Changes in sagittal balance and pre-existing junctional angle influence development of proximal junctional kyphosis in growth guidance systems for early-onset scoliosis.

PURPOSE: Proximal junctional kyphosis (PJK) has been reported to occur at a rate of about 30% in traditional growing rods (GR) and magnetically controlled growing rods (MCGR). Growth guidance systems (GGS) have non-rigid, gliding fixation along rods, which may mitigate PJK. There have been no studies done in shilla around PJK, hence this study aimed to assess the occurrence, risk factors, and timeline of PJK. METHODS: A prospective, multicenter database was queried for EOS patients who underwent surgery utilizing GGS. INCLUSION CRITERIA: < 10 years at index surgery and > 2 year follow-up. RESULTS: Sixty-five patients (thirty-six female) met inclusion criteria. Mean age at index surgery was 6.2 y/o (2-9); mean follow-up was 66 m. Most common etiologies were syndromic (n = 23). Mean thoracic kyphosis at pre-op was 41.8°, post-op was 35.5°, and final was 42.2°. Mean PJA at pre-op was 6.15°, post-op 1 was 4.2°, and final was 15.6°. Incidence of PJK at post-op was 35% and final was 43%. Pre-op sagittal balance and change in sagittal balance from pre-op to post-op were associated with post-op PJK (p = 0.05, 0.02). Change in spinal height from pre-op to post-op was associated with PJK at final (p = 0.04). Interestingly, increased PJA at pre-op was significantly associated with decreased PJK at post-op and final (p = 0.01, 0.03). CONCLUSION: PJK was identified in 43% of patients post-operatively after GGS for EOS. Pre-op PJA was negatively correlated with an increased incidence of PJK. Changes in sagittal balance, in either direction, was the strongest predictor for development of PJK post-operatively.

Operative Technique for Sacral Insufficiency Fractures Causing Spinopelvic Dissociation: A Case Report.

CASE: We present a case of a 54-year-old man with atraumatic, U-type sacral insufficiency and L5 compression fractures leading to spinopelvic dissociation, inability to ambulate, and bowel/bladder compromise. The patient underwent L3-4 percutaneous pedicle screw fixation with bilateral iliac bolts and percutaneous iliosacral screw fixation. Postoperatively, the patient had return of bowel/bladder function and independent ambulation at 2.5 years. CONCLUSION: Atraumatic spinopelvic dissociation is an underappreciated pathology in older patients. Here, we describe the result of our preferred treatment strategy, triangular osteosynthesis, to preserve function and independence. Despite optimal, prompt treatment, these injuries pose a difficult rehabilitation process for patients.

Positive security screening episodes of patients with spinal implants are influenced by detector type and not implant material.

BACKGROUND CONTEXT: Previous research on rates of spinal detection showed a low frequency of patients (5%) experienced delays and additional screening going through airport security. With continuous technology advances in screenings and the rise in cobalt chrome implantation, updated data on patient experiences was needed. PURPOSE: 1) Assess the rates of detection and additional screening by traditional metal detectors and full body scanners in patients with metal spinal implants, 2) Compare the rates of detection of various metal types (Titanium and cobalt-chrome, titanium only, and stainless steel) STUDY DESIGN: Retrospective PATIENT SAMPLE: All spine surgical follow-ups over survey period. OUTCOME MEASURES: Self-reported open questionnaire; frequency of airport screening, patients' feelings and attitudes towards screening. METHODS: Patients were surveyed in the outpatient setting on exposure to metal detectors (Traditional and full-body scanners) after spinal surgery with metallic implants at a single institution. A total of 182 patients were identified and consented. The medical records were reviewed for details on implant material and location. RESULTS: Mean age at surgery was 53 years (range=12-88) with a mean 5.9 levels fused (range 2-20). Mean time from surgery to survey was 34 months (range=2-351) and number of airport screenings was 5.8 (range=0-54). The most common implants were titanium/cobalt-chrome (Ti/CoCr) (n=96, 53%) and titanium only (n=72, 40%). Overall, 40% of patients reported a detector alert at an airport requiring processing delay and additional screening: 86% from full body scanners, 54% from traditional metal detectors, and 41% of patients reporting both. Full body scanners were more likely to detect implants compared to traditional metal detectors (OR 5.1, p<.0001). No significant difference in number of screenings between patients who set off detectors and patients who did not (p=.185). Twenty percent of patients reported trouble at non-airport locations with detectors due to their spinal implants, with 70% of these patients reporting additional manual screenings. There was no correlation between levels spanned by the construct and number of times detected by traditional metal detectors or full body scanners, and no significant difference between levels spanned by constructs, or construct locations, in patients who set off detectors and those who did not. There was no significant difference between Ti/CoCr vs. titanium or other constructs in positive screenings. Subanalysis of fusions <5 levels demonstrated Ti/CoCr implants did not have an impact on positive screenings vs. other metal types (OR 0.88, p=.756). Interestingly, there was a significant difference in age and the positive screenings (p=.0025). Patients 60+ years of age had statistically significant greater positive screening than patients 0 to 40 years and 41 to 60 years. This data raises the possibility the presence of total joint arthroplasties (Mean age of patients with arthroplasty 65.5 years, range 50-88) likely play a significant role in the frequency of positive screenings. CONCLUSIONS: 40% of patients had their spinal implants detected at airports and 20% reported detections at other non-airport locations. Full body scanners detect spinal implants more frequently compared to traditional metal detectors (86% vs. 54% of detections, respectively). There was no difference in rate of airport and non-airport detection in patients with cobalt chrome implants compared to other materials. The presence of total joint arthroplasties likely has a significant contribution to the detector alerts.

Analysis of 280 Magnetically Controlled Growing Rod Lengthenings Comparing External Remote Control Readouts and Radiographic Measurements: Impact of Patient and Deformity Factors.

BACKGROUND: This study aimed to assess the accuracy of the external remote control (ERC) digital readout to the radiographic measurement of magnetically controlled growing rod (MCGR) actuators undergoing lengthenings/expansions and to analyze the impact of patient and spinal deformity factors on the accuracy of the ERC digital readout. METHODS: Single-surgeon database at 2 tertiary-care pediatric hospitals identified early-onset scoliosis patients with MCGR constructs. There were 14 males and 16 females with a minimum of 2 lengthenings included in the analysis. ERC readouts at each lengthening were recorded. RESULTS: Sixty-six MCGR actuators were assessed in 30 patients which underwent 280 lengthenings (mean of 5.7 lengthenings). At individual lengthening sessions the ERC and radiographic measurements were correlated (r = 0.69, P<0.001). The summed radiographic measurements averaged 15% less than the summed ERC readouts (SD = 19%). The difference between the sum of radiographic measurements and ERCs was positively correlated with subsequent lengthenings (r = 0.94, P = 0.015). The accuracy of the ERC did not improve with increased grouped sessions (r = -0.54, P = 0.388) with no difference between the group with 2 and the group with ≥5 lengthenings (P = 0.670). In patients with dual rods, the difference was correlated between rods (r = 0.66, P<0.001) and the distraction of each rod was not significantly different from the other (P = 0.124). Patient weight correlated with the difference between the radiographs and ERC readouts (r = 0.27, P = 0.032). In patients with multiple grouped lengthenings, increased weight was positively correlated with an increase in measurement difference (mean r = 0.972). CONCLUSIONS: Summed radiographic measurements during lengthening sessions averaged 15% less than the summed ERC readouts. The accuracy of radiographic measurements did not increase when sessions were grouped together (2 vs. ≥5). There was no difference in the ERC accuracy over lengthening sessions early versus late. Patient weight, but not body mass index, was positively correlated with the discrepancy between the ERC and radiographic measures. LEVEL OF EVIDENCE: Level III.