01 / Nasal & sinus congestion

Internal Bone Blockages Explained

Cranial Solutions2 December 20256 min read

A constant feeling of nasal blockage without excess mucus is frequently associated with physical alignment shifts in the deep internal bones of your nose. Deep inside the nasal vault, three main structures meet: the flexible septal cartilage at the front, the thin ethmoid bone plate at the top, and the plough-shaped vomer bone at the bottom.

Visit the Nasal & Sinus Congestion page

If early birth strain, facial injury, or upper jaw narrowness causes a minor tilt or spur at this bone junction, the narrowest passage inside your nose - the Minimal Cross-Sectional Area (mCSA) - shrinks. Under fluid dynamics principles, this physical narrowing turns smooth, quiet air movement into noisy, turbulent eddies, creating high breathing resistance that sensory nerves register as chronic congestion.

Comparison: Smooth Airflow vs. Turbulent Airflow Dynamics

Minimal Cross-Sectional Area (mCSA)

Wide, aligned nasal vault (laminar flow): Greater than critical threshold (> 0.37 cm²); open physical pathway.
Narrow, obstructed nasal vault (turbulent flow): Compressed below critical threshold (< 0.37 cm²) due to bony spurs or tilts.

Air movement pattern

Wide, aligned nasal vault (laminar flow): Smooth, parallel air streams (laminar flow) gliding quietly through nasal meatuses.
Narrow, obstructed nasal vault (turbulent flow): High-velocity, chaotic eddies (turbulent flow) creating mechanical resistance.

Work of breathing

Wide, aligned nasal vault (laminar flow): Low physical effort; effortless, silent nasal inhalation day and night.
Narrow, obstructed nasal vault (turbulent flow): High physical effort; sensory nerves register airflow turbulence as "stuffy nose".

Mucosal conditioning

Wide, aligned nasal vault (laminar flow): Air is properly warmed, filtered, and humidified before reaching lungs.
Narrow, obstructed nasal vault (turbulent flow): Incomplete conditioning; dry air triggers secondary mucosal irritation.

Primary care need

Wide, aligned nasal vault (laminar flow): Maintenance of natural, open airway space.
Narrow, obstructed nasal vault (turbulent flow): Restoring physical space across the internal vomer-ethmoid junction.

Airflow dimension	Wide, aligned nasal vault (laminar flow)	Narrow, obstructed nasal vault (turbulent flow)
Minimal Cross-Sectional Area (mCSA)	Greater than critical threshold (> 0.37 cm²); open physical pathway.	Compressed below critical threshold (< 0.37 cm²) due to bony spurs or tilts.
Air movement pattern	Smooth, parallel air streams (laminar flow) gliding quietly through nasal meatuses.	High-velocity, chaotic eddies (turbulent flow) creating mechanical resistance.
Work of breathing	Low physical effort; effortless, silent nasal inhalation day and night.	High physical effort; sensory nerves register airflow turbulence as "stuffy nose".
Mucosal conditioning	Air is properly warmed, filtered, and humidified before reaching lungs.	Incomplete conditioning; dry air triggers secondary mucosal irritation.
Primary care need	Maintenance of natural, open airway space.	Restoring physical space across the internal vomer-ethmoid junction.

Anatomy of the Internal Nasal Tri-Junction

The Three Deep Structures

The wall down the middle of your nose (the nasal septum) is not just cartilage - it is a semi-rigid structure made of three distinct anatomical parts that meet at a central tri-junction:

01The Quadrangular Cartilage (Front): the flexible cartilage at the front of your nose that supports the nose tip.
02The Ethmoid Bone Plate (Top-Back): a delicate vertical projection of bone extending downward from the roof of the nasal cavity.
03The Vomer Bone (Bottom-Back): a sturdy, plough-shaped bone that forms the lower back portion of the septum, resting upon the roof of the mouth (maxillary crest).

The "Hourglass" Fluid Dynamics Effect

In fluid mechanics (Bernoulli's principle of pipe flow), the rate of air movement through a pipe is governed by its narrowest point. Inside the human nose, this bottleneck is called the Minimal Cross-Sectional Area (mCSA).

When internal bones are aligned: air passes through the mCSA in smooth, parallel streams.
When internal bones are tilted or spurred: if the vomer or ethmoid bone tilts slightly off-centre, the mCSA shrinks. Once the area drops below 0.37 cm², smooth airflow breaks down into high-velocity turbulence. This air swirling creates high friction against the nasal walls, making your nose feel blocked even when there is no mucus present.

Why Medications Cannot Correct Internal Bone Misalignment

Many patients spend years trying over-the-counter and prescription chemical remedies for "stuffy nose" symptoms without realising their blockage may be structural:

Nasal steroid sprays: sprays reduce soft tissue swelling in the mucosal lining, but they cannot shift or alter the physical position of the vomer or ethmoid bones.
Antihistamines: antihistamines block allergic histamine responses, but they do not widen a narrowed bony channel.
Saline rinses: saline flushes wash away dust and thin out mucus, but liquid passes right around a bony spur without changing the narrow mCSA bottleneck.

When the primary cause of airflow resistance is physical bone crowding at the tri-junction, structural space must be re-established.

To learn how structural narrowing affects airflow and sinus drainage, visit our Nasal & Sinus Congestion page.

How Non-Surgical Endonasal Inflation May Help

For individuals seeking a non-surgical option to restore physical breathing space, Cranial Facial Release (CFR) / Nasal RX provides targeted physical medicine care.

Endonasal Inflation Mechanism

Step 1: Gentle placement of a small inflation catheter into the nasal passage.
Step 2: Rapid, controlled 1 - 2 second micro-inflation applying outward pressure.
Step 3: Mobilisation of restricted sphenovomerine & palatine facial sutures.
Step 4: Mechanical expansion of the minimal cross-sectional area (mCSA).
Step 5: Restoration of smoother, laminar nasal breathing.

Endonasal inflation uses brief, controlled micro-inflation within the nasal meatuses. This applies outward fluid pressure against the lateral nasal walls, helping mobilise micro-restricted facial sutures (sphenovomerine and palatomaxillary) and decompressing the deep vomer-ethmoid junction. Widening the mCSA aims to restore smooth, laminar airflow and reduce chronic breathing turbulence.

Can internal nose bones really be crooked if my nose looks straight on the outside?

Yes. The outside of your nose is shaped primarily by front cartilage and nasal bones, whereas the vomer bone and ethmoid plate sit deep inside the central face. You can have a straight external nose while having significant bone crowding deep inside the nasal vault.

Why does my nasal blockage switch from one side to the other?

Nasal blockage switching sides is part of the natural "nasal cycle", where autonomic nerves alternate blood flow between the left and right turbinates every few hours. However, if your deep internal bones are already narrow, normal swelling during the nasal cycle can close off the narrower side, making the blockage feel severe.

How does endonasal inflation differ from septoplasty surgery?

Septoplasty is an invasive surgical operation that cuts, shaves, or removes deviated cartilage and bone under general anaesthesia. Endonasal inflation (CFR / Nasal RX) is a non-surgical physical procedure performed in-clinic. It uses brief inflation to gently mobilise tight facial sutures and expand internal passages without cutting or removing tissue.

Read more about roof-of-mouth shapes, swollen nasal tissues, and what to expect from Nasal RX on our Nasal & Sinus Congestion page.

References

01Garcia GJ, Rhee JS, Poon CS, Elad D. The relationship between nasal resistance to airflow and the airspace minimal cross-sectional area. J Appl Physiol. 2016;120(11):1388-1398.
02Costa CM, Costa JG, Saramago AC, Mattos CT, Vilella BS, Vilella OV. Hyperextension of the head versus cervical vertebrae morphology in mouth and nasal breathers. Rev Cient CRO-RJ. 2021;6(1):26-36.
03Saine A. Who can benefit from the Bilateral Nasal Specific Technique? A clinical perspective. J Clin Chiropr Pediatr. 2023;23(1):12-24.
04Gibson J. Discover the benefits of NasalRX (Cranial Facial Release) in Auckland. Musculoskeletal Solutions Clinical Guide. 2025.

Learn how our non-surgical endonasal protocol is used to evaluate suitability for conservative management, and how cranial base structural mechanics guide an individual care plan.