الفهرس 
Introduction &Aim Of The WorkOnly 14 pages are availabe for public view
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Abstract
The human wrist joint is a complex arrangement of small bones and ligaments that form a link from the powerful forearm to the hand. These ligaments has the ability to place the hand in three dimensional space that is essential for normal daily function of the upper extremity.
Wrist instabilities are caused by ligament and bone abnormalities that result in modification of the normal relationship between carpal bones.
Fractures and dislocations of carpal bones are more common in young active patients .These injuries can lead to pain, disfunction, and loss of productivity.
The most common carpal dislocations are perilunate dislocations. These injuries are charatarized by severe disruption of the soft tissues and sometimes bones of the wrist with dislocation of the capitate head from the concavity of the distal lunate.
Unstable scaphoid fractures, scapholunate dissociation, and lunotriquatral dissociation are considered the most common causes of carpal instability The first two result in DISI and the third may result in VISI.
Conventional radiography remains the primary imaging modality it has a fundamental role in the evaluation of the hand and wrist following trauma however in ligamentus injury the conventional radiographic signs only develop later after injury and direct visualization of the ligaments is required to diagnose their disruption. If primary ligament repair is planned this has to be undertaken early or there is a high risk of none healing
Also Carpal Fractures may not be recognized on standard radiographs because of superimposition of adjacent bones and diagnosis may require special radiographic views or other imaging techniques such as CT or scintigraphy .
The aim with cross-sectional imaging modalities is to identify the nature and extent of ligamentous disruption and to identify any associated abnormality
CT on its own is of less value in the diagnosis of carpal instability. However, combined with an arthrographic injection demonstration of the intrinsic ligaments can be achieved. CT arthrography is more sensitive especially for partial injuries to the intrinsic ligaments.
MRI has a high clinical impact in the early diagnosis of acute wrist trauma. MRI allows not only better evaluation of osseous injury and soft tissue to detect occult carpal fractures but also the avoidance of false-positive diagnoses and inadequate therapy.
The use of MRI for detection of defects in the SLIL and LTIL has been repeatedly demonstrated while direct MRI evidence for LTIL tear is notably more difficult to identify than for the SLIL
MR arthrography is superior to conventional MR imaging, in that it allows for identification of the size, morphology, and location of an LT& SL ligament tear. This includes both partial and complete tears.
The diagnostic accuracy of MR arthrography in the SLIL and LTIL tears was intermediate between that of MRI and that of MDCT arthrography.