Risk stratification for the recurrence of trigger thumb after surgical release in the paediatric patient.

Trigger thumb, or stenosing tenovaginitis, is a relatively uncommon condition affecting the flexor pollicis longus tendon of children. The condition is characterized by the formation of a nodule within the tendon and thickening of the tendon sheath as it passes through the flexor pulley of the thumb at the level of the metacarpo-phalangeal joint. The optimum age for surgical intervention continues to be discussed. The aim of this study is to establish the temporal relationship and surgical variables to determine factors that may contribute to recurrence of the condition. A retrospective analysis of the entire surgical logbook and patient notes of a stand-alone consultant paediatric orthopaedic practice was scrutinized. 94 patients, 107 thumbs, over a 13-year period were operated on for trigger thumb. The recurrence rate was found to be 5.61 %. The average age of patients at primary release who went on to recurrence was 2.8 years, which is significantly younger than those that did not recur (p = 0.044). Sensitivity analysis revealed that the primary procedure at an age of less than 2.5 years confers a higher risk of recurrence. The data presented here advocate surgical release of trigger thumb after 2½ years of age, a senior surgeon as lead operator and a transverse skin incision at the level of the nodule or a more extensive "zig-zag" one to clearly see the structures to be released. We recommend that the surgeon ensures the stenosing pulley and sheath are released in their entirety.