Psoitis

Psoitis (psoitis), inflammation of the m. iliopsoas. Primary P. is rarely observed, mostly in children after trauma, however even in these cases the cause of psoitis is probably blood infiltration into the muscle, which upon absorption gives symptoms of muscle inflammation. Mostly in P. the muscle is secondarily involved in the inflammatory process occurring in neighboring tissues (paranephritis, paracolitis, retroperitoneal phlegmon - see Retroperitoneal space). P. is particularly often observed in tuberculous spondylitis of the lower thoracic and upper lumbar vertebrae (see Spondylitis), tuberculosis and osteomyelitis of the ilium. In these cases the causes of P. are cold abscesses (see Spondylitis). The clinical picture of P. depends on the nature of the underlying process (hemorrhage, edema, abscess, phlegmon, cold abscess) and may manifest as severe pain in the lumbar region, swelling, elevated temperature. But especially a typical sign of P. is flexion contracture of the thigh, the degree of which depends on the nature and spread of the inflammatory process. Treatment of P. depends on the cause of the disease.