From a hydrated disc to a fused segment: what the curve, the facets and the disc pump do at each step
Eileen Durfee's Spinal Fitness book describes cervical disc degeneration in 5 stages and calls the progression a force story: each stage is defined by the state of the cervical curve, the load on the facet joints and the compression-decompression pump that feeds the disc.
The book opens the stages with a statement of method: disc degeneration is often described as if it were simply age, but mechanical environment matters, and if the curve is lost and the pumping action is impaired, the disc is placed under conditions that encourage progressive breakdown. The pumping action is the book's disc nutrition model. Intervertebral discs are living tissues that need nutrients and need waste products removed (Chapter 4); after early adulthood, the book states, discs rely heavily on mechanical motion to circulate nutrients inward and remove metabolic waste outward, a process it calls essentially osmotic.
Compression squeezes fluid out of the disc, and decompression draws fresh fluid back in. In the cervical spine, the alternation comes from the floating mechanism: in lordotic alignment, the angled facet joints split force so that part of it stabilizes the joint and part lifts the vertebra slightly, partially unloading the disc during normal head and neck movement. The equipment for this work is in the Creatrix spine alignment stretches and exercises collection.
| Stage | Cervical curve | Disc and pump | Facet joints and segment |
|---|---|---|---|
| 1 of 5: Healthy disc, hydrated | Good curve, protective geometry | Floating mechanism active; disc floats and pumps; healthy hydration | Appropriately loaded |
| 2 of 5: Early degeneration, loss of hydration | Curve reduced | Pumping action impaired; early loss of hydration; mild reduction in disc height | Begin absorbing compressive forces they were not designed to carry continuously |
| 3 of 5: Advanced degeneration, disc collapse | No upward shear component to decompress the joint | Constant compression; nutrient supply compromised; disc height reduced | Facet overload; early arthritic changes |
| 4 of 5: Osteoarthritic changes | Curve restoration can reduce compressive loading | Disc space severely narrowed | Bone-on-bone changes; arthritic facets; adjacent segments begin compensating |
| 5 of 5: Fusion of segment | Overall curve restoration may reduce adjacent-level stress | Complete loss of motion at the fused segment | Bony fusion; adjacent segments compensate |
Stage 1 of 5: Healthy Disc, Hydrated. In the first stage, the disc remains intact and the cervical curve maintains its protective geometry, the floating mechanism is active, and each small movement of the head creates alternating compression and decompression across the disc, driving fluid exchange and keeping the nucleus pulposus hydrated. Nutrients reach the inner cells of the disc through this pumping action, waste products are cleared, and the facets are appropriately loaded.
Stage 2 of 5: Early Degeneration, Loss of Hydration. In the second stage, the cervical curve begins to flatten and the upward shear component at the facet joints weakens; the floating mechanism is impaired but not yet lost. Hydration begins to decline as the pumping action is reduced, the disc gradually loses some of its ability to recover between loading cycles, and disc height may decrease slightly as the nucleus loses fluid volume. The book lists the signs at this stage as mild or intermittent: occasional stiffness, tightness, headaches or fatigue.
Stage 3 of 5: Advanced Degeneration, Disc Collapse. In the third stage, sustained compressive loading has collapsed the disc space significantly, and without the upward shear component the disc is subjected to more constant, unrelieved compression throughout the day. Nutrient supply to the inner disc cells is severely compromised, the nucleus pulposus begins to lose structural integrity, and the facet joints, now carrying load beyond their intended role, begin to show early arthritic changes. The book lists more frequent neck pain, stiffness, radiating symptoms, reduced range of motion and recurring flare-ups at this stage.
Stage 4 of 5: Osteoarthritic Changes. In the fourth stage, bone-on-bone changes are established features of the joint. The disc space is severely narrowed, the facet joints have undergone arthritic remodeling, and the book names chronic inflammation, persistent pain, reduced motion and adjacent segments that begin compensating. The book describes many of these changes as structurally irreversible and states that restoring the cervical curve can still reduce compressive loading on the remaining disc and joint tissue and improve the mechanical environment. Its stated goals at this stage: reduce irritation, improve available motion, unload what can be unloaded, and protect the segments above and below the damaged joint.
Stage 5 of 5: Fusion of Segment. In the fifth and final stage, the vertebrae have fused together as the body attempts to stabilize the damaged joint by eliminating motion entirely. Mechanical work on the fused segment itself is limited by the absence of motion, while the segments above and below retain mobility, and the book states that restoring the overall cervical curve can still reduce the load placed on those adjacent levels. Its summary for this stage is that the goal shifts to protecting what remains of spinal motion, and its system-wide caution in Chapter 9 is that naturally or surgically fused segments cannot be reshaped.
The book compresses the progression into 1 line per stage. In the first stage, the disc remains intact and the pumping action is active. In the second, the curve reduces and hydration begins to decline. In the third, constant compression collapses the disc space and overloads the facets. In the fourth, bone-on-bone changes and arthritic remodeling of the facet joints become established. In the fifth, the body eliminates motion entirely by fusing the segment.
The book's central claim about the sequence is that it is mechanically influenced: restoring cervical lordosis, even partially and even in a spine that has already begun to lose disc height, can improve the mechanical environment by reducing constant compression, reintroducing motion where motion remains possible, and protecting adjacent segments. The book separates that from symptom change. Pain may decrease after rest, medication, massage, adjustment, therapy or time away from activity, but if the curve remains lost and the disc stays in a poor mechanical environment, the underlying force problem remains, which the book gives as the reason symptoms often return.
In the cervical spine, the book defines resolution as restoring the curve, improving control, reducing forward-head leverage and re-establishing as much healthy disc pumping as possible. Effective head load at each head position is covered in the neck-load figures and the Neck Flexion nod.
Step 4 is Neck Flexion, which the book states restores cervical curve and reduces whole-spine compensation from forward head posture. Method B uses the Neck Shaper for consistent resistance once the nod is learned with bare hands. The beginner dose is 6 repetitions per session, 6 sessions per day, with strain and no pain, progressing to 10 reps when 6 no longer create muscular strain; advanced maintenance is 6 to 10 reps every hour, only if symptom-free, and the athletic progression builds toward 15 to 20 reps per session. The Chapter 11 Desk Standard spreads Neck Flexion across a workday: a 2 to 4 minute prime of 6 reps, by hand or with the Neck Shaper, at the start of the day; micro-breaks of 10 to 30 seconds every 45 to 60 minutes with 2 to 3 Neck Flexion reps; and a 15 to 20 minute decompression at home at the end of the shift, 25 Spinal Twist reps followed by Neck and Back Shaper roll rest.
Step 5 is the Spinal Twist and supported rest. In the book's model, the twist helps the center of the disc behave more fluidly for a short window, and the supported rest that follows encourages the spine to settle toward improved curvature while muscles downshift out of guarding. The dose is 25 seated twist reps, then 18 to 20 minutes on the Neck and Back Shaper rolls, no longer; the book caps the rest because longer sessions can cause the nervous system to lose tension in ways that may increase instability.
The book's screen in Chapter 17 decides the starting step. At high irritability, with high muscle tone, swelling or severe guarding, it begins with Step 5 only and re-screens after 2 to 3 sessions; when the screen shows significant forward head posture with a relatively functional lumbar region, it begins with Step 4. The book states that posture screening is a coaching tool, not a diagnosis.
Chapter 15: you should feel muscular strain, but not pain. During the exercise, pain, numbness, tingling, dizziness, visual changes or headache spikes are stop-signs; reduce intensity immediately and seek appropriate medical evaluation. Never force range of motion, and do not shove the face or neck forward.
The Neck Shaper Kit carries the Neck Flexion resistance; the Neck and Back Shaper set holds the cervical and lumbar curves during supported rest.
Practitioner Eileen Durfee, NBS (Nutritional Balancing Science), NASM-CPT — wellness educator, inventor, author, and a Nationally Certified Spinal Fitness Specialist.
Dr. John S. Scherger (1950-2016), my chiropractor and mentor, was the first person to show me that the human body operates according to mechanical laws - that it is not random, but governed by principles that can be understood, measured, and improved. That realization transformed how I approached pain, posture, movement, and performance, and it continues to guide the work shared in my book.
From the close of the 5 stages in Chapter 4: "The progression from a healthy hydrated disc to fusion is not merely a list of medical findings. It is a force story."
Our Facebook group is free to join for questions about any of the 5 steps in the Spinal Fitness system.
Loss of the cervical curve, which weakens the upward shear component at the facets, impairs the floating mechanism and leaves the disc under more constant compression with less pumping.
The book states that the progression is not simply aging; it is influenced by the force environment.
Many changes are structurally irreversible, and restoring the cervical curve can still reduce compressive loading on the remaining disc and joint tissue and protect the segments above and below.
The book states that fused segments cannot be reshaped. The focus moves to the segments above and below, where restoring the overall curve may reduce adjacent-level stress.
The Neck Shaper for Neck Flexion (Step 4) and the Neck and Back Shaper rolls for the 18 to 20 minute supported rest after the Spinal Twist (Step 5).
Published October 10, 2026 • Updated October 10, 2026
By Eileen Durfee, Nationally Certified Spinal Fitness Specialist, NASM-CPT, and author of the Spinal Fitness book.
More from Eileen Durfee
Eileen's free guide, Is Your Posture Aging You?, on EileenDurfee.com
This article is for educational purposes only. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease. Nuco Enterprise Solutions LLC.
