AFTER MID
SURGERY
DR. Ali Bakir
Orthopaedic
OSTEOPOROSIS
Dr. Ali Bakir
LECTURE8
OSTEOPOROSIS
Bone consists of a largely collagenous matrix (collagen type 1)which is impregnated with
mineral salts and populated by cells (osteoblasts and osteoclasts).
Definition
Osteoporosis is a generalized metabolic bone disease characterized by insufficient
formation or increased resorption of bone matrix that results in decreased bone mass.
Although there is a reduction in the amount of bone tissue, the tissue present is still
fully mineralized. In other words, the bone is quantitatively deficient but qualitatively
normal.
A combination which renders the bone unusually fragile and at greater than normal risk
of fracture in a person of that age, sex and race.
It should not be forgotten that osteoporosis is sometimes confined to a particular bone
or group of bones– Regional osteoporosis (for example due to disuse,immobilization or
inflammation) – which is usually reversible once the local cause is addressed
.
Generalized osteoporosis : may be physiological or feature of many systemic disorders.
POSTMENOPAUSAL OSTEOPOROSIS
Symptomatic postmenopausal osteoporosis is an exaggerated form of the physiological
bone depletion that normally accompanies ageing and loss of gonadal activity
RISK FACTORS FOR POSTMENOPAUSAL OSTEOPOROSIS
1-Caucasoid (white) or Asiatic ethnicity
2-Family history of osteoporosis
3-History of anorexia nervosa and/or amenorrhea
4-Low peak bone mass in the third decade
5-Early onset of menopause
6-Unusually slim or emaciated build
7-Oophorectomy
8-Early hysterectomy
9-Nutritional insufficiency
10-Chronic lack of exercise
11-Cigarette smoking
12-Alcohol abuse
INVOLUTIONAL OSTEOPOROSIS
Over the age of 75 patients (women and men) are more likely to be seen with fracture
of femoral neck. In advanced age the rate of bone loss slowly decreases but the
incidence of femoral neck and vertebral fractures rises steadily; by around 75 years of
age almost a third of white women will have at least one vertebral fracture. For reasons
that are not completely known age-related fractures are much less common in black
people.
POST-CLIMACTERIC OSTEOPOROSIS INMEN
With the gradual depletion in androgenic hormones,men eventually suffer the same
bone changes as postmenopausal women, only this occurs about 15 yearslater unless
there is some specific cause for testicularfailure. Osteoporotic fractures in men under 60
years ofage should arouse the suspicion of some underlying disorder notably
hypogonadism, metastatic bone disease,multiple myeloma, liver disease, renal
hypercalciuria,alcohol abuse, malabsorption disorder, malnutrition,glucocorticoid
medication or anti-gonadal hormonetreatment for prostate cancer.
Causes of secondary osteoporosis
1-Nutritional
Malabsorption
Malnutrition
Scurvy
2-Inflammatory disorders
Rheumatoid disease
Ankylosing spondylitis
Tuberculosis
3-Drug induced
Corticosteroids
Excessive alcohol
consumption
Anticonvulsants
Heparin
Immunosuppressives
4-Endocrine disorders
Gonadal insufficiency
Hyperparathyroidism
Thyrotoxicosis
Cushing’s disease
5-Malignant disease
Carcinomatosis
Multiple myeloma
Leukaemia
6-Other
Smoking
Chronic obstructive
pulmonary disease
Osteogenesis imperfecta
Chronic renal disease
Clinical features and diagnosis
#A woman at or near the menopause develops backpain and increased thoracic
Kyphosis; she, or someone in the family, may have noticed that her height has
diminished.
#Family History of osteoporosis.
#Body mass.
#Nutrition status poor.
#Alcohol, cigarette and chronic physical disease.
#History of fragility( low energy fractures): spine, wrist ,hip, proximal Humerus and
ankle.
X-rays and bone densitometry
The term osteopaenia is sometimes used to describebone which appears to be less
‘dense’ than normal on x-ray, without defining whether the loss of density is due to
osteoporosis or osteomalacia, or indeed whether it is sufficiently marked to be regarded
as at all pathological.
X-rays of the spine may show wedging or compression of one or more vertebral bodies
and often the lateral view also shows calcification of the aorta.
DEXA
The clinical and radiographic diagnosis should bebacked up by assessment of BMD as
measured by
DXA of the spine and hips, using the lower value ofthe two. In otherwise ‘normal’
women over the age of 50 years, anything more than 2 standard deviations below the
average for the relevant population group may be taken as indicative of osteoporosis.
BMD is strongly correlated with bone strength and is a predictor of fracture risk.
DXA may show significantly reduced bone densityin the vertebral bodies or femoral
neck.
The rate of bone turnover is either normal orslightly increased; measurement of
excreted collagen cross-link products and telopeptides may suggest ahigh-turnover type
of bone loss.
Once the clinical diagnosis has been established,screening tests should be performed to
rule out other causes of osteoporosis (e.g. hyperparathyroidism,malignant disease or
hypercortisonism).
Biochemical tests
# Ruling out other disorders.
# S.Ca , Ph , Alkaline phosphatase
25 hydroxy and 1-25 dihydroxy-vit D
PTH, thyroid function test, s. protein electrophoresis, ESR, Hb.
# The above tests are usually normal in postmenopausal, Involutional or post-climacteric
osteoporosis.
Prevention and treatment
Bone densitometry can be used to identify women whoare at more than usual risk of
suffering a fracture at themenopause, and prophylactic treatment of this group
issensible. However, routine DXA screening (even incountries where it is available) is still
not universally employed;for practical purposes, it is usually reserved forwomen with
multiple risk factors and particularly thosewith suspected estrogen deficiency
(premature or surgicallyinduced menopause) or some other bone-losingdisorder, and
those who have already suffered previouslow-energy fractures at the menopause.
Hormone replacement therapy (HRT)
Until the beginningof the twenty-first century HRT was the most widelyused medication
for postmenopausal osteoporosis.
Taking estrogen (or a combination of estrogen andprogesterone) for 5–10 years was
shown convincinglyto reduce the risk of osteoporotic fractures, thoughafter stopping
the medication the BMD gradually fallsto the usual low level. Moreover there was
growingconcern about the apparent increased risks ofthromboembolism, stroke, breast
cancer and uterinecancer. As more experience has been gained with otherantiresorptive
drugs, the preference for HRT haswaned.
Bisphosphonates
Bisphosphonates are now regarded asthe preferred medication for postmenopausal
osteoporosis. They act by reducing osteoclastic boneresorption and the general rate of
bone turnover. Thenewer preparations have been shown to prevent boneloss and to
reduce the risk of vertebral and hipfractures. Alendronate can be administered by
mouthin once-weekly doses for both prevention and
treatment of osteoporosis. Gastrointestinal side effects are a bother.
Parathyroid hormone
Trials of parathyroid hormone,either by itself or in combination with Alendronate,have
shown good results in obtaining a rise in BMD inpatients with postmenopausal
osteoporosis . This could be a way of managing patientswith severe osteoporosis who
do not respond tobisphosphonates alone.
Recent advances in drug treatment
A novel way ofreducing osteoclastic activity and bone resorption is to interrupt the
RANKL–RANK interaction which isessential for prompting osteoclastogenesis. Trials are
now being conducted using denosumab, an antibody to RANKL, which holds out the
promise of an effective new line of treatment for postmenopausal osteoporosis.
Management of fractures
Vertebral fractures are painful and patients will need analgesic treatment, partial rest
and assistance withpersonal care for about 6 weeks. Physiotherapy shouldinitially be
aimed at maintaining muscle tone andmovement in all unaffected areas; if pain is
adequatelycontrolled, patients should be encouraged to walk andwhen symptoms allow
they can be introduced to posturaltraining. Spinal orthosis may be needed for
supportand pain relief, but they cannot be expected tocorrect any structural deformity.
Operative measuresare occasionally called for to treat severe compressionfractures.
Balloon Kyphoplasty
Balloon kyphoplasty evolved as the next step in the treatment of vertebral compression
fractures. This is a minimally invasive procedure that involves reduction and fixation. The
procedure is performed through small instruments that are inserted into the vertebral
body through the pedicle. A small balloon is inflated to restore the height of a collapsed
vertebral body and create a cavity inside. The balloon is deflated and withdrawn, and the
remaining cavity is filled under low pressure with the surgeon's choice of material.
Essentially, this process stabilizes the vertebra internally and facilitates pain relief and
restores function rapidly. Restoring vertebral height and spinal alignment is believed to
be important in preventing long-term increased morbidity and mortality that arises from
vertebral compression fractures and spinal deformity.
Femoral neck and other long-bone fractures may need operative treatment.
Hemiarthroplasty using a cemented femoral prostheses or total hip replacement.
Intertrochanteric fractures – treatmentcompression screw and plate or blade plate.
Supracondylar fractures of femur - Dynamic condylar screw and plate.
Wrist fractures- Colles’ fracture– reduction and immobilization, early phsiotherapy.