The neck is considered one of the five parts of the spine. It is referred to as the cervical spine and consists of seven vertebrae, which begin at the base of the skull to the top of the thoracic spine. All of the vertebrae in the spine have different shapes based on their functions, and the spine as a whole is curved in opposing directions to keep the body balanced.
A healthy, natural neck has a small lordosis, which is a forward curve. According to the book "Key Poses of Yoga: Scientific Keys Volume II," when you look at the spine from the side, the forward curve of both the cervical spine and lumbar spine are normal. Normal lordosis of the neck helps support the weight of the head and prevents slouching. When you have excess lordosis, the shoulders hunch forward and movement of the neck and head are limited. This can also lead to neck pain and muscle strains of the upper back and shoulders.
Kyphosis is the opposite of lordosis. When looking at the spine from the side, you will see kyphosis, or a backward curve, in your thoracic spine and sacrum. A small amount of natural kyphosis is already a part of your spine to help balance natural lordosis, but cervical kyphosis occurs when the neck begins to actually straighten out or even reverse directions. Cervical kyphosis can occur for several reasons, including degeneration of the vertabrae, trauma, whiplash or compression fractures.
One of the best ways to treat excess lordosis is yoga. Yoga is centered around the health of the entire spine and nearly every pose strengthens and lengthens the spine. Specifically, you should practice poses that open the chest and help keep the shoulders from rounding forward. Poses that lift the neck and lengthen through the front of the neck are best to counteract the effects of lordosis. Poses such as Fish Pose, Locust Pose, and Cobra Pose open up the front of the neck and chest.
Yoga poses that help cervical kyphosis are those that help lengthen the back of the neck, shoulders and upper back. Forward-folding poses are an effective way to open the back of your torso. Those poses include Gorilla Pose, Standing Wide Leg Forward Fold, Seated Forward Bend and Hand to Foot Pose. These poses will help alleviate excess kyphotic curve through the cervical spine and help realign the vertebrae of your neck.