The Impact of Frailty on Surgical Outcome of Patients with Lumbar Spinal Canal Stenosis.

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.

Intradiscal administration of autologous platelet-rich plasma in patients with Modic type 1 associated low back pain: A prospective pilot study.

Background: Various treatments for chronic low back pain (LBP) have been reported; among them, platelet-rich plasma (PRP) as a regenerative medicine has attracted much attention. Although Modic type 1 change (MC1) is associated with LBP, no treatment has been established so far. In addition, no studies have administered PRP to intervertebral discs (IVDs) in patients with LBP, targeting MC1 only. Thus, the purpose of this study was to determine the safety and efficacy of PRP administration to the IVDs in patients with MC1 experiencing LBP. Methods: PRP was injected intradiscally to 10 patients with MC1 experiencing LBP. Patients were followed prospectively for up to 24 weeks after primary administration. Physical condition, laboratory data, and lumbar x-ray images were evaluated for safety assessment. Furthermore, to evaluate the effectiveness of PRP, patient-reported outcomes were considered. In addition, changes in MC1 were assessed using magnetic resonance imaging (MRI). Results: There were no adverse events in the laboratory data or lumbar X-ray images after administration. The mean visual analog scale, which was 70.0 ± 13.3 before the treatment, significantly decreased 1 week after PRP administration and was 39.0 ± 28.8 at the last observation. Oswestry disability index and Roland Morris disability questionnaire scores promptly improved after treatment, and both improved significantly 24 weeks after PRP administration. Follow-up MRI 24 weeks after treatment showed a significant decrease in the mean high-signal intensity of fat-suppressed T2-weighted imaging from 10.1 to 7.90 mm2 compared with that before PRP administration. Conclusions: The safety and efficacy of PRP administration to the IVDs of patients with MC1 experiencing LBP were identified. Post-treatment MRI suggested improvement in inflammation, speculating that PRP suppressed inflammation and consequently relieved the patient's symptoms. Despite the small number of patients, this treatment is promising for patients with MC1 experiencing LBP. The study protocol has been reviewed and approved by the Certified Committee for Regenerative Medicine and the Japanese Ministry of Health, Labor and Welfare (Japan Registry of Clinical Trials [jRCT] No. jRCTb042210159).

Significance of Continuous Low-Dose Lenvatinib for the Treating of the Patients with Unresectable Thyroid Carcinoma.

The tyrosine kinase inhibitor lenvatinib has been confirmed as an effective treatment option for patients with unresectable thyroid carcinoma. We conducted a retrospective analysis of the significance of the effect of continued lenvatinib treatment for the longest duration possible at a reasonable daily dose and with a minimum discontinuation period in 42 patients with unresectable thyroid carcinoma treated with lenvatinib between 2015 and 2020. A Cox proportional hazard model-based analysis revealed that the overall survival of the patients treated with a <8 mg/day mean dose of lenvatinib was significantly better than that of the patients treated with 8-24 mg/day (hazard ratio [HR] 0.38 for 1.14-4.54 mg/day, and HR 0.01 for 4.56-7.97 mg/day) adjusted for various factors (e.g., sex, age, drug interruption period). The cumulative dose of lenvatinib administered tended to be higher in the patients treated with low doses (< 8 mg/day) than in the patients treated with relatively high doses (8-24 mg/day). Considering its adverse events, the continuation of lenvatinib treatment with an adequate daily dose and drug interruption may help prolong the survival of patients with unresectable thyroid carcinoma.

Nestin-expressing cells are mitotically active in the mammalian inner ear.

Nestin expression is associated with pluripotency. Growing evidence suggests nestin is involved in hair cell development. The objective of this study was to investigate the morphology and role of nestin-expressing cells residing in the early postnatal murine inner ear. A lineage-tracing nestin reporter mouse line was used to further characterize these cells. Their cochleae and vestibular organs were immunostained and whole-mounted for cell counting. We found Nestin-expressing cells present in low numbers throughout the inner ear. Three morphotypes were observed: bipolar, unipolar, and globular. Mitotic activity was noted in nestin-expressing cells in the cochlea, utricle, saccule, and crista. Nestin-expressing cell characteristics were then observed after hair cell ablation in two mouse models. First, a reporter model demonstrated nestin expression in a significantly higher proportion of hair cells after hair cell ablation than in control cochleae. However, in a lineage tracing nestin reporter mouse, none of the new hair cells which repopulated the organ of Corti after hair cell ablation expressed nestin, nor did the nestin-expressing cells change in morphotype. In conclusion, Nestin-expressing cells were identified in the cochlea and vestibular organs. After hair cell ablation, nestin-expressing cells did not react to the insult. However, a small number of nestin-expressing cells in all inner ear tissues exhibited mitotic activity, supporting progenitor cell potential, though perhaps not involved in hair cell regeneration.

Spinal Epidural Tuberculoma with Adjacent Vertebral Fracture: A Case Report.

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.

Association between frailty and locomotive syndrome in elderly patients with lumbar spinal stenosis: A retrospective longitudinal analysis.

AIMS: With the aging society worldwide, lumbar spinal stenosis (LSS) has become common, and its incidence has been increasing worldwide. Frailty and locomotive syndrome significantly overlap as disorders in older people. The current study aimed to validate the association between frailty and locomotive syndrome in patients with LSS. In particular, the involvement of frailty in locomotive syndrome following surgery was examined. METHODS: We retrospectively reviewed the time-course data of consecutive patients aged ≥65 years who underwent lumbar spinal surgery for LSS. The locomotive syndrome stages were determined using the 25-Question Geriatric Locomotive Function Scale: stage 0, score ≤6; stage 1, score ≥7; stage 2, score ≥16; and Stage 3, score ≥24. Robust, pre-frailty, and frailty were defined as a modified frailty index-11 score of 0, <0.21, and >0.21, respectively. RESULTS: This study included 234 patients. All patients except one were diagnosed with locomotive syndrome preoperatively. Approximately 24.8% of participants were diagnosed with frailty. LSS surgery improved locomotive syndrome regardless of frailty severity. Meanwhile, multivariable analysis indicated that frailty could significantly inhibit improvement in locomotive syndrome after surgery in old patients with LSS (estimated relative risk: 0.6; 95% confidence interval: 0.4-0.9). CONCLUSIONS: This study first assessed the association between locomotive syndrome and frailty in patients with LSS. Locomotive syndrome could be managed effectively with surgery regardless of frailty severity in old patients with LSS. However, our findings emphasize the need to screen for frailty preoperatively in this patient group. Geriatr Gerontol Int 2024; 24: 116-122.

Impact of surgical treatment on lipid metabolism in patients with lumbar spinal disorders: Prospective observational study.

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.

Elucidation of the Mechanism of Occasional Anterior Longitudinal Ligament Rupture with Posterior Correction Procedure for Adult Spinal Deformity Using LLIF-Finite Element Analysis of the Impact of the Lordotic Angle of Intervertebral LLIF Cage.

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.

Different solubilizing ability of cyclodextrin derivatives for cholesterol in Niemann-Pick disease type C treatment.

BACKGROUND: Niemann-Pick disease type C (NPC) is a fatal neurodegenerative disorder caused by abnormal intracellular cholesterol trafficking. Cyclodextrins (CDs), the most promising therapeutic candidates for NPC, but with concerns about ototoxicity, are cyclic oligosaccharides with dual functions of unesterified cholesterol (UC) shuttle and sink that catalytically enhance the bidirectional flux and net efflux of UC, respectively, between the cell membrane and the extracellular acceptors. However, the properties of CDs that regulate these functions and how they could be used to improve treatments for NPC are unclear. METHODS: We estimated CD-UC complexation for nine CD derivatives derived from native α-, ß-, and γ-CD with different cavity sizes, using solubility and molecular docking analyses. The stoichiometry and complexation ability of the resulting complexes were investigated in relation to the therapeutic effectiveness and toxicity of each CD derivative in NPC experimental models. FINDINGS: We found that shuttle and sink activities of CDs are dependent on cavity size-dependent stoichiometry and substituent-associated stability of CD-UC complexation. The ability of CD derivatives to form 1:1 and 2:1 complexes with UC were correlated with their ability to normalize intracellular cholesterol trafficking serving as shuttle and with their cytotoxicity associated with cellular UC efflux acting as sink, respectively, in NPC model cells. Notably, the ability of CD derivatives to form an inclusion complex with UC was responsible for not only efficacy but ototoxicity, while a representative derivative without this ability negligibly affected auditory function, underscoring its preventability. CONCLUSIONS: Our findings highlight the importance of strategies for optimizing the molecular structure of CDs to overcome this functional dilemma in the treatment of NPC.

Severity of locomotive syndrome in surgical cervical spondylotic myelopathy patients: a cross-sectional study.

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.

Outpatient ablation treatment with two doses of 30 mCi of radioactive iodine for non-low-risk papillary thyroid cancer.

Outpatient ablation therapy with low-dose radioactive iodine (RAI) is applied to non-low-risk papillary thyroid cancer patients due to a chronic shortage of inpatient RAI treatment wards in Japan. We used the maximum dosage available for outpatient therapy of 30 mCi of RAI for ablation and diagnostic (Dx) whole-body scintigraphy (WBS). This study aimed to examine the significance of the second dose of 30 mCi. DxWBS was performed 6 months after ablation, and assessment of success or failure was performed 12 months after ablation. A second WBS was performed in the remaining RAI accumulation cases in the neck on DxWBS. The criteria for successful ablation was negative cervical accumulation on WBS, thyroid stimulating hormone-suppressed thyroglobulin (sup-Tg) below 1.0 ng?/?mL, and no increase in thyroglobulin antibody (TgAb) level. At the time of DxWBS, 35?/?68 cases met the successful criteria, and 45 cases achieved success at assessment. Sup-Tg values decreased significantly after ablation and decreased further after DxWBS in successful ablation cases, whereas those were not changed in ablation failure cases. Findings indicated that RAI used in DxWBS had therapeutic effects. It makes sense to use 30 mCi for DxWBS, given the current difficulty of inpatient ablation therapy with high-dose RAI. J. Med. Invest. 70 : 17-21, February, 2023.

Bone wax technique for full-endoscopic lumbar laminotomy.

Hemostatic procedures in endoscopic spine surgery have not yet been established, especially in full-endoscopic spine surgery (FESS) performed under continuous irrigation, which has been a major concern for surgeons. Chu et al. had previously reported a technique to convey bone wax during full-endoscopic cervical spine surgery via intracorporeal route by using ball tip of the drill in 2018. However, to the best of our knowledge, there has been no report by surgeons to adopt bone wax as a hemostatic material in full-endoscopic lumbar surgery to date, probably because of difficulty in handling bone wax under continuous irrigation and through a narrow and long working channel in endoscope. We have renewed the bone wax technique (BWT) for hemostasis in FESS, improving its handling by introducing a nozzle applicator, without which the bone wax would stick to the working channel of the endoscope on the way to the bleeding target. This would result in significant loss of bone wax and repeated bone-wax contact would cause dirt build-up on the endoscope lens, which would then be pushed out from the wall of the working channel, thereby disturbing the laminectomy procedure and obfuscating the visual field. Technical details using nozzle-loaded bone wax have been demonstrated.

Impact of Lumbar Surgery on Pharmacological Treatment for Patients with Lumbar Spinal Canal Stenosis: A Single-Center Retrospective Study.

Treatment for lumbar spinal canal stenosis (LSCS) is mainly classified into conservative and surgical therapies. Among conservative therapies, pharmacological treatment is commonly prescribed for LSCS. Meanwhile, surgical treatment is the last option for LSCS. This study aimed to examine the impact of lumbar surgery on pharmacological treatment for patients with LSCS. Consecutive patients aged ≥ 40 years who underwent lumbar surgery for LSCS were identified. A total of 142 patients were retrospectively reviewed for preoperative and 6-month and 1-year postoperative LSCS medications. The results showed that the number of LSCS medications significantly decreased after lumbar surgery. The proportion of the patients taking non-steroidal anti-inflammatory drugs, pregabalin/mirogabalin, opioids, prostaglandin E1 analogs, and neurotropin was significantly decreased after lumbar surgery, but that of the patients taking mecobalamin, acetaminophen, and serotonin-noradrenalin reuptake inhibitors was not significantly changed. Additionally, around 15% of the participants showed an increase in LSCS medications even after lumbar surgery. Multivariable analysis revealed that individuals without improvements in walking ability (RR: 2.7, 95% CI: 1.3-5.9) or social life (RR: 2.3, 95% CI: 1.1-5.0) had a greater risk of a postoperative increase in LSCS medications. The study results may provide physicians with beneficial information on treatment for LSCS.

Efficacy of surgical treatment on polypharmacy of elderly patients with lumbar spinal canal stenosis: retrospective exploratory research.

BACKGROUND: Polypharmacy is a growing public health problem occurring in all healthcare settings worldwide. Elderly patients with lumbar spinal canal stenosis (LSS) who manifest low back and neuropathic pain and have a high frequency of comorbidity are predicted to take many drugs. However, no studies have reported polypharmacy in elderly patients with LSS. Thus, we aimed to review the polypharmacy among elderly LSS patients with elective surgeries and examine how the surgical treatment reduces the polypharmacy. METHODS: We retrospectively enrolled all the patients aged ≥ 65 years who underwent spinal surgery for LSS between April 2020 and March 2021. The prescribed drugs of participants were directly checked by pharmacists in the outpatient department preoperatively and 6-month and 1-year postoperatively. The baseline characteristics were collected beside the patient-based outcomes including Roland-Morris Disability Questionnaire, Zurich Claudication Questionnaire, and Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ). The cutoff number of drugs for polypharmacy was defined as 6. The prescription drugs were divided into 9 categories: drugs for neuropsychiatric, cardiovascular, respiratory, digestive, endocrine metabolic, and urinary renal diseases; blood products; pain relief medication; and others. RESULTS: A total of 102 cases were finally analyzed, with a follow-up rate of 78.0%. Of the participants, the preoperative polypharmacy prevalence was 66.7%. The number of drugs 6-month and 1-year postoperatively was significantly less than the preoperative one. The proportions of polypharmacy at 6 months and 1 year after surgery significantly decreased to 57.8% and 55.9%, respectively. When the prescribed drugs were divided into 9 categories, the number of drugs for pain relief and digestive diseases was significantly reduced after surgery. The multi-variable analysis revealed that a higher score in the psychological disorder of JOABPEQ was associated with 3 or more drugs decreased 1-year postoperatively (OR, 2.5; 95% CI: 1.0-6.1). CONCLUSION: Polypharmacy prevalence was high among elderly LSS patients indicated for lumbar spinal surgery. Additionally, our data showed that lumbar spinal surgery was effective in reducing polypharmacy among elderly LSS patients. Finally, the multi-variable analysis indicated that better psychological condition was associated with the reduction of prescribed drugs after lumbar spinal surgery.

Potential Involvement of Oxidative Stress in Ligamentum Flavum Hypertrophy.

Oxidative stress (OS) results in many disorders, of which degenerative musculoskeletal conditions are no exception. However, the interaction between OS and ligamentum flavum (LF) hypertrophy in lumbar spinal canal stenosis is not clearly understood. The first research question was whether OS was involved in LF hypertrophy, and the second was whether the antioxidant N-acetylcysteine (NAC) was effective on LF hypertrophy. In total, 47 LF samples were collected from patients with lumbar spinal disorders. The cross-sectional area of LF was measured on axial magnetic resonance imaging. Immunohistochemistry of 8-OHdG and TNF-α were conducted on human LF samples. A positive association was found between 8-OHdG or TNF-α expression and cross-sectional area of LF. Flow cytometry analysis showed that H2O2, buthionine sulfoximine, and TNF-α treatment significantly increased intracellular reactive oxygen species in primary LF cells. NAC inhibited the induction of LF hypertrophy markers by OS or TNF in a real-time reverse transcriptase polymerase chain reaction and enzyme-linked immunosorbent assay. Western blotting analysis indicated that p38, Erk, and p65 phosphorylation were involved in intracellular OS signaling in LF cells. In conclusion, our results indicated that OS could be a therapeutic target for LF hypertrophy. Although this study included no in vivo studies to examine the longitudinal efficacy of NAC on LF hypertrophy, NAC may have potential as a therapeutic agent against lumbar spinal canal stenosis.

Repeated Recurrence of Ligamentum Flavum Ossification After Posterior Spinal Surgery: A Case Report and Literature Review.

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.

Clinical and laboratory characteristics of complex febrile seizures in the acute phase: a case-series study in Japan.

BACKGROUND: Patients with complex febrile seizures (CFS) often display abnormal laboratory results, unexpectedly prolonged seizures, and/or altered consciousness after admission. However, no standardized values have been established for the clinical and laboratory characteristics of CFS in the acute phase, making the management of CFS challenging. This study aimed to determine the clinical and laboratory characteristics of children with CFS during the acute phase. In particular, the duration of impaired consciousness and the detailed distribution of blood test values were focused. METHODS: We retrospectively reviewed medical records of a consecutive pediatric cohort aged 6-60 months who were diagnosed with CFS and admitted to Kobe Children's Hospital between October 2002 and March 2017. During the study period, 486 seizure episodes with confirmed CFS were initially reviewed, with 317 seizure episodes included in the analysis. Detailed clinical and laboratory characteristics were summarized. RESULTS: Among 317 seizure episodes (296 children with CFS), 302 required two or fewer anticonvulsants to be terminated. In 296 episodes showing convulsive seizures, median seizure duration was 30.5 min. The median time from onset to consciousness recovery was 175 min. Impaired consciousness lasting > 6, 8, and 12 h was observed in 13.9%, 7.6%, and 1.9% patients with CFS, respectively. Additionally, the distribution of aspartate aminotransferase, lactate dehydrogenase, creatinine, and glucose were clarified with 3, 10, 50, 90, and 97 percentile values. CONCLUSION: This study detailed the clinical and laboratory findings of acute-phase CFS using the data of the largest 15-year consecutive cohort of children with CFS. These results provide important information for appropriate acute management of CFS.

Autologous Platelet-Rich Plasma Administration on the Intervertebral Disc in Low Back Pain Patients with Modic Type 1 Change: Report of Two Cases.

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.