Journal of Orthopaedic Science

In 64 surgically treated herniated lumbar intervertebral discs, we performed histopathological studies of neovascularization in the outermost layer of the herniated mass in various types of hernia. We obtained specimens separately from the capsule tissue covering the herniated mass and the inner tip tissue of the herniated mass for comparison. Histologically, in most cases, the capsule tissue was the outermost layer of the annulus fibrosus or posterior longitudinal ligament, and the inner tip tissue was the nucleus pulposus. In the capsule tissue, newly formed small blood vessels were present in 73.4% of the total cases examined, regardless of the hernia type. However, the frequency and degree of such vessels in the tip tissue were significantly higher in hernias that perforated the posterior longitudinal ligament than in those that did not. When the intervertebral disc herniates, new blood vessels proliferate in the capsule of the hernial tissue. At the stage when the hernial capsule tissue is still present, these vessels were observed to have difficulty reaching the inner tip portion. These findings suggest that when the nucleus pulposus portion of the herniated mass perforates the posterior longitudinal ligament, it may be subject to a stronger neovascularization reaction.

No studies have reported on osteotomies utilizing a navigation system in congenital scoliosis surgery. This study aimed to evaluate the surgical outcomes of eight patients with congenital scoliosis or kyphoscoliosis due to hemivertebrae treated by computer-assisted hemivertebral resection using only a posterior approach. Eight consecutive patients (two scoliotics and six kyphoscoliotics) managed by computer-assisted hemivertebral resection using only a posterior approach with transpedicular instrumentation were investigated retrospectively. A CT-based navigation system was used to confirm the positions of the vertebra, spinal cord and aorta in real-time when we inserted a pedicle screw and conducted the osteotomy. The mean patient age at surgery was 18 years (range 11–41 years). The mean follow-up was 46 months (range 18–84 months). Before surgery, the mean kyphotic curve was 55.8° (range 26–83°), and the mean scoliotic curve was 50.0° (range 36–62°). At the final follow-up period, the curves averaged 23.2° (range 15–40°) and 31.6° (range 21–44°), respectively, yielding kyphotic angle corrections of 32.7° (range 11–58°) and Cobb angle correction rates of 36.8% (range 24.1–48.3%). A total of 72 pedicle screws were inserted with the navigation system, and two screws revealed a perforating pedicle. No neurovascular complications occurred. The perforation rate was 2.8%. Hemivertebral resection via a single posterior approach is less invasive than combined anterior and posterior approaches; however, this procedure increases the risk of spinal cord and vascular injuries. Computer-assisted hemivertebral resection enables safe and accurate performance of a hemivertebral resection via a single posterior approach.

The Quick Disability of the Arm, Shoulder, and Hand (QuickDASH) questionnaire is a region-specific, self-administered questionnaire, which consists of a disability/symptom (QuickDASH-DS) scale, and the same two optional modules, the work (DASH-W) and the sport/music (DASH-SM) modules, as the DASH. After the Japanese version of DASH (DASH-JSSH) was cross-culturally adapted and developed, we made the Japanese version of QuickDASH (QuickDASH-JSSH) by extracting 11 out of 30 items of the DASH-JSSH regarding disability/symptoms. The purpose of this study was to test the reliability, validity, and responsiveness of QuickDASH-JSSH. A series of 72 patients with upper extremity disorders completed the QuickDASH-JSSH, the 36-Item Short-Form Health Survey (SF-36), and the Visual Analog Scale (VAS) for pain. Thirty-eight of the patients were reassessed for test–retest reliability 1 or 2 weeks later. Reliability was investigated by the reproducibility and internal consistency. To analyze the validity, a principal component analysis and the correlation coefficients between the QuickDASH-JSSH and the SF-36 were obtained. The responsiveness was examined by calculating the standardized response mean (SRM; mean change/SD) and effect size (mean change/SD of baseline value) after carpal tunnel release of the 17 patients with carpal tunnel syndrome. Cronbach’s alpha coefficient in the QuickDASH-DS was 0.88. The intraclass correlation coefficient (ICC) for the same was 0.82. The unidimensionality of the QuickDASH-DS was confirmed. The correlation coefficients between the QuickDASH-DS and the DASH-DS, DASH-W, or the DASH-SM were 0.92, 0.81, or 0.76, respectively. The correlation coefficients between the QuickDASH-DS score and the subscales of the SF-36 ranged from −0.29 to −0.73. The correlation coefficient between the QuickDASH-DS score and the VAS for pain was 0.52. The SRM/effect size of QuickDASH-DS was −0.54/−0.37, which indicated moderate sensitivity. The Japanese version of QuickDASH has equivalent evaluation capacities to the original QuickDASH.