Cyclical micromovement and fracture healing

Area of Science:

• Orthopedic surgery
• Biomedical engineering
• Traumatology

Background:

• Tibial shaft fractures are common injuries requiring effective fixation.
• External fixation is a common treatment modality for these fractures.
• Optimizing healing time and minimizing complications are key goals in fracture management.

Purpose of the Study:

• To compare the efficacy of three external fixation methods for tibial shaft fractures.
• To evaluate the impact of axial dynamisation versus cyclical micromovement on fracture healing.
• To assess the incidence of pin-track infections associated with different fixation techniques.

Main Methods:

• A multicentre prospective randomised trial involving 56 patients with tibial shaft fractures.
• Three groups were studied: Group I (axial dynamisation), Group II (delayed spring fixation), and Group III (early spring fixation with micromovement).
• Fracture healing was assessed by measuring fracture stiffness, with healing defined as 15 Nm/degree.

Main Results:

• Mean healing times were 14.1 weeks (Group I), 15.9 weeks (Group II), and 19.3 weeks (Group III), with statistically significant differences (p=0.004).
• Early cyclical micromovement (Group III) resulted in an average delay of 1.8 to 8.7 weeks compared to axial dynamisation (Group I).
• Pin-track infections occurred in over 60% of patients in the micromovement groups versus 20% in the axial dynamisation group (p=0.03).

Conclusions:

• Delayed axial dynamisation appears to promote faster healing of tibial shaft fractures compared to early cyclical micromovement.
• Early initiation of micromovement in external fixation may be associated with a higher risk of pin-track infections.
• Further research may be needed to clarify the role of patient selection in outcomes.