Forty-nine ununited fractures were compressed after the bone ends had been countersunk by open operation, with one exception. This patient, Case 2 (Figs. 9-A through 9-C), had compression alone, without exposure of the bone ends, and bone union resulted. Forty-one fractures (83.7 per cent), united. Twelve of the thirteen with sinuses before operation united. When the fractures united, the sinuses healed. Four recent fractures with gross displacement united.