Ultrasound signs of ankle joint injuries

Ankle ligament ruptures.

Injuries to the ankle ligaments are mostly found in athletes. A typical mechanism of injury is the inversion of the foot inwards or outwards when the limb is loaded (running, jumping off the equipment, jumping). Another mechanism of injury is also possible, the cause of which is the rotation of the foot relative to the longitudinal axis of the shin. Such injuries are most often found in skiers, when, while descending the mountains, the tip of the ski touches some obstacle, and the skier continues to move forward by inertia. At this point, the foot, fixed by the boot, remains in place, and the shin continues to move forward, resulting in forced eversion of the foot (rotation of the foot in the ankle joint around the longitudinal axis of the shin outwards). Based on the above-described mechanisms of injury development, various ligamentous components of the ankle joint are damaged. For example, the lateral collateral ligaments are damaged during supination and inversion of the foot, and the deltoid and tibiofibular ligaments can be damaged during pronation and eversion.

Depending on the severity of the injury, a distinction should be made between ruptures (ligament sprains) and ligament ruptures. In the case of a partial rupture, patients complain of local pain at the sites of attachment of the damaged ligaments to the bone, which intensifies upon palpation. Swelling and bruising caused by hemarthrosis are visualized in the area of injury. A characteristic clinical sign of injury to the anterior portions of the lateral ligaments is increased pain when checking the "drawer" symptom. In the case of injury to the tibiofibular ligaments, most patients experience increased local pain when extending the foot at the ankle joint. In the case of ruptures and tears of the lateral lateral ligaments, the pain intensifies when bringing the foot into a supination and inversion position, and in the case of injuries to the deltoid and tibiofibular ligaments - pronation and eversion.

In case of deltoid ligament rupture, a characteristic sign is diastasis between the medial malleolus and the medial lateral surface of the talus. The talus is displaced inwards. Ultrasound examination reveals fraying and disruption of the typical course of the ligament fibers. At the same time, the ligament thickens, its echogenicity decreases. Hypoechoic fibers of the torn ligament are clearly visible against the background of echogenic fatty tissue.

In case of a partial rupture of the anterior talofibular ligament, an area of reduced echogenicity is determined in the rupture zone - a hematoma and edema of the surrounding soft tissues.

Rupture of the ankle tendons.

A common problem for the group of lateral or peroneal tendons (tendon of the peroneus longus and tendon of the peroneus brevis) is subluxation and dislocation. Ruptures of these tendons are extremely rare. They are usually observed in injuries to the calcaneus and lateral malleolus, which are accompanied by dislocation of the peroneal tendons. Sometimes there are signs of tendinitis and tenosynovitis. The clinical picture is characterized by a recurrent course, pain along the tendon, increasing with palpation. The tendon is thickened in volume, its structure is heterogeneous due to edema.

As for the group of medial tendons (tendon of the posterior tibialis muscle, tendon of the long flexor of the fingers and tendon of the long flexor of the hallucis), they are more characterized by the presence of inflammatory changes and tendinitis, tendinosis and tenosynovitis. Ruptures of the tendon of the posterior tibialis muscle can be observed in the projection of the medial malleolus, and the presence of a chronic rupture is most typical.

Ultrasound examination (US) of a rupture shows a hypoechoic area in the tendon and fluid in its sheath. Ruptures of the tendons of the anterior group are very rare. They occur in ballet injuries, in football players. Ultrasound manifestations are the same as in ruptures of the tendons of the medial and lateral groups. Also observed is discontinuity of the course of the fibers, effusion in the synovial sheath of the tendon.

Tendinitis of the ankle tendons.

In the presence of tendonitis, there will also be fluid in the sheath surrounding the tendon, but the tendon itself will look normal. The diagnosis in this case will already be formulated as tenosynovitis. Tenosynovitis is usually a consequence of mechanical action on the tendon or as a result of a disease - rheumatoid arthritis. Rheumatoid damage is characterized by a decrease in the diameter of the tendon, while normal inflammation is characterized by a thickening of the tendon. It is necessary to differentiate effusion in the synovial sheath of the tendon and hygromas. Hygromas have a limited extent and rounded edges.

Achilles tendon rupture.

Achilles tendon ruptures occur solely as a result of trauma. They can occur not only in athletes exposed to excessive stress loads, but also in ordinary people after an awkward movement and inadequate load on the tendon. Sometimes, in cases of incomplete rupture, the diagnosis may be overlooked by a clinician.

Ultrasound data play an important role in making a diagnosis. In case of complete ruptures of the Achilles tendon, a violation of the integrity of the fibers, the appearance of a hypoechoic zone of varying length at the rupture site, and fiber diastasis are determined. The rupture zone is usually located 2-6 cm above the tendon attachment site. Sometimes, with a complete rupture, the tendon is not detected in a typical place. The hematoma around the rupture is usually small due to weak vascularization of the tendon.

Using ultrasound, it is possible to fairly reliably establish the level and size of the rupture, as well as to distinguish a partial rupture from a complete one. Thus, with a partial rupture of the tendon, the tissue defect is localized in the thickness of the tendon and only one contour is interrupted.

It should be remembered that when a Baker's cyst ruptures, fluid can descend to the level of the Achilles tendon and simulate its damage. Ruptures of the medial head of the gastrocnemius muscle can also cause pain in the projection of the muscular-tendon junction.

Using ultrasound, it is quite easy to exclude pathological changes in the Achilles tendon. In old Achilles tendon ruptures, up to 6 weeks old, a persistent tissue defect is usually visible at the rupture site, combined with areas of fibrosis and small calcifications. The tendon is usually thickened, and its echogenicity is reduced. Ultrasound allows monitoring of treatment for Achilles tendon injuries.

During surgical restoration of torn tendon ends, hyperechoic ligatures are visualized in the tendon structure. Using ultrasound angiography techniques, it is possible to accurately assess the vascular reaction in the surgical area and in the surrounding tissues, and, therefore, to promptly detect possible inflammation.

Functional tests performed under ultrasound control help to identify diastasis and assess the nature of the restoration of tendon activity.

Achilles tendonitis.

In acute inflammatory process in the Achilles tendon, the tendon is sharply thickened on echograms, its echogenicity is reduced. The retrocalcaneal bursa may be involved in the inflammatory process. With the development of inflammatory changes, its size increases by more than 3 mm. In this case, a hypoechoic stretched bursa is visualized behind the Achilles tendon. Inflammatory blood flow may be recorded in the walls of the bursa.

The transition of inflammation into a chronic process is accompanied by the appearance of heterogeneity in the structure and the presence of calcifications in the Achilles tendon. Calcifications also form at the site of the former tendon rupture and are most often localized at the site of attachment of the tendon to the calcaneus. Repeated ruptures often occur in this area.

Achilles tendinosis.

With age, due to the development of degenerative changes in the Achilles tendon, its structure changes. The tendon becomes heterogeneous, thickened, and calcifications appear. With inadequate load on the tendon, its partial or complete rupture is possible.

Heel spur.

Bone growths in the form of a thorn or wedge in the area of the plantar surface of the calcaneal tubercle or at the attachment site of the Achilles tendon are called heel spurs.

Most often, heel spurs are a consequence of involutional changes in the human body. The clinical picture is characterized by burning pain when putting weight on the heel, which patients define as a feeling of a "nail in the heel."

Clinical symptoms are caused primarily by changes in soft tissues: inflammation of the deep mucous bags (calcaneal bursitis, Achilles bursitis) and periostitis. Echographically, hyperechoic inclusions are determined in the area of the calcaneal tubercle, around which inflammatory infiltration occurs due to constant trauma.

Morton's neuroma.

This relatively rare condition is one of the causes of metatarsalgia. One of the causes of Morton's neuroma is considered to be compression of the branches of the common plantar digital nerves by the heads of the metatarsal bones.

Trauma, pressure from tight shoes, and overload also influence the development of the disease.

The clinical picture is characterized by severe burning pain in the area of the third interdigital space on the foot, which occurs when standing and walking in tight shoes and weakens after unloading the foot or removing tight shoes. Echographically, it is characterized by the occurrence of thickening between the 3rd and 4th interdigital spaces.

Arthrosis.

In osteoarthrosis, the articular cartilage is primarily affected. As is known, during various movements, cartilage acts as a shock absorber, reducing the pressure on the articulating surfaces of the bones and ensuring their smooth sliding relative to each other. The main causes of dystrophic changes in the articular cartilage of the lower leg are overload, healthy articular cartilage or its damage. Due to constant load, aging and destruction of some fibers occurs.

Chronic inflammatory processes in the joint, systemic metabolic changes, such as gout, endocrine disorders (hypothyroidism) lead to changes in the structure of the articular cartilage. The cartilage layer becomes thinner and thinner, until it is completely destroyed. Along with the cartilage, the bone tissue underneath it changes. Bone growths - osteophytes - are formed along the edges of the joint.

Most often, arthrosis of the metatarsophalangeal joint of the first toe is encountered, which is characterized by pain that occurs during physical activity. Constant pain and its connection with physical activity distinguish this disease from gout. Gradually, limitations in flexion of the big toe in the joint develop, and its deformation occurs.

Rheumatoid arthritis.

The chronic stage of the disease is characterized by perivascular infiltration of the synovial membrane. Proliferation of the synovial membrane leads to the formation of nodules, joint deformation and ankylosis, since over time these nodules undergo fibrosis and calcification. Inflammation of the periarticular soft tissues, developing in parallel with changes in the joint, leads to the development of edema and is accompanied by pain during movement.

Limiting the mobility of the joint and fixing it in a flexed position leads to the gradual development of deformation of the joint itself, contractures of muscles and tendons, and the development of joint instability.