Objective assessment of plaster cast quality in pediatric distal forearm fractures: Is there an optimal index?

• Published in: Injury Vol. 48; no. 2; pp. 552 - 556
• Main Authors: Labronici, Pedro José, Ferreira, Leonardo Termis, dos Santos Filho, Fernando Claudino, Pires, Robinson Esteves Santos, Coitinho, Davi, da Silva, Luiz Henrique Penteado, Gameiro, Vinicius Schott
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.02.2017
• Subjects: Adolescent; Brazil; Casting indices; Casts, Surgical - adverse effects; Casts, Surgical - standards; Child; Child, Preschool; Clinical Competence - standards; Distal forearm fracture; Female; Forearm Injuries - diagnostic imaging; Forearm Injuries - physiopathology; Forearm Injuries - therapy; Fracture Healing; Humans; Male; Orthopedics; Patient Outcome Assessment; Pediatrics; Prognosis; Radiography; Radius Fractures - diagnostic imaging; Radius Fractures - therapy; Recurrence; Reproducibility of Results; Retrospective Studies; Ulna Fractures - diagnostic imaging; Ulna Fractures - therapy; Pediatrics; Prognosis; Casting indices; Distal forearm fracture
• DOI: 10.1016/j.injury.2016.12.007
• ISSN: 0020-1383

Abstract Background Several so-called casting indices are available for objective evaluation of plaster cast quality. The present study sought to investigate four of these indices (gap index, padding index, Canterbury index, and three-point index) as compared to a reference standard (cast index) for evaluation of plaster cast quality after closed reduction of pediatric displaced distal forearm fractures. Methods Forty-three radiographs from patients with displaced distal forearm fractures requiring manipulation were reviewed. Accuracy, sensitivity, specificity, false-positive probability, false-negative probability, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio were calculated for each of the tested indices. Results Comparison among indices revealed diagnostic agreement in only 4.7% of cases. The strongest correlation with the cast index was found for the gap index, with a Spearman correlation coefficient of 0.94. The gap index also displayed the best agreement with the cast index, with both indices yielding the same result in 79.1% of assessments. Conclusion When seeking to assess plaster cast quality, the cast index and gap index should be calculated; if both indices agree, a decision on quality can be made. If the cast and gap indices disagree, the padding index can be calculated as a tiebreaker, and the decision based on the most frequent of the three results. Calculation of the three-point index and Canterbury index appears unnecessary.