One of the functions of the lymphatic system is to transport proteins and fat molecules that are too large to enter venules from the interstitial tissue to the central cardiovascular system.  The system consists of lymphatic vessels that intertwine with the arterial and venous capillary bed, these vessels then transport the fluid and molecules to precollectors, then collectors to lymphatic trunks to regional lymph nodes.  When chronic venous insufficiency (CVI) prevents accommodation of the normal amount of venous flow, the lymphatic system compensates by increasing its transport volume up to 10 times normal amounts.  If the amount of fluid exceeds what the venous and lymphatic systems can transport, secondary lymphedema develops.  If not treated effectively at the onset, this chronic inflammatory condition will lead to deposition of collagen fibers and adipose cells in the interstitial tissue of the affected region, and a different treatment regimen is indicated. 

The risk factors for CVI and lymphedema are very similar, as are the initial complaints of heaviness, tightness, aching, and sometimes sensory changes.  There is initial loss of skin mobility that becomes tighter and less mobile as the condition progresses, thus limiting range of motion and impairing function.  One of the clinical symptoms that may differ is the extent of edema.  In CVI the edema is usually limited to below the knee, whereas in secondary lymphedema it may progress up the thigh.  The skin changes are similar to CVI; however, there may also be a positive Stemmer sign in which the clinician is unable to pinch or tent the skin the distal foot. 

The table below emphasizes some of the differences in treatment strategies for CVI and lymphedema. 

The primary differences are in the exercises and compression.  CVI exercises focus on activating the venous pump, i.e. gastroc-soleus muscles, whereas lymphedema exercises focus on return of the lymph fluid to the central system via deep breathing exercises, joint range of motion to compress lymph nodes, and aerobic exercises.  Compression for CVI (without arterial compromise) consists of a multi-layer system from the toes to just below the popliteal fossa because the purpose is to get the fluid to the popliteal vein.  Compression for lymphedema usually is from toe to thigh and consists of multiple layers of foam, gauze rolls, soft padding, and short stretch bandages of various widths.  Compression is combined with manual lymphatic drainage to mobilize the fluids prior to application of compression.

Successful long-term treatment of both disorders involves continued compression therapy with the appropriate length garments, exercise, and meticulous skin care.  A complete discussion of lymphedema, its physiology, pathophysiology, differential diagnosis, and treatment is available at the following link: 

Perdomo M, Hamm R.  Lymphedema. In Hamm R (Ed), Text and Atlas of Wound Diagnosis and Treatment: 2^nd edition.  New York: McGraw Hill Education.  2019, 145-169.  Available at https://accessphysiotherapy.mhmedical.com/book.aspx?bookid=1334