Does partial weight bearing unload a healing bone in external ring fixation?

Abstract

Partial weight bearing did not unload the defect zone. No direct relationship between interfragmentary movement magnitudes and ground reaction forces was identified. Therefore, the concept of partial weight bearing cannot reliably reduce loading of a healing zone. It may, however, help to prevent patients from undergoing critical situations, such as stumbling, by increasing their general awareness.

Partial weight bearing after surgery for fractures of the lower extremity – is it achievable?

“…Firstly, it is thought to protect and relatively unload healing bone thus supporting the stability of the reconstruction and the surgical result in the early postoperative phase. Six patients with tibial osteotomies stabilized with external ring fixators could not reliably reduce loading of the healing zone during partial weight bearing in three dimensional interfragmentary movement measurements with reflective markers [21]. The authors concluded that partial weight bearing was only helpful to prevent patients from extreme loading such as a stumbling which might cause a major increase in ground contact forces.…”

“…Few studies have demonstrated the limitations of the concept of partial weight bearing [19,20]. The methods applied varied from biomechanical testing to force platform data and animal experiments [12,16,19,21]. However, given loads of partial weight bearing have never been tested during dynamic gait phases.…”

Experimental model for controlling shear using the Ilizarov frame

“…As with any biomechanical study, whilst anatomical constraints have been taken into account with hardware positioning, it is impossible to replicate for the effect of soft tissue structures. It has been noted in other studies that simple co-contraction of muscles can apply up to a 200 N force without load bearing (Duda et al, 2003). This study assumes full weight bearing on day one and does not take in to account the temporal effect of callus formation and strength over the period of frame use (Joslin et al, 2008;Vijayakumar et al, 2006).…”

A visão do ortopedista brasileiro sobre a descarga parcial de peso em ortostase nas fraturas expostas da diáfise da tíbia após osteossíntese

“…Duda et al 26 measured the impact of partial weight bearing while standing 14 days after EF. The authors found that partial weight bearing helped raise patient awareness and did not affect consolidation.…”