Intraobserver and Interobserver Reliability of Three Classification Systems for Hallux Rigidus

Area of Science:

• Orthopedics
• Radiology
• Medical Imaging

Background:

• Multiple hallux rigidus classification systems exist, causing diagnostic and treatment inconsistencies.
• The reliability of these systems for hallux rigidus staging has not been previously evaluated.
• Standardized classification is crucial for consistent radiographic interpretation and patient management.

Purpose of the Study:

• To evaluate the intra- and interobserver reliability of three common hallux rigidus classification systems.
• To compare the reliability of the Regnauld, Roukis, and Hattrup and Johnson classifications.
• To determine if current systems provide consistent radiographic staging for hallux rigidus.

Main Methods:

• Ten foot and ankle surgeons reviewed 21 sets of plain radiographs.
• Surgeons classified each radiograph using the Regnauld, Roukis, and Hattrup and Johnson systems.
• Intraclass correlation coefficients were calculated to assess intra- and interrater reliability.

Main Results:

• Intrarater reliability was fair to good for Roukis (0.62) and Hattrup and Johnson (0.62) systems.
• Regnauld system showed borderline fair to good/poor intrarater reliability (0.43).
• All three systems achieved excellent interrater reliability for mean classifications.

Conclusions:

• Reliable classification systems are vital for hallux rigidus treatment and prognosis.
• The Roukis classification system exhibited the highest intrarater reliability in this study.
• All evaluated classification systems demonstrate acceptable reliability and reproducibility for hallux rigidus staging.