Does Conventional Radiography Overrepresent Joint Space Narrowing in Hallux Rigidus? A Comparative Study With Weightbearing CT Imaging
Ahmed Saleh, Vineel Mallavarapu, Nacime Salomao Barbachan Mansur, Aly M. Fayed, Cesar de Cesar NettoBackground:
Conventional weightbearing radiographs are the gold standard for grading hallux rigidus (HR), yet clinical symptoms often do not correlate with radiographic severity. This study compared 2-dimensional (2D) weightbearing radiographs with weightbearing computed tomography (WBCT) to evaluate if traditional imaging overrepresents joint degeneration.
Methods:
A retrospective study of 21 patients (13 males; average age 55.9 years) with HR was conducted. All patients had both weightbearing radiographs and WBCT. Two fellowship-trained orthopaedic surgeons measured the first metatarsophalangeal joint (first MTPJ) space, dorsal osteophyte height, and dorsal narrowing percentage. Inter-rater reliability was assessed using intraclass correlation coefficients (ICCs).
Results:
Joint space width was significantly larger on WBCT (1.9 ± 0.44 mm) compared to radiographs (0.92 ± 0.53 mm;
Conclusion:
WBCT demonstrated consistently larger joint-space measurements and less dorsal joint-space narrowing compared with conventional radiographs, along with substantially higher inter-rater reliability for joint space narrowing. These findings indicate a systematic measurement difference between modalities, with radiographs tending to overrepresent joint-space loss. This discrepancy may help explain why joint-preserving procedures such as cheilectomy can succeed even when radiographs appear advanced.
Level of Evidence:
Level III, retrospective comparative study.