Injections are common occurrences in clinical medicine. Infrequently, there are adverse reactions. Muscle fibrosis and contractures have been reported to occur after injections in the buttocks, thigh, and upper arm. (1, 2, 3) Muscle fibrosis has been associated with fibrous contractures of the gluteal and quadriceps muscles and is likely caused by a similar mechanism. (4) Brachial neuritis has also been described as a complication of injections. (5)
Following World War II, parenteral administration of antibiotics, antipyretics, and other drugs became increasingly common. Along with the increased use of intramuscular injections came the appearance of deltoid fibrosis and contracture, as well as problems in other muscle groups. (6) The first reports of deltoid fibrosis were made in the 1960s. (7) Isolated descriptions of the condition had been documented prior to that but not in the English literature. (8)
Deltoid fibrosis is a muscle disorder marked by intramuscular fibrous bands within the substance of the deltoid muscle. (9) These bands lead to secondary contractures that can affect the function of the shoulder joint. Cosmetic disfigurement is often concomitantly noted. Scapular winging and secondary scoliosis also may be related to this condition. (10) Deltoid fibrosis is part of a spectrum of fibrotic conditions that affect both upper and lower extremities. Fibrosis is seen in people of all ages but primarily has been reported in children. The condition may involve one extremity or, in rare cases, may involve all four extremities. (9) Contractures of muscles may limit function or may cause significant social unease due to the loss of function in a limb. (9)
The incidence of deltoid fibrosis in the United States has been low. Several reports of small groups of patients with the condition have been made, but no large series have been reported. (11) The reports of large series of individuals with this condition are international. In some areas of the world, contractures that developed rarely resolved themselves. This caused significant social problems, resulting in litigation in some districts in Japan. In Taiwan, the condition has become endemic, with prevalence rates of 10 percent in some areas. (11)
The most common cause of deltoid fibrosis has been related to post-injection changes occurring in the deltoid muscle. Multiple drugs have been implicated as causing the contracture, including iron, penicillin (crystalline and oil), lincomycin, pentazocine, streptomycin, tetracycline, vitamins and antipyretics. (11)
Hepatitis B vaccine has been recommended for adults or children at high risk of hepatitis B virus (HBV) infection. (12) Various authors have described the adverse effects of Hepatitis B immunization. They are usually minor and include pain at the injection site, headache, transient fatigue, fever, and arthralgias. (13, 14, 15, 16) Some authors have described unusual conditions occurring after hepatitis B immunization such as occlusion of the central retinal vein, (17, 18) uveitis, (19) lichen ruber planus, (20) erythema multiforme, (21) nephritic syndrome, (22) acute cerebellar ataxia, (23) central nervous system demyelinization, (24) and transverse myelitis. (25) Because three cases of vasculitis have been reported after immunization with recombinant hepatitis...