Angus Keogh Procedures – Forearm Malunion
Distal radius malunion occurs when a fracture heals with altered length, inclination, tilt or intra-articular malalignment. Patients can be variably affected by malunion, with some patients having no difficulties while others have significant functional problems and pain. When function is affected, osteotomy (breaking the bone) and correction of deformity can assist some patients.
Previously, this surgery was performed by pre-operative templating of x-rays and measuring bony cuts relative to anatomical landmarks. Recent developments in computer engineering of osteotomy surgery have vastly improved the anatomical improvements achievable with surgery. Both extra and intra-articular corrections can be made using a computer model generated from a CAT Scan of the normal contralateral limb. While this procedure is now applied to the distal radius quite routinely, other more recent applications involve malunion of the shoulder, ankle and forearm.
The procedure is as follows:
- A patient with a distal radius malunion causing pain or functional problems is identified.
- A simultaneous CAT Scan is performed of the normal and abnormal body part.
- This information is referred to computer engineers who create a 3D computer model. These models can be overlapped or merged virtually (ie on the computer), allowing direct comparison of the normal and malunited body part.
- A virtual cut in the bone is planned that allows correction of the deformity.
- A virtual plate is applied to the bone, which will hold the bone in position while healing occurs.
- A 3D printer constructs a jig system that can be applied directly to the bone during surgery. This guides the cut in the bone and also the drilling of screws for the plate.
- Once the cut in the bone is made through the jig and the drill holes are made, it is simply a matter of placing the plate on the bone and inserting the screws.
My personal experience with this system has been that of a revolution. This system can eliminate error from the correction of radial malunion and indeed many other malunions.