Perioperative Periprosthetic Femur Fractures are Strongly Correlated With Fixation Method: an Analysis From the American Joint Replacement Registry

Bone mineral density assessment by DXA in rheumatic patients with end-stage osteoarthritis undergoing total joint arthroplasty

BACKGROUND

Patients with rheumatic diseases have a high risk for joint destruction and secondary osteoarthritis (OA) as well as low bone mineral density (BMD, i.e., osteoporosis). While several factors may lead to low BMD in these patients, the value of BMD measurements in rheumatic patients with end-stage OA scheduled for total joint arthroplasty is unknown.

METHODS

In this retrospective cross-sectional study of 50 adults with secondary OA due to rheumatic diseases, we evaluated dual energy X-ray absorptiometry (DXA) measurements of both hips and the spine performed within 3 months prior to arthroplasty (n = 25 total hip arthroplasty, THA; n = 25 total knee arthroplasty, TKA). We analyzed various demographic and disease-specific characteristics and their effect on DXA results by using group comparisons and multivariate linear regression models.

RESULTS

Although patients undergoing TKA were younger (63.2 ± 14.2 vs. 71.0 ± 10.8 yr., p = 0.035), osteoporosis was observed more frequently in patients scheduled for TKA than THA (32% vs. 12%). Osteopenia was detected in 13/25 patients (52%) in both the THA and TKA cohort. In the THA cohort, female sex, lower BMI and prednisolone use were associated with lower T-score in the hip. In TKA patients, higher OA grade determined by Kellgren-Lawrence score was associated with lower T-score in the hip of the affected side.

CONCLUSIONS

Osteoporosis is present in a considerable frequency of rheumatic patients with end-stage OA, and THA and TKA patients show distinct frequencies and risk factors of low BMD. Our findings point to a potential value of DXA regarding preoperative evaluation of bone status.

Biomechanics of a cemented short stem: a comparative in vitro study regarding primary stability and maximum fracture load

PURPOSE

In total hip arthroplasty, uncemented short stems have been used more and more frequently in recent years. Especially for short and curved femoral implants, bone-preserving and soft tissue-sparing properties are postulated. However, indication is limited to sufficient bone quality. At present, there are no curved short stems available which are based on cemented fixation.

METHODS

In this in vitro study, primary stability and maximum fracture load of a newly developed cemented short-stem implant was evaluated in comparison to an already well-established cemented conventional straight stem using six pairs of human cadaver femurs with minor bone quality. Primary stability, including reversible micromotion and irreversible migration, was assessed in a dynamic material-testing machine. Furthermore, a subsequent load-to-failure test revealed the periprosthetic fracture characteristics.

RESULTS

Reversible and irreversible micromotions showed no statistical difference between the two investigated stems. All short stems fractured under maximum load according to Vancouver type B3, whereas 4 out of 6 conventional stems suffered a periprosthetic fracture according to Vancouver type C. Mean fracture load of the short stems was 3062 N versus 3160 N for the conventional stems (p = 0.84).

CONCLUSION

Primary stability of the cemented short stem was not negatively influenced compared to the cemented conventional stem and no significant difference in fracture load was observed. However, a clear difference in the fracture pattern has been identified.

Multi-Site Insufficiency Pelvic Fracture Following Total Hip Arthroplasty

Patient: Female, 47-year-old

Final Diagnosis: Pelvic fracture

Symptoms: Hip pain

Medication: —

Clinical Procedure: —

Specialty: Orthopedics and Traumatology

Mortality as a competition risk factor in the survival analysis of the results of the type of fixation of the total hip prosthesis in octogenarian patients

INTRODUCTION

Total hip replacement (THR) is challenging in octogenarians due to associated comorbidities and controversy regarding fixation type. We ask whether cemented THR is superior to uncemented THR in patients above the age of 80 years.

MATERIAL AND METHODS

A total of 382 patients (441 hips) aged 80 years or older who underwent THR between 2004 and 2015 were analysed. A cemented THR was implanted in 196 hips (group 1), an uncemented THR with a grit-blasted stem in 121 (group 2), or with a porous-coated stem in 124 (group 3). Patients in group 1 had a higher mean age, more comorbidities and osteoporotic bone. Survival analysis was calculated using cumulative incidence function to account for the competing risk of death.

RESULTS

Medical complications rate was similar. There were 3post-operative fractures: one in group 2 and 2in group 3. Competing risk analysis showed that the cumulative incidence of revision for any cause was 2.3 in group 1, 6.0 in group 2 and 4.1 in group 3 at 10years, and the cumulative incidence of revision for aseptic loosening was 1.2 in group 1, 3.7 in group 2 and 0 in group 3 at the same period.

CONCLUSIONS

THR presents an acceptable number of adverse events for octogenarian patients. Despite uncemented fixation was satisfactory, the higher peri-prosthetic fracture rate worsens results in this group.

A Calcar Collar Is Protective Against Early Torsional/Spiral Periprosthetic Femoral Fracture: A Paired Cadaveric Biomechanical Analysis

BACKGROUND

Periprosthetic fracture is a leading reason for readmission following total hip arthroplasty. Most of these fractures occur during the early postoperative period before bone ingrowth. Before ingrowth occurs, the femoral component can rotate relative to the femoral canal, causing a spiral fracture pattern. We sought to evaluate, in a paired cadaver model, whether the torsional load to fracture was higher in collared stems. The hypothesis was that collared stems have greater load to fracture under axial and torsional loads compared with collarless stems.

METHODS

Twenty-two cadaveric femora (11 matched pairs) with a mean age of 77 ± 10.2 years (range, 54 to 90 years) were harvested. Following dissection, the femora were evaluated with use of a dual x-ray absorptiometry scanner and T scores were recorded. We utilized a common stem that is available with the same intraosseous geometry with and without a collar. For each pair, 1 femur was implanted with a collared stem and the contralateral femur was implanted with a collarless stem with use of a standard broaching technique. A compressive 68-kg load was applied to simulate body weight during ambulation. A rotational displacement was then applied until fracture occurred. Peak torque prior to fracture was measured with use of a torque meter load cell and data acquisition software.

RESULTS

The median torque to fracture was 65.4 Nm for collared stems and 43.1 Nm for uncollared stems (p = 0.0014, Wilcoxon signed-rank test). The median T score was -1.95 (range, -4.1 to -0.15). The median difference in torque to fracture was 29.18 Nm. As expected in each case, the mode of failure was a spiral fracture around the implant.

CONCLUSIONS

Collared stems seemed to offer a protective effect in torsional loading in this biomechanical model comparing matched femora.

CLINICAL RELEVANCE

These results may translate into a protective effect against early periprosthetic Vancouver B2 femoral fractures that occur before osseous integration has occurred.

Demographics, Treatment, and Cost of Periprosthetic Femur Fractures: Fixation Versus Revision

Introduction:

Periprosthetic femur fractures (PPFX) are complications of both total hip and knee arthroplasty and may be treated with open reduction and internal fixation (ORIF) or revision arthroplasty. Differences in treatment and fracture location may be related to patient demographics and lead to differences in cost. Our study examined the effects of demographics and treatment of knee and hip PPFXs on length of stay (LOS) and cost.

Methods:

Of all, 932 patients were identified with hip or knee PPFXs in the National Inpatient Sample from January 2013 to September 2015. Age, gender, race, mortality, comorbidity level, LOS, total cost, procedure type, geographic region, and hospital type were recorded. A generalized linear regression model was conducted to analyze the effect of fracture type on LOS and cost.

Results:

Differences in gender (66% vs 83.7% female, P < .01), comorbidities (fewer in hips, P < .01), and costs (US$30 979 vs US$27 944, P < .01) were found between the hip and knee groups. Knees had significantly higher rates of ORIF treatment (80.7% vs 39.1%) and lower rates of revision arthroplasties (19.3% vs 60.9%) than hip PPFXs (P < .01). Within both groups, patients with more comorbidities, revision surgery, and blood transfusions were more likely to have a longer LOS and higher cost.

Conclusion:

Periprosthetic femur fractures patients are not homogenous and treatment varies between hip and knee locations. For knee patients, those treated with ORIF were younger, with fewer comorbidities than those treated with revision. Conversely, hip patients treated with ORIF were older, with more comorbidities than those treated with revision. Hips had higher costs than knees, and cost correlated with revision arthroplasty and more comorbidities. In both hip and knee groups, longer LOS was associated with more comorbidities and being treated in urban teaching hospitals. Total cost had the strongest associations with revision procedures as well as number of comorbidities and blood product use.

Three dimensional bone mineral density changes in the femur over 1 year in primary total hip arthroplasty patients

BACKGROUND

The aim of the study was to compare the bone mineral density changes between unmatched patients undergoing total hip arthroplasty receiving uncemented and cemented type of implants. Previous studies have used DEXA or a two dimensional analysis to estimate the bone quality following total joint replacement, whereas this study presents the changes in three dimensions.

METHODS

Fifty subjects both male and females receiving both cemented and uncemented type of implant were recruited. Two CT scans were taken of each subject, the first at 24 h post surgery and the second one 1 year after surgery. The scans were calibrated using a phantom converting the Hounsfield units to bone mineral density values in g/cm³. The two scans were registered together using anatomical landmarks and resliced to compare the two femurs in the identical frame of reference. The bone density gain and loss was calculated by comparing density values between the two sets of scans.

FINDINGS

The results showed that most of the bone loss was located around the Lesser Trochanter and some bone density gain at the distal tip of the implant. The three dimensional density changes occur differently between individuals and the study showed no correlation of bone loss with age.

INTERPRETATION

The bone loss occurred mostly at the proximal femur, which is in agreement with previously presented studies. By carrying out three dimensional analysis on the bone gain and loss on the femur, it is possible to identify the patients that are showing high degree of bone loss.

The Use of Cement in Hip Arthroplasty: A Contemporary Perspective

Notable advances in hip arthroplasty implants and techniques over the past 60 years have yielded excellent survivorship of fully cemented, hybrid, and reverse hybrid total hip replacements as demonstrated in joint registries worldwide. Major advances in noncemented implants have reduced the use of cement, particularly in North America. Noncemented implants predominate today based on procedural efficiency, concern related to thromboembolic risk, and a historic belief that cement was the primary cause of osteolysis and implant loosening. With the decline of cemented techniques, press-fit fixation has become common even in osteoporotic elderly patients. Unfortunately, there is a troubling rise in intraoperative, as well as early and late postoperative periprosthetic fractures associated with the use of noncemented implants. Despite the success of noncemented fixation, an understanding of modern cement techniques and cemented implant designs is useful to mitigate the risk of periprosthetic fractures. Cemented acetabular components can be considered in elderly patients with osteoporotic or pathologic bone. Cemented stems should be considered with abnormal proximal femoral morphology, conversion of failed hip fixation, inflammatory arthritis, patient age over 75 (especially women), osteoporotic bone (Dorr C), and in the treatment of femoral neck fractures.

Cemented versus uncemented total knee arthroplasty in younger patients: A protocol of retrospective cohort trial

BACKGROUND

Recently, controversy still exists regarding the clinical effects of cemented or cementless technique in young patients in total knee arthroplasty (TKA). In this context, the present study aimed to determine the functional outcomes and clinical reliability of cementless components versus those of conventional cemented components for young patients in primary TKA.

METHODS

A retrospective review of primary TKAs performed with cementless or cemented fixation between May 2010 and February 2019 was conducted with Institutional Review Board approval. All cases were performed by a single surgeon. Institutional review board approval was obtained prior to conducting chart review and analysis. The primary outcome compared between the 2 fixation groups was the rate of postoperative complications and revision related to TKA, occurring at any point in follow-up. Secondary outcome measures included surgical time, Oxford Knee Score, range of motion, and radiographic outcomes such as progressive radiolucent lines, osteolysis, or component migration.

RESULTS

We were able to directly compare the outcomes of cemented versus cementless techniques and might reveal a better technique in TKA.

TRIAL REGISTRATION

This study protocol was registered in Research Registry (researchregistry5459).

On-Table and Short-Term Mortality: A Single-Institution Experience With Cementing All Hip Arthroplasties for Neck of Femur Fractures

BACKGROUND

To review on-table, day 0, day 1, day 7, and day 30 mortality after hemiarthroplasty or total hip arthroplasty (THA) using cemented femoral stems for femoral neck fractures in order to evaluate risk factors for perioperative and short-term mortality.

METHODS

The medical records of 751 consecutive cases with neck of femur fractures who underwent hemiarthroplasty (n = 602) or THA (n = 149) with cemented stems between January 2011 and December 2016 were retrospectively reviewed from a prospectively gathered database. The primary outcome measures were on-table, day 0, day 1, day 7, and day 30 mortality. Univariate and multivariate analyses were performed in order to identify various contributing patient and surgical variables.

RESULTS

There were 2 on-table deaths (0.27%): one patient had a cardiorespiratory arrest at the time of inserting the femoral stem and the other had a cardiorespiratory arrest at the end of wound closure some 20 minutes after cementing. There were 3 further day 0 deaths meaning the day 0 mortality rate was 0.67% (5/751). All 5 patients were older than 80 years and had an American Society of Anesthesiologists grade 3 or more. The 1-day, 7-day, and 30-day mortality rates were 0.93% (7 patients), 2.7% (20 patients), and 6.8% (51 patients), respectively. There is significantly higher 30-day mortality risk associated with increasing American Society of Anesthesiologists grade (P < .001) when adjusted for age, gender, and type of surgery (hemiarthroplasty compared with THA).

CONCLUSION

In our neck of femur fracture patients who were operated with cemented stems, 7-day and 30-day mortality rates were 2.7% and 6.8%, respectively. Cemented stems should be used with caution in elderly hip fracture patients with multiple comorbidities who are at high risk of perioperative mortality.

Risk Factors for Periprosthetic Femur Fracture and Influence of Femoral Fixation Using the Mini-Anterolateral Approach in Primary Total Hip Arthroplasty

BACKGROUND

The mini-anterolateral (AL) approach for total hip arthroplasty (THA) has gained popularity. In contrast to other approaches, risk factors for periprosthetic femur fractures have not been well established for the AL approach.

METHODS

Six hundred eighty-four primary THAs performed using the AL approach were retrospectively reviewed for risk factors associated with perioperative periprosthetic femur fractures within 3 months of surgery. Risk factors evaluated were gender, age, body mass index, laterality, and Dorr ratio of the proximal femur. Cemented stems and collared uncemented stems were compared to uncemented tapered-wedge and meta-diaphyseal stems. A Student's t-test was used for continuous variables, and a chi-squared test was used for categorical variables.

RESULTS

Of 684 primary THAs performed, 57 (8.3%) resulted in fracture. Twenty-eight (4.1%) occurred intraoperatively and 29 (4.2%) occurred postoperatively within 90 days. All intraoperative fractures were fixed at the time of surgery and healed uneventfully. Of the postoperative fractures, 15 (2.2%) were amenable to nonoperative management and healed. Fourteen (2.0%) required revision arthroplasty. There was a significantly lower rate of fracture in patients receiving cemented or collared stems (0%, n = 101) than in those receiving tapered-wedge or meta-diaphyseal fitting stems (9.8%, n = 583; P = .0009). Odds of fracture increased with female gender (P = .0063) and increasing Dorr ratio (P = .0003). Analysis showed a trend toward increased risk with older age, but did not achieve statistical significance. Body mass index and laterality showed no statistically significant effect.

CONCLUSION

Performing primary THA via the AL approach, 2.0% of patients had a postoperative fracture requiring revision within the first 3 months. With cemented and collared stems, the fracture rate was significantly lower. Surgeons should consider using cemented or collared stems in high-risk patients.

Bone Loss Following Cementless Hemiarthroplasty for the Treatment of Femoral Neck Fracture

BACKGROUND

With the advances in medicine, an increasing number of the ageing population are a public health concern in terms of age-related complications. Among them, displaced neck fractures often require surgical intervention or arthroplasty to achieve the mobilization of the elderly and good life quality. The aim of the study is to monitor the changes in bone mineral density (BMD) around the femoral stem and the effects on functional outcomes in patients treated with cementless hemiarthroplasty following femoral neck fracture.

MATERIALS AND METHODS

Seventy-one patients aged 70 years or older who were treated with cementless hemiarthroplasty for a displaced femoral neck fracture were prospectively followed for 2 years. The percent change in the periprosthetic BMD in each Gruen zone was compared to the baseline using dual-energy X-ray absorptiometry (DEXA). Demographic factors [age, body mass index (BMI), and sex] that could possibly influence BMD and the clinical outcome were evaluated.

RESULTS

Fifty-one patients were available for the final follow-up. The mean age was 76.5 (range 70-89) years. The mean BMI was 28.9 (range 22.7-37.2). The mean Harris hip score at the final follow-up was 84.3 (range 72-93). There was a significant decrease in BMD in all Gruen zones (p < 0.001), except in zone 3 (R3, p = 0.547). The reduction in BMD was highest in the calcar and the greater trochanter region. The femur diaphysis was relatively spared, with zone 3 showing no significant bone mineral loss. The age and BMI of the patients were not correlated with the postoperative change in BMD in any of the Gruen zones. The degree of reduction in bone density was not correlated with the clinical outcome.

CONCLUSIONS

Cementless hemiarthroplasty for the treatment of femoral neck fracture in elderly patients achieves a good clinical outcome despite significant bone loss around the femoral stem. The reduction in BMD is more pronounced in the metaphyseal region.