Resurgence of Tuberculosis: Bone and Joint Scenario1

The prevalence of tuberculosis which was supposed to be contained with better standard of health and education in developing countries, has been rising worldwide including Western countries.⁷⁵ Before 1940 mortality and morbidity was very high. After 1950 disease was controlled but it has now reappeared. In USA morbidity had increased by 14% between 1985 to 1993.⁷⁶ WHO report of 1996 states that nearly three million people died of tuberculosis in 1995 in the world.⁷⁵ This surpasses the worst epidemic of 1900. In India tuberculosis claims about 1300 lives everyday. There are two million new cases and 500 deaths a year.⁴⁹ Much of this increase has been related to pulmonary tuberculosis. It has also been associated with a concomitant rise in the number of adults and children who have tubercular musculoskeletal involvement. At the end of 20th century with so many effective drugs available still we are faced with serious threat of the battle going out of hand. The factors which have contributed to the rising incidence of tuberculosis are:

Tuberculosis is an ancient disease and spinal tuberculosis was seen in egyptian mummys as early as 3400 BC. The first description of tuberculous spondylitis was written in1500 and 700 BC. The milestones are, Tubercle Bacilli was discovered in 1882, X-ray in 1895 and BCG in 1921.³¹ These developments made diagnosis possible but treatment was difficult. The historical course can be roughly divided in three eras: (a) ancient times when Hippocrates said, “their treatment was a waste of time”, (b) preantibiotic days when the sanatorium line of treatment was practised which had a 60% mortality and (c) post-antibiotic era which started with introduction of streptomycin in 1940. Thereafter, it looked as if the disease will be eradicated. But somewhere the predictions went wrong and the steadily declining incidence of tuberculosis has reversed since 1985. The 2003 WHO report shows estimated 88 million new cases every year with 52000 deaths per week.³ It is now going to be a long battle.

The common textbook teaching of a tuberculosis lesion starting with typical tubercle consisting of central caseating area surrounded by epithelioid cells and giant cells, is only partly true of bone and joint tuberculosis. To begin with bone and joint tuberculosis is always secondary to a primary lesion which may be anywhere, common being lungs, lymph glands and kidneys. However, only 1/3rd of skeletal tuberculosis patients show pulmonary tuberculosis.⁷⁶ The most surprising fact which is sometimes ignored is that the primary focus can remain hidden and this does not rule out the diagnosis of tuberculosis. According to Saxena et al 73% of cases no primary was detected.⁵⁹ In skeletal tuberculosis bacterial population is low in comparison to pulmonary tuberculosis. The rate of bacterial population between pulmonary and skeletal being 100 : 1 their metabolism is low and can remain dormant for long-time, slowly and intermittently metabolising. This is explained by difference in the nature of skeletal tissue and pulmonary tissue. Further, mechanical attrition and high incidence of residual physical disability after healing differentiates it from pulmonary and other extrapulmonary lesion. Constitutional symptoms are also less in skeletal tuberculosis. Unlike pulmonary tuberculosis, extrapulmonary tuberculosis is more common in children than in adult.⁷⁶ However, this pattern is changing due to increasing 3elderly population and immune compromised individuals. Previously, proportion was 50 : 50 whereas now it is now 20 : 80. Another factor which changes the behaviour of the disease is immuno compromised status of the patient. This may be due to HIV or presence of any other debiliating condition, i.e. malnutrition, diabetes, etc. Though the process errodes the normal bone easily, it attacks the cartilage only indirectly causing subchondral erosion and destroys the cartilage quite late. Further involvement of joints not only affects the articular ends but also spreads to synonvium. Sometimes, the entire synovium may appear involved but biopsy report may show chronic inflammatory process if correct area is not selected. On the other hand sometimes the infection may start in the synovium and remain confined for some time before spreading to articular ends or surrounding tissues. Caseation and necrosis of the synovium and the joint capsule are rare.⁵

The structures involved in musculoskeletal tuberculosis are:

Diagnosis of skeletal tuebrculosis is not difficult when the classical signs of pain, tenderness, muscle spasm, limitation of movement and deformity are present, let alone presence of sinus and abscess. But diagnosis at this stage is not helpful as with treatment the disease may heal but will leave considerable residual disability in the form of deformity, shortening, etc. Hence, it is very important to recognise the diseases very early to give the patient a disability free life.

Laboratory investigations are not always confirmatory, they only supplement to the clinical diagnosis. Specially in early stage of the disease, the findings may be inconclusive, X-ray changes may come late, imaging may not be available and still diagnosis has to be made to treat the disease and avoid morbidity. Sometimes diagnosis has to be presumptive (Fig. 1.2).

It has been observed that the ESR can remain high even after healing of the lesion.

It has been stated that montoux test isalways positive. But there has been number of reports that montoux skin test can be negative⁵² in the presence of disease. Except in children it is of little value. In adults it depends on the exposure to tuberculosis.

Plain radiography remains the cornerstone of diagnosis. Conventional radiography do not show changes until disease has been present for 2-8 weeks.¹ However, for early diagnosis one can not wait till classical signs of destruction and loss of joint space appears. Common findings that should arouse suspicion of joint involvement includes periarticular osteopenia, soft tissue shadow with erosion of articular margin and joint space narrowing. Joint space can be preserved for considerable time for enough destruction of cartilage to occur to cause radiological narrowing. Cysts adjacent to joint surface, enlargement of epiphysis in children should arouse suspicion. Phemister's triad of periarticular osteoporosis, marginal erosion and narrowing of joint space is the radiological feature of osteoarticular tuberculosis. Tuberculous osteo myeltis has to be differentiated from pyogenic one. Sometimes, it becomes difficult specially after inadequate treatment. However, one has to look for periosteal new bone formation and sclerosis of margins in pyogenic lesion.7

CT scan and MRI have enabled the clinician to diagnose the disease at an earlier stage than is possible by conventional methods. It has also helped in planning the surgical treatment.

While CT provides sufficient information regarding the bony elements it does not provide that much information regarding soft tissues. Tissue delineation being better in MRI it demonstrates the pathological tissues, i.e. granulation tissue, pus or only fibrosis. Furtehr, MRI produces pictures in both sagittal and coronal planes. Spinal cord is visualised better. MRI can be useful in warning the surgeon the need for a more extended approach and can give an accurate idea of the size of the strut graft needed (Fig. 1.3).8

Aspirated material from peripheral joints or cold abscess is not of much help. Cytology shows more of lymphocytes. Though ultimate diagnosis of tuberculosis is culture and isolation of bacteria, but it is time taking and needs special facilities. It is rarely done in skeletal tuberculosis. Regional lymphnode biopsy is not always positive. Besides, it is only possible in peripheral joints with enlarged glands which may not be always present.

ELISA for tuberculosis has a reported sensitivity of 60 to 80% only.⁷⁶ These tests are also positive in other condition and may some times be negative in the presence of the disease. Hence, do not rule out tuberculosis if it is negative while other features are present. Myco Dot, ELISA, IgG, IgG(M), IgG(A) are based on detecting antibodies to mycobaterial antigen. IgG is positive in older or chronic infection. IgG(m) in current infection, IgG(A) indicates active tuberculosis lesion. All factors has to be positive to diagnose tuberculosis. The specificity of these tests are 50 to 75%, Mycodot has no value in detection of tuberculosis. The more recent test PCR is based on DNA amplification 9of M tuberculosis, which is highly sensitive. Compared to culture it has predicatability of 83.5 and 94% respectively.⁵⁵ Sareen et al reported sensitivity of 73.17% and specificity of 100%. The result is available in 36-48 hours. They concluded superiority of PCR over other dagnostic tests.⁵⁸ Van der speel reported sensitivity and specificity for PCR using histology as gold standard were 78.6% and 87.1% respectively with negative predictive value of 73.3% and 90%.⁷³ Titos and Alexei reported PCR of tissue arthroscopicaly obtained from affected joint and found positive result in all tissues.⁶⁵ It appears from above reports that PCR has the best predictive value.

Over the years treatment of bone and joint tuberculosis has undergone radical change from the days of Hugh Owen Thomas who advocated “Rest, enforced, prolonged and uninterrupted”. Effective treatment started with advent of streptomycin, PAS and isoniazide during a period from 1944 to 1951. These first line drugs were later supplemented by Rifampicin, Ethambutol and Pyrazinamide. The drug cover encouraged surgeons to carry out excisional surgery so that drugs can reach the diseased area and enhance healing.^15,47,77 However, after sometime there was reassessment and questions were raised whether surgery and immobilisation were at all necessary.²⁹ Later immobilisation was used very sparingly. This led to MRC studies^35-39 to provide answer and settle this controversy. These studies were mainly on treatment of spinal tuberculosis but it has relevance to the treatment of other forms of skeletal tuberculosis as well. The treatment of skeletal tuberculosis is primarily medical, as stated previously and operative intervention is an adjunct to appropriate antituberculous chemotherapy.

The selection of drugs and their duration has changed over the years. The most patent bacteriocidal drug is isoniazid. However monotherapy with Isoniazid quickly results in resistance of bacteria. Therefore, a combination of drugs is necessary. Regarding duration, prolonged drug therapy is necessary to eliminate or sterilise the so called persistent bacilli. Rifampicin and Pyrazinamide are the most effective sterilising drugs and they are specially effective against bacilli that are dormant and undergo periodic bursts of activity. Ethambutol is bacteriostatic. Streptomycin is bacteriocidal but has to be given parenterally and produces adverse effect. Quinolones have in vitro activity but resistance quickly develops and have limited use. The revised 10National Tuberculosis Control Programmes recommends administration of drugs 3 times a week regeme¹¹ but this is not suitable for treatment of skeletal tuberculosis. The current recommendation for drug treatment of adults who have skeletal tuberculosis is Isoniazid 5 mg/kg body weight, Rifampicin 10 mg/kg body weight, Pyrizinamide 20-30 mg/kg body weight and Ethambutol 15-25 mg/kg body weight a day in the initial phase which is about 2 months following which 3 drugs, i.e. Isoniazid, Rifampicin and Ethambutol to be continued.

The optimum duration of treatment for non resistant patients has been an issue of considerable debate and much of it relates to the treatment of pulmonary tuberculosis. Short course regimens may not be suitable to skeletal tuberculosis Watts and Lifeso⁷⁶ advocate minimum of twelvemonths. Mittal, et al⁴² prescribe 9-18 months, Ingalhalikar²³ mention 9 to 12 months. However, Parthasarathy, et al⁴⁸ advocate ambulant chemotherapy for 6 months. Most of these recommendations are for spinal tuberculosis. It appears there is a lack of study to standardise the duration of drug regime in skeletal tuberculosis. Is the duration same for spinal as well as other parts of skeleton? Is the duration same in the presence of paraplegic, sinus and other complications? Does the so called DOTs regime affect the prognosis of extra pulmonary forms specially skeletal tuberculosis if they are concurrently present ? These problems await an answer. However, a drug regime of minimum 9 months should be on the safe side. Sometimes in rapidly deteriorating paraplegic or miliary tuberculosis a short steroid course can be added to reduce cord oedema.11

Immobilisation has been a part of treatment of tuberculosis of bone and joints since the time of H.O. Thomas. Even after the use of antitubercular drugs and excisional surgery, prolonged immobilisation was practised. This was based on the belief that immobilisation will help achieve fibrous or bony union early. However, with early diagnosis and aims of achieving mobile joints, use of immobilisation diminished. Now use of immobilisation is restricted to:

Even long before the advent of antitubercular drugs, surgeons had tried to excise the tubercular focus with the hope of eradicating the disease with disastrous results. It led to a strictly conservative attitude towards surgical treatment to the exent that Dickson¹⁴ stated “Even introducing a drainage tube into tubercular area presaged the patients death warrant”. The introduction of antitubercular drugs led to reconsideration of this attitude to the effect that the pendulum swung to the other extreme and some surgeons believed that without excisional surgery drugs will not reach the site.^54,64 Mukhopadhya⁴⁵ stated that excision will provide two benefits: (i) full concentration of drugs at the vascularised site, (ii) a major obstacle to improve the resistance was removed. However, with experience enthusiasm for surgery declined. Tuli⁷¹ advocated a “midpath regime”. Though the debate still persists but it has been settled to a large exent by a series of MRC studies.

Indication of surgery may be grouped as:

Resistance to antitubercular drugs is increasing and is one of the main cause of concern. The incidence at present is 7 to 15%.⁶⁹ The incidence of resistance to different drugs is different. However, multidrugs resistance (MDR) is defined as resistance of the organisms to two drugs, i.e. Isoniazid and Rifampicin. The drug resistance may be: (a) resistance among new cases (Primary), (b) resistance among previously treated cases (acquired).

The causes of multiple drug resistance are:

Unlike Pulmonary tuberculosis detection of resistance to skeletal tuberculosis is difficult and time taking. Conventional methods of diagnosing resistance by testing drug sensitivity is time taking, costly and not available everywhere. Besides unlike pulmonary tuberculosis availability of sample of bacteria for testing is difficult in skeletal tuberculosis. Hence, by necessity the diagnosis of resistance has to be based on clinical findings and imaging. Failure to show adequate improvement of general and local symptoms, non healing of sinuses and abscesses, non healing of surgical wounds, and appearance of additional focus after adequate treatment for 4 to 5 months should be taken as development of resistance, Signs in X-ray and imaging can supplement the diagnosis.

By the time resistance is suspected, four drugs have already been tried. Six drugs should be administered with addition of streptomycin and PAS or thiocetazone. However, patient should be monitored for toxic symptoms. If the patient does not respond, other 2nd line drugs can be used as suggested by Tuli.⁶⁹ The treatment should be continued for a prolonged period about 24 months.⁶⁶ But at this stage it is time to consult a specialist and administer these drugs after hospitalisation as they are toxic. Corticosteroids can play a role in supplementing the effect of the drugs. Recently there has been reports of using immunomodulation in dealing with resistant patients. Tuli⁶⁹ advocated use of a combination of Levamisole, BCG and DPT in 14conjunction with other antitubercular drugs. However, this has not been supported by study of a large series. Arora studied the interlukin profiles of tuberculous patients treated with ATT only and those treated with ATT plus immunomodalatory drugs. Addition of immunomodulatory drugs shortens the duration as well as improves clinical response.³ Sometimes, radical debridement helps in controlling the disease.

The role of surgical treatment in tuberculosis of spine has passed through various stages over the years. Begining from the days of Hibbs and Albec in early 19th century, Girdlestone, Roaf and Mukhopadhya in 1950's, and Hodgson in 1960's, it has its advocates and critics.^{2,16,22,47,54} Several Medical council reports have played a role in settling some of the controversies. It has been the conventional teaching that antitubercular drugs do not the reach the tubercular diseased area in effective concentration, hence debridement. However, now there are number of reports that modern antitubercular drugs reach the lesion in effective concentration.⁴³ The excision and anterior fusion was recommended by the Hong Kong group³⁵ with the aim that there will be rapid bony union and arrest of kyphotic deformity. But studies in Chennai^48,53 did not coroborate these findings. The indications have been narrowed down to only a few condition involving complications of tuberculosis of spine. The simple procedures like anterolateral decompression and Costotransversectomy have aimed at decompressing spine without dealing with the diseased lesion in the vertebral body. Inspite of various aggressive procedures to excise diseased tissue from vertebral body, anterolateral decompression and costotransversectomy remains the most practised procedure for Pott's paraplegia in many centres in India. MRI can show the site of the disease in the thoracic vertebra, i.e. anterior, posterior, combination of anterior and posterior, and posterior. Basing on MRI findings Mehta⁴⁰ classified tuberculosis of thoracic spine into four groups and adopted separate surgical treatment for each group:

Tuberculosis of skeletal system leads to deformity in various joints including spine. In the spinal column, Kyphosis of various degrees is a common type of deformity. The tubercular infection starts in the anterior part of the body and as the anterior part of the body gets destroyed the spinal column slowly bends forward producing angular kyphotic deformity. It is more pronounced in the thoracic and thorcolumbar region as there is existing anterior curvature. It is less pronounced in cervical and lower lumbar region. Besides these, the other factors which influence the development and degree of kyphosis are:

Bone and joint tuberculosis constitutes 1-3% of all tuberculosis patients and spine accounts for 75% of them.⁴² Tuberculosis of peripheral joints and tuberculous osteomyelitis constitute, the rest 25%. There has been no controlled study regarding the incidence of tuberculosis of peripheral joints covering all the Indian centres. The textbooks describe incidence of hip, knee and wrist in descending order. However, Moon et al have reported incidence of peripheral joints 40.9% and Hip 16.3% knee 10%, ankle and SI joint 3.5% and 3.1% respectively.⁴⁴ Mehta reports Hip 13.6%, Knee 9.8%, elbow and ankle 21% and 20% respectively.⁴¹ Mittal et al report about 10% of osteoarticular tuberculosis affects the foot.⁴² Tuli reporting on data collected during 1965 to 67 states that spine 4.1%, hip 7.5%, knee 8.3% which is in agreement with figures reported by previous authors. The incidence regarding other joints varies between different authors. The incidence of SI joint tuberculosis in BHU. Hospital series⁷¹ is higher than other reported figures. It is placed next in sequence to knee joints. However, all these figures relate to pre 1995 period. A coordinated study involving different centres in India will reflect the real situation.

Hip and knee are the two large weight bearing joints in the body. Though their anatomy differs but as far as tuberculous infection is concerned there are some similarities. In both, there is a large synovial cavity, articular cartilage, subchondral area and adjoining metaphysis. The infection can start in any of these structures though their site and spread differ in both the joints. While the infection in the hip may 18start in acctabulum, epiphysis, metaphysis and trochanter, the onset of infection in synovium of the hip is rare. Where as in the knee joint infection starts in synovium and may remain confined to synovial cavity for a prolonged period. In hip joint the metaphysis being intracapsular it is involved rapidly which does not happen in knee joint. Pain and limp is more marked in hip disease than in the knee, whereas knee joint the disease being synovial to begin with swelling is more marked than pain in the early stage.

Tuberculosis of hip joint is about 15% of all skeletal tuberculosis.³⁴ Presently age group has become diverse. Though it is common in children, more and more from older age group are presenting with the disease.⁴ The presenting symptom being pain and limp in a child, it can mimic many other conditions. Diagnosis is easy once the characteristic symptoms with limitation of movements or deformity appears. Since tubercular hip disease end up with significant morbidity inspite of the disease being cured, it becomes the responsibility of the orthopaedic surgeon to arrive at an early diagnosis. Early diagnosis of tuberculosis of the hip joint and its effective treatment can result in painless stable and mobile hip when the joint surfaces are not involved. A stiff joint in an Indian patient is a great disability. That may necesssitate making a diagnosis before significant symptoms appear. With the changing pattern of incidence of skeletal tuberculosis, adults may also present with hip disease. The differential diagnosis extends from transient synovitis in children to early ankylosing spondilytis in adults. Every orthopaedic surgeon is aware of these conditions but still he may find it difficult to arrive at an early diagnosis. Early diagnosis depends on being alert to the possibility of tuberculosis in a child with complaint of pain and limp. In early stages the symptoms may be intermittent, movements will be free or may be painful at extremes. The patient may still be able to squat and sit cross-legged. The X-ray and laboratory tests may be inconclusive. At this stage no active treatment need be given and the patient should be kept under observation. Analgesics may mask the symptoms and delay the diagnosis. Sometimes, inguinal lymphangitis or adenitis may cause limping. Laboratory investigation will show leukocytosis and proper antibiotics will relieve the patient. Persistent pain and limp not relieved by rest, the suspicion become stronger. The differential diagnosis at this stage is traumatic synovitis, transient synovitis, rheumatic disease, Perthes disease and slipped femoral epiphysis. If laboratory and X-ray examination is inconclusive, bed rest for 3 weeks should be 20advised. The symptoms will disappear in Transient synovitis and traumatic synovitis. At the end of six weeks, if symptoms persist investigation should be repeated. The X-ray should be carefully examined for subarticular osteoporosis. The joint space should be studied for minimal reduction. MRI and ultrasonography will show synovial effusion and edema of soft tissues. AgG and PCR may be positive. Ultrasonic guided FNAC is useful in arriving at early diagnosis. Though some surgeons advice biopsy at early stage there is a chance that the procedure may lead to morbidity.

The patient may report in any stage of the disease. Once the diagnosis is established multidrug regimen should immediately be started.21

Regarding the local treatment, depending on the stage of the disease (a) In stage-I and stage-II application of skin traction preferably bilateral to provide rest and correct the deformity. After 3-4 weeks of continuous traction, active and assisted movements in bed starts. The patient is advised to actively perform bed movements in all directions at regular intervals during the day without tiring him. After 3-4 months, partial weight bearing and after 6 months full weight bearing to be started. This regimen needs supervision and cooperation of the attendants. In case of doubt about patient's cooperation, he should be asked to come back at shorter intervals. Patients of stage III disease and patients of Stage II disease not responding to traction pose a problem regarding choice of treatment. The deformity and pain of these patients persists even after adequate period of treatment and drugs. These patients should be considered for surgery. Debridement of the joint and release of contracted structures to correct the deformity should be carried out, followed by immobilisation in plaster hip spica. Mobilisation should starts after 3 months. However, patients should be watched for recurrence of deformity. If deformity recurs 22further immobilisation should be given. These group of patients end up with ankylosis of the hip. Antitubercular drugs should be continued for 9 months.

It has been the conventional teaching that skeletal tuberculosis be it in spine or hip or any other joint ends up with fibrous ankylosis. But with advent of modern antituberculous drugs and improved methods of diagnosis, range of joint movement can be retained up to satisfactory functional level.

Selected patients as discussed in previous section will need surgical treatment to bring about healing as well as improve the ultimate function of the limb. The procedures practised are, biopsy when diagnosis is doubtful, joint clearance surgery which consists of synovectomy, debridement, and if possible relocation of articular ends. Patients reporting late with ankylosis and fixed deformities will need corrective osteotomy. Arthrodesis is not preferred by Indian patients. Excisional arthroplasty (Girdlestone) in selected patients can provide reasonable range of movement to enable the patient to squat, kneel and sit cross legged.¹⁶ In addition to movement it also corrects the deformity. The only disadvantage is shortening and unstable gait. Excisional arthroplasty can be performed both in active as well as healed stage. Post operative skeletal traction, for 8-10 weeks should be applied. In Tuli's series 90% could squat and 85%, could sit cross-legged.⁷¹ Total hip arthroplasty for ankylosed tuberculous hip has been advocated by some surgeons. Kim et al²⁷ reported Charnley type total hip arthroplasty in active disease, while Harding et al²¹ preferred to wait for 10 yrs, after healing. However, most surgeons believe that it should not be performed in active disease. It is only indicated in highly selected and carefully screened patients.^4,9

Knee joint is the largest joint of the body with the largest synovial lining. Children used to be mainly affected with tuberculosis of knee joint. In recent times the incidence in adults has increased. One has to keep tuberculosis in mind while treating monoarticular arthritis in adults and elderly. Unlike hip disease infection starts in synovium and remains predominantly synovial for considerable time. The synovium becomes hypertrophied, looks pale and riddled with tubercules. At a later stage it spreads to metaphysial area at the point of synovial attachment. Sometimes it starts from subchondral area in the form of cystic lesion. Articular cartilage is invaded from the metaphysial side. Panus formation which is common in rheumatoid arthritis is not common tuberculosis. Subchondrael erosion invades the articular cartilage from below. The articular cartilage therefore may appear normal at arthrotomy. Later on the cartilage over this area flakes off²⁰ Kerry and Martini classified tuberculosis of knee radiologically into four stages.²⁶

The patient usually presents with pain and swelling of one of the knee joints. Since there are various other conditions of the knee that presents with pain, swelling, early diagnosis is difficult. In early stages pain in a tuberculous joint can be intermittent but some swelling remains constant which should arise suspicion. In the early stage other conditions like chronic synovitis due to IDK, trauma, early monoarticular rheumatoid and nonspecific synovitis and its variants have to be considered in differential diagnosis.

The plan of treatment to some extent is similar to the treatment of hip disease. Antitubercular drug regime should be started as soon as the diagnosis is made. The local treatment of the joint depends on the stage of the disease.25

Both arthrodesis and arthroplasty are not commonly practiced procedures in Indian patients. The main disadvantage of anthrodesisis that the leg sticks out while sitting even in a chair. The advantage is that the patient can work outdoors without discomfort or pain. The absolute indication are: Patients with advanced disease resulting in painful fibrous ankylosis, painful knee following debridement procedure and sometimes while surgically correcting the fixed deformity by bony procedure, it may be necessary to fuse the joint. Charnely's compression arthrodesis is the best procedure to adopt to achieve arthrodesis. Arthroplasty in the knee joint is not to be recommended, though some surgeons have reported good result with replacement arthroplasty in old healed disease. Unlike hip disease, a tuberculous ankylosed knee joint is not suitabe site for arthroplasty. A strong, stable fixed knee is better than weak, unstable but mobile knee.

Tuberculosis ankle and foot can be discussed together because both present with pain and swelling around ankle and foot. Quite often infection from one spreads to the other. The incidence of ankle tuberculosis is about 5% of all osteoarticular tuberculosis.³⁴ The incidene of tuberculosis of foot is higher.³ Since the bones are interconnected through various small joints the disease starting in one of the bones can spread to the other. In ankle joint the infection may start in the synovium with a bony focus in subarticular region of lower tibia or talus. This type of infection is common and progressive. It spreads to extracapsular region and thereafter spreads through the synovial channels to the bones of foot. Sometimes, it starts in metaphysis of lower tibia and appears as a cystic lesion. It can remain quiescent for some time.⁵ The onset is insidious. There is swelling around the ankle joint, more prominent on the lateral side specially posterior to lateral malleous with fullness in the anterior joint line. Sometimes, it can be confused with edema of foot and neglected by general practitioner in early stage. Radiological examination reveals loss of joint space and haziness of articular marjin. As the disease spreads tendon sheaths around the joint get involved resulting in 27tuberculous tenosynovitis. Sinus formation is common in ankle and foot tuberculousis. This may lead to secondary infection. Common site of onset of focus in the foot are calcaneus, subtalar area and midtarsal joints (Fig. 1.5). Presenting symptoms are pain and swelling in the dorsum of the foot, inversion and eversion limited, and the toe movements are also restricted due to involvement of extensor tendons. Radiograph reveals marked osteoporosis of all tarsal bones and destruction of some of the bones. Mittal et al have described five type of radiological patterns.⁴²

Antituberculous drugs should be given for adequate period. If the patient has developed soft tissue involvement, below knee plaster cast and non weight bearing for 3 to 4 months, thereafter gradual weight bearing depending on improvement in healing of the disease. In ankle as well as foot tuberculosis patient may present with soft tissue swelling indicating spread of the disease to surrounding soft tissues.

Such patients may not respond to conservative treatment. If the response does not occur after 4 to 6 weeks, debridement should be carried out. Usually the joints heal with painless ankylosis. If the patient presents with sinus, immediate debridement should be done under cover of antituberculous drugs. Cystic lesion in the lower end tibia is to be curetted and if necessary packed with bone grafts. Ultimate result is good as they end up with anklysis. When extensive destruction is present or painful ankylosis of ankle joint or foot is present athrodesis may be have to done.

Tuberculous disease of the joints of upper limb lead to lesser degree of disability than the lower limb. Even if ankylosis occurs, the patient is not very much disabled except in disease of the elbow. Joints like wrist and shoulder are sorrounded by tendons and bursae which when involved give rise to additional problems. The age of incidence is comparatively later than spine and lower limb joints. The order of incidence of tuberculosis of upper limb shows elbow disease is most common while shoulder is the least. In BHU series while incidence in elbow is about 5% shoulder is about 1.5%.⁷¹ The joints being superficial, examination and diagnosis is easier.

The shoulder joint is the least common of the large joints to be affected by tuberculosis. The involvement of shoulder is more common in adults than in children. Srivastav and Singh found only one case in their series.⁶³ Tuberculosis of shoulder has rarely been reported in the past.⁴⁹ In a series reported by Martini all the patients were above 20 yrs.³⁴ The synovial type of the disease is not common in shoulder joint. The focus usually starts either in head of humerus or glenoid. It is relatively less vascular and fibrotic. The atrophic type of disease which is common to shoulder joint is known as “Carries siccca” Abcess and sinus formation is rare. Sometimes, there may be extensive desctruction and formation of pus in the joint. The deltoid bursa also gets involved presenting a cystic swelling infront of the joint.

Adequate antitubercular drug regime should be instituted. The shoulder should be immobilised in optimum functional position by means of a cast for at least 3 months. Thereafter patient should be watched for pain. If pain persists abduction frame can be given till it becomes painless. Usually painless fibrous anklylosis occurs but patient can carry out routine activities due to compensatory movement at scapulothoracic level. Sometimes, patients presenting with marked swelling and sinus, debridement of the diseased tissue should be carried out under cover of antituberculous drugs.

In the upper limb, the elbow joint has the highest incidence of tuberculous infection. The incidence is about 2-5%. The disease most commonly starts in the olecranon. It can also start in the lower end of humerus. As the infection spreads to the joint cavity, the joint gets filled up with casseous matter. Progress of the disease may lead to sinus formation.

In addition to administration of antituberculous drugs, the joint should be immobilised in an above elbow gutter cast either of plaster or plastic splint in an optimum position. Complete immobilisation should be avoided with the hope of retaining some movement at the end of the treatment. If the patient presents with complete loss of joint space and destruction of bone, plaster immobilisation can be given. In such cases ankylosis is the end result. However, care should be taken to obtain optimum position while immobilising the joint. Debridement of the joint can be performed if adequate response to antitubercular 30treatment does not occur or there are sinuses present. Some surgeons have advocated excisional arthroplasty of the ankylosed joint. However, ankylosed elbow joint in optimum position retains stability and strength in comparison to excisional arthroplasty.

Tuberculosis of wrist joint is not very frequent and its incidence is about 1-2% of skeletal tuberculosis. As in other joints of upper limb it is more common in adults than in children. The disease starts either in the lower end of radius or in one of the carpal bones. More often in the capitate. Because of the free communication between synovial spaces, the infection spreads rapidly throughout the carpus and there is wide spread involvement of bone. If the disease progresses without treatment, the process involves the capsule and progresses to infect the synovial sheath, of both flexor and extensor tendons. Abscess formation, sinuses and enlargement of regional lymph nodes are common. Sometimes, there may be only tuberculous tenosynovitis involving the tendon sheaths. Ultimately, the wrist joint gets involved. Patient presents with pain and limitation of movement of the wrist joint. In the early stage some fullness will be seen on the dorsal aspect. In later stage there will be flexion deformity, finger movement will also be limited. The wrist is held in partly flexed position with fingers extended at metacorpo-phalangeal joint. On palpation there may be a boggy swelling around the joint. X-ray shows rerifaction of bones of the wrist joint, bony erosion, and there may be an osteolytic lesion in the lower end of radius. Diagnosis may be confused with monoarticular rheumatoid arthritis. Laboratory investigations will help in the diagnosis. Synovial biopsy will confirm the diagnosis.

Anti-tubercular drugs to be started and continued for 9-12 months. The joint should be immobilised in below elbow cast for first 3-4 months. Thereafter gradual mobilisation and rest to the joint by splint is advised. Conservative treatment is successful in most of the cases. The disease heals by producing fibrous ankylosis of the joint. Surgery in the form of synovectomy is indicated if the disease does not respond to treatment, tendon sheaths are involved or multiple sinuses are present. Arthrodesis is rarely required.

Sacroiliac joint involvement occurs in about 5% of cases of skeletal tuberculosis. One interesting aspect of sacroiliac disease is, it can mimic 31the presenting symptoms of spinal disorder as well as hip disorder. Sacrailiac tuberculosis is common in adults, specially in ladies in child bearing age. The disease can start in the lateral mass of sacrum or ileum. Since the sacroiliac joint is a synovial joint the disease can also start in the synovium. Caseation, cold abcess formation and ultimately extension of cold abcess posteriorly to form sinuses. Pelvic abcess can sometimes occur.

Tuberculosis of bone without involvement of spine or joint is uncommon. Hence, the diagnosis is often missed unless the clinician is aware of the possibility. Since the symptoms are mild to begin with and slow to progress it fails to attract attention.

It is observed from the above reports that tuberculosis osteomylitis is more common in short tubular bones. Another type of tuberculosis is cystic type which may be seen in the long bones. The cystic lesions, are usually the result of the infection being contained by the tissue reaction of the patient. If it is situated at the end of a bone it may invade the joint. There may be multicystic forms also. Multicystic and multifocal, tuberculosis were common in the past. At present the incidence is not that high.⁷² However, with the rising incidence of immunocompromised patient, multiple site involvement is seen frequently (Fig. 1.7). The sequence of pathological changes depends whether it is in a small bone, short tubular bone or long bone. In the small bone it soon spreads in the body of the bone and involves small joints. In short tubular bone like metacarpal, metatarsal or phalanx, infection commences in the medullary canal and produces mass of granulation tissue. The cortex is eroded from within and there is extensive subperiosteal bone formation. The bone appears expanded. This process leads to what is known as tuberculous dactylitis (Spina ventosa). In the 33long bone the changes resemble pyogenic chronic osteomylitis. In children sequestration of diaphysis has also been reported.³⁴ The presenting symptoms depends on the bone involved. Pain and swelling are the common presenting symptoms. The pain responds temporarily to analgesics and reappears when analgesic is stopped. Mild pain and swelling of bone, with overlying boggy swelling which is slightly warm should alert the surgeon to the possibility of tubercular osteomylites. There may be sinus formation. Regional lymph glands are enlarged. X-ray picture in tuberculous osteomylites of tubular bones shows periosteal bone formation and destruction of cortex in some places. There may be small cavities in medullary canal with small flaky sequestrum seen inside the cavities. X-ray picture of dactylitis of the metatarsals will show expansion of both the cortex with loculations inside. It has to be differentiated from enchondroma. Author has recorded a case where X-ray suggestive of dactylitis but biopsy revealed nurolemoma. Histopathological study confirms the diagnosis. In early stages when X-Ray picture is doubtful. CT or MRI will be helpful.

Chemotherapy usually results in healing of the lesion. Martini reports 92% success with chemotherapy.³⁴ If the patient does not respond to chemotherapy or there is doubts in diagnosis as in dactylitis, or the presence of abcess, surgical curettage has to be undertaken. Superadded pyogenic infection may lead to persistence of sinus. Administration of proper antibiotic with or without surgery heals the lesion.