Predictive factors for intraoperative blood loss in surgery for adolescent idiopathic scoliosis.

BACKGROUND: Adolescent idiopathic scoliosis (AIS) is a common spinal deformity. Posterior spinal fusion remains an important surgical treatment for AIS. This study aims to determine the predictive factors for intraoperative blood loss in AIS surgery. METHODS: Patients who had undergone posterior spinal fusion for adolescent idiopathic scoliosis in a single university hospital were reviewed over a 7-year period. Predictive factors for intra-operative blood loss were studied by multivariate analysis to derive a regression model. Receiver operating characteristic analysis was performed to determine the cut-off values of factors contributing to significant intraoperative blood loss (≥500 ml). RESULTS: Two hundred and twelve patients were included. Intraoperative blood loss was found to be correlated with gender (rs = 0.30 (0.17-0.43)), preoperative hemoglobin level (rs = 0.20 (0.04-0.31)), preoperative Cobb angle (rs = 0.20 (0.02-0.29)), number of fused levels (rs = 0.46 (0.34-0.58)), operation duration (rs = 0.65 (0.54-0.75)), number of anchors (rs = 0.47 (0.35-0.59)), and p-value ranged from < 0.001 to < 0.05. Significant intraoperative blood loss was influenced by the male gender, operation duration greater than 257.5 min and more than 10 anchors used. CONCLUSIONS: Male gender, increased operation duration and higher number of anchors predicted higher intra-operative blood loss.

Fulcrum flexibility of the main curve predicts postoperative shoulder imbalance in selective thoracic fusion of adolescent idiopathic scoliosis.

PURPOSE: To identify preoperative predictors for postoperative shoulder imbalance (PSI) after corrective surgery of adolescent idiopathic scoliosis (AIS) and using the fulcrum-bending radiograph to assess flexibility. METHODS: A consecutive surgical cohort of AIS patients undergoing selective thoracic fusion with alternate-level pedicle screw fixation was prospectively studied. Preoperative anteroposterior, lateral and fulcrum-bending radiographs were analysed. Postoperatively, a minimum of 2 years clinical and imaging follow-up was performed of all patients. PSI was defined as a radiographic shoulder height difference of more than 20 mm. RESULTS: A total of 80 patients were included, and 14 patients (18%) were confirmed with PSI at final follow-up. The flexibility of MT curve was an independent risk factor for PSI (odds ratio (OR) = 3.3 per 10% decrease, 95% confidence interval (CI) 1.6-8.2). Twenty-seven patients had a preoperative MT flexibility of < 55% (OR = 11.5, 95% CI 2.8-46.2). Postoperative T1 tilt was significantly higher in the PSI group (p < 0.001), and a T1 tilt of more than 9° resulted in 7.2 times higher odds of developing PSI (95% CI 2.0-26.0). Fulcrum-bending correction index (FBCI) was significantly higher in the PSI group at final follow-up, and 25 patients had a final postoperative MT FBCI above 120% (OR = 8.5 (95% CI 2.3-31.0). CONCLUSIONS: A low preoperative curve flexibility is a significant predictor for PSI. The surgical strategy should consider proximal fusion in presence of low-flexibility MT curves and consider less aggressive MT curve correction. Achieving a level T1 should be a main priority during intraoperative correction and may require fusion of the PT curve. LEVEL OF EVIDENCE: III. These slides can be retrieved under Electronic Supplementary Material.

Laparoscopic Left Gastric Artery Aneurysm Resection.

Aneurysmal degeneration of the visceral branches of the abdominal aorta is a rare and potentially life-threatening disease entity. Visceral artery aneurysms (VAAs) are exceedingly rare and have a prevalence of 0.1 to 2%. The left gastric artery aneurysm (LGAA) is even more rare and accounts for less than 4% of all VAAs. There is scarce literature on treatment of LGAA by embolization; however, to date successful laparoscopic repair of an LGAA has not been described. We describe the successful treatment of an LGAA by laparoscopic ligation and resection in a 68-year-old male patient.

Antimicrobial prophylaxis to prevent surgical site infection in adolescent idiopathic scoliosis patients undergoing posterior spinal fusion: 2 doses versus antibiotics till drain removal.

PURPOSE: There is much variation in the choice, timing and duration of antimicrobial prophylaxis for preventing surgical site infections (SSI) but no guideline exists for scoliosis surgery. The aim of study was to compare the efficacy of two antimicrobial prophylaxis (AMP) protocols with cephazolin in preventing SSI in adolescent idiopathic scoliosis (AIS). METHODS: A retrospective comparative analysis of two post-operative AMP protocols (two postoperative doses versus continued antibiotics till drain removal) was performed. Patient characteristics, pre-operative, intra- and post-operative risk factors for infection, drain use, generic drug name and number of doses administered were recorded from 226 patients with AIS who had undergone posterior spinal fusion. Details of superficial or deep SSI and wound healing aberrations, and serious adverse events were recorded. Analysis was performed to evaluate differences in the pre-, intra- and post-operative variables between the two groups. RESULTS: 155 patients received 2 postoperative doses of AMP and 71 patients had antibiotics till drain removal. The average follow-up was 43 months. The overall rate of SSI was 1.7 % for the spine wound and 1.3 % for the iliac crest wound. 1.9 % of patients with 2 doses of AMP and 1.4 % of patients with antibiotics till drain removal had SSI. No adverse reactions attributable to cephazolin were observed. CONCLUSIONS: This is the first study on the AMP protocol in scoliosis surgery for SSI prevention. Results suggest that two doses of AMP are as effective as continued antimicrobial use until drain removal. Cephazolin appears to be effective and safe for prophylaxis.

Evaluating a Ward-based Foundation Year 1 (FY1) System in an Orthopaedic Setting.

BACKGROUND: Various models of hospital in-patient cover arrangements for junior doctors have been utilised in the United Kingdom. Some settings follow a team-based system for junior doctors and some a ward-based system. The aim of this study was to determine staff's satisfaction rates with regard to a ward-based system for Foundation Year 1 (FY1) doctors in relation to continuity of patient care and doctors' training. MATERIAL AND METHODS: The Orthopaedic department of a District Teaching Hospital in the United Kingdom moved to a ward-based system for the FY1s from a previous team-based system. A questionnaire was administered to FY1s, nursing staff and senior doctors asking their satisfaction rates. RESULTS: 42 practitioners were questioned. They included 15 FY1s, 15 ward nurses and 12 senior doctors. 73.3% of FY1s were satisfied with the ward-based system with regard to continuity of patient care and 40% of them were very satisfied/satisfied with it with regard to achieving training objectives. All nurses, 66.7% of FY1s and 66.7% of senior doctors were very satisfied/satisfied with the ward-based system for achieving service provision (p=0.053). All nurses and 60% of FY1s preferred the ward-based system (p=0.017). All nurses and 66.7% of senior doctors rated the ward-based system as being much better/better than team-based at achieving service provision (p-0.028). CONCLUSIONS: 1. Our results suggest that a ward-based system for FY1s can be successfully implemented in an orthopaedic setting. 2. Ward-based system confers high satisfaction rates with regard to care provision and continuity of care. 3. Taking into account training needs and substitutes for structured team work would be an area for improvement.

Thrombolysis for iliofemoral deep venous thrombosis.

Patients with iliofemoral deep vein thrombosis (DVT) comprise a subset of patients with DVT who are at significant risk for developing the postthrombotic syndrome (PTS) following treatment with anticoagulation alone. PTS can have debilitating effects on patients' quality of life. Its symptoms range from pain and heaviness to venous ulceration. Treatment techniques that eliminate the thrombus burden from the lower extremity have been shown to reduce the incidence of postthrombotic symptoms by restoring venous patency to the iliofemoral venous system and preserving valvular function. Treatment techniques include operative thrombectomy, catheter-directed thrombolysis and pharmacomechanical thrombolysis. This paper focuses on the latter two techniques and reviews the evidence for adopting the strategy of thrombus removal in patients with iliofemoral DVT.

Life-threatening postoperative hemorrhage from hepatic artery pseudoaneurysm successfully treated by transcatheter embolization in a 5-year-old.

Upper gastrointestinal bleeding caused by a pseudoaneurysm after hepatobiliary operation is well described in adults. This can be successfully treated with transcatheter embolization under angiographic guidance. We report a case of massive upper gastrointestinal bleeding in a 5-year-old boy secondary to a pseudoaneurysm of the right hepatic artery after choledochal cyst excision. A coil embolization successfully treated this life-threatening event and spared the child, the morbidity of a challenging gastrointestinal and vascular reconstruction. Use of percutaneous interventional technique to treat this rare complication of choledochal cyst excision has not been previously described in the pediatric surgical literature. Transcatheter embolization of a pseudoaneurysm may be a safe and less morbid treatment alternative for this surgical complication even in the pediatric population.

ISSLS prize winner: a study of effects of in vivo mechanical forces on human lumbar discs with scoliotic disc as a biological model: results from serial postcontrast diffusion studies, histopathology and biochemical analysis of twenty-one human lumbar scoliotic discs.

STUDY DESIGN: A comprehensive study of 21 lumbar scoliotic discs by in vivo serial post contrast diffusion magnetic resonance imaging (MRI), histopathological, and biochemical analysis. OBJECTIVE: To investigate the in vivo effects of compressive and tensile mechanical stress on the lumbar discs with scoliotic disc as the biologic model. SUMMARY OF BACKGROUND DATA: Most studies implicating mechanical stress in degenerative disc disease (DDD) are on animals, in vitro conditions and cadavers. They are also restricted to histopathological or biochemical evaluation without analyzing the endplate (EP) and nucleus pulposus (NP) separately. The few human studies have not analyzed diffusion changes which is the final pathway for DDD. Adolescent scoliotic disc offer a perfect model to study the effects of mechanical stress. METHODS: Twenty-one discs from 6 patients with adolescent idiopathic scoliosis undergoing anterior corrective surgery were assessed before surgery by postcontrast MRI to document the EP diffusion patterns. The same discs harvested during surgery were analyzed histologically and biochemically. The results were correlated to clinical and radiologic parameters. RESULTS: Altered diffusion patterns was seen in all discs with site specific breaks in 2, double peak pattern in 3, high intensity pattern in 14, and frank contrast leak in 2. There was marked decrease in cell density and viability in all discs on both convex and concave sides compared to the control disc (P = 0.001). Neovascularization, calcification, and matrix degeneration were observed to varying extent in different regions of NP and EP. There was a decrease in water content with increasing severity of curves with significant difference between mild and severe curves (NP: P = 0.000, EP: P = 0.002). Lactate was significantly higher in caudal EP (P = 0.035) and discs with coronal migration of more than 15 mm (P = 0.007). Regression analysis showed that truncal decompensation was a main factor for decrease in cell density, matrix degeneration, calcification, and water content. CONCLUSION: The study documents widespread changes in the EP and NP even in discs with minimal wedging. EP damage and alterations in diffusion were observed earlier than MRI changes and could indicate nutritional factors as the primary mechanism of degeneration induced by mechanical stress. Degeneration was more severe in caudal discs and those with truncal decompensation. Its implications on the timing and choice of surgery in scoliosis are discussed.

Iso-C3D navigation assisted pedicle screw placement in deformities of the cervical and thoracic spine.

BACKGROUND: Pedicle screw instrumentation of the deformed cervical and thoracic spine is challenging to even the most experienced surgeon and associated with increased incidence of screw misplacement. Iso-C3D based navigation has been reported to improve the accuracy of pedicle screw placement, however, there are very few studies assessing its efficacy in the presence of deformity. We conducted a study to evaluate the accuracy of Iso-C3D based navigation in pedicle screw fixation in the deformed cervical and thoracic spine. MATERIALS AND METHODS: We inserted 98 cervical pedicle screws (18 patients) and 242 thoracic pedicle screws (17 patients) using Iso-C3D based navigation for deformities of spine due to scoliosis, ankylosing spondylitis, post traumatic and degenerative disorders. Two independent observers determined and graded the accuracy of screw placement from postoperative computed tomography (CT) scans. RESULTS: Postoperative CT scans of the cervical spine showed 90.8% perfectly placed screws with 7 (7%) grade I pedicle breaches, 2 (2%) grade II pedicle breaches and one anterior cortex penetration (< 2mm). Five lateral pedicle breaches violated the vertebral artery foramen and three medial pedicle breaches penetrated the spinal canal; however, no patient had any neurovascular complications. In the thoracic spine there were 92.2% perfectly placed screws with only six (2%) grade II pedicle breaches, eight (3%) grade I pedicle breaches and five screws (2%) penetrating the anterior or lateral cortex. No neuro-vascular complications were encountered. CONCLUSION: Iso-C3D based navigation improves the accuracy of pedicle screw placement in deformities of the cervical and thoracic spine. The low incidence of pedicle breach implies increased safety for the patient.

Intraspinal anomalies in scoliosis: An MRI analysis of 177 consecutive scoliosis patients.

BACKGROUND: The association of intraspinal neural anomalies with scoliosis is known for more than six decades. However, there are no studies documenting the incidence of association of intraspinal anomalies in scoliotic patients in the Indian population. The guide lines to obtain an magnetic resonance imaging (MRI) scan to rule out neuro-axial abnormalities in presumed adolescent idiopathic scoliosis are also not clear. We conducted a prospective study (a) to document and analyze the incidence and types of intraspinal anomalies in different types of scoliosis in Indian patients. (b) to identify clinico-radiological 'indicators' that best predict the findings of neuro-axial abnormalities in patients with presumed adolescent idiopathic scoliosis, which will alert the physician to the possible presence of intraspinal anomalies and optimize the use of MRI in this sub group of patients. MATERIALS AND METHODS: The data from 177 consecutive scoliotic patients aged less than 21 years were analyzed. Patients were categorized into three groups; Group A - congenital scoliosis (n=60), group B -presumed idiopathic scoliosis (n=94) and group C - scoliosis secondary to neurofibromatosis, neuromuscular and connective tissue disorders (n=23). The presence and type of anomaly in the MRI was correlated to patient symptoms, clinical signs and curve characteristics. RESULTS: The incidence of intraspinal anomalies in congenital scoliosis was 35% (21/60), with tethered cord due to filum terminale being the commonest anomaly (10/21). Patients with multiple vertebral anomalies had the highest incidence (48%) of neural anomalies and isolated hemi vertebrae had none. In presumed 'idiopathic' scoliosis patients the incidence was higher (16%) than previously reported. Arnold Chiari-I malformation (AC-I) with syringomyelia was the most common neural anomaly (9/15) and the incidence was higher in the presence of neurological findings (100%), apical kyphosis (66.6%) and early onset scoliosis. Isolated lumbar curves had no anomalies. In group-C, incidence was 22% and most of the anomalies were in curves with connective tissue disorders. CONCLUSION: The high incidence of intraspinal anomalies in presumed idiopathic scoliosis in our study group emphasizes the need for detailed examination for subtle neurological signs that accompany neuro-axial anomalies. Preoperative MRI screening is recommended in patients with presumed 'idiopathic' scoliosis who present at young age, with neurological findings and in curves with apical thoracic kyphosis.