View of the thumb that gives the best delineation of 1st carpometacarpal joint is:
- A- PA
- E- AP
- B- Lateral
- C- Oblique.
The best view of the thumb that gives the best delineation of the 1st carpometacarpal (CMC) joint is: (E. AP (Anteroposterior) view).
Here's why:
- PA (Posteroanterior) view:
While a PA view can show the overall outline of the CMC joint, it overlaps the trapezium (carpal bone) with the metacarpal base, making it difficult to clearly visualize the joint space and articular surfaces.
- Lateral view:
A lateral view provides good visualization of the joint capsule and surrounding ligaments, but it doesn't show the articular surfaces in detail due to the overlapping bones.
- Oblique view:
An oblique view can offer some advantages, especially for visualizing specific ligaments like the scaphotrapezial ligament, but it can also distort the joint space and make it challenging to assess the overall joint relationships.
- AP view:
An AP view directly faces the palmar or dorsal aspect of the hand, placing the trapezium and metacarpal base side-by-side and showcasing the joint space and articular surfaces clearly. This allows for better assessment of joint congruency, cartilage integrity, and potential subluxation or dislocation.
Therefore, the AP view is the preferred choice for visualizing the 1st CMC joint due to its clear depiction of the joint space, articular surfaces, and surrounding structures.
Additional Points:
Here are some additional points to consider:
For specific ligamentous details, oblique views might be helpful in conjunction with the AP view.
In some cases, additional imaging modalities like CT scans or MRIs might be necessary for a more comprehensive evaluation of the joint, especially if there's a suspected fracture or ligamentous injury.
