Thread by @BadgleyLaurence

CRPS is devastating and medical consensus is that cause is unknown. Based on my clinic experience, I will offer my opinion about the etiology of Chronic Regional Pain Syndrome (CRPS).

https://twitter.com/adfurlan/status/1157668521771487233

As stated in the video, CRPS usually afflicts one extremity & among signs and symptoms there are dysautonomias: paresthesias & vascular changes. Obviously, the autonomic nervous system is affected.

In those with CRPS of the upper extremity I have examined, a constant finding has been premonitory Thoracic Outlet (TO) Syndrome (TOS); whereat the brachial neurovascular bundle & contiguous autonomic nerves to arm are intermittently impinged within the TO.

For many years, until recently, the Thoracic Outlet (TO) was considered to be amongst the Scalene muscles. Over the last 20 years, I believe evidence has shown that the true TO is the ~1.0 cm dimension under the proximal clavicle.

The true TO is space between underside of clavicle & top of adjacent underlying first rib. When arm is abducted, distal clavicle usually raises maintaining an open TO. Attendant with certain shoulder disorders TO closes; impinging neurovascular contents of TO.

Thoracic Outlet (TO) closure occurs associated with: ligament disorders of acromio-clavicular joint, sloped shoulder, ipsilateral lower shoulder, atrophic ipsilateral Superior trapezius & isolated hypertropic hyperdynamic Pectoralis minor muscle.

Hypertropic hyperdynamic Pectoralis minor muscle can also arise secondary to an hypertrophic & hyperdynamic ipsilateral Superior trapezius (oft from chronic head tilt; possibly secondary to functional scoliosis &/or sacroiliac joint dysfunction).

Overhead pitchers oft develop TOS due to atrophy of ipsilateral Superior trapezius & hypertrophy of opposing Pectoralis minor that opposes this S. trap.; related to biomechanics of using arm as a catapult (my own analysis); having examined major league pitchers.

During overhead pitch the arm opposite throw arm is forcefully thrown downward to windup the upper body; causing Sup. trap. on this side to become dominant over Sup. trap of the throw arm.

Thoracic Outlet disorders can variously derive from morphological inheritances, hypermobility disorders & repetitive stress disorders of soft tissues of the shoulder girdle ....

These disorders also derive from mechanical shoulder injury, surgery, prolonged shoulder splinting, & crossed muscle syndromes of the shoulder girdle (after V. Janda).

When distal clavicle (18 cm long) moves abnormally few mm inferiorly during arm abduction, geometry shows Thoracic Outlet (TO) closes about 30%. This closure impinges autonomic nerves within TO. Repetitive soft tissue impingement is painful & injurious to neurovascular tissues.

TOS cannot be detected by any known imaging study because soft tissues are radiolucent & images are two dimensional & static. Cinematic images do not exist. Even fluoroscopy is 2-D.

Way to diagnose TOS: progressively abduct suspect extremity while palpating radial pulse. At a reproducible degree of abduction, radial pulse
extinguishes....

If arm is shifted a few degrees superior/inferior back & forth a station of elevation will be located whereat radial pulse goes from palpable to non-palpable.

Simultaneous auscultation under proximal 1/3 of clavicle oft finds a bruit of the subclavian artery impingement. Doppler ultrasound study of subclavian artery with Adson’s maneuver confirms these findings; with which to pursuade other doctors.

Many doctors disbelieve in TOS because they do not know how to use sensitive touch & hearing to distinguish soft tissue spasms, pulse, bruits & skin temp changes during functional shoulder exams. They are not aware of Doppler studies to inform re: subclavian artery impingement.

IMO, significant portion of Neurologists disbelieve reality of TOS. Reason seems their favored diagnostic tool, Nerve Conduction Tests (NCT), fails to distinguish TOS; because NCT shows + with nerve cell death. In TOS, nerves do not die; just pained from recurrent impingement.

Diagnosis of TOS requires the most sensitive instrument known, a thoughtful analytical doctor with trained sensitive touch to evaluate soft tissues (including arterial pulsation) as the shoulder is examined while functioning in real time.

Best solution for CRPS is early diagnosis followed by dedicated physical therapy guided by physical findings. Biofeedback, massage, Aquatherapy, muscle re-education & Prolotherapy are all tools, but must be used rationally & in proper sequence based on findings.

CRPS of lower extremity has similar etiology to arm; neural impingements occur at level of pelvic girdle sacroiliac joints (presacral plexus), or knee, or ankle. Similar diagnostic & therapeutic principles apply. Loose joints must be repaired & muscles need relaxation/retraining

CRPS disorders are afflictions attendant with having two girdle systems in humans: shoulder & pelvic. Knee & ankle joint instabilities commonly follow upon pelvic girdle instabilities. Persons with Hypermobility Spectrum Disorders (#HSD) are prone to CRPS.

In researching TOS in chronically pained shoulders (N=100), I did several mini-experiments to detect TO impingements; employing static weights applied to forearm & SaO2 & temperature gages attached to fingers.

During arm & clavicle ranges of motion these instruments reproducibly reflected autonomic changes.

One thing I learned is that the acromio-clavicular joint is a universal joint & under delicate control of several shoulder muscles. Injury & deviant function of this tiny joint has profound effects on neurovascular contents of the true Thoracic Outlet.

Unfortunately, time & lucre deficits have delayed publication of my data.

A point to be made is this: Since the medical profession knows not the cause of CRPS, it knows not the cure. Lack of knowledge of a cure correlates with inability to state, with any certainty, that proper cure cannot be applied to advanced cases.

Finally, doctors should stop serial extremity operations unless all else has failed for extremity disorders. Once an extremity has been injured, whether accidentally or by surgery, all efforts need to be made expeditiously to reconstitute soft tissue tone & function.

As little as two weeks of disuse of muscle groups leads to profound loss of soft tissue tone & function, and loss of proper function of contiguous joints. Onset of pain attendant with these circumstances can incite additional splinting, disuse, & atrophy.

In some aspects, CRPS might considered to be a self-perpetuating disorder. The theories, postulations & observations reported above are mostly my own inventions.