The callotasis lengthening technique was used to gradually lengthen the capitate after resection of the lunate in stage IIIa necrosis in 23 patients. Results of ten patients with a follow-up of at least 5 years showed rapid and sufficient callus formation in every patient regardless of age. The callotasis lengthening modification of the Graner II operation provides all advantages and avoids the major inconvenience of the traditional Graner II operation. There was no increased rate of disturbed fracture healing. Results of the DTPA-gadolinium MRI study did not show any significant impairment of vascularization within the region of the capitate bone. With the "intrinsic bone formation," contrary to every other intercarpal arthrodesis at the wrist, there is no need for an additional bone graft.