池田 大樹

INTRODUCTION: Recently, patient satisfaction has gained prominence as a crucial measure for ensuring patient-centered care. Furthermore, patient satisfaction after lumbar spinal canal stenosis (LCS) surgery is an important metric for physician's decision of surgical indication and informed consent to patient. This study aimed to elucidate how patient satisfaction changed after LCS surgery to identify factors that predict patient dissatisfaction. METHODS: We retrospectively reviewed time-course data of patients aged ≥40 years who underwent LCS surgery at multiple hospitals. The participants completed the Zurich Claudication Questionnaire (ZCQ) and the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) before surgery and then 6 months and 1 year postsurgery. Patient satisfaction was categorized according to the postoperative score of the satisfaction domain of the ZCQ: satisfied, score ≤2.0; moderately satisfied, 2.0< score ≤2.5; and dissatisfied, score >2.5. RESULTS: The study enrolled 241 patients. Our data indicated a satisfaction rate of around 70% at 6 months and then again 1 year after LCS surgery. Among those who were dissatisfied 6 months after LCS surgery, 47.6% were more satisfied 1 year postsurgery. Furthermore, 86.2% of those who were satisfied 6 months after LCS surgery remained satisfied at 1 year. Multivariable analysis revealed that age (relative risk, 0.5; 95% confidence interval, 0.2-0.8) and preoperative score of psychological disorders on the JOABPEQ (relative risk, 0.2; 95% confidence interval, 0.03-0.08) were significantly associated with LCS surgery dissatisfaction. In addition, the receiver operating characteristic curve analysis revealed that the cutoff value for the preoperative score of psychological disorder of the JOABPEQ was estimated at 40 for LCS surgery dissatisfaction. CONCLUSIONS: Age and psychological disorders were identified as significant predictors of dissatisfaction, with a JOABPEQ cutoff value providing potential clinical applicability.

INTRODUCTION: Locomotive syndrome caused by degenerative musculoskeletal diseases is reported to improve with surgical treatment. However, it is unclear whether surgical treatment is effective for the locomotive syndrome developing in patients with degenerative cervical myelopathy (DCM). Thus, this study primarily aimed to longitudinally assess the change in locomotive syndrome stage before and after cervical spinal surgery for patients with DCM using the 25-question geriatric locomotive function scale (GLFS-25). A secondary objective was to identify factors associated with the postoperative improvement in the locomotive syndrome stage. METHODS: We retrospectively reviewed clinical data of patients undergoing cervical spine surgery at our institution from April 2020 to May 2022 who had answered the Japanese Orthopaedic Association Cervical Myelopathy Assessment Questionnaire, visual analog scale, and GLFS-25 preoperatively and at 6 months and 1 year postoperatively. We collected demographic data, medical history, preoperative radiographic parameters, presence or absence of posterior longitudinal ligament ossification, and surgical data. RESULTS: We enrolled 115 patients (78 men and 37 women) in the present study. Preoperatively, using the GLFS-25, 73.9% of patients had stage 3, 10.4% had stage 2, 9.6% had stage 1, 6.1% had no locomotive syndrome. The stage distribution of locomotive syndrome improved significantly at 6-months and 1-year postoperatively. The multivariable Poisson regression analysis revealed that better preoperative lower extremity function (relative risk: 3.0; 95% confidence interval: 1.01-8.8) was significantly associated with postoperative improvement in the locomotive syndrome stage. CONCLUSIONS: This is the first study to longitudinally assess the locomotive syndrome stage in patients with DCM using GLFS-25. Our results indicated that patients with DCM experienced significant improvement in the locomotive syndrome stage following cervical spine surgery. Particularly, the preoperative lower extremity function was significant in postoperative improvement in the locomotive syndrome stage.

INTRODUCTION: Frailty is an important factor in surgical outcomes. The current study aimed to evaluate the effect of preoperative frailty on postoperative outcomes in older patients with lumbar spinal canal stenosis (LSCS). METHODS: We retrospectively examined 209 patients aged ≥65 years who underwent surgery for LSCS. Health-related quality-of-life (HRQOL) tools, including the Roland-Morris Disability Questionnaire (RDQ), Zurich Claudication Questionnaire (ZCQ), and Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ), were used in the assessment conducted before surgery and at 6 months and 1 year after surgery. Frailty was categorized based on the 11-item modified frailty index (mFI-11). Patients with mFI-11 of 0, <0.21, and >0.21 were classified under the robust (R), pre-frailty (P), and frailty (F) groups, respectively. RESULTS: According to the mFI-11, 24, 138, and 47 patients were included in the R, P, and F groups, respectively. Regarding preoperative radiographic parameters, there was a remarkable increase in the sagittal vertical axis and a significant decrease in the development of lumbar lordosis with frailty progression. The preoperative scores of RDQ and ZCQ, and lumbar function, walking ability, social life, and psychological disorder domain scores of JOABPEQ differed significantly among these groups. The frequency of revision surgery was not higher in the F group than in the other groups. After adjustment for factors have shown different distributions among the three groups, the frequency of effective surgical cases did not show a clear trend among the three groups in all domains of the JOABPEQ. CONCLUSIONS: The preoperative HRQOL scores and the radiographic parameters of patients with LSCS worsened with frailty severity. However, frailty did not affect the rate of revision surgery and surgical efficacy in patients with LSCS. Although this study has limitations, our findings indicated that even LSCS patients with frailty can be considered for surgery if they have an indication for LSCS surgery.

CASE: An 85-year-old woman was transported to our institution due to difficulty in walking. Preoperative imaging showed spinal cord lesions indicative of spinal cord tumor at the T7-8 level, accompanied by T8 vertebral fracture. Intraoperatively, the spinal lesion was suspected to be an epidural abscess; therefore, the capsule was resected, and the abscess was drained. We added pedicle screw fixation at the T6-10 level. Postoperatively, the spinal cord lesion was definitively diagnosed as spinal epidural tuberculoma. CONCLUSION: Spinal epidural tuberculomas should be considered in the treatment of spinal cord lesions causing paralysis attributed to spinal cord compression.

PURPOSE: It is still unclear how lumbar spinal surgery affects the lipid metabolism of patients with lumbar spinal disorders (LSDs) such as lumbar spinal canal stenosis and lumbar disk herniation. The present study aimed to assess the impact of lumbar spinal surgery on lipid metabolism in patients with LSDs and clarify the factors associated with changes in visceral fat (VF) accumulation before and after lumbar spinal surgery. METHODS: Consecutive patients with lumbar spinal surgery for LSDs were prospectively included. Abdominal computed tomography images and blood examination of the participants were evaluated before surgery and at 6 months and 1 year after surgery. The cross-sectional VF area (VFA) was measured at the level of the navel using computed tomography images. Blood examination items included triglycerides and high-density lipoprotein (HDL). RESULTS: The study enrolled a total of 138 patients. Female patients with LSDs had significantly increased VFA and serum triglyceride levels after lumbar spinal surgery. On multivariable analysis, the group with > 100 cm2 of preoperative VFA and a postoperative decrease in VFA had a significantly worse preoperative walking ability based on the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (relative risk 2.1; 95% confidence intervals 1.1-4.1). CONCLUSIONS: The present study demonstrated that patients with LSDs did not necessarily improve their lipid metabolism after lumbar spinal surgery. Instead, female patients with LSDs had significantly deteriorated lipid metabolism after lumbar spinal surgery. Finally, a worse preoperative walking ability was associated with the improvement in excess VF accumulation after lumbar spinal surgery.

Background and Objectives: There are several advantages of using lateral lumbar interbody fusion (LLIF) for correction surgeries for adult spinal deformity (ASD); however, we currently have unresolved new issues, including occasional anterior longitudinal ligament (ALL) rupture during the posterior correction procedure. When LLIF was initially introduced, only less lordotic cages were available and ALL rupture was more frequently experienced compared with later periods when more lordotic cages were available. We performed finite element analysis (FEA) regarding the mechanism of ALL rupture during a posterior correction procedure. Methods: A spring (which mimics ALL) was introduced at the location of ALL in the FEA and an LLIF cage with two different lordotic angles, 6 and 12 degrees (6DC/12DC), was employed. To assess the extent of burden on the ALL, the extension length of the spring during the correction procedure was measured and the location of the rotation center was examined. Results: We observed a significantly higher degree of length extension of the spring during the correction procedure in the FEA model with 6DC compared with that of 12DC. We also observed that the location of the rotation center was shifted posteriorly in the FEA model with 6DC compared with that of 12DC. Conclusions: It is considered that the posterior and rostral edge of the less lordotic angle cage became a hinge, and the longer lever arm increased the burden on ALL as the principle of leverage. It is important to use an LLIF cage with a sufficient lordotic angle, that is compatible with the degree of posterior osteotomy in ASD correction.

OBJECTIVES: Although cervical spondylotic myelopathy (CSM) has a marked impact on locomotive function, few studies have evaluated this relationship in terms of locomotive syndrome. Thus, we assessed (i) the stages of locomotive syndrome in preoperative CSM patients using the 25-question geriatric locomotive function scale (GLFS-25), (ii) the correlation between GLFS-25 scores and the Japanese orthopaedic association (JOA) scores or the JOA cervical myelopathy evaluation questionnaire (JOACMEQ) scores, and (iii) the factors associated with stage 3 locomotive syndrome in preoperative CSM patients. METHODS: We used clinical data from 107 patients scheduled for cervical spinal surgery for CSM. Data were collected prior to surgery, and included age, gender, body mass index, medical history, JOA score, and JOACMEQ and GLFS-25 scores. RESULTS: Of the included CSM patients, 93.5% were diagnosed with locomotive syndrome, of whom 77.6% were stage 3 according to GLFS-25 evaluation. For the correlation between GLFS-25 and JOA or JOACMEQ, the upper and lower extremity function scores of JOACMEQ and the JOA were strongly inversely correlated with the GLFS-25 score. Finally, multivariate analysis suggested that severe lower extremity status in the JOACMEQ was significantly associated with stage 3 locomotive syndrome in preoperative CSM patients. CONCLUSIONS: Using the GLFS-25, we found that lower extremity status had the strongest association with stage 3 locomotive syndrome in preoperative CSM patients. These findings are useful for preventing CSM patients from requiring future nursing care.

Background and Objectives: Modic type 1 is known to be associated with lower back pain (LBP), but at present, a treatment has not been fully established. Meanwhile, platelet-rich plasma (PRP) has been used for tissue regeneration and repair in the clinical setting. There is no clinical PRP injection trial for the intervertebral disc of LBP patients with Modic type 1. Thus, this study aimed to verify PRP injection safety and efficacy in LBP patients with Modic type 1. As a preliminary experiment, two LBP cases with Modic type 1 are presented. Materials and Methods: PRP was administered intradiscally to two LBP patients with Modic type 1. PRP was obtained from the patients' anticoagulated blood. Primary endpoints were physical condition, laboratory data, and X-ray for safety evaluation. Secondary endpoints were pain scores using the visual analog scale (VAS), the Oswestry Disability Index (ODI), and the Roland-Morris Disability Questionnaire (RDQ) to evaluate PRP efficacy. The observation period was 24 weeks after the PRP injection. In addition, changes in Modic type 1 using MRI were evaluated. Results: This study assessed two LBP patients with Modic type 1. There were no adverse events in physical condition, laboratory data, or lumbar X-rays after injection. Follow-up MRI showed a decrease of high signal intensity on T2WI compared to before PRP administration. The pain scores tended to improve after the injection. Conclusions: PRP injection into the intervertebral disc of LBP patients with Modic type 1 might be safe and effective. This analysis will be continued as a prospective study to establish the efficacy.

CASE: Patients with myelopathy due to narrowing of the spinal canal with ossification of the ligamentum flavum (OLF) generally require surgical intervention, but surgical methods for OLF remain controversial. We discuss our experience regarding posterior fusion surgery with instrumentation for a patient with recurrent OLF at the same level after decompression surgery as well as describe the preoperative and postoperative course of this rare case. CONCLUSION: Posterior decompression and fusion surgery is recommended as revision surgery for recurrent OLF at the same level after decompression surgery. A detailed surgical planning should be developed before surgery.

STUDY DESIGN: Retrospective study. OBJECTIVES: The combination of oblique lateral interbody fusion (OLIF) with grade 2 posterior column osteotomy (PCO) is an effective treatment for adult spinal deformity. However, grade 2 PCO may lead to pseudoarthrosis because it involves complete removal of the bilateral posterior facet joints. The main study objective was to determine the achievement rate of anterior and posterolateral fusion resulting in circumferential fusion in patients who underwent combined OLIF and grade 2 PCO. METHODS: This retrospective study included consecutive patients who underwent OLIF and grade 2 PCO. The group comprised a long fusion group, with fusion from the thoracic level to the ilium, and a short fusion group, with fusion within the lumbar region. The OLIF with percutaneous pedicle screw insertion group was also used for reference. The Brantigan-Steffee-Fraser classification was used to assess interbody fusion and Lenke classification for assessment of posterolateral fusion. RESULTS: Sixty-six patients with 109 lumbar levels were included in the study. We observed 100% anterior fusion in all 3 groups. The fusion rate for posterolateral fusion between the OLIF-grade 2 PCO group was 97%, with very low (3%) non-circumferential fusion (pseudoarthrosis only at the osteotomy site). In most cases, solid posterolateral fusions (Lenke A) occurred within 24 months. CONCLUSIONS: The combination of OLIF and grade 2 PCO resulted in circumferential fusion for most (97%) of the cases within 24 months. OLIF and grade 2 PCO are considered a good combination treatment to achieve sufficient lumbar lordosis and solid bone fusion.

BACKGROUND: Although several causes of ligamentum flavum (LF) hypertrophy have been identified, the pathomechanisms underlying LF hypertrophy are not fully understood. Because collagen fibers are essential for the maintenance of LF tissues, characterization of the collagen composition of hypertrophied LF may help to elucidate the pathology of lumbar spinal canal stenosis (LCS). This study aimed to determine the association between the collagen composition and LF hypertrophy. METHODS: LF tissues were collected from 23 patients who underwent spinal decompression surgery for lumbar disorders. The cross-sectional area of LF was measured using the axial images of lumbar MRI. The expression of each collagen in human surgical samples was evaluated by real-time RT-PCR and immunohistochemical analysis. To investigate the impact of inflammatory cytokines on the expression of each collagen, we treated primary human LF cells with TNF-α or IL-1β. RESULTS: Real-time RT-PCR analysis and immunohistochemistry showed that of the 28 types of collagen, collagen type I, III, V, VI, VIII were highly expressed regardless of LF hypertrophy. In addition, we found the moderate correlation between the cross-sectional area of LF and the mRNA expression level of collagen type I, III, and VI. In vitro analysis showed that the mRNA expression of collagen type I, III, V, VI, and VIII was up-regulated by treatment with TNF-α and with IL-1β. CONCLUSION: Our results suggested that collagen type I, III, V, VI, and VIII were the main components of the LF extracellular matrix and that collagen type I, III, and VI may serve as useful markers of LF hypertrophy. These findings may contribute to the future development of diagnostic and treatment modalities for LF hypertrophy and even LCS.