Knight and colleagues tested a metal radial head prosthesis in cadaver elbows and reviewed its results as primary replacement for comminuted radial head fractures.
Review of 31 of 36 consecutive patients (mean age 57 at follow‑up) a mean 4.5 years (2 to 8) after primary uncemented Vitallium replacement, plus cadaver compression tests.
Key Findings
In cadaver tests, the radius migrated proximally 2.6 times as far after radial head excision as when intact. The metal head resisted this, while silicone still allowed 2.3 times normal migration.
No prosthesis dislocated, fractured or became infected, and no elbow redislocated. Two implants were removed for painful loosening.
At review, 24 of 31 patients had little or no elbow pain and 6 ached laterally only with activity.
Restricted motion or pain on activity tracked injury severity, by the authors' account. In this series 68% had a dislocation, an ulnar fracture or both.
Radiolucent lines surrounded 7 prostheses but did not appear progressive. Distal radioulnar subluxation was found in 2 patients, of 2 mm and 10 mm, and the 10 mm case had had the implant removed.
The authors did not show a benefit for isolated fractures. If the elbow is stable in flexion after excision, they and earlier reports suggest replacement adds nothing.
Board pearl
In the senior author's experience, late radial head insertion caused malarticulation and capitellar erosion. The authors therefore urge early replacement, before soft‑tissue contracture, though this series did not test timing.
Authors' conclusion
The prosthesis is recommended for use as a spacer to stabilise the elbow after severe injuries while the soft tissues heal.
Knight and colleagues tested a metal radial head prosthesis in cadaver elbows and reviewed its results as primary replacement for comminuted radial head fractures.
Review of 31 of 36 consecutive patients (mean age 57 at follow‑up) a mean 4.5 years (2 to 8) after primary uncemented Vitallium replacement, plus cadaver compression tests.
Key Findings
In cadaver tests, the radius migrated proximally 2.6 times as far after radial head excision as when intact. The metal head resisted this, while silicone still allowed 2.3 times normal migration.
No prosthesis dislocated, fractured or became infected, and no elbow redislocated. Two implants were removed for painful loosening.
At review, 24 of 31 patients had little or no elbow pain and 6 ached laterally only with activity.
Restricted motion or pain on activity tracked injury severity, by the authors' account. In this series 68% had a dislocation, an ulnar fracture or both.
Radiolucent lines surrounded 7 prostheses but did not appear progressive. Distal radioulnar subluxation was found in 2 patients, of 2 mm and 10 mm, and the 10 mm case had had the implant removed.
The authors did not show a benefit for isolated fractures. If the elbow is stable in flexion after excision, they and earlier reports suggest replacement adds nothing.
Board pearl
In the senior author's experience, late radial head insertion caused malarticulation and capitellar erosion. The authors therefore urge early replacement, before soft‑tissue contracture, though this series did not test timing.
Authors' conclusion
The prosthesis is recommended for use as a spacer to stabilise the elbow after severe injuries while the soft tissues heal.