Osteoporotic Ankle Fractures




Ankle fractures are one of the most common injuries in the elderly and their incidence is anticipated to increase over the next 20 years. Appropriate management of ankle fractures in this population requires an understanding of the issues unique to the elderly. Osteoporosis must be considered when counseling patients about their ankle fracture. Good outcomes can be achieved with surgical fixation of ankle fractures in the elderly. Postoperative complications are higher in patients with diabetes and peripheral vascular disease, and in patients who smoke. This article reviews how to evaluate and treat ankle fractures in elderly patients with osteoporosis, evaluates the outcomes, and discusses surgical techniques.


Key points








  • Osteoporotic ankle fractures commonly occur in the elderly and are anticipated to increase in incidence over the next 20 years.



  • Ankle fractures differ from vertebral and hip fractures in the elderly and are associated with different risk factors.



  • The initial assessment of elderly patients with ankle fractures should be thorough and must take into consideration ambulatory status; comorbidities, such as diabetes mellitus; dementia; and bone health.



  • Good surgical outcomes are obtained in elderly patients with unstable ankle fractures. Diabetes, peripheral vascular disease, smoking, and dementia have been associated with increased postsurgical complications.



  • Several different surgical techniques have been described to achieve stable fixation in patients with osteoporotic ankle fractures with good results.






Introduction: defining the problem


Ankle fractures in the elderly pose a significant burden on society and health care in the United States. Also referred to as low-energy trauma, age-related, or fragility fractures in the literature, ankle fractures are one of the most common fractures in the elderly and its incidence will likely increase over the next 20 years in developed nations. Moreover, although their true economic impact is unknown, healthcare costs for osteoporotic ankle fractures is estimated to increase over the next decade as is projected for other fragility fractures.


A concept that has emerged in epidemiologic studies, and at first glance seems counterintuitive, is that osteoporosis is not a risk factor for ankle fractures. In 2003, Hasselman and colleagues followed more than 9000 elderly white women for a 10-year period and documented 291 ankle fractures. Risk factors for ankle fractures in this cohort included younger age (71 vs 71.7); higher body mass index (27.6 vs 26.5); and a prior fall within 12 months. Peripheral bone mass was not found to be a risk factor. Other large epidemiologic studies have demonstrated similar findings and many have theorized that obese elderly individuals at high risk for falls are at greater risk for ankle fractures than those with osteoporosis. A comprehensive list of factors associated with elderly ankle fracture is shown in Box 1 . In a more recent study, Pritchard and colleagues followed a cohort of more than 3000 women older than age 50 for 5 years to assess the relationship between prior ankle fractures and a major osteoporotic fracture event (ie, hip or vertebral fractures). Ankle fractures did not predict future fragility fractures, but were associated with obesity and a history of prior fractures. Indeed, ankle fractures in the elderly are associated with risk factors that are different from osteoporotic hip and vertebral fractures.



Box 1





  • Risk Factors



  • Smoking



  • Obesity



  • Vigorous physical activities



  • Sedentary individuals



  • Polypharmacy



  • Diabetes



  • Previous falls



  • Fracture history



  • Low bone mineral density at distal radius



  • Younger age



  • Female gender




  • Protective Factors



  • Vitamin D supplementation



  • Estrogen supplementation



  • Decreased weight gain



Patient factors associated with ankle fractures in the elderly


Although osteoporosis is not a risk factor for ankle fractures, it is a risk factor for the failure of surgical fixation in ankle fractures. Difficulties with the fixation of osteoporotic ankle fractures are best highlighted by the varying opinions and surgical techniques in the orthopedic literature. Although some outcome studies suggest nonoperative management because of high surgical complications rates and failure of fixation, others suggest improved radiographic and clinical outcomes with surgical fixation. Opinions on the subject even vary with geographic location of the authors. Physicians on the west coast are more apt to surgically treat ankle fractures, whereas physicians on the east coast or with nearby teaching institutions are less apt to operate. Surgical techniques range from standard plating with various methods of augmentation to locked plating technology to intramedullary nails to ankle fusions.


This article reviews the unique features of treating osteoporotic ankle fractures. It explores how to choose the best treatment plan based on the initial evaluation of the patient and anticipated outcomes. The difficulties of maintaining surgical fixation in osteoporotic ankle fracture are discussed and ways to augment fixation are shared. Finally, postoperative issues, such as time considerations for protected weight bearing and rehabilitation, are considered.




Introduction: defining the problem


Ankle fractures in the elderly pose a significant burden on society and health care in the United States. Also referred to as low-energy trauma, age-related, or fragility fractures in the literature, ankle fractures are one of the most common fractures in the elderly and its incidence will likely increase over the next 20 years in developed nations. Moreover, although their true economic impact is unknown, healthcare costs for osteoporotic ankle fractures is estimated to increase over the next decade as is projected for other fragility fractures.


A concept that has emerged in epidemiologic studies, and at first glance seems counterintuitive, is that osteoporosis is not a risk factor for ankle fractures. In 2003, Hasselman and colleagues followed more than 9000 elderly white women for a 10-year period and documented 291 ankle fractures. Risk factors for ankle fractures in this cohort included younger age (71 vs 71.7); higher body mass index (27.6 vs 26.5); and a prior fall within 12 months. Peripheral bone mass was not found to be a risk factor. Other large epidemiologic studies have demonstrated similar findings and many have theorized that obese elderly individuals at high risk for falls are at greater risk for ankle fractures than those with osteoporosis. A comprehensive list of factors associated with elderly ankle fracture is shown in Box 1 . In a more recent study, Pritchard and colleagues followed a cohort of more than 3000 women older than age 50 for 5 years to assess the relationship between prior ankle fractures and a major osteoporotic fracture event (ie, hip or vertebral fractures). Ankle fractures did not predict future fragility fractures, but were associated with obesity and a history of prior fractures. Indeed, ankle fractures in the elderly are associated with risk factors that are different from osteoporotic hip and vertebral fractures.



Box 1





  • Risk Factors



  • Smoking



  • Obesity



  • Vigorous physical activities



  • Sedentary individuals



  • Polypharmacy



  • Diabetes



  • Previous falls



  • Fracture history



  • Low bone mineral density at distal radius



  • Younger age



  • Female gender




  • Protective Factors



  • Vitamin D supplementation



  • Estrogen supplementation



  • Decreased weight gain



Patient factors associated with ankle fractures in the elderly


Although osteoporosis is not a risk factor for ankle fractures, it is a risk factor for the failure of surgical fixation in ankle fractures. Difficulties with the fixation of osteoporotic ankle fractures are best highlighted by the varying opinions and surgical techniques in the orthopedic literature. Although some outcome studies suggest nonoperative management because of high surgical complications rates and failure of fixation, others suggest improved radiographic and clinical outcomes with surgical fixation. Opinions on the subject even vary with geographic location of the authors. Physicians on the west coast are more apt to surgically treat ankle fractures, whereas physicians on the east coast or with nearby teaching institutions are less apt to operate. Surgical techniques range from standard plating with various methods of augmentation to locked plating technology to intramedullary nails to ankle fusions.


This article reviews the unique features of treating osteoporotic ankle fractures. It explores how to choose the best treatment plan based on the initial evaluation of the patient and anticipated outcomes. The difficulties of maintaining surgical fixation in osteoporotic ankle fracture are discussed and ways to augment fixation are shared. Finally, postoperative issues, such as time considerations for protected weight bearing and rehabilitation, are considered.




Initial evaluation


Elderly patients, with or without ankle fractures, tend to be osteoporotic. These patients’ circumstances are complicated by several factors that must be identified in the initial assessment by the surgeon to develop a good treatment plan. Patient factors that must be identified include preinjury functional limitations, systemic medical problems, risk factors for fragility fractures, polypharmacy, cognitive changes, and end-of-life issues. Obtaining an accurate history is a time-consuming process that always requires a thorough review of medical records and often requires the assistance of family members, healthcare proxies, and healthcare aides. In patients with dementia and a poor support network, the physician may have to rely solely on medical records, which may be incomplete. Medical consultation with an internist or geriatrician is an invaluable tool in the assessment process and is essential for managing the various medical issues unique to the elderly. At our institution, a protocol that involves early medical consultation within the emergency department for patients with geriatric hip fractures has proved to be effective and serves as a model for the management of trauma in the elderly. Consultation with geriatricians in the management of nonhip fragility fractures is not automatically obtained at our institution, and there is currently no literature to suggest its effectiveness. Nonetheless, the success of our geriatric hip program has set the standard of care for geriatric trauma, and medical consultation is frequently sought in the management of elderly ankle fractures.


The second task when evaluating ankle fractures in the elderly is characterizing the injury itself. Some of these characteristics can be elucidated in the patient’s history and include the mechanism and timing of injury, ability to ambulate after the injury, and history of osteoporosis. Other injury characteristics that the surgeon must know are determined by the physical examination. It is imperative to inspect the ankle for the quality of the soft tissue envelope and the presence of ulcers, blisters, or an open fracture. Light palpation of the foot, leg, and knee are important, as is a complete neurovascular examination. Testing with a 5.07 (10 g) Semmes Weinstein monofilament should be considered in patients suspected of peripheral neuropathy, and is imperative in all patients with diabetes. Peripheral vascular disease is not uncommon in the elderly and noninvasive vascular studies should be obtained in patients with diminished or absent pedal pulses, and in patients with ulcers or skin changes concerning for peripheral arterial disease. Vascular surgery consultation is recommended in patients with abnormal noninvasive vascular studies at our institution. The last component to a good examination is assessing the patient from head to toe to identify other associated injuries. Special attention should be paid to the head, proximal humerus, distal radius, and hip because these are frequently injured during ground level falls.


Standard imaging should be obtained in all patients with ankle trauma and includes anteroposterior, mortise, and lateral views of the ankle, and radiographs of the foot and tibia. Advanced imaging, such as a computed tomography scan, is rarely needed, but may be helpful in assessing the size of a posterior malleolus fragment or assessing the joint if there is suspicion for intra-articular involvement. Stress or weight-bearing views can help distinguish between stable and unstable ankle injuries and can further guide treatment decisions.


Most ankle fractures sustained in the elderly are lateral malleolus fractures. There seems, however, to be a higher rate of complex ankle fractures in elderly patients compared with younger patients. In a retrospective comparison of patients that underwent surgical fixation of unstable ankle fractures, a higher occurrence of bimalleolar and trimalleolar fractures was observed in patients older than age 65 years versus patients younger than age 65 years.


Any elderly patient being considered for surgery requires preoperative laboratory tests including a hematocrit, basic blood chemistries, and coagulation studies. In addition to these routine assessments, hemoglobin A 1c levels must be checked in all patients with diabetes to evaluate their overall glycemic control and predict their capacity to heal wounds. Nutritional laboratory studies, such as serum albumin or total lymphocyte count, have been correlated with wound healing and may be helpful in patients with diabetes or who are malnourished.


All elderly patients that sustain an ankle fracture require an evaluation of their overall bone health. Patients should be screened for a history of fragility fractures, prior bone mineral density scans, and prior use of medications for osteoporosis. Metabolic bone laboratory studies are recommended and include serum calcium, 25-hydroxyvitamin D, parathyroid hormone, and thyroid-stimulating hormone levels. Patients should be counseled about safe exercise and calcium and vitamin D supplementation, and encouraged to participate in fall-reduction programs. It is imperative for orthopedic surgeons to play an active role in the diagnosis and education of osteoporosis, and refer untreated or undertreated patients at high risk for fragility fractures to their primary care physicians or metabolic bone clinics for appropriate treatment. The patient’s past medical history, presentation, current medications, and past response to surgery, such as a prior nonunion, can prompt the treating orthopedist to obtain a more detailed medical work-up for osteoporosis. Several programs, such as “Own the Bone,” have been developed to help orthopedists identify and manage patients at high risk for future fragility fractures. Dell and colleagues provide an excellent summary of osteoporosis, and spell out realistic goals for all orthopedists to accomplish in their practice. Fig. 1 is a simple flowchart demonstrating how we typically evaluate patients suspected to have osteoporosis.




Fig. 1


A flowchart demonstrating how the authors typically evaluate patients suspected to have osteoporosis. BMD, bone mineral density; DEXA, dual-energy X-ray absorptiometry; GI, gastrointestinal; OI, osteogenesis imperfecta; SPEP, serum protein electrophoresis; TSH, thyroid-stimulating hormone.

( From Patel A, Puzas E, Baumhauer J. Practical osteoporosis management: topical review. Foot Ankle Int 2010;31(4):354–60; with permission.)


After the circumstances of the patient and characteristics of the injury have been fully assessed, the physician and patient (or patient’s family) must make an informed decision between nonoperative or operative treatment plans. A dialogue with the patient and often the patient’s family is beneficial and necessary to fully elicit a patient’s wishes and address and answer all potential concerns or questions. The role of involving the patient’s family or healthcare proxies becomes particularly more relevant in patients with cognitive dysfunction, codependence on family members for activities of daily living, or patients dealing with end-of-life issues. This is often a complex process, and should be guided by the surgeon’s experience and knowledge of literature regarding outcomes in ankle fractures of the elderly.




Outcomes


In the past, many viewed operative fixation of ankle fractures in the elderly as imprudent secondary to the high rate of complications and marginal clinical outcomes reported in the literature. Beauchamp and colleagues and Litchfield retrospectively reviewed patients older than age 50 and 65 years, respectively, with unstable ankle fractures. Both studies reported high rates of deep infection (>11%) and malunion (>14%) in the operative group. Litchfield reported only 58% of patients to have satisfactory results with surgery, and emphasized that patients with osteoporotic bone were likely to have poor clinical results. Beauchamp and colleagues further questioned the role of surgery for ankle fractures in the elderly because the clinical outcomes between the operative and nonoperative groups were similar at 2 years. Both studies failed to report on systemic illnesses; lacked validated outcome measures; and have been criticized for early, unprotected weight bearing as soon as 4 weeks following the operative procedure.


In a more recent prospective study by Salai and colleagues, patients older than age 65 years with trimalleolar ankle fractures were randomized to treatment by either cast immobilization or internal fixation followed by cast immobilization for 6 weeks after initial stable reduction was achieved in the operating room by a senior orthopedic resident. At an average follow-up time of 37 months, the nonoperative group had a significantly better American Orthopedic Foot and Ankle Society score than the surgically treated group. Approximately 32% patients within the operative group required additional surgery for the removal of symptomatic hardware. The authors conclude that nonoperative treatment can provide superior clinical outcomes than surgery. This study failed to address systemic illnesses and 61% of patients within the operative group (30 of 49 patients) were surgically treated because of the inability to achieve an acceptable initial stable reduction in the operating room, thus leaving only 16 patients in the nonoperative group. Theoretically, the patients in the nonoperative group represented a more inherently stable fracture pattern than those patients treated surgically, and could represent a potential confounder in their final analysis between the groups.


The high complication rates and poor clinical outcomes associated with ankle fractures in an elderly population with osteoporosis are likely overstated in these studies. All three studies failed to account for the influence of systemic illnesses on complications rates; and all three studies used nonvalidated patient outcome measures. Moreover, the preponderance of literature suggests lower complication rates and better clinical outcomes than what is stated in these studies.


In a review of more than 33,000 patients from the Medicare national registry from 1998 to 2001 with an ankle fracture between the ages of 65 and 99 years, Koval and colleagues reported an overall complication rate of 2% at 2 years in the operative group. The most common complication was hardware irritation (11%), and the most common reoperation was for removal of hardware (11%) over the course of 2 years. Rates of revision of internal fixation or other salvage procedures were less than 1%. Peripheral vascular disease, diabetes, and a Charlson index of one or more were predictive of a higher complication rate at 1 month and 1 year. Increasing age (per decade), peripheral vascular disease, diabetes, and a Charlson index of one or more were predictive of higher mortality rates at 1 year. The overall mortality rates in the nonoperative and operative groups at 1 and 2 years were 9.2% and 16.1% versus 6.7% and 11.3%, respectively. The nonoperative group had a lower overall complication rate of 0.3%, but a higher overall mortality rate compared with the operative group. On average, the nonoperative group was older and had more medical comorbidities including diabetes and peripheral vascular disease.


Most publications on geriatric ankle fractures report favorable outcomes with surgery ( Table 1 ). Makwana and colleagues randomly enrolled 43 patients older than age 55 with displaced ankle fractures after successful reduction into operative and nonoperative treatment groups. The surgical group was treated with a variety of techniques (semitubular plates, rush pins, kirschner wires) and immobilized for 2 weeks in a cast and then transitioned to full weight bearing under the supervision of a physiotherapist. The nonsurgical group was placed in a cast and made non–weight bearing for 6 weeks. Of the 21 patients initially treated with cast immobilization, eight patients required operative fixation for fracture displacement within 3 weeks. The patients within the operative group had better Olerud-Molander Ankle Scores (OMAS) and better ankle range of motion at 2 years of follow-up compared with the nonoperative group. Five patients were noted to have poor bone quality intraoperatively, but stable fixation and good outcomes were achieved in every case.



Table 1

A comprehensive list of outcome studies to date of ankle fracture in the elderly




























































































































Authors LOE Population Outcomes Follow-up Results Recommend Surgery
Beauchamp et al, 1983 Retrospective
Level III
126 patients older than age 50 Clinical examination
Complications
Radiographs
∼2 y High rate of complications (61%), especially in women. 11.3% and 14.1% deep infection and malunion rates, respectively. Allowed early unprotected weight bearing . No, especially in women
Litchfield, 1987 Retrospective
Level IV
31 patients older than age 65 Complications
Radiographs
58% and 19% of patients had satisfactory and poor outcomes, respectively. 12.9% and 16.1% deep infection and malunion complication rates, respectively. Allowed early unprotected weight bearing . No
Ali et al, 1987 Retrospective
Level III
100 patients older than age 60 Pain
Stability
Complications
Radiographs
∼7 y Operative group had better pain control, clinical stability, and fewer malunions. 6% and 8.7% infection and malunion rate in operative group, respectively. Yes
Salai et al, 2000 Prospective
Level II
84 patients older than age 65 AOFAS ∼37 mo AOFAS scores for the surgical group were 75 vs 91 for the nonsurgical group. 32% of surgical group required hardware removal for skin irritation over 2 y. No
Makwana et al, 2001 Prospective
Level I
43 patients older than age 55 Clinical examination
Radiographs
OMAS
VAS
∼27 mo 8 of the 21 patients in the nonoperative group required surgery for fracture displacement in the first 3 weeks. 3 of 22 patients in the operative group underwent removal of symptomatic hardware. OMAS and ankle range of motion were significantly better in the operative group. Low complication rate in operative group. Yes
Srinivasan & Moran, 2001 Retrospective
Level IV
74 patients older than age 70 Complications Length of stay Mobility Residential status Radiographs 85% of patients returned to preinjury mobility and residential status. Preinjury walker-use and open fractures were associated with longer hospital stays. Wound edge necrosis/delayed healing were seen in 9% of cases. Malunion rate of 5%. Deep infection rate of 1%. Osteoporotic bone precluded planned fixation in 12% and were treated in casts for 6–8 wk. Yes
Pagliaro et al, 2001 Retrospective
Level IV
23 patients older than age 65 Complications
Radiographs
∼10 mo One delayed union and wound dehiscence; two amputations; 8% deep infection rate and 4% SSI (one SSI). All complications associated with open injury, PVD, and diabetes. 0% malunion rate. Yes
Vioreanu et al, 2007 Retrospective
Level III
112 patients older than age 70: 72 surgically and 40 with MUA and casting Complications Mobility Additional procedures 16–22 wk Operative treatment was associated with a higher return to preinjury mobility. Wound complications was the most common complication and one patient required a below-knee amputation. Nonoperative treatment was associated with a higher rate of additional surgery and a lower return to preinjury mobility. Yes
Koval et al, 2007 Retrospective
Level III
33,704 patients from Medicare national registry between the ages of 65 and 99 Mortality Complications months after injury
Additional surgery
6 mo–2 y Patients treated operatively had higher rehospitalization rates at all time points. The overall complication rate was 2% at 2 y in the operative group vs 0.3% in the nonoperative group. Revision ankle surgery (internal fixation revision, arthrodesis, amputation) occurred in less than 1% of patients. 11% patients required hardware removal for irritation. Risk factors for increased mortality at 1 y included increasing age, diabetes, and PVD. Low overall complication rates in the nonoperative and operative groups
Fong et al, 2007 Retrospective
Level IV
17 patients older than age 80 Complications
Radiographs
AOFAS
∼18.5 mo Four of the 17 patients had major complications requiring surgery: Two deep infections and two hardware failures. Three of the four complications were caused by patient noncompliance. Yes
Anderson et al, 2008 Retrospective
Level III
25 patients older than age 65 and 46 patients ≤65 y of age Complications
Radiographs
OMAS
SF-36
∼24–27 mo Patients older than age 65 had more medical comorbidities, postoperative complications (40%), and higher need for nursing home placement (64%). Wound complications were the most common postoperative complication (20%). Long-term follow-up showed no difference in patient reported outcomes. Yes
Davidovitch et al, 2009 Retrospective
Level III
313 patients <60 vs 56 patients ≥60 Radiographs
Complications
AOFAS
SMFA
12 mo At 3 months, 57% of patients ≥60 y of reported activity limitations vs 33% of the patients younger than 60. Both groups returned to preinjury functional status. AOFAS scores were not significantly different at 3, 6, or 12 mo. 99% union rate overall at 1 y. 7% vs 13% overall complication rate not statistically different. Yes
Shivarathre et al, 2011 Retrospective
Level IV
82 patients older than age 80 Mobility
Complications
Radiographs
∼15 mo 7% superficial skin infections and 4% of patients developed deep infections requiring hardware removal. Diabetes, dementia, PVD, and smoking were significantly associated with superficial infections. 86% of patients returned to preinjury mobility status at 3–6 mo. Yes
Lynde et al, 2012 Retrospective
Level IV
216 patients older than age 60 Complications Minimum of 6 mo The presence of comorbidities, early weight bearing, or locking vs nonlocking constructs was not correlated with a higher rate of postoperative complications. Complications were more common in older patients (73 vs 69 y of age). Wound dehiscence was the most common complication (10%) and diabetes was the only significant predictor for this complication. Yes

Only gold members can continue reading. Log In or Register to continue

Stay updated, free articles. Join our Telegram channel

Feb 23, 2017 | Posted by in ORTHOPEDIC | Comments Off on Osteoporotic Ankle Fractures

Full access? Get Clinical Tree

Get Clinical Tree app for offline access