Effect of soft tissue injury and ulnar angulation on radial head instability in a Bado type I Monteggia fracture model

Abstract

The effects of soft tissue damage and ulnar angulation deformity on radial head instability in Monteggia fractures are unclear. We tested the hypothesis that radial head instability correlates with the magnitude of ulnar angular deformity and the degree of proximal forearm soft tissue injury in Bado type I Monteggia fractures.We performed a biomechanical study in 6 fresh-frozen cadaveric upper extremities. Monteggia fractures were simulated by anterior ulnar angulation osteotomy and sequential sectioning of ligamentous structures. We measured radial head displacement during passive mobility testing in pronation, supination, and neutral rotation using an electromagnetic tracking device. Measurements at various ligament sectioning stages and ulnar angulation substages were statistically compared with those in the intact elbow.Radial head displacement increased with sequential ligament sectioning and increased proportionally with the degree of anterior ulnar angulation. Annular ligament sectioning resulted in a significant increase in displacement only in pronation (P < .05). When the anterior ulnar deformity was reproduced, the radial head displaced least in supination. The addition of proximal interosseous membrane sectioning significantly increased the radial head displacement in supination (P < .05), regardless of the degree of anterior ulnar angulation.Our Monteggia fracture model showed that radial head instability is influenced by the degree of soft tissue damage and ulnar angulation. Annular ligament injury combined with a minimal (5°) ulnar deformity may cause elbow instability, especially in pronation. The proximal interosseous membrane contributes to radial head stability in supination, regardless of ulnar angulation, and proximal interosseous membrane injury led to significant radial head instability in supination.

Two-stage strategy for neglected Monteggia fracture in children

“…[ 16 , 17 ] Moreover, certain authors recommend UO combined with open reduction of RHD. [ 18 – 20 ] Although all the authors reported improved outcomes after surgeries, complications are common, including radial head subluxation and instability.…”

“…Over-distraction during the surgery increased the risk of delayed union or nonunion of osteotomy site, nerve palsy and postoperative compartment syndrome. [ 7 , 16 – 18 , 23 ] Besides, the gap of the osteotomy site should be filled with bone graft. [ 7 , 23 ]…”

Heterotopic Ossification of annular ligament: A case report and review of literature

“…8,9 While many treatment options are available two important modalities commonly followed are 1) ulnar osteotomy with lengthening and 2)annular ligament reconstruction. The principle of Ulnar osteotomy is explained by Hayomi et al 10 in their biomechanical evaluation. When there is no anterior ulnar angulation, even with sectioning of the annular ligament and the capsule of the elbow joint there was no significant anterior displacement of the radial head.…”

Effect of Vacuum Sealing Drainage on Soft Tissue Injury of Traumatic Fracture and Its Effect on Wound Recovery

“…From an ergonomic point of view, the mechanical behavior of the whole tissue will change dramatically if the soft tissue is damaged, which in turn suggests that biomechanical changes caused by STIs can be used to detect the severity of the injury [ 6 , 7 ]. In any event, all kinds of STIs must be considered when detecting and treating TFs [ 8 ]. Hence, research on the treatment of STIs and wound recovery has important practical value for improving patient outcomes and avoiding wound infection and necrosis.…”