bluuebunny/crossref_metadata_2025 huggingface dataset:
Outcomes following primary total hip arthroplasty with pre-existing spinal fusion surgery
Authors: Wyatt Michael C. , Kunutsor Setor K. , Beswick Andrew D. , Whitehouse Michael R. , Kieser David C.
Published: May 2020

Aims

There is inconsistent evidence on whether prior spinal fusion surgery adversely impacts outcomes following total hip arthroplasty (THA). We conducted a systematic review and meta-analysis to assess the association between pre-existing spinal fusion surgery and the rate of complications following primary THA.

Methods

We searched MEDLINE, Embase, Web of Science, and Cochrane Library up to October 2019 for randomized controlled trials (RCTs) and observational studies comparing outcomes of dislocation, revision, or reasons for revision in patients following primary THA with or without pre-existing spinal fusion surgery. Furthermore, we compared short (two or less levels) or long (three or more levels) spinal fusions to no fusion. Summary measures of association were relative risks (RRs) (with 95% confidence intervals (CIs)).

Results

We identified ten articles corresponding to nine unique observational studies comprising of 1,992,366 primary THAs. No RCTs were identified. There were 32,945 cases of spinal fusion and 1,752,362 non-cases. Comparing prior spinal fusion versus no spinal fusion in primary THA, RRs (95% CI) for dislocation was 2.23 (1.81 to 2.74; seven studies), revision 2.14 (1.63 to 2.83; five studies), periprosthetic joint infection 1.71 (1.53 to 1.92; four studies), periprosthetic fracture 1.52 (1.28 to 1.81; three studies), aseptic loosening 1.76 (1.54 to 2.01; three studies), and any complications 2.82 (1.37 to 5.80; three studies) were identified. Both short and long spinal fusions, when compared with no fusion, were associated dislocation, revision, or reasons for revision.

Conclusions

Patients with prior spinal fusion are at risk of adverse events following primary THA. Measures that reduce the risk of these complications should be considered in this high-risk population when undergoing primary THA. These patients should also be counselled appropriately around their risks of undergoing THA. Cite this article: Bone Joint J 2020;102-B(6):664–670.
Patient-reported outcomes in young patients with isolated fracture of the hip
Authors: Coughlin T. A. , Nightingale J. M. , Myint Y. , Forward D. P. , Norrish A. R. , Ollivere B. J.
Published: May 2020

Aims

Hip fractures in patients < 60 years old currently account for only 3% to 4% of all hip fractures in England, but this proportion is increasing. Little is known about the longer-term patient-reported outcomes in this potentially more active population. The primary aim is to examine patient-reported outcomes following isolated hip fracture in patients aged < 60 years. The secondary aim is to determine an association between outcomes and different types of fracture pattern and/or treatment implants.

Methods

All hip fracture patients aged 18 to 60 years admitted to a single centre over a 15-year period were used to identify the study group. Fracture pattern (undisplaced intracapsular, displaced intracapsular, and extracapsular) and type of operation (multiple cannulated hip screws, angular stable fixation, hemiarthroplasty, and total hip replacement) were recorded. The primary outcome measures were the Oxford Hip Score (OHS), the EuroQol five-dimension questionnaire (EQ-5D-3L), and EQ-visual analogue scale (VAS) scores. Preinjury scores were recorded by patient recall and postinjury scores were collected at a mean of 57 months (9 to 118) postinjury. Ethics approval was obtained prior to study commencement.

Results

A total of 72 patients were included. There was a significant difference in pre- and post-injury OHS (mean 9.8 point reduction (38 to -20; p < 0.001)), EQ-5D (mean 0.208 reduction in index (0.897 to -0.630; p < 0.001)), and VAS , and VAS (mean 11.6 point reduction (70 to -55; p < 0.001)) Fracture pattern had a significant influence on OHS (p < 0.001) with extracapsular fractures showing the least favourable long-term outcome. Fixation type also impacted significantly on OHS (p = 0.011) with the worst outcomes in patients treated by hemiarthroplasty or angular stable fixation.

Conclusion

There is a significant reduction in function and quality of life following injury, with all three patient-reported outcome measures used, indicating that this is a substantial injury in younger patients. Treatment with hemiarthroplasty or angular stable devices in this cohort were associated with a less favourable hip score outcome. Cite this article: Bone Joint J 2020;102-B(6):766–771.
CT planning studies for robotic total knee arthroplasty
Authors: Abdelfadeel Walaa , Houston Nicklaus , Star Andrew , Saxena Arjun , Hozack William J.
Published: May 2020

Aims

The aim of this study was to analyze the true costs associated with preoperative CT scans performed for robotic-assisted total knee arthroplasty (RATKA) planning and to determine the value of a formal radiologist’s report of these studies.

Methods

We reviewed 194 CT reports of 176 sequential patients who underwent primary RATKA by a single surgeon at a suburban teaching hospital. CT radiology reports were reviewed for the presence of incidental findings that might change the management of the patient. Payments for the scans, including the technical and professional components, for 330 patients at two hospitals were also recorded and compared.

Results

There were 82 incidental findings in 61 CT studies, one of which led to a recommendation for additional testing. Across both institutions, the mean total payment for a preoperative scan was $446 ($8 to $3,870). The mean patient payment was $71 ($0 to $2,690). There was wide variation in payments between the institutions. In Institution A, the mean total payment was $258 ($168 to $264), with a mean patient payment of $57 ($0 to $100). The mean technical payment in this institution was $211 ($8 to $856), while the mean professional payment was $48 ($0 to $66). In Institution B, the mean total payment was $636 ($37 to $3,870), with a mean patient payment of $85 ($0 to $2,690).

Conclusion

The total cost of a CT scan is low and a minimal part of the overall cost of the RATKA. No incidental findings identified on imaging led to a change in management, suggesting that the professional component could be eliminated to reduce costs. Further studies need to take into account the patient perspective and the wide variation in total costs and patient payments across institutions and insurances. Cite this article: Bone Joint J 2020;102-B(6 Supple A):79–84.
A lower threshold for revision of aseptic unicompartmental vs total knee arthroplasty
Authors: Johnson, Jr. William B. , Engh, Jr. C. Anderson , Parks Nancy L. , Hamilton William G. , Ho P. Henry , Fricka Kevin B.
Published: May 2020

Aims

It has been hypothesized that a unicompartmental knee arthroplasty (UKA) is more likely to be revised than a total knee arthroplasty (TKA) because conversion surgery to a primary TKA is a less complicated procedure. The purpose of this study was to determine if there is a lower threshold for revising a UKA compared with TKA based on Oxford Knee Scores (OKSs) and range of movement (ROM) at the time of revision.

Methods

We retrospectively reviewed 619 aseptic revision cases performed between December 1998 and October 2018. This included 138 UKAs that underwent conversion to TKA and 481 initial TKA revisions. Age, body mass index (BMI), time in situ, OKS, and ROM were available for all patients.

Results

There were no differences between the two groups based on demographics or time to revision. The top reasons for aseptic TKA revision were loosening in 212 (44%), instability in 88 (18%), and wear in 69 (14%). UKA revision diagnoses were primarily for loosening in 50 (36%), progression of osteoarthritis (OA) in 50 (36%), and wear in 17 (12%). Out of a maximum 48 points, the mean OKS of the UKAs before revision was 23 (SD 9.3), which was significantly higher than the TKAs at 19.2 (SD 9.8; p < 0.001). UKA patients scored statistically better on nine of the 12 individual OKS questions. The UKA cases also had a larger pre-revision mean ROM (114°, SD 14.3°) than TKAs (98°, SD 25°) ; p < 0.001).

Conclusion

At revision, the mean UKA OKSs and ROM were significantly better than those of TKA cases. This study suggests that at our institution there is a difference in preoperative OKS between UKA and TKA at the time of revision, demonstrating a revision bias. Cite this article: Bone Joint J 2020;102-B(6 Supple A):91–95.
Using pharmacogenetics to structure individual pain management protocols in total knee arthroplasty
Authors: Hamilton William G. , Gargiulo Jeanine M. , Parks Nancy L.
Published: May 2020

Aims

The purpose of this study was to use pharmacogenetics to determine the frequency of genetic variants in our total knee arthroplasty (TKA) patients that could affect postoperative pain medications. Pharmacogenetic testing evaluates patient DNA to determine if a drug is expected to have a normal clinical effect, heightened effect, or no effect at all on the patient. It also predicts whether patients are likely to experience side effects from medicine. We further sought to determine if changing the multimodal programme based on these results would improve pain control or reduce side effects.

Methods

In this pilot study, buccal samples were collected from 31 primary TKA patients. Pharmacogenetics testing examined genetic variants in genes OPRM1, CYP1A2, CYP2B6, CYP2C19, CYP3A4, CYP2C9, and CYP2D6. These genes affect the pharmacodynamics and pharmacokinetics of non-steroidal anti-inflammatory drugs and opioids. We examined the frequency of genetic variants to any of the medications we prescribed including celecoxib, hydrocodone, and tramadol. Patients were randomized to one of two groups: the control group received the standard postoperative pain regimen, and the study group received a customized regimen based on the pharmacogenetic results. For the first ten postoperative days, patients recorded pain scores, medication, and side effects.

Results

Genetic variants involving one or more medications in the multimodal pain protocol occurred in 13 of the 31 patients (42%). In total, eight patients (26%) had variants affecting more than one of the medications. For the 25 patients who recorded pain and medication logs, the mean pain levels and morphine equivalents (MEQs) consumed in the first ten days were higher in the control group than in the custom-guided group (p = 0.019 for pain and p = 0.655 for MEQ).

Conclusion

Overall, 42% of patients had a variant involving one of the pain medications prescribed in our perioperative pain program for TKA. Ongoing research will help determine if using these data to modify a patient’s medication will improve outcomes. Cite this article: Bone Joint J 2020;102-B(6 Supple A):73–78.
In vivo kinematics of deep lunges and sit-to-stand activities in patients with bicruciate-retaining total knee arthroplasty
Authors: Kwon Young-Min , Arauz Paul , Peng Yun , Klemt Christian
Published: May 2020

Aims

The removal of the cruciate ligaments in total knee arthroplasty (TKA) has been suggested as a potential contributing factor to patient dissatisfaction, due to alteration of the in vivo biomechanics of the knee. Bicruciate retaining (BCR) TKA allows the preservation of the cruciate ligaments, thus offering the potential to reproduce healthy kinematics. The aim of this study was to compare in vivo kinematics between the operated and contralateral knee in patients who have undergone TKA with a contemporary BCR design.

Methods

A total of 29 patients who underwent unilateral BCR TKA were evaluated during single-leg deep lunges and sit-to-stand tests using a validated computer tomography and fluoroscopic imaging system. In vivo six-degrees of freedom (6DOF) kinematics were compared between the BCR TKA and the contralateral knee.

Results

During single-leg deep lunge, BCR TKAs showed significantly less mean posterior femoral translation (13 mm; standard deviation (SD) 4) during terminal flexion, compared with the contralateral knee (16.6 mm, SD 3.7; p = 0.001). Similarly, BCR TKAs showed significantly less mean femoral rollback (11.6 mm (SD 4.5) vs 14.4 mm (SD 4.6); p < 0.043) during sit-to-stand. BCR TKAs showed significantly reduced internal rotation during many parts of the strenuous flexion activities particularly during high-flexion lunge (4° (SD 5.6°) vs 6.5° (SD 6.1°); p = 0.051) and during sit-to-stand (4.5° (SD 6°) vs 6.9° (SD 6.3°); p = 0.048).

Conclusion

The contemporary design of BCR TKA showed asymmetrical flexion-extension and internal-external rotation, suggesting that the kinematics are not entirely reproduced during strenuous activities. Future studies are required to establish the importance of patient factors, component orientation and design, in optimizing kinematics in patients who undergo BCR TKA. Cite this article: Bone Joint J 2020;102-B(6 Supple A):59–65.
Two-stage arthrodesis for complex, failed, infected total knee arthroplasty
Authors: Chalmers Brian P. , Matrka Alexis K. , Sems Stephen A. , Abdel Matthew P. , Sierra Rafael J. , Hanssen Arlen D. , Pagnano Mark W. , Mabry Tad M. , Perry Kevin I.
Published: May 2020

Aims

Arthrodesis is rarely used as a salvage procedure for patients with a chronically infected total knee arthroplasty (TKA), and little information is available about the outcome. The aim of this study was to assess the reliability, durability, and safety of this procedure as the definitive treatment for complex, chronically infected TKA, in a current series of patients.

Methods

We retrospectively identified 41 patients (41 TKAs) with a complex infected TKA, who were treated between 2002 and 2016 using a deliberate, two-stage knee arthrodesis. Their mean age was 64 years (34 to 88) and their mean body mass index (BMI) was 39 kg/m2 (25 to 79). The mean follow-up was four years (2 to 9). The extensor mechanism (EM) was deficient in 27 patients (66%) and flap cover was required in 14 (34%). Most patients were host grade B (56%) or C (29%), and limb grade 3 (71%), according to the classification of McPherson et al. A total of 12 patients (29%) had polymicrobial infections and 20 (49%) had multi-drug resistant organisms; fixation involved an intramedullary nail in 25 (61%), an external fixator in ten (24%), and dual plates in six (15%).

Results

Survivorship free from amputation, persistent infection, and reoperation, other than removal of an external fixator, at five years was 95% (95% confidence interval (CI) 89% to 100%), 85% (95% CI 75% to 95%), and 64% (95% CI 46% to 82%), respectively. Reoperation, other than removal of an external fixator, occurred in 13 patients (32%). After the initial treatment, radiological nonunion developed in ten knees (24%). Nonunion was significantly correlated with persistent infection (p = 0.006) and external fixation (p = 0.005). Of those patients who achieved limb salvage, 34 (87%) remained mobile and 31 (79%) had ‘absent’ or ‘minimal’ pain ratings.

Conclusion

Knee arthrodesis using a two-stage protocol achieved a survivorship free from amputation for persistent infection of 95% at five years with 87% of patients were mobile at final follow-up. However, early reoperation was common (32%). This is not surprising as this series included worst-case infected TKAs in which two-thirds of the patients had a disrupted EM, one-third required flap cover, and most had polymicrobial or multi-drug resistant organisms. Cite this article: Bone Joint J 2020;102-B(6 Supple A):170–175.
Incremental inputs improve the automated detection of implant loosening using machine-learning algorithms
Authors: Shah Romil F. , Bini Stefano A. , Martinez Alejandro M. , Pedoia Valentina , Vail Thomas P.
Published: May 2020

Aims

The aim of this study was to evaluate the ability of a machine-learning algorithm to diagnose prosthetic loosening from preoperative radiographs and to investigate the inputs that might improve its performance.

Methods

A group of 697 patients underwent a first-time revision of a total hip (THA) or total knee arthroplasty (TKA) at our institution between 2012 and 2018. Preoperative anteroposterior (AP) and lateral radiographs, and historical and comorbidity information were collected from their electronic records. Each patient was defined as having loose or fixed components based on the operation notes. We trained a series of convolutional neural network (CNN) models to predict a diagnosis of loosening at the time of surgery from the preoperative radiographs. We then added historical data about the patients to the best performing model to create a final model and tested it on an independent dataset.

Results

The convolutional neural network we built performed well when detecting loosening from radiographs alone. The first model built de novo with only the radiological image as input had an accuracy of 70%. The final model, which was built by fine-tuning a publicly available model named DenseNet, combining the AP and lateral radiographs, and incorporating information from the patient’s history, had an accuracy, sensitivity, and specificity of 88.3%, 70.2%, and 95.6% on the independent test dataset. It performed better for cases of revision THA with an accuracy of 90.1%, than for cases of revision TKA with an accuracy of 85.8%.

Conclusion

This study showed that machine learning can detect prosthetic loosening from radiographs. Its accuracy is enhanced when using highly trained public algorithms, and when adding clinical data to the algorithm. While this algorithm may not be sufficient in its present state of development as a standalone metric of loosening, it is currently a useful augment for clinical decision making. Cite this article: Bone Joint J 2020;102-B(6 Supple A):101–106.
Complications in the treatment of prosthetic joint infection
Authors: Hartzler Molly A. , Li Katherine , Geary Michael B. , Odum Susan Marie , Springer Bryan D.
Published: May 2020

Aims

Two-stage exchange arthroplasty is the most common definitive treatment for prosthetic joint infection (PJI) in the USA. Complications that occur during treatment are often not considered. The purpose of this study was to analyze complications in patients undergoing two-stage exchange for infected total knee arthroplasty (TKA) and determine when they occur.

Methods

We analyzed all patients that underwent two-stage exchange arthroplasty for treatment of PJI of the knee from January 2010 to December 2018 at a single institution. We categorized complications as medical versus surgical. The intervals for complications were divided into: interstage; early post-reimplantation (three months); and late post-reimplantation (three months to minimum one year). Minimum follow-up was one year. In total, 134 patients underwent a first stage of a two-stage exchange. There were 69 males and 65 females with an mean age at first stage surgery of 67 years (37 to 89). Success was based on the new Musculoskeletal Infection Society (MSIS) definition of success reporting.

Results

Overall, 70 (52%) patients experienced a complication during the planned two-stage treatment, 36 patients (27%) experienced a medical complication and 47 (41%) patients experienced a surgical complication. There was an 18% mortality rate (24/134) at a mean of 3.7 years (0.09 to 8.3). During the inter-stage period, 28% (37/134) of patients experienced a total of 50 complications at a median of 47 days (interquartile range (IQR) 18 to 139). Of these 50 complications, 22 were medical and 28 required surgery. During this inter-stage period, four patients died (3%) and an additional five patients (4%) failed to progress to the second stage. While 93% of patients (125/134) were reimplanted, only 56% (77/134) of the patients were successfully treated without antibiotic suppression (36%, 28/77) or with antibiotic suppression (19%, 15/77) at one year.

Conclusion

Reported rates of success of two stage exchanges for PJI have not traditionally considered complications in the definition of success. In our series, significant numbers of patients experienced complications, more often after reimplantation, highlighting the morbidity of this method of treatment. Cite this article: Bone Joint J 2020;102-B(6 Supple A):145–150.
2020 Mark Coventry Award: Microorganism-directed oral antibiotics reduce the rate of failure due to further infection after two-stage revision hip or knee arthroplasty for chronic infection: a multicentre randomized controlled trial at a minimum of two years
Authors: Yang JaeWon , Parvizi Javad , Hansen Erik N. , Culvern Chris N. , Segreti John C. , Tan Timothy , Hartman Curtis W. , Sporer Scott M. , Della Valle Craig J. ,   The Knee Society Research Group
Published: May 2020

Aims

The aim of this study was to determine if a three-month course of microorganism-directed oral antibiotics reduces the rate of failure due to further infection following two-stage revision for chronic prosthetic joint infection (PJI) of the hip and knee.

Methods

A total of 185 patients undergoing a two-stage revision in seven different centres were prospectively enrolled. Of these patients, 93 were randomized to receive microorganism-directed oral antibiotics for three months following reimplantation; 88 were randomized to receive no antibiotics, and four were withdrawn before randomization. Of the 181 randomized patients, 28 were lost to follow-up, six died before two years follow-up, and five with culture negative infections were excluded. The remaining 142 patients were followed for a mean of 3.3 years (2.0 to 7.6) with failure due to a further infection as the primary endpoint. Patients who were treated with antibiotics were also assessed for their adherence to the medication regime and for side effects to antibiotics.

Results

Nine of 72 patients (12.5%) who received antibiotics failed due to further infection compared with 20 of 70 patients (28.6%) who did not receive antibiotics (p = 0.012). Five patients (6.9%) in the treatment group experienced adverse effects related to the administered antibiotics severe enough to warrant discontinuation.

Conclusion

This multicentre randomized controlled trial showed that a three-month course of microorganism-directed, oral antibiotics significantly reduced the rate of failure due to further infection following a two-stage revision of total hip or knee arthroplasty for chronic PJI. Cite this article: Bone Joint J 2020;102-B(6 Supple A):3–9.
Can a gait-dependent model predict wear on retrieved total knee arthroplasty components?
Authors: Knowlton Christopher B. , Lundberg Hannah J. , Wimmer Markus A. , Jacobs Joshua J.
Published: May 2020

Aims

A retrospective longitudinal study was conducted to compare directly volumetric wear of retrieved polyethylene inserts to predicted volumetric wear modelled from individual gait mechanics of total knee arthroplasty (TKA) patients.

Methods

In total, 11 retrieved polyethylene tibial inserts were matched with gait analysis testing performed on those patients. Volumetric wear on the articular surfaces was measured using a laser coordinate measure machine and autonomous reconstruction. Knee kinematics and kinetics from individual gait trials drove computational models to calculate medial and lateral tibiofemoral contact paths and forces. Sliding distance along the contact path, normal forces and implantation time were used as inputs to Archard’s equation of wear to predict volumetric wear from gait mechanics. Measured and modelled wear were compared for each component.

Results

Volumetric wear rates on eight non-delaminated components measured 15.9 mm3/year (standard error (SE) ± 7.7) on the total part, 11.4 mm3/year (SE ± 6.4) on the medial side and 4.4 (SE ± 2.6) mm3/year on the lateral side. Volumetric wear rates modelled from patient gait mechanics predicted 16.4 mm3/year (SE 2.4) on the total part, 11.7 mm3/year (SE 2.1) on the medial side and 4.7 mm3/year (SE 0.4) on the lateral side. Measured and modelled wear volumes correlated significantly on the total part (p = 0.017) and the medial side (p = 0.012) but not on the lateral side (p = 0.154).

Conclusion

In the absence of delamination, patient-specific knee mechanics during gait directly affect wear of the tibial component in TKA. Cite this article: Bone Joint J 2020;102-B(6 Supple A):129–137.
Local delivery of tobramycin and vancomycin in primary total knee arthroplasty achieves minimum inhibitory concentrations for common bacteria causing acute prosthetic joint infection
Authors: Lawrie Charles M. , Jo Sally , Barrack Toby , Roper Stephen , Wright Rick W. , Nunley Ryan M. , Barrack Robert L.
Published: May 2020

Aims

The aim of this study was to determine if the local delivery of vancomycin and tobramycin in primary total knee arthroplasty (TKA) can achieve intra-articular concentrations exceeding the minimum inhibitory concentration thresholds for bacteria causing acute prosthetic joint infection (PJI).

Methods

Using a retrospective single-institution database of all primary TKAs performed between January 1 2014 and May 7 2019, we identified patients with acute PJI that were managed surgically within 90 days of the initial procedure. The organisms from positive cultures obtained at the time of revision were tested for susceptibility to gentamicin, tobramycin, and vancomycin. A prospective study was then performed to determine the intra-articular antibiotic concentration on postoperative day one after primary TKA using one of five local antibiotic delivery strategies with tobramycin and/or vancomycin mixed into the polymethylmethacrylate (PMMA) or vancomycin powder.

Results

A total of 19 patients with acute PJI after TKA were identified and 29 unique bacterial isolates were recovered. The mean time to revision was 37 days (6 to 84). Nine isolates (31%) were resistant to gentamicin, ten (34%) were resistant to tobramycin, and seven (24%) were resistant to vancomycin. Excluding one Fusobacterium nucleatum, which was resistant to all three antibiotics, all isolates resistant to tobramycin or gentamicin were susceptible to vancomycin and vice versa. Overall, 2.4 g of tobramycin hand-mixed into 80 g of PMMA and 1 g of intra-articular vancomycin powder consistently achieved concentrations above the minimum inhibitory concentrations of susceptible organisms.

Conclusion

One-third of bacteria causing acute PJI after primary TKA were resistant to the aminoglycosides commonly mixed into PMMA, and one-quarter were resistant to vancomycin. With one exception, all bacteria resistant to tobramycin were susceptible to vancomycin and vice versa. Based on these results, the optimal cover for organisms causing most cases of acute PJI after TKA can be achieved with a combination of tobramycin mixed in antibiotic cement, and vancomycin powder. Cite this article: Bone Joint J 2020;102-B(6 Supple A):163–169.
Preoperative cut-off values for body mass index deny patients clinically significant improvements in patient-reported outcomes after total hip arthroplasty
Authors:   Cleveland Clinic OME Arthroplasty Group, Arnold Nicholas , Anis Hiba , Barsoum Wael K. , Bloomfield Michael R. , Brooks Peter J. , Higuera Carlos A. , Kamath Atul F. , Klika Alison , Krebs Viktor E. , Mesko Nathan W. , Molloy Robert M. , Mont Michael A. , Murray Trevor G. , Patel Preteesh D. , Strnad Gregory , Stearns Kim L. , Warren Jared , Zajichek Alexander , Piuzzi Nicolas S.
Published: May 2020

Aims

Thresholds for operative eligibility based on body mass index (BMI) alone may restrict patient access to the benefits of arthroplasty. The purpose of this study was to evaluate the relationship between BMI and improvements in patient-reported outcome measures (PROMs), and to determine how many patients would have been denied improvements in PROMs if BMI cut-offs were to be implemented.

Methods

A prospective cohort of 3,449 primary total hip arthroplasties (THAs) performed between 2015 and 2018 were analyzed. The following one-year PROMs were evaluated: hip injury and osteoarthritis outcome score (HOOS) pain, HOOS Physical Function Shortform (PS), University of California, Los Angeles (UCLA) activity, Veterans Rand-12 Physical Component Score (VR-12 PCS), and VR-12 Mental Component Score (VR-12 MCS). Positive predictive values for failure to improve and the number of patients denied surgery in order to avoid a failed improvement were calculated for each PROM at different BMI cut-offs.

Results

There was a trend to improved outcomes in terms of pain and function improvements with higher BMI. Patients with BMI ≥ 40 kg/m2had median (Q1, Q3) HOOS pain improvements of 58 points (interquartile range (IQR) 41 to 70) and those with BMI 35 to 40 kg/m2had median improvements of 55 (IQR 40 to 68). With a BMI cut-off of 30 kg/m2, 21 patients would have been denied a meaningful improvement in HOOS pain score in order to avoid one failed improvement. At a 35 kg/m2cut-off, 18 patients would be denied improvement, at a 40 kg/m2cut-off 21 patients would be denied improvement, and at a 45 kg/m2cut-off 21 patients would be denied improvement. Similar findings were observed for HOOS-PS, UCLA, and VR-12 scores.

Conclusion

Patients with higher BMIs show greater improvements in PROMs. Using BMI alone to determine eligibility criteria did not improve the rate of clinically meaningful improvements. BMI thresholds prevent patients who may benefit the most from surgery from undergoing THA. Surgeons should consider PROMs improvements in determining eligibility for THA while balancing traditional metrics of preoperative risk stratification. Cite this article: Bone Joint J 2020;102-B(6):683–692.
Saline lavage after a “dry tap”
Authors: Heckmann Nathanael D. , Nahhas Cindy R. , Yang JaeWon , Della Valle Craig J. , Yi Paul H. , Culvern Chris N. , Gerlinger Tad L. , Nam Denis
Published: May 2020

Aims

In patients with a “dry” aspiration during the investigation of prosthetic joint infection (PJI), saline lavage is commonly used to obtain a sample for analysis. The aim of this study was to investigate prospectively the impact of saline lavage on synovial fluid analysis in revision arthroplasty.

Methods

Patients undergoing revision hip (THA) or knee arthroplasty (TKA) for any septic or aseptic indication were enrolled. Intraoperatively, prior to arthrotomy, the maximum amount of fluid possible was aspirated to simulate a dry tap (pre-lavage) followed by the injection with 20 ml of normal saline and re-aspiration (post-lavage). Pre- and post-lavage synovial white blood cell (WBC) count, percent polymorphonuclear cells (%PMN), and cultures were compared.

Results

A total of 78 patients had data available for analysis; 17 underwent revision THA and 61 underwent revision TKA. A total of 16 patients met modified Musculoskeletal Infection Society (MSIS) criteria for PJI. Pre- and post-lavage %PMNs were similar in septic patients (87% vs 85%) and aseptic patients (35% vs 39%). Pre- and post-lavage synovial fluid WBC count were far more disparate in septic (53,553 vs 8,275 WBCs) and aseptic (1,103 vs 268 WBCs) cohorts. At a cutoff of 80% PMN, the post-lavage aspirate had a sensitivity of 75% and specificity of 95%. At a cutoff of 3,000 WBCs, the post-lavage aspirate had a sensitivity of 63% and specificity of 98%. As the post-lavage synovial WBC count increased, the difference between pre- and post-lavage %PMN decreased (mean difference of 5% PMN in WBC < 3,000 vs mean difference 2% PMN in WBC > 3,000, p = 0.013). Of ten positive pre-lavage fluid cultures, only six remained positive post-lavage.

Conclusion

While saline lavage aspiration significantly lowered the synovial WBC count, the %PMN remained similar, particularly at WBC counts of > 3,000. These findings suggest that in patients with a dry-tap, the %PMN of a saline lavage aspiration has reasonable sensitivity (75%) for the detection of PJI. Cite this article: Bone Joint J 2020;102-B(6 Supple A):138–144.
Heterogeneity of circulating tumor cell dissemination and lung metastases in a subcutaneous Lewis lung carcinoma model
Authors: Fitzgerald Jessica E. , Byrd Brook K. , Patil Roshani A. , Strawbridge Rendall R. , Davis Scott C. , Bellini Chiara , Niedre Mark
Published: May 2020

Subcutaneous (s.c.) tumor models are widely used in pre-clinical cancer metastasis research. Despite this, the dynamics and natural progression of circulating tumor cells (CTCs) and CTC clusters (CTCCs) in peripheral blood are poorly understood in these models. In this work, we used a new technique called ‘diffuse in vivo flow cytometry’ (DiFC) to study CTC and CTCC dissemination in an s.c. Lewis lung carcinoma (LLC) model in mice. Tumors were grown in the rear flank and we performed DiFC up to 31 days after inoculation. At the study endpoint, lungs were excised and bioluminescence imaging (BLI) was performed to determine the extent of lung metastases. We also used fluorescence macro-cryotome imaging to visualize infiltration and growth of the primary tumor. DiFC revealed significant heterogeneity in CTC and CTCC numbers amongst all mice studied, despite using clonally identical LLC cells and tumor placement. Maximum DiFC count rates corresponded to 0.1 to 14 CTCs per mL of peripheral blood. In general, CTC numbers did not necessarily increase monotonically over time and were poorly correlated with tumor volume. However, there was a good correlation between CTC and CTCC numbers in peripheral blood and lung metastases. We attribute the differences in CTC numbers primarily due to growth patterns of the primary tumor. This study is one of the few reports of CTC shedding dynamics in sub-cutaneous metastasis models and underscores the value of in vivo methods for continuous, non-invasive CTC monitoring.
Waveguide tapering for improved parametric amplification in integrated nonlinear Si3N4 waveguides
Authors: Zhao Ping , Ye Zhichao , Vijayan Kovendhan , Naveau Corentin , Schröder Jochen , Karlsson Magnus , Andrekson Peter A.
Published: May 2020

In this paper, we propose and numerically investigate waveguide tapering to improve optical parametric amplification in integrated nonlinear Si3N4 circuits. The phase matching condition of parametric amplification changes along the length of uniform Si3N4 waveguides, due to the non-negligible propagation loss, potentially causing peak-gain wavelength shifts of more than 20 nm. By tapering the waveguide width along propagation, we can achieve a 2.5 dB higher maximum parametric gain thanks to the improved phase matching, which can also broaden the amplification bandwidth. Therefore, the length of an optimally tapered Si3N4 waveguide can be 23% shorter than a uniform one in the case of a 3.0 dB/m propagation loss and a single continuous-wavelength pump. Quasi-continuous tapers are efficient to approximate continuous ones and might simplify the fabrication of long tapered nonlinear Si3N4 waveguides, which are promising for optical signal processing and optical communications.
Low spurious optoelectronic oscillator achieved by frequency conversion filtering without deteriorating phase noise
Authors: Guan Shanhong , Cen Qizhuang , Yin Feifei , Xu Kun , Dai Yitang
Published: May 2020

In order to obtain microwave signals with low spurs and low phase noise, we studied the residual phase noise of the frequency-conversion filtering oscillator and methods to improve its phase noise performance. We first analyze the influence of the dispersion of the intermediate frequency (IF) filter on the residual phase noise in the frequency conversion filtering process. Then, we use an electro-optic modulator to achieve up-conversion in the frequency conversion filtering and extend the intra-cavity delay with an optical fiber after the modulator. This allows the optoelectronic oscillator (OEO) to improve the phase noise performance while having a good suppression of spurs. The spurs suppression ratio of the proposed OEO is 80 dB with a fiber of about 1.6 km in the cavity. The phase noise of the proposed OEO is −130 dBc/Hz at 10 kHz offset from 10 GHz, which is 10 dB lower than our previous work.
Control of Diesel-electric AC/DC Traction Drive of Motor Truck WŽB 10.1-M
Authors: Mašek Zdeněk , Novák Jaroslav , Sadílek Ondřej , Lelek Tomáš
Published: June 2020

The paper describes the control of traction drive and control systems properties of a special rail vehicle WŽB10.1-M used in the Prague metro (subway).  Measured values of main quantities of the control system and experience from duty are included. Software for the traction drive control system was developed at the University of Pardubice.
Cancer alertness in patients with rheumatic diseases
Authors: Sycheva A. S. , Lila A. M. , Vertkin A. L. , Khlanta D. A.
Published: May 2020

The processes that vary in nature and underlie the pathogenesis of malignant neoplasms (MNs) and immune-mediated inflammatory rheumatic diseases (RDs) share just the same some common features. Thus, many early-stage neoplasias can mask autoimmune diseases, requiring that physicians of various specialties should comply with the principle of cancer alertness. When specific cancer treatments (immunotherapy, cytostatic therapy, radiotherapy) are performed, there may be certain rheumatic syndromes (arthritis, myalgia, serositis, etc.) that require a differential diagnosis. At the same time, the course of a number of RDs (rheumatoid arthritis, Sjögren's syndrome, and polymyositis) can be accompanied by the development of MNs, which is relevant for real clinical practice and calls for further investigation.The community of etiological factors and a genetic predisposition in the development of RDs and MNs remain to be of no less importance. At the same time, therapists should pay attention to the presence of rheumatic masks in many MNs, which undoubtedly prolongs the time between onset of the first symptoms and correct diagnosis.
The place of nonsteroidal anti-inflammatory drugs in the current osteoarthritis guidelines
Authors: Taskina E. A. , Kashevarova N. G. , Alekseeva L. I.
Published: May 2020

The paper provides a review of the data available in the literature on the relationship of pain to the risk of OA progression. Network analyses and numerous studies, including those conducted at the V.A. Nasonova Research Institute of Rheumatology, have confirmed that pain syndrome is one of the significant predictors of knee OA progression. The major class of medications for OA pain includes nonsteroidal anti-inflammatory drugs. The paper gives data on the efficacy of meloxicam in OA patients, which is widely used in both Russia and other countries of the world. Meloxicam is characterized by a good safety profile in the gastrointestinal tract, cardiovascular and renal systems. It is the drug of choice in patients with musculoskeletal diseases, in particular OA. Good results in severe pain syndrome have been shown by a step-by-step regimen of meloxicam when the injection formulation of the drug is used in the first days of treatment, and then, to consolidate what has been gained from therapy, its oral dosage form is administered in terms of concomitant diseases.
Fibromyalgia: clinical presentation and variants of the disease
Authors: Teplyakova O. V. , Popov A. A. , Volkova L. I. , Sarapulova A. V.
Published: May 2020

Fibromyalgia (FM) is a condition characterized by generalized pain syndrome and by the presence of fatigue, cognitive impairment, affective and multiple somatic symptoms. Pain syndrome can have national, ethnic, gender, and age characteristics.Objective: to evaluate the features of the course of FM in a large industrial center of the Russian Federation and to present its phenotypic options.Patients and methods. The investigation enrolled 92 FM patients (8 men, 84 women) aged 18 to 86 years (mean age, 50.5 years). The diagnosis was established according to the 2016 ACR criteria. Account was taken of data on disease duration, occupation, sport training loads, previous therapy, pain intensity, and somatic symptoms according to the 2010 ACR diagnostic criteria and on general health assessment in the patients. All the patients completed the hospital anxiety and depression scale (HADS).Results and discussion. The most significant somatic symptoms in the clinical picture of FM were shown to be muscle pain and muscle weakness, the manifestations of irritable bowel syndrome and fatigue; moreover, the prevalence of many symptoms in people over 60 years of age was lower than that in younger patients. Female gender was an additional risk factor for increases in pain and cognitive impairment. The presence of concomitant depression verified by HADS was associated with a substantial deterioration of the clinical manifestations of FM. At the same time, professional activities and sports were found to be protective factors against a number of symptoms of FM. It was hypothesized that there were several FM phenotypes (anxious, anxiety-depressive, egocentric, and vascular ones).Conclusion. The authors have demonstrated the features of the course of FM in a large industrial center of the Russian Federation and identified various disease phenotypes, which can be useful for determining the treatment policy for patients.
The gene expression of caspase 3, matrix metalloproteinase-9, tissue inhibitor of metalloproteinases-1, and cathepsins S and K in patients with osteoarthritis requiring large joint replacement
Authors: Chetina E. V. , Glemba K. E. , Markova G. A. , Makarov S. A.
Published: May 2020

Osteoarthritis (OA) is a chronic rheumatic disease that is characterized by pain and articular cartilage degradation. Pain in OA is a main clinical symptom that limits working capacity and is one of the indications for joint replacement. However, 10-40% of patients with OA also continue to experience painful sensations after surgery.Objective: to develop a method for searching for biomarkers to predict the dynamics of pain in the postoperative period and to determine the feasibility of arthroplasty on the basis of a retrospective analysis of relative blood gene expression prior to surgery.Patients and methods. The investigators tested the blood taken from 53 OA patients (mean age, 56.5±8.9 years) before knee arthroplasty and from 26 healthy donors (mean age, 55±8.3 years). Total RNA was isolated from blood and after reverse transcription into complementary DNA was used to measure the level of relative gene expression in real-time polymerase chain reaction.Results and discussion. A retrospective analysis of the expression of genes associated with central sensitization in 53 patients with OA before arthroplasty showed that the data on the expression of tumor necrosis factor-α, interleukin-1β, cyclooxygenase-2, and transforming growth factor β1 were uninformative due to their high blood expression in all the patients. The high gene expression of cathepsin S (in 17% of the patients) and cathepsin K (in 21%) and the low gene expression of tissue inhibitor of metalloproteinases 1 (TIMP-1) (in 31%) may indicate that postoperative pain can be persistent. In contrast, no post-arthroplasty pain can be expected in 43% OA patients with low caspase 3 expression and in 23% of those with low MMP-9 one.Conclusion. Analysis of pre-arthroplasty blood gene expression in patients with OA seems to be a promising approach to predicting the dynamics of pain after surgical treatment.
Diabetes mellitus in patients with rheumatoid arthritis in the Republic of Karelia
Authors: Koryakova N. V. , Polskaya I. I. , Marusenko I. M. , Kulagina T. I.
Published: May 2020

Objective: to estimate the incidence of diabetes mellitus (DM) in patients with rheumatoid arthritis (RA) in the Republic of Karelia and to analyze the types of carbohydrate metabolism disorders.Patients and methods. The investigation enrolled 889 patients aged 18 years and older with RA treated in the Rheumatology Department, V.A. Baranov Republican Hospital (Petrozavodsk), in 2000 to 2019. Among them, there were 709 (79.8%) women and 180 (20.2%) men; the median age was 59 [52; 66] years; the median duration of RA was 6.5 [1.75; 13] years. Most patients were found to have positive rheumatoid factor (68.3%), the second and more advanced radiological stages (90.6%), and moderate and high RA disease activity (84.8%). Methotrexate as a mainstay disease-modifying anti-rheumatic drug was taken by 68.2%; biological agents and glucocorticoids (GCs) were used in 4.8 and 3.3%, respectively. The incidence of DM and its types and risk factors (RFs) were analyzed.Results and discussion. DM was recorded in 67 (7.5%) RA patients (55 women and 12 men; the median age was 62 [56; 66] years). Among these patients, 9 (1.0%) patients with RA were observed to have type 1 DM, 50 (5.6%) and 8 (0.9%) patients had steroid-induced DM (SIDM), and type 2 DM, respectively. In 55.5% of cases, type 1 DM was represented by latent autoimmune diabetes in adults (LADA), which is of late onset. SIDM was detected in 75% of patients over 60 years of age who had RFs for type 2 DM. In this study, the incidence of type 2 DM in RA patients exceeded official figures in the general population of the Russian Federation, but was close to the predicted prevalence rates of type 2 DM. Patients with RA and type 2 DM had major RFs, such as age over 45 years, hypertension, overweight or obesity; moreover, 60% of patients were found to have a combination of these factors.Conclusion. RA patients showed a higher incidence rate of carbohydrate disorders of different types; the number of cases of type 1 DM and type 2 DM among the examined patients with RA exceeded that in the regional DM registries in the general population in the Republic of Karelia. It seems advisable to screen for carbohydrate disorders in patients with RA, especially in the presence of RFs for type 2 DM and during systemic therapy with GCs.
Assessing the status of patients with rheumatoid arthritis: modern tendencies
Authors: Lila A. M. , Olyunin Yu. A. , Gordeev A. V.
Published: May 2020

Assessing the status of a patient with rheumatoid arthritis allows one to obtain information necessary to choose appropriate management tactics for the patient. The use of quantitative methods in routine practice to determine inflammatory activity is the basis for the development of standardized patient management recommendations and provides a substantial improvement in the quality of health care. At the same time, the accumulated experience suggests that the existing summary indices do not always allow one to correctly determine disease activity. The paper discusses factors that can corrupt the result of assessment of inflammatory activity, as well as approaches to eliminating possible errors.