Bisphosphonates in Total Joint Arthroplasty: A Review of Their Use and Complications

Peri-operative zoledronic acid attenuates peri-prosthetic osteolysis in a rat model of cemented knee replacement

Progressive osteolysis can occur at the cement-bone interface of joint replacements and the associated loss of fixation can lead to clinical loosening. We previously developed a rat hemiarthroplasty model that exhibited progressive loss of fixation with the development of cement-bone gaps under the tibial tray that mimicked patterns found in human arthroplasty retrievals. Here we explored the ability of a bisphosphonate (zoledronic acid, ZA) to attenuate cement-bone osteolysis and maintain implant stability. Sprague-Dawley rats (n = 59) received a poly(methylmethacrylate) cemented tibial component and were followed for up to 12 weeks. Treatment groups included peri-operative administration of ZA (ZA group), administration of ZA at 6 weeks postop (late ZA group), or vehicle (Veh group). There was a 60% reduction in the rate of cement-bone gap formation for the ZA group (0.15 mm3/week) compared to Veh group (0.38 mm3/week, p = 0.016). Late ZA prevented further progression of gap formation but did not reverse bone loss to the level achieved in the ZA group. Micromotion from five times body weight toggle loading was positively correlated with cement-bone gap volume (p = 0.009) and negatively correlated with the amount of cement in the metaphysis (p = 0.005). Reduced new bone formation and enduring nonviable bone in the epiphysis for the ZA group were found. This suggests that low bone turnover in the epiphysis may suppress the early catabolic response due to implantation, thereby maintaining better fixation in the epiphysis. This preclinical model presents compelling supporting data documenting improved maintenance of the cement-bone fixation with the use of peri-operative bisphosphonates.

Does Preoperative Bisphosphonate Use Impact the Risk of Periprosthetic Fracture Following Total Hip Arthroplasty?

INTRODUCTION

Bisphosphonate (BP) use is not uncommon among total hip arthroplasty (THA) candidates. While the impact of BP therapy post-THA has been investigated, there is a paucity of literature discussing the impact of BP therapy pre-THA. Using a national dataset, we aimed to study the association between preoperative BP use and surgical outcomes in primary THA recipients.

METHODS

This retrospective cohort study utilized a commercial claims and Medicare Supplemental Databases to identify adults aged ≥ 18 who had an index non-fracture-related primary THA from 2016 to 2020. The use of BP was defined as ≥ 6 months of BP therapy in the year prior to THA. Outcomes were 90-day all-cause readmission, 90-day readmission related to periprosthetic fracture (PPF), 90-day and 1-year all-cause revision, 1-year PPF-related revision, and 1-year diagnosis of PPF. In a 1:5 propensity-score matched analysis, each THA patient who had preoperative BP use was matched to five THA patients who did not have preoperative BP use. Logistic regression models were fitted; we report odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

Of 91,907 THA patients, 1,018 (1.1%) used BP preoperatively. In the propensity-score-matched cohort (1,018 preoperative BP users, 5,090 controls), preoperative BP use was significantly associated with increased odds of 90-day all-cause revision surgery (OR 1.67; 95% CI 1.10 to 2.53; P = 0.02), 1-year PPF-related revision (OR 2.23; 95% CI 1.21 to 4.10; P = 0.01), and 1-year PPF diagnosis (OR 1.88; 95% CI 1.10 to 3.20; P = 0.02). There was no significant association between preoperative BP use and the other outcomes in the matched cohort.

CONCLUSION

These findings suggest that preoperative BP use is associated with an increased risk of revision surgery and PPF in both the short and long term. This information can help in preoperative planning and patient counseling, potentially leading to improved surgical outcomes and reduced complication rates.

Chronic Oral Corticosteroid Use and 10-Year Incidence of Major Complications Following Total Knee Arthroplasty

BACKGROUND

Oral corticosteroids are the primary treatment for several autoimmune conditions. The risk of long-term implant, bone health, and infectious-related complications in patients taking chronic oral corticosteroids before total knee arthroplasty (TKA) is unknown. We compared the 10-year cumulative incidence of revision, periprosthetic joint infection (PJI), fragility fracture (FF), and periprosthetic fracture following TKA in patients who had and did not have preoperative chronic oral corticosteroid use.

METHODS

A retrospective cohort analysis was conducted using a national database. Primary TKA patients who had chronic preoperative oral corticosteroid use were identified using Current Procedural Terminology and International Classification of Disease 9 and 10 codes. Exclusion criteria included malignancy, osteoporosis treatment, trauma, and < 2-year follow-up. Primary outcomes were 10-year cumulative incidence and hazard ratios (HRs) of all-cause revision (ACR), aseptic revision, PJI, FF, and periprosthetic fracture. A Kaplan-Meier analysis and a multivariable Cox proportional hazards model were utilized. Overall, 611,596 patients were identified, and 5,217 (0.85%) were prescribed chronic corticosteroids. There were 10,000 control patients randomly sampled for analysis.

RESULTS

Corticosteroid patients had significantly higher 10-year HR of FF (HR; 95% confidence interval); P value (1.47; 1.34 to 1.62; P < .001)], ACR (1.21; 1.05 to 1.40; P = .009), and PJI (1.30; 1.01 to 1.69; P = .045) when compared to the control.

CONCLUSIONS

Patients prescribed preoperative chronic oral corticosteroids had higher risks of ACR, PJI, and FF within 10 years following TKA compared to patients not taking corticosteroids. This information can be used by surgeons during preoperative counseling to educate this high-risk patient population about their increased risk of postoperative complications.

Periprosthetic fractures are osteoporotic fractures: missed opportunities for osteoporosis diagnosis

Joint replacement surgery is common in older adults, leading to increasing periprosthetic fracture (PPFx) occurrence. We reviewed all PPFx seen over a 4-year period at an academic hospital. Clinical osteoporosis could be diagnosed based on existing data in 104 (67%) at the time of PPFx. Periprosthetic fractures are generally osteoporosis-related.

PURPOSE

Periprosthetic fractures (PPFx) cause morbidity, mortality, and cost. This study's purpose was to describe osteoporosis-related data available at the time of PPFx.

METHODS

The electronic medical record (EMR) of PPFx patients seen over 4 years in a university orthopedic practice were reviewed. Demographic data and osteoporosis relevant parameters were collected. Prior DXA studies were reviewed, and L1 Hounsfield unit (HU) measurements were performed on CT scans obtained within 2 years before PPFx. Clinical osteoporosis was defined as prior diagnosis, prescribed osteoporosis treatment, T-score ≤  - 2.5, HU ≤ 100, or prior fracture.

RESULTS

Records of 156 PPFx patients (115 F/41 M), mean (SD) age 75.4 (11.9), were reviewed. Almost all 153/156 (98%) of these fractures were femoral. Falls caused 139 (89%); 12 (8%) were spontaneous. Mean time post-arthroplasty was 7.9 (6.3) years. Prior fragility fracture(s) occurred in 72 (46%); 14 were PPFx. Osteoporosis was previously diagnosed in 45 (29%) and medications prescribed in 41 (26%). Prior to PPFx, DXA data were available in 62, mean (SD) lowest T-score was - 1.9 (0.9) and was ≤  - 2.5 in 19. CT data were available in 46; mean (SD) L1 HU was 79.0 (29.4) and was ≤ 100 in 35. Based on existing data, clinical osteoporosis could have been diagnosed in 104 (67%) at the time of PPFx.

CONCLUSION

Periprosthetic fractures are osteoporosis-related. They occur in older adults, often female, and result from falls; BMD, when assessed, is low. Data available at the time of PPFx often allows osteoporosis diagnosis; this should prompt evaluation and pharmacologic treatment consideration.

Initiation of Bisphosphonates Prior to Total Joint Arthroplasty Does Not Lower Periprosthetic Fracture Risk

BACKGROUND

Many patients are diagnosed with osteoporosis shortly prior to scheduling total joint arthroplasty (TJA). The purpose of this study was to determine if initiation of bisphosphonates prior to TJA decreased the risks of periprosthetic fractures (PPFx).

METHODS

A national database was used to identify all patients diagnosed with osteoporosis prior to primary TJA. Patients who had osteoporosis without preoperative bisphosphonate use were designated as our control group. Patients on preoperative bisphosphonates were stratified based on duration and timing of bisphosphonate use: long-term preoperative users (initiation 3 to 5 years preoperatively), intermediate-term preoperative users (initiation 1 to 3 years preoperatively), and short-term preoperative users (initiation 0 to 1 year preoperatively). Rates of PPFx at 90-day and 2-year follow-up were compared between groups.

RESULTS

In patients undergoing primary total hip arthroplasty, there was no difference in PPFx rate between our control group and preoperative bisphosphonate users of all durations at 90-day (P = .12) and 2-year follow-up (P = .22). In patients undergoing primary total knee arthroplasty, there was no difference in PPFx rate between our control group and preoperative bisphosphonate users of all durations at 90-day (P = .76) and 2-year follow-up (P = .39).

CONCLUSIONS

In patients undergoing primary TJA, preoperative bisphosphonate users did not have a decreased PPFx rate compared to our control group at 90-day and 2-year follow-up. Our findings suggest that preoperative bisphosphonate use, regardless of the duration of treatment, does not confer protective benefits against PPFx in patients undergoing TJA.

LEVEL OF EVIDENCE

Prognostic Level III.

Osteoarthritis: Insights into Diagnosis, Pathophysiology, Therapeutic Avenues, and the Potential of Natural Extracts

Osteoarthritis (OA) stands as a prevalent and progressively debilitating clinical condition globally, impacting joint structures and leading to their gradual deterioration through inflammatory mechanisms. While both non-modifiable and modifiable factors contribute to its onset, numerous aspects of OA pathophysiology remain elusive despite considerable research strides. Presently, diagnosis heavily relies on clinician expertise and meticulous differential diagnosis to exclude other joint-affecting conditions. Therapeutic approaches for OA predominantly focus on patient education for self-management alongside tailored exercise regimens, often complemented by various pharmacological interventions primarily targeting pain alleviation. However, pharmacological treatments typically exhibit short-term efficacy and local and/or systemic side effects, with prosthetic surgery being the ultimate resolution in severe cases. Thus, exploring the potential integration or substitution of conventional drug therapies with natural compounds and extracts emerges as a promising frontier in enhancing OA management. These alternatives offer improved safety profiles and possess the potential to target specific dysregulated pathways implicated in OA pathogenesis, thereby presenting a holistic approach to address the condition's complexities.

Bisphosphonate Use May be Associated With an Increased Risk of Periprosthetic Hip Fracture

BACKGROUND

Osteoporosis is common among patients undergoing primary total hip arthroplasty (THA). This study aimed to evaluate the effect of bisphosphonate treatment on osteoporotic patients undergoing primary THA.

METHODS

Using a national database, 30,137 patients who had osteoporosis before primary elective THA were identified during 2010 to 2020. Patients undergoing nonelective THA and those using corticosteroids or other medications for osteoporosis were excluded. Bisphosphonate users and bisphosphonate naïve patients were matched 1:1 based on age, sex, Elixhauser comorbidity index, and a history of obesity, rheumatoid arthritis, tobacco use, and alcohol abuse. Kaplan-Meier and multivariate analyses were used to compare 2-year outcomes between groups.

RESULTS

Among matched cohorts of 9,844 patients undergoing primary THA, bisphosphonate use was associated with a significantly higher 2-year rate of periprosthetic fracture (odds ratio 1.29, 95% confidence interval 1.04 to 1.61, P = .022). There was a trend toward increased risk of any revision with bisphosphonate use (odds ratio 1.19, confidence interval 1.00 to 1.41, P = .056). Rates of infection, aseptic loosening, dislocation, and mortality were not statistically different between bisphosphonate users and bisphosphonate-naïve patients.

CONCLUSION

In osteoporotic patients, bisphosphonate use before primary THA is an independent risk factor for periprosthetic fracture. Additional longer-term data are needed to determine the underlying mechanism for this association and identify preventative measures.

The Effect of Preoperative Bisphosphonate Use on Total Hip Arthroplasty Outcomes

BACKGROUND

Patients undergoing total hip arthroplasty (THA) commonly have osteoporosis for which bisphosphonates (BPs) are Food and Drug Administration (FDA)-approved for treatment. Bisphosphonate use post-THA is associated with decreased periprosthetic bone loss or revisions, and increased longevity of implants. However, evidence is lacking for preoperative bisphosphonate use in THA recipients. This study investigated the association between bisphosphonate use pre-THA and outcomes.

METHODS

A retrospective review of a national administrative claims database was conducted. Among THA recipients who had a prior diagnosis of hip osteoarthritis and osteoporosis/osteopenia, the treatment group (BP-exposed) consisted of patients who had a history of bisphosphonate use at least 1 year before THA; controls (BP-naive) comprised patients who did not have preoperative bisphosphonate use. The BP-exposed were matched to BP-naive in a 1:4 ratio by age, sex, and comorbidities. Logistic regressions were used to calculate the odds ratio for intraoperative and 1-year postoperative complications.

RESULTS

The BP-exposed group had significantly higher rates of intraoperative and 1-year postoperative periprosthetic fractures (odds ratio (OR): 1.39, 95% confidence interval (CI): 1.23, 1.57) and revisions (OR: 1.14, 95% CI: 1.04, 1.25) compared with the BP-naive controls. BP-exposed also experienced higher rates of aseptic loosening, dislocation, periprosthetic osteolysis, and stress fracture of the femur or hip/pelvis compared to the BP-naive controls, but these values were not statistically significant.

CONCLUSION

The use of bisphosphonates in THA patients preoperatively is associated with higher rates of intraoperative and 1-year postoperative complications. These findings may impact the management of patients undergoing THA who have a prior diagnosis of osteoporosis/osteopenia and use of bisphosphonates.

LEVEL OF EVIDENCE

Retrospective Cohort Study (Level 3).

Rehabilitation: Neurogenic Bone Loss after Spinal Cord Injury

Osteoporosis is a common skeletal disorder which can severely limit one's ability to complete daily tasks due to the increased risk of bone fractures, reducing quality of life. Spinal cord injury (SCI) can also result in osteoporosis and sarcopenia. Most individuals experience sarcopenia and osteoporosis due to advancing age; however, individuals with SCI experience more rapid and debilitating levels of muscle and bone loss due to neurogenic factors, musculoskeletal disuse, and cellular/molecular events. Thus, preserving and maintaining bone mass after SCI is crucial to decreasing the risk of fragility and fracture in vulnerable SCI populations. Recent studies have provided an improved understanding of the pathophysiology and risk factors related to musculoskeletal loss after SCI. Pharmacological and non-pharmacological therapies have also provided for the reduction in or elimination of neurogenic bone loss after SCI. This review article will discuss the pathophysiology and risk factors of muscle and bone loss after SCI, including the mechanisms that may lead to muscle and bone loss after SCI. This review will also focus on current and future pharmacological and non-pharmacological therapies for reducing or eliminating neurogenic bone loss following SCI.

Advanced Procedure of Simultaneous Electrodeposition from a Natural Deep Eutectic Solvent of a Drug and a Polymer Used to Improve TiZr Alloy Behavior

This paper presents research about the embedding and release of gentamicin from an electrochemical deposition of polypyrrole from ionic liquids such as choline chloride on TiZr bioalloy. The electrodeposited films were morphologically investigated using scanning electron microscopy (SEM) with an EDX module, and polypyrrole and gentamicin were both identified using structural FT-IR analysis. The film's characterization was completed with an evaluation of hydrophilic-hydrophobic balance, with electrochemical stability measurements in PBS and with antibacterial inhibition. A decrease in the value of the contact angle was observed from 47.06° in the case of the uncoated sample to 8.63° in the case of the sample covered with PPy and GS. Additionally, an improvement in the anticorrosive properties of the coating was observed by increasing the efficiency to 87.23% in the case of TiZr-PPy-GS. A kinetic study of drug release was performed as well. The drug molecule might be provided by the PPy-GS coatings for up to 144 h. The highest amount released was calculated to be 90% of the entire drug reservoir capacity, demonstrating the effectiveness of the coatings. A non-Fickian behavior was established as a mechanism for the release profiles of the gentamicin from the polymer layer.

Hormone replacement therapy does not increase thrombosis risk following THA: a national database study

PURPOSE

Hormone replacement therapy (HRT) causes a significant increase in the risk of venous thrombosis. The risk of medical and surgery-related complications among women taking HRT following total hip arthroplasty (THA) is poorly understood, and there are currently no guidelines in place regarding venous thromboembolism prophylaxis in this patient population. The purpose of this study was to evaluate the frequency of early medical and surgery-related complications following THA among women taking HRT.

METHODS

Women aged > 40 years of age who underwent primary THA were identified from a retrospective database review. A control group of non-HRT users was matched using propensity scoring to HRT users. Rates of 90-day medical complications and 1-year surgery-related complications were compared between cohorts using odds ratios. Postoperative anticoagulation regimens were also compared.

RESULTS

There were 3,936 patients in the HRT cohort who were matched to 39,360 patients not taking HRT. There were no significant differences in rates of DVT (OR 0.94, p = 0.6601) or PE (OR 0.80, p = 0.4102) between cohorts. Patients on HRT were more likely to sustain a dislocation (OR 1.35, p = 0.0269) or undergo revision surgery (OR 1.23, p = 0.0105). HRT patients were more likely to be prescribed warfarin (OR 1.21, p = 0.0001) or enoxaparin (OR 1.18, p = 0.0022) and less likely to be prescribed rivaroxaban (OR 0.62, p < 0.0001) compared to controls.

CONCLUSIONS

HRT was not found to be an independent risk factor for thromboembolism following THA. Further research is warranted to better delineate the ideal perioperative medical management of HRT users undergoing THA.

The histological assessment of new bone formation with zolendronic acid loaded bone allograft in rabbit femoral bone defect

The aim of this experimental study was to evaluate the effect of zolendronic acid (ZOL) combined with bone allograft prepared using the Marburg Bone Bank System on bone formation in the implant remodeling zone. Femoral bone defects with a diameter of 5 mm and a depth of 10 mm were created in 32 rabbits. Animals were divided into 2 similar groups: Group 1 (control), where defects were filled with bone allograft, and Group 2, where allograft was combined with ZOL. Eight animals from each group were sacrificed at 14- and 60-days post-surgery and bone defect healing was assessed using histopathological and histomorphometric analyses after 14 and 60 days. The results showed that new bone formation within the bone allograft was significantly greater in the control group than in the ZOL-treated group after 14 and 60 days (p<0.05). In conclusion, local co-administration of ZOL on heat-treated allograft inhibits allograft resorption and new bone formation in the bone defect.

Periprosthetic fractures: an unrecognized osteoporosis crisis

Total joint replacement is common and increasing. Many of these patients have low bone mineral density preoperatively, and arthroplasty leads to bone loss. As falls are common before and after arthroplasty, it is unsurprising that periprosthetic fractures, defined as those associated with an orthopedic device, whether a joint replacement or other internal fixation devices, are not rare. These fractures engender morbidity and mortality comparable to osteoporosis-related hip fractures but remain largely unrecognized and untreated by osteoporosis/metabolic bone disease clinicians. Indeed, recent osteoporosis guidelines are silent regarding periprosthetic fractures. The purposes of this clinical review are to briefly describe the epidemiology of arthroplasty procedures and periprosthetic fractures, raise awareness that these fractures are osteoporosis-related, and suggest approaches likely to reduce their occurrence. Notably, bone health evaluation is essential following the occurrence of a periprosthetic fracture to reduce subsequent fracture risk. Importantly, in addition to such secondary fracture prevention, primary prevention, i.e., bone health assessment and optimization prior to elective orthopedic procedures, is appropriate.

Recent Advancements in Metallic Drug-Eluting Implants

Over the past decade, metallic drug-eluting implants have gained significance in orthopedic and dental applications for controlled drug release, specifically for preventing infection associated with implants. Recent studies showed that metallic implants loaded with drugs were substituted for conventional bare metal implants to achieve sustained and controlled drug release, resulting in a desired local therapeutic concentration. A number of secondary features can be provided by the incorporated active molecules, including the promotion of osteoconduction and angiogenesis, the inhibition of bacterial invasion, and the modulation of host body reaction. This paper reviews recent trends in the development of the metallic drug-eluting implants with various drug delivery systems in the past three years. There are various types of drug-eluting implants that have been developed to meet this purpose, depending on the drug or agents that have been loaded on them. These include anti-inflammatory drugs, antibiotics agents, growth factors, and anti-resorptive drugs.

The Role of the Innate Immune System in Wear Debris-Induced Inflammatory Peri-Implant Osteolysis in Total Joint Arthroplasty

Periprosthetic osteolysis remains a leading complication of total hip and knee arthroplasty, often resulting in aseptic loosening of the implant and necessitating revision surgery. Wear-induced particulate debris is the main cause initiating this destructive process. The purpose of this article is to review recent advances in understanding of how wear debris causes osteolysis, and emergent strategies for the avoidance and treatment of this disease. A strong activator of the peri-implant innate immune this debris-induced inflammatory cascade is dictated by macrophage secretion of TNF-α, IL-1, IL-6, and IL-8, and PGE2, leading to peri-implant bone resorption through activation of osteoclasts and inhibition of osteoblasts through several mechanisms, including the RANK/RANKL/OPG pathway. Therapeutic agents against proinflammatory mediators, such as those targeting tumor necrosis factor (TNF), osteoclasts, and sclerostin, have shown promise in reducing peri-implant osteolysis in vitro and in vivo; however, radiographic changes and clinical diagnosis often lag considerably behind the initiation of osteolysis, making timely treatment difficult. Considerable efforts are underway to develop such diagnostic tools, therapies, and identify novel targets for therapeutic intervention.