Own the Bone: Osteoporosis and the Orthopaedic Surgeron

As orthopaedic surgeons, we see a lot of patients who have fragility or osteoporosis related fractures.  These fractures are defined as those that occur from a standing height and are pathologic fractures.  Common fragility fractures include vertebral body compression fractures, femoral neck fractures, and distal radius fractures.  It has been estimated that 1.5million osteoporosis related fractures occur annually, to the tune of approximately $10 billion.  Hip fractures in osteoporotic individuals increases the risk of death in the next year by 10-30%.  Individuals who present with one fragility fracture are at increased risk of suffering from another fracture in the future.  In fact, this and age are the two most important non-modifiable risk factors for osteoporosis related fracture.

Osteoporosis is the result of an imbalance in bone metabolism.  In the physiologic system, bone is constantly being broken down and repaired by a very tightly controlled interplay between osteoblasts (bone forming cells) and osteoclasts (bone resorbing cells).  This interplay is modulated by a variety of hormones including parathyroid hormone, calcitonin, Vitamin D, estrogen and testosterone, just to name the most important.

There are two types of osteoporosis:  primary and secondary osteoporosis.  Primary osteoporosis is the most common and is related to menopause (or loss of estrogen) or extremes of age (also known as senile osteoporosis).  Secondary osteoporosis  is the result of a disease process such as multiple myeloma or endocrine imbalance.  Secondary osteoporosis can also be caused by exogenous corticosteroid use, even at doses as low as 10mg daily, although some may not argue this is not a necessarily low dose of prednisone.

Because of the morbidity and mortality of osteoporosis related fractures, not to mention the cost of care, appropriate individuals should be screened for the diagnosis of osteoporosis.  This includes all women over 60 years of age, men over seventy, and individuals over 50 at increased risk for osteoporosis:  those with previous fragility fracture, family history of fractures, frailty, low BMI, and treatment with medications such as corticosteroids, anticonvulsants, long-term heparin use, chemotherapeutic/transplant drugs, hormone/endocrine therapies, lithium and aromatase inhibitors.  Of course, all individuals presenting with suspected fragility fractures should also be screened for osteoporosis, either in the acute setting or as an outpatient soon after their discharge from the hospital.

Screening is achieved through a variety of modalities, most common being dual energy x-ray absorptiometry (DXA).  This radiographic test is used to asses bone density in the hip and spine.  This density is then assigned a t-score and a z-score.  The t-score is a comparison to the bone density of healthy young adults.  The z-score is a comparison to age and sex matched individuals.   Most commonly, the t-score is used to make a diagnosis of osteoporosis.  A t-score greater than -2.5 standard deviations (SD) from the mean is considered to be significant enough to make the diagnosis of osteoporosis.  T-scores from -2.5 to -1.5 SD are considered to be diagnostic for osteopenia.

Individuals who present with fragility fractures should have a laboratory work-up to rule out secondary causes of osteoporosis.  These studies include CBC with differential, complete metabolic profile including alkaline phosphatase, TSH, and Vitamin D levels.  Other studies to consider include serum protein electrophoresis (SPEP), 24-hour urinary calcium, parathyroid hormone, testosterone (in males), and many others.

In addition to treatment of the fracture, individuals found to have osteoporosis should be undergo treatment to prevent further bone loss and, in the ideal world, promote a more physiologic bone remodeling to occur.  Those who smoke or drink alcohol excessively should be counseled to stop.  Post-menopausal women should receive between 1200-1500mg of calcium daily.  Adults greater than 50 years of age should receive 800-1000 IU of vitamin D3 daily.  Individuals with osteoporosis should be encouraged to exercise and should undergo evaluation for fall risk.  This often includes a visit to the home and scrutiny of medication lists for medications which may increase risk of fall.  Lastly, medications intended to alter the course of the disease process such as bisphosphanates and estrogen therapy, among other, should be prescribed.  This will often entail consultation with a primary care physician or endocrinologist.

As i mentioned in the title of this post, the American Orthopaedic Association has started a campaign that they call Own the Bone.  This initiative was designed to increase awareness and encourage orthopaedic surgeons to take a more active role in the prevention, diagnosis and treatment of osteoporosis.  Of course, the management of osteoporosis requires a multi-disciplinary approach, but the catalyst, unfortunately, for treatment is often the first diagnosis of a fragility fracture.   One observational study published in The Journal of Bone and Joint Surgery (JBJS)  by Dell et al. outlined a process by which a group in the Kaiser system was able to decrease their incidence of hip fractures by 38% (970 fractures) using a multi-disciplinary screening approach.  If the cost of treating one fracture is estimated at $30,000, that amounts to a total savings of over $29million.

Next time you see a patient with a hip fracture, think beyond three screws versus intrameduallary nail.  Start the process to rule out osteoporosis.  Consult medicine colleagues to assist in the diagnosis and management of the disease.  When seeing patients in the office for non-fracture care, identify and encourage screening in appropriate individuals.  This is a way we can have a significant impact on the life expectancy and quality of life of our patients.

Sources


Dell et al.  "Osteoporosis Disease Management:  What Every Orthopaedic Surgeon Should Know."  JBJS.    
     2009;91  Suppl 6:79-86.
Jacobs-Kosman et al.  "Osteoporosis."  Emedicine:  Rheumatology.  
     http://emedicine.medscape.com/article/330598-overview 
Lucas and Einhorn.  "Osteoporosis:  The Role of the Orthopaedist."  JAAOS.  1993;1:48-56.