MB and rhabdomyolysis: When the basal membrane and sarcolemma of the injured muscle fibres are compromised (such as in rhabdomyolysis), the consequential result is that cytoplasmic components, such as myoglobin and creatine kinase (CK), are released from the injured muscle fibres into the blood stream (Spraker, 1993; Vanholder et al., 2000).