Reason: left MCP laxity - r/o RCL tear History: left MCP laxity - r/o RCL tear LIGAMENTS: There is disruption of the proximal fibers of the radial collateral ligament of the interphalangeal joint of the thumb (image 6; series 1101). There is disruption of the distal fibers of the ulnar collateral ligament of the IP joint of the thumb (image 5; series 1101).There is disruption of the distal fibers of the ulnar collateral ligament of the MCP joint of the thumb (image 6; series 1101 and image 11 of series 701). The radial collateral ligament of the MCP joint of the thumb appears intact.TENDONS: The flexor and extensor tendons of the thumb appear intact. The A1 pulley appears intact. The oblique pulley appears intact. There is "bowstringing" of the flexor pollicis longus tendon at the level of the midportion and head of the proximal phalanx of the thumb likely representing disruption of the A2 pulley of the thumb. There is globular decreased signal abnormality along the volar aspect of the head of the proximal phalanx of the thumb which is nonspecific and may represent a combination of scarring, old blood products, and perhaps remnants of the aforementioned A2 pulley of the thumb (image 8; series 1601).BONES: There is a minimally displaced volar plate fracture of the base of the distal phalanx of the thumb. There is bone marrow signal abnormality within the head of the proximal phalanx of the thumb which may reflect a contusion.ADDITIONAL
1. Findings consistent with the patient's known history of prior interphalangeal joint of the thumb dislocation including disruption of the radial and ulnar collateral ligaments of the interphalangeal joint of the thumb. There is a minimally displace the volar plate fracture of the base of the distal phalanx of the thumb.2. Disruption of the A2 pulley of the thumb. Globular signal abnormality along the volar aspect of the head of the proximal phalanx of the thumb may reflect a combination of scarring, old blood products and perhaps fragments of the aforementioned disrupted A2 pulley.3. Tearing of the ulnar collateral ligament of the MCP joint without convincing evidence of a Stener lesion. The radial collateral ligament of the MCP joint appears intact.4. Bone contusion of the proximal phalanx of the thumb and other findings as described above.