Effect of anterior mobilization and shortening in the correction of rigid idiopathic thoracic scoliosis.

STUDY DESIGN: Retrospective study of patients with anterior release and posterior correction instrumentation in a 2-stage procedure for rigid thoracic scoliosis. OBJECTIVE: To examine the effect of the anterior release and shortening alone as well as its role in the overall correction. SUMMARY OF BACKGROUND DATA: With segmental transpedicular instrumentation the need for an additional anterior mobilization became rare. However, its effect on sagittal profile was not sufficiently acknowledged. METHODS: Twenty-two patients with rigid thoracic scoliosis (Lenke 1A, n = 3; 2A, n = 6; 2B, n = 2; 2C, n = 1; 4B, n = 1; 4C, n = 9 patients) were operated in a 2-stage procedure with anterior release followed by posterior correction. The anterior release included convex resection of the rib heads and shortening of the anterior column by resection of the discs and the convex anterolateral endplates in a mean of 8 (4-11) segments.After 14 days (6-27), the posterior instrumentation and correction was done. RESULTS: The preoperative thoracic scoliosis measured a mean of 80°, upper thoracic 42°, and lumbar 49°. The thoracic curve corrected in bending 20° (25%), upper thoracic 10° (24%), and lumbar 26° (53%). The mean thoracic kyphosis (T5-T12) was 11°, lumbar lordosis was -41°.After the anterior release and shortening, thoracic scoliosis improved to 50°, thoracic kyphosis increased to 32°.After the posterior surgery the following values were noted: thoracic scoliosis 10°, upper thoracic 9°, lumbar 8°, thoracic kyphosis 25°, and lumbar lordosis -41°. The results were maintained at follow-up. CONCLUSION: Anterior shortening results in a spontaneous correction of the thoracic scoliosis and hypokyphosis. In this series, the Cobb angle reduced 38% from a mean of 80° to a mean of 50°. Thoracic kyphosis increased from 11° to 32°. This correction was achieved without any corrective force or instrumentation. The second-stage posterior correction is facilitated and nearly complete correction is achieved with a residual curve on average of 10° with a physiological sagittal profile. LEVEL OF EVIDENCE: 4.

Efficacy of hemivertebra resection for congenital scoliosis: a multicenter retrospective comparison of three surgical techniques.

STUDY DESIGN: Multicenter, retrospective study. OBJECTIVE: To compare the outcomes of three surgical treatments for congenital spinal deformity due to a hemivertebra. SUMMARY OF BACKGROUND DATA: Congenital anomalies of the spine can cause significant and progressive scoliosis and kyphosis. Their management may be challenging and controversy remains over the "best" surgical treatment. METHODS: A multicenter retrospective study of patients with congenital spinal deformity due to 1 or 2 level hemivertebra(e) was performed. The surgical treatments included hemiepiphysiodesis or in situ fusion (group 1), instrumented fusion without hemivertebra excision (group 2), or instrumented hemivertebra excision (group 3). RESULTS: Seventy-six patients with minimum 2-year follow-up were evaluated. The mean age was 8 years (range: 1-18). The hemivertebra were fully segmented, nonincarcerated (67%), incarcerated (1%), and semisegmented (32%). There were 65 patients with single hemivertebra and 11 patients with double hemivertebra. There were 14 (18.4%) group 1, 20 (26.3%) group 2, and 42 (55.3%) group 3 patients. Group 1 (37 ± 14°) and group 3 (35 ± 26°) patients had smaller preoperative curves than group 2 patients (55 ± 26°) (P < 0.01). Group 3 had better percent correction at 2 years than groups 1 and 2 (P < 0.001). Group 3 had shorter fusion (P = 0.001), less estimated blood loss (EBL, P = 0.03), and a trend toward shorter operative times than group 2 (P = 0.10). The overall complication rate for the entire group was 30% group 1 (23%), group 2 (17%), and group 3 (44%) (P = 0.09). CONCLUSION: While hemivertebra resection for congenital scoliosis had a higher complication rate than either hemiepiphysiodesis/in situ fusion or instrumentated fusion without resection, posterior hemivertebra resection in younger patients resulted in better percent correction than the other two techniques.

Infection rate after spine surgery in cerebral palsy is high and impairs results: multicenter analysis of risk factors and treatment.

UNLABELLED: Infection is a serious complication of surgery to correct scoliosis in patients with cerebral palsy (CP). We obtained multicenter representative figures for deep and superficial infection rates, analyzed risk factors and treatment outcomes, and compared deformity correction relative to infection. We retrospectively reviewed 157 patients who had posterior spinal fusion for CP at one of eight centers. Preoperative and intraoperative variables were subjected to multivariate analysis to determine factors predictive of infection. There were 16 wound infections (10%; nine deep, seven superficial). Only two study factors predicted infection: higher preoperative white blood cell count (8.5 versus 6.4 [in those without infection] x 10(3)) and use of a unit rod (15% versus 5% for bent rods). Fourteen patients underwent irrigation and débridement procedures. Five infections required 2 months or longer to resolve. Two had implant removal. Final curve correction was lower for those with deep infections than those without (67% versus 53%, respectively). We noted a trend toward greater percentages of pain at last followup in those with deep infection than in those without infection (50% versus 18%, respectively) but the study was not adequately powered to confirm this point. Our infection rate in scoliosis surgery for CP was higher than that for most elective spinal deformity surgery. LEVEL OF EVIDENCE: Level III, retrospective case-control study. See Guidelines for Authors for a complete description of levels of evidence.

Hemivertebra resection and osteotomies in congenital spine deformity.

STUDY DESIGN: Retrospective study of posterior hemivertebra resection and osteotomies with transpedicular instrumentation in very young children. OBJECTIVE: Assessment of early intervention in congenital scoliosis with almost complete correction of the main deformity. SUMMARY OF BACKGROUND DATA: There is a trend to early correction of congenital deformities, however, there is a lack of long-term follow-up. METHODS: Forty-one children aged 1 to 6 years with congenital scoliosis were operated on by hemivertebra resection by a posterior only approach with transpedicular instrumentation. Mean age at time of surgery was 3 years 5 months. They were retrospectively studied with a mean follow-up of 6 years 2 months. RESULTS: In group 1 (patients without bar formation), the average Cobb angle of the main curve was 36 degrees before surgery and 7 degrees after surgery. Compensatory cranial curve improved spontaneously from 15 degrees to 3 degrees, compensatory caudal curve from 17 degrees to 4 degrees. The angle of kyphosis was 22 degrees before surgery and 8 degrees after surgery. In group 2 (patients with bar formation) the main curve improved from 69 degrees to 23 degrees, cranial curve from 27 degrees to 11 degrees, caudal curve from 34 degrees to 14 degrees, and kyphosis from 24 degrees to 9 degrees. CONCLUSION: Posterior hemivertebra resection, in case of bar formation with osteotomy of the bar, allows for excellent correction in both the frontal and sagittal planes, with a short segment of fusion. Early surgery in young children prevents the development of severe local deformities and secondary structural curves, thus allowing for normal growth in the unaffected parts of the spine.

Scoliosis surgery in cerebral palsy: differences between unit rod and custom rods.

STUDY DESIGN: Retrospective review. OBJECTIVE: To evaluate the differences in intraoperative factors and postoperative results between pediatric patients with cerebral palsy (CP) treated with unit rods and those treated with custom-bent rods. SUMMARY OF BACKGROUND DATA: No prior study has directly compared unit and custom-bent rods for CP. METHODS: We retrospectively analyzed the clinical and radiographic data of 157 children with CP who underwent posterior spinal fusion. Of those 157, we treated 79 with unit rods and 78 with custom-bent rods. Minimum follow-up was 2 years. RESULTS: Intraoperatively, unit rod surgeries were associated with significantly shorter mean surgical time (339 and 379 minutes, respectively; P = 0.04), longer mean intensive care unit stay (4 vs. 3 days, respectively; P = 0.001), and longer mean hospital stay (14 vs. 13 days; P = 0.006) than custom-bent rod procedures. The mean estimated blood loss was higher for unit rods (2124 vs. 1885 mL, respectively), but not significantly so. After surgery, unit rod surgeries were associated with significantly more mean pelvic obliquity correction (74% vs. 22%, respectively; P = 0.002), more mean clinically apparent implant prominence at 2-year follow-up (12 vs. 2 instances; P = 0.03; most were proximal), and a higher mean infection rate (15% vs. 5%, respectively; P = 0.03). There were no significant differences in final major Cobb correction, curves with an apex above or below T10, implant-related reoperations, or neurologic complications. The only factor that was statistically correlated with the overall complication rate for both groups was absolute curve magnitude (P = 0.04). CONCLUSION: Compared with custom-bent rods, unit rods provided superior correction of pelvic obliquity but were associated with higher transfusion requirements, higher infection rates, more proximal fixation problems, and longer intensive care unit and hospital stays.

The use of traction in the treatment of severe spinal deformity.

STUDY DESIGN: Multicenter, retrospective, nonrandomized comparison group study of patients with severe scoliosis and kyphosis treated after 1995 with halo-gravity traction and without halo-gravity traction before definitive fusion. OBJECTIVE: Compare surgical correction of severe spine deformity with preoperative halo traction and without preoperative traction. SUMMARY OF BACKGROUND DATA: Prior studies have demonstrated that halo traction is a safe, well-tolerated method of applying gradual, sustained traction to maximize operative correction in patients with severe idiopathic scoliosis (IS) and kyphosis. However, these studies lack a comparison control group and study only a relatively small number of patients with IS. METHODS: Fifty-three patients with severe scoliosis or kyphosis were studied using hospital records, standing preoperative, traction, postoperative, and final radiographs. Thirty were treated with traction and 23 were treated without traction. Patients within each group were analyzed based on demographics, diagnosis, perioperative, and radiographic data. In addition, patients were evaluated based on diagnosis, specifically whether patients had adolescent idiopathic scoliosis. RESULTS: Within the entire study population, there was no statistically significant difference in main coronal curve correction (62% vs. 59%), operative time, blood loss, and total complication rate (27% vs. 52%). However, the nontraction group underwent vertebral column resection more often (30% vs. 3%, P = 0.015). The traction group had a statistically significant increase in average hospital stay (36 vs. 14 days) (P = 0.011). Analysis of the 23 patients with adolescent idiopathic scoliosis also showed no statistically significant differences in curve correction, blood loss, or complications. CONCLUSION: Our study shows that patients with halo traction less frequently had a vertebral body resection, but achieved comparable deformity correction.

Operative management of Scheuermann's kyphosis in 78 patients: radiographic outcomes, complications, and technique.

STUDY DESIGN: A retrospective multicenter review of 78 patients with Scheuermann's kyphosis treated operatively was conducted. OBJECTIVE: The purpose of this study was to evaluate correction of sagittal alignment, maintenance of correction, and occurrence of, and etiologic factors associated with, junctional kyphosis in patients managed operatively for Scheuermann's kyphosis. SUMMARY OF BACKGROUND DATA: There is a paucity of literature regarding the surgical treatment of Scheuermann's kyphosis using current implant systems and operative techniques. Junctional kyphosis has been shown to occur in up to one third of patients. Factors causing junctional kyphosis have not been clearly elucidated. Loss of correction has been variable based on the technique used. No clear-cut advantages or disadvantages have been shown for the use of anterior release. METHODS: Kyphosis, lordosis, C7 sagittal plumbline, apical translation, junctional sagittal alignment, and pelvic incidence were assessed among other radiographic parameters from a centralized database. The incidence of junctional kyphosis and its association to the above parameters and to fusion levels were assessed. Complication rates and differences between patients undergoing combined anteroposterior surgery and those having posterior surgery alone were evaluated. RESULTS: Of the 78 patients, 42 underwent combined anteroposterior procedures (Group 1) and 36 had posterior surgery only (Group 2). Mean age was 16.7 years. Overall, the greatest Cobb kyphosis of 78.8 degrees was corrected to 51.4 degrees at follow-up. Preoperative kyphosis was 82.6 degrees and 74.4 degrees for Groups 1 and 2, respectively (P < 0.001) and 55.8 degrees and 46.2 degrees at follow-up (P = 0.000). Loss of correction was 3.2 degrees (not significant) and 6.4 degrees (P = 0.000), respectively. Lordosis corrected from -65.5 degrees to -51.7 degrees . Proximal and distal junctional kyphosis of >or=10 degrees occurred in 25 (32.1%) and 4 (5.1%), respectively. The development of a proximal junctional kyphosis correlated directly with kyphosis at follow-up and indirectly with percent correction. Among patients with proximal junctional kyphosis, the magnitude of junctional kyphosis correlated directly with the degree of pelvic incidence. Pelvic incidence correlated directly with lumbar lordosis but not kyphosis. Twelve complications occurred in 12 patients, including posterior wound infection (1), distal (2), and proximal (1) junctional kyphosis, and pseudarthrosis (1), those requiring reoperation. CONCLUSION: This is one of the largest reported series of Scheuermann's kyphosis treated operatively to our knowledge. A high rate of junctional kyphosis, especially at the proximal end, is associated with surgery for Scheuermann's kyphosis using current techniques. Proximal junctional kyphosis is associated with higher magnitude of kyphosis at follow-up, less percent correction; its magnitude correlated directly with pelvic incidence. Loss of correction is less in patients undergoing combined anteroposterior surgery. Pelvic incidence correlates directly with lordosis but not kyphosis, suggesting that these parameters are not causative of Scheuermann's kyphosis.

Distal junctional kyphosis of adolescent idiopathic thoracic curves following anterior or posterior instrumented fusion: incidence, risk factors, and prevention.

STUDY DESIGN: This is a retrospective multicenter analysis of a subset of 375 patients with thoracic adolescent idiopathic scoliosis (AIS) treated with either anterior (238) or posterior (137) fusion with preoperative or postoperative distal junctional kyphosis (DJK) >or=10 degrees . OBJECTIVES: To determine the incidence of DJK before and after surgery in patients with AIS undergoing either anterior or posterior thoracic fusion, and provide recommendations for prevention. SUMMARY OF BACKGROUND DATA: DJK following surgical treatment for AIS may result in pain, imbalance, and unacceptable deformity. The true incidence of DJK following selective anterior or posterior instrumentation and fusion is unknown, as are "risk factors" for its development. METHODS: Mean age at surgery was 14.4 years (range 9.1-20.9) in the anterior group and 14.7 years (range 10.2-20.7) in the posterior. Analysis included the Cobb and instrumented levels of the thoracic curves, and sagittal measurements, all on preoperative and 2-year follow-up standing 36-in radiographs. RESULTS: In the anterior group, the incidence of preoperative DJK was 4.2%, and postoperative DJK was 7.1%. In the posterior group, the incidence of preoperative DJK was 5.0% and 14.6% after surgery. When postoperative DJK developed in the posterior group, mean postoperative T10-L2 was +17 degrees kyphosis compared to +2 degrees in the posterior group without DJK (P < 0.001). When postoperative DJK developed in the anterior group, mean postoperative T10-L2 was +12 degrees kyphosis compared to +2 degrees for the anterior group without DJK (P = 0.006). DJK was significantly more likely to occur in the posterior group if the Cobb was instrumented to less than Cobb +1 (P < 0.001). CONCLUSIONS: It appears that both posterior and anterior instrumentation for thoracic curves must include the junctional level to prevent postoperative DJK when postoperative DJK is present. The presence of increased kyphosis after surgery in the T10-L2 region seen in both anterior and posterior groups that had postoperative DJK develop constitutes a "risk factor" for the development of DJK.