Rethinking the Use of Pelvic Binders with Acetabular Fractures
Pelvic binders can provide lifesaving compression in patients with hemodynamically unstable pelvic injuries. But a report in the March 11, 2015 JBJS Case Connector by Auston et al. emphasizes that such binders may do more harm than good in patients who have acetabular fractures without hemodynamic instability or other pelvic injuries. Because first responders or community physicians often apply pelvic binders, the authors cite the need for clearer guidelines for these devices and updated training of early clinical caregivers regarding their use. Potential complications of binder use cited previously in the literature include pressure sores, damage to internal organs, and sciatic nerve palsy, and Auston et al. suggest additional ones.
The authors describe three cases in which patients who were hemodynamically stable were placed in a pelvic binder, either during transport or ED evaluation, following blunt trauma sustained in motor-vehicle accidents. All three patients had acetabular fractures but no other abdominal or pelvic injuries. The authors suggest that pelvic binders may contribute to the displacement of acetabular fractures, and although they saw no visible evidence of chondral damage during open reduction and internal fixation of the fractures, they express concern about occult chondral abrasion and possible damage to chondrocytes at the cellular level if binders are used inappropriately.
The authors therefore conclude that while pelvic binders play an important role in patients with severe pelvic ring injuries and hemodynamic instability, “in the setting of a displaced acetabular fracture, we cannot recommend placement of a pelvic binder, even for pain relief or splinting during evaluation or transportation.”
JBJS Reviews Editor’s Choice–Bisphosphonate-Related Femoral Fractures
In December 1996, a group of investigators reported the results of the Fracture Intervention Trial, a randomized controlled trial that compared the effect of alendronate plus calcium or calcium supplementation alone on the risk of fractures in women who already had evidence of vertebral fractures. The results showed that in patients managed with alendronate, there was a 51% decrease in the risk of hip fractures, a 46% decrease in the risk of vertebral fractures, and a 44% decrease in the risk of distal radial fractures when compared with patients managed with calcium alone. These results, as well as those from several other reports, supported the regulatory approval of alendronate (marketed under the trade name Fosamax) for the treatment of postmenopausal osteoporosis in the United States and many countries abroad. Alendronate thus became the first drug in a class of compounds known as the nitrogen-containing bisphosphonates to demonstrate these beneficial effects.
Approximately a decade later, and after millions of patients had undergone treatment, some disturbing reports suggested a potential suppression of bone turnover in association with long-term alendronate therapy. Bone biopsies from selected patients suggested diminished kinetic indices of bone formation. This was believed to lead to increased susceptibility to fracture and delayed healing of nonspinal fractures such as fractures of the femoral shaft. Additional reports suggested the occurrence of insufficiency or low-energy fractures in patients who used alendronate for several years. While epidemiological findings suggested that these fractures are very rare even among women who have been managed with bisphosphonates for as long as a decade, the American Society for Bone and Mineral Research convened a task force to understand the pathophysiology of these atypical fractures and to gain further information on the association of these fractures with bisphosphonates. The term “atypical femoral fracture” was adopted to distinguish this type of fracture as a unique entity in order to avoid a suggestion that it is exclusively associated with bisphosphonate use.
Atypical femoral fractures can occur anywhere along the shaft of the femur from just distal to the lesser trochanter to just proximal to the supracondylar flare of the distal femoral metaphysis. They may be transverse or short-oblique in configuration, are typically noncomminuted or minimally comminuted, are associated with minimal or no trauma, and may be associated with a medial spike. Incomplete fractures may involve only the lateral cortex. Because these fractures occur as a result of brittle failure while most osteoporotic patients show some ductility with deformation prior to failure, atypical femoral fractures most likely occur through bone that has undergone alterations in its mechanical and material properties. This further supports the notion that these fractures are unique and distinct from typical osteoporotic fractures of the femur.
While current evidence suggests a strong relationship between the use of bisphosphonates and the genesis of atypical femoral fractures, we now know that denosumab, a drug that inhibits osteoclastogenesis but is unrelated to the bisphosphonates, also may be associated with these fractures. Moreover, some patients who have never taken bisphosphonates or denosumab have presented with what appear to be atypical femoral fractures. Thus, atypical femoral fractures are not exclusive to patients who use osteoclast-inhibiting drugs, and this presents a more complicated picture regarding the etiology of this unique type of fracture.
In the March 2015 issue of JBJS Reviews, Blood et al. summarize current thinking regarding the evaluation and treatment of atypical femoral fractures. The authors note that these fractures can be treated successfully with intramedullary nailing and discontinuation of bisphosphonate therapy. However, there is a potential for a delay in healing. Prodromal thigh pain and radiographic evidence of a radiolucent line in patients with a history of atypical femoral fracture or chronic bisphosphonate use are strong indicators of impending fracture. In these patients, prophylactic fixation should be considered. In addition, patients with prodromal thigh pain who are receiving chronic bisphosphonate therapy but do not have radiographic evidence of incomplete fracture require further workup and may benefit from magnetic resonance imaging. For patients who have incomplete fractures and no pain, the authors recommend a trial of conservative therapy, including protected weight-bearing, discontinuation of bisphosphonate therapy, and supplementation with calcium and vitamin D (800 to 1000 IU) per day. While no recommendation currently exists regarding the duration of bisphosphonate therapy, most experts recommend discontinuation after five years. Moreover, as bisphosphonates are not the only class of compounds that may be associated with these fractures, further information is needed in order to make informed decisions regarding the use of specific drugs and the duration of their use. While treatment of atypical femoral fractures with an anabolic therapy such as parathyroid hormone has been proposed, there are no definitive data to support this suggestion at this time.
The use of bisphosphonates and denosumab to treat osteoporosis represents a major step forward. However, it is possible that there are specific subsets of patients who are more sensitive to pharmacological suppression of bone remodeling and who may not be candidates for this kind of therapy. Further investigation is required to understand the safety of prolonged use of osteoclast-inhibiting drugs.
Thomas A. Einhorn, MD, Editor
Click here for another OrthoBuzz post about this JBJS Reviews article.
Cut Infection Risk: Give Antibiotics within 60 Minutes of Open Tibia Fractures
A level-II retrospective prognostic study of 137 patients with type III open tibia fractures found that those given antibiotics within 66 minutes of sustaining the injury were nearly four times less likely to develop a deep infection during a 90-day follow-up than those receiving antibiotics more than an hour after injury. This relatively short therapeutic window for antibiotic prophylaxis led study authors to conclude that “prehospital antibiotics may substantially improve outcomes for severe open fractures.” In an interview with Loyola Medicine, study co-author William Lack, MD encouraged further research into the safety and efficacy of allowing paramedics to administer antibiotics in such cases.
The study also found that patients whose wounds remained open beyond five days post-injury were more than seven times more likely to experience infections than those with earlier wound coverage, but the authors noted that time-to-wound-coverage is predominantly dependent on the condition of the wound.
Interstate Licensing Compact on Docket in 15 States
Since our last post about interstate physician licensing in August 2014, 15 states have introduced legislation to approve the plan, which would establish a voluntary process to streamline licensing for physicians in multiple states. Legislative chambers in three of those 15 states—South Dakota, Utah, and Wyoming—have already voted to endorse the compact. According to the Federation of State Medical Boards, the House chambers in Wyoming and Utah passed compact legislation unanimously.
It’s not surprising that largely rural states are leading the bandwagon of support for the compact, because one of its main objectives is to increase physician services in underserved areas via face-to-face visits with patients across nearby state borders or via telemedicine.
Message to Postmenopausal Women with Mild Knee OA: Jump!
A randomized study of 80 postmenopausal women with mild knee osteoarthritis found that those assigned to a supervised progressive-impact exercise program (including jumping and change-of-movement exercises) thrice weekly for a year experienced more biochemical improvements in their patellar cartilage, as determined by MRI T2 relaxation time, than those in a non-intervention control group. The exercise group also saw greater improvement in muscle strength and aerobic capacity, while patient-reported KOOS-score changes were similar in both groups.
Although many clinicians deem high-impact activity to be contraindicated in this population, this study suggests that postmenopausal women with mild knee OA can, under the supervision of a physical therapist, be encouraged to include high-impact exercises in their fitness regimen.
Preventing Atypical Femoral Fractures Related to Bisphosphonates
Physicians worldwide frequently prescribe bisphosphonates such as alendronate (Fosamax) and ibandronate (Boniva) to treat osteoporosis and prevent fragility fractures. Unfortunately, long-term bisphosphonate use has been linked to an increased risk of atypical femoral fractures. In the March 3, 2015 edition of JBJS Reviews, Blood et al. offer some guidance on how to prevent such fractures.
The authors note that prodromal thigh pain and a radiolucent line on X-rays of patients with a history of chronic bisphosphonate use are strong indicators of an impending fracture. Among bisphosphonate users who have an incomplete fracture with little or no pain, the authors recommend a trial of discontinued bisphosphonates, protected weight-bearing, calcium and vitamin-D supplementation, and possible teriparatide (Forteo) therapy. They add that prophylactic fixation should be considered if there is no radiographic or symptomatic improvement after two to three months of that conservative approach. Blood et al. further recommend that patients at high risk for atypical femoral fracture, should consider discontinuing bisphosphonate therapy after five years of continuous use. They also encourage orthopaedists to assess the contralateral femur for signs of impending fracture in patients who have already had an atypical femoral fracture.
The recommendations by Blood et al. notwithstanding, we should stress that the absolute risk of atypical femoral fractures fractures is low (3.2 to 50 cases per 100,000 person-years among short-term bisphosphonate users and about 100 cases per 100,000 person-years among long-term users). Consequently, for most people with osteoporosis, the proven fragility-fracture risk-reduction benefits of bisphosphonates outweigh the risks of atypical femoral fracture.
Readers interested in this subject may want to read a related Case Connections article, which springboards from a January 14, 2015 Case Connector article.
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