Modified Peterson bunion procedure. A, Medial longitudinal incision extends from base of first metatarsal to base of proximal phalanx with flaps from extensor hallucis longus tendon plantarward. B, Distally based osteoperiosteal flap is raised with 1-mm-thick bone cut after subperiosteal stripping of first metatarsal. C, Flap is retracted distally, exposing sulcus to remove remaining bunion. D, Distal closing wedge at base of bunion cut. Width of medial wedge equal to sine of hallux valgus angle multiplied by diameter of metatarsal. Attempt is made to greenstick osteotomy laterally. E, Proximal osteotomy made with saw and “greensticked” laterally allows space for one 3.5-mm screw. Plate is selected that fits adjusted length of metatarsal with proximal opening wedge graft inserted and distal osteotomy closed. Proximal screw is placed loosely into plate, allowing osteoperiosteal flap to be pulled under distal end of plate, while correcting great toe into supination. F, Periosteum closed over proximal plate and distally to osteoperiosteal flap. Abductor tendon is pulled up to its normal medial position. G, Appearance of foot after completed osteotomies and plate fixation. (A-F from Aronson J, Nguyen LL, Aronson EA: Early results of the modified Peterson bunion procedure for adolescent hallux valgus, J Pediatr Orthop 21:65, 2001; G courtesy Dr. James Aronson, Little Rock, AK.) SEE TECHNIQUE 82.22.