They are affections of muscles, tendons, nerves, articulations (cartilages, meniscuses) and bones. The most frequent affections are:

lumbagos

pain in the cervical region of the spìne

pains of the articulations

tendinitises

carpal tunnel syndrome

The parts of the body most frequently touched are: 

the spinal column

upper limbs (shoulder, elbow, wrist)

knees

STIFFNESS, LIMITATION OF THE MOVEMENTS AND ARTHROSIS

  With aging the connective tissue loss its elasticity and its constitution is changed in a worse structure.

According to Ladislas Robert, Research Director at the CNRS and Director of the Laboratory of biochemistry of the connective tissue from the Medicine Faculty of Paris-XII, the elementary fibers of collagen are linked by chemical bridges. The increase of the resistance of collagen with aging is the consequence of an increase of the quantity of  bridges or from an  alteration of their structure. This phenomenon is increased by the chemical affinity of glucose for the collagen tissue (1). The loss of male hormone lead to hyperglycemia as we have seen above. There is why the sweetened middle aged man becomes stiff.

At the same time the ground substance of the connective tissue is altered and the oxygenation of the connective cells is compromised. The rarefaction of the normal ground substance is the consequence of the loss of male hormones as demonstrated, in 1958, by Harry Sobel and Jessie Marmorston, from the University of Southern California in Los Angeles (2).

Those phenomenon added with overweight lead to arthrosis.

The detection of androgens' insufficiency is done by the study of the pool of androgens.

OSTEOARTICULAR DISEASES

In France, occupational doctors diagnosed an explosion of bone diseases between 1991 and 1994, with growth of 160 % compared to preceding years.

Back trouble, which is a major cause of disability, accounts for six million consultations a year, a third of rehabilitation prescriptions, 13 % of occupational accidents, 7% of work stoppages due to illness and 2,5% of non-hospital prescriptions. The deterioration of the muscular-bone-articular system is continually ignored.

Rheumatoid arthritis - Pool of androgens

In 2011, a Japanese study showed that dihydrotestosterone is a negative regulator of rheumatoid arthritis' pathogenesis by decreasing the inflammatory reactions.  pdf. (11).
The detection of androgens' insufficiency is done by the study of the pool of androgens.

OSTEOPOROSIS

 In 1978, Daniel Baran and his collaborators, from the department of Medicine and Pathology, Division of Bone and Mineral Metabolism from the Washington University School of Medicine, reported the positive effect of testosterone therapy on bone formation in a hypogonadic male with osteoporosis (3).

In 1981, Delmas and Meunier from the Research Laboratory on histodynamics of the bones and the Alexis Carrel Faculty of Lyon in France, reported eight cases of osteoporosis in eight men with low levels of male hormones (4).

In 1983, Gérard Milhaud from the University hospital Saint Antoine in Paris, has reported the fragility of the bones in climacteric women but also in climacteric man according studies on the mineral constitution of their bones (5). The rapidity of the mineral loss in man is slower than in women.

The same year, Doctor Foresta and his collaborators reported in the scientific revue Hormone Metabolic Research the linear relation between testosterone plasmatic levels and bones' density (6).

In 2000,   Vanderschueren and Vandenput from the Louvain University, Belgium,  confirmed the essential action of testosterone on bone growth (8) pdf. summary.

In 2004 and 2011, publications of searchers from the Louvain University, Belgium, confirmed again the essential action of testosterone on bone growth : 2004 (download summary) (download full text) (9) and 2011 (download full text) (10)

The detection of androgens' insufficiency is done by the study of the pool of androgens.

AMYOTROPHY

The metabolism of the muscle is influenced by testosterone which increases the quantity of specific contractile proteins as seen above. Testosterone increases also the input of glycogen into the muscle cells. Glycogen constitutes fuel or energy for the muscle's contraction. The link between glycogen and testosterone during exercise is reported by F. Plas from the University Hospital Pitié-Salpêtrière in Paris, in 1978 (7).

During the andropause disease the muscles are weak and exercise aggravates the loss of testosterone. In this situation any intensive sport is dangerous even the jogging. The heart which is also a muscle is deprived of its fuel and heart attacks and even sudden death may occur at any moment.

The detection of androgens' insufficiency is done by the study of the pool of androgens.

 Bibliography

11. Jian XU,Yuka ITOH, Hidetoshi HAYASHI, Takemasa TAKII, Keiji MIYAZAWA, and Kikuo ONOZAKI. Dihydrotestosterone Inhibits Interleukin-1a or Tumor Necrosis Factor a-Induced Proinflammatory Cytokine Production via Androgen Receptor-Dependent Inhibition of Nuclear Factor-k B Activation in Rheumatoid Fibroblast-Like Synovial Cell Line. Biol. Pharm. Bull. 34(11) 1724—1730 (2011)

10. Mieke Sinnesael, Steven Boonen,Frank Claessens, Evelien Gielen, and Dirk Vanderschueren. Testosterone and theMale Skeleton: A DualMode of Action : Journal of Osteoporosis. Volume 2011, Article ID 240328, 7 pages

9. Vanderschueren D, Vandenput L, Boonen S, Lindberg MK, Bouillon R, Ohlsson C. Androgens and bone : Endocr Rev. 2004 Jun;25(3):389-425.

8. Vanderschueren D, Vandenput L. Androgens and osteoporosis : Andrologia. 2000 May;32(3):125

1. ROBERT L. Les Horloges Biologiques. Nouvelle Bibliothèque Scientifique Flammarion, 1989.

2. SOBEL H. AND MARMORSTON J. Hormonal Influences Upon Connective Tissue Changes of Aging, in : PINCUS G (ed) Recent Progress in Hormone Research, vol 14. Academic  New York  1958.

3. BARAN D.T., M.A. BERGFELD,S.T. TEITELBAUM AND L.V. AVIOLI. Effect of testosterone therapy on bone formation in an osteoporotic hypogonadal male. Calcif. Tiss. Res. 2§ : 103-106, 1978.

4. DELMAS P. ET MEUNIER P.J. L'Ostéoporose au cours du Syndrome de Klinefelter.La Nouvelle Presse Médicale, 10 : 687-690, 1981.

5. MILHAUD G. Mécanisme d' Action de la Calcitonine au Niveau de la Matrice Calcifiable, in : L. Robert et H. Greiling Eds. Pharmacologie Cellulaire et Moléculaire des Maladies du Tissu

Conjonctif : 227-239. Boehringer. Ingelheim. Mannheim. Reims, 1983.

6. FORESTA C., BURNARDO B., RUZZA G. et al. Lower Calcitonin Levels in Young Hypogonadic Men with Osteoporosis :

 Horm. Metab. Res., 15 : 206, 1983.

7. PLAS F. -Variations de la Fonction Androgénique au cour des Efforts Prolongés : Bull. Acad. Nat. Méd., 162,6 : 494-499, 1978.