INTRODUCTION: The advent of pedicle screws which provide distraction and derotation has led to higher correction of major curves. Newer methods have been devised to evaluate preoperative coronal flexibility, including lateral-bending (LB), push-prone (PP) and fulcrum-bending (FB) radiographs. Documentation of a consistent radiographic method predictive of correction rate has not been established.

OBJECTIVE: To determine the most predictive radiographic method for evaluating spine flexibility and correction by comparing the correction rate (CR), flexibility rate (FR) and correction index (CI) of the Cobb's angle using the different radiographic methods.

METHODS: Preoperative radiographs of 20 patients who underwent spinal fusion for adolescent scoliosis were obtained using the LB, PP and FB method and compared with postoperative radiographs.

RESULTS: Comparing the mean Cobb angles using the different methods to that of postoperative standing showed that only the FB method is not significantly different from the latter (p=0.669). There was a significant difference between the Cobb's angle measured on the LB and PP and that measured on postoperative standing (p=0.043, p=0.008). Comparing the mean flexibility of the different methods with the mean CR also showed that the mean FR of LB (p=0.007) and PP (p=0.00013) were significantly different from the CR while that of FB is not significantly different from the CR (p=0.687).

CONCLUSION: The FB radiograph demonstrated no statistical difference compared to postoperative radiograph, FR, and CI.

Human ; Male ; Female ; Young Adult ; Adolescent ; Scoliosis ; Pedicle Screws ; Spinal Fusion ; Spine ; Radiography ; Posture ; Documentation

BACKGROUND: Studies comparing the relative strength of polymethylmethacrylate (PMMA) augmented fixation, standard plating and locked compression plate (LCP) system are few. The use of either the bone cement-augmented dynamic compression plate or the Hybrid LCP constructs may provide an additional tool for the treatment of fractures in patients with osteoporosis.

METHODS: Eighteen (18) osteoporotic cadaveric humeral bones were assigned randomly to each of three groups (Dynamic Compression Plate [DCP], DCP augmented with bone cement, and the Hybrid LCP system) and tested in anterior-posterior bending and torsion/external rotation. The load to failure values were obtained and the results for each specimen compared.

RESULTS: Significant differences were observed between the standard DCP and Hybrid LCP group (p-value=0.012), and in the cement-augmented and Hybrid LCP group (p-value=0.099) in torsion/external rotation loading. No significant difference was observed between the standard DCP and bone-cement augmented group (p-value=0.248). No significant difference was observed among the three groups in terms of stiffness (p-value=0.3868) in the four-point anterior-posterior bending modality. Screw pull-out of the implant was observed only in the regular DCP group in torsion/external rotation loading stress.

CONCLUSION: Significant differences were seen between the three constructs in torsion/external rotation but not in anterior-posterior four-point bending. Bone failure, but not screw pull-out, was seen in the Hybrid LCP and bone cement-augmented DCP groups in torsion. This study showed that the LCP system and the bone cement-augmented constructs may provide greater screw purchase to the osteoporotic humerus.

Human ; Humans ; Bone Cements ; Bone Screws ; Polymethyl Methacrylate ; Rotation ; Bone Plates ; Fracture Fixation, Internal ; Fractures, Bone ; Osteoporosis ; Humerus

OBJECTIVE: The main objective of this study was to evaluate clinical and radiographic outcomes of computer minimally invasive transforaminal lumbar interbody fusion (CNMIS TLIF). METHODS: Blood loss, operating time, complications, and hospital stay were identified through chart review. Numeric rating scale (NRS) scores for pain were taken during recent follow-ups, and these were compared to the pre-operative scores. Three different examiners assessed the pre-operative lumbosacral spine radiographs. At a 2-years follow-up, the patients were evaluated with NRS and the radiographs reassessed by three other examiners. RESULTS: Seventy-four patients with a mean age of 54 years underwent CNMIS TLIF. Average blood loss was 300 mL, operative time was 4.5 hours, and the average length of hospital stay was 8.5 days. A total of four complications were noted in our study. There was an improvement of mean local lordosis and regional lordosis. The paired-sample t-test showed that the anterior, middle, and posterior disc heights at the cage level were significantly increased compared to the pre-operative values. CONCLUSION: CNMIS TLIF is a safe and efficient method to achieve spinal fusion. There was a significant improvement in clinical outcomes in terms of pain relief. Radiologic parameters such as local lordosis, regional lordosis, and anterior, middle, and posterior disc heights showed significant improvements at 2-years follow-up.
Spinal Fusion ; Minimally Invasive Surgical Procedures ; Computers