Closed Extension Block Technique for Treatment of Osseous Mallet Injury

Objectives: We analyzed the clinical and radiological outcomes of percutaneos extension block technique for treatment of osseous mallet injury. Methods: We included 36 patients who had osseous mallet finger ≥ 20% articular surface involvement. We controlled 29 men, 7 women followed mean 18,5 ( Range 8 – 24) months.Radiologic evaluation was made according to the Doyle classification and 25 injuries were classified type IVb, 11 injuries were classified type IVc. Final evaluation were made according to Crawford evaluation criteria and distal interphalangeal joint motion.Results: The preoperative avarage articular surface involvement was 39,7% ( Range 20 – 60 ). The DIP joint subluxation was seen in 6 patients who had ≥50% articular surface involvement. Clinical results, according to the Crawford criteria, were excellent in 30 ( 83,3% ) patients, good in 4 patients ( 11,1% ), moderate in 2 patients ( 5,5% ). The average extension lag was 3,1° (0°to 17°), and the average final active flexion of DIP joint was 75,1° (50° to 80°). Bone union was showed in all cases radiographically at the final control. Conclusion: The extension block technique is a minimal invasive treatment technique. This technique has decreased the complications of the open surgical treatments. This technique when properly applied has been given functionally satisfactory results. The experience of the surgeon is very effective over the result of the patients.