Abstract
Introduction
Several hexapod external fixator devices are used in the treatment of bone fracture and deformity corrections. One characteristic of all of them is the requirement for manual adjustment of the fixator struts. The purpose of this study was to introduce a novel robotic system that executes automatic adjustment of the struts.
Materials and Methods
Ten patients were treated for various bone deformities using a hexapod external fixator with Auto Strut system, which implemented automatic adjustment of the fixator struts. Patients arrived at the clinic for follow during the correction period until the removal of the hardware. During each visit, the progress of the correction was assessed (clinically and radiographically) and reading of the strut scale numbers was performed.
Results
All patients completed the treatment plan during the follow up period achieving all planned correction goals. Healing of the bone ranged between approximately one to seven months. Duration of distraction ranged between 10 and 90 days. The distraction index ranged between 8 and 15 days/cm. The length of distraction varied between 1 and 6 cm. The planned corrections were fully attained in all patients who completed the treatment (n=10). No device related adverse events were reported. One patient was not available for registration of struts length, one patient switched to manual struts due to personal preference.48 struts of eight patients were recorded, 94% of the final strut number readings presented a displacement of 0–1 mm, three struts (6%) had 2–3 mm displacement due to inter-observer reading errors. indicating high precision of the automatic adjustment.
Conclusions
This study presents preliminary result, showing that Auto Strut can successfully replace the manual strut adjustment providing important advantages that benefit the patient, the caregiver and the surgeon.
