Epiphyseal enlargement occurs in -
Epiphyseal enlargement

Most common causes of epiphyseal enlargement are chronic inflammation (e.g. JRA) or chronic increase in blood flow. Causes of Epiphyseal enlargement are:-

a) Solitary (Enlargement of particular epiphysis)

Post-inflammatory (JRA, Septic arthritis)
Perthe's disease (in repair stage)
Status post hip dislocation
Hemophilia (Hemophilic arthropathy)
Turner syndrome
Klippel-trenaunay syndrome (angiohypertrophy syndrome)
Kascibach - Merritt syndrome
Beckwith - Wiedemann syndrome (Hemihypertrophy)
Trevor disease (Dysplasia epiphysealis hemimelica)

b) Generalized

Hyperthyroidism   
Acromegaly or cerebral gigantism         
Adrenogenital syndrome   iv) Rickets
Spondyloepiphyseal dysplasia
McCune-Albright syndrome
Kniest syndrome
Paget's disease
Sheurmann's disease
Epiphyseal dysplasia
Hemophilia