Chapter 14 Ankle and Foot AXIAL (LONG AXIS) 530 CORONAL (SHORT AXIS) 554 SAGITTAL 582 Ankle and Foot Axial 1 Diagnostic Consideration The terms “axial” and “coronal” can be confusing when describing planes of imaging in the foot. Although the ankle has coronal and axial planes, sections through the foot are more easily described as long axis (parallel to long axis of the metatarsals) and short axis (perpendicular to long axis of the metatarsals). Ankle and Foot Axial 1 Ankle and Foot Axial 2 Ankle and Foot Axial 2 Ankle and Foot Axial 3 Pathologic Process Posterior tibial tendon tears usually occur at the level of the medial malleolus. Tears of the posterior tibial tendon can lead to a flatfoot deformity because this tendon provides a significant contribution to the longitudinal arch of the foot. Ankle and Foot Axial 3 Ankle and Foot Axial 4 Pathologic Process “High ankle sprains” involve disruption of the anterior tibiofibular ligament. Ankle and Foot Axial 4 Ankle and Foot Axial 5 Normal Anatomy The Achilles (calcaneal) tendon is normally shaped like a kidney bean on axial images. Below the tibiofibular joint space, the fibula is shaped like a comma on axial images. Above the joint, the fibula’s medial side appears flat. Pathologic Process Peroneal tendons can dislocate if the superior retinaculum is torn or lax. The tendons will be identified lateral to the fibula. Ankle and Foot Axial 5 Ankle and Foot Axial 6 Normal Variant The plantaris tendon is present in 90% of individuals. Pathologic Process The anterior talofibular ligament is the most frequently torn ankle ligament. Diagnostic Consideration The vertical portion of the spring ligament and the posterior tibial tendon should appear similar in size. A spring ligament tear will make the ligament appear attenuated; a posterior tibial tendinopathy can increase or decrease the size of the tendon. Ankle and Foot Axial 6 Ankle and Foot Axial 7 Normal Anatomy The Achilles (calcaneal) tendon may have intermediate signal between the gastrocnemius and soleus components. Diagnostic Consideration High signal can be seen normally between the plantaris tendon and the Achilles tendon and should not be mistaken for an abnormality of the Achilles tendon. Similarly, if the Achilles tendon is completely torn, the intact plantaris should not be mistaken for intact fibers of the Achilles tendon. It is normal to see intermediate signal and an increase in size of the posterior tibial tendon just proximal to its insertion on the navicular bone. Ankle and Foot Axial 7 Ankle and Foot Axial 8 Normal Variant The plantaris tendon may insert onto the Achilles (calcaneal) tendon, the posterior calcaneus, or the flexor retinaculum. Two frequently recognized types of accessory navicular bones exist. Type 1 is a small, sesamoid bone within the posterior tibial tendon near its insertion onto the navicular. Type 2 is a large, secondary ossification center that is present in about 10% of the population and has a fibrous attachment to the navicular. This can separate and become painful with repetitive trauma or overt trauma. Pathologic Process Longitudinal split tears of the peroneus brevis can be distinguished from two muscle variants, which are termed the accessory peroneus quartus and the low-lying peroneus brevis. A split tear will have one muscle belly and two tendons arising from it, whereas the low-lying peroneus brevis and the peroneus quartus will each have one tendon and one muscle belly. Ankle and Foot Axial 8 Ankle and Foot Axial 9 Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related posts: Forearm Upper Arm Plantar Plate Elbow Shoulder Knee Stay updated, free articles. Join our Telegram channel Join Tags: Netter Correlative Imaging Musculoskeletal Anatomy Jan 17, 2016 | Posted by admin in MUSCULOSKELETAL IMAGING | Comments Off on Ankle and Foot Full access? Get Clinical Tree
Chapter 14 Ankle and Foot AXIAL (LONG AXIS) 530 CORONAL (SHORT AXIS) 554 SAGITTAL 582 Ankle and Foot Axial 1 Diagnostic Consideration The terms “axial” and “coronal” can be confusing when describing planes of imaging in the foot. Although the ankle has coronal and axial planes, sections through the foot are more easily described as long axis (parallel to long axis of the metatarsals) and short axis (perpendicular to long axis of the metatarsals). Ankle and Foot Axial 1 Ankle and Foot Axial 2 Ankle and Foot Axial 2 Ankle and Foot Axial 3 Pathologic Process Posterior tibial tendon tears usually occur at the level of the medial malleolus. Tears of the posterior tibial tendon can lead to a flatfoot deformity because this tendon provides a significant contribution to the longitudinal arch of the foot. Ankle and Foot Axial 3 Ankle and Foot Axial 4 Pathologic Process “High ankle sprains” involve disruption of the anterior tibiofibular ligament. Ankle and Foot Axial 4 Ankle and Foot Axial 5 Normal Anatomy The Achilles (calcaneal) tendon is normally shaped like a kidney bean on axial images. Below the tibiofibular joint space, the fibula is shaped like a comma on axial images. Above the joint, the fibula’s medial side appears flat. Pathologic Process Peroneal tendons can dislocate if the superior retinaculum is torn or lax. The tendons will be identified lateral to the fibula. Ankle and Foot Axial 5 Ankle and Foot Axial 6 Normal Variant The plantaris tendon is present in 90% of individuals. Pathologic Process The anterior talofibular ligament is the most frequently torn ankle ligament. Diagnostic Consideration The vertical portion of the spring ligament and the posterior tibial tendon should appear similar in size. A spring ligament tear will make the ligament appear attenuated; a posterior tibial tendinopathy can increase or decrease the size of the tendon. Ankle and Foot Axial 6 Ankle and Foot Axial 7 Normal Anatomy The Achilles (calcaneal) tendon may have intermediate signal between the gastrocnemius and soleus components. Diagnostic Consideration High signal can be seen normally between the plantaris tendon and the Achilles tendon and should not be mistaken for an abnormality of the Achilles tendon. Similarly, if the Achilles tendon is completely torn, the intact plantaris should not be mistaken for intact fibers of the Achilles tendon. It is normal to see intermediate signal and an increase in size of the posterior tibial tendon just proximal to its insertion on the navicular bone. Ankle and Foot Axial 7 Ankle and Foot Axial 8 Normal Variant The plantaris tendon may insert onto the Achilles (calcaneal) tendon, the posterior calcaneus, or the flexor retinaculum. Two frequently recognized types of accessory navicular bones exist. Type 1 is a small, sesamoid bone within the posterior tibial tendon near its insertion onto the navicular. Type 2 is a large, secondary ossification center that is present in about 10% of the population and has a fibrous attachment to the navicular. This can separate and become painful with repetitive trauma or overt trauma. Pathologic Process Longitudinal split tears of the peroneus brevis can be distinguished from two muscle variants, which are termed the accessory peroneus quartus and the low-lying peroneus brevis. A split tear will have one muscle belly and two tendons arising from it, whereas the low-lying peroneus brevis and the peroneus quartus will each have one tendon and one muscle belly. Ankle and Foot Axial 8 Ankle and Foot Axial 9 Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related posts: Forearm Upper Arm Plantar Plate Elbow Shoulder Knee Stay updated, free articles. Join our Telegram channel Join
