Abstract
Introduction
Venous thromboembolism (VTE) is a significant cause of patient morbidity and mortality, the risk of which increases in orthopaedic patients with lower limb immobilisation. This incidence should in theory reduce if the patients are ambulatory early in the treatment phase. The aim of this study was, therefore, to identify a difference in the incidence of symptomatic VTE by treating acute Achilles tendon rupture patients with conventional non-weight bearing plaster versus functional weight bearing mobilisation.
Methodology
The notes of 91 consecutive patients with acute Achilles tendon rupture were retrospectively reviewed and prospectively followed. The patients' demographics, treatment modality (non-weight bearing plaster versus weight bearing boot), and the type of plaster immobilisation was compared to assess whether they affect the incidence of clinical VTE. The predisposing risk factors were also analysed between the treatment groups.
Out of 91 patients, 50 patients with acute Achilles tendon rupture were treated conservatively in a conventional non-weight bearing immobilisation cast. From these 50 patients, 3 then underwent surgery and were therefore excluded from the results. On the other hand, 41 patients were treated with functional weight bearing mobilisation (Vacupad). Patients who did have a symptomatic thromboembolic event also had an ultrasound scan to confirm a deep vein thrombosis of the lower limb or a CT-scan to confirm pulmonary embolism.
Results
Out of the 47 patients who were treated conservatively in a non-weight bearing plaster cast, 9 patients had a thromboembolic event (19.1%). On the other hand, out of the 41 patients who were treated with functional weight bearing mobilisation, only 2 patients had a symptomatic thromboembolic event (4.2%). This was statistically significant (p=0.012). This shows that patients who are treated in a non-weight bearing plaster have about five times increased risk of developing a sypmptomatic VTE compared to those treated by functional weight bearing mobilisation. There was however no difference in the predisposing factors in patients who developed VTE compared to those who did not.
Conclusion
The incidence of symptomatic VTE after acute Achilles tendon rupture is high and under-recognised. Asymptomatic VTE after this injury is probably even higher. There is a significant decrease in the clinical incidence of thromboembolic events in patients treated conservatively with early mobilisation in the functional weight bearing boot compared to those treated in a non-weight bearing cast. There is a need for further research to define the possible benefit of thromboprophylaxis in patients treated by non-weight bearing plasters.
