1. Maher, Ann Butler

Article Content

Osteoporosis in Women With Disabilities

More than 26 million women with disabilities live in the United States. This article focuses on women with cognitive disabilities and women with physical disabilities that impair mobility; both groups are at high risk for osteoporosis.


Women With Physical Disabilities

Women with impaired mobility have many risk factors for osteoporosis including nonweight bearing, use of steroids or anticonvulsant medications, and lifestyles that offer less-than optimal sunlight exposure predisposing to Vitamin D deficiency.


Bone mineral density (BMD) in women after spinal cord injury is rapid with losses of 25 to 50% in the lower extremities in the first few years after injury. This rate then slows to age-matched controls. Women with spasticity have less bone loss than women with flaccid muscles.


Women with multiple sclerosis (MS) have significantly reduced bone mass, a high prevalence of vitamin D deficiency, and high fracture rates. Risk factors for these women include low bone density, poor mobility, frequent use of steroids and other immunosuppressant medications, and vitamin D deficiency. Short courses of steroids may not contribute to bone loss.


Inflammatory arthritides, such as rheumatoid arthritis and ankylosing spondylitis, have similar risk factors. In addition, women with rheumatoid arthritis have periarticular regional bone loss, which can lead to localized osteoporosis.


Women With Cognitive Disabilities

The American Association of Mental Retardation estimates that over 500,000 people with developmental disabilities are over 60 years old and this number is projected to double by 2030. The reason for the high prevalence of osteoporosis in this population is less clear.


Increasing use of anticonvulsant medications to manage behavior may be a factor. Anticonvulsant medication such as phenytoin, carbamazepine, and valproic acid can alter vitamin D metabolism. Phenytoin and carbamazepine are also direct toxins to osteoblasts.


Several studies have assessed the prevalence of osteoporosis and fracture rates in people with cognitive disabilities. Down syndrome seems to be an independent predictor of low bone mass with initial bone growth slow and much lower peak bone densities than normal, age-matched controls.


Practice Implications

Primary care providers need to be proactive in screening women with disabilities.


These women should be encouraged to eat a diet high in calcium and most should take calcium and vitamin D supplements. An exception to this may be women who are recovering from spinal cord injury. The massive bone loss may cause hypercalcemia and extra calcium supplementation may be inappropriate. Women who are ambulatory even partially should be encouraged to do weight-bearing activities.


Screening for BMD may be difficult in this population and there are no consensus guidelines currently available. Although central dual-energy X-ray absorptiometry (DEXA) scans are the gold standard, this may be infeasible because of positioning issues. Calcaneal ultrasound or DEXA may be the best choice in this group of women. Whether to screen at an earlier age is also a consideration.


Treatment Issues

Biphosphonates are effective for fracture prevention in women on steroids but there are no studies on the use of these medications in women on anticonvulsants. Biphosphonates also require an upright posture after administration, which may be difficult for some women with physical disabilities. Also, the risk of esophageal ulceration could be increased in individuals with oral motor dysfunction. Annual intravenous zoledronic acid may be a better treatment in the future.


Treatment for women who are paraplegic and who may have normal bone density in their upper extremities and osteoporosis in the lower extremities is unclear. Treatment decisions must be individualized.


Women on anticonvulsants may be candidates for early screening and aggressive preventive strategies. Every effort should be made to keep patients on only one anticonvulsant at a time. Although there are no outcome data to demonstrate effectiveness, it is recommended that women on anticonvulsants take calcium and vitamin D supplements.


Schrager, S. (2004). Osteoporosis in women with disabilities. Journal of Women's Health, 13(4), 431-437.


Loss of Consciousness: When to Perform Computed Tomography?

Minor head injury in children accounts for a large number of radiologic evaluations yearly in the United States. Most of these children do not suffer long-term neurologic sequelae. When should computed tomography (CT) scans be done?


This study prospectively evaluated clinical predictors of intracranial injury requiring neurosurgical evaluation in children with a Glascow Coma Score (GCS) with loss of consciousness/amnesia secondary to closed head trauma. The authors hypothesized that a standardized physical examination including GCS is predictive of intracranial injury as demonstrated on head CT scans.


Patients aged 2 to 16 years with minor closed head injury (GCS 13-15) and a history of brief loss of consciousness or amnesia (N = 98), was included in the study. Intracranial injury was 13.3%, consistent with the prevalence anticipated by the authors based on a retrospective review of hospital records. Positive CT scans were distributed among the GCS groups; findings included subdural hematoma, hemorrhagic contusion, subarachnoid hemorrhage, skull fracture, pneumocephalus, and mass effect.


The authors hypothesized that patients with a GCS of 15 and a completely normal examination including lack of a cephalohematoma would not have an intracranial injury and, thus, would not require CT scan. However, of the positive CT scans in this study, nine of these patients had a GCS of 15. The findings indicate a poor sensitivity and specificity of physical examination in predicting intracranial injury on CT scan. The authors state that clinical examination lacks diagnostic value in predicting CT scan findings and should not be used as a means of avoiding head CT in these patients.


Little research is available on the long-term outcome of children with mild closed head injuries regarding effects on learning, behavior, attention, and psychomotor skills. Minor injuries seen on CT scan may have neurologic sequelae; parents are advised to follow-up if their children begin experiencing problems in school or develop headaches.


Halley, M. K., Silva, P. D., Foley, J., & Rodarte, A. (2004). Loss of consciousness: When to perform computed tomography? Pediatric Critical Care Medicine, 5(3), 230-233.


Total Body Radiography for Trauma Screening

This article describes the authors' initial experience with the first digital total-body scanning system in the Northern hemisphere. First developed in South Africa for detecting theft by diamond miners, it required both low radiation exposure and speed so that large numbers of individuals could be scanned rapidly and frequently.


The original configuration was similar to a classic phone booth; individuals were scanned vertically. This was modified into a C-arm configuration that scans polytrauma patients through a 90[degrees] arc. The system, which is FDA approved, was delivered to the Maryland Shock Trauma Center in June 2003. As part of the product refinement process, a stretcher was developed to be part of the system, now called "Statscan." The stretcher can be used to transport the patient if needed.


The system is interfaced with a dedicated workstation as well as the radiology information system. Images can be loaded to CD or printed directly to film. The entire database of images can be retained in the system hard drive (36 GB disc) or can be permanently archived on DVD or transferred to a picture archiving and communication system network.


The patient-imaging table can accommodate a patient weighing up to 450 pounds and adjusts from 0 to 340 mm in height and 10[degrees] + Trendelenburg. Patient safety rails are carbon fiber and radiolucent so they can be left in place for imaging if needed. Preset protocols permit rapid setup.


At the Maryland Shock Trauma Center multiple views of most body parts can be obtained in under 5 minutes. Usual scans include a total-body anteriorposterior view, a lateral spine view, and a spine oblique projection. Higher resolution images can be obtained as needed. Radiation exposure is typically < 25% of the dose for a conventional radiograph of the same body part although it varies. Statscan is obtained after the patient has undergone a primary survey and vital signs are stable. Staff can remain close to the patient (within 4 feet) and the room requires no shielding.


The Statscan monitor can be placed next to the patient for immediate review of the images as well as to confirm placement of central lines, endotracheal tubes, and chest tubes. Findings can be used to guide computed tomography scans. The track of ballistic objects is easier to determine rapidly from the total-body digital radiograph.


Prospective studies underway are seeking to establish whether Statscan's image quality is comparable to, or better than, traditional methods; whether observed times savings actually produce faster diagnostic results; and whether more injuries are detected (especially orthopaedic injuries) requiring emergent or urgent treatment than are diagnosed with conventional approaches. The Statscan is now installed at three U.S. sites.


Miller, L. A., Mirvis, S. E., Harris, L., & Haan, J. (2004). Total-body digital radiography for trauma screening: Initial experience. Applied Radiology, 33(8), 8-14.


Why MRI Should Replace CT for Whole Body Scanning

Screening is systematic examination to detect unsuspected diseases. Methods include blood tests, urinalysis, and imaging studies. Surveillance refers to the search for disease in a healthy individual who is at risk for a particular disease. These differ from diagnostic studies, which are performed in an individual suspected of having a specific disease.


In theory, screening supports early detection and maximizes the chance of successful treatment and cure. A good screening test must have high sensitivity and high specificity to ensure that the test does not miss diseases that are present while minimizing the number of false-positive results. Safety and cost are also important factors. Magnetic resonance imaging (MRI) is approximately 20% more expensive than computed tomography (CT).


Because whole body screening with CT and magnetic resonance imaging (MRI) are relatively new and mostly on a private pay, self-referral basis, few comparison studies are available. Most existing information is from diagnostic studies. Overall, MRI is superior for examinations of the head, abdomen, and pelvis. CT remains superior for imaging of the lungs and for visualizing small arteries such as those within the heart. MRI is safer. There is no radiation, and the intravenous contrast agents cause less allergic reactions and have less association with kidney injury.


Why then, the author asks, is MRI still not considered the method of choice for whole body scanning? Historically, there are three reasons: MRI is much slower to perform than CT with lung imaging being suboptimal, the cost is higher, and CT is more available. Additionally, MRI studies are more difficult to perform and more complex to interpret.


Even with whole body scanning, we cannot assess for every disease. The author suggests that studies be tailored to types of disease most prevalent in the general population of a specific region and include the diseases a particular person is at risk of developing. In North America, the most prevalent diseases include stroke, heart attack, and cancer (primarily lung, colon, pancreas, lymphoma, liver, breast [in women], and prostate [in men]).


MRI currently can image the entire body with good quality and sensitivity to detect disease within a 15-minute period. Although optimal imaging of certain organs (e.g., heart, breast, colon) requires further development, current MR technology provides a diagnostically acceptable level of imaging.


Note: This author included no discussion about whether whole body screening should be done and, if so, under what circumstances.


Semelka, R. (2004). Why MRI should replace CT for whole body screening. Medscape Radiology, 5 (1). Retrieved June 23, 2004, from