Dynamics of surgical smoke in the operating room during spinal surgery: Comparison of particulate matter 2.5-air concentration between the electric scalpel with and without a smoke evacuation pencil: A cross-sectional study.

BACKGROUND: Surgical smoke is a vaporous by-product generated during tissue incision and cauterization with an electric scalpel. This smoke contains tissue- and blood/vascular-derived substances, bacteria, viruses, and chemical substances. Among them, it contains many fine particles called particulate matter (PM) 2.5, which are harmful and hazardous to the human body. We aimed to investigate the occurrence of PM2.5 in surgical smoke produced during spinal surgery and to evaluate the efficacy of an electric scalpel with a smoke evacuation pencil. METHODS: In this retrospective observational study, 89 patients who underwent spinal surgery between June 2019 and May 2021 were included. A dust monitor was installed in the operating room to measure the PM2.5 air concentration during the surgery. During each surgery, the total amount of PM2.5, the maximum PM2.5 air concentration, the exposure time to PM2.5, and the average value of PM2.5 air concentration from the start to the end of the surgery were calculated. RESULTS: We found that in 29 of the 89 cases (32.6%), the air concentration of PM2.5 increased to a level that could cause health damage during the surgery. Twelve cases (13.4%) reached the level that could cause serious health damage, and 8 cases (9%) reached an emergency warning level. The total amount and the maximum and average levels of PM2.5 were significantly suppressed in the surgery with a smoke evacuation pencil group than in the surgery without a smoke evacuation pencil group. CONCLUSION: We detected hazardous levels of PM2.5 in the air during spinal surgery, highlighting the importance of considering smoke control or reduction during spinal surgery. We recommend using an electric scalpel with a smoke evacuation pencil for regulating PM2.5 levels in the operating room.

Large aortic pseudoaneurysm after fusion surgery for hyperextension-type lumbar fracture in diffuse idiopathic skeletal hyperostosis: illustrative case.

BACKGROUND: This study aimed to report an aortic pseudoaneurysm, a rare but lethal complication, after a spinal fracture in ankylosing spine. OBSERVATIONS: An 83-year-old obese woman presented with dementia and was nonambulatory after a fall. She was transported to the hospital, and imaging showed a hyperextension-type L1 fracture with diffuse idiopathic skeletal hyperostosis (DISH). After posterior fusion surgery using percutaneous pedicle screws, screw loosening was detected 10 days postoperatively. Fracture dislocation was reduced by changing to transdiscal screws and rodding while in the lateral position. However, the anterior opening persisted. Enhanced computed tomography performed at 6 weeks postoperatively showed a large aortic pseudoaneurysm extending into the vertebral fracture site without screw loosening. Neither endovascular aortic repair nor open surgery was applicable. The patient was transferred to a sanatorium and died of pneumonia 5 months postoperatively without aortic aneurysm rupture. LESSONS: An aortic pseudoaneurysm can occur in hyperextension-type spinal fractures in DISH, even after fusion surgery, when the edge of the fracture is in contact with the aortic wall. The anterior opening dislocation should be reduced as much as possible.

Effect of adjuvant therapy with teriparatide in patients with thoracolumbar osteoporotic vertebral fractures who underwent vertebroplasty with posterior spinal fusion.

Teriparatide (TPTD) administration has a potent osteogenic action and promotes the healing of osteoporotic vertebral fractures (OVFs). We aimed to investigate the outcomes of vertebroplasty with posterior spinal fusion (VP + PSF) and determine the impact of perioperative TPTD administration. We included 73 patients (18 male and 55 female patients; mean age: 78 years) with thoracolumbar OVFs who underwent VP + PSF and were followed-up for at least 2 years. Twenty-three patients who received TPTD perioperatively for > 3 months were included in the TPTD group, and the remaining 50 patients were included in the non-TPTD group. Radiographic findings regarding sagittal alignment and clinical outcomes in both groups were compared. The mean duration of TPTD administration was 17.5 ± 5.0 months (range 4-24 months). The mean loss of correction of local kyphosis angle in the TPTD group (4.0°) was lesser than that in the non-TPTD group (7.5°; p < 0.05); however, no significant differences were observed between the groups regarding global sagittal alignment, the occurrence of subsequent vertebral fractures, pedicle screw loosening and treatment-efficacy rates of clinical outcomes. Local kyphosis correction in patients who underwent VP + PSF for OVFs could be maintained through perioperative TPTD administration; however, TPTD administration had little effect on clinical outcomes.

Comparison of surgical smoke between open surgery and laparoscopic surgery for colorectal disease in the COVID-19 era.

BACKGROUND: Surgical smoke during operation is a well-known health hazard for medical staff. This study aimed to investigate the dynamics of surgical smoke during open surgery or laparoscopic surgery for colorectal disease. METHODS: This study quantitated particulate matter (PM) counts as part of surgical smoke in 31 consecutive patients who underwent colectomy at the Niigata City General Hospital using a laser particle counter. Particles were graded by size as ≤ 2.5 µm PM (PM2.5) or > 2.5 µm PM (large PM). Operative procedures were categorized as either open surgery (n = 14) or laparoscopic surgery (n = 17). RESULTS: The median patient age was 72 (range 41-89) years and 58.1% were male. The total PM2.5, PM2.5 per hour, and maximum PM2.5 per minute counts during operation were significantly higher in open surgery than in laparoscopic surgery (P = 0.001, P < 0.001, and P = 0.029, respectively). Large PM counts (total, per hour, and maximum per minute) were also higher in the open surgery group than in the laparoscopic surgery group. The maximum PM2.5 concentration recorded was 38.6 µm/m3, which is considered "unhealthy for sensitive groups" according to the U.S. Environment Protection Agency air quality index standards, if it was a 24-h period mean value. CONCLUSION: Exposure to surgical smoke is lower during laparoscopic surgery than during open surgery for colorectal diseases.

Neoadjuvant teriparatide therapy targeting the osteoporotic spine: influence of administration period from the perspective of bone histomorphometry.

OBJECTIVE: Teriparatide (TPTD) is a potent promoter of early-stage osteogenesis and may be a useful adjuvant therapy to reduce complications related to bone fragility in spinal surgery patients with osteoporosis. However, effective neoadjuvant TPTD therapy regimens remain poorly understood. This study aimed to examine the effect of preoperative TPTD administration on cancellous bone with bone histomorphometry and to clarify the timing of preoperative TPTD administration for patients with spinal fusion and osteoporosis. METHODS: In this longitudinal multicenter study, 57 patients with spinal fusion and osteoporosis, who consented to undergo iliac biopsy, were allocated to the following treatment groups: neoadjuvant TPTD therapy group (n = 42) and no neoadjuvant therapy (NTC) group (n = 15). Patients in the TPTD group were categorized into subgroups on the basis of duration of preoperative TPTD administration, as follows: 1 month (n = 9), 2 months (n = 8), 3 months (n = 9), 4 months (n = 7), and 6 months (n = 9). All patient samples were preoperatively double labeled with tetracycline, and iliac biopsies were performed during spinal fusion surgery. Histomorphometric analyses were performed on nondecalcified, thin-sliced specimens. Specimens were classified on the basis of TPTD administration duration and subsequently compared with those of the NTC group. Postoperative complications and Oswestry Disability Index scores were evaluated at 1 and 2 years after surgery. RESULTS: There were no demographic differences between groups. Mineralizing surface/bone surface, a key parameter of dynamic bone formation, started to increase after 1 month of TPTD administration; this increase became significant after 3 months of administration and peaked at 4 months, with a 6-fold increase relative to that of the NTC group. The patients who received preoperative TPTD for 3 months or more had superior clinical results in terms of the osteoporotic complication rate and Oswestry Disability Index scores, except for bisphosphonate-pretreated patients. CONCLUSIONS: When considering neoadjuvant TPTD therapy, the authors recommend at least 3 months of preoperative administration to provide a more substantial anabolic effect from the early postoperative stage.

Indication for drainage for a hematogenous iliopsoas abscess: Analysis of patients initially treated without drainage.

BACKGROUND: This study aimed to determine the indications for drainage in extended haematogenous iliopsoas abscesses (IPAs), which include both primary and vertebral osteomyelitis-related IPAs. METHODS: Sixty-three IPA patients who were initially treated with only antibiotics and no drainage were enrolled. The success (S) group included patients who were cured without drainage, while the failure (F) group included those who required open or percutaneous drainage or died. RESULTS: Compared with patients in the S group, patients in the F group (n = 15) had a higher incidence of end-stage renal disease on hemodialysis, compromised immunity, vertebral osteomyelitis of the cervicothoracic spine, other musculoskeletal infections, and multilocular abscesses. The IPAs in the F group had larger transverse and longitudinal diameters. In receiver operating characteristic curve analyses for the diameter of IPAs, the most valuable cut-off points predicting the F group were a longitudinal diameter of 5.0 cm (sensitivity, 1.0; specificity, 0.67) and a transverse diameter of 2.3 cm (sensitivity, 0.73; specificity, 0.73). A combination of both diameter cut-offs had high specificity (sensitivity, 0.73; specificity, 0.90). CONCLUSIONS: Drainage should be applied in case of a larger abscess with transverse diameter ≥ 2.3 cm and longitudinal diameter ≥ 5.0 cm. Conversely, IPAs with longitudinal diameter <5 cm do not require drainage. Haemodialysis, compromised immunity, vertebral osteomyelitis of the cervicothoracic spine, and musculoskeletal infections are risk factors of conservative treatment failure.

Rib Hyperostosis as a Risk Factor for Poor Prognosis in Cervical Spine Injury Patients With Diffuse Idiopathic Skeletal Hyperostosis.

STUDY DESIGN: Retrospective multi-center study. OBJECTIVE: To identify the morphological features of costovertebral joints and ribs in surgically managed cervical injury patients with diffuse idiopathic skeletal hyperostosis (DISH) and to examine its impact on their vital prognosis. SUMMARY OF BACKGROUND DATA: Several reports have indicated that DISH is an independent risk factor for mortality after spinal fracture. The reason for the high mortality in cervical injury patients with DISH is unclear, although some reports have suggested a possible association between pulmonary complications and mortality. METHODS: From 1999 to 2017, a total of 50 DISH patients (44 males) with cervical spine injuries who underwent spinal surgery were enrolled (average age 74 yrs). Prognosis and clinical risk factor data were collected; the morphological features of the patients' costovertebral joints and ribs were evaluated with computed tomography. The influence of each proposed risk factor and thoracic morphological feature on mortality was tested with univariate and multivariate analyses. RESULTS: The survival rate at 5 years after surgery was 52.3%. Nineteen (38%) patients died, and the most common cause of death was pneumonia (68%). Costovertebral bone excrescences and rib hyperostosis were found to be thoracic pathognomonic signs; their frequencies were 94% and 82%, respectively, and these conditions occurred in an average of 7.0 joints and 4.7 bones, respectively. The results of the log-rank test showed a significant difference in age, injury severity score (ISS), costovertebral bone excrescences, and rib hyperostosis. The results of age-adjusted multivariate analysis indicated that age (hazard ratio [HR] = 8.65, 95% confidence interval [CI] = 1.10-68.28, P = 0.041) and rib hyperostosis (HR = 3.82, 95% CI = 1.38-10.57, P = 0.010) were associated with mortality. CONCLUSION: Reduced chest wall mobility associated with rib hyperostosis in cervical spine injury patients with DISH leads to a poor prognosis. LEVEL OF EVIDENCE: 3.

Perioperative factors associated with favorable outcomes of posterior decompression and instrumented fusion for cervical ossification of the posterior longitudinal ligament: A retrospective multicenter study.

PURPOSE: Posterior decompression with instrumented fusion (PDF) is a suitable surgical treatment for K-line (-)-type cervical ossification of the posterior longitudinal ligament (OPLL). However, the adequate indications of PDF have not been clarified yet. The purpose of this study was to investigate the surgical results of PDF and perioperative factors that influence the surgical outcome, and to clarify the adequate indications of PDF. METHODS: Twenty-seven patients (21 men and 6 women, mean age: 61.4 years) who were diagnosed with a K-line (-)-type OPLL that was treated with PDF were included in this study. We evaluated these patients clinically and radiologically to investigate the outcomes of PDF and perioperative factors that influence improvements in the Japanese Orthopedic Association (JOA) score. RESULTS: The mean recovery rate of JOA score at the final follow-up examination was 53.3%. In the statistical analysis, the preoperative C2-C7 angle and the C2-C7 angle immediately postoperatively significantly predicted the surgical outcome. The C2-C7 angle immediately postoperatively was the only most important predictor. Using a receiver operating characteristic curve analysis, we found that the cutoff value of the C2-C7 angle immediately postoperatively for good outcomes (recovery rate of JOA score ≥50%) was -2.0°. CONCLUSIONS: PDF for K-line (-)-type OPLL patients with preoperative lordotic alignment can be expected to have favorable outcomes, which is the adequate indication for PDF. Since the C2-C7 angle immediately postoperatively was the most important predictor, the physician should pay attention to maintain the cervical lordotic alignment to enhance the surgical outcomes in surgical planning.

Surgical treatment for osteoporotic thoracolumbar vertebral collapse using vertebroplasty with posterior spinal fusion: a prospective multicenter study.

PURPOSE: The study aimed to investigate the clinical outcomes and limitations after vertebroplasty with posterior spinal fusion (VP+PSF) without neural decompression for osteoporotic vertebral collapse. METHODS: We conducted a prospective multicenter study including 45 patients (12 men and 33 women, mean age: 77.0 years) evaluated between 2008 and 2012. Operation time, blood loss, visual analog scale (VAS) of back pain, neurological status, kyphosis angle in the fused area, and vertebral union of the collapsed vertebra were evaluated. RESULTS: The mean operation time was 162 min and blood loss was 381 mL. The postoperative VAS score significantly improved, and the neurological status improved in 35 patients (83 %), and none of the remaining patients demonstrated a deteriorating neurological status at two years post-operatively. The mean kyphosis angle pre-operatively, immediately post-operatively, and two years post-operatively was 23.8°, 10.7°, and 24.3°, respectively, and there was no significant difference between the angles pre-operatively and two years post-operatively. The extensive correction of kyphosis >16° was a risk factor for a higher correction loss and subsequent fracture. Union of the collapsed vertebra was observed in 43 patients (95 %) at two years post-operatively. CONCLUSIONS: The present study suggests that spinal stabilization rather than neural decompression is essential to treat OVC. Short-segment VP+PSF can achieve a high union rate of collapsed vertebra and provide a significant improvement in back pain or neurological status with less invasive surgery, but has a limit of kyphosis correction more than 16°.

Clinical features, outcomes, and survival factor in patients with vertebral osteomyelitis infected by methicillin-resistant staphylococci.

PURPOSE: To elucidate clinico-radiological features, therapeutic outcomes, and survival factors of vertebral osteomyelitis patients infected by methicillin-resistant staphylococci (MRS). METHODS: Vertebral osteomyelitis patients admitted to the orthopaedic department between 2007 and 2011 (n = 248) were selected for this multicenter study. We compared patients' backgrounds, therapeutic course, and in-hospital mortality between MRS and methicillin-susceptible staphylococci (MSS). We also examined survival factors of vertebral osteomyelitis due to MRS. RESULTS: Sixteen patients of MRS vertebral osteomyelitis and 55 patients of MSS were included in this study. In MRS vertebral osteomyelitis, the rates of comorbid diabetes mellitus, involvement of >2 vertebral bodies, in-hospital mortality, and operation of surgical debridement were higher compared to those in MSS vertebral osteomyelitis. Univariate analysis showed that operation of surgical debridement was a factor related to survival in MRS patients. CONCLUSIONS: Higher rate of comorbid diabetes mellitus, involvement of >2 vertebral bodies, in-hospital mortality, and performing surgical debridement are peculiar features of MRS vertebral osteomyelitis compared to MSS vertebral osteomyelitis. If patients with MRS vertebral osteomyelitis respond poorly to antibiotic therapy, it might be better to consider surgical debridement not to lose an opportunity of operation due to exacerbation of systemic conditions.

Polymethylmethacrylate augmentation of pedicle screws increases the initial fixation in osteoporotic spine patients.

STUDY DESIGN: A retrospective comparative study. OBJECTIVES: To investigate the clinical efficacy of polymethylmethacrylate (PMMA) augmentation in vertebral pseudarthrosis after osteoporotic vertebral fractures. SUMMARY OF BACKGROUND DATA: Despite being the most rigid form of posterior instrumentation, pedicle screws sometimes achieve poor initial fixation primarily in patients with osteoporosis. One method for improving pedicle screw fixation in osteoporotic spines is pedicle augmentation using bone cement such as PMMA. Although various biomechanical studies of osteoporotic spines have shown improved pullout strength of pedicle screws augmented with bone cement, there have been few studies that have examined the clinical significance of PMMA augmentation. METHODS: Thirty-eight patients with posterior fusion using pedicle screws for vertebral pseudarthrosis after osteoporotic vertebral fracture were included in the study. The level of fracture ranged from T7 to L5. The mean follow-up period was 31 months. Patients were divided into 2 groups: those with posterior instrumentation using pedicle screws augmented with PMMA (group C, N=17) and those without PMMA augmentation (group NC, N=21). Clinical and radiographic results for the 2 groups were compared. RESULTS: With the exception of osteoporotic status, there were no significant differences in the baseline data of the 2 groups. The incidence of clear zones around the pedicle screws was significantly suppressed in group C compared with group NC (29.4% vs. 71.4%). Correction loss was significantly decreased (3 degrees vs. 7.2 degrees) and fusion rate was significantly higher in group C (94.1% vs. 76.1%). Back pain improved in 64.7% of the group C patients. There were no perioperative complications related to the PMMA cement in group C. CONCLUSIONS: Reinforcement of pedicle screws using PMMA augmentation may be a feasible surgical technique for osteoporotic spines.

The Wnt co-receptor LRP5 is essential for skeletal mechanotransduction but not for the anabolic bone response to parathyroid hormone treatment.

The cell surface receptor, low-density lipoprotein receptor-related protein 5 (LRP5) is a key regulator of bone mass. Loss-of-function mutations in LRP5 cause the human skeletal disease osteoporosis-pseudoglioma syndrome, an autosomal recessive disorder characterized by severely reduced bone mass and strength. We investigated the role of LRP5 on bone strength using mice engineered with a loss-of-function mutation in the gene. We then tested whether the osteogenic response to mechanical loading was affected by the loss of Lrp5 signaling. Lrp5-null (Lrp5-/-) mice exhibited significantly lower bone mineral density and decreased strength. The osteogenic response to mechanical loading of the ulna was reduced by 88 to 99% in Lrp5-/- mice, yet osteoblast recruitment and/or activation at mechanically strained surfaces was normal. Subsequent experiments demonstrated an inability of Lrp5-/- osteoblasts to synthesize the bone matrix protein osteopontin after a mechanical stimulus. We then tested whether Lrp5-/- mice increased bone formation in response to intermittent parathyroid hormone (PTH), a known anabolic treatment. A 4-week course of intermittent PTH (40 microg/kg/day; 5 days/week) enhanced skeletal mass equally in Lrp5-/- and Lrp5+/+ mice, suggesting that the anabolic effects of PTH do not require Lrp5 signaling. We conclude that Lrp5 is critical for mechanotransduction in osteoblasts. Lrp5 is a mediator of mature osteoblast function following loading. Our data suggest an important component of the skeletal fragility phenotype in individuals affected with osteoporosis-pseudoglioma is inadequate processing of signals derived from mechanical stimulation and that PTH might be an effective treatment for improving bone mass in these patients.