ABSTRACT
Introduction: Among operatively treated pediatric forearm fractures, many different fixation constructs are described. The goal of this study was to define the biomechanical properties of a double stacked 1/3 tubular plate construct used by the senior author for some fractures and to review available literature regarding the use of stacked plates. Methods: Biomechanical testing was performed by 4-point bending of three different plate constructs: 1/3 tubular plate, stacked 1/3 tubular plates, and 2.7 mm LC-DCP plate. Five test specimens were evaluated for each of the three plate constructs. From stress-strain curves, flexural stiffness (N/mm), force to cause plastic deformation (N), and force to cause 10° bend (N) were calculated and compared using standard t-test statistics. Results: Key outcome parameter means (± SD) for the three plate constructs (1/3 tubular plate, stacked 1/3 tubular plates, and 2.7 mm LC-DCP plate) were reported respectively as follows: flexural stiffness (55.4 ± 3.5 N/mm, 131.7 ± 3.5 N/mm, 113.3 ± 12.1 N/mm), force to cause plastic deformation (113.6 ± 11.0 N, 242.1 ± 13.0 N, 192.2 ± 17.9 N), and force to cause a 10° bend (140.0 ± 8.4 N, 299.4 ± 14.1 N, 265.5 ± 21.2 N). Mean values of all three measures were significantly larger for the stacked 1/3 tubular plates than for the other plate constructs. Conclusions: The stacked 1/3 tubular plate construct was biomechanically superior to the other plate constructs tested. Stacked plating significantly improved stiffness of the fracture fixation construct supporting the use of this technique in selected trauma cases.
ABSTRACT
STUDY DESIGN: Retrospective review of prospective data. OBJECTIVE: To delineate a curve threshold where further delay of surgery significantly increased the risks for patients with cerebral palsy (CP) scoliosis. SUMMARY OF BACKGROUND DATA: Two approaches exist in the management of CP scoliosis: a proactive one where surgery is recommended once there is a risk of progression (Cobb > 50°) and a reactive one where surgery is recommended after the patient/caregiver may have significant challenges caused by a large deformity. METHODS: A prospectively collected CP scoliosis surgical registry was queried for patients with minimum two years of follow-up. Three groups were delineated based on the distribution of curve magnitudes: <70° (proactive), 70°-90°, and >90° (reactive). Radiographic, surgical, and quality of life outcome data were compared between the groups using analysis of variance and chi-square analyses. RESULTS: There were 38 patients in the <70° group, 44 in the 70°-90° group, and 42 in the >90° group. They were similar in age. The >90° group had significantly longer operative time (p < .001), a higher percentage of anterior/posterior procedures (31% vs 5%), and a higher infection rate requiring I&D (16.7%) than the other groups (<70°: 5.3%; 70°-90°: 6.8%; p < .05). The percentage blood volume loss was significantly higher in the >90° group compared to <70°. There were no differences in length of hospitalization or intensive care unit stay. Preoperatively, the Caregiver Priorities and Child Health Index of Life with Disabilities (CPchild) QOL score was significantly higher for the <70° group. At two years, the <70° and 70°-90° groups reached similar QOL scores, whereas the >90° trended toward a lower postoperative QOL. CONCLUSIONS: Being proactive (Cobb <70°) has no advantage in terms of decreasing risks or improving outcomes compared to curves 70°-90°. However, delaying surgery to a curve greater than 90° increases the risk of infection, blood loss, and the need for anterior/posterior procedures. Ideally, surgery should be recommended for curves less than 90°.