In a retrospective study the results of conservative and operative treatment of mallet fingers (n = 86) were evaluated. The results of Stack splint therapy (n = 59) were disappointing. There was a good result in only 32%. Mallet fingers associated with avulsion fracture (n = 24) give better results (42% 'good') than mallet fingers due to tendon rupture (n = 35) (26% 'good'). With operative treatment (n = 27), consisting of tenodermodesis in combination with internal Kirschner wire fixation, there was a good result in 89%. Surgery was used not only if conservative treatment failed, but also as primary therapy. In case of tendogenous mallet finger the results of surgery are significantly better than those of conservative therapy (p less than 0.00001). Based on our retrospective study we suggest that the tenodermodesis with K-wire fixation be considered not only in cases where conservative treatment fails, but also as primary treatment of tendogenous mallet finger. In mallet finger with avulsion fracture conservative treatment appears to be the treatment of choice.