1948 Micheli – Fibrosite

This is a simple Italian article titled La fibrosite dolorosa published in a local Italian magazine called Settimana medica from Firenze, Italy. The author is called Prof. Michele Micheli.

He refers to the work of other contemporary authors such as Llewelyn, Stockman, Copeman and Ackerman, Kellgren, and Kelly, among others.

He presents a simple diagram of the most common locations of the fibrositic painful lesions, and the location where to do the novocaine anesthetic injection (according to Micheli, the most effective treatment for the pain management of the chronic fibrositis lesions).


  • Headache, occipital, the superior nuchal line, near the vertex of the angle made by sternocleidomastoid with the trapezium, angle whose floor is formed by the splenium of the head.
  • Shoulder pain, radiating down to the deltoid insertion: center in the supraspinatus fossa.
  • Pain in the forearm and extensor mass at the radial neck.
  • Pleurodynia: intercostal muscles, usually near the anterior axillary line.
  • Abdominal pain: margin of the erector of the spine, or margin of the rectum of the dome.
  • Low back pain, of the spine erector, or large gluteus muscle in the sacroiliac region.
  • Sciatic pain: center of the great gluteus, or tendons near the union with the muscle.
  • Painful knee: deep tissues of the tubercle region of the large abductor.
  • Painful calf: gives way to local care with difficulty; temporary relief with infiltration behind the internal condyle of the tibia.
  • Fibrosite of the sole of the foot: apex of the longitudinal arch at the inner edge; little success of local anesthesia.
  • Cramp of the foot: oblique head of the adductor of the big toe, near the center of the 1st metatarso.


Prof. Michele Micheli

(From Firenze, Italy)

He relates the term “fibrosite” or fibrositis to what the English authors used to name a group of painful entities that have been named as sciatica, low back pain, periarticular pain, bursitis, myalgia, and neuralgia but somehow the etiology is unclear.

He defines fibrositis as an inflammatory reaction non-supurative of the connective tissue of the muscles, tendons, periarticular, and perineural tissues.

Sometimes it presents in a diffuse form that can affect the mobility of the patients severely. It usually presents between the forties and the sixties, especially among women, and after the sixties in men.

The SCIATIC and LUMBAR regions are the most common locations of the fibrositis.

About etiology of the fibrosite

 The following factors have been related to the development of fibrositis:

  • -Focal infections
  • -Diet or nutrition factors
  • -Endocrinopathies (like hypothyroidism)
  • -Metabolic diseases (gout, hepatic disease)
  • -Trauma
  • -Fatigue
  • -Certain kinds of work
  • -The weather (temperature, atmospheric pressure, climatic dermatosis)
  • -Hereditary tendency

About the etiopathogeny of the fibrosite

Several entities have been related to be the cause of primary development of the fibrositic syndrome.

 Infections and intoxications: It has been related to LOCAL INFECTIONS such as tonsillitis, gingivitis or dental abscess. Also after a vaccination. Also after overmuscular work, then it is a more local affection. It has also been related to the acute rheumatism, the influenza, and the colitis. The precipitant factors could be the coldness, the humidity, the muscular fatigue, the indigestion, and the fever.

Filtrable viruses: This relation with certain viruses was due to the observation of “epidemic myalgias” (“torticollo epidemico, epidemie di reumatismo della spalla”). Also by the fact that after blood transfusion, the myalgia was transmitted. Micheli wonders if there could be a specific virus that could cause the fibrositis nodular formations.

Circulatory deficiencies: It has also been related to a lack of adaptation of the CAPILLARIES to the atmospheric changes, with accumulation of metabolites. Also to the accumulation of “fattore P” that is a product after muscular activity, it may be accumulated if there is a deficiency of the circulation. He also mentions the possible role of histamine.

Postural factors: Especially obvious when it is related to certain maintained postures or movements, for example in certain professions.

Psychic factors: Micheli said that it was clear that there would be a psychic factor in the development and maintenance of the fibrosite in certain patients. Many patients related to an emotional disturbance.

-Panniculitis: Subcutaneous fibrositis has similarities to Dercum’s disease and to certain hypothyroidism dysfunctions.

About the histology of fibrosite

 Fibrositis has been characterized by the presence of an exudation (without leucocytes or very few) and nodules that later become organized with fibroblast proliferation and new blood vessels.

At later stages, it presents as a DENSE CONNECTIVE TISSUE that has lost the primitive circulatory vessels that present obliteration.

It should be noticed, however, that the formation that appears as nodules, especially in the muscle, once analyzed microscopically DOES NOT PRESENT ANY CHARACTERISTIC APPEARENCE histologically.

In early stages, it can coexist with a MUSCULAR SPASM around the painful point.

Micheli mentions then (referring to Copeman’s work) that many of the “fibrositic nodules” are fibro-fatty nodules, especially in the back. They can present a LOCAL PAINFUL EDEMA and HERNIATE. In these cases dehydration therapy and local hypertonic injections have helped to give pain relief.

Some authors (he refers to ELLIOT, 1944) related the fibrositis to certain neurophysical factors since some of the nodules resolve after local anesthesia.

Diagnosis and localization of fibrosite

Generally, fibrositis presents as PAIN. Superficial and localized or more deeply located and less localized. It can also present radiated pain. It can be diagnosed clinically by the location of its mechanic characteristics or neuropathic presentation. Also because local injection with novocaine can give pain relief.

It has to be differentiated from the so-called “psychogenic rheumatism”.

The classification from the Bath National Mineral Water Hospital was “intramuscular fibrositis, periarticular fibrositis, bursitis or tenosinovitis, subcutaneous fibrositis, perineuritic fibrositis -brachial or sciatica”.

MICHELI presents the following classification:

-“Intramuscular fibrosite”: Typical from the lumbago. The palpation of the lumbar region is painful. It has to be differentiated from a lesion in the vertebral column.

Fibrositis and bursitis periarticular: It has to be differentiated from the arthritis. It is just painful in a certain area and with certain movements. He mentions especially one common cause: “la spalla dolorosa” or “painful or frozen shoulder”.

Panniculitis: It is the entity that resembles Dercum’s disease, it presents subcutaneous fibrositis especially in the neck, posterior fascia of the arm, internal fascia of the knee. Especially common in hypothyroidism and “hipovaric” women. It accompanies of LOCAL RIGIDITY, cold sensation, hyperesthesia and even local perspiration or cianosis. It can present small fat herniae within the subcutaneous tissue.

Interstitial neuritis: If the fibrositis nodule is close to a nerve trunk, it can present a painful syndrome with paresthesias, hypersensitivity, and radiated pain. Burning sensation with a localized area, worst at night. It can present muscular atrophy and low reflex test.

Brachial neuritis: It is perineural affection of the brachial plexus or of the fascia of it, from the base of the neck and the rhomboid muscle.

Occipital neuritis: Fibrositis of the scalp that can cause intense headache especially at first time in the morning.

Intercostal neuritis: It is a deep not well located pain in the thoracic wall with pleuritic characteristics.

Facial neuritis: Due to fibrositis of the PAROTIDEAL DEEP FASCIA around the VII nerve around the sternomastoideo hole. It can cause facial palsy.

Sciatica: It is one of the most common presentations. It is probably due to the fibrositis of the lumbar or gluteal muscles without direct affection of the sciatic nerve. The injections with novocaine of the painful spot give immediate relief. Sometimes it can be difficult to differentiate the fibrositis form from the TRUE SCIATIC NERVE affection. Fibrositis usually presents as an ACUTE affection.

MICHELLI concluded by saying that the term fibrositis COVERS many painful entities. Sometimes the fibrositis lesion is a primary lesion and other times it is just secondary to a primary lesion that just perpetuates the pain.

Treatment of fibrosite

First of all, the primary cause has to be cured.

In acute phases, the authors recommend:

  • -Rest of the affected part
  • -Salt purge
  • -Lactovegetarian diet with lots of liquid
  • -Analgesia
  • -Local heat
  • -Analgesic cream

In the chronic stage: massage, warm bath, certain diet adjustments -gout, sugar, fat-, drugs as needed (gout, tiroideal or sex hormones). Passive gym.

The best result is obtained by the LOCAL ANESTHETIC INJECTION. Novocaine 0.5-1%, 2-5 cc. It can give temporal o permanent relief. The most difficult part of this treatment is to find the specific point where to inject.


Micheli M. La fibrositie dolorosa. Settimana medica. 1948. 36 (9-13) p 114-8. ISSN: 0037-2917.