The closed method for the treatment of compound fractures of the limbs emerged and popularised during the interwar period. The historiography on this procedure sustains an essentially Anglo-Saxon narrative focusing on contributions by the American surgeon Winnett H. Orr during the First World War and the Spanish Josep Trueta during the Spanish Civil War and his exile in Britain. This paper aims to ‘open’ this story by reconstructing the early work of another Spanish surgeon: Manuel Bastos. Although originally an army medical officer, Bastos specialised in the treatment of limb fractures in a dual military-civilian context. On the one hand, during successive assignments to the Spanish Protectorate in Morocco, he familiarised with the management of gunshot wounds. On the other hand, he specialised in the treatment of tuberculosis humerus fractures in children at the Instituto Rubio in Madrid. The visit to Spain of the Argentinian surgeon Pedro Chutró, who had acquired a great prestige in First World War Paris for his approach to fractures and osteomyelitis, and the escalation of the Moroccan campaigns to the so-called Rif War (1921–27) gave Bastos the opportunity, the idea, and the courage to develop a closed treatment of humerus fractures in soldiers. Chutró’s influence on Bastos persisted in the context of the Hispano-Americanist policy embraced in mid-twentieth-century Spain. Ultimately, this study questions the understanding of the closed method as a single, univocally traceable procedure, suggesting instead parallel versions emerging in different sites and transforming themselves and influencing each other as they circulated globally.