Finger Yoga

RSI: subsynovial connective tissue

Many, though not all of these papers are from the Mayo Clinic. Their findings are in need of further corroboration.

The body's subsynovial connective tissue is found mainly in the carpal tunnel, where it is the most common tissue type.

Carpal Tunnel Syndrome - A Team Approach - Mayo clinic pages - with useful video
Shearing injuries to subsynovial connective tissue possible cause of carpal tunnel syndrome - a popular article on the subject.
Carpal Tunnel Syndrome: The Role of the Subsynovial Connective Tissue
Gliding characteristics of flexor tendon and tenosynovium in carpal tunnel syndrome: a pilot study.
Carpal tunnel syndrome. - a review, mentioning subsynovial connective tissue.
Study Of Flexor Tenosynovium And Carpal Tunnel Syndrome. [Mayo Clinic]
An article about subsynovial connective tissue (SSCT) in Carpal Tunnel Syndrome. [Mayo Clinic]
Flexor Tendon and Subsynovial Connective Tissue Gliding in Carpal Tunnel Syndrome. [Mayo Clinic]
Vascular Pathologic Changes in the Flexor Tenosynovium (Subsynovial Connective Tissue) in Idiopathic Carpal Tunnel Syndrome [Mayo Clinic] | PubMed
High Definition' 3-D Imaging of Mechanoreceptors in Dorsal Radiocarpal Ligament of Human Wrist. [Mayo Clinic]
Changes in the functional structure of the tenosynovium in idiopathic carpal tunnel syndrome: a scanning electron microscope study.
High-resolution ultrasound analysis of subsynovial connective tissue in human cadaver carpal tunnel.
Flexor tendon and synovial gliding during simultaneous and single digit flexion in idiopathic carpal tunnel syndrome.
Permeability of the subsynovial connective tissue in the human carpal tunnel: a cadaver study.
Evaluation of the material properties of the subsynovial connective tissue in carpal tunnel syndrome.
A histological and immunohistochemical study of the subsynovial connective tissue in idiopathic carpal tunnel syndrome.
Morphological changes of collagen fibrils in the subsynovial connective tissue in carpal tunnel syndrome.
Two-Finger Typists at Risk for Carpal Tunnel Syndrome - popular article about Kai-Nan An, at the Mayo Clinic
Evaluation of the material properties of the subsynovial connective tissue in carpal tunnel syndrome.
Relative longitudinal motion of the finger flexors, subsynovial connective tissue, and median nerve before and after carpal tunnel release in a human cadaver model.
Effects of carpal tunnel release on the relative motion of tendon, nerve, and subsynovial connective tissue in a human cadaver model.
The effect of wrist position on the relative motion of tendon, nerve, and subsynovial connective tissue within the carpal tunnel in a human cadaver model.
The Evidence for Repetitive Microtrauma as a Factor in the Etiology of Carpal Tunnel Syndrome: A Study of the Subsynovial Connective Tissue - a presentation by Dr. Peter Amadio of the Mayo Clinic.

More histopathological findings relating to the causes of carpal tunnel syndrome

A few brief notes about the significance of all this:

Though many of these studies refer to carpal tunnel syndrome, the significance of the theory may well be much wider. It reduces the nerve compression that defines carpal tunnel syndrome to a symptom which lies downstream of the damage that really defines the underlying disease.

As far as theraputic interventions and prevention goes, it looks as though one of the take-home messages is likely to be: take extreme care if performing stretching exercises associated with the finger flexors. These appear likely to be much more dangerous than one might intuitively think.

Other theraputic implications: eccentric exercies probably also have low value.

The normal functions of the subsynovial connective tissue appear to involve facilitating gliding movements, and supplying tendon nutrition.

Subsynovial connective tissue is found mostly in the carpal canal. There is also some present in the knee joint.

There are many questions which arise out of these findings. Among them:

• Are the flexor digitorum profundus and flexor digitorum superficialis tendons typically equally affected?
• Many carpal tunnel syndrome patients do eventually recover - what is the histological state associated with that?
• How widely distributed is this pathology in RSI sufferers not diagnosed with carpal tunnel syndrome?
• Assuming some sufferers have this problem without exhibiting carpal tunnel syndrome symptoms, where does pain for those subjects come from?
• Do these findings suggest any new treatment modalities? - e.g. warming up exercises, low-travel input devices.
• Do these findings suggest any existing treatments are contraindicated - e.g. flexor stretching? or of low utility - e.g. eccentric exercies?
• Diagrams suggest the subsynovial connective tissue operates rather like a telescope: is it a telescope that extends in one direction, or both directions?
• Flexor stretching may be a very risky activity, under this hypothesis - what about extensor stretching? The flexor tendons move to their opposite extreme position - though they are slack. Can that also cause damage?
• Since SSCT is implicated in tendon nutrition, what are the side effects on the tendons of SSCT injuries?