Twenty adolescents with severe spastic deformities of the wrist (Zancolli type 3) and poor function on the House score were operated on between 2009 and 2014, and included in this retrospective cohort study. All were treated by wrist arthrodesis combining a proximal row carpectomy, curetting of the distal radius in order to imbed the capitate and a dorsal locking plate. The primary endpoint was improvement in the House score. Secondary endpoints included pre- and postoperative wrist flexion deformity, bone union, patient satisfaction regarding appearance and complications. The mean follow-up was 22 months. The mean age at the time of surgery was 16.2 years. Additional soft-tissue release was necessary in eight wrists. The mean House score improved significantly from 0.9 to 2.7. Average flexion deformity improved significantly from 66° to 10°. Bony union was achieved in all patients within 6 months. Four of the 20 patients required hardware removal because of fixed extension of the middle metacarpal. Wrist arthrodesis combining proximal row carpectomy with the use of a dorsal locking plate is a safe and reliable technique to improve function and appearance.