfunction. In addition, a baseline UES morphology characterized by a greater inner diameter and a thinner muscle layer is predictive of postoperative dysphagia.

BACKGROUND CONTEXT Cervical compressive myelopathy (CCM), caused by cervical spondylosis (cervical spondylotic myelopathy [CSM]) or ossification of the posterior longitudinal ligament (OPLL), is a common neurological disorder in the elderly. For moderate/severe CCM, surgical management has been the first-line therapeutic option. Recently, surgical management is also recommended for mild CCM, and a few studies have reported the surgical outcome for this clinical population. Nonetheless, the present knowledge is insufficient to determine the specific surgical outcome of mild CCM. PURPOSE To examine the surgical outcomes of mild CCM while considering the minimum clinically important difference (MCID). STUDY DESIGN Retrospective study. PATIENT SAMPLE Patients who underwent subaxial cervical surgery for CCM caused by CSM and OPLL between 2013 and 2022 were enrolled. OUTCOME MEASURES The Japanese Orthopedic Association score (JOA score) was employed as the clinical outcomes. Based on previous reports, the JOA score threshold to determine mild myelopathic symptoms was set at ≥14.5 points, and the MCID of the JOA score for mild CCM was set at 1 point. METHODS The patients with a JOA score of ≥14.5 points at baseline were stratified into the mild CCM and were examined while considering the MCID. The mild CCM cohort was dichotomized into the improvement group, including the patients with an achieved MCID (JOA score ≥1 point) or with a JOA score of 17 points (full mark) at 1 year postoperatively, and the nonimprovement group, including the others. Demographics, symptomatology, radiographic findings, and surgical procedure were compared between the two groups and studied using the receiver operating characteristic (ROC) curve. RESULTS Of 335 patients with CCM, 43 were stratified into the mild CCM cohort (mean age, 58.5 years; 62.8% male). Among them, 25 (58.1 %) patients were assigned to the improvement group and 18 (41.9 %) were assigned to the nonimprovement group. The improvement group was significantly younger than the nonimprovement group; however, other variables did not significantly differ. ROC curve analysis showed that the optimal cutoff point of the patient's age to discriminate between the improvement and nonimprovement groups was 58 years with an area under the curve of 0.702 (p=.015). CONCLUSIONS In the present study, the majority of patients with mild CCM experienced improvement reaching the MCID of JOA score at 1 year postoperatively. The present study suggests that for younger patients with mild CCM, especially those aged below 58 years, subjective neurological recovery is more likely to be obtained. Meanwhile, the surgery takes on a more prophylactic significance to halt disease progression for older patients. The results of this study can help in the decision-making process for this clinical population.

Backgrounds: For the surgical treatment of lumbar canal stenosis (LCS) due to spinal epidural lipomatosis (SEL), several studies have reported direct decompression, including fat debulking. However, none of these studies have mentioned indirect decompression for SEL. Here we report two cases in which indirect decompression with lateral interbody fusion (LIF) was effective in treating LCS due to SEL.Case description: Case 1 involves a 71-year-old male with LCS due to SEL at the L3/4 and L4/5 levels without a history of steroid usage. Case 2 involves a 60-year-old male with LCS due to SEL at the L2/3, L3/4, and L4/5 levels, who had been medicated with prednisolone (2.5 mg/day) and methotrexate (6 mg/week) for the treat-ment of remitting seronegative symmetrical synovitis with pitting edema syndrome. After oblique lateral interbody fusion and posterior fusion with percutaneous pedicle screw, the patients' symptoms disappeared immediately. Postoperative magnetic resonance imaging showed that the epidural fat had been successfully stretched, and the dura was decompressed.Conclusions: Indirect decompression with LIF could be a new surgical option for treating LCS due to SEL.

A retrospective multicenter study. Body mass index (BMI) is recognized as an important determinant of osteoporosis and spinal postoperative outcomes; however, the specific impact of BMI on surgery for osteoporotic vertebral fractures (OVFs) remains inconclusive. This retrospective multicenter study investigated the impact of BMI on clinical outcomes following fusion surgery for OVFs. 237 OVF patients (mean age, 74.3 years; 48 men and 189 women) with neurological symptoms who underwent spinal fusion were included in this study. Patients were grouped by World Health Organization BMI categories: low BMI (<18.5 kg/m2), normal BMI (≥18.5 and <25 kg/m2), and high BMI (≥25 kg/m2). Patients' backgrounds, surgical method, radiological findings, pain measurements, activities of daily living (ADL), and postoperative complications were compared after a mean follow-up period of 4 years. As results, the proportion of patients able to walk independently was significantly smaller in the low BMI group (75.0%) compared with the normal BMI group (89.9%; P = .01) and the high BMI group (94.3%; P = .04). Improvement in the visual analogue scale for leg pain was significantly less in the low BMI group than the high BMI group (26.7 vs 42.8 mm; P = .046). Radiological evaluation, the Frankel classification, and postoperative complications were not significantly different among all 3 groups. Improvement of pain intensity and ADL in the high BMI group was equivalent or non-significantly better for some outcome measures compared with the normal BMI group. Leg pain and independent walking ability after fusion surgery for patients with OVFs improved less in the low versus the high BMI group. Surgeons may want to carefully evaluate at risk low BMI patients before fusion surgery for OVF because poor clinical results may occur.

Study Design: This was a retrospective study. Objective: The objective of this study was to investigate the diagnostic utility of percutaneous ultrasonography (PUS) for postoperative epidural hematoma (EH) as a postoperative complication. Summary of Background Data: We investigated the usefulness of PUS for determining the need of surgical evacuation of postoperative EH by comparing the postoperative magnetic resonance imaging (MRI) and PUS of the spinal cord. Materials and Methods: This study included patients who underwent cervical laminoplasty using suture anchors. Regular MRI and PUS were performed 1 week postoperatively. Whenever the patients exhibited neurological deterioration, MRI and PUS were performed. The spinal cord decompression status was classified into 3 grades using MRI and PUS. The existence of spinal pulsation was determined by PUS. Results: One hundred thirty-one patients were investigated. The decompression status by MRI and PUS, and the pulsation status by PUS showed a correlation with neurological deterioration (P<0.001). Four cases showed postoperative neurological deterioration and required revision surgery. The decompression status in these cases was classified as “poor” by both MRI and PUS, and as “no-pulsation” by PUS pulsation. The sensitivity and specificity for neurological deterioration was 100% and 95.1% in MRI decompression, 100% and 92.9% in PUS decompression, and 100% and 99.2% in PUS pulsation, respectively. Conclusions: This is the first report that the disappearance of spinal pulsation was associated with neurological deterioration. PUS was useful in determining the need of surgical evacuation for postoperative EH. PUS should be the first choice of examination in the event of postoperative neurological deterioration following a cervical laminoplasty. When the disappearance of pulsation is confirmed, an additional hematoma evacuation surgery should be considered immediately without undertaking MRI. Level of Evidence: Level III.

BACKGROUND/CONTEXT:Kyphotic deformity after cervical laminoplasty (CLP) often leads to unfavorable neurological recovery due to insufficient indirect decompression of the spinal cord. Existing literature has described that segmental cervical instability is a contraindication for CLP because it is a potential risk factor for kyphotic changes after surgery; however, this has never been confirmed in any clinical studies. PURPOSE:To confirm whether segmental cervical instability was an independent risk factor for postoperative kyphotic change and to examine whether segmental cervical instability led to poor neurological outcomes after CLP for cervical spondylotic myelopathy (CSM). STUDY DESIGN/SETTING:A retrospective study PATIENT SAMPLE: Patients who underwent CLP for CSM between January 2013 and January 2021 with a follow-up period of ≥1 year were enrolled. OUTCOME MEASURES:Cervical radiographic measurements including C2-C7 lordosis (C2-7 angle), cervical sagittal vertical axis, C7 slope, flexion range of motion (fROM) and extension ROM (eROM) were assessed using neutral and flexion-extension views. Segmental cervical instability was classified into anterolisthesis (AL) of ≥2 mm displacement, retrolisthesis (RL) of ≥2 mm displacement, and translational instability (TI) of ≥3 mm translational motion. The amount of C2-7 angle loss at the follow-up period compared to the preoperative measurements was defined as cervical lordosis loss (CLL). Neurological outcomes were assessed using the recovery rate of the Japanese Orthopedic Association score (JOA-RR). METHODS:CLL was compared among patients with and without segmental cervical instability. Further, multiple linear regression model for CLL was built for the evaluation with adjustment of the reported risks, including cervical sagittal vertical axis, C7 slope, fROM, eROM, and patient age together with AL, RL, and TI, as independent variables. The JOA-RR was also compared between patients with and without segmental cervical instability. RESULTS:A total of 138 patients (mean age, 68.7 years; 65.9% male) were included in the analysis. AL, RL, and TI were found in 12 (8.7%), 33 (23.9%), and 16 (11.6%) patients, respectively. Comparisons among the groups showed that AL led to greater CLL; however, RL and TI did not. Multiple linear regression analysis revealed that greater CLL is significantly associated with greater fROM and smaller eROM (regression coefficient [β]=0.328, 95% confidence interval: 0.178 to 0.478, p<.001; β=-0.372, 95% confidence interval: -0.591 to -0.153, p=.001, respectively). However, there were no significant statistical associations in the AL, RL, and TI. Whereas, patients with AL tended to exhibit lower JOA-RR than those without AL (37.8% vs. 52.0%, p=.108). CONCLUSIONS:Segmental cervical instability is not the definitive driver for loss of cervical lordosis after CLP in patients with CSM; thus, is not a contraindication in and of itself. However, it is necessary to consider the indications for CLP, according to individual cases of patients with AL on baseline radiograph, which is a sign of poor neurological recovery.

Although the spontaneous regression of pseudotumors after posterior fusion has been reported, the predictive factors remain unclear. We examined the radiological features that predict for the regression of retro-odontoid pseudotumors after posterior fusion, with a specific focus on cyst formation.We included 28 patients with a diagnosis of retro-odontoid pseudotumor using preoperative magnetic resonance imaging. The radiographic parameters and pseudotumor thickness were measured pre- and postoperatively. The regression rate for each pseudotumor was calculated. The presence of a cyst around the retro-odontoid pseudotumor was investigated. If present, the cyst thickness was measured. To elucidate the predictors for the postoperative regression of pseudotumors, the patients were divided into 2 cohorts: the regression group with a regression rate >40% and the no-regression group with a regression rate of <40%. Multivariate logistic regression analysis, including the demographic data and preoperative radiographic parameters as independent variables, was performed.The mean pseudotumor size had decreased significantly from 8.8 ± 3.6 mm preoperatively to 5.3 ± 2.0 mm postoperatively (P < 0.0001). The mean regression rate was 35.9% during a magnetic resonance imaging follow-up period of 8.6 months (range, 6–12 months). Cystic lesions were noted in 10 patients (35.7%) preoperatively. The mean cyst size was 4.7 ± 1.9 mm. All cysts were located dorsal to the pseudotumors and were involved at the maximum spinal compression levels. Nevertheless, all the cysts had disappeared postoperatively. Multivariate logistic regression analysis revealed that the pseudotumor regression group had had a significantly greater proportion of cysts (57.1% vs. 14.3%; odds ratio, 11.7; P = 0.013).The presence of cystic lesions protruding from retro-odontoid pseudotumors might serve as a predictive factor for the spontaneous regression of pseudotumors after posterior fusion.

OBJECTIVE: Although the spontaneous regression of pseudotumors after posterior fusion has been reported, the predictive factors remain unclear. We examined the radiological features that predict for the regression of retro-odontoid pseudotumors after posterior fusion, with a specific focus on cyst formation. METHODS: We included 28 patients with a diagnosis of retro-odontoid pseudotumor using preoperative magnetic resonance imaging. The radiographic parameters and pseudotumor thickness were measured pre- and post-operatively. The regression rate for each pseudotumor was calculated. The presence of a cyst around the retro-odontoid pseudotumor was investigated. If present, the cyst thickness was measured. To elucidate the predictors for the postoperative regression of pseudotumors, the patients were divided into 2 cohorts: the regression group with a regression rate >40% and the no-regression group with a regression rate of <40%. Multivariate logistic regression analysis, including the demographic data and preoperative radiographic parameters as independent variables, was performed. RESULTS: The mean pseudotumor size had decreased significantly from 8.8 +/- 3.6 mm preoperatively to 5.3 +/- 2.0 mm postoperatively (P < 0.0001). The mean regression rate was 35.9% during a magnetic resonance imaging follow-up period of 8.6 months (range, 6-12 months). Cystic lesions were noted in 10 patients (35.7%) preoperatively. The mean cyst size was 4.7 +/- 1.9 mm. All cysts were located dorsal to the pseudotumors and were involved at the maximum spinal compression levels. Nevertheless, all the cysts had disappeared postoperatively. Multivariate logistic regression analysis revealed that the pseudotumor regression group had had a significantly greater proportion of cysts (57.1% vs. 14.3%; odds ratio, 11.7; P = 0.013). CONCLUSIONS: The presence of cystic lesions protruding from retro-odontoid pseudotumors might serve as a predictive factor for the spontaneous regression of pseudotumors after posterior fusion.

Background: Percutaneous ultrasonography (PUS) is used to evaluate the status of the spinal cord after cervical laminoplasty (CLP). This technique helps assess real-time movements of the spinal cord and provides immediate information regarding the decompression status. Additionally, it can also be utilized to evaluate the status of the spinal cord in various body positions and neck postures. This study aimed to examine changes in the decompression status of the spinal cord after CLP for cervical spondylotic myelopathy (CSM) in different body positions and neck postures using PUS and to assess whether these decompression statuses are related to clinical outcomes at each time point. Methods: The study included 66 consecutive participants with CSM who underwent double-door CLP with suture anchors. PUS was performed postoperatively at 2 weeks, 3 months, 6 months, and 1 year in sitting [neck flexion (Flexion), neutral (Neutral), and extension (Extension)] and supine (Supine) positions. The decompression status was classified into grade I (noncontact), grade II (contact and apart), and grade III (contact). Clinical outcomes were evaluated using Japanese Orthopaedic Association (JOA) scores. Results: The decompression status improved until 3 months postoperatively in all body positions and neck postures and was stable onwards. It changed depending on body positions and neck postures and was worse in Flexion and better in Supine at all postoperative time points. Participants with grade I decompression status in Supine had a significantly better recovery rate of JOA scores after 3 months, 6 months, and 1 year postoperatively than those with grade II thorn III decompression status. However, this significant relationship was not observed in each sitting position. Conclusions: The spinal cord after CLP is most decompressed in Supine. Sufficient and continuous restoration of the anterior subarachnoid space in supine position may indicate positive clinical outcomes after CLP. (C) 2021 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

STUDY DESIGN:Retrospective cohort study.OBJECTIVE:To clarify the poor patient satisfaction after lumbar spinal surgery in elderly patients.SUMMARY OF BACKGROUND DATA:As the global population continues to age, it is important to consider the surgical outcome and patient satisfaction in the elderly. No studies have assessed patient satisfaction in elderly patients undergoing surgical treatment and risk factors for poor satisfaction in elderly patients after lumbar spinal surgery.MATERIALS AND METHODS:A retrospective multicenter survey was performed in 169 patients aged above 80 years who underwent lumbar spinal surgery. Patients were followed up for at least 1 year after surgery. We assessed patient satisfaction from the results of surgery by using a newly developed patient questionnaire. Patients were assessed by demographic data, surgical procedures, complications, reoperation rate, pain improvement, and risk factors for poor patient satisfaction with surgery for lumbar spinal disease.RESULTS:In total, 131 patients (77.5%, G-group) were satisfied and 38 patients (22.5%, P-group) were dissatisfied with surgery. The 2 groups did not differ significantly in baseline characteristics and surgical data. Postoperative visual analog scale score for low back pain and leg pain were significantly higher in the P-group than in the G-group (low back pain: G-group, 1.7±1.9 vs. P-group, 5.2±2.5, P<0.001; leg pain: G-group, 1.4±2.0 vs. P-group, 5.5±2.6, P<0.001). Multivariate regression analysis revealed that postoperative vertebral fracture (P=0.049; odds ratio, 3.096; 95% confidence interval, 1.004-9.547) and reoperation (P=0.025; odds ratio, 5.692; 95% confidence interval, 1.250-25.913) were significantly associated with the patient satisfaction after lumbar spinal surgery.CONCLUSIONS:Postoperative vertebral fracture and reoperation were found to be risk factors for poor patient satisfaction after lumbar spinal surgery in elderly patients, which suggests a need for careful treatment of osteoporosis in addition to careful determination of surgical indication and procedure in elderly patients.LEVEL OF EVIDENCE:Level III.

Many neurological disorders can present similar symptomatology to degenerative cervical myelopathy (DCM) or myeloradiculopathy (DCMR). Therefore, to avoid misdiagnosis, it is important to recognise the differential diagnosis, which has been well described in previous literature. Additionally, DCM or DCMR can also coexist with other diseases that overlap some of its clinical manifestations, which may be overlooked before cervical surgery. Nevertheless, few studies have addressed this clinical situation. In clinical practice, the diagnosis of coexisting disease with DCM or DCMR would be typically made when some symptoms persist without improvement after cervical surgery. To inform the patients of this possibility preoperatively and arrive at the early diagnosis during the postoperative period, some knowledge of the possible coexisting diseases would be necessary. In this report, we reviewed 230 patients who underwent surgery for DCM or DCMR in an academic centre to examine the prevalence and kind of underlying disease that was overlooked preoperatively. The coexisting diseases relevant to their baseline symptoms were diagnosed only after cervical surgery in three patients (1.3%) and included amyotrophic lateral sclerosis, lung cancer and polymyalgia rheumatica. The overlapping symptoms were gait difficulty, scapular pain and neck pain, respectively. Surgeons should recognise that the coexisting disease with DCM or DCMR may be overlooked before cervical surgery because of overlapping symptomatology, although its prevalence is not certainly high. Further, when the specific symptom persisted without improvement after surgery for DCM or DCMR, the patient should be comprehensively examined, considering diverse pathological conditions, not only neurological disorders.

Study Design: A retrospective study. Objective: To investigate the effects of surgery on the subjective perception of bodily unsteadiness and the objective measurements of postural instability in patients with cervical compressive myelopathy (CCM). Summary of Background Data: Several studies have demonstrated that CCM patients have impaired postural stability and investigated its surgical outcomes. However, these studies have only objectively measured postural stability by using a stabilometer or three-dimensional motion capture system. There have been no studies examining the subjective perception of postural instability in CCM patients. Materials and Methods: We retrospectively reviewed patients who underwent decompressive surgery for CCM. The Fall Efficacy Scale-International (FES-I) and a self-prepared questionnaire were used to evaluate subjective perception of bodily unsteadiness. To objectively assess postural instability, a stabilometric analysis was performed with the following parameters: sway area (SwA, cm(2)), sway velocity (SwV, cm/s), and sway density (SwD, /cm). The evaluations were performed preoperatively, during the early postoperative period (3-6 mo postoperatively), and at 1-year postoperatively in patients with CCM. The evaluation results were compared with age-matched, sex-matched, and body mass index-matched healthy subjects. Results: We included 70 CCM patients and 36 healthy subjects in this study. In both the FES-I and self-prepared questionnaire, CCM patients reported significantly milder postoperative bodily unsteadiness. The stabilometric parameters were significantly improved during the postoperative period when compared with preoperative values. Nevertheless, neither the self-reported outcome measures nor stabilometric parameters of CCM patients reached the levels of those in healthy controls in the postoperative period. Conclusion: This was the first study to examine CCM surgical outcomes in terms of both subjective perception and objective postural instability. While both objective postural stability and subjective perception improved following decompressive surgery, they did not reach the levels seen in healthy participants.

Background Vertebroplasty with posterior spinal fusion (VP + PSF) is one of the most widely accepted surgical techniques for treating osteoporotic vertebral collapse (OVC). Nevertheless, the effect of the extent of fusion on surgical outcomes remains to be established. This study aimed to evaluate the surgical outcomes of short- versus long-segment VP + PSF for OVC with neurological impairment in thoracolumbar spine. Methods We retrospectively collected data from 133 patients (median age, 77 years; 42 men and 91 women) from 27 university hospitals and their affiliated hospitals. We divided patients into two groups: a short-segment fusion group (S group) with 2- or 3-segment fusion (87 patients) and a long-segment fusion group (L group) with 4- through 6-segment fusion (46 patients). Surgical invasion, clinical outcomes, local kyphosis angle (LKA), and complications were evaluated. Results No significant differences between the two groups were observed in terms of neurological recovery, pain scale scores, and complications. Surgical time was shorter and blood loss was less in the S group, whereas LKA at the final follow-up and correction loss were superior in the L group. Conclusion Although less invasiveness and validity of pain and neurological relief are secured by short-segment VP + PSF, surgeons should be cautious regarding correction loss.

Osteoporotic vertebral fracture (OVF) with nonunion or neurological deficit may be a candidate for surgical treatment. However, some patients do not show improvement as expected. Therefore, we conducted a nationwide multicenter study to determine the predictors for postoperative poor activity of daily living (ADL) in patients with OVF. We retrospectively reviewed the case histories of 309 patients with OVF who underwent surgery. To determine the factors predicting postoperative poor ADL, uni- and multivariate statistical analyses were performed. The frequency of poor ADL at final follow-up period was 9.1%. In univariate analysis, preoperative neurological deficit (OR, 4.1; 95% CI, 1.8–10.3; P < 0.001), perioperative complication (OR, 3.4; P = 0.006), absence of preoperative bone-modifying agent (BMA) administration (OR, 2.7; P = 0.03), and absence of postoperative recombinant human parathyroid hormone (rPTH) administration (OR, 3.9; P = 0.006) were significantly associated. In multivariate analysis, preoperative neurological deficit (OR, 4.6; P < 0.001), perioperative complication (OR, 3.4; P = 0.01), and absence of postoperative rPTH administration (OR, 3.9; P = 0.02) showed statistical significance. Preoperative neurological deficit, perioperative complication, and absence of postoperative rPTH administration were considered as predictors for postoperative poor ADL in patients with OVF. Neurological deficits and complications are often inevitable factors; therefore, rPTH is an important option for postoperative treatment for OVF. These slides can be retrieved under Electronic Supplementary Material.

OBJECTIVE:C5 palsy (C5P) is a known complication of cervical decompression surgery. The tethering effect of the C5 nerve root following the posterior shift of the spinal cord is the most accepted pathologic mechanism for C5P development; however, this mechanism cannot fully explain C5P by itself in clinical practice. Separately, some studies have suggested that preoperative severe spinal cord compression and postoperative morphological changes in the spinal cord affect C5P development; however, no previous study has quantitatively addressed these possibilities. The aim of this study was to examine whether spinal cord morphology and morphological restoration after surgery affect C5P development. METHODS:The authors reviewed consecutive patients with degenerative cervical myelopathy who underwent laminoplasty including the C3-4 and C4-5 intervertebral disc levels. All participants underwent MRI both preoperatively and within 4 weeks postoperatively. To assess the severity of spinal cord compression, the compression ratio (CR; spinal cord sagittal diameter/transverse diameter) was calculated. As an index of morphological changes in the spinal cord during the early postoperative period, the change rate of CR (CrCR, %) was calculated as CRwithin 4 weeks postoperatively/CRpreoperatively × 100. These measurements were performed at both the C3-4 and C4-5 intervertebral disc levels. The study cohort was divided into C5P and non-C5P (NC5P) groups; then, CR and CrCR, in addition to other radiographic variables associated with C5P development, were compared between the groups. RESULTS:A total of 114 patients (mean age 67.6 years, 58.8% men) were included in the study, with 5 and 109 patients in the C5P and NC5P groups, respectively. Preoperative CR at both the C3-4 and C4-5 levels was significantly lower in the C5P group than in the NC5P group (0.35 vs 0.44, p = 0.042 and 0.27 vs 0.39, p = 0.021, respectively). Patients with C5P exhibited significantly higher CrCR at the C3-4 level than those without (139.3% vs 119.0%, p = 0.046), but the same finding was not noted for CrCR at the C4-5 level. There were no significant differences in other variables between the groups. CONCLUSIONS:This study reveals that severe compression of the spinal cord and its greater morphological restoration during the early postoperative period affect C5P development. These findings could support the involvement of segmental cord disorder theory, characterized as the reperfusion phenomenon, in the pathomechanism of C5P, in addition to the tethering effect.

Intraspinal synovial cyst (ISC) is a well-documented pathology. It is sometimes found in the degenerative lumbar spine and can result in neurological disorders. ISC typically contains xanthochromic fluid, blood, inflammatory tissue, and/or osseous structures, enclosed by fibrous tissue. Regarding the treatment modalities, the effectiveness of both nonsurgical management, such as oral analgesics, needle aspiration, and intra-articular injection of corticosteroid drugs, and surgical management, have been reported. Previous studies have described that the ISC can contain gas, which is derived from the vacuum phenomenon of an adjacent facet joint; however, this clinical condition has never been systematically investigated because of its rarity. In the present report, we describe the case of a 68-year-old male with gas-containing ISC in the lumbar spine who was successfully treated with surgical management; additionally, we performed a literature review to discuss the decision-making process for cases of gas-containing ISC. Based on our findings and previous literature, we recommend that considering the peculiarity of the content of such lesions in addition to the ball-valve effect of a synovial cyst, prompt transition to surgical management would be pertinent when nonsurgical treatment cannot achieve satisfactory outcomes in such cases.

Kyphotic deformity is a rare but serious complication after cervical laminoplasty (CLP), and several studies have investigated its predictors. In these studies, a kyphotic Cobb angle of 0 degrees-5 degrees between C2 and C7 at a certain postoperative time-point was often used to detect kyphotic deformity. However, studies considering the amount of cervical lordosis loss compared to the preoperative measurement are scarce. This study aimed to elucidate risk factors for kyphotic change after CLP by comparing patients with and without marked loss of cervical lordosis postoperatively. The study population was divided into seven patients with and 92 patients without a loss of >10 degrees of the C2-7 angle during the follow-up period compared to the preoperative measurements [cervical lordosis loss (CLL) group and no CLL (NCLL) group, respectively]; demographic characteristics, surgical information, preoperative radiographic sagittal parameters of the cervical spine, and posterior paravertebral muscle morphology evaluated by magnetic resonance imaging were compared between two groups. A univariate analysis revealed that the CLL group had significantly greater flexion range of motion (fROM) than the NCLL group (43.0 degrees vs. 25.8 degrees, P < 0.001); however, no statistical significance was identified for other parameters. The fROM had a high capacity to discriminate between the CLL and NCLL groups (area under the receiver-operating characteristic curve, 0.880; P < 0.001; 95% confidence interval, 0.589-0.974) with an optimal cutoff point of 37 degrees. This study suggests that greater fROM is a risk factor for the development of kyphotic changes after CLP. For patients with preoperative fROM exceeding 40 degrees, CLP should be carefully indicated. (C) 2020 Elsevier Ltd. All rights reserved.