22-year old lady was noted to have painful cramps and spasms affecting both hands. Her calcium level was found to be 7.2 mg/dl (normal: 9-10.5 mg/dl). Pictures of her hands are shown above. A diagnosis of hypocalcemic tetany was made.
In carpopedal spasm, both hands and feet are affected. In hands, there is flexion at wrist and metacarpo-phalangeal joints and extension at inter-phalangeal joints. Thumb and other fingers are adducted. These findings can be seen in above pictures.
Once you see these clinical features, hypocalcemia should be suspected. Once hypocalcemia is confirmed, treatment with calcium gluconate injections rapidly improves the condition.
Other clinical tests of latent tetany due to hypocalcemia are Chvostek’s sign and Trousseau sign. For further reading on this topic, visit the following link: http://www.cmaj.ca/content/183/8/E498