Forearms aging

Hernandez-Avila, M., Colditz, G. A., Stampfer, M. J., Rosner, B., Speizer, F. E., Willett, W. C., Caffeine, moderate alcohol intake, and risk of fractures of the hip and forearm in middle-aged women, American Journal of Clinical Nutrition, 54, 157, 1991. 

Systemic administration of endothelin receptor antagonists or endothelin-converting enzyme inhibitors causes vasodilation and decreases arterial pressure in humans and experimental animals. Intra-arterial administration of the drugs also causes slow-onset forearm vasodilation in humans. These observations provide evidence that the endothelin system participates in the regulation of vascular tone, even under resting conditions. The activity of the system is higher in males than in females. It increases with age, an effect that can be counteracted by regular aerobic exercise. 

FIGURE 32.6 Age related comparisons of friction and electrical impedance. No significant differences were apparent between old and young skin on the volar forearm. Within each category, the proximal right arm friction and electrical impedance measurements were different from the distal right arm (P <. 001). Reproduced from Sivamani et al24... 

Eisner, P., Wilhelm, D., and Maibach, H.I., Frictional properties of human forearm and vulvar skin influence of age and correlation with transepidermal water loss and capacitance, Dermatologica, 1990 181 88-91. 

The site and type of bone deformity seen in rickets depend on the age of the child. In a small infant, deformities of the forearms and anterior bowing of the distal tibias are more common. Clinical features such as craniotabes (areas of thinning and softening in the bones of the skull), hypotonia, and tetany are common in vitamin D-deficiency rickets, which occurs more frequently in infants 1 year old or younger. These features may be absent in calcium-deficiency rickets, which usually presents after the age of 1 year or after the child has been... 

Andrawis NS, Jones DS, Abernethy DR. Aging is associated with endothelial dysfunction in the human forearm vasculature. J Am Geriatr Soc 2000 48 193-8. 

In adults receiving long-term parenteral nutrition, despite its anabolic effects on other tissues, there is no improvement in bone density. Infants treated with parenteral nutrition from birth also develop low bone density for age, suggesting that parenteral nutrition treatment in some way contributes to the osteopenia (5). A 17% long-term increase in spinal bone mineral content has been shown in patients who have received parenteral nutrition solntions without vitamin D. However, this rise was nearly balanced by a 15% fall in hip bone mineral content (115). In a Danish study of bone mineral content in adults receiving home parenteral nutrition for short bowel syndrome, despite the fact that all were on free oral intake as a supplement to the parenteral nutrition, 47% had mandibular osteoporosis while 33% had osteoporosis in the forearm and radiographic changes of osteoporotic fractures in the vertebral column. Dental and periodontal tissues were normal (116). 

Nicolau syndrome (embolia cutis medicamentosa) is a very rare complication of intramuscular injections, in which there is extensive necrosis of the injected skin area, perhaps due to accidental intra-arterial and/or para-arterial injection (233). It usually occurs in children in a review of 102 patients, 80 were under 12 years of age (234). Complications can include everything from an ischemic syndrome with local necrosis of the skin, subcutaneous tissue, and muscle, often combined with vascular and nervous system involvement, intestinal and renal hemorrhage, necrosis of the entire leg, and even paraplegia from spinal cord damage (235-241). Necrosis of the forearm has been described in two patients after inadvertent intra-arterial administration of dicloxacillin (242). 

Osteoporosis is the most prevalent metabolic bone disease in the United States and results in 1.5 million fractures each year. Osteoporosis is associated with an increased risk for vertebral, hip, and distal forearm fractures. At age 50, women have a lifetime fracture risk (any of the above three sites) of about 40%. Men have a lifetime fracture risk of approximately one third that of women. Since trabecular bone turns over at five to seven times the rate of cortical bone, fractures of bones that are predominantly trabecular (vertebra and distal forearm) occur earlier in life. One third of women older than 65 years suffer vertebral crush fractures. Vertebral crush fractures can occur acutely and result in disabling pain and discomfort. Long-term complications include immobility and loss of height. Secondary problems include protuberant abdomen, chronic constipation, and loss of self-esteem. Fractures of bone with more cortical bone (proximal femur or hip) occur later in life. For women, the lifetime risk of hip fracture is 15%. The mortality rate accompanying hip fracture may be as high as 20%. Twenty-five percent of the survivors are confined to long-term care... 

Clinically, osteoporosis is categorized as postmenopausal, age-related, or secondary. Postmenopausal osteoporosis affects primarily trabecular bone in the decade following menopause, with fractures occurring predominantly at vertebral and distal forearm sites. Within a few years after peak BMD is attained, usually in the mid- to late-30s, bone loss slowly begins. The cumulative effect over time can translate into age-related osteoporosis that affects both cortical and trabecular bone and leads to vertebral, hip, and wrist fractures. Secondary osteoporosis is caused by either diseases or medications and afflicts both bone types. Secondary causes can be found in 11% to 31% of women and 30% to 54% of men. ... 

A sufficient number of overtly healthy subjects over the age of 18, but under the age of 70, should be recruited into the study to ensure that at least 18 subjects per product evaluated complete the study. A reference product should be included in the study design to assure the internal validity of the study—i.e., that the reference product provides the same efficacy in this study as it has demonstrated in the past [9], Insofar as possible, to ensure an unbiased sampling, subject groups should be of mixed sex, age, and race. All subjects hands must be free of clinically evident dermatoses, injuries to the hands or forearms, open wounds, hangnails, and/or any other disorders that may pose a health threat to the subject. Standard institutional review board (IRB) procedures and protoeols should be in place and used throughout this evaluation. ... 

Joshua sucked in a breath. Now what "You got me." He was telling it to a gleaming brass breastplate, one with distinctly feminine contours. It belonged to a cosmonik that resembled some steam-age concept of a robot solid metal bodywork and rubbery flexible joints. Definitely a cosmonik, Joshua determined after a quick survey, not combat boosted, there was too much finesse in the ancillary systems braceleting each of the forearms. This was a worker, not a warrior. 

This paper describes an indentation experiment to investigate in vivo the bulk mechanical properties of the composite of skin and underlying tissues on the anterior aspects of human forearms and thighs by applying constant pressures. Significant variations in tissue stiffness with sex, age and body site were also demonstrated. 

Fractures account for 10%-25% of all injuries in children. Boys are affected more conunonly than girls. From birth until the age of 16 years of age, a girl has a 27% chance of sustaining a fracture vdiile this rises to 42% for boys (Landin 1997). The physis is the weakest part of the bone and diaphyseal long bone fractures account for approximately 10% of children s fractures. Of these, the tibial shaft is most conunon, followed by diaphyseal fractures of the forearm... 

Monteggia injuries occur most frequently between the ages of 5 and 7. Patients will generally complain of forearm and elbow pain. If the ulna is fractured, pain will be maximal in the arm and there may be swelling and deformity. The elbow will also be swollen. In 10%-20% of cases, a neuropraxia of the radial nerve will be present, particularly if the radial head is dislocated laterally or anteriorly. Most of these nerve injuries will recover within 6-9 weeks and intervention is not indicated unless there is no sign of clinical or electromyographic recovery at 6 months. 

Avulsion fractures of the medial epicondyle are seen between the ages of 9 and 15, after the apophysis becomes a separate ossification nucleus from the epiphysis of the distal humerus and before it fuses with the distal humerus. The medial epicondyle is a traction apophysis for the flexor group of forearm muscles, and also serves as an attachment for the ulnar collateral ligaments and the joint capsule. This injury accounts for up to 10% of elbow fractures. 

The most common pattern of cutting-fluid dermatitis is that of a patchy eczema involving the backs of the hands, the forearms, the backs and sides of fingers and web spaces. The appearance may be confused with constitutional discoid eczema, particularly in middle-aged men. Although patchy patterns are most common, other patterns of eczema may also be found, including fine follicular eczema, continuous confluent areas and dry, scaly finger webs. 

Fig. 5. Allergic contact dermatitis to a rubber glove. A middle-aged woman presented with dyshidrotic eczema of the fingers and was advised to wear rubber gloves for household work. Several months later, she developed this erythematous, scaling dermatitis of the dorsal hands. Note the demarcation at the wrists with patches of dermatitis about the mid-forearm. Patch testing revealed allergic reactions to both thiuram and carba mixes. Her dermatitis cleared with the use of cotton liners and vinyl gloves. Reproduced with the permission of the Ronald 0. Perelman Department of Dermatology, New York University School of Medicine, New York, NY...

Examination showed a healthy middle-aged man who was trim and fit. He was in good health other than the pain in the elbow. The lateral epicondyle was tender to palpation, as were the muscles of the lateral forearm. His grip was weaker on the right than the left, and supination against resistance was painful. 

Vignette 19. Carpal-tunnel median-nerve, and forearm ulnar-nerve, pressure neuropathies somewhat common in aged persons and often very treatable... 

Carry MR, Horan SB, Reed SM et al. (1993) Structure, innervation, and age-associated changes of mouse forearm muscles. Anat Ree 237(3), 345-357. 

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