Association Between Bone Mineral Density and Elderly Ankle Fractures: A Systematic Review and Meta-Analysis

Bone Mineral Density and Clinical Outcome after Ankle Fracture

BACKGROUND

No gold standard exists for bone mineral density (BMD) measurement of the ankle. This study aimed to determine the correlation between bone density using Hounsfield units (HU) based on computed tomography (CT) and BMD using dual energy X-ray absorptiometry (DXA) as well as to evaluate the correlation between HU and clinical outcome of ankle fracture.

METHODS

Fifty-one patients aged ≥65 years who underwent surgical treatment for trimalleolus or bimalleolus ankle fractures were included. The HU were measured at the distal tibia metaphyseal region approximately 1 cm proximal to the plafond on the axial images of preoperative CT. BMD was measured using DXA within one year before the injury. The clinical outcome was evaluated according to the Foot and Ankle Outcome Score (FAOS).

RESULTS

Although the HU of an osteoporosis group was lower than that of a non-osteoporosis group, we observed no significant difference between the two groups. The mean HU significantly correlated with the lumbar and total lumbar spine BMD using DXA. Increased HU significantly correlated with improved clinical outcomes in three of five FAOS subscales: symptoms, pain, activity of daily living (ADL), and quality of life (QOL). In a linear regression analysis adjusted for age and body mass index, increased HU significantly correlated with improved clinical outcomes in three of five FAOS subscales: symptoms, pain, ADL, and QOL.

CONCLUSIONS

The correlations between bone density using HU and BMD and those between HU and the clinical outcome were confirmed in ankle fractures. The HU of preoperative CT might provide valuable information for predicting postoperative clinical outcomes.

Assessing the content validity of the Manchester-Oxford Foot Questionnaire in surgically treated ankle fracture patients: a qualitative study

BACKGROUND

Roughly 10% of fractures in adults are ankle fractures. These injuries are found in both sexes and present with different fracture characteristics. The treatment varies with the patients' biology and fracture type, and the goals are to restore stability, prevent pain and maintain ankle function. Clinicians generally use outcomes like assessment of radiography, pain level, or function. The use of patient-reported outcome measures is increasing, and the Manchester-Oxford Foot Questionnaire (MOXFQ) has been shown to have good measurement properties when validated in patients with foot and ankle disorders. However, the instrument has not been validated for ankle fracture patients. This study aims to assess the content validity of the items in MOXFQ in surgically treated ankle fracture patients.

METHODS

A qualitative deductive design was used to investigate patients' response process of the MOXFQ. Individual interviews were conducted using cognitive interviewing based on the theoretical framework of the 4-step model by Tourangeau. Adult patients that were surgically treated for an ankle fracture between four weeks and 18 months were purposively sampled, and interviews followed a semi-structured interview guide. The predetermined categories were comprehension, retrieval, judgement, and response.

RESULTS

Seventeen respondents (65% females) were interviewed. Respondents' age ranged from 27 to 76 years. Some of the respondents in the early recovery phase were limited by post-operative restrictions and did not find the items in the walking/standing domain relevant. Respondents that were allowed weight-bearing as tolerated (WBAT) were able to recall relevant information for most items. Respondents with time since surgery more than 12 months had less pain and remembered fewer relevant episodes in the recall period. Items in the social interaction domain contained ambiguous questions and were generally considered less important by respondents. The summary index score lacked important concepts in measuring overall quality of life.

CONCLUSIONS

Pain was a central concept in the post-operative recovery of ankle fracture patients. The MOXFQ-subscales for pain and walking/standing had acceptable content validity in patients that were allowed WBAT. The social interaction-subscale and the summary index score had insufficient content validity for this patient population.

A Comparison of Ankle Fractures Relative to Other Fragility Fractures: A Review and Analysis of the American Orthopaedic Association's Own the Bone Database

BACKGROUND

Ankle fragility fractures (AFX) continue to increase in the elderly population. There is limited knowledge of AFX characteristics compared to nonankle fragility fractures (NAFX). The American Orthopaedic Association's Own the Bone (OTB) is a fragility fracture initiative. This robust data set was used to examine and compare characteristics of patients presenting with AFX to those with NAFX.

METHODS

The OTB database contained 72,617 fragility fractures between January 2009 and March of 2022 and were reviewed in our secondary cohort comparative analysis. After exclusions, AFX accounted for 3229 patients and 54,772 patients were in the NAFX cohort. Bivariate analysis and logistic regression compared the AFX and NAFX groups concerning demographics, bone health factors, medication use, and prior fragility fracture.

RESULTS

AFX patients were found to have a higher likelihood to be younger (67.6 years old), female (81.4%), non-Caucasian (11.7%) and have a higher BMI (30.6) compared to NAFX. Prior AFX predicted the risk of a future AFX. The probability of an AFX increased with increased age and BMI.

CONCLUSION

A prior AFX is independently predictive of subsequent AFX. Therefore, these fractures should be considered a sentinel event. These patients are more likely to have higher BMI, to be of female gender, non-Caucasian race, and are younger compared to patients with NAFX.

LEVEL OF EVIDENCE

Level III, retrospective cohort.

Bone, cognitive, and anthropometric profiles and their relation to fracture sites in fallers: a cross-sectional study

Risk factors involved in the different osteoporotic fracture locations are not well-known. The results of this study suggest that there is not one typical profile characterising a particular fracture site but that the occurrence of a fracture may result from the combination of different bone, cognitive, and anthropometrics characteristics.

PURPOSE

Risk factors involved in the different osteoporotic fracture locations are not well-known. The aim of this study was to identify the differences in bone, cognitive, and anthropometric characteristics between different fracture sites, and to determine whether the site of a fall-related fracture is related to a specific profile.

METHODS

One hundred six women aged 55 years and older with a recent fall-related fracture of the hip (n = 30), humerus (n = 28), wrist (n = 32), or ankle (n = 16) were included. Bone, cognitive, and anthropometric characteristics were first compared among the four fracture site groups. Then, a principal component analysis (PCA) was performed and a comparison was made between the four profiles identified by the first two PCA components.

RESULTS

The four fracture site groups differed significantly in their education level, bone mineral density (BMD), body mass index (BMI), fear of falling, and number of errors in the Trail Making Test B, an executive function test. Each of the four fracture sites was found in each four PCA profiles, albeit with a different distribution. The profiles differed mainly by bone, cognitive, and anthropometric characteristics, but also by fear of falling.

CONCLUSIONS

The fall-related fracture sites differ significantly in anthropometric and bone parameters, in fear of falling and in cognitive abilities. There is not one typical bone, cognitive, and anthropometric profile characterising a particular fall-related site, but rather several possible profiles for a given site. This suggests that the fracture site depends on a combination of several characteristics of the patient.

Identifying the Potential Role of Regional Bone Mineral Density on the Degree of Malleolar Involvement in Acute Ankle Fractures

Ankle fractures are a common traumatic lower extremity injury and are generally classified and characterized by the rotational mechanism of injury. At each malleolus (i.e., posterior, medial, and lateral) a fracture can occur or a ligamentous injury may be sustained. The purpose of this retrospective study was to determine if bone mineral density is a contributing factor on the number of fractured malleoli versus soft tissue injury in adult ankle fractures. Data was obtained from a registry of ankle fractures that were operatively treated by the foot and ankle team throughout our institutional facilities, from July 2017 to August 2019, and in which a preoperative computerized tomography scan was performed. Regional bone mineral density (BMD) was measured by calculating the average Hounsfield Unit (HU) on axial computerized tomography images of the distal fibula and tibia. The average HU was then compared to the number of fractured malleoli. One hundred eight patients met the study criteria. We identified statistically significant relationships between decreased BMD with increasing age (p < .01) and the male gender (p < .01). After adjusting for the covariates age and gender, no statistically significant relationship was identified between BMD and the number of malleoli involved in a given ankle fracture (p = .11). These findings suggest that while more investigation is required for ankle fracture patterns and BMD evaluation, increased age and biologic female gender is significantly related to decreased BMD as identified via HU.

Epidemiology of more than 50,000 ankle fractures in the Swedish Fracture Register during a period of 10 years

BACKGROUND

Despite being one of the most common types of fracture, there is a lack of epidemiological studies involving ankle fractures of all kinds. Since 2012, the Swedish Fracture Register (SFR) has prospectively collected data on surgically and non-surgically treated ankle fractures. The aim of this study is to describe the epidemiology of ankle fractures between 2012 and 2022.

METHODS

All ankle fractures registered in the SFR between 1 April 2012 and 31 March 2022 in patients aged 16 years or older were included. Information on age, sex, mechanism of injury, fracture classification according to AO/OTA and high- or low-energy trauma was retrieved from the SFR.

RESULTS

During the study period, 56,439 patients sustained 57,443 ankle fractures. Women (61%) were more commonly affected than men (39%). The mean age at the time of injury was 55 years. Men were found to be younger at the time of injury compared with women. Women were found to sustain open fractures more frequently, whereas the men more frequently sustained high-energy trauma. The most common mechanism of injury for all ankle fractures and for each AO/OTA44 fracture group separately was a simple fall. A seasonal variation in ankle fractures was found, where the number of ankle fractures peaked during the between November and March.

CONCLUSIONS

This study presents the epidemiology of all AO/OTA types of ankle fractures. We have demonstrated that most ankle fractures are caused by a simple fall and occur during wintertime. Women are more commonly affected than men and are older at the time of injury. These findings indicate that age-related skeletal fragility, as well as an increasing risk of simple falls in the elderly, may be risk factors for ankle fractures. This study will contribute to the planning of primary prevention for ankle fractures.

Ankle fractures: a systematic review of patient-reported outcome measures and their measurement properties

PURPOSE

Ankle fractures are commonly occurring fractures, especially in the aging population, where they often present as fragility fractures. The disease burden and economic costs to the patient and society are considerable. Choosing accurate outcome measures for the evaluation of the management of ankle fractures in clinical trials facilitates better decision-making. This systematic review assesses the evidence for the measurement properties of patient-reported outcome measures (PROMs) used in the evaluation of adult patients with ankle fractures.

METHODS

Searches were performed in CINAHL, EMBASE, Medline and Google Scholar from the date of inception to July 2021. Studies that assessed the measurement properties of a PROM in an adult ankle fracture population were included. The included studies were assessed according to the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) methodology for systematic reviews of PROMs.

RESULTS

In total, 13 different PROMs were identified in the 23 included articles. Only the Ankle Fracture Outcome of Rehabilitation Measure (A-FORM) presented some evidence on content validity. The Olerud-Molander Ankle Score (OMAS) and Self-reported Foot and Ankle Score (SEFAS) displayed good evidence of construct validity and internal consistency. The measurement properties of the OMAS, LEFS and SEFAS were most studied.

CONCLUSION

The absence of validation studies covering all measurement properties of PROMs used in the adult ankle fracture population precludes the recommendation of a specific PROM to be used in the evaluation of this population. Further research should focus on validation of the content validity of the instruments used in patients with ankle fractures.

Ankle fusion with tibiotalocalcaneal retrograde nail for fragility ankle fractures: outcomes at a major trauma centre

PURPOSE

Fragility ankles fractures in the geriatric population are challenging to manage, due to fracture instability, soft tissue compromise, and patient co-morbidities. Traditional management options include open reduction internal fixation, or conservative treatment, both of which are fraught with high complication rates. We aimed to present functional outcomes of elderly patients with fragility ankle fractures treated with retrograde ankle fusion nails.

METHODS

A retrospective observational study was performed on patients who underwent intramedullary nailing with a tibiotalocalcaneal nail. Twenty patients met the inclusion criteria of being over sixty and having multiple co-morbidities. Patient demographics, AO/OTA fracture classification, intra-operative and post-operative complications, time to mobilisation and union, AOFAS and Olerud-Molander scores, and patient mobility were recorded.

RESULTS

There were seven males and thirteen females, with a mean age of 77.82 years old, five of whom are type 2 diabetics. Thirteen patients returned to their pre-operative mobility state, and the average Charlson Co-morbidity Index (CCI) was 5.05. Patients with a low CCI are more likely to return to pre-operative mobility status (p = 0.16; OR = 4.00). All patients achieved radiographical union, taking on average between 92.5 days and 144.6 days. The mean post-operative AOFAS and Olerud-Molander scores were 53.0 and 50.9, respectively. There were four cases of superficial infection, four cases of broken or loose distal locking screws. There were no deep infections, periprosthetic fractures, nail breakages, or non-unions.

CONCLUSION

Tibiotalocalcaneal nailing is an effective and safe option for managing unstable ankle fractures in the elderly. This technique leads to lower complication rates and earlier mobilisation than traditional fixation methods.

Assessment of alternative techniques to quantify the effect of injury on soft tissue in closed ankle and pilon fractures

INTRODUCTION

Local soft tissue status (STS) guides the timing for definitive surgical treatment strategies of fracture fixation around the ankle joint. The aim of this study was to assess different types of new technical devices in relation to the surgical treatment in closed ankle and pilon fractures.

METHODS

This study was designed as a cohort study. Adult patients admitted between February 1, 2019 and December 31, 2020 presenting with closed ankle fracture requiring surgical treatment were eligible. The exclusion criteria were previous injuries to the lower extremity, acute deep venous thrombosis, skin diseases, and delayed presentation (admission >24 hours after injury). Moderate-energy trauma includes injuries sustained during team sports, biking, and running. The primary outcome was the assessment of the degree of soft tissue involvement following closed fractures by comparing different techniques focusing on the ankle region and including ankle and pilon fractures. The variables of interest included the circumference of soft tissue swelling around the ankle, determined within a 5-mm range in the area of the medial and lateral malleolus and the bone-skin distance on a plain radiograph, determined by the largest distance from the malleolus to the border of the soft-tissue shadow. STS assessment included optical measures of local perfusion (O2C, Lea Inc. Germany) and tactile measures of mechanical characteristics (Myoton® tensiometer AS, Estonia). Measurements of Group Temp (temporary stabilization) and Group Def (definitive surgery) were taken on admission and prior to the treatment strategy decision. The contralateral non-injured ankle served as a control. The quality of assessment tools was quantified by calculating the smallest detectable change (SDC).

RESULTS

In total, 38 patients with a mean age of 40.4 (SD 17.8) years were included. The SDC was 3.2% (95%CI 2.5 to 3.8) for local blood flow and 1.1% (95%CI 0.4 to 1.7) for soft tissue stiffness. The circumference of the injured area at admission was significantly higher than that of the healthy site (28.2 [SD 3.4] cm versus 23.9 [SD 2.4] cm, p < 0.001). The local perfusion (blood flow 107.5 (SD 40.79 A.U. vs. 80.1 [SD 13.8] A.U., p = 0.009), and local dynamic stiffness of the skin (668.1 (SD 148.0) N/m vs 449.5 (SD 87.7) N/m, p < 0.001) were significantly higher at the injured site. In Group Temp, the local blood flow was significantly higher when compared with Group Def (109.6 [SD 39.8] vs. 94.5 [SD 13.0], p = 0.023). The dynamic stiffness of the soft tissue was significantly higher in Group Temp (679.4 N/m [SD 147.0] N/m vs. 573.0 N/m (SD 93.8) N/m, p < 0.001). The physical properties of STS were comparable among the fracture types. None of the included patients had local soft tissue complications.

CONCLUSION

Closed fractures of the ankle and the pilon are associated with an increase in local circulation and local soft tissue stiffness and tension. These changes of the STS following injury can be quantified in a standardized and reproducible manner.

The Role of Secondary Imaging Techniques for Assessing Bone Mineral Density in Elderly Ankle Fractures

Elderly ankle fractures in the elderly represent a substantial healthcare burden. Dual-energy x-ray absorptiometry (DXA) is the gold standard for diagnosis of osteoporosis. However, there is emerging research regarding secondary imaging techniques to evaluate bone mineral density (BMD). The purpose of this systematic review was to summarize the role of secondary imaging techniques for measuring BMD in elderly ankle fractures. A literature search was undertaken using relevant search terms. Articles were screened for suitability and data extracted where studies met inclusion criteria and were of sufficient quality. Eight studies were included in the systematic review. Computed tomography (CT) may have a role in preoperative surgical planning, provide an explanation for injury patterns in elderly patients, and may be correlated with clinical outcomes. High-resolution peripheral quantitative CT may be better suited than DXA for the assessment of ankle fractures due to the resolution of the image and its ability to distinguish between bone compartments, as well as provide a more accurate estimation of bone quality. Quantitative ultrasound has shown promise as a tool for measuring BMD in patients with osteoporosis, but is not able to detect osteoporosis in patients with ankle fractures. This paper helps define the role of each modality in the spectrum of care in the evaluation of osteoporosis as it pertains to elderly ankle fractures.

Investigation of the Effect of Bone Mineral Density on the Postoperative Outcome of Ankle Fractures in Elderly Patients

BACKGROUND

The association between ankle fractures in elderly patients and low bone mineral density (BMD) has recently been recognized, but the effect of BMD on the postoperative outcome of these fractures is unknown. The aim of this study was to investigate the effect of BMD on the postoperative outcome of ankle fractures in elderly patients to evaluate the need for BMD screening.

METHODS

We retrospectively reviewed 48 patients aged 65 years or older who had ankle fractures and underwent dual-energy x-ray absorptiometry to assess BMD after surgical treatment of the fracture. Postoperative outcomes were assessed using the Olerud-Molander Ankle Score (OMAS), visual analog scale (VAS) score for pain, Kellgren and Lawrence (K&L) grading scale score, and quality of fracture reduction. The correlation between the BMD and the outcome measures at 12 months after surgery was analyzed using the Pearson correlation coefficient.

RESULTS

The mean absolute value of BMD was 0.6 ± 0.1 g/cm² (T-score, -1.5 ± 1.2) at the femoral neck and 0.8 ± 0.2 g/cm² (T-score, -1.2 ± 1.5) at the lumbar spine. Osteoporosis was present in 33% of female patients and in 11% of male patients. At 12 months after surgery, the OMAS was 70 ± 17 and the VAS score for pain was 18 ± 17. Of the patients, 20, 21, 5, 1, and 1 had K&L grades of 0, 1, 2, 3, and 4, respectively. None of the clinical and radiographic outcome measures were correlated with the BMD values of the patients.

CONCLUSION

The postoperative outcome of the ankle fractures in elderly patients at 12 months after surgery showed no correlation with femoral neck or lumbar spine BMD at the time of fracture.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.