Inclusion Criteria:  patients suffering from moderate or severe hemophilia A (FVIII <5%, ≥ 12 years old) factor treatment with ADVATE© or ADYNOVI© use of myPKFiT  Exclusion Criteria:  patients suffering from other coagulopathies participants without written consent participants < 12 years old joint surgery like arthroscopy, synovectomy up to six months before study suffering from different rheumatologic diseases like M. Bechterew, Psoriasi or other local or generalized joint infections (Borreliosis, septic arthritis)