1. Peritendinitis crepitans is the result of exhaustion of particular muscle groups by unaccustomed and unremitting toil, or by continued, usual, accustomed labor following direct trauma.
2. Pathologically it is characterized by glycogen depletion of muscle, acute degenerative muscle changes, thrombosis of venules, retention of lactic acid, oedema, and local increase in pH to a relatively high acid reaction. Interstitial deposits of masses and of clumps of fibrin give rise to the distinct diagnostic clinical sign of crepitation in the soft parts involved.
3. The primary change is without doubt in the muscle, the other factors developing secondary to muscle exhaustion.
4. The disease is not connected with the synovial tendon sheaths, and is not a "synovitis sicca".
5. Adequate, complete immobilization of joints and portions of the extremity moved by the affected muscles and tendons is the logical and most effective treatment. Baking, heat, massage, elastic compression, or strapping are makeshifts and are utilized without a true understanding of the pathological changes existing.