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: A halo vest is an immobilization device widely used to stabilize the cervical spine. Pain and infection at the skull pin insertion site are common complications, but skull perforation is rare, and most published studies are case reports. This study aimed to identify risk factors for skull perforation by comparing patients who did and did not develop perforation.

Methods: Overall thickness and the thicknesses of the internal and external laminae of the skull at the skull pin insertion sites were measured on cranial computed tomography scans of 66 patients fitted with a halo vest. The results were compared between patients who did and did not develop perforation.

Results: Four patients developed perforations. All patients with perforation were older women, and their external and internal laminae were significantly thinner than those of patients who did not develop perforation.

Conclusions: The reported causes of skull pin perforation include infection around the pin, osteoporosis, and an enlarged frontal sinus. However, most patients with perforation in the present study were older women, and the cause was the thinning of the external and external laminae.

Introduction: Human pose estimation, a computer vision technique that identifies body parts and constructs human body representations from images and videos, has recently demonstrated high performance through deep learning. However, its potential application in clinical photography remains underexplored. This study aimed to establish photographic parameters for patients with adolescent idiopathic scoliosis (AIS) using pose estimation and to determine correlations between these photographic parameters and corresponding radiographic measures.

Methods: We conducted a study involving 42 patients with AIS who had undergone spinal correction surgery and conservative treatment. Preoperative photographs were captured using an iPhone 13 Pro mounted on a tripod positioned at the head of an X-ray tube. From the outputs of pose estimation, we derived five photographic parameters and subsequently conducted a statistical analysis to assess their correlations with relevant conventional radiographic parameters.

Results: In the sagittal plane, we identified significant correlations between photographic and radiographic parameters measuring trunk tilt angles. In the coronal plane, significant correlations were found between photographic parameters measuring shoulder height and trunk tilt and corresponding radiographic measurements.

Conclusions: The results suggest that pose estimation, achievable with common mobile devices, offers potential for AIS screening, early detection, and continuous posture monitoring, effectively mitigating the need for X-ray radiation exposure. Level of Evidence: 3.

Introduction: Despite that lateral lumbar interbody fusion (LLIF) is a minimally invasive surgery, some patients complain of severe site pain immediately after the surgery. This study aimed to explore the extent of perioperative pain after LLIF, compare the degree of perioperative pain after LLIF with that after other surgical procedures, and evaluate the factors associated with severe pain in the early postoperative period.

Methods: In this study, 93 patients who underwent lumbar spine surgeries for lumbar degenerative diseases were analyzed. The patients were categorized into three groups based on the surgical procedure: Group L, LLIF with percutaneous pedicle screw (PPS); Group P, posterolateral fusion (PLF) or posterior lumbar interbody fusion (PLIF); and Group D, posterior decompression (fenestration). The extent of low back pain was evaluated using the visual analog scale (VAS) preoperatively and from postoperative days 1 to 14.

Results: The VAS score for postoperative pain decreased in a time-dependent manner in all three groups (P<0.01). Repeated measures analysis of variance (ANOVA) showed that the VAS in Group L was significantly higher than that in Group D (P<0.01). Time point analysis revealed that the VAS scores from postoperative days 1 to 9 in Group L were significantly higher than those in Group D (P<0.05). No significant difference was observed in the VAS scores of postoperative pain between Groups L and P on all postoperative days. The VAS score for early postoperative pain in Group L was significantly correlated with the change in disc height index (P<0.05, r=0.43) and tended to be associated with the grade of preoperative disc degeneration and the VAS score of preoperative low back pain (P=0.076-0.19).

Conclusions: This study is the first to evaluate the factors associated with pain during the early postoperative period of LLIF. Although LLIF is a minimally invasive surgery, severe pain may develop in patients with significant preoperative disc degeneration or following spinal correction surgery.

Introduction: Chemonucleolysis with condoliase is a minimally invasive treatment option for lumbar disk herniation (LDH). However, studies reporting the efficacy of condoliase in patients aged <20 years are scarce. Therefore, the present study aimed to evaluate the efficacy of condoliase therapy for LDH in the aforementioned population.

Methods: Condoliase administration was determined based on adequate informed consent. The study enrolled 138 patients (mean age, 41.3±15.4 years) with LDH who received condoliase injections with a follow-up period of 1 year. The patients were divided into Group Y (age, <20 years) and Group A (age, 20-70 years). The clinical outcomes were visual analog scale (VAS) scores for leg and back pain and Oswestry Disability Index (ODI) values. Changes in disk height and degeneration were evaluated. These data were obtained at baseline and at the 3-month and 1-year follow-ups. Condoliase therapy was considered to be effective if it improved the VAS score for leg pain by ≥50% at 1 year from baseline and prevented surgery.

Results: Groups Y and A consisted of 15 and 123 patients, respectively. Condoliase therapy was effective in 9 patients (60.0%) in Group Y and 96 patients (78.0%) in Group A. The rates of Pfirrmann grade deterioration and recovery were substantially higher in Group Y than in Group A (83.3% vs. 45.8% and 50.0% vs. 16.3%, respectively). While the disk height reduction in Group Y was greater at 3 months, it recovered to the same level as that in Group A at 1 year. In Group Y, patients who did not respond to the treatment exhibited a considerably higher preoperative ODI (P<0.05).

Conclusions: Chemonucleolysis with condoliase is considered to have limited efficacy in patients aged <20 years. Caution should be taken when managing cases showing lumbar instability or existing disability. While chemonucleolysis with condoliase is a less invasive treatment option for LDH, the administration should be decided upon with sufficient consent considering the potential limited efficacy and disk degeneration.

Introduction: Pedicle screws are commonly used in fixation to treat various spinal disorders. However, screw loosening is a prevalent complication, particularly in patients with osteoporosis. Various biomechanical studies have sought to address this issue, but the optimal depth and trajectory to increase the fixation strength of pedicle screws remain controversial. Therefore, a biomechanical study was conducted using finite element models.

Methods: Three-dimensional finite element models of the L3 vertebrae were developed from the preoperative computed tomography images of nine patients with osteoporosis and nine patients without who underwent spine surgery. Unicortical and bicortical pedicle screws were inserted into the center and into the anterior wall of the vertebrae, respectively, in different trajectories in the sagittal plane: straightforward, cephalad, and caudal. Subsequently, three different external loads were applied to each pedicle screw at the entry point: axial pullout, craniocaudal, and lateromedial loads. Nonlinear analysis was conducted to examine the fixation strength of the pedicle screws.

Results: Irrespective of osteoporosis, the bicortical pedicle screws had greater fixation strength than the unicortical pedicle screws in all trajectories and external loads. The fixation strength of the bicortical pedicle screws was not substantially different among the trajectories against any external loads in the nonosteoporotic vertebrae. However, the fixation strength of the bicortical pedicle screws against craniocaudal load in the cephalad trajectory was considerably greater than those in the caudal (P=0.016) and straightforward (P=0.023) trajectories in the osteoporotic vertebrae. However, this trend was not observed in pullout and lateromedial loads.

Conclusions: Our results indicate that bicortical pedicle screws should be used, regardless of whether the patient has osteoporosis or not. Furthermore, pedicle screws should be inserted in the cephalad trajectory in patients with osteoporosis.

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: This study aimed to investigate the relationship between childbirth and lower back pain and determine the health-related quality of life of female patients with lower back pain.

Methods: A total of 111 patients were divided into three groups: those who had given birth and developed lower back pain due to pregnancy, childbirth, or child-rearing movements (childbirth group, n=41), those who had given birth and developed lower back pain due to other causes (childbirth and other cause group, n=29), and those who were nulliparous (nulliparous group, n=41). A total of 22 physical therapists evaluated the patients during initial rehabilitation. Basic information and health-related quality of life were compared among the three groups using a one-way analysis of variance for the visual analog scale scores for lower back pain, summary scores (physical health [physical component summary] and mental health [mental component summary]), and subscales (physical functioning, role-physical, bodily pain, general health, vitality, social functioning, role-emotional, and mental health) of the Short Form-8 Health Survey. These values were also compared with the national standard values for health-related quality of life. The chi-square test of independence was used to compare distributions, and Fisher's exact probability test was used for cells with an expected value of <5.

Results: Most participants had physical component summary scores below the national standard values. The visual analog scale scores for lower back pain were significantly higher in the birth group than in the nonbirth group. The physical component summary, physical functioning, and general health scores were significantly lower in the birth group than in the nonbirth group. Moreover, bodily pain scores were significantly lower in the birth group than in the other groups.

Conclusions: For female patients with lower back pain due to pregnancy, childbirth, or childcare activities, physical conditions unique to postpartum women should be considered, and if necessary, instructions for activities of daily living should be provided.

Introduction: In high-grade spinal osteotomy involving large anterior column resection, restoration of the structural integrity of the posterior column at the osteotomy site can reduce postoperative instrumentation failure (IF). This study aimed to describe our technique of posterior strut bone grafting using an en bloc resected vertebral arch, which is useful for posterior column reconstruction after high-grade osteotomies during surgeries for spinal tumor and deformity in the lower lumbar spine.

Technical Note: Using a posterior approach, en bloc resection of the targeted vertebral arch was performed in accordance with the surgical technique for total en bloc spondylectomy (TES). The posterior elements in the upper and lower adjacent vertebrae were separated by a significant space after vertebral body resection followed by cage insertion in TES or anterior column osteotomy followed by correction in deformity surgery. To create a new posterior column, the en bloc resected vertebral arch was placed at 90° rotation to bridge the upper and lower vertebral arches. Using this technique, an abundant amount of bone chips made from the resected vertebral elements were placed over the en bloc resected posterior arch as an additional bone graft. The technique was used in three patients who underwent TES for spinal tumors and in one patient who underwent grade 4 osteotomy for adult spinal deformity in the lower lumbar spine. One year after surgery, computed tomography showed that the structural integrity of bony fusion was successfully achieved between the en bloc resected arch and the posterior elements of the adjacent vertebrae in all patients and showed no postoperative IFs.

Conclusions: This bone graft technique created new continuity of the posterior column after high-grade osteotomies in the lower lumbar spine. Bone fusion was achieved in the posterior elements to prevent IF after surgery.