Neurological Analysis Based on the Terminal End of the Spinal Cord and the Narrowest Level of Injured Spine in Thoracolumbar Spinal Injuries

This study aimed to clarify neurological differences among the epiconus, conus medullaris, and cauda equina syndromes. Eighty-seven patients who underwent surgery for acute thoracolumbar spinal injuries were assessed. We defined the epiconus as the region from the terminal end of the spinal cord to the proximal 1.0 to 2.25 vertebral bodies, the conus medullaris as the region proximal to < 1.0 vertebral bodies, and the cauda equina as the distal part of the nerve roots originating from the spinal cord. On the basis of the distance from the terminal end of the spinal cord to the narrowest level of the spinal canal, the narrowest levels were ordered as follows: the epiconus followed by the conus medullaris and cauda equina. The narrowest levels were the epiconus in 22 patients, conus medullaris in 37 patients, and cauda equina in 25 patients. On admission, significantly more patients had a narrowed epiconus of Frankel grades A-C than a narrowed cauda equina. At the final follow-up, there were no significant differences in neurological recovery among those with epiconus, conus medullaris, or cauda equina syndrome. Anatomically classifying the narrowest lesion is useful for clarifying the differences and similarities among these three syndromes

ACDF with a PEEK cage clinically provides a good outcome with minor donor site morbidity despite unsatisfactory radiological findings―A prospective cohort study of a PEEK cage in stand-alone usage―

Study Design: A prospective cohort study was conducted on patients with anterior cervical decompression and fusion (ACDF) with a polyetheretherketone cage (PEEKc). Background: Advantages of a PEEKc have been proposed in the study. However, benefits of using a PEEKc in ACDF are still controversial. Objective: To investigate the advantages of a PEEKc in ACDF. Materials and Methods: A total of 27 patients was enrolled in the study. The mean age of patients was 55±10 years (mean±standard deviation). The mean duration of symptoms was 17±21 months. Surgery was conducted at C3/4 in 1, C4/5 in 3, C5/6 in 11, C6/7 in 9, C7/T1 in 2, and C5/6/7 in 1 patient. The mean follow-up period was 2.1±1.3 years. Clinical outcomes were analyzed by the Japanese Orthopedic Association Scores (JOA scores) and its recovery rate. Perioperative complications were also investigated. Radiologically, studies were conducted on interbody lordotic angle (IBLA), interbody height (IBH), and bone fusion rates. Results: The JOA score was 14.7±1.4 preoperatively and 16.3±1.3 at the final follow-up. A significant improvement was observed (p<0.05). The mean recovery rate of JOA scores was 74.0±25.0%. The preoperative IBLA was 0.5±6.1°. The mean IBLA at the final follow-up was 1.9±5.6°. The preoperative IBH was 34.2±3.5 mm. The mean IBH at the final follow-up was 34.3±3.5 mm. No significant improvement in IBLA and IBH was observed. A complete union rate at 1 year and 2.3 years (range, 2.0-6.0) after surgery was 29% (8/28 segments) and 61% (11/18 segments). No major complications were observed. Conclusions: Despite an unsatisfactory bone union rate and no significant improvement in IBLA and IBH at the final follow-up, ACDF with a PEEKc clinically provided a stable outcome with less surgical invasion and minor donor-site morbidity

Prevalence of global spinal malalignment and the influence on LBP and HR-QOL in a healthy, nonelderly population. A cross sectional analysis, including bone mineral density, skeletal muscle mass index, and back muscle extensor strength

Background: In healthy, nonelderly populations, prevalence of 3 modifiers of global spinal malalignment (GS-MalAlign) (PT ≧20°, PI-LL≧10°, SVA≧40 mm) remains unknown. The clinical significance has not been determined. The purposes are to disclose the prevalence of the 3 modifiers of GS-MalAlign, and evaluate the influence on LBP, and HR-QOL related to bone mineral density (BMD), skeletal muscle mass index (SMI), and back muscle extensors strength (BMES) in a healthy, nonelderly population. Methods: A mono-centric, cross-sectional survey. Three hundred and 2 participants (18< age <65 years) without ADL disturbance were consecutively enrolled. Sagittal parameters of the spine and the pelvis were measure on whole spine radiograms. BMD and SMI were determined using DEXA. BMES was defined as a maximum extension force at the T4 to T7 level and measured by a strain-gauge dynamotor. LBP was checked through interview. HR-QOL was ascertained by score of Medical Outcome Study Short-Form 36-Health Survey (SF-36v2). Results: The final analysis could be done in 84 females and 179 males. PT≧20°, PI-LL≧10°, and SVA≧40 mm were found in 12% (31/263), 11% (31/263), and 6% (16/263), and each mean value was 25.0 ± 4.0°, 15.3 ± 5.9°, and 52.7 ± 12.2 mm (Mean ± S.D.). Prevalence of LBP was significantly higher in the participants with PI-LL≧10° than with PI-LL<10°; 43% (12/28) versus 21% (49/235) (p<.05). PI-LL≧10° only had an association with LBP (OR: 3.0435, 95% CI, 1.1378–8.141, p<.05). Four 2% of participants (4/263) associated with all 3 modifiers had LBP and a significantly lower mental component summary score of SF-36v2 (p<.05). Conclusions: Some of individuals are associated with GS-MalAlign even in healthy, nonelderly populations. There is a possibility that PI-LL ≧10° results in LBP within a degree of no ADL disturbance, and it is speculated that coexistence of all 3 modifiers of GS-MalAlign would lead to a poor mental HR-QOL