Anatomy
The bones of the wrist consist of 8 carpal bones (ossa carpi), which together with the two forearm bones, the ulna and radius, form the wrist. There are many ligaments that hold the carpal and forearm bones together and are important for the stability and function of the wrist.
The two carpal bones scaphoideum (S) and lunate (L) are held together by a strong ligament (scapholunate interosseous ligament), and the lunate (L) and triquetrum (T) are also held together by a ligament (lunotriquetral ligament). There are many other ligaments between the carpal bones, with the ligaments (midcarpal ligaments) between the two rows of carpal bones (blue arrow in the figure) being particularly important ( Wessel LE, Wolfe SW. 2023).
Cause of the problem
Heavy (falls) and possibly repeated stresses on the wrist and thus the carpal bones can lead to rupture of the ligaments. Ruptures are relatively rare, but serious injuries. Ligament injuries in the wrist can lead to instability, osteoarthritis and fluid-filled deposits (ganglia).
Symptoms
Acute rupture of the scapholunate, lunotriquetral and midcarpal ligament tears cause pressure pain in relation to the injured ligament(s).
Examination
Suspicion is raised by clinical examination of someone who has experienced sudden pain in the wrist. The pain is localised to the ligaments and often worsens if the wrist and metacarpals are stress tested. Dynamic ultrasound scanning can be used to see the distance between the carpal bones increase if the ligaments are torn (possibly in relation to the opposite side), but the diagnosis is often first made with arthroscopic surgery (arthroscopy), which is best for assessing the ligaments between the bones.
X-rays and especially CT scans are usually indicated to rule out fractures or displacements of the carpal bones. Significant delay in diagnosis can result in a poorer prognosis.
Treatment
Lunotriquetral and midcarpal ligament ruptures are usually treated with relief from pain-inducing activity and bandaging. Maintaining muscle strength and cardio training can continue unchanged.
If the bones are displaced, surgery is usually advised. It can take months (half a year) before it is possible to return to sport. For partial tears of the scapholunate ligament, conservative treatment gives good results (Karaalioglu B, et al. 2023), but in cases of total tears, surgery is advised in an attempt to restore a stable ligament. Wrist motion restriction is a common secondary injury, which can be problematic in throwing sports. Delayed diagnosis and treatment can result in permanent pain and require reoperation.
Long-term (‘chronic’) strain pain despite offloading can be reduced by medical treatment in the form of ultrasound-guided injection of adrenal cortex hormone into the joint at the ruptured ligament(s). If relief and medical treatment are unsuccessful, surgical treatment may be indicated (Amer KM, et al. 2023).
Rehabilitation
Usually, cardio training in the form of cycling and running can be continued, as well as rehabilitation according to the guidelines under rehabilitation in general. Gentle range of motion exercises of the hand muscles ensure maintenance of mobility and can be combined with slowly increasing strength training of the muscles around the wrist within the pain threshold.
If surgery has been performed, there are specific precautions that the operator should clarify.
Complications
If no progress is made, consider whether the diagnosis is correct, e.g. total rupture of multiple ligaments, fractures in the bones around the wrist.
