Case Of the Week (COW) 16 Nov 2014
Answer:
Hydroxyapatite (HA) crystal deposition disease (HADD)
Findings:
Hypo intense foci in all sequences - Calcium Hydroxy Appatite deposits noted in the supraspinatus tendon located in the poorly vascularized critical zone a few millimeters medial to the osseous insertion.
Discussion:
CHA deposits occur in tendons, peritendinous tissues, bursae, and ligaments. CHA deposits in the supraspinatus tendon are typically located in the poorly vascularized critical zone, which is a few millimeters medial to the osseous insertion. CHA deposits in other tendons occur preferentially in hypovascular segments, supporting the hypothesis that local necrosis leads to crystal deposition. Mosely- three phases : Silent phase where the CHA is completely contained within the tendon. Radiographs will show well defined CHA deposits which represent dry granular or “cheesy” material. Second or mechanical phase - enlargement of the deposit occurs followed by impingement-like symptoms which result from CHA deposit enlargement. The deposits liquefy and cause increased intratendinous pressure and bursitis. The CHA deposits become less defined radiographically. The CHA deposits rupture either into or around the adjacent bursa.On radiographs the CHA deposits disperse into the adjacent bursa or peribursal soft tissues. Third and last phase is called adhesive periarthritis. This is a late stage that presents with general debility, pain, and limited range of motion. In the adhesive periarthritis phase, patients have adhesive bursitis, CHA deposits within the rotator cuff and intraosseous and dumbbell-like CHA deposits.
Answer:
Hydroxyapatite (HA) crystal deposition disease (HADD)
Findings:
Hypo intense foci in all sequences - Calcium Hydroxy Appatite deposits noted in the supraspinatus tendon located in the poorly vascularized critical zone a few millimeters medial to the osseous insertion.
Discussion:
CHA deposits occur in tendons, peritendinous tissues, bursae, and ligaments. CHA deposits in the supraspinatus tendon are typically located in the poorly vascularized critical zone, which is a few millimeters medial to the osseous insertion. CHA deposits in other tendons occur preferentially in hypovascular segments, supporting the hypothesis that local necrosis leads to crystal deposition. Mosely- three phases : Silent phase where the CHA is completely contained within the tendon. Radiographs will show well defined CHA deposits which represent dry granular or “cheesy” material. Second or mechanical phase - enlargement of the deposit occurs followed by impingement-like symptoms which result from CHA deposit enlargement. The deposits liquefy and cause increased intratendinous pressure and bursitis. The CHA deposits become less defined radiographically. The CHA deposits rupture either into or around the adjacent bursa.On radiographs the CHA deposits disperse into the adjacent bursa or peribursal soft tissues. Third and last phase is called adhesive periarthritis. This is a late stage that presents with general debility, pain, and limited range of motion. In the adhesive periarthritis phase, patients have adhesive bursitis, CHA deposits within the rotator cuff and intraosseous and dumbbell-like CHA deposits.