4. Dorsal view

Figure 1. Dorsal view, transverse plane. ST: semitendinosus muscle tendon

Transverse ultrasound section of the posterior medial part of the knee showing the semitendinosus muscle tendon (ST) as an oval structure positioned superficially on the semimembranosus muscle, which forms the broader muscular base of this projection. This typical spatial arrangement allows clear identification of the medial portion of the hamstrings in the popliteal area. This projection is important as a reference point for tracking the medial hamstrings and for evaluating their tendinous and muscular lesions. Clinical note: the characteristic appearance referred to as "cherry on cake" facilitates rapid sonographic orientation and localization of the semitendinosus muscle tendon.

Figure 2. Dorsal view, transverse plane. SM: semimembranosus muscle tendon, ST: semitendinosus muscle tendon

Transverse ultrasound section of the posterior medial part of the knee showing the area between the semimembranosus muscle tendon (SM) and the medial head of the gastrocnemius muscle. In this projection, the semitendinosus muscle tendon (ST) is also visible, along with the deep bony contour of the femur as the main anatomical landmark. This projection is essential for evaluating the popliteal region and particularly for detecting Baker's cyst, which typically appears as a fluid collection between the semimembranosus muscle tendon and the medial head of the gastrocnemius muscle.

Figure 3. Dorsal view, transverse plane. T: tibial nerve, P: common fibular nerve

Transverse ultrasound section of the posterolateral part of the knee in the popliteal fossa region. In this projection, the biceps femoris muscle is visible as an important muscular landmark, near which the common fibular nerve (P) can be visualized as an oval structure with typical fascicular appearance, branching laterally, while the tibial nerve (T) continues more medially. This projection is crucial for evaluating sciatic nerve bifurcation and for detecting entrapment, compression, or traumatic injury of peripheral nerves in the posterolateral knee region.