When asymmetrical lower limb swelling isn't a DVT
Kate Kingston, York and Scarborough Teaching Hospitals
Objective
Asymmetrical lower leg swelling requiring exclusion of deep vein thrombosis (DVT) is an extremely common,
almost reflex, ultrasound (US) request with dedicated clinical pathways and daily available scan slots. Our
departmental venous Doppler ultrasound scans are sonographer performed, largely protocol driven, with
the report mentioning the presence or absence of a Baker’s cyst. When other abnormalities are spotted
a dedicated musculoskeletal scan is arranged. We will explore the wide spectrum of pathologies we have
encountered when asymmetric lower leg swelling is not caused by a DVT.
Methods
Cases discussed in our pictorial essay were initially referred for a scan to look for DVT as a cause of their
leg swelling. Several patients had more than one DVT scan, on occasion, despite the report identifying an
alternative possible cause and suggesting further evaluation.
Results
This educational pictorial review will present the wide spectrum of causal pathologies that we have
encountered over the past 10 years in patients with unilateral lower limb or calf swelling. Some are commonly
seen such as ruptured or haemorrhagic Baker’s cysts, calf muscle tears or haematomas and cellulitis.
Accessory muscles, thrombosed popliteal artery aneurysm, abnormal lymph nodes, osteomyelitis and soft
tissue infections are less common whilst soft tissue tumours, scurvy, and elephantiasis neuromatosa from
diffuse neurofibromatosis are rare. Occasionally, these pathologies caused a distal DVT by external venous
compression. Where available we will correlate with cross sectional imaging.
Conclusion
Venous Doppler US scans are commonly performed to rule out DVT in patients with asymmetrical lower limb
swelling. In cases with no DVT but significant swelling, other causes may be encountered and where there is
high clinical suspicion, should be actively sought.