Clarkes test is used by chiropractors to diagnose patello discomfort.
Clarke's Test for Chondromalacia Patellae (Patellofemoral Pain Syndrome)
Management of Patellofemoral Pain Syndrome | AAFP
Clark's O.N.T. spool cotton trade mark - Print shows an African American man sitting on a large spool of Clark's spool cotton thread at the edge of a stream or lake; he