Association between occupational testicular radiation exposure and lower male sex ratio of offspring among orthopedic surgeons.

BACKGROUND: Exposure to occupational radiation can lower the male sex ratio. However, specific radiation exposure to the testes has not been evaluated. OBJECTIVE: This study aimed to examine the association between testicular radiation exposure and lower male sex ratio in children. METHODS: A comprehensive questionnaire survey was administered to 62 full-time male doctors with children aged < 10 years at 5 hospitals. Based on the possibility of testicular radiation exposure 1 year before the child's birth, participants were assigned to 3 groups as follows: RT (orthopedic surgery), RNT (cardiology/neurosurgery), and N (others). Intergroup differences in the proportion of female children were ascertained, and the female sex ratio (number of female/total number) of each group was compared against the standard value of 0.486. Multivariate logistic regression analysis with a generalized estimating equation was used to model the effects on the probability of female birth while controlling for the correlation among the same fathers. RESULTS: The study population included 62 fathers and 109 children, 49 were female: 19/27, 11/30, and 19/52 in the RT, RNT, and N group, respectively; the RT group had the highest proportion of females (p = 0.009). The p values for comparisons with the standard sex ratio (0.486) were 0.02, 0.19, and 0.08 for the RT, RNT, and N groups, respectively. Based on the N group, the adjusted odds ratios for the child to be female were 4.40 (95% confidence interval 1.60-2.48) and 1.03 (0.40-2.61) for the RT and RNT groups, respectively. CONCLUSIONS: Our results imply an association between testicular radiation exposure and low male sex ratio of offspring. Confirmatory evidence is needed from larger studies which measure the pre-conceptional doses accumulated in various temporal periods, separating out spermatogonial and spermatid effects.

A case report of spondylectomy with circumference reconstruction for aggressive vertebral hemangioma covering the whole cervical spine (C4) with progressive spinal disorder.

PURPOSE: To describe the surgical experience of spondylectomy and spinal reconstruction for aggressive vertebral hemangioma (VH) induced at the C4 vertebra. No reports have described surgical strategy in cases covering an entire cervical vertebra presenting with progressive myelopathy. METHODS: A 28-year-old man presented with rapidly progressing skilled motor dysfunction and gait disorder. The Japanese Orthopedic Association (JOA) score was 6. Radiography showed a honeycomb appearance for the entire circumference of the C4 vertebra. Spinal computed tomography and magnetic resonance imaging showed vertebral tumor with extraosseous extension causing spinal cord compression. Results of diagnostic imaging were strongly suggestive of VH. Transarterial embolization of the spinal body branch was performed first to decrease intraoperative bleeding, followed by cervical posterior fixation to stabilize the unstable segment and excision biopsy to obtain a definitive diagnosis. After definitive diagnosis of cavernous hemangioma, two-stage surgery (anterior and posterior) was performed to complete total spondylectomy and 360° spinal reconstruction. RESULTS: Despite multiple operations, JOA scores were 8.5 after posterior fixation, 10.5 after anterior surgery, 11 after final surgery and 16 on postoperative day 90. The patient acquired excellent clinical results without complications and returned to society. CONCLUSIONS: The present three-stage surgery comprising fixation, biopsy, and final spondylectomy with circumferential fusion from anterior and posterior approaches may offer a useful choice for aggressive VH covering the entire cervical spine with rapidly progressive myelopathy.

Accuracy of Percutaneous Pedicle Screw Insertion Technique with Conventional Dual Fluoroscopy Units and a Retrospective Comparative Study Based on Surgeon Experience.

Study Design Retrospective comparative study. Objective To evaluate the accuracy of percutaneous pedicle screw (PPS) placement and intraoperative imaging time using dual fluoroscopy units and their differences between surgeons with more versus less experience. Methods One hundred sixty-one patients who underwent lumbar fusion surgery were divided into two groups, A (n = 74) and B (n = 87), based on the performing surgeon's experience. The accuracy of PPS placement and radiation time for PPS insertion were compared. PPSs were inserted with classic technique under the assistance of dual fluoroscopy units placed in two planes. The breach definition of PPS misplacement was based on postoperative computed tomography (grade I: no breach; grade II: <2 mm; grade III: ≤2 to <4 mm). Results Of 658 PPSs, only 21 screws were misplaced. The breach rates of groups A and B were 3.3% (grade II: 3.4%, grade III: 0%) and 3.1% (grade II: 2.6%, grade III: 0.6%; p = 0.91). One patient in grade III misplacement had a transient symptom of leg numbness. Median radiation exposure time during PPS insertion was 25 seconds and 51 seconds, respectively (p < 0.01). Conclusions Without using an expensive imaging support system, the classic technique of PPS insertion using dual fluoroscopy units in the lumbar and sacral spine is fairly accurate and provides good clinical outcomes, even among surgeons lacking experience.

18F-FDG-PET/CT better localizes active spinal infection than MRI for successful minimally invasive surgery.

BACKGROUND: Surgical debridement is often required to treat spinal infections. Successful surgery requires accurate localization of the active infections, however, current imaging technique still requires surgeons' experience to narrow the surgical fields to achieve less invasive procedures. PURPOSE: To investigate the use of F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) for successful surgical planning. MATERIAL AND METHODS: Nine patients with suspected spinal infection underwent magnetic resonance imaging (MRI) and FDG-PET/CT before surgery to locate active foci of infections. The spinal structures were divided into seven compartments at each intervertebral disc level for a total of 315 compartments investigated. The same classification system was used to design operating fields for histological correlation. RESULTS: FDG-PET/CT diagnosed fewer compartments as active infection (34 compartments, 10.8%) than MRI (62 compartments, 19.7%, P = 0.002). Surgical exploration was performed in 49 compartments, and demonstrated active infection in 25 compartments. The sensitivity / specificity of FDG-PET/CT was 100% / 79%, respectively, which was superior to those of MRI, 76% / 42%. Foci of active infection showed hypermetabolic activity with a SUVmax of 7.1 ± 2.6 (range, 3.0-12.7). Receiver operating characteristic (ROC) analysis indicated an optimal threshold for active spinal infection at a SUVmax of 4.2, corresponding to a sensitivity of 90.3% and specificity of 91.2%. CONCLUSION: FDG-PET/CT demonstrated limited areas of abnormality allowing accurate delineation, and is thus useful to narrow the surgical fields. Since overall diagnostic accuracy of FDG-PET/CT was superior to that of MRI, FDG-PET/CT is a useful technique to narrow the surgical field for successful less invasive surgery.