The Effect of Prolonged Pre-Operative Halo Gravity Traction for Severe Spinal Deformities on the Cervical Spine Radiographs.

STUDY DESIGN: Retrospective review of consecutive series. OBJECTIVE: The study sought to assess the effect of prolonged pre-operative halo gravity traction (HGT) on the c-spine radiographs. METHODS: Data of 37 pediatric and adult patients who underwent ≥ 12wks pre-op HGT prior to definitive spine surgery from 2013-2015 at a single site in West Africa was reviewed. Radiographic assessment of the c-spine including ADI, SVA and C2-C7 Lordosis were done at pre HGT and at 4 weekly intervals. Paired T-Test was performed to evaluate changes in these parameters during HGT. RESULTS: 37pts, 18/19 (F/M). Average age 18.2yrs. Diagnoses: 22 idiopathic, 6 congenital, 3 Post TB, 2 NM and 4 NF. Average duration of HGT: 125 days. Baseline coronal Cobb:130 deg, corrected 30% in HGT; baseline sagittal Cobb:146 deg, corrected 32% post HGT. Baseline ADI (3.17 ± 0.63 mm) did not change at 4wks (P > 0.05) but reduced at 8wks (2.80 ± 0.56 mm) and 12wks (2.67 ± 0.51 mm) post HGT (P < 0.05). Baseline HGT SVA (20.7 ± 14.98 mm) significantly improved at 4wks (11.55 ± 10.26 mm), 8wks (7.54 ± 6.78 mm) and 12wks (8.88 ± 4.5 mm) (P < 0.05). Baseline C2-C7 lordosis (43 ± 20.1 deg) reduced at 4wks (26 ± 16.37 deg), 8wks (17.8 ± 14.77 deg) and 12wks (16.7 ± 11.33 deg) post HGT (P < 0.05). There was no incidence of atlanto-axial instability on flexion extension radiographs at any interval. CONCLUSION: Prolonged HGT, while providing partial correction of severe spine deformities, also appeared to have no adverse effect on atlanto-axial stability or cervical alignment. Therefore, HGT can be safely applied for several weeks in the preoperative management of severe spine deformities in pediatric/adult patients.

The Use of Halo Gravity Traction in the Treatment of Severe Early Onset Spinal Deformity.

STUDY DESIGN: Retrospective Review of Prospective cohort. OBJECTIVE: To describe the feasibility of preoperative halo gravity traction (HGT) with subsequent growing rod/guided growth (GR/GG) placement in early onset spinal deformity (EOSD). SUMMARY OF BACKGROUND DATA: In children with severe EOSD, primary implantation of GR/GG constructs is not always possible. We describe a staged protocol with preoperative HGT followed by GR/GG implantation. METHODS: EOSD patients treated with HGT prior to GR/GG implantation were included. HGT used traction up to 50% body weight for 4 to 29 weeks. Pulmonary function tests (PFTs) were performed before and after HGT. Coronal Cobb (CC) and Sagittal Cobb (SC) angles were measured on the Pre-HGT, Post-HGT and 6 week postop x-rays. RESULTS: Thirty patients were included. Average age at GR/GG implantation was 9 years. Most cases (n = 24, 80%) were idiopathic. Most pts had kyphoscoliosis (n = 16, 53.3%). Pre-HGT CC averaged 112 ±â€Š22° and SC averaged 106 ±â€Š26°. CC and SC improved 29% after HGT. There was a significant improvement in body mass index following HGT. CC improved further to 70 ±â€Š14° (36% vs. pre-HGT) and SC to 63 ±â€Š21° (41%) with GR/GG placement. HGT-related complications occurred in nine patients (30%); eight pin site infections, one cranial abscess. Most HGT complications were managed with local pin care and oral antibiotics. Halo revision was required in two pts (6.7%). There was no change in PFTs with HGT (P > 0.05). Averagely, 14 levels were spanned during GR/GG implantation; two patients required vertebral column resection. Surgical complications occurred in nine (30%) patients. At average 16 month follow-up, seven patients (23.3%) required reoperation. CONCLUSION: Preoperative HGT can make severe EOSD curves amenable to GR/GG implantation. HGT results in ∼30% correction with improvement to ∼35-40% following GR/GG. HGT has a 30% complication rate but most are pin-site infections managed with pin-site care and oral antibiotics; 6.7% of patients require revision. LEVEL OF EVIDENCE: 4.

Halo Gravity Traction Can Mitigate Preoperative Risk Factors and Early Surgical Complications in Complex Spine Deformity.

STUDY DESIGN: Retrospective review of prospective cohort. OBJECTIVE: We sought to examine the role of halo gravity traction (HGT) in reducing preoperative surgical risk. SUMMARY OF BACKGROUND DATA: The impact of HGT on procedure choice, preoperative risk factors, and surgical complications has not been previously described. METHODS: Patients treated with HGT before primary surgery were included. The FOCOS Score (FS) was used to quantify operative risk. FS was calculated using patient-factors (ASIA, body mass index, etiology), procedure-factors (PcF; osteotomy planned, number of levels fused, etc.), and curve magnitude (CM). Scores ranged from 0 to 100 with higher scores indicating increased risk. FS was calculated before and after HGT to see how changes in FS affected complication rates. RESULTS: A total of 96 patients were included. Halo-related complications occurred in 34% of patients but revision was required in only 8.3%. Average FS improved by 18 points after HGT. CM, PcF, and patient-factors all improved (P < 0.05). The greatest changes were in CM and PcF. The planned rate of three-column osteotomies dropped from 91% to 38% after HGT. FS (area under the curve [AUC]: 0.68, P = 0.023) and change in FS (AUC: 0.781, P < 0.001) was successfully able to predict the rate of surgical complications. A preoperative FS of 74 was identified as a cut-off for a higher rate of surgical complications (sensitivity 58.8%, specificity 74.7%). Patients with a reduction in FS <  = 10pts were five times more likely to have a complication (relative risk 5.2, 95% confidence interval: 1.9-14.6, P < 0.001). A multivariate regression showed that change in FS was an independent predictor of complication rates (P < 0.05). CONCLUSION: FS can successfully predict surgical risk in pediatric patients with complex spinal deformity. Preoperative HGT can reduce FS and surgical risk by improving CM, lowering three-column osteotomies use, and improving body mass index. A reduction in FS after HGT predicts a lower rate of surgical complications. LEVEL OF EVIDENCE: 3.

Apex of deformity for three-column osteotomy. Does it matter in the occurrence of complications?

BACKGROUND: Posterior vertebral column resection (PVCR) is a challenging but effective technique for the correction of complex spinal deformity. However, it has a high complication rate and carries a substantial risk for neurologic injury. PURPOSE: The aim was to test whether the apex of the deformity influences the clinical outcomes and complications in patients undergoing PVCR. STUDY DESIGN: A historical cohort was recruited from a single center and evaluated preoperatively, postoperatively, and at final follow-up. PATIENT SAMPLE: Ninety-eight hyperkyphotic patients undergoing PVCR were included. Inclusion criteria consisted of kyphoscoliosis and hyperkyphosis surgically treated with PVCR as a primary or revision procedure. OUTCOME MEASURES: The outcome measures included a number of neurologic complications. METHODS: Receiver operator characteristic (ROC) curve analysis and Youden index (J) were used to estimate the optimum cut-off to predict neurologic complications for each potential risk factor. In three ROC analyses, we included separately body mass index (BMI), kyphosis degree, and age as independent variables and neurologic complications as the dependent variable. Logistic regression was used to estimate the odds ratios (ORs) and construct 95% confidence intervals (CIs). RESULTS: Among the 98 patients, the etiologies were: post infectious (50), congenital (31), and others (17). The averages were: age 14±6.5 years, BMI 20±10 kg/m(2), American Society of Anesthesiologists 3±0.7, forced vital capacity 76±23%, fusion levels 10±3, estimated blood loss 1,319±720 mL, surgical time 375±101 minutes, and preoperative localized kyphosis 104±30°. Thirty-three patients had abnormal preoperative neurologic status. Major complications occurred in 46 patients (neurologic in 25). The apex of kyphosis was proximal thoracic T1-T5 (five patients), thoracic (TH) T6-T9 (17 patients), thoracolumbar T10-L2 (55 patients), and lumbar L3-S1 (nine patients). The level of apex and BMI were independent risk factors for neurologic complications: TH apex (OR: 101.30, 95% CI: 1.420-infinite; p=.037); BMI (OR: 1.92, 95% CI: 1.110-infinite; p=.026). CONCLUSIONS: Posterior vertebral column resection for severe spine deformity is technically demanding and carries a substantial risk. The apex is a variable that influences the occurrence of neurologic complications, and the presence of a TH apex in particular could be a preoperative risk factor for neurologic complications.

Preoperative halo-gravity traction for severe spinal deformities at an SRS-GOP site in West Africa: protocols, complications, and results.

STUDY DESIGN: Retrospective analysis of a prospectively collected single-center database. OBJECTIVE: We describe a modified halo-gravity traction (HGT) protocol for patients with severe spinal deformities in West Africa, and assess the clinical and radiographic outcomes. SUMMARY OF BACKGROUND DATA: Three-column osteotomies are frequently used in the correction of severe spinal deformities; however, these can be associated with high complication rates and significant risk for neurological injury. Preoperative traction is one modality used to obtain a partial correction prior to definitive fusion. Low numbers and variability of traction protocols, however, have limited previous reports of sustained HGT. METHODS: All patients who underwent HGT in Ghana from April 2012 to August 2013 were reviewed. HGT was started at 20% body weight and increased by 10% per week until 50% body weight was reached by 4 weeks or thereafter as tolerated. Demographic variables, operative data, radiographic parameters, and health-related quality of life scores were collected. A deformity reduction index was calculated at each time point by summing the scoliosis and abnormal kyphosis for each patient and reported as a percentage of the preoperative deformity. RESULTS: Twenty-nine patients underwent HGT for an average 107 days prior to definitive posterior spinal fusion (24 patients) or placement of growing rods (5 patients). The major curve improved from an average 131° to 90° (31%) after HGT, and to an average 57° (56%) postoperatively. Pure kyphotic curves were rigid (flexibility 22% after traction), with a correction index of 3.88, which is similar to historical controls. Deformity correction with HGT plateaued at 63 days. Overall Scoliosis Research Society-22 questionnaire scores improved significantly pretraction versus postoperatively, but there was no change after traction versus before traction. There were 11 pin tract infections, with no neurological complications. CONCLUSION: HGT is a safe method to partially correct severe spinal deformities prior to a definitive procedure, and may reduce the need for higher risk 3-column osteotomies. Importantly, kyphosis secondary to infection with spontaneous apical ankylosis is relatively resistant to HGT. LEVEL OF EVIDENCE: 4.