Bone and joint tuberculosis is mostly a secondary lesion, with the majority of cases secondary to respiratory tuberculosis and a few secondary to gastrointestinal and lymphatic tuberculosis. One third of the world’s population (about 2 billion) is now infected with TB; one new infection is added every second, and the WHO declared an unprecedented “global tuberculosis emergency” in 1993 and reaffirmed “urgent action to stop TB” in 1998. “The incidence of tuberculosis is still on the rise.
Bone and joint tuberculosis is one of the common clinical diseases, accounting for about 5-10% of tuberculosis patients, and the disability rate is high, among the bone and joint tuberculosis: 43.9% in the spine, 9.4% in the hip joint, 8.1% in the knee joint, and less in the ankle, shoulder, elbow and wrist joints.
I. Etiology of the disease
Tuberculosis bacteria spread from the lungs through the bloodstream and stay in the ankle joint to become infected. The causative agent of tuberculosis is Mycobacterium tuberculosis, which usually cannot directly invade the bone and joint, therefore, most of the bone and joint lesions are secondary. The pathology is divided into exudative, proliferative and case-like degenerative stages.
Second, the diagnosis is based on
1.History of tuberculosis or contact with tuberculosis patients.
2.Toxic symptoms such as low fever, night sweats, loss of appetite and wasting may be present.
3.Joint pain, swelling, and limited activity.
4.Abscesses may appear and ulcerate to form sinus tracts.
5.Blood sedimentation increases during the active period of tuberculosis.
6.X-ray film shows bone destruction, narrowing of joint space and other changes.
Clinical manifestations
1. Symptoms and signs: The onset is slow, and there is often a history of sprain. The main manifestations are swelling, pain and limping. The pain is not obvious at the beginning of simple bone tuberculosis, light at rest and heavy at exertion, and becomes severe when it is transformed into total joint tuberculosis. On examination, swelling of simple bony tuberculosis is often limited to the vicinity of the bone lesion, while swelling of synovial tuberculosis and total joint tuberculosis is seen around the ankle joint. Joint function is limited. Pain and deformity are severe, and limping is significant; sometimes walking with crutches is required.
2. On X-ray, simple synovial tuberculosis can be seen as osteoporosis and swelling of the joint capsule. In the lateral view of the ankle joint, the normal fatty translucent area is pushed away, compressed and narrowed or disappeared; when there is a lot of fluid in the joint, the joint space is widened.
Localized osteolytic destruction, frosted glass-like changes or dead bone formation are seen in simple bone tuberculosis.
In case of transformation from simple synovial to total joint tuberculosis, blurring of subchondral bone plate or destruction of marginal bone is seen. In advanced stage, joint destruction is serious and deformity or ankylosis appears.
IV. Diagnosis
Based on the patient’s history, age, symptoms, signs, X-rays and laboratory findings, the diagnosis is generally not difficult, but for simple synovial tuberculosis, sometimes synovial biopsy and bacterial examination of joint fluid are required for further diagnosis.
V. Laboratory tests.
In the active stage of the disease, the blood sedimentation is more rapid, the white blood cells are normal or slightly more, and there is often mild anemia. The positive rate of pus culture in untreated patients is about 70% for tuberculosis, and the positive rate of synovial fluid culture is about 40%. Pathological examination often reveals typical lesions.
Other auxiliary examinations.
1.X-ray examination Simple synovial tuberculosis is shown as osteoporosis and soft tissue swelling on the X-ray film. The progression to total joint tuberculosis is characterized by progressive joint space narrowing and asymmetry, and marginal bone destruction can be seen. As the lesion progresses, the bone destruction increases and the subchondral bone cortex disappears, and at a later stage, the destruction of the ankle joint becomes obvious.
2.CT examination In simple synovial tuberculosis, fluid can be seen in the joint cavity, mostly in the anterior part of the ankle joint and on both sides of the Achilles tendon at the back; simple bone tuberculosis can have osteolytic changes, dead bone formation and cold abscess near the lesion in the corresponding area.
MRI examination can detect the lesion at an early stage, showing abnormal shadows of osteoinflammatory infiltration, usually with similar changes on both sides of the joint.
Differentiation
1.Rheumatoid arthritis
2.Osteoarthritis
3.Gouty arthritis
4.Pigmented villous nodular synovitis
5.Sprain injury
6.Chronic osteomyelitis
7.Large osteoarthrosis
Seven, treatment methods
1.Systemic treatment: rest, nutrition, support, anti-TB. Anti-TB drugs: isoniazid, rifampin, streptomycin, ethambutol, pyrazinamide, etc. Adhere to the principle of “early, regular, full, moderate and combined”.
2.Local treatment: local braking to relieve pain and muscle spasm; abscess puncture, with compression symptoms and not suitable for surgery.
3.Surgical treatment: remove the lesion and consider ankle fusion if necessary.
VIII. Cure criteria
Good general condition, disappearance of local symptoms, wound healing, good weight-bearing function. X-ray shows that the joint space is clear or fused in a functional position and the lesion is healed.