Radiographic evaluation of calcaneal fractures: to measure or not to measure.

Objective: The aim of this study was to correlate the functional outcome after treatment for displaced intra-articular calcaneal fracture with plain radiography.

Design: The design was a prognostic study of a retrospective cohort with concurrent follow-up.

Patients: A total of 33 patients with a unilateral calcaneal fracture and a minimum follow-up of 13 months participated. Patients filled in three disease-specific questionnaires, graded their satisfaction and the indication for an arthrodesis was noted. Standardised radiographs were made of the previously injured side and the normal (control) side. Different angles and distances were measured on these radiographs and compared with values described in the literature. The differences in values in angles and distances between the injured and uninjured (control) foot were correlated with the outcome of the questionnaires, and the indication for an arthrodesis.

Results: None of the angles correlated with the disease-specific outcome scores. Of the angles only the tibiotalar angle correlated with the VAS (r = 0.35, p = 0.045) and only the absolute foot height correlated with the indication for an arthrodesis (odds = 0.70, CI = 0.50-0.99).

Conclusion: In this study the radiographic evaluation correlated poorly with the final outcome. Measurements on plain radiographs seem not to be useful in determining outcome after intra-articular calcaneal fractures.