Endocrine, nutritional, and metabolic diseases (E00-E90).
- Diabetic polyneuropathy – damage to multiple nerves (polyneuropathy) that occurs as a complication of existing diabetes mellitus.
- Electrolyte disorders (blood salt disorders), unspecified:
- Hypocalcemia (calcium deficiency).
- Hypomagnesemia (magnesium deficiency)
Skin and subcutaneous (L00-L99)
Cardiovascular system (I00-I99)
- Peripheral arterial occlusive disease (pAVD) – progressive narrowing or occlusion of the arteries supplying the arms/ (more commonly) legs, usually due to atherosclerosis (arteriosclerosis, hardening of the arteries).
- Thrombophlebitis (phlebitis)
- Deep vein thrombosis (TBVT) – formation of a blood clot with occlusion of a vessel.
Infectious and parasitic diseases (A00-B99).
- Leptospirosis (Weil’s disease) – infectious disease caused by leptospires.
Musculoskeletal system and connective tissue (M00-M99).
- Muscle enzyme disorder, unspecified
- Muscle hardening due to unaccustomed strain
- Muscle injury
- Muscular tension, unspecified
- Ruptured Baker cyst (popliteal: belonging to the popliteal fossa); popliteal cyst) – cysts usually become symptomatic only between the 20th and 40th year of life; however, they can also be observed already in the 1st decade of life; symptomatology: feeling of pressure in the area of the popliteal fossa with occasional radiation into the calf
- Transfer pain (Referred Pain):
- From the lumbar spine (LS): L4 + L5.
- From the knee (e.g. arthropathy/joint disease).
- Changes in the area of the knee joint
- Spinal changes, unspecified
Psyche – nervous system (F00-F99; G00-G99)
- Alcoholic polyneuropathy
- Motor neuron disease, unspecified (e.g., amyotrophic lateral sclerosis (ALS))
- Multiple sclerosis (MS)
- Polyneuropathy, unspecified (alcoholic or diabetic).
Symptoms and abnormal clinical and laboratory findings not elsewhere classified (R00-R99).
- Muscle cramps and spasms (e.g., simple calf cramps, unspecified).
Injuries, poisonings, and other sequelae of external causes (S00-T98).
- Muscle injuries, unspecified
- Ruptured (torn) Achilles tendon
Environmental stress – intoxications (poisoning).
- Lead poisoning
- Strychnine poisoning
Further
- Sports load
- Unaccustomed physical stress → muscle stiffness.