Levels of myosin heavy chain fragment in patients with tissue damage

Background. Myosin heavy chain fragments (MHC) levels are observed to be hi gher in myoskeletal injuries after surgery. MHC could be a helpful suppleme ntary tool in the study of myoskeletal injuries. Methods. Serum levels of myosin heavy chain fragments (MHC) were assessed i n orthopedic patients before operation (OBO) and after operative (OAO) repa irs and in the early phase of soft tissue injury (STI) using a radioimmunoa ssay involving monoclonal antibodies to the human beta-type MHC. Results. Mean (SD) muU/L of MHC in comparison with the control subjects (75 .3 +/-. 47.1) was higher in OAO (305.8 +/- 38.1)p <0.0001, and no significa nt changes in MHC were found in STI (67 +/- 77.5). Myoglobin was notably hi gher in OBO (81.9 +/- 95.0) compared to STI (43.9 +/- 55.9) or controls p < 0.05, but there was no further change in the protein after surgery. The mea n proportional raised level of myoglobin in OBO was > twofold, and MHC incr eased by 27%. Neither myoglobin nor MHC increased in the plasma of the STI within 24 h of injury. Conclusions. These data suggest that the release of MHC could be a helpful supplementary tool in the study of tissue damage in humans. (C) 2001 IMSS. Published by Elsevier Science Inc.