“…Folmar et al 30 reviewed 12 flexor tendon ruptures in nonrheumatoid hands and found that all were caused by pathologic states, such as a nonunion fracture of the lunate, exostosis of the distal radius, and chronic synovitis. Other causes of intratendinous flexor tendon rupture previously described in the literature include, and are not limited to, osteoarthritis of the pisotriquetral joint, 31 nonunion fracture of the hook of the hamate, 32 lunate dislocation, 33 accessory carpal bone, 34 gouty infiltration of the flexor tendon, 35 and tumor. 36 In 1991, Kannus and Jozsa 3 evaluated tendon specimens from 5 different sites after spontaneous ruptures in 891 patients.…”