Early Balloon Kyphoplasty Treatment for Osteoporotic Vertebral Fracture Reduces Adjacent Vertebral Fractures.

Background and Objectives: This study retrospectively examined whether the incidence rates of adjacent vertebral fractures (AVFs) can be reduced through balloon kyphoplasty (BKP) for osteoporotic vertebral fractures (OVFs) in the early stages, when there is little vertebral height variation. Materials and Methods: A total of 95 patients (22 males, 73 females, mean age: 80.7 years) who had undergone BKP were divided into two groups: the Early group (underwent BKP within 2 weeks after injury, n = 62), and the Non-early group (underwent BKP > 2 weeks after injury, n = 33). The following data were analyzed: patient characteristics; fracture level; the presence of old vertebral fractures, posterior wall injury, and intravertebral cleft; duration of surgery; duration of hospitalization; cement volume; the occurrence of AVF; the timing of AVF occurrence; Numerical Rating Scale (NRS) scores at the preoperative, postoperative, and final follow-up assessments; posterior vertebral kyphosis angle of the affected vertebra on plain lateral X-ray; vertebral wedge ratio; local kyphotic angle; and changes in posterior vertebral kyphosis angle, vertebral wedge ratio, and local kyphotic angle between preoperative and postoperative assessments. The patients were divided based on the occurrence or non-occurrence of AVF after BKP: the Non-AVF group, in which AVF did not occur, and the AVF group, in which AVF occurred. Results: The incidence of AVF was 15.8% (15/95 patients), with a notably lower incidence rate in the Early group at 6.5% (4/62 patients) compared to the Non-early group at 33.3% (11/33 patients). NRS scores significantly improved in both groups at the postoperative assessment and final follow-up. The changes in posterior vertebral kyphosis angle and vertebral wedge ratio were significantly lower in the Early group. In the Non-AVF group, the time from injury to surgery was significantly shorter. Conclusions: The Early group had a significantly lower incidence of AVF. The time from injury to surgery was a risk factor for AVF occurrence, suggesting that early BKP is recommended.

Elimination of Lumbar Plexus Injury by Changing the Entry Point and Traction Direction of the Psoas Major Muscle in Transpsoas Lateral Lumbar Spine Surgery.

Background and Objectives: The lateral approach is commonly used for anterior column reconstruction, indirect decompression, and fusion in patients with lumbar degenerative diseases and spinal deformities. However, intraoperative lumbar plexus injury may occur. This is a retrospective comparative study to investigate and compare neurological complications between the conventional lateral approach and a modified lateral approach at L4/5. Materials and Methods: Patients with a lumbar degenerative disease requiring single-level intervertebral fusion at L4/5 were included and categorized into group X and group A. Patients in group X underwent conventional extreme lateral interbody fusion, while those in group A underwent a modified surgical procedure that included splitting of the anterior third of the psoas muscle, which was dilated by the retractor on the anterior third of the intervertebral disc. The incidence of lumbar plexus injury, defined as a decrease of ≥1 grade on manual muscle testing of hip flexors and knee extensors and sensory impairment of the thigh for ≥3 weeks, on the approach side, was investigated. Results: Each group comprised 50 patients. No significant between-group differences in age, sex, body mass index, and approach side were observed. There was a significant between-group difference in intraoperative neuromonitoring stimulation value (13.1 ± 5.4 mA in group X vs. 18.5 ± 2.3 mA in group A, p < 0.001). The incidence of neurological complications was significantly higher in group X than in group A (10.0% vs. 0.0%, respectively, p < 0.05). Conclusions: In our modified procedure, the anterior third of the psoas muscle was entered and split, and the intervertebral disc could be reached without damaging the lumbar plexus. When performing lumbar surgery using the lateral approach, lumbar plexus injury can be avoided by following surgical indication criteria based on the location of the lumbar plexus with respect to the psoas muscle and changing the transpsoas approach to the intervertebral disc.

Three-dimensional morphological analysis of the thoracic pedicle and related radiographic factors in adolescent idiopathic scoliosis.

BACKGROUND: This study aimed to investigate the laterality of the pedicle morphology at the apical vertebra (AV) level and identify the radiographic factors associated with the laterality ratio of the pedicle morphology at the AV level in patients with adolescent idiopathic scoliosis (AIS). METHODS: Overall, 684 pedicles in 57 AIS patients aged 10-20 years, who underwent preoperative computed tomography (CT) and had Lenke type 1 or 2 with right convex main thoracic curves (MTC), were evaluated. Pedicle diameters of the MTC were assessed. We defined and compared the region containing two vertebrae adjacent to the AV (APEX±1) and the region containing two vertebrae adjacent to the neutral vertebra. We analyzed the pedicle diameter and laterality ratio of APEX±1 and performed multiple linear regression analysis to identify the radiographic factors associated with the laterality of the pedicle diameter. RESULTS: On the concave side of APEX±1, the pedicles of 15 patients (26.3%) did not accept a 4-mm-diameter pedicle screw (PS), even with 25% cortical bone width expansion. Laterality ratio differences in the pedicle diameters of the cortical bone width in APEX±1 were large in patients with more proximal AV level (p < 0.001) and smaller apical vertebral rotation (AVR) (p = 0.029). CONCLUSIONS: Preoperative planning to accurately select and insert the PS in AIS should be based on the anatomical limitations in APEX±1, AV level, and AVR degree. In APEX±1, the correlation between AVR and the laterality ratio of the pedicle diameter may be useful for pathoetiological interpretation of the AIS deformity.

Trans-Sacral Epiduroscopic Ho:YAG Laser Ablation of the Ligamentum Flavum in a Live Pig.

Introduction: For the aging population, surgery for lumbar spinal canal stenosis (LSCS) requires minimally invasive procedures. Recently, trans-sacral epiduroscopic laser decompression for lumbar disc herniation has been reported with good results. In this study, we devised a new method to perform trans-sacral epiduroscopic laser ablation of the ligamentum flavum (LF), known to be the major cause of LSCS. Using a live pig, this study aims to evaluate the efficacy, safety, and drawbacks of this procedure. Methods: Using an epiduroscope, we observed intra-spinal canal structures and then examined the feasibility and problems of a decompression procedure to ablate the LF using holmium:YAG (Ho:YAG) laser. The pig was observed for behavioral changes and neurological deficits after the procedure. Histological analysis was performed to evaluate the amount of tissue ablation and damage to surrounding tissues. Results: Although it was possible to partially ablate the LF using the Ho:YAG laser under epiduroscopy, it was difficult to maintain a clear field of view, and freely decompressing the target lesion has been a challenge. After the first two experiments, the pig neither showed abnormal behavior nor any signs of pain or paresis. However, in the third experiment, the pig died during the operation. On autopsy, no thermal or mechanical injury was noted around the ablated site, including the dura mater and nerve root. Histological analysis showed that the LF and lamina were deeply ablated as the laser power increased, and no damage was noted on surrounding tissues beyond a depth of 500 µm. Conclusions: Although Ho:YAG laser could ablate the ligamentum and bone tissues without causing damage to surrounding tissues, it was difficult to completely decompress the LF under epiduroscopy. This method is a potentially highly invasive procedure that requires caution in its clinical application and needs further improvement in terms of the instruments and techniques used.

Influence of surgical approach on final outcome in total hip arthroplasty for osteoarthritis in patients older than 80 years.

PURPOSE: We compared the outcome of total hip arthroplasty (THA) in this age group using direct anterior or posterior approach. METHODS: We performed a retrospective analysis following consecutive primary THA in patients over 80 years. RESULTS: The DAA group demonstrated significantly shorter length of stay, better functional improvement, no dislocation or revision while PA group required two revisions due to dislocation. CONCLUSIONS: The use of DAA for THA in the elderly was associated with shorter hospitalization and superior functional outcomes in the early post-operative period, and had a lower rate of dislocation without increasing risk of early revision.