Defining the shelf-life of calcium sulfate beads embedded with tobramycin and vancomycin

Background

Antibiotic-laden calcium sulfate beads are gaining popularity in the treatment of orthopaedic infections such as fracture-related infection and osteomyelitis. Calcium sulfate beads have several advantages over polymethylmethacrylate (PMMA) beads as they are bioabsorbable, have demonstrated improved elution characteristics, and have lower peak polymerization temperatures than seen in PMMA. The ability to make and store antibiotic beads for later use has the potential to standardize dosing and decrease operating room times and healthcare costs. This study aims to determine the antibiotic efficacy of premade, antibiotic-laden calcium sulfate beads.

Methods

Calcium sulfate beads containing vancomycin or tobramycin were molded to 4.8 mm in diameter and stored for shelf-life durations of three and six months at 20 °C. A subset of beads was tested immediately after creation. At the designated time points, beads were placed into a buffer solution and incubated at 37 °C with agitation. Antibiotic eluent was collected at 1-hour, 4-hour, 24-hour, and 48-hour timepoints. Eluent concentrations were inferred from a prior study implementing the same calcium sulfate bead model. Eluent was used in microbroth dilution assays to determine its minimum inhibitory concentration (MIC) against methicillin-sensitive Staphylococcus aureus.

Results

MIC assays for tobramycin and vancomycin against S. aureus yielded concentrations consistent with previously reported ranges. MIC results across different bead shelf lives also remained consistent without an increase in MIC with increasing shelf life for either antibiotic.

Conclusions

Shelf life up to six months does not impact the efficacy of tobramycin or vancomycin eluent from calcium sulfate beads in vitro compared to beads made and tested immediately. These results provide preliminary evidence that tobramycin and vancomycin retain their antimicrobial activity in calcium sulfate beads for at least six months stored at room temperature. Additional studies on sterilization techniques are necessary prior to considering use of prefabricated antibiotic-loaded calcium sulfate beads in clinical practice.

The State of Local Antibiotic Use in Orthopedic Trauma

Fracture-related infections are a challenging complication in orthopedic trauma that often necessitates multiple surgeries. Early administration of systemic antibiotics and surgical intervention remains the gold standard of care, but despite these measures, treatment failures can be as high as 35%. For these reasons, the introduction of local antibiotics at the site of at-risk fractures has increased over the past decade. This review looks at the various measures being used clinically including local antibiotic powder, polymethylmethacrylate, biodegradable substances, antibiotic-coated implants, and novel methods such as hydrogels and nanoparticles that have the potential for use in the future.

Biofilm and How It Relates to Prosthetic Joint Infection

Prosthetic joint infection following total joint arthroplasty is a devastating complication, resulting in increased morbidity and mortality for the patient. The formation of a biofilm on implanted hardware contributes to the difficulty in successful identification and eradication of the infection. Antibiotic therapy and surgical intervention are necessary for addressing this condition; we present a discussion on different treatment options, including those that are not yet routinely utilized in the clinical setting or are under investigation, to highlight the present and future of PJI management.

Feasibility of using bacteriophage therapy to treat Staphylococcal aureus fracture-related infections

OBJECTIVE

Staphylococcus aureus fracture-related infections (FRIs) are associated with significant morbidity in part because conventional antibiotic therapies have limited ability to eradicate S. aureus in sessile states. Therefore, the objective of this study was to assess the feasibility of using Staphylococcal bacteriophages for FRI by testing the activity of a library of Staphylococcal bacteriophage therapeutics against historically preserved S. aureus FRI clinical isolates.

METHODS

Current Procedural Terminology codes were used to identify patients with FRI from January 1, 2021 to December 31, 2021. Preserved S. aureus FRI isolates from the cases were then tested against a library of 51 Staphylococcal bacteriophages from an American company. This was conducted by assessing the ability of bacteriophages to reduce bacterial growth over time. Growth inhibition greater than 16 h was considered adequate for this study.

RESULTS

All of the S. aureus preserved clinical isolates had at least one bacteriophage with robust lytic activity and six bacteriophages (11.8 %) had robust lytic activity to seven or more of the clinical isolates. However, 41 of the bacteriophages (80.4 %) had activity to less than three of the clinical isolates and no bacteriophage had activity to all the clinical isolates.

CONCLUSION

Our findings show that Staphylococcal bacteriophage therapeutics are readily available for S. aureus FRI clinical isolates. However, when correlated with the current barriers to using bacteriophages to treat FRI, designated Staphylococcal bacteriophage cocktails with broad spectrum activity should be created.

Proximal fracture line extension in humeral shaft fractures

Introduction

Humeral shaft fractures are common injuries treated by orthopaedic surgeons. The purpose of this study is to evaluate displaced diaphyseal humerus fractures and describe the incidence and characteristics associated with non or minimally displaced fracture line extension into the proximal metadiaphyseal region of the humerus.

Methods and materials

All adult patients with diaphyseal humeral shaft fractures located within the distal two-thirds of the humeral shaft, treated at a single level I trauma institution between 2007 and 2020, were retrospectively identified. 202 patients with 203 fractures of the humeral shaft were included. Fracture patterns were classified according to AO/OTA classification and fracture line extension into the proximal metadiaphyseal region was evaluated on radiographs. Patient demographics, management details, and radiographic outcomes were obtained from review of the electronic medical record.

Results

Of 203 diaphyseal humerus fractures, 11.8 % (n = 24) had non or minimally displaced proximal extension of their main fracture line. This included 43.7 % (n = 7) of all proximal third junction diaphyseal fractures, 10.7 % (n = 16) of all middle third diaphyseal fractures, and 2.6 % (n = 1) of all distal third diaphyseal fractures. Patients with proximal fracture extension were, on average, older (61.7 versus 44.4 years, p < 0.001), and a higher percentage were female (75 % versus 45.5 %, p < 0.01) compared to patients without fracture proximal extension. Fractures with proximal extension were all closed fractures (n = 24), were more often sustained from low-energy fall (87.5 % versus 35.2 %, p < 0.001), and were more often spiral type fractures (62.5 % versus 17.2 %). Fractures with proximal extension were more often treated non-operatively (58.3 % versus 42.1 %, p < 0.01), but were found to have a higher rate of nonunion after non-operative treatment (17.6 % versus 8.1 %) compared to fractures without proximal extension. All operatively treated fractures that had proximal metaphyseal extension were secured with a fixation construct to achieve fixation proximal to the extent of the fracture line, most often into the humeral head and neck. Operative management with proximal fixation into the humeral head was also pursued for a patient with nonunion, including persistent lucency of the proximal extension line, after failed non-operative treatment. Mean follow-up was 35.5 weeks (range: 0-607 weeks).

Conclusions

Proximal fracture line extension in the setting of diaphyseal humerus fractures is not uncommon. Detection and consideration of this sometimes subtle finding is important when planning to treat these injuries operatively.

Hospital transfer and delayed reduction of traumatic hip dislocations

INTRODUCTION

Native hip dislocations are high energy injuries that cause substantial patient morbidity. Expedient reduction has been demonstrated to improve patient outcomes. The objective of our study was to compare complication rates in patients with native hip dislocations who presented directly to a level-one trauma center with those transferred from an outside hospital (OSH). Our hypothesis was that those transferred from an OSH would experience a delay in reduction and subsequently would experience higher rates of avascular necrosis (AVN), post-traumatic arthritis (PTA), and need for secondary surgery.

MATERIAL AND METHODS

We conducted a retrospective chart review of all native hip dislocations from our level-one trauma center between January 2007 and December 2020. The initial query resulted 628 patients which was refined to 90 patients after excluding patients for incorrect diagnosis code or less than 6 months of follow-up. Our primary outcome was the development of AVN, PTA, and need for secondary surgery. Time from injury to reduction was recorded for all patients included.

RESULTS

For every one hour of delay in time to reduction, there was a 3.4% increase in the risk of developing AVN (p = 0.004) and a 4.3% increase in risk for developing PTA (p = 0.01). The risk of requiring a secondary surgery increased 4.6% for each hour of delay in reduction (p = 0.03). The average time to reduction of transferred patients was higher compared to those who presented directly to our center (13.8 h vs 5.7 h); however, transfer status was not found to be an independent risk factor for the measured outcomes.

CONCLUSIONS

Transfer status is not an independent risk factor for the development of AVN, PTA, or the need for a secondary surgery. However, transferred patients did experience an average delay of 8 h in time to reduction compared to those who presented directly to a trauma center. Of the 27 patients with a reduction delay greater than 12 h, 26 (96%) were transferred.

Chronic Warfarin Anticoagulation in Hip Fracture Patients Delays Surgery and Is Associated With Increased Risk of Postoperative Complications: A Multicenter Propensity-Score-Matched Analysis

OBJECTIVE

To evaluate the effect of warfarin on blood transfusion and postoperative complications in a low-energy hip fracture population compared with a non-anticoagulated comparison group.

DESIGN

Multicenter Retrospective Cohort.

SETTING

Three Urban Level I Academic Trauma Centers.

PATIENTS

Acute, low-energy, native hip fractures in patients 55 years of age or older on chronic warfarin anticoagulation, propensity score matched 1:2 to non-anticoagulated hip fracture patients meeting all other inclusion criteria.

MAIN OUTCOME MEASUREMENTS

Transfusion and postoperative complication rates.

RESULTS

Two hundred ten anticoagulated hip fracture patients were matched to 420 nonanticoagulated patients. A higher proportion of patients required blood transfusion in the warfarin cohort (52.4% vs. 43.3%, P < 0.001), attributable mostly to the subgroup of patients undergoing arthroplasty. Warfarin patients had higher incidence of overall 90-day complications (47% vs. 38%, P = 0.039) and readmissions (31.4% vs. 8.9%, P < 0.001). Day of surgery international normalized ratio (INR) did not influence transfusions or complications among warfarin patients. Warfarin patients undergoing surgery within 24 hours had no difference in transfusions and had fewer complications compared with those undergoing surgery after 24 hours. On multivariable logistic regression analysis, warfarin use and day of surgery INR were not predictors of transfusion or complications.

CONCLUSIONS

Patients on warfarin experienced longer time to surgery and higher incidence of overall transfusion and postoperative complications within 90 days of surgery. However, warfarin use and day of surgery INR was not independently associated with transfusions or complications. The reason for poorer outcomes in warfarin patients remains a topic of further investigation.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

The Utility of MRI With Multiacquisition Variable-Resonance Image Combination (MAVRIC) in Diagnosing Deep Total Hip Arthroplasty Infection

Background: The 2010 American Academy of Orthopaedic Surgeons Clinical Practice Guidelines report insufficient evidence to address the diagnostic efficacy of magnetic resonance imaging (MRI) for periprosthetic joint infection (PJI). Questions/Purposes: The purpose of this study was to determine the utility of MRI with multiacquisition variable-resonance image combination (MAVRIC) metal artifact suppression techniques in diagnosing PJI in the setting of total hip arthroplasty (THA). Methods: Multiacquisition variable-resonance image combination MRIs obtained of THAs between November 2012 and November 2016 were queried. Radiology reports were classified as positive (suspicious for infection), negative (no features of infection), or inconclusive (infection cannot be excluded or correlation with aspiration suggested if clinically concerned). Chart review identified cases of deep PJI according to the modified Musculoskeletal Infection Society criteria. Results: Of 2156 MRIs of THAs included, MRI was concerning for infection in 1.8% (n = 39), inconclusive in 1.2% (n = 26), and negative in 97.0% (n = 2091). Deep PJI was identified in 53 (2.5%) patients, 30 of whom (56.6%) had conclusively positive finding on MRI (false-negative rate: 43.4%, sensitivity: 56.6%). Of 2103 aseptic THAs, only 9 (0.4%) MRIs were read as suspicious for infection (false-positive rate: 0.4%; specificity: 99.6%). Conclusion: Magnetic resonance imaging with MAVRIC is a highly specific test for PJI with a low false-positive rate. This indicates that when clinicians are provided with an MRI that unexpectedly suggests infection, a formal evaluation for infection is indicated. In patients with otherwise equivocal diagnostic findings, MRI may help confirm, but not refute, a diagnosis of PJI. Prospective study with more experienced image reviewers may further support the use of MRI in PJI.

Identifying alternative antibiotics that elute from calcium sulfate beads for treatment of orthopedic infections

There has been increasing interest in the use of a synthetic absorbable calcium sulfate (CaSO₄ ) for local antibiotic delivery in orthopaedic infections. The purpose of this study was to quantify elution kinetics of six antibiotics (amikacin, meropenem, fosfomycin, minocycline, cefazolin, and dalbavancin) from a clinically relevant CaSO₄ bead model and compare elution and antimicrobial activity to the current clinical gold standards: vancomycin and tobramycin. Antibiotic-loaded synthetic CaSO₄ beads were immersed in phosphate buffered saline and incubated at 37°C. Eluent was harvested at eight time points over 28 days. Antibiotic concentrations were measured by high performance liquid chromatography to quantify elution rates. CaSO₄ beads demonstrated burst release kinetics. Dalbavancin, cefazolin, and minocycline all demonstrated similar elution profiles to vancomycin. Amikacin and meropenem demonstrated favorable elution profiles and durations of above-minimum inhibitory concentration when compared to tobramycin. Clinical Significance: This study provides important novel data regarding the utility of amikacin, meropenem and dalbavancin as alternative choices to place in CaSO₄ carriers when treating orthopaedic infections.

Delayed Surgery Does Not Reduce Transfusion Rates in Low-Energy Hip Fractures on Direct Oral Anticoagulants

OBJECTIVES

To compare transfusion rates in patients on direct oral anticoagulants (DOACs) with nonanticoagulated patients undergoing hip fracture surgery and, secondarily, to determine whether time to surgery or complications differ between these groups.

DESIGN

Multicenter retrospective cohort.

SETTING

Three tertiary care, academic, Level I trauma centers.

PATIENTS

Acute, operatively treated, low-energy hip fracture patients 55 years of age and older were included. Anticoagulated patients were matched in a 1:2 ratio to "control" nonanticoagulated hip fracture patients using propensity score matching.

MAIN OUTCOME MEASUREMENTS

The primary outcome was incidence of perioperative transfusion. The secondary outcomes included time to surgery, length of stay, and 90-day complications, readmissions, reoperations, and mortality.

RESULTS

One hundred thirty-two patients with hip fracture admitted on DOACs were identified (107 factor Xa inhibitors, 25 dabigatran) and were matched to 262 "control" nonanticoagulated patients. There was no difference in overall transfusion rates between anticoagulation and control groups (43.2%; n = 57 DOAC vs. 39.7%; n = 104 control; P = 0.517). The median time from admission to surgery was 41.7 hours in the DOAC group and 26.0 hours in the control group (P < 0.001). There were no differences in 90-day complication, readmission, reoperation, or mortality rates between DOAC and control groups. Comparing DOAC patients undergoing surgery within 24 hours and after 24 hours, there were no differences in transfusion rates (P = 0.558) or overall complication rates (P = 0.179).

CONCLUSIONS

This study supports growing evidence that DOAC use should not be a determining factor in delaying surgery for patients with hip fracture who are otherwise medically optimized.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

The performance of PROMIS computer adaptive testing for patient-reported outcomes in hip fracture surgery: a pilot study

INTRODUCTION

Patient-reported outcome measures (PROMs) are essential to patient-centered care in orthopaedics. PROMIS measures have demonstrated reliability, validity, responsiveness, and minimal floor and ceiling effects in various populations of patients receiving orthopaedic care but have not yet been examined in hip fracture patients. This pilot study sought to evaluate the psychometric performance of the PROMIS Physical Function (PROMIS PF) and Pain Interference (PROMIS PI) computer adaptive tests and compare these instruments with legacy outcome measures in hip fracture patients.

METHODS

This study included 67 patients who were 27-96 years old (median 76) and underwent osteosynthesis for a proximal femoral fracture. At 3, 6, and/or 12 months follow-up, patients completed both legacy (mHHS, SF-36-PCS, and VAS for pain) and PROMIS questionnaires (PROMIS PF and PROMIS PI). Respondent burden and floor/ceiling effects were calculated for each outcome measure. Correlation was calculated to determine concurrent validity between related constructs.

RESULTS

A strong correlation was found between PROMIS PF and mHHS (rho = 0.715, p < 0.001) and moderately strong correlation between PROMIS PF and SF-36 PCS (rho = 0.697, p < 0.001). There was also a moderately strong correlation between the VAS and the PROMIS PI (rho = 0.641, p < 0.001). Patients who completed PROMIS PF were required to answer significantly fewer questions as compared with legacy PROMs (mHHS, SF-36). For the PROMIS measures, 1% of patients completing PROMIS PF achieved the highest allowable score while 34% of patients completing PROMIS PI achieved the lowest allowable score. Of the legacy outcome measures, 31% of patients completing the VAS for pain achieved the lowest allowable score and 7% of patients completing the mHHS achieved the highest allowable score.

CONCLUSIONS

The results of this study support the validity of PROMIS CATs for use in hip fracture patients. The PROMIS PF was significantly correlated with SF-36 PCS and mHHS while requiring fewer question items per patient relative to the legacy outcome measures.

Thermal Stability and in Vitro Elution Kinetics of Alternative Antibiotics in Polymethylmethacrylate (PMMA) Bone Cement

BACKGROUND

Amikacin, meropenem, minocycline, and fosfomycin have potential clinical utility for orthopaedic infections; however, their suitability for use in polymethylmethacrylate (PMMA) is poorly understood. The purpose of this study was (1) to quantify the thermal stability of these antibiotics at clinically relevant temperatures and (2) to determine the elution pharmacodynamics of these alternative antibiotics in vitro from PMMA beads of different sizes.

METHODS

Polymerization temperatures of 10-mm PMMA beads were measured over time to generate a simulated heating curve. Aqueous solutions of tobramycin, amikacin, meropenem, minocycline, and fosfomycin were subjected to the temperature curves, followed by incubation at 37°C. Minimum inhibitory concentrations of each antibiotic were evaluated against Staphylococcus aureus, Escherichia coli, and Acinetobacter baumannii. High-dose 4.5-mm, 6-mm, and 10-mm antibiotic-laden PMMA beads (10% antibiotic by weight) were submerged individually in a phosphate-buffered saline solution and incubated at 37°C. Antibiotic elution was determined with use of high-performance liquid chromatography with mass spectrometry.

RESULTS

Tobramycin, amikacin, and fosfomycin demonstrated thermal stability and maintained antimicrobial activity for 28 days. Minocycline and meropenem lost antimicrobial activity against all 3 organisms after 48 hours and 7 days, respectively. Elution concentrations, rates, and cumulative drug mass for tobramycin, amikacin, and meropenem were orders of magnitude higher than minocycline and fosfomycin at each time point.

CONCLUSIONS

This study identified notable differences in thermal stability and elution among antibiotics used to treat infections. Amikacin exhibited activity similarly to tobramycin. Meropenem demonstrated favorable elution kinetics and thermal stability in the initial 7-day period.

CLINICAL RELEVANCE

Amikacin and meropenem show pharmacologic promise as potential acceptable alternatives for local delivery in PMMA for treatment of orthopaedic infections. Further work to establish clinical relevance and utility is needed.

Posterior Malleolus Fracture Displacement Is Associated with Rotational Ankle Fracture Stability in Patients Without Medial Malleolar Fractures

BACKGROUND

The optimal method for the determination of ankle stability remains controversial in rotational ankle fractures without medial bony injury.

QUESTIONS/PURPOSES

The purposes of this study were to (1) evaluate whether posterior malleolar (PM) fracture displacement is associated with deltoid ligament injury in supination-external rotation (SER) ankle fractures and (2) compare the diagnostic accuracy of PM displacement and magnetic resonance imaging (MRI) evaluation of the deep deltoid ligament in identifying fractures with deltoid ligament incompetence.

METHODS

Patients with rotational bimalleolar injuries containing lateral malleolar and PM fractures without bony medial injury were included. After operative lateral and PM fixation, an external rotation stress test was performed to evaluate deltoid ligament stability. Operative dictations were reviewed to confirm injury pattern, stability on stress test, and visual inspection of the deltoid ligament. Maximum PM displacement was assessed on lateral X-ray. Pre-operative MRI of the ankle was performed following closed reduction and splinting.

RESULTS

The final cohort consisted of 13 trimalleolar equivalent fractures (torn deltoid ligament) and 20 bimalleolar fractures (medial malleolus and deltoid ligament intact). Average PM displacement was significantly higher for SER trimalleolar equivalent patterns when measured on lateral X-ray. The sensitivity of detecting trimalleolar equivalent fracture was higher on all reported X-ray findings than the sensitivity obtained by the reported MRI findings of deltoid ligament injury.

CONCLUSION

PM displacement on X-ray is a useful adjuvant along with external rotation stress radiography and MRI evaluation of deep deltoid integrity to distinguish between stable and unstable fracture patterns and thus helps facilitate treatment decisions.

Intravenous tranexamic acid reduces blood loss and transfusion requirements after periacetabular osteotomy

AIMS

Tranexamic acid (TXA) has been shown to reduce blood loss and transfusion requirements in patients undergoing orthopaedic surgery. There remains a lack of prospective evidence for the use of TXA in patients undergoing periacetabular osteotomy (PAO). The purpose of this study was to determine if intravenous (IV) TXA is effective in reducing calculated blood loss and transfusions after PAO.

METHODS

This was a single-centre prospective double-blind placebo-controlled randomized trial of 81 patients aged 12 to 45 years undergoing elective PAO by a single surgeon. The intervention group (n = 40) received two doses of IV TXA of a maximum 1 g in each dose; the control group (n = 41) received two doses of 50 ml 0.9% saline IV. The primary outcome was perioperative calculated blood loss. Secondary outcomes included allogenic transfusions and six-week postoperative complications.

RESULTS

There were no differences in demographics or intraoperative variables between study groups. The TXA group demonstrated lower mean calculated blood loss (1,265 ml, (SD 321) vs 1,515 ml, (SD 394); p = 0.002) and lower frequency of allogenic transfusion (10%/n = 4 vs 37%/n = 15; p = 0.008). Regression analyses associated TXA use with significant reductions in calculated blood loss (p < 0.001) and transfusion (p = 0.007) after adjusting for age, sex, body mass index, preoperative haemoglobin, cell-saver volume, intraoperative mean arterial blood pressure, and operating time. No patients suffered venous thromboembolic complications.

CONCLUSION

In this trial, IV TXA decreased postoperative calculated blood loss by 293 ml and reduced the frequency of allogenic transfusions by 73% (37% vs 10%) following PAO. TXA may be safe and effective for reducing blood loss in patients undergoing PAO. Cite this article: Bone Joint J 2020;102-B(9):1151-1157.

Supination External Rotational Ankle Fracture Injury Pattern Correlation With Regional Bone Density

BACKGROUND:

Rotational ankle fractures can present with an array of possible osseous and ligamentous injury combinations in reliable anatomic locations. What accounts for these different injury patterns and whether specific patient and injury factors underlie the different injury patterns is unclear. The purpose of this study was to determine whether causative factors exist that could account for the various injury patterns seen with rotational ankle fractures.

METHODS:

A registry of operatively treated supination external rotation stage IV (SER IV) ankle fractures was used to identify patients. Computed tomography imaging was used to calculate regional bone density by using average Hounsfield unit measurements on axial images from the distal tibia and fibula. Patients were grouped into those with no posterior or medial malleolar fracture (equivalent group), those with either a posterior or medial malleolus fracture (bimalleolar group), and those with both posterior and medial malleolar fractures (trimalleolar group). Sixty-seven patients met inclusion criteria.

RESULTS:

Regional bone density at the ankle, as measured with Hounsfield units, was significantly higher in the equivalent group (371) than in the bimalleolar group (271, P < .0001) and trimalleolar group (228, P < .0001). Logistic regression analyses identified regional bone density as a significant predictor of a medial malleolus fracture ( P = .002) and of a posterior malleolus fracture ( P = .005).

CONCLUSION:

In our cohort of SER IV ankle fractures, regional bone density at the ankle significantly correlated with the presence and number of malleolar fractures compared with ligamentous ruptures. Treating surgeons can use this information to anticipate bone quality during operative fixation based on ankle fracture injury pattern. In addition, the presence of a trimalleolar ankle fracture was a significant indicator of poor bone quality and may represent the first clinical sign of abnormal bone metabolism in many patients.

LEVEL OF EVIDENCE:

Level III, prognostic retrospective cohort study.

Periprosthetic Joint Infection in Patients with Inflammatory Joint Disease: Prevention and Diagnosis

PURPOSE OF REVIEW

Periprosthetic joint infection (PJI) is a devastating complication that can occur following total joint arthroplasty (TJA), causing significant morbidity and often requiring revision surgery. This goal of this manuscript is to review the current evidence for the prevention and diagnosis of PJI in patients with inflammatory arthritis.

RECENT FINDINGS

Patients with inflammatory arthritis have a higher risk of PJI after TJA; however, there are several preventive, diagnostic, and therapeutic measures that can be optimized to lower the burden of PJI in this population. This manuscript will review the current evidence and clinical practice recommendations that support specific features of preoperative evaluation, perioperative medication management, and surgical planning in inflammatory arthritis patients undergoing TJA. Evidence and recommendations for the diagnosis of PJI in this patient population will also be reviewed. Despite increased research efforts directed towards PJI, specific approaches directed at the inflammatory arthritis patient population remain surprisingly limited. Optimization strategies such as adequately managing disease-modifying medications, treating preoperative anemia, encouraging smoking cessation, and improving weight management are strongly encouraged before entering the perioperative period. If PJI does occur in the inflammatory arthritis patient, establishing the diagnosis is challenging, since guidelines were created from investigations of PJI in primarily patients without inflammatory arthritis. Future prospective research is required to better guide clinicians in preventing and diagnosing PJI in inflammatory arthritis patients undergoing TJA.

The Use of Fibular Allograft in Complex Periarticular Fractures Around the Knee

Although the use of fibular strut allografts in proximal humerus fractures has gained popularity, their use in other types of fractures is less well described. Fibular allografts have recently been used in the repair of complex periarticular fractures of the proximal tibia and distal femur. Fibular allografts can be inserted in a variety of manners to achieve goals specific to each individual fracture pattern. In the proximal tibia, insertion through a fracture line or cortical window facilitates joint surface elevation, prevents subsidence and enhances overall construct stability. In distal femoral fractures, including complex periarticular fractures, insertion through the fracture or cortical window permits indirect reduction of the medial cortex and provides necessary medial column support. An additional option in distal femur fractures includes fibula insertion as an intramedullary nail, allowing enhanced fixation in short distal fracture segments. In all cases, the use of a fibular allograft augments poor bone stock and provides improved screw purchase and construct stability when combined with conventional plating methods. Here we present a series of cases at our institution illustrating an array of novel techniques utilizing endosteal fibular allografts in the fixation of complex periarticular fractures about the knee.

Validating the Patient Reported Outcomes Measurement Information System (PROMIS) computerized adaptive tests for upper extremity fracture care

BACKGROUND

Computerized adaptive testing (CAT) for patient-reported outcomes (PROs) is a developing area within orthopedic surgery. Our objective was to validate the Patient Reported Outcomes Measurement Information System (PROMIS) CATs for upper extremity fracture care. We sought to correlate PROMIS with legacy PROs and to investigate floor and ceiling effects.

METHODS

Patients who underwent open reduction and internal fixation of upper extremity trauma were prospectively enrolled. Legacy PROs included the visual analog scale for pain, the Disabilities of the Arm, Shoulder and Hand questionnaire, the University of California-Los Angeles Shoulder Rating Scale, the Mayo Elbow Performance Score, and the 36-Item Short Form Health Survey. PROMIS CATs included Physical Function (PROMIS PF), PROMIS Pain Interference (PROMIS Pain), and PROMIS Upper Extremity (PROMIS UE). Correlations between the PROs were calculated as were the absolute and relative floor and ceiling effect.

RESULTS

The study prospectively enrolled 174 patients with upper extremity trauma. There was moderate to high correlation between PROMIS UE CAT and legacy upper extremity-specific PROs (ρ = 0.42-0.79), and high correlation between the PROMIS PF CAT and the 36-Item Short Form Health Survey Physical Component Summary (ρ = 0.71, P < .001). The visual analog scale for pain, University of California-Los Angeles Shoulder Rating Scale, Constant Score, and Mayo Elbow Score demonstrated a significant absolute ceiling effect (20.5%-23.7%), whereas the PROMIS PF, PROMIS UE, and PROMIS Pain CATs demonstrated no absolute ceiling effect.

CONCLUSION

PROMIS PF, Pain, and UE correlate well with legacy PROs in a upper extremity trauma population, with less absolute floor or ceiling effects. This study provides preliminary evidence for the utility of PROMIS CATs in upper extremity trauma patients.

Bariatric Surgery Improves Outcomes After Lower Extremity Arthroplasty in the Morbidly Obese: A Propensity Score-Matched Analysis of a New York Statewide Database

BACKGROUND

The purpose of this study was to compare risks for revision and short-term complications after total joint arthroplasty (TJA) in matched cohorts of morbidly obese patients, receiving and not receiving prior bariatric surgery.

METHODS

Patients undergoing elective TJA between 1997 and 2011 were identified in a New York Statewide database, analyzing total knee arthroplasty (TKA) and total hip arthroplasty (THA) separately. Propensity scores were used to match morbidly obese patients receiving and not receiving bariatric surgery prior to TJA. Cox proportional hazard modeling assessed revision risk. Logistic regression evaluated odds for complications.

RESULTS

For TKA, 2636 bariatric surgery patients were matched to 2636 morbidly obese patients. For THA, 792 bariatric surgery patients were matched to 792 morbidly obese patients. Matching balanced all covariates. Bariatric surgery reduced co-morbidities prior to TJA (TKA P < .0001; THA P < .005). Risks for in-hospital complications were lower for THA and TKA patients receiving prior bariatric surgery (odds ratio [OR] 0.25, P < .001; and OR = 0.69, P = .021, respectively). Risks for 90-day complications were lower for TKA (OR 0.61, P = .002). Revision risks were not different for either THA (P = .634) or TKA (P = .431), nor was THA dislocation risk (P = 1.000).

CONCLUSION

After accounting for relevant selection biases, bariatric surgery prior to TJA was associated with reduced co-morbidity burden at the time of TJA and with reduced post-TJA complications. However, bariatric surgery did not reduce the risk for revision surgery for either TKA or THA.

Anabolic agents: what is beyond osteoporosis?

Osteoporosis is a common skeletal disorder characterized by low bone mass, which leads to reduced bone strength and an increased risk of fractures. Anabolic agents have been shown to improve bone mass and decrease fracture risk in osteoporosis patients by directly stimulating osteoblasts to produce new bone. Currently, two anabolic agents are available in the USA: recombinantly produced teriparatide (TPTD), which is the fully active (1-34) amino active sequence of human parathyroid hormone (PTH), and abaloparatide (APTD), a synthetic analog of parathyroid hormone-related peptide (PTHrP). At present, both agents are approved only for treatment of patients with osteoporosis at high risk of fracture. Nonetheless, their anabolic properties have led to off-label application in additional settings which include spine fusion, osteonecrosis of the jaw, arthroplasty, and fracture healing. In this article, we summarize available scientific literature regarding the efficacy, effectiveness, and safety of TPTD in these off-label settings.

Current Options and Emerging Biomaterials for Periprosthetic Joint Infection

PURPOSE OF REVIEW

Infection in the setting of total joint arthroplasty, referred to as periprosthetic joint infection (PJI), is a devastating complication requiring prolonged and costly treatment. The unique environment around an artificial joint and ability of surrounding tissues to sequester bacteria collectively make prevention, diagnosis, and treatment of this condition challenging. In light of the unique pathogenesis of PJI, this review explores the limitations of contemporary treatments and discusses novel treatment options.

RECENT FINDINGS

Recent advancements in local antibiotic delivery platforms for preventing and treating PJI include titanium nanotube arrays, synthetic polymers, resorbable hydrogels, and cyclodextrin-based drug delivery options. In particular, cyclodextrins have facilitated great advancements in other clinical disorders and have demonstrated early promise as a future option in the arena of PJI. Novel treatment modalities for PJI optimize the implant surfaces to prevent bacterial biofilm formation or provide prolonged intra-articular antibiotic dosing to eradicate bacteria.

Association of Epsilon-Aminocaproic Acid With Blood Loss and Risk of Transfusion After Periacetabular Osteotomy: A Retrospective Cohort Study

BACKGROUND

Periacetabular osteotomy (PAO) reorients the acetabular cartilage through a complex series of pelvic osteotomies, which risks significant blood loss often necessitating blood transfusion. Therefore, it is important to identify effective strategies to manage blood loss and decrease morbidity after PAO. The purpose of this study was to determine the association of epsilon-aminocaproic acid (EACA), an antifibrinolytic agent, with blood loss from PAO.

METHODS

Ninety-three patients out of 110 consecutive patients that underwent unilateral PAO for acetabular dysplasia met inclusion criteria. Fifty patients received EACA intraoperatively. Demographics, autologous blood predonation, anesthetic type, intraoperative estimated blood loss (EBL), cell-saver utilization, and transfusions were recorded. Total blood loss was calculated. Two-sample t-test and chi-square or Fisher's exact test were used as appropriate. The associations between EACA administration and calculated EBL, cell-saver utilization, intraoperative EBL, and maximum difference in postoperative hemoglobin were assessed via multiple regression, adjusting for confounders. Post hoc power analysis demonstrated sufficient power to detect a 250-mL difference in calculated EBL between groups. Alpha level was 0.05 for all tests.

RESULTS

No demographic differences existed between groups. Mean blood loss and allogeneic transfusion rates were not statistically significant between groups (P = .093 and .170, respectively). There were no differences in cell-saver utilization, intraoperative EBL, and/or postoperative hemoglobin. There was a higher rate of autologous blood utilization in the group not receiving EACA because of a clinical practice change.

CONCLUSIONS

EACA administration was not associated with a statistically significant reduction in blood loss or allogeneic transfusion in patients undergoing PAO.

Evaluating a measure of social health derived from two mental health recovery measures: the California Quality of Life (CA-QOL) and Mental Health Statistics Improvement Program Consumer Survey (MHSIP)

Social health is important to measure when assessing outcomes in community mental health. Our objective was to validate social health scales using items from two broader commonly used measures that assess mental health outcomes. Participants were 609 adults receiving psychological treatment services. Items were identified from the California Quality of Life (CA-QOL) and Mental Health Statistics Improvement Program (MHSIP) outcome measures by their conceptual correspondence with social health and compared to the Social Functioning Questionnaire (SFQ) using correlational analyses. Pearson correlations for the identified CA-QOL and MSHIP items with the SFQ ranged from .42 to .62, and the identified scale scores produced Pearson correlation coefficients of .56, .70, and, .70 with the SFQ. Concurrent validity with social health was supported for the identified scales. The current inclusion of these assessment tools allows community mental health programs to include social health in their assessments.

Predictors of doctor-rated and patient-rated gout severity: gout impact scales improve assessment

RATIONALE, AIMS AND OBJECTIVES

Our objective was to describe the factors associated with doctor-rated and patient-rated gout severity to explain how doctor assessment involving patient-reported outcomes can improve the clinical management of gout.

METHODS

Patients completed a newly validated gout-specific health-related quality of life instrument, the Gout Impact Scale (GIS) and other questions regarding their gout. Both patients and their doctors gave an overall gout severity assessment. We conducted correlation analyses between each predictor of interest and the two different severity ratings (doctor-rated severity and patient-rated severity). Stepwise multiple regressions were performed to determine the best predictors for doctor-rated and patient-rated severity, respectively.

RESULTS

Doctor-rated severity more closely correlated with objective clinical and laboratory findings, particularly the presence of tophi, which was not a leading factor in patient-rated severity assessments. Patient-rated severity more closely correlated with the domains of the GIS, which expressed the impact of gout on health-related quality of life.

CONCLUSION

Doctors might have a better understanding of their patients' level of disease impact if they incorporate an instrument such as the GIS in their evaluation of gout severity and their decisions regarding aggressiveness of treatment. The increased use of patient-reported outcomes measures has the potential to improve quality of care and patient satisfaction, as well as reduce costs of health care utilization.