Osteoarthritis Imaging

Osteoarthritis Imaging

Osteoarthritis or degenerative joint disease (DJD) is an asymmetric, usually bilateral mechanical degenerative process that involves joints significantly involved in weight bearing, such as the hip, knee, and spine, and those involved in frequent repetitive mechanical trauma, such as the distal interphalangeal joints of the fingers, trapezium–first metacarpal joint, trapezium- scaphoid joint, and metatarsophalangeal joint of the great toe. It is the most common arthritis, and it is estimated that 80% of the population with more than 50 years will…

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Spinal Trauma

Spinal Trauma

Although much spinal trauma is well visualized on plain films, CT has a number of advantages over this modality. These include the demonstration of fractures not seen in plain films, an accurate determination of the amount of spinal canal encroachment by fracture fragments (Fig. 6-66A,B), the identification of neural foramen impingement by fractures involving its boundaries, and a more precise evaluation of facet disruption. MR can display impingement on the dural sac or the spinal cord by bone fragments, as…

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Sacroiliac Joint Injection

Sacroiliac Joint Injection

Indications Sacroiliac joint injection is used to treat inflammation of the sacroiliac joints secondary to trauma, rheumatoid arthritis, degenerative joint disease, or stress secondary to mechanical changes in posture or gait. Techniques After informed consent is obtained, the patient is placed in the prone position. The patient is prepared in a standard aseptic fashion over an area large enough to allow palpation of landmarks, and sterile technique is used throughout the procedure. A 6-in. (16-cm), 22-gauge needle is inserted. The…

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Other Ankle Abnormalities

Other Ankle Abnormalities

Technetium-99 scintigraphy has been valuable for detecting stress fractures of metatarsal and tarsal bones, and CT has high accuracy for detecting osteochondral fracture. In foot pain of undetermined etiology, however, MRI is an excellent screening modality because it permits direct evaluation of all osseous and soft-tissue structures. MRI is superior to any other modality in displaying tendon pathology (47,48). In tenosynovitis, MRI detects fluid within the tendon sheath as having moderate signal intensity on T1-weighted images and as hyperintense on…

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Complications of Brain Injury

Complications of Brain Injury

Brain injuries may be accompanied by a number of late or long-term complications. These secondary brain injuries include cerebral herniations, which may occur under the falx cerebri or through the tentorium. Herniations can cause compression of adjacent brain substance or vessels, with the production of secondary signs and symptoms (Fig. 6-93). Penetrating injuries or fractures can injure nearby large or small vessels, producing thrombosis, embolism, traumatic aneurysm formation, or internal carotid–cavernous sinus fistula. Basal skull fractures involving the dura and…

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Ankle Ligament Imaging

Ankle Ligament Imaging

Previously, arthrography and tenography were the primary means of imaging ankle ligament injuries. They had the limitations of being invasive, providing only an indirect depiction of ankle ligament disruption, and yielding potentially false- negative results. MRI provides a noninvasive means of directly imaging all the ligaments in the vicinity of the ankle as well as all the other osseous and soft tissues. Axial MR images provide good visualization of the tibiofibular ligaments of the tibiofibular mortise. All the lateral collateral…

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Diffuse Brain Injuries

Diffuse Brain Injuries

Diffuse brain injuries include diffuse axonal injury, diffuse cerebral swelling, and edema. Diffuse axonal injury is produced by high shearing stresses that occur at different parts of the brain, including at the gray matter-white matter interface. These shearing stresses cause axonal stretching commonly involving the corpus callosum, anterior commissure, and upper brain stem. Blood vessels may or may not be disrupted. When vessels are uninterrupted, the scattered small areas of edema are best demonstrated by T1-weighted MR images as slightly…

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Lumbar Zygapophyseal Joint Injection

Lumbar Zygapophyseal Joint Injection

Indications The lumbar zygapophyseal (facet) joints have been shown to be a potential source of pain involving the low back and buttocks. Facet joint injections can provide diagnostic as well as therapeutic benefits for patients with low back pain. Techniques After informed consent is obtained, the patient is placed in the prone position with a pillow under the pelvis to flatten the lumbar curve. The lumbar spine is palpated for the point of maximum tenderness. The patient is prepared in…

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Spondylolysis and Spondylolisthesis

Spondylolysis and Spondylolisthesis

Spondylolysis is a defect in the pars interarticularis, commonly involving the L5 and occasionally the L4 vertebrae. Most spondylolysis is thought to be produced by repetitive stress. The gravitational and muscular loads acting across the steep incline of the upper surface of the sacrum can be resolved into a shearing component, which tends to displace the L5 vertebral body forward on S1, and a compressive component at right angles to the superior surface of S1 (Fig. 6-63). In accordance with…

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Interphalangeal Joint Injection

Interphalangeal Joint Injection

Tiếng Việt >> Indications Interphalangeal joint injection is used as a therapeutic procedure to treat inflammation of the metacarpal phalangeal and interphalangeal joints due to rheumatoid arthritis and other inflammatory arthritides. Techniques After informed consent is obtained, the patient is placed in the sitting position with the arm resting on the examination table. The hand is placed with the joint extended for approach from the lateral or medial aspect, with slight traction applied to the finger. The patient is prepared…

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