Osteoporosis

Osteoporosis In Elderly

Osteoporosis is a chronic skeletal disease that causes reduced bone mass and deterioration of the bone microarchitecture, resulting in an increased risk of fracture.

Etiology :

In healthy subjects, bone remodeling is maintained by the strictely coupling activities of bone forming osteoblasts and bone resorbing osteoclasts.

 In elderly especially the females, estrogen deficiency increase bone turnover and osteoclast activity, resulting in imbalance between osteoclast and osteoclast leading to accelerated calcium loss, bone demineralization(loss of bone and decrease bone strength) that affect vertebrae, femoral neck, distal radius, and calcaneum.

Symptoms :

It is a silent disease becoming symptomatic only when fracture have occurred.

Patients may present with:

1. Bone pain: back pain is the most common complaint as vertebral bone mineral content decline more rapidly with aging.

2. Fractures: wedge fracture in thoracic spine, crush fracture in lumbar spine, hip fracture and colle's fracture.

3. Deformities of the vertebral coloumn: thoracic kyphosis which may be round when several vertebrae are affected.

4. Loss of height: compression fractures of vertebrae and kyphosis lead to loss of structures.

5. Loss of balance.

Diagnosis:

By Dual Energy X-ray Absorpiometery (DEXA).

Normal BMD: T- score between 2.5 and -1

Osteopenia (low BMD): T-score between -1 and -2.5

Osteoporosis : T- score lower than -2.5

Management of osteoporosis:

A.Exercise:

Aims:

1- To improve bone mass and morphology:

• Those with reduced level of activity : chair exercise, water exercise, stationary bicycle.
• Weight bearing exercises: include aerobics training such as walking (low-intensity weight bearing activity) and stair climbing/descending, brisk walking, walking with weighted vests, jumping and jogging (higher-intensity bone loading activities), resistance, endurance training.
• Resistive (strengthening exercise): the most effective strength training is high load low repetition (8 repetition, 3 sets).

Exercise prescription:

• Supervised strength training exercise training for 20-30 min., 2-3 times per week.
• Weight bearing exercises for 30-45 min., 3-4 times per week at 60% VO2 max.
• Supervised balance training and postural exercises.
• Instruction in safe movements

2-To relief back pain and reduce spinal deformity:

• Stretching exercises (pectoralis major, hip flexors)
• Thoracic and lumbar extension flexibility
• Strengthening exercises for abdominal muscles, neck, erector spinae and scapular muscles.
• Hyperextension should be avoided as it loads lumbar vertebral bodies.

3-Reducing risk of falls and fracture

• Resistive training 
• Balance training
• Hip and ankle strengthening 

Biological effect of exercise on bone

1. Increase muscle strength and BMD
2. Improve muscle control, balance, co-ordination
3. Reduce risk of fall and thus prevent fracture
4. Progressive high intensity resistive exercises improve physical function in elderly during weight bearing activities.
5. Exercise creates mechanical loading and strain on bone which influence the activity of osteoblast and osteoclasts, promoting osteoblasts proliferation in respond to this mechanical stimuliation, inhibiting osteoclasts differentiation 
6. Promote calcium absorption, utilization and deposition and so increase estradiol and testosterone levels.

Electrotherapy 

1- Pulsed electromagnetic field: frequency 50-150 Hz, low intensity, 30 min. 3 times per week for 3 months.

Application : on lumbar and hip regions

Biological effect: Influence bone metabolism by increasing calcium deposition in bone and improve osteoblast activity.

It has piezoelectric effect which increase calcium deposition in bone.

2- Pulsed ultrasound: frequency 1Mhz, intensity:0.5-w/cm2,  20 min., 5 times /week, for 4 weeks.

Application: over posterior aspect of L4 &L5.

Biological effect: it stimulates the synthesis of extracellular matrix proteins in cartilage, enhance chondrocyte maturation and endochondral bone formation.

Also, it accelerate osteogenesis due to its thermal effect which modulate cell membrane permeability.

3-Ultavilot B radiation: wave length 280 nm., 3 hours per day.

Application: perpendicular over patient only exposing thighs and leg.

Biological effect: help to transfer vit. D from inactive to active form which stimulates calcium deposition in bone.

c. Diet:

Balanced  diet:

Adequate intake of calcium, magnesium all important to proper bone metabolism. Vitamin D also to maintain bone mass.

d. Advices:

• Adequate calcium and vit. D  intake.
• Avoid cigarette and alcohol intake.
• Weight bearing exercise esp. ground reaction as jogging is recommended.
• Maintain healtyh life style and balanced diet.
• Safety measures at home such as avoid slippery rugs, stairs, low light environment, to reduce risk of fall and fractures.