Lunotriquetral Ballottement Test also called Reagan Test, it is used to evaluate the integrity of the lunotriquetral ligament of the wrist joint.
The goal of the test is to control the lunate and triquetrum separately so that they can be moved in relation to each other.
Lunotriquetral Ballottement Test is positive when there is an increased laxity and accompanying pain at the Lunotriquetral joint region.
A comparative study by P LaStayo 1 of the scaphoid shift test (SST), the ballottement test (BALLOT), and the ulnomeniscotriquetral dorsal glide test (UMTDG), and describes the clinical and arthroscopic examination method; and analyzes the sensitivities, specificities, and predictive values of these provocative tests relative to the arthroscopic findings in 50 painful wrists. Of those patients who needed arthroscopic inspection, the provocative tests proved to be more efficient at predicting the absence of injury than at predicting its presence.
He defines the Sensitivity & Specificity of the Lunotriquetral Ballottement Test as following:
Lunotriquetral instability can result from trauma involving hyper pronation or hyperextension.
Patients report pain in the wrist. Tenderness to palpation over the triquetrolunate joint and pain with motion can be provoked, but pronation and supination do not cause any pain.
The injury does not necessarily involve loss of strength. Patients occasionally describe the instability as a clicking that occurs during wrist motion.
The landmark for the triquetrum is the pisiform bone, which is the most prominent bony landmark on volar and ulnar aspect of the wrist.
The Lunotriquetral joint has two transverse intercarpal ligaments (palmar and dorsal) connecting the palmar and dorsal aspects of the two bones, and a fibrocartilaginous membrane closing the joint proximally. The palmar Lunotriquetral ligament is thicker and stronger than its dorsal counterpart (average yield strengths: 301 N and 121 N) with the proximal portion being the weakest (64 N).
The fibers of the two Lunotriquetral ligaments are under greater tension through all ranges of motion than the fibers of the Scapholunate ligaments. The most distal fibers of palmar and dorsal Lunotriquetral ligaments are often connected to the distal fibers of the Scapholunate ligaments, forming the palmar and dorsal scaphotriquetral ligaments.