Pyomyositis is a bacterial infection of the skeletal muscles, characterized by the formation of pus-filled abscesses within the muscle tissue. While pyomyositis can affect any skeletal muscle in the body, it most commonly occurs in the large muscle groups, such as the thighs, buttocks, or upper arms.
The condition typically arises from a bacterial infection, often caused by Staphylococcus aureus, which enters the muscle tissue through small breaks in the skin or via the bloodstream. Risk factors for pyomyositis include immunocompromised states, diabetes, trauma, and recent surgery.
Symptoms of pyomyositis may include localized muscle pain, swelling, warmth, and redness, as well as fever and general malaise. As the infection progresses, an abscess may form within the affected muscle, leading to increased pain and swelling.
Diagnosis of pyomyositis often involves a combination of clinical evaluation, imaging studies such as MRI or ultrasound to visualize the abscess, and sometimes aspiration of fluid from the abscess for laboratory analysis.
Treatment typically involves antibiotics to target the underlying bacterial infection, along with drainage of the abscess either through needle aspiration or surgical incision and drainage. In severe cases, hospitalization and intravenous antibiotics may be necessary.
Prompt diagnosis and treatment of pyomyositis are important to prevent complications such as spreading of the infection to nearby tissues, bloodstream infection (sepsis), or long-term muscle damage.
Septic arthritis of the spinal facet joints is increasingly recognized in the era of magnetic resonance imaging, but its epidemiology, clinical features, management, and prognosis are ill-defined.
Ross et al. reviewed 101 previously published cases and report 16 cases occurring between 2006 and 2018.
Most patients presented with fever (60%) and back or neck pain (86%). Radiation into the hip, buttock, or limb was present in 34%. The lumbosacral vertebral segments were involved in 78% of cases. Most cases (64%) were due to Staphylococcus aureus. Bacteremia was present in 66% and paraspinal muscle abscesses in 54%. While epidural abscesses were present in 56%, neurologic complications were seen in only 9%, likely because most abscesses arose below the conus medullaris. Neurologic complications were more common with cervical or thoracic involvement than lumbosacral (32% vs 2%, P < .0001). Extraspinal infection, such as endocarditis, was identified in only 22% of cases. An overall 98% of patients survived, with only 5% having neurologic sequelae.
Septic arthritis of the facet joint is a distinct clinical syndrome typically involving the lumbar spine and is frequently associated with bacteremia, posterior epidural abscesses, and paraspinal pyomyositis. Neurologic outcomes are usually good with medical management alone 1)