Epidemiology of diaphyseal femoral fracture

Update on Atypical Femoral Fractures

➤ Atypical femoral fractures (AFFs) are stress fractures between the lesser trochanter and the metaphyseal flare that are most commonly related to prolonged (3 to 5 years) antiresorptive medication use.➤ An important finding is a visible transverse line in the lateral cortex, known as the "dreaded black line." Complete fractures are transverse and have minimal comminution.➤ Prodromal symptoms including hip, groin, thigh, and knee pain are present in more than one-half of cases and are usually misdiagnosed.➤ Nonoperative treatment for all patients with AFF includes withdrawal of bisphosphonates, assessment for secondary causes of osteoporosis, and optimization of vitamin D and calcium.➤ Incomplete fractures without a visible line can initially be treated nonoperatively with protected weight-bearing.➤ Intramedullary nailing is indicated for complete fractures and incomplete fractures with a visible fracture line. Delayed healing after fixation should be anticipated.➤ Treatment with parathyroid hormone (PTH) analogs (teriparatide and abaloparatide) after AFF prevents other fractures in high-risk patients, but the effect on healing of the fracture is unclear.

Trend and Economic Implications of Implant Selection in the Treatment of Intertrochanteric Hip Fractures: A Review of the American Board of Orthopaedic Surgery Database From 2007 to 2017

INTRODUCTION

Intertrochanteric (IT) fractures are estimated to burden the healthcare system six billion dollars annually. Previous studies have documented a trend of early-career orthopaedic surgeons favoring intramedullary nails (IMNs) for these fractures, despite multiple randomized controlled trials demonstrating no evidence for improved patient outcomes when compared with sliding hip screws (SHSs). The purpose of this study was to report the trend of implant utilization for IT fracture fixation from 2007 to 2017.

METHODS

The American Board of Orthopaedic Surgery (ABOS) Part II (oral) database was used to identify IT fractures (International Classification of Diseases, 9th revision, code 820.21 or 820.31, and 10th revision, code S72.14) over a 10-year period (2007 to 2017). The cases were categorized by IMN or SHS fixation by surgeon-reported Current Procedural Terminology codes. Utilization of the devices was analyzed according to year, and the implants were compared for outcomes, complications, and cost.

RESULTS

As of 2017, 92.4% of IT fractures were being fixed through IMN, representing a 49.1% increase in the number of IMN devices used during the course of this study. SHS had significantly lower medical complication rate (21.3%) and readmittance rate (4.0%) compared with the IMN (medical complication: 26.9%; P < 0.01) (readmittance rate: 5.4%; P = 0.02). SHS also had significantly lower rates of anemia (5.2%) and patient expiration (4.8%) compared with IMN (anemia: 10.2%; P < 0.01) (patient expiration: 6.1%; P = 0.01). Overall surgical complication rates, reoperative rates, and anesthetic complications did not differ between constructs. A cost differential of $671,812 was found from the 2007-projected distribution, which rose to $3,911,211.00 across the entire 11-year duration of the study for the population.

DISCUSSION

Early-career orthopaedic surgeons continue to use a more expensive implant for IT fractures despite limited evidence for improved outcomes.

LEVEL OF EVIDENCE

Level III; Retrospective Cohort Study.

Responses to Treatment With Teriparatide in Patients With Atypical Femur Fractures Previously Treated With Bisphosphonates

If oversuppression of bone turnover explained the association between bisphosphonate use and atypical subtrochanteric femur fractures (AFF), this could be reversed with anabolic treatment such as teriparatide. We conducted a prospective, open-label study in patients previously treated with bisphosphonates who sustained AFF, examining the response to 24-month treatment with teriparatide on bone mineral density (BMD), trabecular bone score (TBS), bone turnover markers (BTM), and fracture healing as well as quantitative histomorphometry. We studied 14 patients. Baseline BMD, BTM, and TBS varied widely. On initial bone biopsies, 12 of 14 patients showed tetracycline labels, but mineralizing surface/bone surface was below published normal values in all but 2. Lumbar spine BMD increased significantly at month 24 (6.1% ± 4.3%, p < 0.05 versus baseline), whereas total hip BMD and TBS did not change significantly. Changes in BTM occurred as reported previously for patients without AFF treated with teriparatide after prior bisphosphonate treatment. At month 24, fractures were healed in 6 patients, showed partial healing in 3, were unchanged in 2, and showed nonunion in 1. In a patient with two fractures, the fracture that occurred before teriparatide treatment was reported as healed, but the fracture that occurred while on treatment showed only partial healing. Bisphosphonate-treated patients who sustain AFF show heterogeneity of bone turnover. Treatment with teriparatide resulted in increases in BTM and lumbar spine BMD, as has been reported for patients without AFF. There was no significant effect of teriparatide on hip BMD, mineralizing surface to bone surface (MS/BS), or TBS and no consistent effect on fracture healing. In the context of a patient who has experienced an AFF after receiving bisphosphonate treatment, therapy with teriparatide for 24 months would be expected to increase BMD and BTM (and probably reduce the risk of fractures resulting from osteoporosis) but should not be relied on to aid in healing of the AFF. © 2017 American Society for Bone and Mineral Research.

Intraoperative Distal Femoral Fine Wire Traction to Facilitate Intramedullary Nailing of the Femur

Many techniques have been employed to facilitate intramedullary nailing of femur fractures. Maintaining limb length during the operation can be difficult. The authors describe the use of distal femoral fine wire skeletal traction as a technique to maintain reduction while allowing intramedullary nailing of femur fractures. This technique is safe, is effective, and negates the need for a fracture table or an assistant.

Training effect of using Touch Surgery for intramedullary femoral nailing

BACKGROUND

Simulation in orthopaedic training is becoming increasingly popular and has been widely used in formal curricula. However, these resources are expensive and not easily accessible to every trainee. Other means of disseminating surgical education through virtual reality (VR) multimedia can act as useful adjunct to traditional methods of teaching. One validated VR platform is Touch Surgery, a cognitive task simulation and rehearsal app.

OBJECTIVES

The primary objective of this study was to identify the training effect of Touch Surgery intramedullary femoral nailing (IFN) modules using objective performance metrics over six consecutive attempts. Secondary objectives consisted of validated multiple choice questions (MCQ) testing before the first (pre) and after the sixth (post) attempts.

METHODS

27 medical undergraduates were recruited to complete the decision-making process six consecutive times for four modules on the procedural steps of IFN. The modules consisted of (i) preparing the patient and equipment, (ii) femoral canal preparation, (iii) nail insertion and proximal locking, and (iv) distal locking and closure. Real-time objective performance metrics were obtained, stored electronically and analysed using the median and Bonett-Price 95% confidence intervals from the participants' attempts to assess training effect. Significance was calculated using the Mann-Whitney U test for independent data whilst the Wilcoxon signed ranked test was used for paired data. Significance was set as 2-tailed p-value <0.05.

RESULTS

Median performance scores per attempt for all four modules demonstrated a significant improvement ranging from 58 to 115%. Scoring variability and distribution was reduced and more predictable per attempt. Logarithmic learning curves elicited strong positive correlations between the number of attempts and scoring. Mean scores for pre and post-study MCQs tests significantly improved from 83 to 94% in all modules.

CONCLUSION

IFN modules on Touch Surgery app demonstrated a significant training effect with practice. Novices demonstrated cognitive competencies to ensure patient safety prior to operating. The app is an effective adjunct to traditional learning methods and has the potential for curricular implementation.

Proceedings of the 2015 Santa Fe Bone Symposium: Clinical Applications of Scientific Advances in Osteoporosis and Metabolic Bone Disease

The 2015 Santa Fe Bone Symposium was a venue for healthcare professionals and clinical researchers to present and discuss the clinical relevance of recent advances in the science of skeletal disorders, with a focus on osteoporosis and metabolic bone disease. Symposium topics included new developments in the translation of basic bone science to improved patient care, osteoporosis treatment duration, pediatric bone disease, update of fracture risk assessment, cancer treatment-related bone loss, fracture liaison services, a review of the most significant studies of the past year, and the use of telementoring with Bone Health Extension for Community Healthcare Outcomes, a force multiplier to improve the care of osteoporosis in underserved communities.

Validating Touch Surgery™: A cognitive task simulation and rehearsal app for intramedullary femoral nailing

BACKGROUND

The role of simulation in orthopaedic surgical training is becoming increasingly evident, as simulation allows repeated sustained practice in an environment that does not harm the patient. Previous studies have shown that the cognitive aspects of surgery are of equal if not greater importance in developing decision making than the practical aspects.

AIM

To observe construct, content and face validity of four IFN modules on a cognitive simulator, Touch Surgery™.

METHODS

39 novices and 10 experts were recruited to complete four simulation modules on surgical decision-making that represented the procedural steps of preparing the patient and equipment, inserting and locking an intramedullary femoral nail. Real-time objective performance metrics were obtained, stored electronically and analysed using median and Bonett-Price 95% confidence intervals from the participant's primary attempt to assess for construct validity. The median score of a post-study questionnaire using 5-point Likert scales assessed face and content validity. Data was confirmed as non-parametric by the Kolmogorov-Smirnov test. Significance was calculated using the Mann-Whitney U test for independent data whilst the Wilcoxon signed ranked test was used for paired data. Significance was set as 2-tailed p-value<0.05.

RESULTS

Experts significantly outperformed novices in all four modules to demonstrate construct validity (p<0.001). Specifically, experts scored 32.5% higher for patient positioning and preparation (p<0.0001), 31.5% higher for femoral canal preparation (p<0.0001), 22.5% higher for proximal locking (p<0.0001) and 17% higher scores for distal locking and closure (p<0.001). Both cohorts either agreed or strongly agreed that the graphics, simulated environment and procedural steps were realistic. Also, both cohorts agreed that the app was useful for surgical training and rehearsal, should be implemented within the curriculum and would want to use it to learn other surgical procedures.

CONCLUSION

IFN on the Touch Surgery app demonstrated construct, face and content validity. Users can demonstrate cognitive competencies prior to performing surgical procedures in the operating room. The application is an effective adjunct to traditional learning methods and has potential for curricular implementation.

Bisphosphonate-associated atypical sub-trochanteric femur fractures: paired bone biopsy quantitative histomorphometry before and after teriparatide administration

OBJECTIVES

Bisphosphonate-associated atypical sub-trochanteric femur fractures (ASFF) may be seen with long-term bisphosphonate use, though these fractures are also seen in patients never exposed to bisphosphonates. One theory for the mechanism of action whereby bisphosphonates may induce these ASFF is over-suppression of bone turnover. Bisphosphonates suppress bone turnover, but in bisphosphonate clinical trials, over-suppression defined whether by maintaining the biochemical markers of bone turnover below the defined reference range or by quantitative bone histomorphometry, has not been observed.

METHODS

We studied 15 clinic patients referred to The Colorado Center for Bone Research (CCBR) after they had a bisphosphonate-associated ASFF and performed quantitative bone histomorphometry both before and after 12 months of teriparatide (20µg SQ/day). All patients had been on long-term alendronate (mean = 7 years, range: 6-11 years) and had already had intramedullary rods placed when first seen (6 weeks to 7 months after rod placement). Alendronate had been discontinued in all patients at the time of their first clinic visit to CCBR. All of the fractures fulfilled The American Society for Bone and Mineral Research major radiological criteria for ASFF.

RESULTS

Three key dynamic histomorphometric features show that 7 of the 15 patients had unmeasurable bone formation, mineralizing surface, and mineral apposition, while the other 8 patients had measurable dynamic parameters; although for all 15 patients, the mean values for all 3 dynamic parameters was far below the average for the published normal population. Administration of teriparatide was associated with an increase in all 3 dynamic histomorphometric parameters. Baseline bone turnover markers did not correlate with the baseline histomorphometry. While there is heterogeneity in the bone turnover in patients with bisphosphonate ASFF, there is a large portion in this uncontrolled series that had absent bone turnover at the standard biopsy site (iliac crest). Discontinuation of the bisphosphonate and administration of the anabolic agent, teriparatide was associated with improvement in bone turnover.

CONCLUSIONS

While our study does not establish causality or address the ability of teriparatide to prevent progression of early stress fracture to displaced fractures, it does suggest that teriparatide may improve bone formation in these patients. Our study should stimulate other investigations using larger sample sizes and early stress fractures to see if anabolic agents can reverse these fractures from becoming displaced.

Investigation of a fatigue failure in a stainless steel femoral plate

Surgical implants are exposed to severe working conditions and therefore a wide range of failure mechanisms may occur, including fatigue, corrosion, wear, fretting and combinations of them. The mechanical failures of metallic implants may also be influenced by several other factors, including the design, material, manufacturing, installation, postoperative complications and misuse. An 83-year-old patient suffered an oblique femoral shaft fracture due to a fall at home. A stainless steel locking compression plate (LCP) employed in the fracture reduction failed after four months and was sent back to the producer. A second LCP of the same type was implanted and also failed after six months. A failure analysis of the second femoral LCP is performed in this paper. The results demonstrate that poor material quality was decisive to the failure. The chemical analysis revealed a high P content in the steel, which is not in accordance to the standards. A combination of factors lead to LCP fracture and these include: brittle crack initiation due to phosphorus, segregation at grain boundaries, crack propagation due to cyclic loading and final fast fracture favored by the loss of ductility due to cold work.

Concomitant ligamentous and meniscal knee injuries in femoral shaft fracture

Background

Concomitant knee injury is a common finding in femoral fractures but can be easily missed during early management of the initial trauma. Degrees of damage to the articular structures vary considerably; from only a mild effusion to complete ligamentous and meniscal tears. Since previous reports were mostly from developed societies, this study was designed to look into characteristics of associated knee injury in a sample from Iran, to represent a developing country perspective.

Materials and methods

Consecutive patients admitted to an orthopedic ward of Baqiyatallah hospital (Tehran, Iran) with diagnosis of femoral fracture were enrolled in this study between October 2008 and September 2009. In patients who met the inclusion criteria of the study, arthroscopic or open surgical examination of the knee, ADT, Lachman test, varus and valgus stress tests under anesthesia were carried out to determine the incidence of knee injury.

Results

Forty patients with ipsilateral and two patients with bilateral femoral fractures were studied. Arthroscopy revealed medial meniscus injury in 12 (27 %) knees. Three (7 %) lateral meniscus injuries, 18 (40.9 %) ACL injuries and 2 (4.5 %) PCL injuries were also found. In varus and valgus stress tests, 15 (34 %) MCL and 4 (9 %) LCL laxities were noticed. The Lachman test was positive in 3 (6 %), and ADT was positive in 2 (4.5 %) patients.

Conclusions

Based on our observations, concomitant ligamentous and meniscal knee injury is a common finding in femoral shaft fractures and rates of these injuries are generally in concert with reports from developed nations.

Risk factors for subtrochanteric and diaphyseal fractures: the study of osteoporotic fractures

CONTEXT

Patients on long-term bisphosphonate therapy may have an increased incidence of low-energy subtrochanteric and diaphyseal (SD) femoral fractures. However, the incidence and risk factors associated with these fractures have not been well defined.

OBJECTIVE

The objective of the study was to determine the incidence of and risk factors for low-energy SD fractures in the Study of Osteoporotic Fractures (SOF).

DESIGN

Low-energy SD fractures were identified from a review of radiographic reports obtained between 1986 and 2010 in women in the SOF. Among the SD fractures, pathological, periprosthetic, and traumatic fractures were excluded. We assessed risk factors for SD fractures as well as risk factors for femoral neck (FN) and intertrochanteric (IT) hip fractures using both age-adjusted and multivariate time-dependent proportional hazards models. During this follow-up, only a small minority had ever used bisphosphonates.

RESULTS

Forty-five women sustained low-energy subtrochanteric/diaphyseal femoral fractures over a total follow-up of 140 000 person-years. The incidence of SD fracture was 3.2 per 10 000 person-years compared with a total hip fracture incidence of 110 per 10 000 person-years. A total of about 12% of women reported bisphosphonate use at 1 or more visits. In multivariate analyses, age, total hip bone mineral density (BMD), bisphosphonate use, and history of diabetes emerged as independent risk factors for SD fractures. Risk factors for FN and IT fractures included age, BMD, and history of falls or prior fractures. Bisphosphonate use was protective against FN fractures, whereas there was an increased risk of SD fractures (hazard ratio 2.58, P = .049) with bisphosphonate use after adjustment for other risk factors for fracture.

CONCLUSIONS

In SOF, low-energy SD fractures were rare occurrences, far outnumbered by FN and IT fractures. Typical risk factors were associated with FN and IT fractures, whereas only age, total hip BMD, and history of diabetes were independent risk factors for SD fractures. In addition, bisphosphonate use was a marginally significantly predictor although the SOF study has limited ability to assess this association.

Trends in subtrochanteric, diaphyseal, and distal femur fractures, 1984-2007

The incidence of non-hip femur fractures increased between 1984 and 2007, with an increase in the rates for women after 1996.

INTRODUCTION

Recent reports have suggested that non-hip femur fractures may be decreasing over time, similar to proximal femur fractures.

METHODS

Incidence rates for non-hip femur fractures among Olmsted County, Minnesota, residents were assessed before and after 1995 when the oral bisphosphonate, alendronate, was approved in the USA.

RESULTS

From 1984 to 2007, 727 non-hip femur fractures were observed in 690 Olmsted County residents (51% female [median age, 71.6 years] and 49% male [21.4 years]). Altogether, 20% of the fractures were subtrochanteric, 51% were diaphyseal, and 29% involved the distal femur. Causes included severe trauma in 51%, minimal to moderate trauma in 34%, and pathologic causes in 15%. The overall age- and sex-adjusted annual incidence of first non-hip femur fracture was 26.7 per 100,000 (25.0 per 100,000 for women and 26.6 per 100,000 for men). Incidence rates increased with age and were greater in women than men. Between 1984-1995 and 1996-2007, age-adjusted rates increased significantly for women (20.4 vs. 28.7 per 100,000; p = 0.002) but not for men (22.4 vs. 29.5 per 100,000; p = 0.202).

CONCLUSION

The incidence of first non-hip femur fractures rose between 1984 and 2007, with an increase in the rates for women after 1995.

The impact of subtrochanteric fracture criteria on hip fracture classification

SUMMARY

Hospital diagnosis codes are useful for assessing hip fracture rates in large populations. However, these codes do not reliably differentiate hip fractures that occur in the subtrochanteric region. Identification of subtrochanteric fractures requires review of radiographic images to distinguish these fractures from the more commonly occurring trochanteric fractures.

PURPOSE

This study examines the accuracy of coded hospital diagnoses for hip fracture compared to fracture site verification based on operative and radiologic data. The variability in subtrochanteric fracture assignment was also examined using different anatomic criteria.

METHODS

This retrospective study includes female members of Kaiser Permanente Northern California age 60 years and older with nontraumatic hip fracture during 2007-2008. Anatomic site was verified by operative and radiologic records, including radiographic image review for fractures occurring in the subtrochanteric region. Two different criteria were compared for subtrochanteric fracture.

RESULTS

We identified 2,824 women with incident hip fracture during the 2-year period. The average age was 82.9 ± 8.2 years and 15% were non-White. International Classification of Diseases, Ninth Revision (ICD-9) coding was accurate for femoral neck and trochanteric fractures (>90% confirmed by operative/radiologic reports), compared to only 26% for subtrochanteric fractures using the Orthopedic Trauma Association (OTA) criteria for subtrochanteric fracture. Using OTA classification, 1.3% of hip fractures were assigned as subtrochanteric compared to 4.2% when the criteria were broadened to include the lesser trochanter. Both femoral neck and pertrochanteric fracture rates increased exponentially with age, while age-related rates in subtrochanteric fracture differed by diagnostic classification method; the broader criteria including the lesser trochanter produced age-related trends that mirrored femoral neck and pertrochanteric fractures.

CONCLUSION

Unlike femoral neck and pertrochanteric fractures, epidemiologic studies of subtrochanteric fractures cannot rely on ICD-9 codes alone. Review of radiologic images using OTA criteria is required for identification of subtrochanteric fractures occurring below the lesser trochanter.

Subtrochanteric/femoral shaft versus hip fractures: incidences and identification of risk factors

Subtrochanteric and femoral shaft (ST/FS) fractures are now considered to be fragility fractures in osteoporotic patients. Although rare, there is growing evidence of the burden that they constitute. Little is known about the change over time in incidence of ST/FS fractures. We assessed the incidence of ST/FS fractures and the associated risk factors from 2002 to 2009 compared with those of hip fractures. Data were obtained from the French National Database, which includes all hospital discharge codes from acute care facilities. Hospitalizations for primary surgical management of neck/trochanteric (hip) and ST/FS fractures in patients aged above 50 years were selected and described for different age groups. Incidences per million populations were calculated using the estimated French population adjusted for each year, age, and gender. We studied the change for each fracture site. The comorbidity factors related to these fractures were assessed in 2009 using multivariate logistic regression. From 2002 to 2009, the adjusted incidence of hip fractures decreased continuously from 4368 to 3662 in women (p < 0.0001), and a mild increase from 1476 to 1384 in men (p < 0.0001) after an initial decrease. In contrast, the incidence of ST/FS increased significantly in both genders (from 353 to 395 in women, from 146 to 159 in men). In 2009, the incidence of ST/FS in the general population remained low, reaching the levels of 412 in women and 168 in men, but were 2966 and 1461 in women and men aged >89 years. The adjusted risk of having a ST/FS fracture was significantly higher in a context of obesity (odds ratio [OR]: 2.26; 1.95-2.61) and dementia (OR: 1.23; 1.16-1.30), but decreased with age (OR: 0.83; 0.79-0.88) and hypertension (OR: 0.90; 0.86-0.95). In conclusion, ST/FS fractures mainly affect elderly people and incidence increased significantly from 2002 to 2009. Obesity and dementia are the risk factors associated with these rare fractures, compared with regular hip fractures.

Atypical fractures and bisphosphonate therapy: a cohort study of patients with femoral fracture with radiographic adjudication of fracture site and features

Atypical subtrochanteric/femoral shaft (ST/FS) fractures are increasingly reported in patients on long-term treatment with bisphosphonates (BPs). We estimated the frequency of atypical fractures and their association to BP use in patients aged ≥ 50 years consecutively admitted to a single center with a new femoral fracture. All individual radiographs were examined and fracture site confirmed. A case-control study of patients with low-energy ST/FS fractures, age- and sex-matched with patients with hip fractures (1:2 ratio), was performed. Patients with atypical ST/FS fractures were further compared with those with ordinary ST/FS fractures. Cortical thickness (CT) was measured in radiographs of cases and controls. Ninety-six of 906 patients (10.6%) had a ST/FS fracture. Of these, 63 with low-energy fractures were individually matched with 126 controls with hip fracture. BPs were used by 9.5% of cases and by 8.7% of controls (OR, 1.10; 95% CI, 0.39-3.06) with comparable duration of therapy between groups (54 ± 35 vs. 54 ± 52 months, P=0.53). CT was comparable between cases and controls, BP users and non-users, and was not related to treatment duration. Atypical fractures were observed in 10/63 ST/FS cases (15.9%). Compared to patients with ordinary ST/FS fractures, those with atypical fractures were using more frequently BPs (OR, 17.0; 95% CI, 2.6-113.3) and glucocorticoids (OR, 5.3; 95% CI, 0.9-28.6). Among patients with atypical fractures, CT was comparable between BP users and non-users. In conclusion, atypical femoral fractures have a low prevalence (1.1% of all femoral fractures), compared to ordinary ST/FS fractures are more frequent in bisphosphonate users, but equally occur in patients never treated with bisphosphonates.

[Pediatric femur fractures, epidemiology and treatment]

BACKGROUND/AIM

Femur fractures in children most often occur as a consequence of traffic accidents, during play and sport activities, and due to different pathological states. Diagnosis is rather simple and it includes physical and radiographical examination. Femur fractures treatment in children can be operative and unoperative, depending on several facts: age, localisation and type of fracture, joint injuries of soft tissues, the presence of other injuries (in polytrauma), economical and social aspects, ect. The aim of this study was to present epidemiological characteristics of pediatric femur fractures, that is in the stage of development, including a special analysis of the used treatment techniques, as well as the comparison of the obtained data with those from the literature.

METHODS

The evaluation included following parameters: age, gender, cause, localisation and type of femur fracture, applied treatment and hospitalisation duration.

RESULTS

Among the presented 143 patients with femur fracture, 109 were boys and 34 were girls (3.2:1 ratio; p = 0.0001). Average age for both genders was 8.6 years, and no difference between boys and girls were found for the age (p = 0.758). In total, the most common fracture was diaphyseal fracture of femur in 93 (65.03%) patients. The second was proximal fracture in 30 (20.98%) patients, and the last distal fracture of the femur in 20 (13.99%) patients (p = 0.0001). Three main causes of femur fracture can be distinguished: during play and sport activities in 67 (46.8%) children, in traffic accidents in 64 (44.8%) children, and pathological fractures in 12 (8.4%) children. Inoperative treatment was applied in 82 (57.3%) patients, and operative one in 61 (42.7%) patients. The most common treatment was traction, in 71 (49.6%) patients, followed by immobilization by hip spica cast mostly in young children. Intramedullar elastic nailing was applied in 16 (11.2%) cases, and intra-medullar rigid nailing (Küntscher) in 19 (13.3%) cases. Significantly longer hospitalization period was detected after traction (21 days) comparing to other ways of treatment, mainly operative or hip spica cast (5 to 10 days).

CONCLUSION

In young children the standard treatment was hip spica cast after traction. Intramedullar elastic nailing is a modern trend accepted as standard in our approach to femur fracture treatment in children.

Fragility fractures of the hip and femur: incidence and patient characteristics

SUMMARY

Using national discharge and medical claims data, we studied the epidemiology of femoral fractures from 1996 to 2006. The annual hip fracture incidence declined from 600/100,000 to 400/100,000, without decline in the more rare femur fractures. Incidence rates for subtrochanteric and femoral shaft fractures were each below 20 per 100,000.

INTRODUCTION

This study's purpose is to describe the site-specific epidemiology of femur fractures among people aged 50 and older.

METHODS

Using the National Hospital Discharge Survey from 1996 to 2006 and a large medical claims database (MarketScan), we studied epidemiology of all femur fractures. Hip fractures were grouped together; subtrochanteric, shaft, and distal femur fractures were kept separate.

RESULTS

In females, the overall hospital discharge rates of hip fracture decreased from about 600/100,00 to 400/100,000 person-years from 1996 to 2006. Subtrochanteric, femoral shaft, and lower femur rates remained stable, each approximately 20 per 100,000 person-years. Similar trends but lower rates existed in males. No significant trends were found in any of these fractures during the more recent years of 2002-2006 (MarketScan data). Using MarketScan, the overall incidence of hip fracture was <300/100,000 person-years; incidence of subtrochanteric and femoral shaft fractures combined was <25/100,000 person-years and distal femur fracture incidence was <18/100,000 person-years in females; rates were lower in males. The incidence of hip and other femur fractures increased exponentially with age.

CONCLUSIONS

We found no evidence of an increasing incidence of any femoral fracture. Hip fracture incidence is declining but the incidence of each of the more rare femur fractures (distal to the lesser trochanter) is stable over time.

Resultados do tratamento das fraturas da diáfise do fêmur ipsilaterais às do colo ou transtrocantérica

OBJETIVO: Avaliação radiográfica, funcional e das complicações do tratamento cirúrgico das fraturas diafisárias do fêmur associadas à fratura transtrocantérica ou do colo do mesmo fêmur. MÉTODOS: De 2002 a 2007 foram tratados 17 pacientes. Eram masculinos 88% e a idade média foi de 31 anos e três meses. Dez (59%) apresentavam associação com fratura do colo do fêmur e sete (41%) com a fratura transtrocantérica. Foram avaliados a dor residual e a amplitude de movimento articular do quadril e joelho, a consolidação radiográfica e o tipo de implante utilizado, pela avaliação atual e retrospectivamente pelo prontuário, com um seguimento médio de 48 meses. RESULTADOS: Todas as fraturas transtrocantéricas evoluíram para consolidação sem deformidade residual. Das fraturas do colo, três (30%) apresentaram retardo da consolidação, e duas consolidaram em varo. Dois pacientes apresentaram retardo de consolidação da fratura diafisária. Todas as fraturas associadas trans-diáfise apresentaram resultado funcional excelente ou bom. Das associadas colo-diáfise, sete (70%) apresentaram resultado funcional excelente ou bom, dois regular e um ruim. CONCLUSÃO: As fraturas associadas da diáfise do fêmur com fratura transtrocantérica apresentaram melhor resultado radiográfico e funcional com menos complicações que a associação da fratura diafisária com a fratura do colo do fêmur

National data of 6409 Swedish inpatients with femoral shaft fractures: stable incidence between 1998 and 2004

INTRODUCTION

Femoral shaft fractures are commonly thought to be primarily associated with high-energy trauma in young persons. Only limited attention has been given to low-energy violence as a cause of these fractures among the elderly. National epidemiological data on characteristics of patients with femoral shaft fractures are lacking, so the purpose of this study was to analyse the incidence, admissions, causes of fracture and operations for these fractures on a nationwide basis in Sweden during 1998-2004.

PATIENTS AND METHODS

Data on all femoral shaft fractures were extracted from the Swedish National Hospital Discharge Registry. Sex- and age-specific fracture incidence, hospital admissions, mechanisms of injury and surgical procedures were analysed using descriptive analysis, linear-regression analysis and other methods as appropriate.

RESULTS

Over a period of 7 years, 6409 patients with femoral shaft fractures were identified, corresponding to an annual incidence of 10 per 100,000 person-years. Men had a younger median age (27 years, IQR 12-68) than women (79 years, IQR 62-86) (p<0.001). Females (54%) generated more admissions than males (46%). The incident rate ratio between men and women was 0.9 (p<0.001). Most hospital admissions were generated among females by the 80-89 years age-group and among males <10 years of age. 2% of the fractures were open fractures. The total number of hospital admissions was stable during 1998-2004. The two major mechanisms of injury were falls on the same level (50%) and transport accidents (17%). A significant number of fractures occurred among elderly patients after low-energy trauma. Osteosynthesis with femoral nail (54%) was the preferred operation, followed by osteosynthesis with plate and screws (16%), skeletal traction (14%) and external fixation (6%).

DISCUSSION

This nationwide study on femoral shaft fractures provides an update on incidence, admissions, external causes and surgical procedures. This information assists health-care providers in planning hospital beds, surgical interventions and risk preventions. Moreover, these data can be used for power calculations for further clinical studies.

Characteristics of long bone DXA reference data in Hong Kong Chinese

With the increasing number of geriatric long bone fractures, the establishment of long bone reference BMD data is desirable for the accurate diagnosis of osteoporosis, study of fracture mechanics, implant design, and indications for augmentation of fracture fixation with biomaterials. We report the normal reference bone mineral density (BMD) and bone mineral content (BMC) at three femoral sites (proximal, diaphyseal, and distal) in 106 male and 93 female Hong Kong Chinese aged 12 to 80, measured with dual-energy X-ray absorptiometry (DXA). The length and width of the femur were also measured. The results suggest that males reached peak bone mass earlier than females and the value was also higher in all measured sites. After reaching the peak bone mass, bones lost BMD faster in females. The age-related annual bone loss (in BMD) calculated with a regression model in female subjects were, on average, 3.3, 4.0, and 3.0 times higher than those in males at the diaphyseal, proximal, and distal regions, respectively. The decrease in BMD and BMC occurred slightly earlier in the proximal and distal regions than the diaphysis in both sexes. The male femur was significantly longer than that of the female in all age groups after 20 yr of age and remained unchanged with advancing age. The femoral width in females showed an increasing trend from adolescence. Our study provides reference data for the changes in diaphyseal BMC and BMD associated with aging. The age-related changes in the femoral diameter in females might attenuate the negative impact on fracture risk as a result of decreasing BMD with age.

Population based epidemiologic and morphologic study of femoral shaft fractures

The epidemiologic and morphologic features of all femoral shaft fractures in skeletally mature patients treated during a 10-year period in a semi-urban county were analyzed. Among an average adult population of 202,592 residents, 192 people sustained 201 traumatic femoral shaft fractures during the study period. The incidence was 9.9 fractures per 100,000 person-years. The highest age and gender specific incidences were seen in males from 15 to 24 years of age and in females 75 years of age or older. Seventy-five percent (151) of the fractures were the result of a high-energy trauma, 131 of which occurred in road traffic accidents. Unexpectedly, there were 50 low-energy fractures. Fractures of the middle 1/3 of the diaphysis were 79%. The majority, 155 (77%), of all fractures were transverse, oblique, or oblique transverse. Regarding the degree of comminution, the Winquist and Hansen Grade 0 (noncomminuted) fracture was the most common. Forty-eight percent of fractures were AO Type A, 39% were Type B, and 13% were Type C fractures. Of the 25 open fractures, 14 were Gustilo Type II. All six Type III open injuries were Type IIIA. Based on the data from the current study, most of the femoral fractures in this community might be treated adequately with conventional intramedullary nails, rather than using interlocking nails, provided the stability of fixation and fracture alignment can be maintained. Preventive measures against femoral shaft fractures should focus on protection of automobile drivers, especially young men, and on effective treatment of osteoporosis in elderly women.

Specific features associated with femoral shaft fractures caused by low-energy trauma

OBJECTIVE

To scrutinize the fracture patterns of femoral shaft fractures caused by low-energy injury mechanism and to delineate the problems associated with the treatment of these fractures.

MATERIALS AND METHODS

Of a total of 192 consecutive skeletally mature patients with 201 acute fresh femoral shaft fractures admitted during a 10-year period (1985-1994), 50 patients had a fracture caused by low-energy trauma. The fractures were classified in terms of their configuration, site, degree of comminution, and soft-tissue injury. The previous fractures, chronic illnesses, and continuous medications of the patients as well as the injury mechanisms and concomitant injuries were registered. All general and local complications and their consequences were recorded. Forty patients could be followed until the bony union of the fracture was achieved, the mean follow-up time being 14 months.

RESULTS

The incidence of these injuries was 2.5 per 100,000 person-years. There were 32 women and 18 men. The mean age of the patients was 65 years (range, 17-92 years). Thirteen patients were younger than 60 years of age. Thirty-two (64%) had at least one local or general factor weakening the mechanical strength of the bone that predisposed them to a fracture. Thirty-two patients sustained a fracture of the left femur (p < 0.05). All fractures were closed. None of the patients had significant concomitant injuries. In 33 cases, the site of the fracture was in the middle third of the femur. The fracture configuration was spiral in 29, transverse in 10, oblique-transverse in 7, and oblique in 4 cases. Postoperative complications, including delayed union, nonunion, and malunion, occurred with 29 patients. Eighteen reoperations among 12 patients were performed because of these complications.

CONCLUSIONS

Femoral shaft fractures caused by low-energy violence occur mainly in patients suffering from a chronic disease or a condition causing osteopenia of the femur. The most common fracture pattern was a spiral one in the middle third of the femoral shaft. Despite the low-energy violence, the treatment of these fractures is not devoid of complications. The treatment of these seemingly simple fractures requires careful planning and meticulous operative technique.

The accumulation of fatigue microdamage in human cortical bone of two different ages in vitro

OBJECTIVE

To analyse the development of damage during fatigue cycling of human bone.

DESIGN

Changes in compliance and the cycles to failure were monitored in cortical bone samples subjected to oscillating stress in vitro.

BACKGROUND

Previous studies produced mainly the relationship between the applied stress and the final cycles to failure (sigma-N(f)plots). However, cyclic stressing increases the compliance of the bone continuously, and causes a progressive mechanical/structural degradation. Recording this accumulation of damage allows one to know how close bone is to the point of failure; more importantly, it allows a more comprehensive modelling of fatigue processes in cortical bone.

METHODS

The occurrence of material damage was continuously monitored during the tests. The 20 specimens came from two female subjects, 27 and 56 years old. The range of the cyclic stresses was 58-130 MPa.

RESULTS

The damage was quantified with a graphical and an empirical/numerical method, and we have also microscopically observed the generation of internal microcracks. The range of cycles to failure was from 1 to 210,000.

CONCLUSIONS

It was observed that (i) the older tissue showed a lower fatigue strength than the younger one, (ii) both tissues sustained similar damage levels prior to failure, and (iii) they both showed a continuous accumulation of damage during the tests, the course of which depended on the level of stress.

The epidemiology of peripheral fractures

Although much is known about hip fracture epidemiology, there are relatively little data regarding fractures at other peripheral sites. Epidemiological differences between fractures are important, since they imply that an understanding of the consequences and clinical expression of osteoporosis requires the study of many different fracture types. Recent data regarding the basic epidemiology of limb fractures among the elderly in industrialized countries have made some patterns clear. Fractures outside the hip are relatively common events, and before age 70 to 75, ankle and distal forearm fractures occur more commonly than fractures of the hip. Among the elderly, fractures at the most proximal and most distal ends of the limbs have the highest incidence. Thus, in the upper extremity, fractures of the proximal humerus and distal forearm are the most common, while in the lower extremity, those at the hip and ankle predominate. Outside the axial skeleton, females have higher rates for most fracture types, and at most fracture sites whites have higher rates than blacks. In each limb, the most proximal fractures tend to have the most pronounced age-related increases in risk.

Bending strength of the femur in relation to non-invasive bone mineral assessment

To analyze the importance of bone mineral for the strength of the distal diaphyseal femur, we studied 14 distal cadaver femora by quantitative computed tomography, (QCT) dual energy X-ray (DXA) absorptiometry and three-point bending. The femora were retrieved at autopsy from 10 male and 4 female donors aged median 74 yr (range 59-92 yr). Significant correlations were found between three bone mineral mass related parameters--QCT bone mass (density x slice area), DXA mineral density (BMD) and content (BMC)--and mechanical parameters. Second area moment equivalents correlated significantly with the mechanical properties of the distal femur. QCT density did not show the same high correlations. The results indicate that the structural strength of diaphyseal bone is determined more by its geometry than mineral density. Assessment of bone mass by QCT or DXA may become important not only for assessment of fracture risk but also for planning of internal fixation in the treatment of osteporotic fractures. Further studies are required to investigate the clinical importance of these observations.

Retention of distal femoral osteotomy fixed with a AO condylar plate and Grosse-Kempf locked nail in relation to bone mineral in cadavers

On the basis of previous studies showing good correlations between the structural strength of the femur and bone mass as assessed by single energy quantitative computed tomography, this study was scheduled to analyze the mode of failure of an oblique osteotomy in the distal femur in geriatric cadavers stabilized by an AO condylar plate and Grosse-Kempf locked intramedullary nail in axial eccentric loads and to relate the mode of failure to bone mineral content. A pilot study of two pairs of osteotomized, internally fixed femora were loaded axially and the loads correlated with bone mineral content. These correlations were used to calculate estimated failure load in 12 pairs of osteotomized femora (12 plated and 12 nailed specimens) which then were sustained to a cyclic eccentric axial load of 50% of the estimated failure load. The failure patterns in the two groups were different. Fixation failure occurred in all specimens in the plated group at the site of the osteotomy, while in the nailed group the fixation failures in 50% of the specimens were unrelated to the site of the osteotomy. The study suggests that locked intramedullary nailing of a distal femoral fracture in osteoporotic bone gives more secure fracture retention than fixation with a 95 degrees AO/ASIF condylar plate. Furthermore, it shows that bone mineral assessment by densitometric methods can be used to predict the mechanical strength of a bone/implant construct.

Identification of fractures from computerized Medicare files

Study of non-hip fractures, which are a serious public health problem for persons greater than or equal to 65 years of age, has been hindered by the absence of an economical method for case identification. We assessed the utility of computerized Medicare inpatient, emergency room, hospital outpatient department and physician claims for identifying fractures in an elderly Tennessee Medicaid population. We used these files for 1987 to identify 3086 possible fractures and reviewed medical records for a sample of 1440. Using this sample, we developed a definition of probable fractures that excluded claims unlikely to represent newly diagnosed fractures. For all fractures, this definition had a positive predictive value of 94%, which for individual fracture sites, ranged from 79% (tibia/fibula) to 98% (hip). Of fractures in the reviewed sample, 91% were identified as probable fractures; this upper bound for sensitivity varied between 75% (femoral shaft) and 100% (patella). These data suggest that computerized Medicare files can be used for rapid and economical fracture ascertainment among persons greater than or equal to 65 years of age. However, further work is needed to obtain better estimates of sensitivity.