Point vs. traditional method evaluation of hallux valgus: interreader reliability and intermethod performance using...

Area of Science:

• Orthopedics
• Radiology
• Podiatry

Background:

• Hallux valgus is commonly diagnosed using the hallux valgus angle (HVA) and intermetatarsal angle (IMA).
• Traditional measurement methods use midaxial lines, while a simpler point method has been proposed.
• Reliability and differences between these methods and imaging modalities (X-ray, MRI) require assessment.

Purpose of the Study:

• To compare the interreader reliability of traditional and point methods for measuring HVA and IMA.
• To assess intermodality agreement for these measurements between X-ray and MRI.
• To evaluate differences in angle magnitudes obtained by the two measurement methods.

Main Methods:

• 56 patients (18-100 years) with no history of foot trauma or hardware underwent X-ray and MRI.
• Two readers measured HVA and IMA using traditional midaxial and new point methods.
• Intraclass correlation coefficients (ICC) were calculated to assess reliability and agreement.

Main Results:

• Interreader reliability was high and similar for both methods for HVA (ICC 0.92-0.94) and IMA (ICC 0.76-0.77).
• Intermodality agreement was higher for HVA (ICC 0.85-0.88) than for IMA (ICC 0.58-0.74).
• Mean differences between methods were larger for the traditional method (HVA: 5.5°, IMA: 2.5°).

Conclusions:

• The hallux valgus angle (HVA) demonstrates higher reliability than the intermetatarsal angle (IMA) across both measurement methods and imaging modalities.
• A significant difference exists in the angle magnitudes obtained using the traditional versus the point method.
• The point method offers a reliable alternative for HVA and IMA assessment in hallux valgus diagnosis.