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In this literature review, the authors analyse the prognostic factors in the curative treatment of scaphoid non-unions. The main negative prognostic factors are smoking, the time elapsed since the fracture, and avascular necrosis of the proximal fragment. If the latter is present, the revascularization by a pedicle or microsurgical bone autograft is probably the treatment of choice. In non-unions without evidence of osteonecrosis, vascularized bone grafts are probably not superior to conventional bone grafts, which can presently be performed under arthroscopic control, with minimal morbidity.

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Background: Contact stresses of radial head prostheses remain a concern, potentially leading to early capitellar cartilage wear and erosion. Especially point contact or edge loading could have a detrimental effect. The purpose of this study was to compare three different types of radial head prostheses in terms of joint contact areas, in comparison to the native situation. The hypothesis was that the joint contacts are lower after monopolar arthroplasty. Methods: Seven fresh frozen cadaver upper limbs were used. Radiocapitellar contact areas of a monopolar, straight neck bipolar and a bipolar design with an angled neck were compared with each other and with the native joint. After standardized preparation, polysiloxane was injected into the loaded radiocapitellar joint to create a cast from which the joint contact area was measured. Measurements were performed at three angles of elbow flexion, and in three different forearm positions. Results: In the native elbow, contact areas were highest in supination. Elbow flexion had no significant effect on native and prosthetic joint contact areas. Contact areas were decreased for all types of arthroplasties when compared to the native joint (from 11% to 53%). There was no significant contact area difference between the three designs. However, bipolar prostheses showed a lateral subluxation in neutral forearm rotation, resulting in a significant decrease of the contact areas from pronation to neutral position. Conclusions: All types of radial head prostheses tested showed a significant decrease in radiocapitellar contact area, when compared to the native joint. Bipolar designs lead to a subluxation of the radial head, further decreasing the radiocapitellar contact.