Radiographic union score for hip substantially improves agreement between surgeons and radiologists

Abstract

BackgroundDespite the prominence of hip fractures in orthopedic trauma, the assessment of fracture healing using radiographs remains subjective. The variability in the assessment of fracture healing has important implications for both clinical research and patient care. With little existing literature regarding reliable consensus on hip fracture healing, this study was conducted to determine inter-rater reliability between orthopedic surgeons and radiologists on healing assessments using sequential radiographs in patients with hip fractures. Secondary objectives included evaluating a checklist designed to assess hip fracture healing and determining whether agreement improved when reviewers were aware of the timing of the x-rays in relation to the patients’ surgery.MethodsA panel of six reviewers (three orthopedic surgeons and three radiologists) independently assessed fracture healing using sequential radiographs from 100 patients with femoral neck fractures and 100 patients with intertrochanteric fractures. During their independent review they also completed a previously developed radiographic checklist (Radiographic Union Score for Hip (RUSH)). Inter and intra-rater reliability scores were calculated. Data from the current study was compared to the findings from a previously conducted study where the same reviewers, unaware of the timing of the x-rays, completed the RUSH score.ResultsThe agreement between surgeons and radiologists for fracture healing was moderate for “general impression of fracture healing” in both femoral neck (ICC = 0.60, 95% CI: 0.42-0.71) and intertrochanteric fractures (0.50, 95% CI: 0.33-0.62). Using a standardized checklist (RUSH), agreement was almost perfect in both femoral neck (ICC = 0.85, 95% CI: 0.82-0.87) and intertrochanteric fractures (0.88, 95% CI: 0.86-0.90). We also found a high degree of correlation between healing and the total RUSH score using a Receiver Operating Characteristic (ROC) analysis, there was an area under the curve of 0.993 for femoral neck cases and 0.989 for intertrochanteric cases. Agreement within the radiologist group and within the surgeon group did not significantly differ in our analyses. In all cases, radiographs in which the time from surgery was known resulted in higher agreement scores compared to those from the previous study in which reviewers were unaware of the time the radiograph was obtained.ConclusionsAgreement in hip fracture radiographic healing may be improved with the use of a standardized checklist and appears highly influenced by the timing of the radiograph. These findings should be considered when evaluating patient outcomes and in clinical studies involving patients with hip fractures. Future research initiatives are required to further evaluate the RUSH checklist.

The Radiographic Union Score for Hip (RUSH) Identifies Radiographic Nonunion of Femoral Neck Fractures

“…The Radiographic Union Score for Hip (RUSH) is a previously validated tool that improves fracture healing agreement between radiologists and orthopaedic surgeons by using a checklist-based scoring approach [1,2,5]. Using this tool to grade the healing of femoral neck fractures leads to better agreement with respect to radiographic healing and improved intra-and interobserver reliability [5].…”

Clinical Aspects of Fracture Healing: An Overview

“…Recently introduced is a radiographic union scale for tibial fractures (RUST), as well as the radiographic union scale for hip (RUSH), both of which have been shown to increase agreement in inter-observer reliability among both surgeons and radiologists [35][36][37][38]. RUST is based on callus formation on the anterior, posterior, medial, and lateral cortices seen on AP and lateral radiographs of the fracture.…”

“…However, further studies are required to fully validate the scoring system as there is currently no gold stand comparison for RUST. Similar to RUST, RUSH provides standardized radiographic criteria to assess for the degree of hip fracture healing based on the presence or absence of bridging callus and fracture line [37].…”

Fracture healing: a consensus report from the International Osteoporosis Foundation Fracture Working Group

“…In the evaluation of the X-rays, qualifications such as whether callus formation is visible and whether the fracture line is visible help to quantify the degree of fracture healing that has occurred at the fracture site. Scoring systems such as the radiographic union score for hip (RUSH) [50,51] and radiographic union score for tibia (RUST) [52] are based on cortical scores. It is from these scoring systems that the concept that only two cortices could be completely radiographically healed (and get a healed level score) and yet the other two cortices could still show fracture lines and some or no callus.…”