Hi Kim

Thank you for bringing up this very interesting topic. Findings of a recent paper published by Tonge et al in June 2019, suggest that application of TCC in DFU patients without other comorbidities that increase risk of DVT does not require routine deep venous thrombosis (DVT) chemical prophylaxis.[1] According to the study, TCC itself does not seem to pose an increased risk to DVT. However patients and risks assessed for DVT should be evaluated individually on a case by case basis. Patients may have other comorbidities (e.g. fractures, cancer, thrombophilia, etc) that result in increased risk. If assessment indicates increased risk for DVT, chemical prophylaxis should be initiated. Risk assessment tools for DVT such as the one provided by NICE can be utilized [2] This retrospective study by Tonge et al [1], evaluated 100 patients treated with TCC, 75 of these had neuropathy secondary to diabetes. No patients received chemical thromboprophylaxis while in a cast (average time in cast was 45 days), and only one episode of DVT was recorded. Compared to the general population, frequency of DVT in this group was slightly higher, but authors noted that this was due to the comorbidities that this one patient had, which increased his risk for DVT (i.e. cancer, etc). 

One of the reasons behind the low rates of DVT while using TCC is that patients can bear weight through the cast, and calf muscle pump is still active, preventing venous stasis, despite mobilization of the ankle.[3] Unlike other patients who are prescribed lower limb cast or brace due to leg injuries such as foot and ankle fractures and achilles ruptures, patients with DFU who require offloading usually do not have associated injuries that prevent weight bearing completely and increase risk for DVT. Patients who are immobilized with cast/brace due to such leg injuries do benefit from routine DVT chemical prophylaxis though.[4] Regardless, as a simple, non-chemical strategy for DVT prophylaxis, all patients receiving TCC may be prescribed a toe dorsiflexion/ plantar flexion and knee exercise program.[1] 

Hope this helps! Thank you.

[1] Tonge et al, 2019 https://www.ncbi.nlm.nih.gov/pubmed/31154840
[2] Risk assessment tool for DVT https://www.nice.org.uk/guidance/ng89/resources/department-of-health-vte-risk-assessment-tool-pdf-4787149213
[3] Hickey et al 2014 https://www.ncbi.nlm.nih.gov/pubmed/24719402
[4] Aniek et al 2017 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6483324/

Thank you so much! Exactly what I needed for our team!

Glad to hear, thanks Kim.