STOP leg clots-Swedish multicentre trial of outpatient prevention of leg clots: study protocol for a randomised controlled trial on the efficacy of intermittent pneumatic compression on venous thromboembolism in lower leg immobilised patients

BMJ Open. 2021 May 20;11(5):e044103. doi: 10.1136/bmjopen-2020-044103.


Introduction: Leg immobilisation in a cast or an orthosis after lower limb injuries is associated with a high risk of complications of venous thromboembolism (VTE) and hampered healing. Current pharmacoprophylaxes of VTE are inefficient and associated with adverse events. Intermittent pneumatic compression (IPC) could represent a novel, efficient and safe VTE-prophylactic alternative that may enhance injury healing. The aim of STOP leg clots is to assess the efficacy of adjuvant IPC-therapy on reduction of VTE incidence and improvement of healing in lower leg immobilised outpatients.

Methods and analysis: STOP leg clots is a multicentre randomised controlled superiority trial. Eligible patients (700 patients/arm) with either an acute ankle fracture or Achilles tendon rupture will be randomised to either addition of IPC during lower-leg immobilisation or to treatment-as-usual. The primary outcome will be the total VTE incidence, that is, symptomatic and asymptomatic deep venous thrombosis (DVT) or symptomatic pulmonary embolism (PE), during the leg immobilisation period, approximately 6-8 weeks. DVT incidence will be assessed by screening whole leg compression duplex ultrasound at removal of leg immobilisation and/or clinically diagnosed within the time of immobilisation. Symptomatic PE will be verified by CT.Secondary outcomes will include patient-reported outcome using validated questionnaires, healing evaluated by measurements of tendon callus production and changes in VTE-prophylactic mechanisms assessed by blood flow and fibrinolysis. Data analyses will be blinded and based on the intention-to-treat.

Ethics and dissemination: Ethical approval was obtained by the ethical review board in Stockholm, Sweden, Dnr 2016/1573-31. The study will be conducted in accordance with the Helsinki declaration. The results of the study will be disseminated in peer-reviewed international journals.

Trial registration: NCT03259204.

Time schedule: 1 September 2018 to 31 December 2022.

Keywords: anticoagulation; foot & ankle; orthopaedic & trauma surgery; orthopaedic sports trauma; thromboembolism; ultrasound.

Publication types

  • Clinical Trial Protocol
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Humans
  • Intermittent Pneumatic Compression Devices
  • Leg
  • Multicenter Studies as Topic
  • Outpatients
  • Randomized Controlled Trials as Topic
  • Sweden
  • Venous Thromboembolism* / prevention & control
  • Venous Thrombosis* / prevention & control

Associated data