The Anatomical Relationship Between the Cervical Nerve Roots, Intervertebral Discs and Bony Cervical Landmark for Posterior Endoscopic Cervical Foraminotomy and Discectomy: A Cadaveric Study.

STUDY DESIGN: Cadaveric anatomical studies. OBJECTIVE: This study aims to investigate the anatomical relationship between bony landmark "V point", dural sac, nerve roots, and intervertebral disc for improving operative outcomes and decreasing post-operative complications in posterior endoscopic cervical foraminotomy or discectomy (PECF or PECD). METHOD: 10 soft adult cadavers were studied. We measured the distance of the V point to the lateral margin of dural sac, V point to the inferior border of intervertebral disc, and the inferior border of cervical nerve root to the inferior border of intervertebral disc. Then we calculated the mean of distance from V point to the inferior border of cervical nerve root. RESULT: The mean distance from the V point to the lateral margin of dural sac from C3/4 to C7/T1 ranged from 3.1 ± 1.38 mm to 3.37 ± 1.46 mm. The mean distances from V point to the inferior border of intervertebral disc from C3/4 to C7/T1 were .19 ± 1.16 mm at C3/4, .45 ± 1.23 mm at C4/5, .43 ± 1.01 at C5/6, -.43 ± 1.86 mm at C6/7 and -1.5 ± 1.2 mm at C7/T1. The mean distance between V point and the inferior border of cervical nerve root from C3/4 to C7/T1 showed all positive value, ranging from .06 ± 1.18 mm to 4.45 ± 2.57 mm, increasing caudally. CONCLUSION: In performing PECF or PECD, a 3-4 mm radius of bone removal should be enough for exposure and neural decompression at C3/4 to C5/6. At C6/7 and C7/T1 a more extensive bone cut of more than 4 mm is recommended, especially in cranial direction.

A clinical prediction model to differentiate tuberculous spondylodiscitis from pyogenic spontaneous spondylodiscitis.

BACKGROUND: Microbiological diagnosis of tuberculous spondylodiscitis (TS) and pyogenic spontaneous spondylodiscitis (PS) is sometime difficult. This study aimed to identify the predictive factors for differentiating TS from PS using clinical characteristics, radiologic findings, and biomarkers, and to develop scoring system by using predictive factors to stratify the probability of TS. METHODS: A retrospective single-center study. Demographics, clinical characteristics, laboratory findings and radiographic findings of patients, confirmed causative pathogens of PS or TS, were assessed for independent factors that associated with TS. The coefficients and odds ratio (OR) of the final model were estimated and used to construct the scoring scheme to identify patients with TS. RESULTS: There were 73 patients (51.8%) with TS and 68 patients (48.2%) with PS. TS was more frequently associated with younger age, history of tuberculous infection, longer duration of symptoms, no fever, thoracic spine involvement, ≥3 vertebrae involvement, presence of paraspinal abscess in magnetic-resonance-image (MRI), well-defined thin wall abscess, anterior subligamentous abscess, and lower biomarker levels included white blood cell (WBC) counts, erythrocyte-sedimentation-rate (ESR), neutrophil fraction, and C-reactive protein (all p < 0.05). Multivariate logistic regression analysis revealed significant predictors of TS included WBC ≤9,700/mm3 (odds ratio [OR] 13.11, 95% confidence interval [CI] 4.23-40.61), neutrophil fraction ≤78% (OR 4.93, 95% CI 1.59-15.30), ESR ≤92 mm/hr (OR 4.07, 95% CI 1.24-13.36) and presence of paraspinal abscess in MRI (OR 10.25, 95% CI 3.17-33.13), with an area under the curve of 0.921. The scoring system stratified the probability of TS into three categories: low, moderate, and high with a TS prevalence of 8.1%, 29.6%, and 82.2%, respectively. CONCLUSIONS: This prediction model incorporating WBC, neutrophil fraction counts, ESR and presence of paraspinal abscess accurately predicted the causative pathogens. The scoring scheme with combination of these biomarkers and radiologic features can be useful to differentiate TS from PS.

"Platelet-Rich Plasma" epidural injection an emerging strategy in lumbar disc herniation: a Randomized Controlled Trial.

BACKGROUND: Lumbar herniated disc (HNP) is mainly treated by conservative management. Epidural steroid injection (ESI) has been an option to treat failed cases prior to surgery. Triamcinolone has been widely used due to its efficacy in bringing about pain reduction for up to three months. However, several reports have shown some severe adverse events. Platelet-rich plasma (PRP) is made from blood through centrifugation. Several studies supported the potential short to long-term effects, and safety of PRP injection in treating HNP. The study objective was to evaluate the efficacy of PRP in treatment of single-level lumbar HNP in comparison to triamcinolone. METHODS: Thirty patients were treated by transforaminal epidural injections. PRP was obtained from 24 ml venous blood through standardized double-spin protocol. Participants included fifteen patients each being in triamcinolone and PRP groups. The same postoperative protocols and medications were applied. The visual analogue scale of leg (LegVAS), collected at baseline, 2, 6, 12, and 24 weeks, was the primary outcome. The BackVAS, Oswestry Disability Index (ODI), adverse event, and treatment failure were the secondary endpoints. RESULTS: Platelet ratio of PRP in fifteen patients was 2.86 ± 0.85. Patients treated by PRP injections showed statistically and clinically significant reduction in LegVAS at 6, 12, and 24 weeks, and in ODI at 24 weeks. It demonstrated comparable results on other aspects. No adverse event occurred in either group. CONCLUSION: Noncommercial epidural double-spin PRP yielded superior results to triamcinolone. Due to its efficacy and safety, the procedure is recommended in treating single level lumbar HNP. TRIAL REGISTRATION: NCT, NCT05234840. Registered 1 January 2019, https://clinicaltrials.gov/ct2/show/record/NCT05234840 .

Survey research of patient's preference on choosing microscopic or endoscopic spine surgery for lumbar discectomy.

BACKGROUND: There are several surgical methods of lumbar discectomy which provide the similar clinical outcomes. There is no clear evidence for how to select the procedures. To better understand the patient's opinion and decision process in the selection of surgical methods between microscopic lumbar discectomy (MLD) and endoscopic lumbar discectomy (ELD). METHODS: A cross-sectional survey study. Summary information sheet was created by reviewing the comparative literatures, and tested for quality and bias. Participants read the summary information sheet then were asked to complete the anonymous questionnaire. RESULTS: Seventy-six patients (71%) of patients who had no experience in lumbar discectomy selected ELD while 31 patients (29%) selected MLD. There were significant differences of score between patients who selected MLD and ELD in this group for wound size, anesthetic method, operative time, blood loss and length of stay (P< 0.05). In patients who had experience in discectomy group, 22 patients (76%) who underwent MLD still selected MLD if they could select surgical methods again for themselves, while 24 patients (96%) who underwent ELD still selected ELD if they could select again. The most important factor in patients who selected MLD was outcomes of treatment. The most important factor in patients who selected ELD was wound size. There were significant differences of scores between patients who selected MLD and ELD in this group for wound size, anesthetic method, operative time, complication, cost and length of stay (P< 0.05). CONCLUSIONS: About two thirds of the participants preferred ELD after reading the summary evidence information. The most important factor in MLD group was outcomes of treatment while the most important factor in ELD group was wound size.

Predictive factors for respiratory failure and in-hospital mortality after surgery for spinal metastasis.

PURPOSE: Spinal metastasis surgeries carry substantial risk of complications. PRF is among complications that significantly increase mortality rate and length of hospital stay. The risk factor of PRF after spinal metastasis surgery has not been investigated. This study aims to identify the predictors of postoperative respiratory failure (PRF) and in-hospital death after spinal metastasis surgery. METHODS: We retrospectively reviewed consecutive patients with spinal metastasis surgically treated between 2008 and 2018. PRF was defined as mechanical ventilator dependence > 48 h postoperatively (MVD) or unplanned postoperative intubation (UPI). Collected data include demographics, laboratory data, radiographic and operative data, and postoperative complications. Stepwise logistic regression analysis was used to determine predictors independently associated with PRFs and in-hospital death. RESULTS: This study included 236 patients (average age 57 ± 14 years, 126 males). MVD and UPI occurred in 13 (5.5%) patients and 13 (5.5%) patients, respectively. During admission, 14 (5.9%) patients had died postoperatively. Multivariate logistic regression analysis revealed significant predictors of MVD included intraoperative blood loss > 2000 mL (odds ratio [OR] 12.28, 95% confidence interval [CI] 2.88-52.36), surgery involving cervical spine (OR 9.58, 95% CI 1.94-47.25), and ASA classification ≥ 4 (OR 6.59, 95% CI 1.85-23.42). The predictive factors of UPI included postoperative sepsis (OR 20.48, 95% CI 3.47-120.86), central nervous system (CNS) metastasis (OR 10.21, 95% CI 1.42-73.18), lung metastasis (OR 7.18, 95% CI 1.09-47.4), and postoperative pulmonary complications (OR 6.85, 95% CI 1.44-32.52). The predictive factors of in-hospital death included postoperative sepsis (OR 13.15, 95% CI 2.92-59.26), CNS metastasis (OR 10.55, 95% CI 1.54-72.05), and postoperative pulmonary complications (OR 9.87, 95% CI 2.35-41.45). CONCLUSION: PRFs and in-hospital death are not uncommon after spinal metastasis surgery. Predictive factors for PRFs included preoperative comorbidities, intraoperative massive blood loss, and postoperative complications. Identification of risk factors may help guide therapeutic decision-making and patient counseling.

Correlation between shape-closed femoral stem design and bone cement implantation syndrome in osteoporotic elderly femoral neck fracture undergoing cemented hip arthroplasty: A retrospective case-control study in 128 patients.

BACKGROUND: Bone cement implantation syndrome (BCIS) is a serious and potentially fatal complication especially in patients with osteoporotic femoral neck fracture (OFNF) undergoing cemented hip arthroplasty (CHA). Recent studies showed that the shape-closed femoral stem profile could lead to a significant increase of the intramedullary pressure during cementation and prosthesis insertion. This study aimed to (1) correlate the use of shaped-closed femoral stem and other perioperative risk factors with severe grade of BCIS grade 2 or 3: BCIS gr2/3, and (2) identify the prevalence of BCIS in the elderly patients with OFNF and treated with CHA. HYPOTHESIS: Large wedge-shaped (or "shape-closed") femoral stem design would significantly associate with BCIS gr2/3 in the elderly patients who sustained OFNF and underwent CHA. PATIENTS AND METHODS: A total of 128 OFNF patients, who aged over 75years and underwent CHA were retrospectively reviewed and then allocated into 2 groups: SC Group (use shape-closed femoral stem, n=40) and FC Group (use force-closed femoral stem, n=88). BCIS was grading in all patients according to Donaldson classification. Perioperative data between the patients with BCIS-gr2/3 and those with BCIS grade 0 or 1 (BCIS-gr0/1) were compared. Multiple logistic regression analysis was used to identify predictive factors for BCIS-gr2/3. RESULTS: The prevalence of overall BCIS and BCIS-gr2/3 was 32.8% (n=42) and 6.2% (n=8), respectively. The total in-hospital and 1-year mortality rates were 2.3% and 4.7%, respectively. The major perioperative complication in patients with BCIS-gr2/3 was significantly higher compared to those in patients with BCIS-gr0/1 (62.5% vs. 10.0%, p=0.001). Multivariate analysis showed that age>90years (OR=9.4, 95% CI: 1.4-62.9, p=0.02), preinjury Parker mobility score<4 (OR=48.8; 95% CI: 2.7-897.2, p=0.008) and shape-closed femoral stem used (OR=19.1; 95% CI: 1.8-204.5, p=0.01) were the significant independent predictors for BCIS-gr2/3 in these patients. CONCLUSION: BCIS in OFNF patients undergoing CHA is common and associates with a high major perioperative complication rate. Our initial hypothesis is validated as the patients at risk for BCIS-gr2/3 are those whose CHA procedures use a shape-closed femoral stem design and with extreme age, and having poor preinjury ambulatory status. Therefore, we recommended using cementless stem as the first option in OFNF. However, if CHA is needed, strict guideline for cement insertion should be followed with force-closed stem application to avoid the risk of BCIS-gr2/3. LEVEL OF EVIDENCE: III; retrospective case-control study.

Validation of Traditional Prognosis Scoring Systems and Skeletal Oncology Research Group Nomogram for Predicting Survival of Spinal Metastasis Patients Undergoing Surgery.

Background: Many scoring systems that predict overall patient survival are based on clinical parameters and primary tumor type. To date, no consensus exists regarding which scoring system has the greatest predictive survival accuracy, especially when applied to specific primary tumors. Additionally, such scores usually fail to include modern treatment modalities, which influence patient survival. This study aimed to evaluate both the overall predictive accuracy of such scoring systems and the predictive accuracy based on the primary tumor. Methods: A retrospective review on spinal metastasis patients who were aged more than 18 years and underwent surgical treatment was conducted between October 2008 and August 2018. Patients were scored based on data before the time of surgery. A survival probability was calculated for each patient using the given scoring systems. The predictive ability of each scoring system was assessed using receiver operating characteristic analysis at postoperative time points; area under the curve was then calculated to quantify predictive accuracy. Results: A total of 186 patients were included in this analysis: 101 (54.3%) were men and the mean age was 57.1 years. Primary tumors were lung in 37 (20%), breast in 26 (14%), prostate in 20 (10.8%), hematologic malignancy in 18 (9.7%), thyroid in 10 (5.4%), gastrointestinal tumor in 25 (13.4%), and others in 40 (21.5%). The primary tumor was unidentified in 10 patients (5.3%). The overall survival was 201 days. For survival prediction, the Skeletal Oncology Research Group (SORG) nomogram showed the highest performance when compared to other prognosis scores in all tumor metastasis but a lower performance to predict survival with lung cancer. The revised Katagiri score demonstrated acceptable performance to predict death for breast cancer metastasis. The Tomita and revised Tokuhashi scores revealed acceptable performance in lung cancer metastasis. The New England Spinal Metastasis Score showed acceptable performance for predicting death in prostate cancer metastasis. SORG nomogram demonstrated acceptable performance for predicting death in hematologic malignancy metastasis at all time points. Conclusions: The results of this study demonstrated inconsistent predictive performance among the prediction models for the specific primary tumor types. The SORG nomogram revealed the highest predictive performance when compared to previous survival prediction models.

Effectiveness of prophylactic double-looped wiring in cementless Hip arthroplasty: A biomechanical study in osteoporotic bone model using impaction simulation system.

BACKGROUND: Periprosthetic femoral fracture (PFF) is well-known complication in cementless hip arthroplasty (HA), especially in the elderly with osteoporosis. To prevent intraoperative PFFs during HA, prophylactic cerclage wiring on the calcar area during femoral broaching and implant insertion is recommended. However, biomechanical data on the benefits of cerclage wiring in osteoporotic bone during impaction are limited and controversial. This study aimed to assess the efficacy of prophylactic double-looped cerclage wiring (PDLCW) during femoral broaching in the osteoporotic bone model with an impaction simulation system. METHODS: Fifteen osteoporotic femur models were prepared and allocated to three groups; control group (no cerclage), PW group (received PDLCW), and CC+PW group (prepared as having calcar crack and received PDLCW). All femurs were broached under impaction force that sequentially increased until the visible fracture or calcar crack propagation was visible. The primary outcomes were mallet impaction force (MIF-CF) and mallet velocity (MV-CF) at the time of calcar fracture. The secondary outcomes were calcar fracture pattern and subsidence during calcar fracture (S-CF). RESULTS: PW group showed a significant increase in average MIF-CF, by 40.4% and 120.2% (p<0.001) compared to the control and CC+PW groups, respectively. The average MV-CF in PW group was also significantly greater, 13.1% and 64.6% (p<0.001), compared to the control and CC+PW groups, respectively. Control group revealed significantly greater incidence of complete calcar fracture (60% vs. 0% vs. 0%, p = 0.024), and the highest S-CF compared to those in the PW and CC+PW groups (10.6 ±â€¯6.0 mm, 6.7 ±â€¯4.4 mm, and 1.3 ±â€¯2.0 mm, p = 0.020). CONCLUSIONS: This study showed that PDLCW significantly improved hoop stress resistance by increasing the calcar fracture threshold related to mallet impaction, decreasing the risk of complete calcar fracture.

Prolonged durability of extensive contiguous spinal metastasis stabilization in non-small cell lung cancer patients receiving targeted therapy: two case reports and a literature review.

MINI-ABSTRACT: In this report, we present two cases of contiguous spinal metastatic disease in non-small cell lung cancer patients who achieved prolonged survival and stable spinal fixation after treatment with EGFR TKIs.

Spinal metastasis: narrative reviews of the current evidence and treatment modalities.

The treatment for spinal metastasis has evolved significantly during the past decade. An advancement in systemic therapy has led to a prolonged overall survival in cancer patients, thus increasing the incidence of spinal metastasis. In addition, with the improved treatment armamentarium, the prediction of patient survival using traditional prognostic models may have limitations and these require the incorporation of some novel parameters to improve their prognostic accuracy. The development of minimally-invasive spinal procedures and minimal access surgical techniques have facilitated a quicker patient recovery and return to systemic treatment. These modern interventions help to alleviate pain and improve quality of life, even in candidates with a relatively short life expectancy. Radiotherapy may be considered in non-surgical candidates or as adjuvant therapy for improving local tumour control. Stereotactic radiosurgery has facilitated this even in radioresistant tumours and may even replace surgery in radiosensitive malignancies. This narrative review summarizes the current evidence leading to the paradigm shifts in the modern treatment of spinal metastasis.

Development of prediction model for osteoporotic vertebral compression fracture screening without using clinical risk factors, compared with FRAX and other previous models.

This study developed a prediction model to assess the need for asymptomatic osteoporotic vertebral compression fracture (OVCF) screening in women without using clinical risk factors. Our results demonstrated that the combination of age, height loss, and femoral neck T-score can predict OVCF comparable to previous models, including FRAX. PURPOSE: Osteoporotic vertebral compression fracture (OVCF) is a major fracture in osteoporosis patients. Early detection of OVCF can reduce the risk of subsequent fractures and death. Many existing diagnostic tools can screen for the risk of osteoporotic fracture but none aim to identify OVCF. The objective of this research is to study a predictive model for capturing OVCF and compare it with previous models. METHODS: A retrospective review was conducted that included women aged ≥ 50 years who underwent dual-energy X-ray absorptiometry and vertebral fracture screening between 2012 and 2019. The data included age, height, weight, history of height loss (HHL), and bone mass density (BMD). Receiver operating characteristic analysis and univariate and multivariate logistic regression were performed. The predictive OVCF model was formulated, and the result was compared to other models. RESULTS: A total of 617 women, a 179 of which had OVCFs, were eligible for analysis. Multivariate regression analysis showed age > 65, height loss > 1.5 cm, and femoral neck T-score < -1.7 as independent risk factors for OVCF. This model revealed comparable performance with FRAX. The model without BMD revealed superior performance to FRAX and other standard osteoporosis assessment models. CONCLUSIONS: BMD and vertebral fracture screening should be eligible for individual women age > 65 years with an HHL more than 1.5 cm, regardless of BMD. Vertebral fracture assessment should be additionally conducted on these women with a femoral neck T-score less than -1.7.

Novel questionnaire to enhance brace wear adherence in patients with adolescent idiopathic scoliosis and the relationship of the quality of life.

Bracing is an effective non-operative treatment, in patients with adolescent idiopathic scoliosis (AIS). The relationship between patients' quality of life (QOL) and brace wear adherence has been reported. This study aims to determine brace wear adherence for AIS patients with novel questionnaire. A nested case-control study was conducted, included patient age 10-18 years, coronal Cobb angle 20-50°, and Risser grade 0-3. Correlation between patients' QOL and the average hours of daily brace-wear were determined. Patients were divided into 3 groups based on brace wear adherence and were compared. QOL domains associated with the incompleteness of brace-wearing were determined by Cox proportional-hazards regression. Mean age of patients was 13.3 years (range 11-17.3 years) with initial Cobb angle of 33.5° (range 20-48°). There were significant negative correlations between total QOL scores and brace wearing time. Increased social domain scores was significantly associated with less brace wearing time (HR 1.5, 95% CI 1.12-2.04). Significant correlations between patients' QOL and the average hours per day of brace wear. Poor social QOL have a significant impact on brace wear adherence.

Efficacy of Periarticular Multimodal Drug Injection Without NSAIDs in Elderly Patients With Displaced Femoral Neck Fractures Undergoing Bipolar Hemiarthroplasty: A Prospective Triple-Blinded RCT.

Introduction Recently, periarticular multimodal drug injection (PMDI) has demonstrated the ability to significantly reduce early postoperative pain with hip fractures in the elderly. Nonetheless, data on PMDI without non-steroidal anti-inflammatory drugs (NSAIDs) in these patients are still doubtful. The current study has evaluated the effect of PMDI with NSAIDs in elderly femoral neck fractures (FNFs) underlying bipolar hip arthroplasty (BHA). Materials and methods A prospective triple-blinded randomized controlled trial (RCT) was conducted in 28 elderly FNFs undergoing BHA. They were randomized into two groups: PMDI group (n=14), which received intraoperative PMDI (50-mL solution of 100-mg bupivacaine, 10-mg morphine, 300-mcg epinephrine, and 750-mg cefuroxime), and a placebo group (n=14), which received only saline solution. The primary outcome was a 10-point visual analog scale (VAS). Secondary outcomes were morphine consumption and cumulative ambulatory score (CAS), postoperative complications, and functional outcomes as a timed up-and-go (TUG) test and Harris hip score (HHS) at two, six, and 12 weeks postoperatively. Results The PMDI group demonstrated a significant reduction in the median VAS at the 48th hour postoperatively as compared to the placebo group (P = 0.019), and a non-significant reduction in the median VAS at the 36th and 60th hours (P = 0.058 and 0.110, respectively) and in a median dosage of morphine consumption on the second postoperative day (P = 0.140). There was no significant difference in postoperative ambulation and functional outcome between both groups (P > 0.05, all). Conclusion The PMDI regimen without NSAIDs is effective for postoperative analgesia on the second postoperative day in elderly FNFs undergoing BHA without any significant difference in functional outcome or postoperative complications.

Results following surgical resection of recurrent chordoma of the spine: experience in a single institution.

BACKGROUND: Chordoma of the spine is a low-grade malignant tumor with vague and indolent symptoms; thus, large tumor mass is encountered at the time of diagnosis in almost cases and makes it difficult for en-bloc free-margin resection. Salvage therapy for recurrent chordoma is very challenging due to its relentless nature and refractory to adjuvant therapies. The aim of this present study was to report the oncologic outcome following surgical resection of chordoma of the spine. MATERIALS AND METHODS: Retrospective review of 10 consecutive cases of recurrent chordoma patients who underwent surgical treatment between 2003 and 2018 at one tertiary-care center was conducted. RESULTS: There were 10 patients; 4 females and 6 males were included in this study. Eight patients had local recurrence. The recurrence was encountered at the muscle, surrounding soft tissue, and remaining bony structure. Distant metastases were found in 2 patients. The median time to recurrence or metastasis was 30 months after first surgery. CONCLUSION: En-bloc free-margin resection is mandatory to prevent recurrence. The clinical vigilance and investigation to identify tumor recurrent should be performed every 3 to 6 months, especially in the first 30 months and annually thereafter. Detection of recurrent in early stage with a small mass may be the best chance to perform an en-bloc margin-free resection to prevent further recurrence.

Usefulness of clinical predictors for preoperative screening of deep vein thrombosis in hip fractures.

BACKGROUND: Recent studies showed that preoperative deep vein thrombosis (DVT) was common after hip fracture (HF), and preoperative DVT screening has been recommended for preventing the fatal DVT-related complications, especially in elderly HF patients with high surgical risk. However, to our knowledge, no previous studies have demonstrated the correlation between the clinical risk predictors and preoperative DVT. Therefore, this study aimed to correlate those clinical predictors related to DVT risk assessment with the incidence of preoperative DVT. METHODS: A prospective study was conducted, between July 2015 and June 2016, in 92 HF patients. All patients were evaluated for the DVT-related risk, as patients' characteristics, clinical signs, D-dimer, DVT risk assessment score (Wells score and Caprini score), and then underwent doppler ultrasonography preoperatively. The incidence of preoperative DVT was correlated with each clinical risk predictor, and then significant factors were calculated for diagnostic accuracy. RESULTS: The average patients' age was 78 ± 10 years. Sixty-eight patients (74%) were female. The incidence of preoperative DVT was 16.3% (n = 15). The median time from injury to doppler ultrasonography was 2 days (range 0-150 days). DVT group showed a significantly higher in Wells score and Caprini score compared to the non-DVT group (p < 0.05 all). Sensitivity and specificity of Wells score ≥ 2 and Caprini score ≥12 were 47 and 81, and 93 and 35%, respectively. CONCLUSION: DVT risk assessment may be helpful for stratifying the risk of preoperative DVT in elderly HFs. Those with Caprini score ≥ 12 should be screened with doppler ultrasonography preoperatively. Those with Wells score 0-1 had low risk for preoperative DVT, so the surgery could perform without delay.

Predicting Factors for Allogeneic Blood Transfusion and Excessive Postoperative Blood Loss after Single Low-Dosage Intra-Articular Tranexamic Acid Application in Total Knee Replacement.

Background. Recently, intra-articular tranexamic acid (IA-TXA) application has become a popular method for perioperative blood loss (PBL) reduction in total knee replacement (TKR). Nevertheless, through our knowledge, no previous studies had shown the correlation perioperative factors and the risk of excessive PBL or need of blood transfusion (BT) after IA-TXA. Materials and Methods. A retrospective study was conducted in patients underwent 299 primary TKRs, using IA-TXA, during 2-year period (2013-2014). Patient's characteristic and perioperative data were reviewed and collected. PBL was measured as total hemoglobin loss (THL), estimated total blood loss (ETBL), and drainage volume per kg (DV/kg). Excessive PBL was defined as PBL that exceeded 90th percentile. Results. From multivariate analysis, low preoperative hemoglobin (Hb) level and body mass index (BMI) were the significant predictors of postoperative BT (p < 0.0001 and 0.003, resp.). Excessive THL significant associated with preoperative Hb (p < 0.0001). Excessive ETBL significantly associated with preoperative Hb, height, preoperative range-of-motion, and creatinine clearance (p < 0.05 all). Low BMI and large prosthesis size were the significant predictors of excessive DV/kg (p = 0.0001 and 0.002, resp.). Conclusions. Low preoperative Hb and BMI were the significant risks of postoperative transfusion after TKR with IA-TXA. Moreover, multiple perioperative factors could result in higher PBL.

Prevalence of High-Riding Vertebral Artery and Morphometry of C2 Pedicles Using a Novel Computed Tomography Reconstruction Technique.

STUDY DESIGN: Cross-sectional, matched-pair comparative study. PURPOSE: To determine whether a thin-sliced pedicular-oriented computed tomography (TPCT) scan reconstructed from an existing conventional computed tomography (CCT) scan is more accurate for identifying vertebral artery groove (VAG) anomalies than CCT. OVERVIEW OF LITERATURE: Posterior atlantoaxial transarticular screw fixation and C2 pedicle screws can cause vertebral artery (VA) injury. Two anatomic variations of VAG anomalies are associated with VA injury: a high-riding VA (HRVA) and a narrow pedicle of the C2 vertebra. CCT scan is a reliable method used to evaluate VAG anomalies; however, its accuracy level remains debatable. Literature comparing the prevalence of C2 VAG anomalies between CCT and TPCT is limited. METHODS: A total of 200 computed tomography scans of the upper cervical spine obtained between January 2008 and December 2011 were evaluated for C2 VAG anomalies (HRVA and narrow pedicular width) using CCT and TPCT. The prevalence of C2 VAG anomalies was compared using these two different measurement methods via a McNemar's test. RESULTS: Of the 200 patients studied, 23 HRVA (6.01%; 95% confidence interval [CI], 3.61%-8.39%) were detected with CCT, whereas 66 HRVA (16.54%; 95% CI, 12.85%-20.23%) were detected with TPCT (p<0.001). Sixty-two narrow pedicles (15.58%; 95% CI, 11.99%-19.15%) were detected with CCT, whereas 90 narrow pedicles (22.83%; 95% CI, 18.58%-26.87%) were detected with TPCT (p<0.001). CONCLUSIONS: VAG anomalies are commonly observed. A preoperative evaluation using TPCT reconstructed from an existing CCT revealed a significantly higher prevalence of C2 VAG anomalies than did CCT and showed comparable prevalence to previously published studies using more sophisticated and higher risk techniques. Therefore, we propose TPCT as an alternative preoperative evaluation for C2 screw placement and trajectory planning.

Anatomic Considerations of Intervertebral Disc Perspective in Lumbar Posterolateral Approach via Kambin's Triangle: Cadaveric Study.

STUDY DESIGN: Anatomical study. PURPOSE: To evaluate the anatomy of intervertebral disc (IVD) area in the triangular working zone of the lumbar spine based on cadaveric measurements. OVERVIEW OF LITERATURE: The posterolateral percutaneous approach to the lumbar spine has been widely used as a minimally invasive spinal surgery. However, to our knowledge, the actual perspective of disc boundaries and areas through posterolateral endoscopic approach are not well defined. METHODS: Ninety-six measurements for areas and dimensions of IVD in Kambin's triangle on bilateral sides of L1-S1 in 5 fresh human cadavers were studied. RESULTS: The trapezoidal IVD area (mean±standard deviation) for true working space was 63.65±14.70 mm2 at L1-2, 70.79±21.88 mm2 at L2-3, 99.03±15.83 mm2 at L3-4, 116.22±20.93 mm2 at L4-5, and 92.18±23.63 mm2 at L5-S1. The average dimension of calculated largest ellipsoidal cannula that could be placed in IVD area was 5.83×11.02 mm at L1-2, 6.97×10.78 mm at L2-3, 9.30×10.67 mm at L3-4, 8.84×13.15 mm at L4-5, and 6.61×14.07 mm at L5-S1. CONCLUSIONS: The trapezoidal perspective of working zone of IVD in Kambin's triangle is important and limited. This should be taken into consideration when developing the tools and instruments for posterolateral endoscopic lumbar spine surgery.

Demineralized Bone Matrix Add-On for Acceleration of Bone Healing in Atypical Subtrochanteric Femoral Fracture: A Consecutive Case-Control Study.

BACKGROUND: Delayed union and nonunion are common complications in atypical femoral fractures (AFFs) despite having good fracture fixation. Demineralized bone matrix (DBM) is a successfully proven method for enhancing fracture healing of the long bone fracture and nonunion and should be used in AFFs. This study aimed to compare the outcome after subtrochanteric AFFs (ST-AFFs) fixation with and without DBM. MATERIALS AND METHODS: A prospective study was conducted on 9 ST-AFFs patients using DBM (DBM group) during 2013-2014 and compared with a retrospective consecutive case series of ST-AFFs patients treated without DBM (2010-2012) (NDBM group, 9 patients). All patients were treated with the same standard guideline and followed up until fractures completely united. Postoperative outcomes were then compared. RESULTS: DBM group showed a significant shorter healing time than NDBM group (28.1 ± 14.4 versus 57.9 ± 36.8 weeks, p = 0.04). Delayed union was found in 4 patients (44%) in DBM group compared with 7 patients (78%) in NDBM group (p > 0.05). No statistical difference of nonunion was demonstrated between both groups (DBM = 1 and NDBM = 2, p > 0.05). Neither postoperative infection nor severe local tissue reaction was found. CONCLUSIONS: DBM is safe and effective for accelerating the fracture healing in ST-AFFx and possibly reduces nonunion after fracture fixation. Trial registration number is TCTR20151021001.