The X-Files: April 2007
By Marshall Deltoff
By Marshall Deltoff
This 69-year-old woman presented with chronic shoulder pain, and marked
restriction of shoulder abduction and circumduction. (Figure 1.)
For this column, I am presenting a brief review/overview of soft tissue calcification.
This 69-year-old woman presented with chronic shoulder pain, and marked restriction of shoulder abduction and circumduction. (Figure 1.)
Diagnosis: calcific supraspinatus tendinitis.
Discussion: Soft tissue calcification involves the deposition of calcium salts into a particular soft tissue, hardening the tissue, and typically permitting it to be visualized on a plain film radiograph.
One method of classification of soft tissue calcification is based on etiology; these three categories are dystrophic, metastatic and idiopathic.
Dystrophic calcification occurs as a result of tissue damage, degeneration, inflammation or necrosis. Atherosclerotic plaquing of the aorta is a frequently seen example of dystrophic calcification. Other examples include commonly familiar phleboliths (dystrophic calcification of thrombi within a vein), and lymph node calcification, manifesting as characteristically mottled dense nodules.
Dystrophic calcification in tendons (e.g., supraspinatus) and bursae (e.g., subacromial and trochanteric) is also quite common, and also follows a degenerative, inflammatory or necrotic (e.g., chronic post-trauma) process. Clincally, the calcification of these tissues often results in pain and limitation of joint motion. This calcification represents dystrophic hydroxyapatite depositions (HADD).
Metastatic calcification occurs due to abnormal blood levels of calcium, or abnormal phosphorus levels in growing tissue. Examples of conditions demonstrating metastatic calcification include metabolic situations such as gout, CPPD and hyperparathyroidism, certain neoplasia, and hypervitaminosis D.
Idiopathic calcification is unrelated to degeneration or to serum calcium or phosphorus levels.
Another classification is based on location. The categories are:
a) concretion: a calcified mass in a vascular lumen or hollow viscus
b) conduit wall calcification: calcific infiltration of the walls of a hollow tube structure
c) cyst wall calcification: calcific infiltration of the walls of a fluid-filled cyst
d) solid mass calcification: characterized by amorphous, whorled, “popcorn” or flecked appearances
Calcification is considered to be ossification when the calcified tissue appears as bone, with cortex and trabeculation.