Ultrasound Evaluation of Gamekeeper's Thumb or Skier's Thumb
Gamekeeper's thumb, also known as skier's thumb, involves an injury to the ulnar collateral ligament of the thumb. Today's tip from the Gulfcoast Ultrasound Institute sheds light on key points in assessing this condition.
Placing the Ultrasound Probe
Positioning is fundamental when evaluating the ulnar collateral ligament. Placing the ultrasound probe in the coronal plane relative to the thumb is essential. To achieve this, a simple yet effective technique involves positioning the thumb overhanging the edge of a rolled-up towel. This positioning facilitates the direct placement of the transducer in the coronal plane, optimizing imaging quality.
Identifying Bone Landmarks
Recognition of characteristic bone contours is pivotal for proper imaging orientation. Observing a concavity at the first metacarpal and a smaller concavity at the proximal phalanx ensures correct alignment within the imaging plane. These landmarks serve as anchors for assessing the ulnar collateral ligament.
Visualizing the Ulnar Collateral Ligament
The normal appearance of the ulnar collateral ligament presents as a hyperechoic and fibular structure, connecting the previously mentioned bone landmarks. However, it's important to note that the ligament might appear slightly hypoechoic due to surrounding structures.
Assessing the Adductor Aponeurosis
Another significant structure to visualize is the overlying adductor aponeurosis, which requires a dynamic approach. By passively moving the interphalangeal joint, a thin hyperechoic structure covering the ulnar collateral ligament becomes apparent. This becomes crucial in identifying a tear in the ulnar collateral ligament.
A dynamic evaluation involves inducing slight valgus stress across the metacarpophalangeal (MCP) joint. This stress maneuver aids in widening the joint, potentially assisting in fluid visualization within a ligament tear.
Understanding the intricate details of ultrasound evaluation for gamekeeper's thumb or skier's thumb is invaluable in clinical practice. From proper probe placement to identifying critical bone landmarks and assessing dynamic changes, each step contributes to an accurate diagnosis and effective treatment planning.
Contact Gulfcoast Ultrasound Institute at
111 2nd Ave NE, #800
St. Petersburg, FL 33701