It can occur in different ways, from a minor anomaly to complete absence of the radius, radial side of the carpal bones and thumb.

[1]Other possible causes are an injury to the apical ectodermal ridge during upper limb development,[2] intrauterine compression, or maternal drug use (thalidomide).

[5] A different approach is to place the metacarpal of the middle finger in line with the ulna with a fixation pin.

[2][3] A risk of centralization is that the procedure may cause injury to the ulnar physis, leading to early epiphyseal arrest of the ulna, and thereby resulting in an even shorter forearm.

[6] Prior to the actual transfer of the MTP-joint of the second toe soft-tissue distraction of the wrist is required to create enough space to place the MTP joint.

The ipsilateral second toe MTP joint, together with its metatarsal arteries, its extensor and flexor tendons and its dorsal nerves to the skin, is harvested for transfer.

The transferred toe, consisting of the metatarsal and proximal phalanx, is fixed between the physis of the ulna and the second metacarpal, or the scaphoid.

The tendons of the toe are attached to those of the radial flexor and extensors muscles of the wrist to create more stability to the MTP joint.

[9] Vilkki et al. have conducted a study on 19 forearms treated with vascularized MTP-joint transfer with a mean follow-up of 11 years which reports an ulnar length of 67% compared to the contralateral side.

[9] De Jong et al. described in a review that compared to study outcomes on centralization, Vilkki reported a smaller deviation postoperatively and a lower severity of the relapse.