JOINT SCIENTIFIC RESEARCH CENTRE - BIOMECHANICAL LABORATORY OF THE UNIVERSITY HOSPITAL OSTRAVA

INTRODUCTION

Biomechanical Laboratory of the University Hospital Ostrava is an open interdisciplinary scientific, research and educational centre built in close interdisciplinary cooperation between the Traumatology Centre of the University Hospital Ostrava and the Institute of Disaster Medicine of the Faculty of Medicine of the University of Ostrava, the Centre for Advanced Innovative Technologies of VSB - Technical University of Ostrava and other partners from the private sphere engaged in the development and production of modern osteosynthetic materials and prosthetic-orthotic therapeutic aids. The Biomechanical Laboratory is equipped with modern technological devices enabling measurement of the limb load during the patient‘s gait after surgery of lower limb fractures with continuous monitoring by an electronic system with recording and evaluation of the postoperative gait stereotype (Fig. 1).

Based on the result of electronic monitoring of limb load, it is possible to clinically evaluate the effect of limb load values on fracture healing after internal osteosynthesis and the effect of the achieved dosed compression and distraction of the fracture on treatment of open fractures of the lower limbs with external fixators (Fig. 2).

Evaluation of the effect of dosed compression and distraction on the treatment of open fractures with external fixation

We use osteosynthesis with external fixation to treat grade 2 and 3 open fractures of the lower limbs. Since it is a minimally invasive osteosynthesis, which, unlike stable internal osteosynthesis, allows the use of gradual compression and distraction of the fracture site during fracture healing, in an interdisciplinary cooperation with CAIT of VSB - Technical University Ostrava, we have developed compression-distraction measuring sensors for the external fixator of Ilizarov type, which allow to measure the pressure at the fracture site during its healing (Fig. 3).

To evaluate the effect of the dosed compression and distraction on the treatment of open fractures by external fixation, we investigate the effects of load at different levels and timing of mechanical stimulation in the treatment of fractures using the Ilizarov fixators with measuring sensors (Fig. 4). We hypothesize that different levels of mechanical stimulus result in different degrees and rates of fracture healing.

Effect of earlier load on the healing of calcaneal fractures

After internal osteosynthesis of fractures in the lower limbs, patients must gradually load the operated limb with their body weight while walking with crutches. The scope of load is determined by the clinical and radiographic findings of the extent of fracture healing. The limb load is measured at 1/3 of the patient‘s body weight, then at 1/2 up to full walking load without crutches. Since as of yet, the magnitude of this load is currently not continuously monitored at any institutions, we initiated monitoring of the load rate in the Biomechanical Laboratory after calcaneal fracture surgeries to assess the correlation between the postoperative load rate and fracture healing and callus growth stimulation.

Patients are monitored for varying levels of limb load and we assess how the magnitude of load translates into mechanical stimulation of the callus growth. The monitoring is performed by an electronic system for recording and evaluating the foot pressure distribution in static both and dynamic conditions - a plantography platform. It is also a diagnostic method of monitoring the physiological stereotype of gait and load. The plantography platform, with its electronic system, records and evaluates the foot pressure distribution in static and dynamic conditions of the patient‘s gait, thus providing information for the analysis and diagnosis of pathophysiological and functional deviations.

Using a plantography platform in stable osteosynthesis of the calcaneus, we examine the degree of load the patient transfers to the operated limb in the postoperative period at 6, 12, 18 and 24 weeks after the surgery.

Thus, we obtain accurate information for the diagnosis of gait, the detection of deformities, deviations from the physiological stereotype of gait and the time course of limb load, which allows the attending physician to accurately determine the magnitude of the load on the operated limb when walking with crutches and subsequently evaluate its contribution to fracture healing, which is evaluated clinically, using radiograms and sonography.

Conclusion

This paper was supported by project No. CZ.02.1.01/0.0 /0.0/17_049/0008441 „Innovative Therapeutic Methods of Musculoskeletal System in Accident Surgery“ within the Operational Programme Research, Development and Education financed by the European Union and by the state budget of the Czech Republic.