DVT Tests | Deep Venous Thrombosis Diagnosis

Deep Vein Thrombosis tests (DVT tests) include the following:

1. Homans sign
2. Perthes Test
3. Trendelenburg Test
4. Lowenberg Test
5. Schwartz test.

Homan’s Sign

This was the traditional test used to detect a deep vein thrombophlebitis (DVT).

The patient lies in the supine position with their knee extended. The clinician stabilizes the thigh with one hand and passively dorsiflexes the patient’s ankle with the other. Pain in the calf with this maneuver was considered a positive sign for DVT.

However, a positive Homan’s sign has been found to be insensitive, nonspecific, is present in fewer than 30% of documented cases of DVT, and the performance of the test may increase the risk of producing a pulmonary embolism (PE).

See Also: Homans Test for DVT

Perthes Test

Perthes Test assesses the function of deep veins and perforating veins.

With the patient standing, the examiner applies a tourniquet to the thigh or lower leg proximal to the filled varices. The patient is then asked to walk around with the tourniquet in place.

• Complete emptying of the varices as a result of muscular activity indicates proper function of the perforating veins and intact deep venous drainage. The congestion is attributable to valvular insufficiency in the saphenous vein.
• Incomplete emptying is observed where there is moderate valvular insufficiency of the communicating veins.
• Unchanged filling in the varices occurs with significant insufficiency of the perforating veins and impaired blood flow in the deep veins.
• An increase in filling suggests a severe post thrombotic syndrome with reversed blood flow in the perforating veins.

Trendelenburg Test

Trendelenburg Test assesses varicose veins in the thigh. Tests the function of the lesser saphenous
vein and perforating veins.

With the patient supine and the leg raised, the examiner smoothes the distended veins. The examiner then compresses the greater saphenous vein with a tourniquet distal to its junction with the femoral vein at the inguinal ligament and asks the patient to stand up:

• If the varices only fill up slowly or not at all within 30 seconds of the patient standing up but then fill rapidly from proximal once the tourniquet is loosened, this indicates valvular insufficiency of the saphenous vein with normal function of perforating veins.
• Relatively rapid filling from distal can occur as a result of insufficient perforating veins or anastomoses with an insufficient lesser saphenous vein.
• Rapid filling of the varices from both distal and proximal once the tourniquet is released indicates insufficiency of both the greater saphenous vein and the communication with the deeper venous system.

Lowenberg Test

Lowenberg Test is an early sign of venous thrombosis.

The examiner applies blood pressure cuffs to each lower leg and pumps them up.

Normally, discomfort will occur only beyond 180 mm Hg (24 kPa). Where thrombosis is present, the normal leg will be observed to tolerate compression of the calf musculature with far higher pressure than the affected leg.

Schwartz test

The Schwartz test or the percussion method of Schwartz and Hackenbruch is used to assess valvular insufficiency in the region of the greater saphenous vein.

With the patient standing, the examiner places one finger on the distended vein being examined and taps on the junction of the greater saphenous and femoral veins with one finger of the other hand. If this tapping is transmitted back to the first finger, the blood flow is continuous, indicating that the valves in the portion of the vein being examined are not intact.

The Schwartz test is not necessarily definitive, but it is a good method for determining whether a superficial venous branch communicates with the greater or lesser saphenous vein.

References

1. Aschwanden M, Labs KH, Engel H, Schwob A, Jeanneret C, Mueller-Brand J, Jaeger KA. Acute deep vein thrombosis: early mobilization does not increase the frequency of pulmonary embolism. Thromb Haemost. 2001 Jan;85(1):42-6. PMID: 11204585.
2. Evans RC: Illustrated Essentials in Orthopedic Physical Assessment. St. Louis, MO: Mosby-Year Book, 1994.
3. Clinical Tests for the Musculoskeletal System 3rd Edition.
4. Dutton’s Orthopaedic Examination, Evaluation, And Intervention 3rd Edition.
5. Sarvdeep S. Dhatt, Sharad Prabhakar – Handbook of Clinical Examination in Orthopedics.