[Risks of serial intramuscular injections]

A recently reviewed case underlined the danger of serial intramuscular injections. More recent results about muscular response to injection treatment and its morphological, anatomical, and pathophysiological effects on muscular tissue are described. Our studies about the optimum length of the needle for intramuscular injections and the thickness measurements of tissue and fat layers in the area of the most important injection points (upper outer quadrant of Hochstetter point) were supplement by animal experiments to prove that the use of short needles might lead to subcutaneous misinjections causing acute drug-induced dermal embolism. On the other hand these animal experiments demonstrated that even correctly placed serial injections might cause severe necrosis of the deep muscular structures accompanied by a major increase in serum creatinin phosphokinase activity. With intragluteal serial injections one must think of repair-induced muscular fibrosis which led to an intragluteal implantation cyst in the case reviewed by us.