Spine Surgery and Related Research最新文献

Introduction: For older adults, dysphagia is a serious problem that can occur after spinal cord injury (SCI), but its risk factors are unclear. This study aimed to identify risk factors for dysphagia in elderly patients (≥65 years) with cervical SCI.

Methods: This multicenter study included 707 patients with cervical SCI (mean age 75.3 years). Univariate and multivariate analyses were conducted for patient characteristics and geriatric nutritional risk index (GNRI).

Results: Dysphagia occurred in 69 patients (9.8%). The significant factors were as follows: male sex (odds ratio [OR] 3.43), GNRI <92 (1.83), dementia (2.94), fracture (3.40), complete paralysis (3.61), anterior surgery (3.74), and tracheostomy (17.06). Age was not identified as a risk factor.

Conclusions: Low GNRI before injury was one of the independent risk factors for dysphagia after geriatric cervical SCI. GNRI represents the comprehensive nutritional status of the elderly and reflects feeding function and its recovery capacity.

Introduction: Ligamentum flavum (LF) hypertrophy is the main etiological factor in the development of lumbar spinal stenosis (LSS); however, its molecular pathology remains unclear. Histologically, LF hypertrophy is characterized by a reduction in elastic fibers and an increase in collagen fibers. We previously performed miRNA transcriptomic analysis on excised LF from elderly patients with LSS and identified the insulin receptor signaling along with TGFβ-mediated signaling as pathways involved in ligament hypertrophy. Therefore, this study aimed to investigate the involvement of endogenous insulin as a risk factor for LF hypertrophy in patients with LSS.

Methods: A total of 1,119 patients aged ≥65 years (average: 76.1±5.9 years) treated for LSS including surgery and conservative treatment were analyzed. The flavum canal ratio (FCR) was calculated in the MRI cross-sectional image, and an FCR of 0.4275 or greater was defined as ligamentous stenosis according to Sakai's criteria. Homeostatic model assessment for insulin resistance (HOMA-IR) was calculated and values ≥2.5 were indicative of insulin resistance in Japanese people.

Results: Fifty-one percent of patients with LSS exhibited LF hypertrophy, correlating with higher age, proportion of males and diabetic patients, BMI, HOMA-IR, and creatinine. Among LSS patients, 43.0% had insulin resistance, with 47.1% exhibiting LF hypertrophy and 38.6% without LF hypertrophy, with a significant difference (p<0.01). LSS patients with high insulin resistance also demonstrated significantly higher FCR (p<0.05) and a higher percentage of LF hypertrophy (p<0.01). Conditional logistic regression analysis, adjusting for age, identified HOMA-IR as a significant factor.

Conclusions: The study establishes an association between LF hypertrophy and insulin resistance. Considering LF hypertrophy as an inflammation-triggered degeneration of elastic fibers, age-related changes in LF may underlie the basis of inflammatory aging.

Introduction: Few studies have assessed the minimum clinically important difference (MCID) of each Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) domain. This study assessed MCIDs of JOABPEQ in patients with lumbar spine disease by generation.

Methods: We evaluated the JOABPEQ score of 805 consecutive patients with lumbar spine disease undergoing posterior surgery preoperatively and 1 year postoperatively. MCIDs of each JOABPEQ domain were determined using anchor- and distribution-based methods according to age. A question based on the concept of a health transition item was used as the anchor for the MCID decision.

Results: Overall, MCIDs of the JOABPEQ were 28.6 and 27.3 points for pain-related disorder and gait disturbance, respectively. The MCID for the lumbar spine dysfunction domain did not reach 0.6 over the area under the curve. Regarding the differences among generations, MCIDs of pain-related disorder and gait disturbance domains differed slightly between the elderly and middle-aged. The psychological disorder domain did not reflect clinically meaningful changes in the elderly. MCIDs of the social life disturbance domain decreased with age.

Conclusions: Focusing on achieving the ideal responsiveness of patient-reported outcomes across generations, MCIDs of the pain-related disorder and gait disturbance domains may be valuable for patients, regardless of age, when adopting the JOABPEQ for patients with lumbar spine disease undergoing surgery. This study only evaluated cases that underwent posterior lumbar surgery. Future research will necessitate conducting surveys concerning the outcomes of various treatments for lumbar spine disease.

Introduction: Full endoscopic spine surgery continues to spread worldwide but has a long learning curve. Conventional endoscopy training uses live pigs or human cadavers, which has disadvantages such as high costs and limited availability. Therefore, this study aimed to develop and evaluate three-dimensional (3D)-printed models for endoscopy training.

Methods: Models for 3D printing were generated using raw imaging data from 1.0-mm slices of computed tomography scans, and each part was printed using a different colored material. The combined model was used for training as part of the full endoscopy training kit.

Results: This approach offers several advantages. First, it enables the creation of accurate disease models, such as lumbar disc herniation and other abnormalities, which are useful for both surgical training and preoperative simulations. Second, it is useful for learning surgical orientation. During surgical training, the surgical field can be viewed directly through an endoscope or with the naked eye. By using various colors, it becomes easier to recognize the orientation. Third, the amount of drilling resection can be easily confirmed, facilitating feedback. Finally, training for various surgical techniques is possible, including endoscopic holding techniques and using the endoscope's outer sheath to retract nerves. However, this approach also has some disadvantages, such as the lack of bleeding, inability to reproduce tissue hardness, and difficulty in faithfully recreating soft tissue, such as connective tissue, blood vessels, and fat. Therefore, it is difficult to reproduce the hardness of the calcified disc or disc herniation with apophyseal ring fracture. Moreover, 3D-printed models are not suitable for surgical training using the interlaminal approach because it is difficult to perform separation between the ligamentum flavum and dural matter or between the dural matter and intervertebral disc.

Conclusions: 3D-printed models are a useful complement to live pigs and human cadavers in surgical training and can reduce the time required to acquire endoscopic skills.

Introduction: Percutaneous vertebral augmentation techniques, such as balloon kyphoplasty (BKP) and vertebral body stenting (VBS), are commonly used for surgical intervention in osteoporotic vertebral fractures (OVFs). However, markedly unstable OVF cases require additional fixation procedures, prompting the exploration of combined percutaneous vertebral augmentation and posterior fixation. A novel surgical approach involving percutaneous vertebral augmentation with upward penetrating endplate screws (PES) and downward PES, complemented by a short fusion of one above one below, was developed. This study aimed to introduce and report the preliminary outcomes of this technique based on a retrospective analysis of 20 consecutive cases in the short and medium term.

Methods: Surgical indications are a vertebral wedge angle difference of 10° or more, vertebral pedicle fractures, posterior wall fractures, and diffuse low-signal changes exceeding 50% on T1-weighted magnetic resonance imaging. The procedure is reserved for highly unstable cases following a comprehensive health assessment. The surgical technique involves prone positioning, fluoroscopy-guided percutaneous vertebral augmentation, and the use of downward PES in the cranial vertebral body and upward PES for the caudal vertebral body by percutaneous technique. The fixation range is one above and one below.

Results: The case series of 20 patients, with an average follow-up period of 146.9 days, demonstrates a mean surgical time of 57 min and minimal complications. The advantages of the technique are as follows: ease of performance, minimal fixation range, and time efficiency. Risks, such as potential screw loosening and the need for prolonged follow-up, are acknowledged.

Discussion: The technique represents a promising surgical approach that balances the requirements of minimally invasive intervention and relatively robust initial fixation for elderly osteoporotic patients with unstable OVFs. While short- and medium-term results are favorable, long-term observations are needed to further assess its efficacy. This novel technique has a potential to be a valuable surgical option for unstable OVFs.

Background: Intradiscal condoliase injection for lumbar disc herniation (LDH) was developed in Japan in 2018. The treatment is intermediate between conservative therapy and surgery, and its frequency is increasing. Condoliase is limited to a single application over a lifetime, rendering it important to understand the indications and predictors of its effectiveness. This review aimed to summarize published studies and provide appropriate indications and limitations for appropriate patient selection based on existing findings.

Methods: While adhering to PRISMA guidelines, we searched the PubMed, Web of Science, and EMBASE databases to identify articles reporting the clinical outcomes of intradiscal condoliase injection for LDH. Data extraction focused on the effective rate, prognostic factors, and posttreatment imaging changes and was used in the meta-analysis.

Results: Nineteen studies met the inclusion criteria. Our meta-analysis revealed 78% total response, 11% posttreatment surgery, and 42% posttreatment Pfirrmann-classification-grade progression rates. Posttreatment intervertebral disc degeneration was potentially associated with an improved response rate and disc regeneration one year posttreatment, especially in young patients. The Regimen for patients aged <20 and >70 years should be carefully selected, including those with a disease duration of >1 year, recurrent LDH, small-sized LDH, vertebral instability, and inadequate duration (<3 months) of conservative therapy.

Conclusions: Although long-term outcomes and imaging changes must be evaluated owing to the heterogeneity of previous studies, intradiscal condoliase injection is a minimally invasive and cost-effective treatment option for patients with LDH. Treatment indications should be determined after carefully evaluating evidence from previous conservative and surgical treatments.

Lumbar interbody fusion (LIF) is a surgical procedure for treating lumbar spinal stenosis and deformities. It removes a spinal disc and insert a cage or bone graft to promote solid fusion. Extensive research on LIF has been supported by numerous animal studies, which are being developed to enhance fusion rates and reduce the complications associated with the procedure. In particular, the anterior approach is significant in LIF research and regenerative medicine studies concerning intervertebral discs, as it utilizes the disc and the entire vertebral body. Several animal models have been used for anterior LIF (ALIF), each with distinct characteristics. However, a comprehensive review of ALIF models in different animals is currently lacking. Medium-sized and large animals, such as dogs and sheep, have been employed as ALIF models because of their suitable spine size for surgery. Conversely, small animals, such as rats, are rarely employed as ALIF models because of anatomical challenges. However, recent advancements in surgical implants and techniques have gradually allowed rats in ALIF models. Ambitious studies utilizing small animal ALIF models will soon be conducted. This review aims to review the advantages and disadvantages of various animal models, commonly used approaches, and bone fusion rate, to provide valuable insights to researchers studying the spine.

Introduction: This study aimed to measure the intraocular pressure (IOP) of patients undergoing open surgery in the supine position (control group) and spine surgery in the prone position (spine group) to clarify IOP range and change by posture, determine the risk factors for increased IOP in the prone position, and reduce visual complications after surgery in the prone position.

Methods: A prospective cohort study was conducted in healthy adults (34-83 years of age) with an American Society of Anesthesiologists classification I/II. The spine group was examined for IOP, anterior chamber angle (ACA), and fundus findings the day prior to surgery. On the day of surgery, IOP measurements were taken at fixed time points: immediately after intubation; at 0.5, 1, and 2 h after intubation; at suture closure; and at the end of surgery in the control group. In the spine group, they were taken immediately after intubation; at 0.5, 1, and 2 h after prone position; at suture closure; and immediately and 5 min after returning to the supine position. The risk factors for increased IOP in the prone position were examined.

Results: The control group showed no significant changes in IOP within the normal range (<20 mmHg) during surgery. In the spine group, IOP was higher at each time point than immediately after intubation. IOP increased sharply above the normal range within 1 h after changing from the supine to the prone position and continued to gradually increase until suture closure. IOP decreased 5 min after the patient returned to the supine position. ACA, body mass index, blood loss, time in the prone position, and operative time were not risk factors for increased IOP in the prone position.

Conclusions: Patients were constantly exposed to above-normal IOP during prone spinal surgery. However, neither group reported visual impairment. No risk factors were identified for increased IOP in the prone position.

Introduction: This study investigates the outcomes of treating neglected unstable Hangman's fractures through a single-stage Anterior Cervical Discectomy and Fusion (ACDF) procedure with tricortical iliac crest bone grafts.

Methods: Five patients with neglected unstable Hangman's fractures, treated at our institution between March 2012 and March 2017, underwent C2-C3 ACDF. Functional outcomes were assessed using the Visual Analog Scale (VAS) score and Neck Disability Index (NDI), and neurological evaluation was done using the American Spinal Injury Association (ASIA) grading system. The radiological assessment included serial plain radiographs and a computed tomography scan at a 12-month follow-up.

Results: Postoperatively, C2-C3 angulation improved significantly, decreasing from 15° to 4.4°, and sagittal translation improved from 4.2 mm to 2 mm. The VAS score improved from 6.4 to 1.4 at 24 months postsurgery. Concurrently, NDI decreased from 70.4% to 14.8%. Fusion occurred in an average of 5.6 months. Neurologically, one patient improved from ASIA grade D to grade E, while the other four retained their grade E status.

Conclusions: A single-stage ACDF with autologous iliac crest bone grafts is an effective surgical option for neglected type II/IIA Hangman's fractures, yielding satisfactory functional and radiological outcomes. This technique significantly corrects anterior translation and angulation, even in neglected cases, with the aid of intraoperative skull traction and plate reduction.