Previous results following subfascial endoscopic perforator vein surgery were reported to be worse in post-thrombotic syndrome than in limbs with primary valvular incompetence. This report comprises a larger patient cohort with longer follow-up. The goal of this study was to determine if subfascial endoscopic perforator vein surgery is justified in patients with post-thrombotic venous insufficiency. The clinical data of 91 consecutive patients who underwent subfascial endoscopic perforator vein surgery with or without superficial reflux ablation over a 7-year period from May 1993 to June 2000 were retrospectively analyzed. Fifty-four females and 37 males (median age, 53 years; range, 20-77) underwent 103 subfascial endoscopic perforator vein surgery procedures. Forty-two limbs were classified as C6 (active ulcer), 34 as C5 (healed ulcer), and 24 as C4 (lipodermatosclerosis). Thirty procedures were performed in post-thrombotic limbs. Concomitant superficial reflux ablation was performed in 74 limbs (72%); saphenous vein stripping had been previously performed in 29 (28%). Deep venous incompetence was present in 89% of limbs; 13% had venous outflow obstruction on plethysmography. Cumulative ulcer healing in post-thrombotic limbs was not significantly different from limbs with primary valvular incompetence; 30-, 60-, and 90-day healing rates were 44%, 72%, and 72% vs 39%, 70%, and 87%, respectively (p = 0.35). On univariate analysis, the presence of ulcer greater than 2 cm in diameter was associated with delayed ulcer healing (p = 0.02). Cumulative ulcer recurrence in all limbs was 4%, 20%, and 27% at 1, 3, and 5 years, respectively. Ulcer recurrence in post-thrombotic limbs was higher than in limbs with primary valvular incompetence at 1, 3, and 5 years; 16%, 47%, and 56% vs 0%, 8%, and 15%, respectively (p = 0.001). Recurrent ulcers were small, superficial, and easier to heal. Clinical improvement was significant even in post-thrombotic limbs; median clinical score decreased from 9.5 to 3 (p = 0.001), and median outcome score was +2 (mean 1.9; range, -1 to 3). Median clinical score in patients with primary valvular incompetence improved from 6 to 1.5 (p = 0.0001). Subfascial endoscopic perforator vein surgery with superficial reflux ablation promoted ulcer healing, improved clinical outcome, and resulted in a low long-term ulcer recurrence rate in limbs with primary valvular incompetence. Despite good clinical outcome in post-thrombotic limbs, ulcer recurrence was high. These results imply that the role of subfascial endoscopic perforator vein surgery with superficial reflux ablation in patients with post-thrombotic limbs continues to be controversial.