Scapholunate ligament injuries and how to treat them

The scapholunate ligament is one of the intrinsic ligaments of the carpus (the joint between the forearm and hand). It is located inside the wrist joint, between the scaphoid and lunate bones. It is divided into three components: dorsal, volar and intermediate.

The function of this wrist ligament is very important because it prevents the scaphoid and lunate bones from separating when the fist is firmly closed.

Injury of the scapholunate ligament of the wrist

This carpal ligament can be damaged when a person falls to the ground on the palms of the hand, or when the hand turns abruptly. Carpal ligament damage is a frequent condition treated in Traumatology. When this ligament is damaged, the symptoms are pain in the centre of the wrist when stretching it (when doing push-ups for instance). The patient will also experience a loss of strength when the elbows are extended, and they might also notice protruding wrist bones when turning it. The ligament can be injured in varying degrees, the larger the damaged area is, the greater the loss of wrist function. The extent of the damage also determines the urgency of surgical treatment.

Non-surgical treatment of the scapholunate ligament injury

Recent anatomopathological studies have shown that the scapholunate ligament has interior microscopic corpuscles called mechanoreceptors that are capable of controlling the wrist and preventing the scaphoid and the semilunar bones separating when the wrist is moving or supporting weight. This explains why patients with scapholunate ligament injury experience very little discomfort. Additionally, recent biomechanical studies of neuromuscular control of the wrist have shown that there are muscles in the forearm that can compensate for rupture of the scapholunate ligament. Many of these ligament injuries are currently treated with physiotherapy and have produced very good results.

Surgical treatment of the scapholunate ligament injury

The scapholunate ligament should be operated on in two circumstances:

• When the static or dynamic mechanics of the wrist changes

• When physiotherapy does not work

Currently, this wrist operation can be performed by arthroscopy, by open surgery or by combining both techniques. The methodology chosen will depend on the degree of ligament injury, on how the carpal bones behave mechanically and the preferences of the traumatology specialist. Wrist arthroscopy has advantages over open surgery when it is performed well and technically perfected. The patient undergoing arthroscopic surgery obtains better mobility of the wrist than the patient undergoing open surgery.

Recovery of Wrist Surgery

Regardless of the surgical technique for a scapholunate ligament injury, the patient should be aware that it can take up to three months after surgery for mobility and strength to return, and it is advised that the patient should not do contact sports until six months after the operation.