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STUDY DESIGN Quality improvement evaluation with retrospective analysis. OBJECTIVES To compare a technique to place pedicle screws (PS) using a novel detachable pedicle marker and probe (DPMP) and pulsed fluoroscopy (PF) vs. conventional technique utilizing PF with standard instruments (SI) and O-arm. Spinal fusion with pedicle screw instrumentation (PSI) is the mainstay in treatment of spinal deformities. Reports suggest that CT navigated (O-arm) PS placement is more accurate than fluoroscopy. However, these studies have not considered the increased radiation exposure associated with CT. METHODS Thirty-six patients with spinal deformity had PSI using PF and DPMPs. Accuracy of PS placement and radiation data from 14 dosimeters placed on the patient and around the operating room was analyzed. Results were compared to published data. RESULTS Mean fluoroscopic time was 13.4 s (range 6.0-32.4), and the mean cumulative dose was 3.1 mGy (range 0.2-16.4). learn more Median estimated effective dose to the patient was 0.22 mSv (range 0.0-0.7). The effective dose of radiation was reduced by 80% (0.22 mSv vs. 1.11 mSv) compared to low-dose O-arm. The surgical team did not receive any detectable radiation. The seconds of PF used to assist and confirm placement of PSs was reduced to 1.2 s/level compared to previous reports of 4.49 s/level using SIs. DPMPs reduced fluoroscopy to 0.84 s/PS compared to 7.36 s/PS using SIs to assist and confirm PS placement. PSs were accurately placed in 561 of 576 (97.4%), which is comparable to O-arm and fluoroscopy with SIs. CONCLUSIONS PS placement using PF and DPMPs to assist and confirm PS placement lowers radiation exposure to the patient and surgical team without compromising accuracy compared to O-arm and fluoroscopy with SIs. LEVEL OF EVIDENCE Therapeutic, Level IV (Retrospective case series, historical control).STUDY DESIGN Single center, retrospective chart review. OBJECTIVES To determine if routine posterior spinal fusion (PSF) is unnecessary in non-ambulatory growing rod graduates with SMA. Most non-ambulatory children with SMA develop early-onset scoliosis (EOS). Posterior growing rods (GR) have been shown safe and effective in managing spinal deformities in these children. The best management of these children, once graduated from their GR, is currently unknown. In this study, we report the clinical results of managing these children without routine definitive fusion following a course of GR treatment. METHODS A single-center, retrospective chart and radiographic review was performed on children with SMA treated with posterior distraction GR, with a two-year minimum follow-up since final lengthening. Electronic medical records and radiographs were reviewed for demographic variables, Cobb measurements, implant revisions, occult radiographic implant failure, symptomatic failure, and/or conversion to PSF. RESULT 12 patients (2 type 1, 9 type 2, 1 type 1/2) met inclusion criteria. Mean age at growing rod insertion was 6.2 years of age (range 4.1-8.2) and age at final lengthening 10.3 years of age (range 9.3-11.9). The mean time between last lengthening and latest clinical or radiographic review was 5.5 (range 2.1-9.0) years. Average mean pre, post, final Cobb angles were 71°, 27° (p  less then  0.001), 25°. Following final lengthening, only one patient required hardware revision and conversion to definitive fusion in attempts to alleviate chronic hip pain, which was unsuccessful. One additional patient was found to have an occult rod failure that has not required treatment. CONCLUSION While limited by sample size, this single-center cohort of non-ambulatory SMA patients with EOS treated with similar constructs suggests that routine, definitive fusion in SMA GR graduates may be unnecessary. LEVEL OF EVIDENCE Level IV.STUDY DESIGN A retrospective, comparative study. OBJECTIVE To compare the results, complications, and costs of preoperative halo-gravity traction in in- and outpatient settings. BACKGROUND DATA Surgical management of severe spinal deformities remains complex and controversial. Preoperative halo-gravity traction results in a decreased need for aggressive surgical techniques, lower incidence of intraoperative neurologic complications, and improvement of nutritional parameters and preoperative cardiopulmonary function. METHODS Twenty-nine patients younger than 18 years with kyphoscoliosis undergoing preoperative halo-gravity traction were divided into two groups inpatients (n 15) and outpatients (n 14, home care or care at the Foundation). Traction time (weeks), traction weight (kg), radiographic curve correction, complications, and costs were compared. For statistical analysis, t test and odds ratio were calculated with a significance of p  less then  0.05. RESULTS Mean traction time was 6 weeks for in- and 4 weeks for outpatients (p = 0.038). Initial traction weight was 6 kg in both groups, while final traction weight was 13 kg for in- and 15 kg for outpatients (p = 0.50). At the end of the traction period, coronal correction was 24° in in- and 28° in outpatients (p = 0.5), while sagittal correction was 27° and 29°, respectively (p = 0.80). Pin loosening was observed in 2 patients in each group, of whom 1 outpatient developed pin-site infection. In each group, one patient developed transient neurologic complications (odds ratio 1.091). Mean treatment cost per patient was 2.8-fold higher in inpatients. CONCLUSIONS Considering complications and costs, our results show that preoperative halo-gravity traction in an outpatient setting is an option to be taken into account. LEVEL OF EVIDENCE Grade III.STUDY DESIGN Biomechanical analysis of scoliosis instrumentation using superelastic Nickel-titanium shape memory (SNT) rods. OBJECTIVE To compare SNT with conventional Titanium (Ti) and Cobalt-chrome (Co-Cr) rods. A clinical trial has documented comparable efficacy between two adolescent idiopathic scoliosis (AIS) cohorts instrumented using SNT versus conventional Ti rods. The shape memory and superelasticity of the SNT rod are thought to allow easy rod insertion, progressive curve correction, and correction from spinal tissue relaxation, but study is yet to be done to assess the effects of the shape memory and superelasticity. METHODS Instrumentations of AIS patients from the clinical trial were computationally simulated using SNT, Ti and Co-Cr rods (5.5 or 6 mm; 30°, 50° or 60° sagittal contouring angles; 0°, 25° or 50° coronal over-contouring angles). Curve correction, its improvement from stress relaxation in the spine, and loads in the instrumentation constructs were computed and compared. RESULTS The simulated main thoracic Cobb angles (MT) and thoracic kyphosis with the SNT rods were 4°-7° higher and 1°-2° lower than the Ti and Co-Cr rods, respectively.