Clinical and radiological short- and mid-term results of triple pelvic osteotomy according to Tonnis in adolescents and adults

Aim: We report our clinical and radiological results after triple pelvic osteotomy according to Tonnis and accompanying femoral osteotomies in selected cases. Method: 48 patients were evaluated in a retrospective study with an average follow-up to 2 years and 9 months. Results: In 68% of our patients excellent to good results in the Harris Hip Score were achieved. We could significantly decrease pain awareness. The CE angle improved significantly from 10.6degrees to 32.2degrees and the acetabular angle of the weight-bearing zone according to Bombelli from 20.8degrees to 3.8degrees at the last follow-up. The VCA angle according to Lequesne and de Seze improved from 18.6degrees to 33.5degrees. Non-union of the ischial or the pubic bone developed in 7 cases as a relevant complication. Conclusion: On the basis of our results and the literature, the triple pelvic osteotomy according to Tonnis can be recommended for the treatment of acetabular dysplasia in adolescents and adults.