A total of 2,624 groin operations were performed in 2,202 infants and children aged 6 months-14 years during the last 4.5 years. Preventive analgesia was used in all operations, and included ilioinguinal and iliohypogastric nerve block combined with inguinal canal infiltration. In 6 patients transient postoperative quadriceps muscle paresis (QMP) was noted. They required bed rest and monitoring for a few hours, and complete spontaneous recovery was noted in all cases. The aim of this study was to examine the incidence of transient QMP following regional nerve block and to discuss models of possible prevention.