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OBJECTIVEThe aim of this study was to evaluate the anatomical and surgical risk factors for screw-related facet joint violation at the superior level in lumbar fusion.METHODSThe authors conducted a retrospective review of a consecutive series of posterior lumbar instrumented fusions performed by a single surgeon. Inclusion criteria were primary lumbar fusion of 1 or 2 levels for degenerative disorders. The following variables were analyzed as possible risk factors: surgical technique (percutaneous vs open screw placement), depth of surgical field, degree of anterior slippage of the superior level, pedicle and facet angle, and facet degeneration of the superior level. Postoperative CT scans were evaluated by 2 independent reviewers. Axial, sagittal, and coronal views were reviewed. Pedicle screws were graded as intra-articular if they clearly interposed between the superior and inferior facet joints of the superior level. Multivariate logistic regression analyses were conducted to assess the factors associated with this complication.RESULTSOne hundred thirty-one patients were included. Interobserver reliability for facet joint violation assessment was high (κ = 0.789). The incidence of superior facet joint violation was 12.59% per top-level screw (33 of 262 proximal screws). The rate of facet violation was 28.0% in the percutaneous technique group (14 of 50 patients) and 12.3% in the open surgery group (10 of 81 patients) (OR 2.26, 95% CI 1.09–4.21; p = 0.024). In multivariate logistic regression analysis, independent predictors of facet violation were percutaneous screw placement (adjusted OR 3.31, 95% CI 1.42–7.73; p = 0.006), right-side pedicle screw (adjusted OR 3.14, 95% CI 1.29–7.63; p = 0.011), and facet angle > 45° (adjusted OR 10.95, 95% CI 4.64–25.84; p < 0.0001).CONCLUSIONSThe incidence of facet joint violation was higher in percutaneous minimally invasive than in open technique for posterior lumbar spine surgery. Also, coronal orientation of the facet joint is a significant risk factor independent of the surgical technique.

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Metal-on-metal (MOM) bearing surfaces in total hip arthroplasty have been recently shown to have acceptable survivorship properties, and they have certain advantages and disadvantages when compared to conventional metal-on-polyethylene bearing surfaces. Like traditional metal-on-polyethylene bearings, these metal-on-metal implants may also suffer from catastrophic failure. Patients can develop a local reaction to the metal ions produced by the articulation and present with pain or early loosening due to the local inflammatory reaction. The possible effects of MOM wear debris and its corrosion products are still the subject of debate. This case report represents an unusual situation in a 63-year-old woman in which extensive lysis derived in massive femoral osteolysis and hip arthroplasty catastrophic failure.

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Asymptomatic children and adolescents tend to stand with a stable global balance, and 95 % have an SSA and ST between 116° and 149° and 85°-102°, respectively. C7 plumbline in front of the HA is not necessarily associated with a spinal pathology.

Purpose To develop an animal model of spine and chest wall deformity (CWD) at birth and to evaluate its effects on respiratory system mechanics and lung development. Methods A spine and CWD was created in utero between 70 and 75 days of gestation in six ovine fetuses by resection of the seventh and eighth left ribs. Two days after birth, respiratory system mechanics was assessed in anesthetized lambs using the flexiVent apparatus, followed by postmortem measurement of lung mechanics as well as histological lung analysis. Results A range of severity of CWD was found (Cobb angle from 0° to 48°) with a mean decrease in compliance of 47% and in inspiratory capacity of 39% compared to control lambs. Proof-of-concept histological analysis in one lamb showed marked lung hypoplasia. Conclusion Our ovine model represents a pilot proof-of-concept study evaluating the impact of a spine and CWD present at birth on lung respiratory mechanics and development. This study lays down the groundwork for future studies evaluating the impact of these deformities on lung development and potential treatments.Graphical abstract These slides can be retrieved under Electronic Supplementary Material.