Coxitis of the hip joint

Inflammation of the hip joint or arthritis can be defined as coxitis of the hip joint, where the term "coxitis" (from Latin coxae - thigh) - without specifying the location of the inflammatory process - is self-sufficient from a medical point of view. [1]

Epidemiology

Experts estimate the prevalence of coxitis at 14.2% of all arthritis; the proportion of post-traumatic inflammation of the hip joint does not exceed 5-10% of all cases, and the proportion of reactive coxitis ranges from 0.6 to 2.7 cases per 100 thousand people.

According to some reports, septic arthritis in childhood and adolescence is diagnosed in one case in 70 thousand medical visits.

Purulent coxitis in an elderly adult is detected annually in about five people per 90-100 thousand people.

Causes of the coxite

The inflammatory process in coxitis has different causes and can affect the synovial membranes and bone structures of the  hip joint . And depending on the origin, types or types of the disease are distinguished.

The result of an injury, even a long-standing severe sprain, fracture of the femoral neck or dislocation of the hip joint, is its post-traumatic inflammation - right-sided or left-sided coxitis.

When the joint is affected by Staphylococcus aureus (Staphylococcus aureus), pneumococcus (Streptococcus pneumoniae), as well as beta-hemolytic cocci (Haemophilus influenzae and Kingella kingae), infectious coxitis develops. Among the viruses involved in this type of disease, experts most often call the rubella virus (Rubella virus) and the Epstein-Barr virus; hepatitis B, C and E viruses; parvovirus B19.

With hematogenous damage to the joint by Mycobacterium tuberculosis (Mycobacterium tuberculosis), often caused by reactivation of past mycobacterial foci, tuberculous coxitis can develop - in the form of peripheral osteoarticular tuberculosis of the hip joint. [2]

Infectious etiology has septic coxitis,  septic arthritis  or acute purulent coxitis, which is streptococcal, staphylococcal, gonococcal, etc. And if there is a serous effusion in the cavity of the inflamed joint, serous coxitis is determined.

Reactive coxitis is also associated with infection -  reactive arthritis  of the hip joint or infectious-allergic coxitis, caused by an increased immune response to past urogenital or gastrointestinal diseases that are caused by a bacterial infection such as Neisseria gonorrhea, Mycoplasma hominis, Ureaplasma urealyticum, Salmonella enteritenteria,  [3] Yersinia enterocolitica, Campylobacter jejuni. In reactive arthritis, inflammation of the joints develops several weeks or months after diseases of the urogenital organs or the gastrointestinal tract. [4], 

Read more in the publication –  What Causes Reactive Arthritis?

Allergic coxitis, in which inflammation of the joints occurs as an autoimmune response of the body, is associated with the use of certain dietary proteins.

Transient or transient coxitis (toxic transient inflammation of the synovial membrane of the joint) can be diagnosed in children aged three to ten years after previous viral infections as a syndrome of acute hip pain with stiffness in the hip joint and atraumatic lameness - coxitis syndrome (also called irritable hip syndrome).

In patients with  systemic lupus erythematosus  (SLE), bilateral coxitis is associated with impaired blood supply to the tissues of the joint and the development of their avascular necrosis.

Also Read:  Causes of Joint Pain [5]

Risk factors

Risk factors for the development of coxitis are:

• hip joint injuries;
• hip dysplasia and displacement of the epiphysis of the upper thigh in infants;
• prematurity of children;
• infectious diseases in children and adolescents;
• osteonecrosis;
• osteodystrophy (Paget's disease);
• the presence of autoimmune diseases, primarily rheumatoid arthritis; [6]
• diabetes;
• overweight.

Pathogenesis

In most cases, the pathogenesis of coxitis is associated with wear and thinning of the cartilage that covers the surfaces of the bone elements of this joint.

With its tuberculous lesion, the process can be limited to the synovial membrane (with minimal destruction of the articular surface), but when the inflammation originates in the bone tissue or spreads strongly to it, the joint surfaces and epiphysis are destroyed, followed by reactive formation of osteophytes.

Viruses can enter the synovial membrane of the joints or surrounding tissues, and they are perceived by the immune system as antigens. In this case, immune cells not only attack viruses, but are also deposited in the joint in the form of so-called immune complexes, causing acute viral inflammation of the hip joint - acute coxitis.

Like reactive arthritis of any joint, reactive coxitis has an immune-mediated mechanism of development associated with the fact that bacteria and viruses entering the bloodstream induce T-lymphocyte activity, which will spread to the joint tissues. Studies have revealed the cytotoxic role of the human leukocyte antigen B27 (HLA-B27) in the pathogenesis of reactive joint inflammation: this protein of blood leukocytes can change the response of the immune system at the cellular level, making it more aggressive.

Symptoms of the coxite

Pain in the hip joint , a violation of its functions, which leads to stiffness (limited mobility) of the joint, as well as difficulty in walking are the main symptoms of coxitis.

In any case, the first signs of inflammation at an early stage of the disease are pain, often minor (with the exception of the acute form). People with hip arthritis often complain of pain in the morning when they get out of bed. At the same time, for many, after 20-30 minutes after getting up, the pain subsides.

Stiffness and pain (which may radiate to the knee) lead to complaints of difficulty getting up from a chair, going up and down stairs, and bending over; on the inability to squat and hip abduction.

As the inflammation continues to affect the joint, a Trendelenburg gait (with pelvic tilt) and the so-called antalgic gait, with limping and moving in small steps (to reduce pain), may appear; at a later stage, fixed limitation of flexion/extension and abduction/adduction of the hip may occur, causing patients to visibly limp.

With septic coxitis, the skin over the joint is hyperemic and hot, the body temperature rises to fever, there may be general weakness, headache and nausea. And in neonates and infants, the hip joint is usually held in abduction flexion and external rotation.

How hip coxitis manifests itself in children, read the publication:  Pain in the hip joint in children

Complications and consequences

Coxitis leads to the destruction of cartilage with a gradual increase in pain. And the contracture of the periarticular muscles leads to a functional or actual shortening of the limb on the side of the affected joint. Scoliosis often develops.

Complications of hip reactive arthritis include ankylosing spondylitis and inflammation of the sacroiliac joint. [7]

Reactive coxitis can lead to chronic articular, ophthalmic, and cardiac sequelae.

In the case of septic coxitis, there is a threat not only of irreversible destruction and dislocation of the joint, but also of death due to the development of sepsis: up to 15% of people die with treatment, and more than 65% without treatment.

Diagnostics of the coxite

Diagnosis of coxitis begins with a detailed history and physical examination of the patient.

Tests are given: a general and biochemical blood test, a blood test for rheumatoid factor, for C-reactive protein, for antibodies to M. Tuberculosis and other bacteria; PCR blood test for viral DNA; serum analysis for HLA-B27 antigen; general clinical analysis of synovial fluid  (obtained by aspiration of the joint) with its subsequent bacterial culture.

Instrumental diagnostics is used: x-ray and  ultrasound of the hip joints , CT and  MRI of the hip joint , scintigraphy.

According to experts, the differential diagnosis of coxitis can be difficult. For example, septic arthritis should be differentiated from acute hematogenous osteomyelitis and juvenile idiopathic arthritis, Ewing's sarcoma, and Perthes' disease.

Treatment of the coxite

With infectious coxitis of bacterial origin, the main drugs are antibiotics:  Vancomycin , as well as drugs of the cephalosporin group for injection -  Ceftriaxone ,  Ceftazidime  , etc. For tuberculous coxitis, Rifampicin is used, for septic coxitis - Flucloxacillin, Clindamycin, Amoxicillin. More information in the article -  Antibiotics for the treatment of arthrosis and arthritis of the joints .

Treatment for other types of hip arthritis is aimed at relieving symptoms and preventing chronic complications. Read more:

• Joint treatment
• Joint pain medications
• arthritis pills
• Ointment for joint pain: choose the right one

Physiotherapy treatment, including exercise therapy, is discussed in detail in the publication -  Physiotherapy for diseases of the joints .

Surgical treatment of purulent and serous coxitis is to drain the joint. In other cases, with an advanced disease that is not amenable to conservative measures, a complete replacement (prosthesis) of the hip joint may be required. [8], [9]

Prevention

The best way to prevent infectious coxitis is to avoid bacterial and viral infections by maintaining good personal hygiene, preferring protected sex, and strengthening the immune system.

Getting rid of extra pounds reduces the mechanical load on the hip and other joints of the lower extremities, which slows down the wear of articular cartilage.

Forecast

The dependence of the prognosis of coxitis of the hip joint on its etiology is obvious. Gonococcal coxitis can be completely cured, while in case of septic inflammation caused by Staphylococcus aureus, after treatment with antibiotics, the functions of the hip joint are restored in 46-50% of cases, and the rest of the patients become disabled due to functional impairment of the joint.