During examination of a leg with varicose veins, the long saphenous vein is emptied by elevating the limb, a tourniquet is applied below the knee, and the patient stands. The varicosities do not refill while the tourniquet remains. On releasing the tourniquet, rapid filling occurs from above downwards. This indicates:
- A Incompetent communicating (perforator) veins below the knee
- B Deep venous obstruction
- C Incompetent saphenofemoral junction with competent perforators ✓
- D Incompetent short saphenous system
Correct answer: C. Incompetent saphenofemoral junction with competent perforators
Explanation
In the modified Perthes or tourniquet test, control of reflux from above prevents refilling, proving the source of incompetence lies at or above the tourniquet level, classically the saphenofemoral junction. Rapid downward filling immediately after release confirms downward reflux through the long saphenous vein. Refilling despite the tourniquet would implicate incompetent below-knee perforators, and deep obstruction worsens symptoms on standing rather than causing this pattern.
Reference: Bailey and Love's Short Practice of Surgery, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.