POCUS artropathie

Elleboog protocol

A) Anterior transverse US image over the distal humeral metaphysis demonstrates the radial (1) and coronoid (2) fossa with the respective radial (3) and coronoid (4) recesses. These structures lie underneath the anterior fat pad (asterisks) and the brachialis muscle (BM). 

B) Anterior transverse US image over the distal humeral epiphysis shows a wavy osteochondral surface consisting of the convex capitellum (5) and the concave trochlea that exhibits two facets, lateral (6) and medial (7). The articular cartilage appears as a uniform hypoechoic band (arrows) overlying the subcondral bone. 

C) Anterior sagittal US image over the radio-capitellar joint reveals the radial fossa that houses the radial recess (4). The joint line (void arrow) separates the humeral capitellum (5) from the radial head (8). Distal to it, the annular recess (10) surrounds the radial neck (9). 

D) Anterior sagittal US image over the trochlea-ulna joint demonstrates the coronoid fossa and recess in a cranial position. The joint line (open arrow) separates the trochlea from the coronoid process (9). E) Posterior sagittal US image over the olecranon fossa demonstrates the posterior fat pad (asterisk) and the olecranon recess (11) deep to the triceps muscle (TRI). The joint line (void arrow) lies between the posterior aspect of the trochlea and the olecranon process (12).

Knie protocol

A) Anterior mid-sagittal US image demonstrates the patella (1) and the distal femur (2). The suprapatellar recess (arrows) appears as a hypoechoic linear band located below the quadriceps tendon (Qt), between the suprapatellar (3) and the prefemoral (4) fat pads. 

B) Anterolateral transverse US image shows the patellofemoral joint and the lateral parapatellar recess (void arrow) located between the lateral patellar retinaculum (arrowheads) and the lateral femoral condyle. 

C) Transverse US image of the femoral trochlea at maximum degree of knee flexion. The medial (5) and lateral (6) facets of the trochlea are invested by a thick band of cartilage (arrows). 

D) Coronal US image over the medial femorotibial space shows the medial meniscus (asterisk). The boundaries (open arrowheads) of the femur (2) and tibia (7) are regular and flat up to the joint space.

Ankle protocol

A) Anterior mid-sagittal US image over the tibiotalar joint (void arrow) demonstrates the distal tibial epiphysis and the talus, the latter consisting of three parts: the convex dome (2) covered with cartilage (narrow arrow), the concave neck (3) and the prominent head (4). More distally, the dorsal aspect of the talonavicular joint is seen (arrowheads). The anterior fat pad (asterisks) extends over the talar dome and neck. 

B) Anterior transverse US image over the talar dome reveals a flat bony surface (arrows) covered with a thin layer of cartilage. 

C) Lateral transverse US image over the sinus tarsi. The lateral malleolus (5), the talar neck posteriorly and the calcaneus (6) anteriorly are the main landmarks to identify the anterior recess of the subtalar joints. The sinus tarsi is a fat-filled space and looks hyperechoic normally. 

D) Posterior mid-sagittal US image over the Achilles tendon (AT). Below this tendon, the preachilles (Kager) fat pad (KFP) and the flexor hallucis longus muscle (FHL) are found. The posterior recess of the tibiotalar joint (void arrow) lies between the posterior malleolus (1) and the posterior aspect of the talar dome (2), underneath the posterior fat pad (asterisk). The posterior recess of the subtalar joint lies between the talus and calcaneus (8). A prominent posterior process of the talus (white arrowhead) may mimic an osteophyte.