A rare condition that is most often encountered in the dominant hand of young (20-35 years) male manual workers
First-line treatment consists of avoiding exertion of the affected hand. Surgery is considered if symptoms are not alleviated after 2 months of rest.
Diagnosis
The pathogenesis of the condition is not known. It is suspected that repeated microtraumas might have a role in the condition manifesting itself.
Symptoms are periodical and often resolve over the years. Particularly in the early stages there may also be synovitis in the wrist, which causes swelling and pain.
Initially, there is wrist pain on exertion, which later changes to rest pain. The maximal pain is felt over the lunatum.
Dorsiflexion of the wrist is restricted and painful.
Grip strength is decreased.
The condition must be kept in mind in cases where a young man complains of pain in the middle of the wrist that has lasted several weeks and there are symptoms also at rest.
X-ray usually shows signs of the disease only in the later stages.
Initially a reduction in the calcium content of the lunate bone is seen, later fragmentation and collapse (picture 1).
MRI finding is abnormal from the initial stage of the condition.
Treatment
In suspected lunatomalacia, straining of the wrist should be avoided and it is advisable to support the wrist e.g. with an orthosis fastened with Velcro tape.
If the symptoms are not completely resolved after 2 months of rest, the patient should be referred to a hand surgery unit for closer diagnosis and treatment.
The method of treatment is chosen according to the severity of the disease. The most common surgical techniques are shortening of the radius and lunate revascularization with a vascular bone graft. In more severe cases, a partial or complete wrist arthrodesis needs to be considered.
References
Viljakka T. The long-term outcome of Kienböck's disease. Helsinki: Unigrafia, 2020, Publications of the Research Institute Orton. 1455-1330 http://urn.fi/URN:ISBN:978-952-69408-1-6