Activated osteoarthritis is a far more common cause of acute inflammation and pain in the joint. While it is also often associated with disability and a protective posture, those suffering from it usually do not experience fever, fatigue and tachycardia.
Bacterial infections can strike any joint in the body, including the hip joint. The bacteria that cause septic arthritis may enter the hip joint via the bloodstream or via a contaminated needle (even one being used to treat the hip joint). It is fortunate that such bacterial or suppurative infections are rare because they are usually accompanied by excruciating pain in the groin, pain upon moving the hip and serious general symptoms, including fever, fatigue and increased heart rate. They can also be extremely dangerous for infants and children.
The classic signs of joint inflammation such as redness, swelling and warmth are initially missing in the case of septic arthritis of the hip because the site of the infection is deep inside the hip and covered up by relatively thick layers of soft tissue. The pain in the groin and the protective posture are therefore the only direct signs of the hip infection. This makes the task of arriving at a diagnosis considerably more difficult.
The severe pain leads to a pronounced protective posture. The hip joint is held bent and turned to the outside. Loading of the hip joint is often virtually impossible. The protective posture represents a response to the increased pressure in the hip joint that is caused by the supportive infection. The specific position allows the joint to take on a greater volume.
Septic arthritis of the hip is primarily seen in infants and small children. The bacteria enter the hip joint via the bloodstream and quickly lead to a serious illness.
The pus produced by the bacteria creates massive pressure in the hip joint. This pressure can quickly cause hip dislocation or a severe limitation of the blood flow to the cartilage. If left untreated, or if treatment is delayed, the bacteria can destroy the growth centers in the hips of infants and children, with catastrophic consequences (mutilation) for the anatomic development of the hip and leg.
Treatment
Treatment begins with the immediate aspiration of the hip joint and a laboratory analysis of the aspirated fluid. This is then followed by the administration of an antibiotic. Resting the hip may also be recommended so as to prevent dislocation.
Given that these measures often do not suffice to stop the destruction of the hip joint, surgical drainage is carried out without delay to clean the hip. This procedure significantly increases the patient's chances of healing.
Are youths and adults also at risk of contracting septic arthritis of the hip?
Septic arthritis of the hip is significantly less common in youths and adults. In contrast to infants, such infections in adults are more frequently the result of a direct infection. This means that the bacteria are less likely to enter the hip via the bloodstream. The infections typically arise in connection with injections into the hip joint or surgical procedures involving the hip. That being said, it warrants pointing out that the risk associated with hip injections is minimal.
Activated osteoarthritis is a far more common cause of acute inflammation and pain in the hip joint. Such infections develop as the body attempts to dissolve wear particles in the joint (detached bone cells and chondrocytes) with the help of mastocytes, a process that leads to an increase in fluid production and pressure in the joint. While the severity of this arthritic condition depends on the exposure of the joint to stress and the extent of the existing osteoarthritis, the symptoms may include levels of pain and disability that resemble those associated with septic arthritis, although the general symptoms, such as fever, fatigue and an increased pulse rate are missing.
