Hallux valgus interphalangeus: reliability of radiological assessment.

Background: Reliable radiographic measurement of hallux valgus interphalangeus (HVI) deformity has a role in guiding surgical management. HVI can be assessed using: The aim of the study is to investigate the reliability of these radiological parameters.

Methods: Seventy foot radiographs in patients pre and post hallux valgus corrective surgery were assessed by 3 observers. HVI was assessed using the radiological measurements described above. Two-way random, single measure intra-class correlation coefficients were calculated to assess agreement.

Results: Inter-observer reliability showed good agreement for DASA [ICC=0.77(0.61-0.88)], and excellent for HIA [ICC=0.92(0.85-0.96)] and PDPA [ICC=0.91(0.84-0.96)]. Intra-observer reliability was excellent for all angles; DASA [ICC=0.88 (0.76-0.95)], HIA [ICC=0.94(0.86-0.97)] and PDPA [ICC=0.83(0.65-0.92)].

Conclusions: Reliability is good to excellent among these three radiological techniques for assessing HVI. The HIA and PDPA are slightly more reliable.