Limited Joint Mobility
In Limited Joint Mobility, or cheiroarthropahy, changes in the peri-articular connective tissue result in limitations in the movement of the joints. The first sign is usually a limitation of extension in the metacarpophalangeal and proximal interphalangeal joints of the little finger. Subsequently the disease progresses to radial, distal and proximal joints. Incidentally, even larger joints such as wrist, elbow and spine get affected.
About 40% of patients with diabetes will develop LJM, versus about 4-14% in the general population. Risk factors for LJM are a high HbA1c and a long duration of diabetes. In line with this, in newly diagnosed diabetes the prevalence therefore is not different from the general prevalence. Also , a few studies have found a correlation between the presence of LJM and the occurence of retinopathy and microalbuminuria in type 1 diabetes; similarly, some have reported a correlation with coronary artery disease and cerebrovascular disease in type 2 diabetes. Finally, recent research suggests that the prevalence of LJM in adolescents with type 1 diabetes is falling, possibly as a result of improved glycaemic control.
Diagnosis and treatment
The disease is classically diagnosed by asking the patient to bring his palms together, as if in prayer, with spread fingers and the wrist in dorsoflexion ("Prayer sign'). This will immediately reveal the limitation of movement in the metacarpophalangeal and interphalangeal joints (as depicted in the classical painting by Albrecht Dürer). Because both damage to the joint capsule and to the surrounding subcutaneous connective tissue contribute to the movement limitation, it is frequently accompanied by rigidity of the skin of the dorsum of the hand and of the forearm. This can be demonstrated by an impossibility to lift the skin. LJM itself is painless and only incidentally invalidating, although it does contribute to the pathogenesis of the diabetic foot. There is no specific therapy, although exercising the joints may alleviate complaints. Improvement of glycaemic control may help retard progression.