Intrarater and Interrater Reliability of the Soong Classification for Distal Radius Volar Locking Plate Placement

Abstract

The Soong classification is a reliable tool, both interrater and intrarater, for assessing distal radius volar locking plate placement. The classification system remained reliable despite a randomly selected, consecutive series of images and physician observers of varying levels of training.

Intraoperative Fluoroscopy Versus Postoperative Radiographs in Assessing Distal Radius Volar Plate Position: Reliability of the Soong Classification

“…Lutsky et al 16 used fellowship-trained upper-extremity surgeons and found an interobserver intraclass correlation of 0.78. In contrast to the study by Creighton et al, 15 this study suggests that kappa values for interobserver reliability gradually increase for each year of training. The fluoroscopic interobserver reliability increased from 0.16 for PGY3 to 0.43 for PGY4, while the radiographic reliability did not demonstrate a significant increase until PGY4 (κ = 0.50) ( Table 3 ).…”

“…The use of postoperative radiographs to assess plate prominence, although demonstrated to be reliable, may not be as beneficial as intraoperative fluoroscopy because of the time at which the images are obtained. 15 , 16 Our study suggests that early postoperative radiographs contribute no significant information with respect to plate prominence in comparison to intraoperative fluoroscopy but may be beneficial when examining the loss of fixation. For fracture reduction and fixation, the value of early postoperative radiographs in the treatment of distal radius fracture fixation has been questioned, and some studies have demonstrated that these images do not change postoperative management.…”

“…Previous studies showed good reliability of the Soong classification system for distal radius volar locking plate fixation in radiographic imaging without examining fluoroscopic imaging. 15 , 16 Plate positioning and plate prominence are more often assessed during surgery with fluoroscopy as the standard intraoperative imaging modality. By demonstrating moderate intraobserver reliability of fluoroscopy for the Soong classification system and agreement with postoperative radiographs, this study demonstrates that fluoroscopy is a reliable imaging modality for the assessment of plate prominence.…”

“…The relationship between physician experience and reliability of the Soong classification has been explored in prior research. Creighton et al 15 demonstrated that the intraobserver reliabilities of 6 physician observers of postoperative radiographs for distal radius volar plate prominence did not correlate with experience, as the lowest value was recorded by the most experienced surgeon. Lutsky et al 16 used fellowship-trained upper-extremity surgeons and found an interobserver intraclass correlation of 0.78.…”

“…Although research has shown that the Soong classification system demonstrated good reliability in assessing the degree of plate prominence on plain radiographs, there are no studies to date examining the reliability of the Soong classification system when comparing intraoperative fluoroscopy with postoperative plain radiographs. 15 , 16 …”