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).

Polypharmacy of Older Surgical Patients With Extremity Fractures.

Introduction: Fractures are often caused by falls in older people. Among various causes of falls, polypharmacy is known to be a risk of falls. Furthermore, potentially inappropriate medicines (PIMs), which interact with polypharmacy, include the drugs involved in falls. Here, we primarily aimed to investigate the prescribed drugs in older surgical patients with extremity fractures to determine the frequency of polypharmacy and identify PIMs. The second aim was to clarify the characterization of prescribed drugs of older patients with hip fracture. Materials and Methods: We retrospectively collected the following clinical data of consecutive patients aged ≥65 years who underwent surgery for extremity fractures at our hospital between April 2019 and March 2021. A total of 19 categories were considered as PIMs. The Poisson regression models were used to examine the association between the number of prescribed drugs and hip fracture prevalence. Results: A total of 590 patients were reviewed. Our data showed that 55% of older patients with extremity fractures took ≥6 prescription drugs. The frequency of prescription of hypnotics, antithrombotic drugs, diuretics, and non-steroidal anti-inflammatory drugs was comparatively high among the 19 categories of PIMs. Multivariable analysis revealed that polypharmacy was significantly associated with hip fractures. Among PIMs, antithrombotic drugs and diuretics were significantly associated with the prevalence of hip fractures. Finally, we found a significant positive association between the prevalence of hip fracture and the number of drug categories of PIMs among older patients with extremity fractures. Conclusions: The present study clarified the characterization of the prescribed drugs in older surgical patients with extremity fractures. Special attention should be paid to hip fractures of older patients with polypharmacy or prescribed with many drugs categories of PIMs, particularly antithrombotic drugs and diuretics.

Fluoride-treated rare earth-free magnesium alloy ZK30: An inert and bioresorbable material for bone fracture treatment devices.

Bone fractures represent a common health problem, particularly in an increasingly aging population. Bioresorbable magnesium (Mg) alloy-based implants offer promising alternatives to traditional metallic implants for the treatment of bone fractures because they eliminate the need for implant removal after healing. The Mg-Y-rare-earth (RE)-Zr alloy WE43, designed for orthopedic implants, has received European Conformity mark approval. However, currently, WE43 is not clinically used in certain countries possibly because of concerns related to RE metals. In this study, we investigated the use of a RE-free alloy, namely, Mg-Zn-Zr alloy (ZK30), as an implant for bone fractures. Hydrofluoric acid (HF) treatment was performed to improve the corrosion resistance of ZK30. HF-treated ZK30 (HF-ZK30) exhibited lower corrosion rate and higher biocompatibility than those of WE43 in in vitro experiments. After implanting a rod of HF-ZK30 into the fractured femoral bones of mice, HF-ZK30 held the bones and healed the fracture without deformation. Treatment results of HF-ZK30 were comparable to those of WE43, indicating the potential of HF-ZK30 as a bioresorbable and safe implant for bone repair.

Imaging Characteristics of Non-Rheumatoid Arthritis Patients With Retro-Odontoid Pseudotumor: A Multicenter Case-Control Study.

STUDY DESIGN: Multicenter case-control study. OBJECTIVE: To identify imaging characteristics of the cervical spine in patients with retro-odontoid pseudotumor (ROP) without rheumatoid arthritis (RA) and determine the pathogenesis of ROP. SUMMARY OF BACKGROUND DATA: ROP results from proliferative changes in the soft tissue of the atlantoaxial junction surrounding the region of the transverse ligament, and is commonly seen in RA patients. However, the pathogenesis of ROP caused by mechanical instability of the upper cervical spine in patients without RA is yet to be explained. METHODS: We collected imaging data (preoperative radiographs, magnetic resonance imaging [MRI], and computed tomography [CT]) of patients who underwent surgery between April 2011 and March 2022 at the three university hospitals for ROP (cases) and cervical spondylotic myelopathy (as age, sex, and institution matched controls). The two groups were compared for different parameters on cervical dynamic radiographs, MRI, and CT. RESULTS: The ROP group consisted of 42 patients, and the control group comprised 168 patients. C2-C7 range of motion was significantly smaller in the ROP group (25.8 ± 2.6°) compared to the control group (33.0 ± 1.0°). C2-C7 sagittal vertical axis was significantly larger in the ROP group than the control group (39.3 ± 3.6 mm versus 32.2 ± 1.3 mm). MRI and CT assessment showed progressive degeneration at all intervertebral levels in the ROP group. A significant positive correlation was observed between the thickness of the soft tissue posterior to the dental process and the atlantodental interval in the flexion position (r = 0.501). CONCLUSION: The development of ROP was associated with degeneration of facet joints and intervertebral discs in the middle and lower cervical spine. Our findings suggest that decreased mobility of the middle and lower cervical spine may cause instability in the upper cervical spine, leading to the formation of ROP.

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.

Determinants of Gait Parameters in Patients With Severe Hip Osteoarthritis.

OBJECTIVE: To investigate the characteristics and symptoms of patients with hip osteoarthritis that are associated with spatiotemporal gait parameters, including their variability and asymmetry. DESIGN: A retrospective, cross-sectional study. SETTING: University hospital. PARTICIPANTS: The study analyzed the gait analysis data of 155 patients (N=155) with hip osteoarthritis who were admitted to a university hospital for total hip replacement and were able to walk on a treadmill without a handrail. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The dependent variables were gait parameters during treadmill walking. These included gait speed, stride length, cadence, coefficient of variation of stride length and stride time, swing time symmetry index, and step symmetry index. Single and multiple regression analyses were conducted using independent variables of the characteristics and symptoms of the patients, including age, sex, height, pain, leg-length discrepancy, and muscle strength of the affected and normal sides measured with a hand-held dynamometer (iliopsoas, gluteus medius, and quadriceps). RESULTS: In the analysis, gait speed and stride were the dependent variables, whereas age, height, and muscle strength on the affected side were the significant independent variables (P<.05). Additionally, pain demonstrated a marginal association with gait speed (P=.053). Only the leg-length discrepancy correlated with cadence. When the coefficient of variation of the stride length was the dependent variable, age and muscle strength on the affected side were significant. For the swing time symmetry index, only the muscle strength on the affected side was significant. Furthermore, the step symmetry index only correlated with leg-length discrepancy. The muscle strength on the affected side was the only significant independent variable for the coefficient of variation of the stride time. CONCLUSIONS: The results revealed that each of the frequent clinical symptoms of hip osteoarthritis, such as pain, muscle weakness, and leg-length discrepancy, can explain different aspects of gait performance.

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.

Spatial heterogeneity of bone marrow endothelial cells unveils a distinct subtype in the epiphysis.

Bone marrow endothelial cells (BMECs) play a key role in bone formation and haematopoiesis. Although recent studies uncovered the cellular taxonomy of stromal compartments in the bone marrow (BM), the complexity of BMECs is not fully characterized. In the present study, using single-cell RNA sequencing, we defined a spatial heterogeneity of BMECs and identified a capillary subtype, termed type S (secondary ossification) endothelial cells (ECs), exclusively existing in the epiphysis. Type S ECs possessed unique phenotypic characteristics in terms of structure, plasticity and gene expression profiles. Genetic experiments showed that type S ECs atypically contributed to the acquisition of bone strength by secreting type I collagen, the most abundant bone matrix component. Moreover, these cells formed a distinct reservoir for haematopoietic stem cells. These findings provide the landscape for the cellular architecture in the BM vasculature and underscore the importance of epiphyseal ECs during bone and haematopoietic development.

Chromosome-level genome assemblies of Cutaneotrichosporon spp. (Trichosporonales, Basidiomycota) reveal imbalanced evolution between nucleotide sequences and chromosome synteny.

BACKGROUND: Since DNA information was first used in taxonomy, barcode sequences such as the internal transcribed spacer (ITS) region have greatly aided fungal identification; however, a barcode sequence alone is often insufficient. Thus, multi-gene- or whole-genome-based methods were developed. We previously isolated Basidiomycota yeasts classified in the Trichosporonales. Some strains were described as Cutaneotrichosporon cavernicola and C. spelunceum, whereas strain HIS471 remained unidentified. We analysed the genomes of these strains to elucidate their taxonomic relationship and genetic diversity. RESULTS: The long-read-based assembly resulted in chromosome-level draft genomes consisting of seven chromosomes and one mitochondrial genome. The genome of strain HIS471 has more than ten chromosome inversions or translocations compared to the type strain of C. cavernicola despite sharing identical ITS barcode sequences and displaying an average nucleotide identity (ANI) above 93%. Also, the chromosome synteny between C. cavernicola and the related species, C. spelunceum, showed significant rearrangements, whereas the ITS sequence identity exceeds 98.6% and the ANI is approximately 82%. Our results indicate that the relative evolutionary rates of barcode sequences, whole-genome nucleotide sequences, and chromosome synteny in Cutaneotrichosporon significantly differ from those in the model yeast Saccharomyces. CONCLUSIONS: Our results revealed that the relative evolutionary rates of nucleotide sequences and chromosome synteny are different among fungal clades, likely because different clades have diverse mutation/repair rates and distinct selection pressures on their genomic sequences and syntenic structures. Because diverse syntenic structures can be a barrier to meiotic recombination and may lead to speciation, the non-linear relationships between nucleotide and synteny diversification indicate that sequence-level distances at the barcode or whole-genome level are not sufficient for delineating species boundaries.

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.

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.

Evidence of causality of low body mass index on risk of adolescent idiopathic scoliosis: a Mendelian randomization study.

Introduction: Adolescent idiopathic scoliosis (AIS) is a disorder with a three-dimensional spinal deformity and is a common disease affecting 1-5% of adolescents. AIS is also known as a complex disease involved in environmental and genetic factors. A relation between AIS and body mass index (BMI) has been epidemiologically and genetically suggested. However, the causal relationship between AIS and BMI remains to be elucidated. Material and methods: Mendelian randomization (MR) analysis was performed using summary statistics from genome-wide association studies (GWASs) of AIS (Japanese cohort, 5,327 cases, 73,884 controls; US cohort: 1,468 cases, 20,158 controls) and BMI (Biobank Japan: 173430 individual; meta-analysis of genetic investigation of anthropometric traits and UK Biobank: 806334 individuals; European Children cohort: 39620 individuals; Population Architecture using Genomics and Epidemiology: 49335 individuals). In MR analyses evaluating the effect of BMI on AIS, the association between BMI and AIS summary statistics was evaluated using the inverse-variance weighted (IVW) method, weighted median method, and Egger regression (MR-Egger) methods in Japanese. Results: Significant causality of genetically decreased BMI on risk of AIS was estimated: IVW method (Estimate (beta) [SE] = -0.56 [0.16], p = 1.8 × 10-3), weighted median method (beta = -0.56 [0.18], p = 8.5 × 10-3) and MR-Egger method (beta = -1.50 [0.43], p = 4.7 × 10-3), respectively. Consistent results were also observed when using the US AIS summary statistic in three MR methods; however, no significant causality was observed when evaluating the effect of AIS on BMI. Conclusions: Our Mendelian randomization analysis using large studies of AIS and GWAS for BMI summary statistics revealed that genetic variants contributing to low BMI have a causal effect on the onset of AIS. This result was consistent with those of epidemiological studies and would contribute to the early detection of AIS.

Nationwide Survey of the Surgical Complications Associated with Lateral Lumbar Interbody Fusion in 2015-2020.

Introduction: Lateral lumbar interbody fusion (LLIF) has been introduced in Japan in 2013. Despite the effectiveness of this procedure, several considerable complications have been reported. This study reported the results of a nationwide survey performed by the Japanese Society for Spine Surgery and Related Research (JSSR) on the complications associated with LLIF performed in Japan. Methods: JSSR members conducted a web-based survey following LLIF between 2015 and 2020. Any complications meeting the following criteria were included: (1) major vessel, (2) urinary tract, (3) renal, (4) visceral organ, (5) lung, (6) vertebral, (7) nerve, and (8) anterior longitudinal ligament injury; (9) weakness of psoas; (10) motor and (11) sensory deficit; (12) surgical site infection; and (13) other complications. The complications were analyzed in all LLIF patients, and the differences in incidence and type of complications between the transpsoas (TP) and prepsoas (PP) approaches were compared. Results: Among the 13,245 LLIF patients (TP 6,198 patients [47%] and PP 7,047 patients [53%]), 389 complications occurred in 366 (2.76%) patients. The most common complication was sensory deficit (0.5%), followed by motor deficit (0.43%) and weakness of psoas muscle (0.22%). Among the patient cohort, 100 patients (0.74%) required revision surgery during the survey period. Almost half of the complications developed in patients with spinal deformity (183 patients [47.0%]). Four patients (0.03%) died from complications. Statistically more frequent complications occurred in the TP approach than in the PP approach (TP vs. PP, 220 patients [3.55%] vs. 169 patients [2.40%]; p<0.001). Conclusions: The overall complication rate was 2.76%, and 0.74% of the patients required revision surgery because of complications. Four patients died from complications. LLIF may be beneficial for degenerative lumbar conditions with acceptable complications; however, the indication for spinal deformity should be carefully determined by the experience of the surgeon and the extent of the deformity.

First clinical experience with posterior lumbar interbody fusion using a thermal-sprayed silver-containing hydroxyapatite-coated cage.

BACKGROUND: To investigate the possibility of silver (Ag)-induced adverse events and the degree of bone fusion in posterior lumbar interbody fusion surgery using an Ag-containing hydroxyapatite (HA) lumbar interbody cage. METHODS: An Ag-HA cage consisting of highly osteoconductive HA interfused with Ag was developed, and we applied it clinically at three university-affiliated hospitals from April 2020 to December 2020. During the 12-month postoperative observation period, Ag-related adverse events, neuropathy, and postoperative complications were investigated as indicators of safety, while clinical improvement and the fusion status were investigated as indicators of efficacy. Clinical improvement was defined as improvement beyond the minimum clinically important difference (MCID) in the numerical rating scale (NRS; 1.6) for low back and lower limb pain and the Oswestry Disability Index (ODI; 12.8). RESULTS: We performed lumbar interbody fusion using an Ag-HA cage for 48 patients (female, n = 25; mean age, 67.5 years). The mean preoperative NRS was 6.4 (standard deviation, 1.9), while the mean preoperative ODI was 44 [12]. No adverse effects (i.e., argyria) were identified during the 12-month observation period. Surgical site infection occurred in one case, although the implant was preserved via immediate debridement. In total, 39 (81%) participants showed clinical improvement beyond MCID for both NRS and ODI. Bone fusion was achieved at 45 levels (88%) at 6 months and 48 levels (91%) at 12 months postoperatively. CONCLUSIONS: The results of this study suggest that Ag-HA cages can be safely used in spinal fusion procedures and have the potential to prevent postoperative infections, prevent deterioration of the quality of life, and result in favorable outcomes. Larger-scale and longer-term follow-up studies will be required to corroborate these conclusions. Trial registration UMIN 000039964 (date: April 01, 2020).