Asian Spine Journal最新文献

Study design: A prospective cohort study.

Purpose: To determine the age-specific normative values of the prognostic nutritional index (PNI) among elderly residents in Japan and explore the relationship between malnutrition and spinal alignment.

Overview of literature: Nutritional status affects postoperative recovery, with malnourished patients often experiencing severe postoperative complications. PNI is a known nutritional indicator based on serological value; however, there is a dearth of age-specific normative values for PNI, with even less research on the impact of malnutrition on spinal alignment.

Methods: We included 237 participants from a 2-yearly resident health checkup conducted in Toei, Aichi, Japan. Participants underwent blood tests and whole-spine standing radiography, and were stratified based on age (60s, 70s, and 80s) and sex to determine age-specific normative PNI values. Additionally, participants were categorized into a lower PNI (PNI <50) or higher PNI (PNI ≥50) group to compare spinal alignment.

Results: The average PNI values for different age groups were: 60s: males (n=13): 50.7, females (n=31): 50.9; 70s: males (n=55): 50.3, females (n=57): 50.1; 80s: males (n=28): 49.1, females (n=53): 48.3. For females, the radiographic spinal alignment parameters were comparable between the lower and higher PNI groups; however, in males, significant differences were noted for pelvic tilt (20° vs. 16°, p=0.020), lumbar lordosis (35° vs. 44°, p<0.001), and pelvic incidence minus lumbar lordosis (10° vs. 4°, p=0.013).

Conclusions: Malnutrition in males negatively impacts their lumbar-pelvic alignment. While the normative PNI value decreases with age, the two variables show a very weak correlation.

Study design: Animal study.

Purpose: To investigate the effects of Lycium barbarum polysaccharide (LBP) on functional recovery following decompressive surgery in a rat model of cervical spondylotic myelopathy (CSM).

Overview of literature: Surgical decompression halts the progression of CSM, but may leave residual neurologic deficits. LBP, derived from wolfberry, has been shown to modulate macrophage polarization and exert neuroprotective effects in acute spinal cord injury. We hypothesized that LBP would enhance functional recovery after surgical decompression in a rat model of CSM.

Methods: Female Sprague-Dawley rats with induced chronic cervical spinal cord compression were randomly assigned to the following groups: (1) LBP alone; (2) decompression alone; (3) decompression+LBP; (4) no treatment; and (5) sham surgery. Decompression was performed 4 weeks after compression. Outcomes were assessed using neurobehavioral tests, electrophysiology, and histological/immunohistochemical analyses.

Results: Baseline spinal cord injury severity was comparable across groups, as confirmed by electrophysiological studies. At 8 weeks postsurgery, rats in the decompression+LBP group showed significantly greater recovery of hindlimb function compared with rats in the decompression alone group. Improvements in somatosensory evoked potential and motor evoked potential latency and amplitude were also more pronounced in the decompression+LBP group. Histological analyses demonstrated reduced myelin vacuolation and increased myelin density with LBP treatment.

Conclusions: This study provides the first evidence that LBP derived from Chinese herbal medicine enhances neurological and functional recovery when combined with decompression in a rat model of CSM. These findings support further clinical investigation of LBP as an adjunctive therapy in patients with CSM.

Study design: Retrospective analysis.

Purpose: To evaluate preoperative bone mineral density (BMD), as quantified by computerized tomography (CT)-derived Hounsfield unit (HU) values, in patients who underwent lumbar fusion and to examine the link between BMD and failed back surgery syndrome (FBSS).

Overview of literature: FBSS is a serious complication affecting 10%-40% of patients undergoing lumbosacral spinal surgery. Given the detrimental impact of FBSS on the psychological and physiological wellbeing of patients, preoperative identification of those at risk for developing FBSS and the implementation of targeted interventions to minimize this complication are highly important.

Methods: Preoperatively, all 115 patients underwent BMD assessments using both CT-derived HUs and dual-energy X-ray absorptiometry and were administered multiple questionnaires, including the Pain Catastrophizing Scale (PCS), Beck Anxiety Inventory (BAI), and Beck Depression Index (BDI). Both pain intensity and pain-related disability were assessed before and after lumbar fusion surgery.

Results: Postoperatively, 14 patients (14/115, 12.2%) experienced FBSS. Multivariate logistic regression was used to examine all preoperative covariates with significant differences between the patients with and without FBSS. The numeric rating pain scale score at rest, BAI score, PCS score, and HU value were found to be independently associated with FBSS (p<0.05).

Conclusions: This study revealed that preoperative BMD, as quantified by CT-derived HU values, may be associated with FBSS. Preoperative assessments of CT-derived HU values might provide additional details for identifying patients susceptible to FBSS, which could help prevent this complication.

Study design: A cross-sectional study.

Purpose: This study aimed to investigate temporal patterns, seasonal variations, and geographic differences in the US public interest in lumbar decompression and fusion surgery.

Overview of literature: The number of lumbar decompression and fusion surgery procedures for various surgical indications has significantly increased in the United States over the past few decades. As the prevalence of these procedures increases, patients are increasingly seeking online information on these procedures.

Methods: This study analyzed US public interest in lumbar decompression and fusion surgery using Google Trends data from January 1, 2015 to December 31, 2024. The relative search volume (RSV) was used to measure public interest. Temporal trends were assessed using linear regression analysis, whereas seasonal and geographic variations were evaluated using analysis of variance and Tukey's post hoc tests. Statistical significance was set at p<0.05.

Results: Public interest in lumbar decompression and fusion surgery showed a statistically significant upward trend from 2015 to 2024 (p<0.05), with R2 ranging from 0.0141 to 0.6748 across search terms. Monthly analysis revealed that the average search volume was highest in October (78.8%) and lowest in December (68.7%). No significant differences were observed among seasons (p=0.102). Geographically, the highest mean RSV was in the Northeast (43.3%), followed by the West (19.5%), Midwest (12.6%), South (11.1%), and Southwest (10.2%), with significant differences among these regions (p<0.001).

Conclusions: Public interest in lumbar decompression and fusion surgery has shown a consistent and statistically significant upward trend over the past decade. Although seasonal variation was not significant, notable geographic differences in search volume were observed, with the northeast showing the highest level of interest. These findings highlighted regional disparities in public engagement and may serve as a basis for future healthcare resource planning and patient education strategies.

Screw loosening (SL) is a common complication following lumbar interbody fusion (LIF), particularly for degenerative lumbar disease. This study investigated the risk factors for SL following LIF for degenerative lumbar disease and examined the clinical relevance of SL. A PROSPERO-registered systematic search was conducted in the ScienceDirect, PubMed, Google Scholar, Epistemonikos, and Cochrane databases to identify longitudinal studies up to October 2024. Degenerative lumbar diseases included stenosis, spondylolisthesis, and disc herniation. Assessed risk factors were Cobb angle, lumbar lordosis (LL) angle, screw length, fixation to the sacrum, fused levels, and Hounsfield units (HU). Twenty-two studies involving 3,689 participants (56%±5% female; mean age, 61.95±9.55 years) and 17,722 lumbar screws were analyzed. Overall, 10%±2% of screws exhibited loosening in 29%±5% of patients, with 5%±2% undergoing revision surgery. Patients with SL (SL group) and those without SL (non-SL group) had similar sex distribution, body mass index, and comorbidities. The SL group had higher Visual Analog Scale scores for back pain (mean difference [MD], 0.75; 95% confidence interval [CI], 0.42-1.07; p<0.001) and Oswestry Disability Index scores (MD, 3.34; 95% CI, 0.49-6.20; p=0.02), indicating the clinical relevance of SL. The SL group exhibited significantly higher Cobb angle (MD, 2.42; 95% CI, 0.36-4.49; p=0.02), lower LL angle (MD, -3.67; 95% CI, -6.33 to -1.01; p=0.01), and shorter screw length (MD, -1.62; 95% CI, -2.78 to -0.45; p=0.01). Fixation to the sacrum, increased fused levels, and decreased HU were significant risk factors. The area under the curve for HU was 0.80 (0.77-0.84), with a sensitivity of 0.74 (0.67-0.81) and specificity of 0.76 (0.66-0.84), underscoring notable prognostic value. Patients with SL exhibited higher Cobb angles, lower LL angles, and shorter screws. Fixation to sacrum, increased fused levels, and decreased HU were significant risk factors for SL (PROSPERO ID: CRD42024563780).

Study design: Retrospective cohort study.

Purpose: To evaluate whether untreated foraminal stenosis (FS) at levels not included in anterior cervical discectomy and fusion (ACDF) impacts postoperative outcomes in patients with cervical radiculopathy and assess if residual FS increases the risk of adjacent segment disease (ASD).

Overview of literature: Level selection for ACDF for cervical radiculopathy is complex, considering variable patient anatomy and symptoms. It is unclear whether treating only potentially symptomatic levels could provide equivalent results to managing all pathologic levels.

Methods: This was a retrospective cohort study of 188 patients undergoing ACDF for degenerative cervical radiculopathy between 2014 and 2020. Patients were divided into two groups: those with all symptomatic levels decompressed (No-FS group, n=162) and those with untreated FS at levels not targeted in surgery (FS group, n=26). Postoperative outcomes, including neck pain, arm pain, and Neck Disability Index (NDI), were evaluated at 3 months and 2 years. Radiographic parameters and ASD incidence were also compared between groups.

Results: Both groups showed significant improvement in neck pain, arm pain, and NDI postoperatively, with no significant intergroup differences at 3 months and 2 years. C2-C7 lordosis and sagittal vertical axis showed similar improvement in both groups postoperatively. Rates of ASD and revision surgery did not differ significantly between No-FS and FS groups (5.6% vs. 7.7%, respectively; p=0.652). Logistic regression revealed no significant predictors of NDI improvement >50% among preoperative demographic or radiographic factors.

Conclusions: Untreated FS at levels outside the surgical target area did not adversely affect ACDF outcomes or increase ASD risk over a 2-year follow-up. These findings suggest that ACDF can be safely limited to levels directly associated with patient symptoms without compromising clinical outcomes, potentially reducing the surgical extent and associated risks.

Study design: Cadaveric experimental study.

Purpose: To evaluate the feasibility and accuracy of pedicle screw placement using a custom-developed augmented reality-assisted pedicle screw fixation (ARPSF) system in a porcine spine model.

Overview of literature: Conventional pedicle screw placement techniques face limitations including potential inaccuracy, radiation exposure, and workflow disruption. Augmented reality technology can overlay virtual surgical planning directly onto the operative field while maintaining the surgeon's focus on the patient.

Methods: Five porcine cadaveric lumbar spines were used in this study. A custom-developed head-mounted display system with optical tracking projected three-dimensional reconstructed spine models and planned screw trajectories into the surgeon's field of view. A single experienced spine surgeon placed 50 pedicle screws (4.5 mm diameter). Registration was performed using a point-pair matching technique with fifteen anatomical landmarks. Accuracy was assessed via postoperative computed tomography scan, measuring entry point deviation, trajectory deviation, and angular difference, and evaluated using the Gertzbein-Robbins classification.

Results: Of the 50 pedicle screws placed, 47 (94%) achieved grade A accuracy with complete containment within the pedicle. The remaining three screws (6%) were classified as grade B, with minor breaches less than 2 mm. No unsafe placements (grades C-E) occurred. The mean entry point deviation was 0.55 mm (standard deviation [SD]=0.33 mm), and the mean deviation at the screw tip was 0.71 mm (SD=0.32 mm). The mean axial angular deviation was 2.04° (SD=0.58°). The average placement time was 2.2 minutes per screw.

Conclusions: The custom-developed ARPSF system demonstrated high accuracy for pedicle screw placement in a porcine model, achieving submillimeter precision and minimal angular deviation. This experimental study shows the potential of augmented reality technology to enhance spine instrumentation precision.

Despite the favorable postoperative prognosis of C5 palsy (C5P), a certain proportion of these patients have less satisfactory outcomes. The current systematic review and meta-analysis thus aimed to comprehensively evaluate existing literature and identify the onset, recovery patterns, and outcomes of C5P following diverse surgical approaches. Five different databases (Google Scholar, Embase, PubMed, Web of Science, and Cochrane Library) were thoroughly searched for relevant literature on October 15, 2024. Studies reporting on incidences of C5P following surgery for degenerative cervical conditions with recovery data published until 2024 were scrutinized. Narrative or systematic reviews, opinions, letters to the editor, and manuscripts published in non-English languages were excluded. A total of 30 articles involving 8,116 patients who underwent undergoing surgery for degenerative cervical myelopathy with 748 reported C5P cases were included for analysis. The overall time to palsy reported in the included studies was 3 days (95% confidence interval [CI], 2.56-3.60). Palsy occurred earliest with anterior cervical decompression and fusion (ACDF) at 2 days (95% CI, 0.35-4.54), followed by laminoplasty (LP) at 3.2 days (95% CI, 2.02-4.34) and posterior cervical decompression and fusion (PCDF) at 3.6 days (95% CI, 2.81-4.37). Patients with palsy showed improved recovery with time. At the 1-year follow-up, the reported recovery rates were 100%, 52.9%, and 50% for ACDF, LP, and PCDF, respectively. C5P demonstrated a delayed presentation, with mean onset of 3 days after surgery, which can range from 2 days for ACDF to 3.6 days for PDCF. Recovery improved progressively with time and varied for different surgical procedures, with ACDF showing the best recovery and PDCF for cervical myelopathy showing the poorest recovery.