Spring ligament consists of all EXCEPT:
**Core Concept**
The spring ligament is a fibrocartilaginous structure that plays a crucial role in supporting the medial arch of the foot. It forms the medial (inner) aspect of the foot's arch and helps to distribute pressure evenly.
**Why the Correct Answer is Right**
The spring ligament is composed of the plantar calcaneonavicular ligament, which connects the calcaneus (heel bone) to the navicular bone, and the plantar interosseous ligament, which connects the calcaneus to the sustentaculum tali (a bony projection on the calcaneus). These ligaments work together to provide support to the medial arch of the foot.
**Why Each Wrong Option is Incorrect**
**Option A:** The deltoid ligament is a strong ligament on the medial aspect of the ankle joint, but it is not a component of the spring ligament. It provides stability to the medial aspect of the ankle joint.
**Option B:** The plantar fascia is a thick band of connective tissue that runs along the bottom of the foot, providing support to the arch. It is not a component of the spring ligament, but rather a separate structure that works in conjunction with it.
**Option C:** The plantar calcaneocuboid ligament is a ligament that connects the calcaneus to the cuboid bone. It is not a component of the spring ligament, but rather a separate ligament that provides support to the lateral aspect of the foot.
**Clinical Pearl / High-Yield Fact**
The spring ligament is a common site of injury in individuals who participate in sports that involve running or jumping. It can be damaged due to repetitive stress or sudden trauma, leading to pain and instability in the foot.
**Correct Answer:** D.