Aims: We evaluated a novel modification of a technique presented by Drey and Eaton (1993). The need of temporary K-wire fixation of the MP joint was questioned by randomisation. Methods: 30 consecutive patients with late instability of the thumb UCL were randomised in two groups (group1: K-wire fixation of the MP joint for 6 weeks, group 2: no internal fixation) and operated on. External immobilisation was used for 6 weeks in both groups. The follow-ups including clinical examination, X-rays and MRI study (10 patients) were at 8 weeks, 12 and 24 months. So far 26 patients have been followed up for 1 year and 15 patients for 2 years. Results: Stability of the MP joint improved from preop.(average yield) 58o (56°vs.59°= group 1 vs. group 2, n.s.) to 18° (17° vs. 19°n.s.) at one year and to 26°(20°vs. 30°n.s.) at 2 years. Compared to the uninjured hand key pinch strength improved from preop. 74% (81% vs. 69% n.s.) to 95% (97% vs. 93% n.s.) at 1 year and to 100% (102% vs. 98% n.s.) at 2 years. The pulp pinch strength improved from preoperative 65% (68% vs. 63% n.s.) to 98% (98% vs. 97% n.s.) at 1 year and to 108% (109% vs. 107% n.s.) at two years. 18 (69%) of 26 patients (73% vs. 67%) followed at least 1 year revealed the result as good or excellent, 6 (23%) patients (27% vs. 20%) revealed the result as fair and 3 (12%) patients (9% vs.13%) revealed the result as poor. All patients returned to their previous work. Conclusions: This new technique provided good improvement in stability and strength of the thumb. Temporary K-wire fixation of the MP joint seems to have no influence on the outcome so far.