The treatment of idiopathic and non-idiopathic vertical talus using the Dobbs method- a long- term study with a follow-up of up to 16 years- relapses, residual deformities and reoperations.

INTRODUCTION

Treating vertical talus using the minimally invasive method according to Dobbs is becoming increasingly more common and appears to reduce the need for extensive surgery. In this paper, we report on the long-term findings for treating these idiopathic and non-idiopathic deformities.

MATERIALS AND METHODS

Twenty-three vertical talus deformities were treated between 11/2007 and 12/2014. Treatment was primarily carried out using the minimally invasive Dobbs method with reverse Ponseti casting. Patient data, treatment data, surgical methods, relapse rates, functional results and weight-bearing imaging results were documented over the course of the study. The talar axis-first metatarsal base angle (TAMBA) was used to assess the severity of the deformity. Long-term clinical findings and imaging were presented.

RESULTS

Nineteen vertical talus deformities were examined over an average follow-up period of 10.4 years. A minimally invasive primary correction was performed on 74% using the Dobbs method. More extensive surgical measures were necessary in 26,3%. The relapse rate was 26.3%. In the group with idiopathic deformities the average long-term range of motion of the ankle joint was 17.5° dorsiflexion and 36° plantarflexion, in the group with non-idiopathic deformities it was 9.2° dorsiflexion and 12.4° plantarflexion. The average preoperative TAMBA for the entire cohort was 65°; postoperatively it was 13°. In the group of feet that underwent a minimally invasive correction procedure, these values were 51° preoperatively and 11° postoperatively. In 79% we achieved excellent and good results according to the radiological classification system of Hamanishi over the long term.

CONCLUSION

Using the minimally invasive Dobbs method to treat vertical talus significantly reduces the need for extensive surgery and also leads to good, long-term functional results, especially for idiopathic deformities. More extensive arthrolysis to correct the deformity may still be warranted in cases of non-idiopathic deformities. Non-idiopathic deformities, residual pathologies, and changes in foot deformity not related directly to a vertical talus pathology leads to higher long-term reoperation rates.