Plate or Screw Fixation in Proximal Phalangeal Fractures: An Interim Analysis of the POSI-P1 Trial

BACKGROUND: Phalangeal fractures are common, with no consensus on their ideal management. The aim of this interim analysis is to compare outcomes following dorsal plating, lateral plating or intramedullary screw fixation of displaced extra-articular proximal phalangeal fractures in an adult population. METHODS: A multicentre randomized controlled trial was conducted across 8 sites in Australia. Patients aged 18 years or older with closed extra-articular proximal phalangeal fractures who were able to undergo intervention within 14 days of injury were eligible for inclusion. Included patients were randomized to fixation via either dorsal plating, lateral plating or intramedullary screw stabilization. Patients were assessed at 6 weeks, 3 months, 6 months and 1 year. The primary outcome assessed was total active motion. Secondary outcomes included grip and lateral pinch strengths, patient-reported outcome measures, and both major and minor complications. RESULTS: A total of 101 patients with 107 fractured proximal phalanges were recruited, with treatment groups of 42 digits (41 patients) for dorsal plating, 32 digits (30 patients) undergoing lateral plating and 33 digits (30 patients) receiving intramedullary screws. No difference was noted in any parameter, bar length of surgery (favouring intramedullary screws) and major complications (favouring both intramedullary screws and lateral plating). CONCLUSIONS: This interim analysis finds no difference in total active motion or patient- and clinician-reported outcome measures between the 3 interventions. Both dorsal plating and lateral plating require more surgical time to perform the intervention. Dorsal plating is significantly more likely to result in a major complication. TYPE OF STUDY: Multicentre randomized controlled trialLevel of Evidence:Therapeutic IIb.