We assessed the short- to mid-term survival of metallic press-fit radial head prostheses in patients with radial head fractures and acute traumatic instability of the elbow.

The medical records of 42 patients (16 males, 26 females) with a mean age of 56 years (23 to 85) with acute unstable elbow injuries, including a fracture of the radial head requiring metallic replacement of the radial head, were reviewed retrospectively. Survival of the prosthesis was assessed from the radiographs of 37 patients after a mean follow-up of 50 months (12 to 107). The functional results of 31 patients were assessed using range-of-movement, Mayo elbow performance score (MEPS), Disabilities of the Arm, Shoulder and Hand (DASH) score and the RAND 36-item health survey.

At the most recent follow-up 25 prostheses were still well fixed, nine had been removed because of loosening, and three remained implanted but were loose. The mean time from implantation to loosening was 11 months (2 to 24). Radiolucent lines that developed around the prosthesis before removal were mild in three patients, moderate in one and severe in five. Range of movement parameters and mass grip strength were significantly lower in the affected elbow than in the unaffected side. The mean MEPS score was 86 (40 to 100) and the mean DASH score was 23 (0 to 81). According to RAND-36 scores, patients had more pain and lower physical function scores than normal population values.

Loosening of press-fit radial head prostheses is common, occurs early, often leads to severe osteolysis of the proximal radius, and commonly requires removal of the prosthesis.

The use of passive stretching of the elbow after arthrolysis is controversial. We report the results of open arthrolysis in 81 patients. Prospectively collected outcome data with a minimum follow-up of one year were analysed. All patients had sustained an intra-articular fracture initially and all procedures were performed by the same surgeon under continuous brachial plexus block anaesthesia and with continuous passive movement (CPM) used post-operatively for two to three days. CPM was used to maintain the movement achieved during surgery and passive stretching was not used at any time. A senior physiotherapist assessed all the patients at regular intervals. The mean range of movement (ROM) improved from 69° to 109° and the function and pain of the upper limb improved from 32 to 16 and from 20 to 10, as assessed by the Disabilities of the Arm Shoulder and Hand score and a visual analogue scale, respectively. The greatest improvement was obtained in the stiffest elbows: nine patients with a pre-operative ROM < 30° achieved a mean post-operative ROM of 92° (55° to 125°). This study demonstrates that in patients with a stiff elbow after injury, good results may be obtained after open elbow arthrolysis without using passive stretching during rehabilitation.

There is little information available at present regarding the mechanisms of failure of modern metallic radial head implants. Between 1998 and 2008, 44 consecutive patients (47 elbows) underwent removal of a failed metallic radial head replacement. In 13 patients (13 elbows) the initial operation had been undertaken within one week of a fracture of the radial head, at one to six weeks in seven patients (seven elbows) and more than six weeks (mean of 2.5 years (2 to 65 months)) in 22 patients (25 elbows). In the remaining two elbows the replacement was inserted for non-traumatic reasons. The most common indication for further surgery was painful loosening (31 elbows). Revision was undertaken for stiffness in 18 elbows, instability in nine, and deep infection in two. There were signs of over-lengthening of the radius in 11 elbows. Degenerative changes were found in all but one. Only three loose implants had been fixed with cement. Instability was not identified in any of the bipolar implants

The lateral ligament complex is the primary constraint to posterolateral rotatory laxity of the elbow, and if it is disrupted during surgery, posterolateral instability may ensue. The Wrightington approach to the head of the radius involves osteotomising the ulnar insertion of this ligament, rather than incising through it as in the classic posterolateral (Kocher) approach. In this biomechanical study of 17 human cadaver elbows, we demonstrate that the surgical approach to the head can influence posterolateral laxity, with the Wrightington approach producing less posterolateral rotatory laxity than the posterolateral approach.