Jochen P. Son-Hing

Risk Factors for Major Complications After Surgery for Neuromuscular Scoliosis

Study Design. Retrospective, case series. Objective. To determine the prevalence of major complications and to identify factors that increase the risk of complications in patients undergoing surgery for neuromuscular scoliosis. Summary of Background Data. Complications after surgery for neuromuscular scoliosis are more prevalent than in idiopathic scoliosis. However, the associated risk factors have not been statistically significant. Methods. Our computerized Pediatric Orthopedic Spine Database identified 131 consecutive patients with neuromuscular scoliosis, excluding those with myelodysplasia, who underwent surgery and had a minimum of 2 years of follow-up. Preoperative, intraoperative, and postoperative factors were analyzed for any association with major complications and length of stay using stepwise logistic and multiple regression analyses. Odds ratios were calculated for significant dichotomous variables, and receiver operator characteristic curves were created for significant continuous variables. Results. There were 81 male and 50 female patients with a mean age at surgery of 13.4 years (range, 6–21 years). The majority of patients (n = 75) had cerebral palsy. Eighty-eight patients (67%) underwent posterior spinal fusion and segmental spinal instrumentation (only), whereas 43 patients (33%) underwent an anterior spinal fusion followed by a posterior spinal fusion with segmental spinal instrumentation. Seventy-seven patients (59%) were fused to the pelvis using the Galveston technique. The mean follow-up was 3.9 years (range, 2–16.9 years). There were 46 major complications in 37 patients (28% prevalence), including 2 deaths. Nonambulatory status (P < 0.05) and preoperative curve magnitude (P < 0.01) were associated with an increased prevalence of major complications. Nonambulatory patients (n = 94) were almost 4 times more likely to have a major complication (odds ratio of 3.8, P < 0.05) in comparison with ambulatory patients. A preoperative major curve magnitude of ≥60° (P < 0.01) was the most accurate indicator for an increased risk for a major complication. Conclusion. Nonambulatory status and a preoperative curve magnitude (≥60°) are directly associated with an increased risk for major complications and indirectly associated with increased length of stay. As such, we recommend operative intervention in neuromuscular scoliosis before curve progression to ≥60°. Level of Evidence. Level III.

Role of amicar in surgery for neuromuscular scoliosis

Study Design. A retrospective case-control study. Objective. Evaluate the effectiveness of Amicar in decreasing perioperative blood loss in patients with neuromuscular scoliosis undergoing posterior spinal fusion (PSF) and segmental spinal instrumentation (SSI). Summary of Background Data. Previously, a preliminary prospective; prospective randomized double-blind; same-day anterior and posterior spinal fusion; and fibrinogen studies have demonstrated Amicar to be effective in decreasing total perioperative blood loss and transfusion requirements in surgery for idiopathic scoliosis. Increased fibrinogen secretion is a possible explanation. We are now analyzing its effectiveness in neuromuscular scoliosis. Methods. Amicar was administered at 100 mg/kg over 15 minute not to exceed 5 g after anesthesia induction. Maintenance is 10 mg/kg/h until wound closure. There were 2 study groups: group 1 (n = 34), no Amicar and group 2 (n = 62) who received Amicar. The majority of patients in both groups had cerebral palsy. Total perioperative blood loss was determined from the estimated intraoperative blood loss and measured postoperative suction drainage. Total perioperative blood loss and transfusion requirements (cell saver and allogeneic) were compared using &khgr;2 or Fisher exact test. Results. There was statistically less estimated intraoperative blood loss, total perioperative blood loss, and transfusion requirements in group 2. Postoperative suction drainage was also less but did not reach statistical significance. In group 1, estimated intraoperative blood loss, measured postoperative suction drainage, and total perioperative blood loss were 2194 ± 1626 mL, 903 ± 547 mL, and 3055 ± 1852 mL, whereas in group 2, it was 1125 ± 715 mL, 695 ± 489 mL, and 1805 ± 940 mL. Transfusion requirements were 1548 ± 962 mL in group 1 but only 660 ± 589 mL in group 2 (P < 0.0001). Amicar was equally effective in all diagnoses. There were no complications related to the use of Amicar. Conclusion. Amicar was highly effective in decreasing perioperative blood loss and transfusion requirements in patients with neuromuscular scoliosis undergoing PSF and SSI. It was most effective in decreasing estimated intraoperative blood loss. This results in decreased transfusion requirements, costs, and potential transfusion-related complications.

Video-assisted thoracoscopic surgery in idiopathic scoliosis : Evaluation of the learning curve

Study Design. Retrospective review of patients with idiopathic scoliosis who underwent same-day or staged anterior and posterior spinal fusion and segmental spinal instrumentation. Objective. Evaluation of our learning curve with video-assisted thoracoscopic surgery (VATS) with respect to operative time, blood loss, and complications in patients with idiopathic scoliosis. Summary of Background Data. VATS is a minimally invasive alternative to thoracotomy in the management of idiopathic scoliosis. An increased or steep learning curve has been described in the initial application of this technique. Methods. We began performing VATS in 1998. We compared our first 25 consecutive VATS patients (Group 2) and subsequent 28 consecutive VATS patients (Group 3) to our previous 16 consecutive patients (Group 1) with a thoracotomy (1991–1998) for idiopathic scoliosis. Training at a sponsored regional course was obtained before performing our first VATS procedure. Results. VATS allowed more disc to be excised in Group 2 (4.5 ± 1, 5.7 ± 1, and 4.4 ± 1 discs in Group 1, Group 2, and Group 3, respectively) and significantly decreased the anterior operative time (215 ± 33, 260 ± 56, and 177 ± 47 minutes) and time per individual disc excision (50 ± 13, 47 ± 12, and 41 ± 12 minutes), while providing comparable correction of the thoracic deformity (67% ± 12%, 66% ± 10%, and 70% ± 13% correction). There was no increase in estimated intraoperative anterior blood loss (228 ± 213, 183 ± 136, and 211 ± 158 mL), estimated blood loss per disc excised (51 ± 42, 34 ± 29 and 48 ± 37 mL), or complications in the VATS groups. Complications were primarily pulmonary and resolved with medical therapy. Postoperative chest tube drainage (855 ± 397, 462 ± 249, and 561 ± 26l mL) and total perioperative anterior blood loss (1083 ± 507, 647 ± 309, and 773 ± 308 mL) were significantly decreased in the VATS groups, but this was attributed to the use of Amicar. Conclusions. VATS is an effective procedure for anterior spinal fusion in idiopathic scoliosis. The learning curve is short, provided appropriate training is obtained.

Comparison of supine bending, push-prone, and traction under general anesthesia radiographs in predicting curve flexibility and postoperative correction in adolescent idiopathic scoliosis.

Study Design. A prospective study comparing supine bending, push-prone, and traction under general anesthesia (UGA) radiographs in adolescent idiopathic scoliosis. Objective. To compare the effectiveness of 3 different flexibility methods on structural and nonstructural main thoracic (MT) and thoracolumbar/lumbar (TL/L) curves. Summary of Background Data. Supine side bending radiographs are the major method for determining curve reducibility. Push-prone radiographs show structural and compensatory curves on the same radiograph, but have not shown comparative reducibility in recent studies. Traction UGA is a relatively new modality which may offer similar or improved flexibility, while also showing structural and compensatory curves on the same radiograph. Methods. Fifty-eight patients with adolescent idiopathic scoliosis were prospectively studied with standing PA and lateral, supine bending and push-prone radiographs before surgery; traction UGA radiographs intraoperatively; and standing PA and lateral radiographs after surgery. Results. Traction UGA demonstrated equal flexibility to supine bending in structural MT and TL/L curves, with a trend towards more flexibility in severe MT curves ≥60°, while push-prone demonstrated significantly less flexibility. Each of the methods showed significantly less flexibility than postoperative correction in MT curves, while traction UGA and supine bending were not significantly different than postoperative correction in TL/L curves. Analysis of nonstructural TL/L curves showed that traction UGA and push-prone were not significantly different than postoperative correction, while supine bending overestimated postoperative correction. Conclusion. Traction UGA offers flexibility equivalent to supine bending for structural MT and TL/L curves, and flexibility comparable with push-prone for nonstructural TL/L curves. Traction UGA also shows both structural and compensatory curves on the same radiograph, and ultimately may provide a better estimate of spinal balance.

The role of Amicar in same-day anterior and posterior spinal fusion for idiopathic scoliosis.

Study Design. A retrospective study of the effectiveness of Amicar (epsilon aminocaproic acid). Objective. Evaluate the effectiveness of Amicar in decreasing perioperative blood loss and transfusion requirements in same-day anterior (ASF) and posterior spinal fusion (PSF) with segmental spinal instrumentation (SSI) for idiopathic scoliosis. Summary of Background Data. Preliminary prospective, prospective randomized double-blind, and fibrinogen studies have demonstrated Amicar to be effective in decreasing perioperative blood loss in patients with idiopathic scoliosis undergoing PSF with SSI. Increased fibrinogen secretion is a possible explanation. Methods. There were 73 consecutive patients divided into 3 study groups based on the administration of Amicar: Group 1 (n = 16), no Amicar; Group 2 (n = 18), Amicar for the PSF with SSI only; and Group 3 (n = 39), Amicar for both ASF and PSF with SSI. All patients were managed using the same general anesthesia technique, intraoperative procedure, postoperative care path, and indications for transfusion (hemoglobin <7g/dL). Total perioperative blood loss (estimated intraoperative blood loss for both procedures and measured postoperative chest tube and PSF wound suction drainage) and total transfusion requirements between groups were compared using one-way ANOVA. Results. There were statistically significant decreases in mean estimated intraoperative PSF with SSI, total perioperative blood loss, and transfusion requirements in the 2 Amicar groups. However, Amicar had no significant effect on estimated intraoperative ASF blood loss, chest tube drainage, or PSF wound suction drainage. Total perioperative blood loss and transfusion requirements (cell saver, autologous, directed, and allogeneic blood) were: 3442.8 ± 1344.0 mL and 1537.1 ± 905.1 mL in Group 1; 2089.8 ± 684.0 mL and 485.2 ± 349.8 mL in Group 2; and 2184.1 ± 1163.7 mL and 531.5 ± 510.5 mL in Group 3. There were no Amicar related complications. Conclusion. Amicar was highly effective in decreasing total perioperative blood loss and transfusion requirements in same-day ASF and PSF with SSI for idiopathic scoliosis. It results in less preoperative autologous blood donation, perioperative blood transfusion, costs, and potential transfusion-related complications. It was mosteffective in decreasing intraoperative estimated PSF with SSI blood loss. It had no significant effect during the ASF, postoperative chest tube, or PSF wound suction drainage. We now recommend that it be used for the PSF with SSI procedure only.

Intrathecal morphine for postoperative analgesia in patients with idiopathic scoliosis undergoing posterior spinal fusion.

Study Design. A retrospective study of postoperative pain management with intrathecal morphine. Objective. Identify the dosing regimen of intrathecal morphine that safely and effectively provides postoperative analgesia with minimal complications in patients with idiopathic scoliosis undergoing posterior spinal fusion (PSF) and segmental spinal instrumentation (SSI). Summary of Background Data. Postoperative pain after surgery for idiopathic scoliosis is a concern. Intrathecal morphine has been used to decrease pain. However, the most appropriate dose has not been determined. Methods. We retrospectively analyzed 407 consecutive patients with idiopathic scoliosis who underwent PSF and SSI at our institution from 1992 through 2006. Patients were divided into 3 groups based on the intrathecal morphine dose: no dose (n = 68); moderate dose of 9 to 19 &mgr;g/kg, mean 14 &mgr;g/kg (n = 293); and high dose of 20 &mgr;g/kg or greater, mean 24 &mgr;g/kg (n = 46). Data included demographics, Wong-Baker visual analog scale postoperative pain scores, postoperative intravenous morphine requirements, time to first rescue dose of intravenous morphine, and postoperative complications of pruritis, nausea/vomiting, respiratory depression, and pediatric intensive care unit (PICU) admission. Results. The demographics of the 3 study groups showed no statistical differences. The mean Wong-Baker visual analog scale pain score in the post anesthesia care unit was 5.2, 0.5, and 0.2, and the mean time to first morphine rescue was 6.6, 16.7, and 22.9 hours, respectively. In the first 48 postoperative hours, respiratory depression occurred in 1 (1.5%), 8 (2.7%), and 7 (15.2%) patients, whereas PICU admission occurred in 0 (0%), 6 (2%), and 8 (17.4%) patients, respectively. The majority of PICU admissions were the result of respiratory depression. Frequency of pruritis and nausea/vomiting was similar in all 3 groups. Conclusion. Intrathecal morphine in the moderate dose range of 9 to 19 &mgr;g/kg (mean 14 &mgr;g/kg), provides safe and effective postoperative analgesia in the immediate postoperative period for patients with idiopathic scoliosis undergoing PSF and SSI. Higher doses did not result in significantly better analgesia and had a greater frequency of respiratory depression requiring PICU admission.

Fusion Rates After Thoracoscopic Release and Bone Graft Substitutes in Idiopathic Scoliosis

Study Design. A retrospective assessment of fusion rates using either morselized allograft bone or demineralized bone matrix (DBM) following video-assisted thoracoscopic surgery (VATS) in idiopathic scoliosis. Objective. To compare fusion rates between allograft bone and demineralized bone matrix (Grafton DBM Flex) following VATS using on standard standing lateral spine radiographs. Summary of Background Data. Both VATS and bone graft substitutes are accepted surgical techniques. However, their concomitant use in spinal deformity surgery has not been previously reported. Bone graft substitute has the advantage of decreasing operative time, blood loss, and donor site morbidity associated with autografts. Methods. Anterior thoracic discectomies were performed using VATS. Forty patients with 1 year or more follow-up were evaluated—12 with morselized allograft bone (Allograft group) and 28 with folded Grafton DBM Flex (DBM group). Factors analyzed included age, number of anterior levels fused, operative time, anterior perioperative blood loss, curve correction, and fusion rates. Clinical and radiographic evaluations were performed before surgery and at month, 1 year, and at most recent follow-up. Interbody fusion was assessed on standing lateral radiographs using the Newton et al 4-level grading scale. Results. There were no significant differences in age at surgery, number of anterior vertebral levels fused, anterior operative time per level, anterior intraoperative blood loss, chest tube drainage and duration, or total perioperative anterior blood loss between the 2 groups. Percent curve correction from before surgery to the most recent follow-up were very similar in both Allograft (68%) and DBM groups (67%). At most recent assessment, 60 of 73 disc spaces (82%) in the Allograft group and 100 of 109 disc spaces (92%) in the DBM group were rated as radiographically fused (Newton et al Grade I and II). There was no significant difference between the 2 groups (P = 0.088). No patients were observed to have crankshaft, pseudoarthrosis or hardware failure. There were no complications related to the bone graft material used. Conclusion. Demineralized bone matrix (Grafton DBM Flex) seem to be an effective bone graft substitute in thoracoscopic surgery for idiopathic scoliosis.

Early onset scoliosis: the value of serial risser casts.

Background: Treatment of early onset scoliosis (EOS) is challenging. In many cases, bracing will not be effective and growing rod surgery may be inappropriate. Serial, Risser casts may be an effective intermediate method of treatment. Methods: We studied 20 consecutive patients with EOS who received serial Risser casts under general anesthesia between 1999 and 2011. Analyses included diagnosis, sex, age at initial cast application, major curve severity, initial curve correction, curve magnitude at the time of treatment change or latest follow-up for those still in casts, number of casts per patient, the type of subsequent treatment, and any complications. Results: There were 8 patients with idiopathic scoliosis, 6 patients with neuromuscular scoliosis, 5 patients with syndromic scoliosis, and 1 patient with skeletal dysplasia. Fifteen patients were female and 5 were male. The mean age at first cast was 3.8±2.3 years (range, 1 to 8 y), and the mean major curve magnitude was 74±18 degrees (range, 40 to 118 degrees). After initial cast application, the major curve measured 46±14 degrees (range, 25 to 79 degrees). At treatment change or latest follow-up for those still in casts, the major curve measured 53±24 degrees (range, 13 to 112 degrees). The mean time in casts was 16.9±9.1 months (range, 4 to 35 mo). The mean number of casts per patient was 4.7±2.2 casts (range, 1 to 9 casts). At the time of this study, 7 patients had undergone growing rod surgery, 6 patients were still undergoing casting, 5 returned to bracing, and 2 have been lost to follow-up. Four patients had minor complications: 2 patients each with superficial skin irritation and cast intolerance. Conclusions: Serial Risser casting is a safe and effective intermediate treatment for EOS. It can stabilize relatively large curves in young children and allows the child to reach a more suitable age for other forms of treatment, such as growing rods. Level of Evidence: Level IV; case series.

Surgical hip dislocation for removal of intraarticular exostoses: report of two cases.

Exostoses or osteochondromas are the most common benign bone tumors in children. The proximal femur is affected in approximately 30% of individuals and may lead to growth disturbances, acetabular dysplasia, and possible subluxation. Intraarticular lesions may also occur but are rarer. We present 2 cases of intraarticular exostoses that were successfully treated by surgical dislocation of the hip and complete excision of the lesion. However, despite successful excision, both hips are still abnormal because of the long standing inherent growth disturbance and residual acetabular dysplasia and may still require further surgery.

Bipolar sealer device reduces blood loss and transfusion requirements in posterior spinal fusion for adolescent idiopathic scoliosis.

Background: Reducing perioperative blood loss and transfusion requirements is important in the operative treatment of idiopathic scoliosis. This can be achieved with special frames, cell saver systems, pharmacologic aspects, and other techniques. Recently there has been interest in bipolar sealer devices as an adjunct to traditional monopolar electrocautery. However, there is limited information on this device in pediatric spinal deformity surgery. We reviewed our experience with this device in a setting of a standard institutional operative carepath. Methods: Perioperative blood loss and transfusion requirements of 50 consecutive patients with adolescent idiopathic scoliosis undergoing a posterior spinal fusion and segmental spinal instrumentation and who had a bipolar sealer device used during their surgery was compared with a control group of the 50 preceding consecutive patients who did not. Anesthesia, surgical technique, use of intraoperative epsilon aminocaproic acid (Amicar), postoperative protocol, and indications for transfusions (hemoglobin⩽7.0 g/dL) were identical in both groups. Results: The preoperative demographics for the patients in both groups were statistically the same. The bipolar sealer group demonstrated a significant reduction in intraoperative estimated blood loss, total perioperative blood loss, volume of blood products transfused, and overall transfusion rate when compared with the control group. When subgroups consisting of only hybrid or all-pedicle screw constructs were considered individually, these findings remained consistent. There were no complications associated with the use of this device. Conclusions: Using the bipolar sealer device is a significant adjunct in decreasing perioperative blood loss and transfusion requirements in patients undergoing surgery for adolescent idiopathic scoliosis. Level of Evidence: Level III—retrospective comparative study.