What is the minimum fixation required to repair flail chest?

Context: Flail chest is associated with significant mortality risk. Chest wall repair is associated with improved outcomes; however, the optimal fixation technique is unknown. Aims: We undertook a review to assess the optimal fixation technique required in order to successfully repair flail chest. Subjects and Methods: This is a retrospective review of consecutive patients with multiple rib fractures undergoing surgical fixation. The predictive value of ratio of fractures fixed in relation to flail segment and ratio of ribs fixed in relation to flail segment was assessed by the primary outcome measure of requirement for reoperation. Results: Thirty-one patients presenting with symptomatic rib fractures were referred to a single surgeon for primary management or a second opinion following previous fixation, between August 2011 and October 2018, and underwent repair. Twenty-two patients were male (71%), and the median age was 66 years (range: 18–81). Twenty-seven patients (87%) were diagnosed with flail segment. Twenty-four patients had a “Fracture Fixation to Flail” ratio (Fx: Fl) ≥1, and none required further rib fixation, whereas three patients had Fx: Fl< 1, two of whom (67%) required further rib fixation (P = 0.0085). Twenty patients had Rx: Fl≥1, and none required further rib fixation, whereas seven patients had Rx: Fl< 1, in whom five (71%) required no further intervention and two (29%) required further rib fixation (P = 0.0598). Minimum fixation number (MFN) was calculated. MFN was achieved in 22 of 27 patients. Two of the four patients with MFN did not achieve the required refixation (P = 0.0171). Conclusions: Fx:Flmost accurately predicts the risk of underfixation and subsequent requirement for further intervention in patients undergoing operative repair of flail chest.