From the Research
The posterior interosseous nerve is at risk of injury if the annular ligament is incised very close to the ulna. This nerve, which is a branch of the radial nerve, passes close to the proximal radioulnar joint and wraps around the neck of the radius. When surgically approaching the annular ligament, incisions made too close to the ulna can damage this nerve as it traverses this region. The posterior interosseous nerve supplies motor function to the extensor muscles of the forearm, so injury can result in weakness or paralysis of wrist and finger extension, known as posterior interosseous nerve syndrome. To avoid this complication, surgeons typically approach the annular ligament from the radial side or use careful dissection techniques when operating in this area. Understanding this anatomical relationship is crucial for procedures involving the proximal radioulnar joint, such as treatment of nursemaid's elbow or annular ligament reconstruction, as highlighted in a recent study 1.
Some key points to consider when evaluating the risk of injury to the posterior interosseous nerve include:
- The proximity of the nerve to the ulna and the annular ligament
- The potential for damage to the nerve during surgical approaches to the annular ligament
- The importance of careful dissection techniques and approaching the annular ligament from the radial side to minimize the risk of injury
- The potential consequences of injury to the posterior interosseous nerve, including weakness or paralysis of wrist and finger extension. A recent study 1 compared different methods for stabilizing the radial head and found that annular ligament repair was the most effective at reducing anterior radial subluxation, but also noted the importance of careful rehabilitation to minimize residual instability. Another study 2 proposed a ligamentoplasty to stabilize the radial head using a single graft, and found that the gracilis tendon was more suitable than the palmaris longus due to its constant presence and length. However, the most recent and highest quality study 1 provides the most relevant evidence for this question, and highlights the importance of careful technique and consideration of the anatomical relationships in the region to minimize the risk of injury to the posterior interosseous nerve.
In terms of specific techniques for avoiding injury to the posterior interosseous nerve, some options include:
- Approaching the annular ligament from the radial side
- Using careful dissection techniques to minimize damage to surrounding tissues
- Avoiding incisions that are too close to the ulna
- Considering alternative methods for stabilizing the radial head, such as ligamentoplasty or annular ligament repair. Overall, the key to minimizing the risk of injury to the posterior interosseous nerve is a thorough understanding of the anatomical relationships in the region, combined with careful technique and attention to detail during surgical procedures.