Fig. 9.

a To perform the shifting manoeuvre and lateralisation of the metatarsal head, a small elevatorium is introduced through the portal and placed insides the medullary canal of the MT1 shaft. Care must be taken not to break the osseous hinge in osteoporotic bone. Alternatively, a strong K-wire can be used as a lever. It is important to avoid an unintentional malpositioning in the sagittal plane (dorsalization/excessive plantarization). The metatarsal head can be palpated betwenn the surgeon’s thumb and index finger before the K-wires are advanced. b Unintentional malrotation or tiliting of the metatarsal head and worsening of the DMAA or pronation can be counteracted by pulling the big toe into a slight varus and derotating while shifting and advancing the K-wires. c Depending on the surgeon’s preferences, a straight elevatorium might be favourable for large amounts of shifting as a curved tool will accomodate the medial prominence of the metatarsal head and decrease the shift