Isolated volar dislocation of the distal radioulnar joint: a case series and systematic review

Introduction Isolated volar dislocations of the distal radioulnar joint are reported as rare. We observed three such cases over a 12-month period. Literature to date consists of multiple case reports and case series with no structured reviews. There is debate as to incidence, mechanism, investigation, treatment and prognosis. Methods A case series and formal systematic review was performed. This included an analysis of the demographics, mechanism, presentation, investigation, treatment and outcome of the cases identified from the wider published series. Findings In total 99 cases of this injury were identified from 59 papers, with a further 9 cases having an associated ulna styloid fracture. Conclusions This is a rare injury, representing up to 0.02% of all bony injuries, which is diagnosed late in 36% of cases. Inability to obtain a true lateral radiograph may contribute to the diagnosis being missed. Computed tomography scans are useful in suspected cases without radiographic confirmation. Acute cases are successfully treated with closed reduction in 78% of cases; however associated soft tissue injuries may need to be surgically addressed. Delayed presentation is more likely to require open surgery and preoperative MRI scans are indicated to aid surgical planning. Chronic instability rarely occurs and may need treatment with reconstruction or salvage. A good, subjective, result is reported in the majority of patients.