This diagnostic radiograph displays two views of a Moovis carpometacarpal (CMC) joint prosthesis implanted in the thumb. The image illustrates a total joint arthroplasty for the treatment of rhizarthrosis (basal thumb arthritis). The prosthetic system consists of two highly radio-opaque components: a threaded metal cup and a medullary stem. The threaded cup is securely fixed into the trapezium bone, while the elongated, tapered stem is inserted into the proximal medullary canal of the first metacarpal. A ball-and-socket articulation is visible between the stem neck and the trapezial cup, mimicking the natural saddle joint anatomy to restore range of motion and stability. The surrounding cortical bone shows clear contrast against the metallic hardware, and the placement indicates proper alignment within the thumb's CMC joint space. This imaging is characteristic of post-operative orthopaedic assessment to verify component positioning and osseointegration.

**Modality:** Magnetic Resonance Imaging (MRI), T1-weighted sequence. **Anatomical Region:** Coronal view of the thumb carpometacarpal (CMC) joint, also known as the trapeziometacarpal joint. **Key Landmarks:** The image clearly delineates the articulation between the distal surface of the trapezium and the proximal base of the first metacarpal. Adjacent carpal bones, including the scaphoid and trapezoid, are visible in the proximal and medial fields. **Visual Features:** - **Osseous Structures:** The saddle-shaped morphology of the trapeziometacarpal joint is visualized. Cortical margins appear sharp with high-signal subchondral bone. - **Joint Space:** The articular gap is well-defined, showing the relationship between the reciprocal concave and convex surfaces of the joint. - **Soft Tissues:** Intermediate signal intensity represents the surrounding capsular ligaments and intrinsic musculature of the thenar eminence. - **Texture:** The image demonstrates high-resolution trabecular patterns within the cancellous bone, characteristic of ex vivo cadaveric imaging. **Clinical Significance:** This high-detail anatomical study is utilized for evaluating joint congruivity, detecting subchondral changes, and assessing ligamentous integrity in the context of osteoarthritis or mechanical instability of the first ray.

This diagnostic image is an intraoperative fluoroscopic (real-time X-ray) view of the hand and wrist. The field of view focuses on the carpometacarpal region, specifically highlighting the basal joint of the thumb. Visible skeletal anatomy includes the base of the first metacarpal, the trapezium, the scaphoid, and the bases of the second and third metacarpals. Two radio-opaque surgical instruments are present: a curved periosteum elevator positioned superiorly and a straight surgical blade (consistent with a #15 blade) positioned inferiorly. These instruments are shown performing arthrolysis (joint mobilization) of the trapezium. The image demonstrates the spatial relationship between surgical tools and small carpal bones during a trapeziectomy or suspensionplasty procedure for thumb carpometacarpal osteoarthritis. This material is suitable for advanced orthopedic surgical training and demonstrates real-time visualization of joint capsule dissection under fluoroscopic guidance.

**Imaging Modality:** Magnetic Resonance Imaging (MRI). **Anatomical Region:** Oblique view of the first carpometacarpal (CMC) joint of the hand. **Key Landmarks and Features:** - **Primary Structure:** The anterior oblique ligament (AOL), also known as the beak ligament, is visualized extending from the volar tubercle of the trapezium to the volar base of the first metacarpal. - **Orientation:** The image captures an oblique plane specifically angled to isolate the longitudinal fibers of the AOL. - **Markers:** A high-signal external marker is positioned adjacent to the skin surface, corresponding to the anatomical location of the ligament for localization purposes. - **Joint Characteristics:** The saddle-shaped articulation between the trapezium and the base of the first metacarpal is visible. The ligament appears as a low-signal (hypointense) band, providing essential stability to the CMC joint. **Clinical Significance:** This view is utilized to assess the integrity of the primary stabilizing structures of the thumb base. It is critical for evaluating ligamentous laxity, attenuation, or tearing associated with first CMC joint instability or basal joint osteoarthritis.