The authors have developed a particular surgical technique (olecranon bone resection together with anterior elbow arthrolysis) to increase the elbow's range of motion in adolescents and young adults suffering from elbow flexion contracture in obstetrical palsy sequelae. The surgical procedure was carried out in a preliminary group of 11 patients. The original procedure included a double incision: first of all by means of a posterior approach to resect the tip of the olecranon and then another incision carried out through the anteromedial aspect of the elbow, with a view to performing the anterior capsulotomy. Preoperatively, the average clinical elbow extension was 64.9°, whereas after surgery, the value increased to 43.63°. The average DASH score was 38.27 points before surgery, whereas it decreased to 29.98 points after surgery. A statistical analysis was also carried out to confirm the outcome. The procedure is reliable, is not time-consuming, and does not lead to any major complications.