Efficacy of perioperative halo-gravity traction for treatment of severe scoliosis (≥100°).

BACKGROUND: There have been no standardized surgical options for severe scoliotic curvatures ≥100°. Halo-gravity traction is a viable option for surgical treatment of severe scoliosis. The aim of this study was to evaluate the efficacy and safety of perioperative halo-gravity traction for scoliosis curves ≥100° with respect to radiographic outcomes and clinical complications. METHODS: A total of 21 scoliosis patients with ≥100° curves (average 118.7°; range 100°-158°) with a minimum 2-year follow-up (average 41.8 months; range 24.0-97.0 months) who underwent spinal instrumented fusion using perioperative halo-gravity traction were analyzed. Diagnoses were neuromuscular scoliosis (n = 10), idiopathic (n = 9), and congenital (n = 2). In all, 15 patients were treated by the anterior release procedure followed by final posterior fusion and 6 patients by posterior fusion alone. Six patients had only preoperative traction preceding posterior fusion alone, 6 patients only staged traction between anterior release and final posterior fusion, and 9 patients had both preoperative traction preceding anterior release and staged traction preceding final posterior fusion. The average overall traction period in all patients was 67 days (range 10-78 days). RESULTS: Radiographic outcomes demonstrated 51.3% correction of the major Cobb angle, 40 mm correction of apical vertebral translation, 76 mm increase of T1-S1 length, and 20.7% increase of space available for lungs at the ultimate follow-up (all comparisons P < 0.05). Preoperative traction demonstrated 27.5% correction of the major curve Cobb angle, 51.5 mm increase of T1-S1 length, 14.9% increase of space available for the lungs (all comparisons P < 0.05). Staged traction after anterior release demonstrated 37.2% correction of the major curve Cobb angle, 26.1 mm correction of apical vertebral translation, 56.5 mm increase of T1-S1 length, 14.2% increase of space available for the lungs (all comparisons P < 0.05). There were only two patients with a pin-site problem, and one required débridement. There were no neurological deficits or clinical complications. CONCLUSIONS: Scoliosis patients with ≥100° curves can be managed successfully by corrective fusion surgery concomitant with perioperative halo-gravity traction without significant complications.

A novel pedicle channel classification describing osseous anatomy: how many thoracic scoliotic pedicles have cancellous channels?

STUDY DESIGN: Prospective clinical series. OBJECTIVE: To determine how many thoracic scoliotic pedicles have cancellous versus cortical versus absent channels. SUMMARY OF BACKGROUND DATA: Although morphologic evaluations of thoracic pedicles have been well reported, the results do not practically reflect clinical findings during actual pedicle screw placement. We propose a novel pedicle channel classification describing the osseous anatomy encountered during pedicle probe insertion. METHODS: We noted 4 pedicle types in 53 consecutive scoliosis patients. Type A: pedicle probe smoothly inserted without difficulty; the morphology is described as a "Large Cancellous Channel." Type B: pedicle probe inserted snugly with increased force; described as a "Small Cancellous Channel." Type C: pedicle probe cannot be manually pushed but must be tapped with a mallet down the pedicle into the body; described as a "Cortical Channel." Type D: pedicle probe cannot locate a channel thus necessitating a "juxtapedicular" screw position; described as a "Slit/Absent Channel." The average age at time of surgery was 23.4 ± 16.7 years. Diagnoses included idiopathic scoliosis (n = 38) and syndromic scoliosis (n = 15). The average main thoracic Cobb angle was 73° ± 26°. Evaluation of pedicle morphology of the 4 types was also performed in 21 consecutive cases of adolescent idiopathic scoliosis using preoperative computed tomography images. RESULTS: A total of 1021 pedicles with screws placed were evaluated. The average percent per type was as follows: 61.0% type A; 29.2% type B, 6.8% type C, and 3.0% type D. On the convexity, 98.2% of pedicles were type A or B versus 81.5% on the concavity (P < 0.05). There were significant differences between adolescent versus adult idiopathic scoliosis (P = 0.007), and syndromic scoliosis versus adult idiopathic scoliosis (P = 0.017) regarding pedicle morphologic proportions. There was a significant tendency toward a decrease in the proportion of type A pedicles, an increase in the proportion of type B pedicles as the Cobb angle increased (P < 0.0001). Evaluation based on 312 thoracic pedicles in 21 consecutive adolescent idiopathic scoliosis patients using preoperative computed tomography axial images confirmed assumptions of the 4 pedicle types. CONCLUSION: We propose a classification for pedicle channels describing the osseous anatomy encountered during pedicle probe insertion. Based on the classification, surprisingly, we found during surgery that 90% of thoracic pedicles had a cancellous channel, whereas 7% had a cortical channel and only 3% had an absent channel.

Proximal junctional vertebral fracture in adults after spinal deformity surgery using pedicle screw constructs: analysis of morphological features.

STUDY DESIGN: A retrospective comparative study. OBJECTIVE: To investigate the morphologic features of proximal vertebral fractures in adults following spinal deformity surgery using segmental pedicle screw instrumentation. SUMMARY OF BACKGROUND DATA: Fractures above pedicle screw constructs are a clinical problem that warrants further investigation for prevention and treatment. METHODS: Ten adult patients (6 lumbar scoliosis, 4 degenerative sagittal imbalance) who underwent segmental spinal instrumented fusion were analyzed. Patients were divided into 2 groups according to the features of vertebral fracture: upper instrumented vertebral collapse + adjacent vertebral subluxation (SUB group: n = 5), and adjacent vertebral fracture (Fracture group: n = 5). RESULTS: Both groups demonstrated a high frequency of osteopenia and all patients in the SUB group had comorbidities before surgery. The SUB group demonstrated a shorter interval between initial surgery and the fracture (subluxation: 3 +/- 1.9 months; fracture: 33 +/- 25.3 months, P < 0.05), and hypokyphosis (T5-T12) in the thoracic region before surgery (SUB: 13 degrees +/- 6.4 degrees; fracture: 33 degrees +/- 15.6 degrees). Both groups demonstrated severe global sagittal imbalance (SUB: 151 +/- 62.8 mm; fracture: 94 +/- 102.2 mm), and hypolordosis (T12-S1) in the lumbar spine (SUB: -19 degrees +/- 24.4 degrees ; fracture: -33 degrees +/- 22.7 degrees) before surgery. Global sagittal imbalance in the SUB group was corrected to 8 +/- 17.4 mm immediately postoperative (P < 0.05), but increased to 64 +/- 19.9 mm after the junctional fractures (P < 0.05). The SUB group demonstrated a significantly higher wedging rate (SUB: 65% +/- 12.4%; fracture: 36% +/- 16.0%, P < 0.05) and greater local kyphosis (SUB: 42 degrees +/- 11.1 degrees; fracture: 17 degrees +/- 4.1 degrees, P < 0.05) after the fracture. Two of 5 patients in the SUB group demonstrated severe neurologic deficit from E to B after the fractures by a modified Frankel classification. CONCLUSION: Old age, osteopenia, preoperative comorbidities, and severe global sagittal imbalance were found to be frequent in patients with proximal junctional fracture. In addition, marked correction of sagittal malalignment might be considered as a risk factor of upper instrumented vertebra collapse followed by adjacent vertebral subluxation, which occurred in the first 6 months after corrective surgery with the potential for causing severe neurologic deficit because of the severe local kyphotic deformity.

Vertebral column resection for the treatment of severe spinal deformity.

UNLABELLED: The ability to treat severe pediatric and adult spinal deformities through an all-posterior vertebral column resection (VCR) has obviated the need for a circumferential approach in primary and revision surgery, but there is limited literature evaluating this new approach. Our purpose was therefore to provide further support of this technique. We reviewed 43 patients who underwent a posterior-only VCR using pedicle screws, anteriorly positioned cages, and intraoperative spinal cord monitoring between 2002 and 2006. Diagnoses included severe scoliosis, global kyphosis, angular kyphosis, or kyphoscoliosis. Forty (93%) procedures were performed at L1 or cephalad in the spinal cord (SC) territory. Seven patients (18%) lost intraoperative neurogenic monitoring evoked potentials (NMEPs) data during correction with data returning to baseline after prompt surgical intervention. All patients after surgery were at their baseline or showed improved SC function, whereas no one worsened. Two patients had nerve root palsies postoperatively, which resolved spontaneously at 6 months and 2 weeks. Spinal cord monitoring (specifically NMEP) is mandatory to prevent neurologic complications. Although technically challenging, a single-stage approach offers dramatic correction in both primary and revision surgery of severe spinal deformities. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Is spine deformity surgery in patients with spastic cerebral palsy truly beneficial?: a patient/parent evaluation.

STUDY DESIGN: Retrospective clinical outcome study. OBJECTIVE: To evaluate the clinical outcomes and satisfaction associated with the surgical treatment of neuromuscular spinal deformity secondary to cerebral palsy. SUMMARY OF BACKGROUND DATA: Controversy still exists regarding whether spinal deformity surgery is truly a beneficial surgery for patients with cerebral palsy (CP) since there is limited functional benefit and higher perioperative complications rates in this patient population. METHODS: Neuromuscular patient evaluation questionnaires were answered retrospectively by 84 patients/families of spastic CP patients undergoing spinal fusion. The average follow-up was 6.2 years (range: 2-16). The questionnaires were designed to assess expectation, cosmesis, function, patient care, quality of life, pulmonary function, pain, health status, self-image, and satisfaction. Questionnaire results, complications, and radiographic data were divided into "satisfied group" and "less satisfied group" and we analyzed reasons of satisfaction and dissatisfaction. RESULTS: The overall satisfaction rate was 92%. Ninety-three percent reported improvement with sitting balance, 94% with cosmesis, and 71% in patient's quality of life. Functional improvements seemed limited, but 8% to 40% of the patients still perceived the surgical results as improvement. The postoperative complication rate was 27%. The mean preoperative Cobb angle of the major curve was 88 degrees (range: 53 degrees-141 degrees), which corrected to 39 degrees (range: 5 degrees-88 degrees) after surgery. The less satisfied group had a significantly higher late complication rate, less correction of the major curve, greater residual major curve, and hyperlordosis of the lumbar spine after surgery. CONCLUSION: Despite the perioperative difficulties seen with CP patients, the majority of the patient/parents were satisfied with the results of the spinal deformity surgery. Functional improvements were limited but 8% to 40% of the patients still perceived the results as improved. The reason for less than optimal satisfaction appears to be due to less correction of the major curve, greater residual major Cobb angle, hyperlordosis of the lumbar spine after surgery, and late postoperative complications.

Comparison of radiographic outcomes for the treatment of scoliotic curves greater than 100 degrees: wires versus hooks versus screws.

STUDY DESIGN: A retrospective comparative study. OBJECTIVE: To compare the efficacy and safety of several different anchors in the apical levels of scoliotic curves > or = 100 degrees using radiographic outcomes and clinical complications. SUMMARY OF BACKGROUND DATA: To the best of our knowledge, no reports have compared various anchors at the apical level for correction of scoliosis curves > or = 100 degrees. METHODS: Sixty-eight scoliosis patients (44 neuromuscular, 21 idiopathic, and 3 congenital) with major curves > or = 100 degrees (mean, 112.7 degrees; range, 100 degrees -159 degrees ) who underwent segmental spinal instrumentation and fusion with different anchors in the apical level were analyzed. All patients had a minimum 2-year follow-up (mean, 4.0 years; range, 2.0-10.5) and were divided into Group W (sublaminar wires n = 26), Group H (hooks n = 18), Group A (anterior vertebral screws n = 7), and Group PS (pedicle screws n = 17) based on the type of apical anchor used. Radiographic parameters and complications were investigated. RESULTS: The 4 groups did not demonstrate any significant differences in gender, age at surgery, preoperative major Cobb angle, or curve flexibility (all P > 0.05). However, the PS group demonstrated a shorter follow-up period compared with the other 3 groups (P < 0.05). The PS group demonstrated the greatest correction rate, smallest loss of correction (P < 0.05), and greatest amount of correction of the apical vertebral translation (P < 0.0005) at ultimate follow-up. There were 4 cases (5.9%) of pseudarthrosis (3 in Group W, 1 in Group H; P > 0.05), 6 cases (8.8%) of implant failure (4 in Group W, 2 in Group H; P > 0.05). Despite one (1.5%) intraoperative neurologic complication (differences among groups, P > 0.05), there was no permanent neurologic deficit. CONCLUSION: All 4 constructs were able to achieve and maintain acceptable correction safely without permanent neurologic deficit and all demonstrated acceptable implant failure rate. Pedicle screw constructs in the apical levels demonstrated the best coronal correction, smallest loss of correction, and greatest amount of apical vertebral translation correction of the major Cobb angle compared with the other constructs without neurologic complications.

Loss of spinal cord monitoring signals in children during thoracic kyphosis correction with spinal osteotomy: why does it occur and what should you do?

STUDY DESIGN: A retrospective review of pediatric kyphosis patients undergoing a spinal cord-level osteotomy for correction. OBJECTIVE: To evaluate the prevalence, etiology, timing, and intervention related to loss of spinal cord monitoring data during surgical correction of pediatric kyphosis in the spinal cord region. SUMMARY OF BACKGROUND DATA: Although much has been written regarding the risks inherent to scoliosis surgery, there is less literature available regarding the neurologic outcomes of pediatric kyphosis surgery. As more surgeons contemplate posterior-only kyphosis correction with spinal cord-level osteotomies, the importance of maintaining spinal cord neurologic function is paramount. METHODS: Forty-two patients with pediatric kyphosis undergoing a posterior-only spinal reconstruction with a spinal cord level osteotomy or posterior-based vertebral column resection performed were reviewed. Patients were categorized by diagnosis, type and incidence of osteotomies, and loss of neurogenic mixed-evoked potential (NMEP) data. Interventions required to regain data and postoperative neurologic outcomes were also reviewed. RESULTS: Of the 42 patients, 9 (21.4%) demonstrated a complete loss of NMEP data sometime during surgery while concomitant somatosensory sensory-evoked potentials (SSEP) remained within acceptable limits of baseline values. All 9 patients had intraoperative intervention including: blood pressure elevation (n = 1), release of corrective forces (n = 2), blood pressure elevation and correction release (n = 3), malalignment/subluxation adjustment (n = 1), further bony decompression (n = 1), or restoration of anterior column height via a titanium cage along with further posterior decompression (n = 1). In all cases, SSEPs were unchanged and NMEPs returned varying from 8 to 20 minutes after loss, with all patients having a normal wake-up test intraoperatively and a normal neurologic examination after surgery. CONCLUSION: Intraoperative multimodality monitoring with some form of motor tract assessment is a fundamental component of kyphosis correction surgery in the spinal cord region in order to create a safer, optimal environment and to minimize neurologic deficit. The surgeon must be able to trust the information monitoring provides and act on it accordingly.

Cross-cultural comparison of the Scoliosis Research Society Outcomes Instrument between American and Japanese idiopathic scoliosis patients: are there differences?

STUDY DESIGN: A comparative study. OBJECTIVE: To report a preliminary evaluation of the Scoliosis Research Society Outcomes Instrument (SRS-24) and determine whether differences in baseline scores exist between American and Japanese patients with idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Because the SRS outcomes instrument was primarily introduced for the American population, baseline scores in the Japanese population might differ from the American population. A comparative study using the SRS instrument between American and Japanese patients with idiopathic scoliosis has not been reported. METHODS: Two comparable groups of 100 idiopathic scoliosis patients before spinal fusion were separated into American (A) and Japanese (J). There were no statistically significant differences between the groups for gender (A: 9 men/91 women vs. J: 13 men/87 women), age (A: 15.0 +/- 2.4 vs. J: 14.9 +/- 3.8), main curve location (A: 77 thoracic/23 lumbar, J: 76 thoracic/24 lumbar), main curve Cobb angle (A: 50.5 +/- 5.2 vs. J: 51.1 +/- 8.7), and thoracic kyphosis (A: 20.9 +/- 14.3 vs. J: 19.9 +/- 12.1) (P > 0.05, for all comparisons). Patients were evaluated using the first section of the SRS-24 which was divided into 4 domains: total pain, general self-image, general function, and activity. SRS-24 scores were statistical compared in individual domains and questions using the Mann-Whitney U test. RESULTS: American patients had significantly lower scores in pain (P < 0.0001, A: 3.7 +/- 0.8 vs. J: 4.3 +/- 0.4), function (P < 0.01, A: 3.9 +/- 0.6 vs. J: 4.2 +/- 0.5), and activity (P < 0.0001, A: 4.5 +/- 0.8 vs. J: 4.9 +/- 0.3) domains compared with Japanese patients. Japanese patients had significantly lower scores in the self-image (P < 0.0001, A: 4.0 +/- 0.7 vs. J: 3.5 +/- 0.5) domain. With regard to individual questions, there were significant differences in the scores between the 2 groups for all questions except 5 and 13 (P < 0.05, for all comparisons). CONCLUSION: SRS-24 scores in the Japanese idiopathic scoliosis population differed from that of the American population. Japanese patients had less back pain, a negative self-image regarding back deformity, higher general physical function, and daily activity. It is highly probable that patient's perceptions differ due to cultural differences, which affect SRS-24 scores so a cross-cultural comparison of the SRS instrument content is necessary in the future.

Wasting of preoperatively donated autologous blood in the surgical treatment of adolescent idiopathic scoliosis.

STUDY DESIGN: Retrospective, case-control. OBJECTIVE: Evaluate the utility of preoperative autologous blood donation (PABD) for surgical treatment of adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: Recent data have highlighted overuse of PABD in elective surgery; however, PABD is a major blood conservation strategy for AIS surgery. METHODS: Medical records of 123 patients treated for AIS between June 1995 and November 2004 were reviewed. Patients were divided into PABD (n = 104) and nondonors (NPABD; n = 19). RESULTS: No differences existed between PABD and NPABD for age, major curve size, or operative procedures. Average PABD preoperative hematocrit was lower than NPABD (37.8 vs. 40.2; P < 0.005). PABD patients were 9 times more likely to be transfused than NPABD, and 3 times more likely to be transfused for each unit donated. There was a 25% transfusion risk reduction for each percent preoperative hematocrit increase. Minimum one autologous unit was not transfused in 32 patients (31%). Twenty-nine PABD patients (28%) were transfused for hematocrit >30. Fifty-three PABD patients (51%) wasted at least one unit or were transfused for hematocrit >30. CONCLUSIONS: The majority of PABD patients (51%) wasted minimum one autologous unit or were transfused at a high hematocrit (>30). More precise PABD guidelines are needed to limit unnecessary transfusion and wasted resources.

Analysis of patients with nonambulatory neuromuscular scoliosis surgically treated to the pelvis with intraoperative halo-femoral traction.

STUDY DESIGN: Retrospective case-control study. OBJECTIVES: To compare patients treated with and without intraoperative halo-femoral traction to assess neuromuscular spinal deformity correction as well as the safety of the technique. SUMMARY OF BACKGROUND DATA: Optimal sitting balance can be achieved in nonambulatory neuromuscular patients with pelvic obliquity by maneuvering a Galveston-type rod or inserting screws into the iliac wings; however, this is often clinically challenging because of the small, soft bone-stock in the pelvis of these patients. METHODS: A total of 40 patients with nonambulatory neuromuscular scoliosis were treated surgically with a T2 or T3-sacrum instrumented posterior spinal fusion. There were 20 patients (12 who underwent posterior spinal fusion-alone and 8 anterior/posterior spinal fusion) who had intraoperative halo-femoral traction performed unilaterally on the high side iliac wing compared to a control group of 20 patients (15 who underwent posterior spinal fusion-alone and 5 anterior/posterior spinal fusion) operatively treated without halo-femoral traction. Each group had 14 patients with spastic (cerebral palsy) scoliosis, and 6 with flaccid (muscular dystrophy) scoliosis deformities. Minimum follow-up for all patients was 2 years (range 3-12). RESULTS: Preoperative lumbar scoliosis averaged 87 degrees (range 30 degrees-141 degrees) in the halo-femoral traction group and 67 degrees (range 28 degrees-108 degrees) in the control group (P = 0.012). Postoperative lumbar Cobb decreased to 35 degrees (range 15 degrees-60 degrees) in the halo-femoral traction group and 32 degrees (range 4 degrees-66 degrees) in the control group (P = 0.181). Preoperative pelvic obliquity averaged 26 degrees (range 8 degrees-47 degrees) in the halo-femoral traction group and 17 degrees (range 8 degrees-44 degrees) in the control group (P = 0.017); postoperative averaged 6 degrees (range 1 degrees-23 degrees) in the halo-femoral traction group and 7 degrees (range 0 degrees-27 degrees) in the control group. Average pelvic obliquity correction was 78% in the halo-femoral traction group and 52% in the control group (P = 0.001). There were no intraoperative or postoperative halo-femoral traction apparatus-related complications noted (pin cut-out, femoral fractures, pin-sight infections, etc.). CONCLUSIONS: Intraoperative use of halo-femoral traction during the surgical treatment of patients with nonambulatory neuromuscular scoliosis provided significantly improved lumbar curve and pelvic obliquity correction. Intraoperative halo-femoral traction had no associated perioperative complications.