Gepubliceerd op: 07 Oct 2025
Myofascial Continuity: What the Evidence Really Says (and How Clinicians Can Use It)
Short version: the body’s fascia forms real, anatomical links between muscles; functional force sharing across those links likely matters—but not always as much (or as simply) as some diagrams suggest. For physiotherapists and manual therapists, that means: use chains to inform assessment and treatment, but be precise about what’s known, what’s probable, and what still needs proving.
Why this matters for clinical practice
For years, our profession has moved between two extremes: treating muscles as isolated units or—on the other side—assuming “everything connects to everything” through fascia. The latest review by Kalichman synthesizes both anatomical and functional research and lands in a more useful middle ground: some chains are strongly supported by dissection studies, functional force transmission exists in vivo but is context-dependent and variably sized, and fascial tissues themselves may contribute to tension regulation and sensation. That nuanced position helps clinicians choose the right tools at the right time.
What the anatomy shows (robust vs. weaker links)
The review confirms strong anatomical continuity for three well-known chains:
- Superficial Back Line (SBL): plantar fascia ⇄ Achilles ⇄ gastrocnemius/hamstrings ⇄ erector spinae. Multiple dissections show dense connective tissue with no gaps across these transitions.
- Back Functional Line (BFL): latissimus dorsi ⇄ thoracolumbar fascia ⇄ gluteus maximus ⇄ vastus lateralis ⇄ fibularis longus. Again, robust bands—especially via the thoracolumbar fascia—appear consistently.
- Front Functional Line (FFL): pectoralis major ⇄ rectus abdominis ⇄ adductor longus. Continuous fascial sheets link upper and lower body.
Evidence is moderate for the Spiral and Lateral lines (e.g., reliable continuity between IT band and fibularis longus fascia; more variable at the hip). By contrast, the Superficial Front Line lacks cadaveric validation: proposed links such as rectus abdominis ⇄ rectus femoris don’t show consistent continuity. Clinically, that means we should be cautious about over-relying on SFL narratives when explaining mechanisms or choosing remote interventions.
Two additional angles expand the map:
- The ArthroMyoFascial complex describes continuity from skin through superficial/deep fascia and myofascia down to joint-level “arthrofascia,” supporting the idea that forces and sensations can integrate across a joint region—not just through tendons.
- A proposed neck–eye myofascial continuum (occipitofrontalis/temporalis ⇄ galea aponeurotica ⇄ orbicularis oculi) suggests potential links relevant to oculomotor control and some headache/neck presentations—but the evidence base is small, so keep it as a hypothesis, not a doctrine.
What the function shows (epimuscular myofascial force transmission)
Functionally, we care about epimuscular myofascial force transmission (EMFT)—the idea that forces can spread beyond the myotendinous unit via fascial networks. The review’s bottom line:
- In vivo human studies show context-dependent force sharing. Examples include co-activation/kinetic effects spanning hip, knee, and ankle (e.g., gluteus maximus to fascia lata during hip extension; ankle dorsiflexion altering knee kinetics). These studies tend to be modest in size and variability, so treat the magnitude estimates with caution.
- In vitro/animal data suggest fascia can transmit a non-trivial share of force (estimates up to ~30%), but we don’t have equally solid numbers for living humans across tasks and joint angles. Translation: EMFT matters, but the exact “how much” depends on context (load, position, tissue state).
- Fascial tissues show contractile behavior (myofibroblasts) and are well innervated with mechanoreceptors and nociceptors—relevant for proprioception, pain, and potentially baseline tension regulation. That gives us plausible mechanisms for why manual and movement inputs can change symptoms without huge structural changes.
A useful clinical implication: knee-angle dependent calf–hamstring interactions have been observed with ultrasound—another reminder that chain effects can “switch on/off” with joint position. Your assessment and exercise setup should respect that.
Turning evidence into practice
Below is a pragmatic, evidence-aware way to use chains without magical thinking.
1) Assessment: test the chain, not just the link
- Combine local tests (length/strength, symptom modification) with positional chain tests (e.g., alter ankle dorsiflexion while monitoring knee/hip mechanics and pain; load lat dorsi while assessing contralateral glute function). Look for repeatable, position-specific changes.
- Use palpation/US-informed reasoning for suspected fascial densifications, but anchor decisions in functional change rather than “feel.” The ArthroMyoFascial lens can help you consider skin–fascia–myofascia–joint interactions without over-attributing.
2) Exercise: load the line, then localize
- Start with chain-biased movements (e.g., BFL patterns: contralateral lat pull + ipsilateral hip extension; SBL patterns integrating ankle/knee/hip/spine). Progress by fixing one region and biasing force flow through another to refine motor control.
- Use positional levers (knee angle, trunk inclination, foot position) to dial up or dampen chain interactions. If your test shows a knee-angle dependency in SBL behaviors, program that angle into early sets and explore transfer later.
3) Manual therapy: target plus transfer
- Apply regionally relevant techniques (e.g., superficial posterior chain in persistent hamstring/low-back presentations) but pair them with movement to consolidate any proprioceptive/tension changes. Early RCT-level signals suggest remote myofascial inputs can influence pain and elasticity in chronic LBP—don’t oversell it, but don’t ignore it either.
- For joint-centric pain, consider joint-region fascial mobilizations (ArthroMyoFascial perspective) when typical segmental approaches stall—again followed by task-specific exercise.
4) Education: mechanism honesty builds trust
- Be clear that some chains are well-validated anatomically, others are partial or unproven, and functional effects vary with position and load. Patients appreciate straight talk more than certainties that unravel later.
Where the model can go wrong (and how to avoid it)
- Over-generalizing: Assuming every complaint maps neatly onto a chain risks chasing noise. Anchor to observable change: if a chain-based test doesn’t modify symptoms or performance, don’t force the narrative.
- Ignoring context: EMFT effects are task- and position-specific; what you see at rest may disappear (or appear) under load. Program with deliberate positions/angles.
- Mechanism inflation: Fascial contractility/innervation is real, but effect sizes for manual techniques in vivo are often modest. Use manual therapy to open a window; exercise and exposure keep it open.
Key takeaways for clinicians
- Use the validated chains first (SBL, BFL, FFL) when you need a chain-level hypothesis; treat SFL claims cautiously.
- Test for positional dependency (e.g., knee angle in posterior chain). Program those specifics.
- Pair manual with movement to harness both sensory and mechanical pathways.
- Educate with nuance—patients handle complexity better than we fear.
- Stay evidence-led, not diagram-led. When a chain hypothesis fails your tests, pivot.
Limitations and future directions
We still need larger, controlled in-vivo trials quantifying EMFT under real movement conditions, and advanced imaging (e.g., magnetic resonance elastography) to visualize strain propagation. Expect the field to refine which links truly matter for different tasks (walk/run/jump) and populations (e.g., persistent pain, post-op, athletes). Until then, we practice in the “grey”—but smarter, with better maps and measurement.
References (selected within text)
All statements above are drawn from Kalichman’s 2025 narrative review, which synthesizes anatomical dissections, biomechanical evidence, and clinical implications for myofascial continuity and EMFT.
Myofascial continuity: Review of anatomical and functional evidence Leonid Kalichman,
Journal of Bodywork and Movement Therapies
Volume 45, December 2025, Pages 569-575