Table 1 Comparison of Thiemann disease and FDAB
From: Thiemann disease and familial digital arthropathy – brachydactyly: two sides of the same coin?
Thiemann disease | Familial Digital Arthropathy and Brachydactyly (FDAB) | |
|---|---|---|
Gender | M–F ratio is 1:1.1 (9 males, 10 females, 17 different families) | M–F ratio is 1:1.1 (12 males, 13 females, 4 different families) |
Age of onset | 8 years −40 years (median age = 24 years) | First decade, earliest reported age was 10 years. |
Pattern of inheritance /genetic etiology | Autosomal dominant/ unknown | Autosomal dominant/TRPV4 variants |
Clinical features | ||
Pain | 73% (14/19), usually mild. | Prominent feature |
Swelling | 75% (15/20) | Prominent feature |
Joint movement limitation | 73% (14/20) | Present |
Symmetrical | 85% (17/20) | Prominent feature |
Radiological features | ||
Affected hand joints | 95% (19/20): PIPs are more severely affected than DIPs o PIPS 95% (19/20) o DIPs 40% (8/20) o MCPs 20% (4/20) | Constant involvement of PIPs, DIPs and MCPs. (DIPs were more severely affected than PIPs) |
Affected feet joints | 20% (4/20)- MTPs | By adulthood, all MTPs are affected |
Flattening | 35% (7/20) | Prominent feature |
Irregularities | 45% (9/20) | Prominent feature |
Short phalanges | 25% (5/20) | Prominent feature (progressive) |
Broadening | 15% (3/20) | Present |
Joint space reduction | 40% (8/20) o PIPs (8/20) o DIPs (3/20) | Present (in adulthood) |
Subchondral cysts | 5% (1/20) | Present |
Fragmentation | 35% (7/20) | Not reported |
Lateral deviation | 5% (1/20)- ulnar | Prominent feature (Radial>ulnar) |