What Actually Happens With a Chiropractic Adjustment: Inside Your Spinal Column

• Part 1: Spinal Manipulation vs Spinal Mobilization
• Part 2: Inside Your Spinal Column

In this blog series, I will explain in detail what is happening in your spine during a chiropractic adjustment. This second article in the series will detail the changes in your spine that occur during a chiropractic adjustment.

If you are new to chiropractic, you may be curious about what actually happens during an adjustment. Because most adjustments happen on your back or neck, it is hard to see what the chiropractor is doing during an adjustment. However, it is entirely reasonable to wonder what is going on in your body as your chiropractor adjusts it.

As a practicing chiropractor in the Chesapeake region for more than 20 years, I am an expert in the chiropractic adjustment process. In this article, I will explain to you what happens during the adjustment itself.

What Happens Inside Your Spine During a Chiropractic Adjustment?

When you’re lying on the chiropractor’s table, an adjustment may seem like a blink-and-you-miss-it process. However, the adjustment itself has different components which scientists have broken down by the millisecond. Each part of the adjustment process has an important role to play in supporting the biomechanics of your spine and treating spinal imbalance.

Three specific phases make up a chiropractic adjustment: the pre-load phase, the thrust phase, and the resolution phase:

What Happens During the Pre-load Phase of a Chiropractic Adjustment?

During the preload phase, a constant pressure is applied to the joint. This pressure is in the same direction that the chiropractor will eventually thrust the joint. The goal of the pre-load phase is to compress the soft tissues enough that the movement of the joint becomes more predictable. The amount of force applied to the joint during the pre-load phase is called the pre-load force, and this force can vary depending on the part of the spine to which it is applied:

• Cervical spine: The preload force can range from 0 to 39.5 Newtons
• Thoracic spine: The preload force can range from 93 to 185 Newtons
• Sacral spine: The preload force can range from 10 to 166 Newtons

What Happens During the Thrust Phase of a Chiropractic Adjustment?

In the thrust phase, the chiropractor quickly applies extra force to the joint to correct a spinal imbalance. This phase is quick and lasts around 48 milliseconds. As during the pre-load phase, the thrust force can vary depending on the type of chiropractic care you receive and the part of the spine to which it is applied.

During spinal manipulation techniques, the chiropractor applies a high-velocity, low-amplitude force to the spine. This causes cavitation, or a “popping” sound in a joint:

• Cervical spine: The thrust force has an average of 118 Newtons
• Thoracic spine: The thrust force has an average of around 400 Newtons
• Sacral spine: The thrust force has an average of greater than 400 Newtons

During spinal mobilization techniques like NUCCA, no forceful thrusting takes place and no popping sound occurs. Instead, your spine’s alignment is gently corrected based on a precise mathematical analysis of your X-rays. In spinal mobilization, your chiropractor performs graded movements of a precise depth and rate without a sudden thrust.

What Happens During the Resolution Phase of a Chiropractic Adjustment?

In the resolution phase, the chiropractor releases the pressure applied to the joint. This allows the force on the joint to go back down to 0 Newtons.

Overall, the entire adjustment, from pre-load phase through the resolution phase, lasts an average of 102 milliseconds.

What Occurs Inside the Joint During the Chiropractic Adjustment?

During the adjustment itself, the joint is being corrected into its proper position. Chiropractic care uses the principle of joint distraction, in which force is being used to physically separate the surfaces within the joint.

When these surfaces separate, there is now space for the synovial fluid which lubricates the joint. The synovial fluid can then reduce the friction in the joint, allowing an improvement in motion. All in all, the adjustment corrects the structure of the joint. This relieves your pain and leaves you more functional.

Because a joint’s structure is closely related to its function, improvement in the joint’s structure following an adjustment will directly impact your spinal alignment and overall spinal function.