Radiocarpal and midcarpal joint congruency after perilunate dislocations and fracture-dislocations: a cross-sectional study

The purpose of this study was to evaluate carpal joint contact patterns after perilunate injuries and potential associations between functional and radiographic outcomes. Twenty-two patients with a computed tomography (CT) scan at least 2 years postoperatively were reviewed (mean follow-up 15 years). Assessment of carpal degenerative changes was done using Kellgren-Lawrence grading and CT-derived joint space area, which was calculated as the total area with interbone distance less than 2 mm. Increased joint space area signified a greater area with joint space narrowing and cartilage loss. Fifteen patients had severe joint space narrowing at the scaphocapitate and capitolunate joints. Nine and seven patients had severe narrowing at the radiolunate and radioscaphoid joints, respectively. Degenerative changes did not follow a typical scapholunate advanced collapse pattern. Increased scaphocapitate joint space area was associated with worse Patient Rated Wrist Evaluation scores (<i>r</i> = -0.47, <i>p = </i>0.02) and visual analogue scale pain scores (<i>r</i> = -0.44, <i>p = </i>0.03). This study suggests that patients with more severe degenerative changes after perilunate injuries may have worse functional outcomes.<b>Level of evidence:</b> IV.