Enthesopathy are a group of pathological processes with an inflammatory and degenerative–dystrophic component that occur in the area of attachment of tendons, less often aponeuroses, ligaments and joint capsules to bones. They are manifested by pain at rest and during physical exertion with the participation of the affected anatomical structure, restriction of movements, local swelling, hyperemia and soreness during palpation. They are diagnosed on the basis of complaints, anamnesis, radiography, MRI and ultrasound of the joints. Treatment of enthesopathy is complex, includes physiotherapy, drug therapy, massage, physical therapy. If conservative methods are ineffective, surgical interventions are performed.
Enthesopathy is a common group of diseases of the musculoskeletal system. The name comes from the word “enthesis” or “enthesis”, meaning the place of attachment of connective tissue formations to bone structures, has been used in medical literature since the 60s of the last century.
Some experts adhere to a broader interpretation of this term and include in the group of enthesopathies not only the lesions of the entheses themselves, but also tendinitis of adjacent tendon areas, as well as inflammatory processes in the area of tendon bags. According to statistics, enthesopathy are diagnosed in 35-85% of patients suffering from joint diseases. They are often detected in autoimmune pathologies, they occur in athletes and people of some professions. They tend to have a long course with gradual progression, degenerative-dystrophic degeneration of tissues, deterioration of function and an increase in the likelihood of traumatization of the altered anatomical structure.
Taking into account the etiological factor, two types of enthesopathies are distinguished in traumatology and orthopedics: primary inflammatory and primary degenerative. Primary inflammatory pathology develops with the spread of inflammation from adjacent joints in arthritis. The primary degenerative process occurs as a result of repeated minor injuries with constant overloads or is the outcome of a single major injury (tear, rupture in the area of entesis). The cause of overload can be both high physical activity and a violation of the biomechanics of movements in diseases of the musculoskeletal system. Factors that increase the likelihood of the formation of enesopathies are considered:
- Monotonous physical activity. Pathology is often detected in athletes (tennis players, runners, football players, weightlifters, etc.) and persons of some professions (builders, movers, painters, circus and ballet artists), which is due to repetitive movements that cause excessive load and repeated microtraumas of entheses. Permanent microtraumatization is often aggravated by more severe injuries with the formation of areas of scar tissue.
- Diseases of the joints. Experts consider enthesopathies as a rather specific sign of seronegative spondyloarthropathies, including ankylosing spondylitis, psoriatic arthritis, Reiter’s disease and other reactive joint lesions of urogenic origin, as well as reactive arthritis that occurs against the background of infectious enterocolitis, ulcerative colitis and Crohn’s disease. Pathology can be detected with arthrosis, especially often occurs with degenerative-dystrophic lesions of the knee and hip joints.
- Trophic disorders. Deterioration of tissue metabolism in the area of entheses can be provoked by disorders of nervous regulation in root syndromes, insufficiency of local blood supply in cardiovascular diseases, changes in the hormonal background during menopause in women.
- Connective tissue dysplasia. Congenital inferiority of connective tissue structures is associated with a high probability of microtraumatization of the tendon-ligamentous apparatus and the subsequent development of inflammation even with minor physical exertion. Hereditary collagenopathies are one of the main causes of enthesis damage in young people.
Enthesopathy is based on inflammatory and degenerative processes in the enthesis zone. The peculiarity of this anatomical structure is inelasticity and high mechanical strength under relatively unfavorable conditions of local circulation. The entheses are deprived of their own vessels, the tissues are nourished by the arteries that provide blood supply to the adjacent bones and tendons. Under load, a zone of the most intense tension is formed in the enthesis region. Due to the high mechanical strength, most fibers remain intact, so a single micro-injury is asymptomatic and remains unnoticed.
At the same time, single microfractures are formed in the areas of connection of collagen bundles with bone tissue (with fibrous entesis) or transformation of collagen fibers into fibrous cartilage (with fibrous-cartilaginous junction). With repeated microtraumatization, the number of ruptures gradually increases. Zones of fatty degeneration appear in the tendon tissue. All of the above negatively affects the strength of the enthesis, increases the likelihood of its subsequent damage and contributes to the development of inflammation. With a primary inflammatory lesion, the reverse mechanism is observed. Inflammatory phenomena create favorable conditions for the appearance of micro-fractures, tendon tissue is scarred and undergoes fatty degeneration, areas of degeneration of enthesis are formed.
The most common lesions of enthesis are epicondylitis, trochanteritis, enthesopathy of the sciatic tubercle, “crow’s foot” and the lateral surface of the patella, achillodenia and subcutaneous bursitis. Common symptoms of pathologies of this group are local pains at the place of attachment of the tendon with the tension of the corresponding muscles or being in a certain position. The pain syndrome increases with resistance to movement. Palpation determines soreness, sometimes bone outgrowths and limited swelling of soft tissues are detected.
Epicondylitis of the elbow joint can be external (“tennis player’s elbow”) and internal (“golfer’s elbow”), affects, respectively, the places of attachment of tendons to the outer and inner condyles of the humerus. Lateral epicondylitis is characterized by clearly localized pain that occurs after an unusual load and increases with resistance to an attempt to extend the wrist joint. Medial epicondylitis is manifested by local soreness, which increases with resistance to wrist flexion. The function of the elbow joint is usually preserved.
Trochanteritis, as a rule, develops against the background of hip arthrosis, is more often diagnosed in female patients over the age of 40. There is soreness in the area of the large spit when trying to lie on the sore side. Enthesopathy usually has no effect on the volume of movements, there may be some limitations due to concomitant arthrosis. Palpation of the trochanter is painful. There is an increase in pain syndrome with resistance to hip abduction. Patients with sciatic tubercle enthesopathy complain of pain that occurs in a sitting position (with body pressure on the affected area).
Anzerin bursitis or entesis lesion in the “crow’s foot” zone is inflammation at the site of attachment of the tendons of three muscles: semi–tendon, elegant and tailor-made on the inner surface of the lower leg below the knee joint. It is usually diagnosed in middle-aged and elderly women who are overweight and suffering from gonarthrosis. It is manifested by pain at the beginning of the movement and when climbing the steps, local soreness in the projection of enthesis. Another enthesopathy of the knee joint area is the process in the zone of attachment of the patella’s own ligament along its outer or inner edge. Like the previous pathology, it is more often detected with arthrosis, accompanied by pain during palpation and movements.
Achillodynia is often diagnosed in athletes, people with hereditary collagenopathies. It is characterized by intense pain during movements and prolonged stay in a standing position. Subcutaneous bursitis can be primarily inflammatory or primarily degenerative. In the first case, it is found in patients with spondyloarthropathies, in the second (heel spur) – it is observed in people aged 40 years and older. Typical pain when resting on the foot, more pronounced at the time of the start of walking.
Depending on the etiology of the disease, diagnostic measures are carried out by orthopedic traumatologists or rheumatologists. If enthesopathies occur against the background of urogenic and enterogenic spondyloarthropathies, a referral to the listed specialists can be issued by a urologist, proctologist or an infectious disease specialist. Until recently, the diagnosis was based on clinical data and the results of X-ray examination. Currently, the list of surveys includes the following procedures:
- Survey, inspection. Predisposing factors are often noted in the anamnesis. If spondyloarthropathy is suspected, a family history is studied, characteristic signs from other organs are revealed. During an objective examination, local soreness is detected, sometimes – limited swelling and bone growths, increased pain when the corresponding muscle is strained, especially against the background of resistance to movement.
- Joint x-ray. In the early stages, changes in arthrograms are absent or poorly expressed. With the progression of the process, local osteopenia, discontinuity of the cortical layer, ossifications of the fibrous part of the enthesis, bone outgrowths are visualized.
- Echography. At an early stage, ultrasound of the joints confirms violations of the structure of fibrous enthesis. Subsequently, the picture is supplemented by areas of ossification of the tendon part of the joint and bone erosions.
- MRI. The entesis itself is poorly visible during scanning, but the method provides high accuracy in detecting specific changes in nearby anatomical formations. MRI of the bone confirms the presence of bone edema even before the appearance of radiological signs of enthesopathy.
Taking into account the localization and clinical manifestations of the disease, differential diagnosis is carried out with arthritis, arthrosis, bursitis, tendinitis, tendovaginitis, fibrositis, other inflammatory and degenerative-dystrophic processes in the articular region and periarticular zone. When carrying out differentiation, it is taken into account that enthesopathies can be combined with the listed pathologies.
Treatment of entesis lesions is performed on an outpatient basis, includes drug therapy and non-drug methods of exposure. Patients are recommended to change motor stereotypes to reduce the load on the affected entheses. Operations are required relatively rarely, they are indicated for severe pain syndrome and ineffectiveness of conservative therapy. The list of possible therapeutic measures includes:
- Drug blockades. Local administration of glucocorticosteroid drugs (periarticular blockades) is the most effective way to quickly eliminate severe pain syndrome. Frequent injections of medications can provoke degenerative-dystrophic changes in bone and soft tissues, so medications are prescribed with caution no more than 1-2 times a year with a course of no more than 3 injections.
- Physical therapy. The most important role in eliminating or reducing the manifestations of pathology is played by physical therapy. During the period of exacerbation, passive movements, stretching exercises are used, in the remission phase, a program is made to strengthen the muscles of the affected segment. In addition, laser therapy, ultrasound, cryotherapy, reflexology are used. Manual techniques (massage, manual therapy) are widely used. Many experts note the effectiveness of shock wave therapy.
- Surgical interventions. According to the indications, tenotomy or tendoperiosteotomy is performed, sometimes in combination with other surgical techniques (for example, fasciotomy). In recent years, endoscopic operations have been successfully used for enthesopathies of some localizations.
Taking NSAIDs in therapeutic dosages in most cases does not provide the desired effect, there is only a slight decrease in soreness while limiting the load on the affected segment to the maximum. Pain and inflammation in some enthesopathies of superficial localizations temporarily decrease after applying local remedies containing NSAIDs and warming ointments. With a deep location of the entheses, local drugs are ineffective.
Prognosis and prevention
The prognosis for enthesopathies is relatively favorable. With a properly selected treatment regimen, compliance with the doctor’s recommendations, the clinical manifestations of the disease decrease or disappear. At the same time, the disease is prone to a chronic course, complete recovery is rarely observed, with an increase in the load on the segment or exacerbation of pathologies of nearby joints, there is a high probability of relapses. Over time, the pathology progresses, which leads to a deterioration in the function of the limb. Preventive measures involve the rejection of excessive monotonous physical exertion, compliance with the technique of performing movements during sports and professional activities, timely treatment of vascular pathology, joint and nervous system lesions.
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