Treatment Outcomes of Fungal Periprosthetic Joint Infection.

BACKGROUND: Periprosthetic joint infection (PJI) continues to challenge surgeons and patients. The burden of fungal organisms may represent approximately 1% of all PJI. Additionally, fungal PJI is difficult to treat. Most available case series are small and report poor success rates. Fungi are opportunistic pathogens and patients who have fungal PJI are believed to be immunocompromised. Additionally, fungal biofilms are more complex than those formed by other pathogens and confer additional drug resistance. Due to these factors, treatment failure is common. METHODS: A retrospective review of our institutional registry was performed to identify patients treated for fungal PJI. There were 49 patients identified with 8 excluded for not having follow-up, which left 22 knees and 19 hips for analyses. Demographics, clinical characteristics, and surgical details were collected. The primary outcome was failure defined as reoperation for infection following the index surgery for fungal PJI within 1 year of the index surgery. RESULTS: Failure occurred in 10 of 19 knees and 11 of the 22 hips. A higher proportion of patients who have extremity grade C failed treatment, and every patient who failed was host grade 2 or 3. The average number of prior surgeries and time from resection to reimplantation were similar between groups. CONCLUSION: To our knowledge, this represents the largest cohort of fungal PJIs reported in the literature to date. This data supports other literature in that failure rates were high. More study is needed to further understand this entity and improve care for these patients.

Does Treatment at a Specialized Prosthetic Joint Infection Center Improve the Rate of Reimplantation.

BACKGROUND: Two-stage exchange arthroplasty is currently the preferred treatment method for periprosthetic joint infection (PJI). The effectiveness of this strategy in returning patients to premorbid function has recently been challenged. In a review of 18,535 PJI knee patients, 38% did not undergo reimplantation. In another review of 18,156 hip and knee PJI patients, 43% did not undergo reimplantation. These disturbing statistics led us to ask whether treatment at a specialized PJI center could improve the rate of reimplantation compared to the previously noted studies from large national administrative databases. METHODS: A retrospective review of our registry was performed to identify 390 patients who underwent a two-stage exchange after total knee arthroplasty and total hip arthroplasty who had a confirmed chronic bacterial PJI, defined by Musculoskeletal Infection Society criteria, from January 2010 through December 2019. Variables included number of joints resected, number reimplanted, and the number not reimplanted. RESULTS: Of the 390 patients undergoing 2-stage treatment, 386 of 390 (99%) were reimplanted and 4 of 390 (1%) were not reimplanted due to medical issues. CONCLUSION: We have shown that 2-stage treatment at a PJI center significantly improves the rate of reimplantation. A specialized PJI center with experienced revision surgeons doing high volume infection procedures complemented by infectious disease and medical consultants familiar with the special needs of PJI patients may be advantageous. A national network of such centers may have the ability to improve outcomes, standardize treatment protocols, and allow for collaborative research.

Hypoalbuminemia Predicts Failure of Two-Stage Exchange for Chronic Periprosthetic Joint Infection of the Hip and Knee.

BACKGROUND: Nutritionally compromized patients, with preoperative serum albumin (SAB) < 3.5g/dL, are at higher risk for periprosthetic joint infection (PJI) in total joint arthroplasty. The relationship between nutritional and PJI treatment success is unknown. The purpose of this study was to examine the relationship between preresection nutrition and success after first-stage resection in planned two-stage exchange for PJI. METHODS: A retrospective review was performed on 418 patients who had first-stage resection of a planned two-stage exchange for chronic hip or knee PJI between 2014 and 2018. A total of 157 patients (58 hips and 99 knees) were included who completed first stage, had available preop SAB and had a 2-year follow-up. Failure was defined as persistent infection or repeat surgery for infection after resection. Demographic and surgical data were abstracted and analyzed. RESULTS: Among knee patients with preop SAB >3.5 g/dL, the failure rate was 32% (15 of 47) versus a 48% (25 of 40) failure rate when SAB <3.5 g/dL (P = .10). Similarly, the failure rate among hip patients with preop SAB >3.5 g/dL versus 12.5% (3 of 24) versus 44% (15 of 34) for hip patients with SAB <3.5 g/dL (P = .01). Multivariable regression results indicated that patients with SAB< 3.5 g/dL (P = .0143) and Musculoskeletal Infection Society host type C (P = .0316) were at an increased risk of failure. CONCLUSION: Low preoperative SAB and Musculoskeletal Infection Societyhost type-C are independent risk factors for failure following first-stage resection in planned two-stage exchange for PJI. Efforts to nutritionally optimize PJI patients, when possible, may improve the outcome of two-stage exchange.

External Validation of Natural Language Processing Algorithms to Extract Common Data Elements in THA Operative Notes.

BACKGROUND: Natural language processing (NLP) systems are distinctive in their ability to extract critical information from raw text in electronic health records (EHR). We previously developed three algorithms for total hip arthroplasty (THA) operative notes with rules aimed at capturing (1) operative approach, (2) fixation method, and (3) bearing surface using inputs from a single institution. The purpose of this study was to externally validate and improve these algorithms as a prerequisite for broader adoption in automated registry data curation. METHODS: The previous NLP algorithms developed at Mayo Clinic were deployed and refined on EHRs from OrthoCarolina, evaluating 39 randomly selected primary THA operative reports from 2018 to 2021. Operative reports were available only in PDF format, requiring conversion to "readable" text with Adobe software. Accuracy statistics were calculated against manual chart review. RESULTS: The operative approach, fixation technique, and bearing surface algorithms all demonstrated perfect accuracy of 100%. By comparison, validated performance at the developing center yielded an accuracy of 99.2% for operative approach, 90.7% for fixation technique, and 95.8% for bearing surface. CONCLUSION: NLP algorithms applied to data from an external center demonstrated excellent accuracy in delineating common elements in THA operative notes. Notably, the algorithms had no functional problems evaluating scanned PDFs that were converted to "readable" text by common software. Taken together, these findings provide promise for NLP applied to scanned PDFs as a source to develop large registries by reliably extracting data of interest from very large unstructured data sets in an expeditious and cost-effective manner.

Polymicrobial Colonization of Prosthetic Joint Infections Treated With Open Wound Management.

BACKGROUND: Open wound management in prosthetic joint infection (PJI) patients has been used in problematic dehisced wounds hoping to stimulate granulation tissue and closure. However, infections that start as a monomicrobial PJI can become polymicrobial with resultant worse outcomes following open wound management. This study assessed the relationship between open wound management and the development of polymicrobial periprosthetic joint infections. METHODS: We reviewed patients referred with a synovial cutaneous fistula. Patients with an open wound measuring less than 2 cm and less than two weeks of open wound management were excluded. Variables included original organisms cultured, type and length of open wound management, and organisms cultured at the time of revision infection surgery. RESULTS: Of the 65 patients with a previous monomicrobial infection treated with open wound management, 22/65 (34%) progressed to a polymicrobial infection. Thirty (46%) wounds were packed open with gauze, 20 (31%) were managed with negative pressure wound therapy, and 15 (23%) had surface dressings only. Of the 22 patients who converted to a polymicrobial infection, only 10 (45%) were infection free at follow-up. In contrast, 30 of 43 patients (70%) whose infections remained monomicrobial were infection free at follow-up. CONCLUSION: Open wound management can lead to conversion from a monomicrobial to a polymicrobial PJI, a rate of 34% in this series. Open prosthetic wound management should be discontinued for a fear of converting a monomicrobial infection to a difficult to treat polymicrobial infection. Surgeons must be prudent in the use of open wound management. LEVEL OF EVIDENCE: Level IV, Retrospective Case Series.

Do Pre-Reimplantation Erythrocyte Sedimentation Rate/C-Reactive Protein Cutoffs Guide Decision-Making in Prosthetic Joint Infection? Are We Flying Blind?

BACKGROUND: Two-stage exchange is a commonly used approach for treating chronic periprosthetic joint infections (PJI). A pre-reimplantation threshold value of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) to determine infection eradication and the proper timing of reimplantation remains ill-defined. METHODS: We retrospectively reviewed 483 potential patients for eligibility. In total, 178 patients were excluded. In addition, 305 joints were eligible who underwent 2-stage revision for prosthetic hip or knee joint infection (PJI). Serum ESR and CRP were recorded at 8 weeks post resection prior to stage 2 reimplantation. ESR and CRP were analyzed with receiver operating characteristic curves (ROC) for response failure. RESULTS: In total, 252 patients had resections for chronic infections while 53 septic patients had resections for acute infections. Forty-one of 252 (16.3%) patients failed reimplantation. Median ESR at the time of reimplantation was 17 (normal less than 20 mm/h). Median CRP was 0.6 (normal less than 0.5 mg/dL). ROC plot for response failure in analyzing ESR found an area under the curve (AUC) of 0.47. ROC plot analyzing CRP found an AUC of 0.57. The ratio of ESR/CRP was also utilized and found an AUC of 0.60. All of the AUC data are in the "fail to discriminate category." CONCLUSION: Although improvements in serology can be somewhat reassuring, there are no statistically significant values of ESR or CRP that would predict failure of reimplantation in the 2-stage treatment of PJI. Because we are flying blind consideration should be made for mandatory pre-reimplantation aspirates. LEVEL OF EVIDENCE: Level IV, Retrospective Case Series.

Radiographic and Clinical Outcomes of Modular Tapered Fluted Stems for Femoral Revision for Paprosky III and IV Femoral Defects or Vancouver B2 and B3 Femoral Fractures.

BACKGROUND: Extensive femoral bone loss poses a challenge in revision total hip arthroplasty (rTHA). Many techniques have been developed to address this problem including fully porous cylindrical stems, impaction bone grafting, and cementation of long stems, which have had varied success. Modular tapered fluted femoral stems (MTFS) show favorable results. We sought to determine the minimum 2-year radiographic and clinical performance of MTFS in rTHA in a population with extensive proximal femoral bone loss. METHODS: Our clinical database was queried retrospectively for all patients who underwent rTHA with an MTFS. We included patients with Paprosky 3 and 4 femoral bone loss and patients with Vancouver B2 and B3 periprosthetic femur fractures. Patients without 2-year follow-up were invited to return to clinic for X-ray evaluation and to complete clinical questionnaires. We assessed distance of stem subsidence and presence of stem fixation on final X-ray. We recorded all-cause revision and survival of the stem at final follow-up. RESULTS: One hundred twenty-nine patients were available for follow-up. Average follow-up time was 3.75 years. One hundred twenty-two stems (95%) remained in place at final follow-up. Median subsidence was 1.4 mm (range 0-21). All-cause revision rate was 16.3% (21 patients). Of the hips revised, 10 were for instability, 6 for infection, 1 for aseptic loosening, and 1 for periprosthetic femur fracture. Three were revised for other reasons. The stem was revised in 7 patients (5.4%), and the most common reason for stem revision was infection (5 patients). The other 2 stems were revised for aseptic loosening in a Paprosky 4 femur and periprosthetic femur fracture. Survival of tapered modular fluted stems with aseptic failure as an endpoint was 98.4%. The mean Hip disability and Osteoarthritis Outcome Score, Joint Replacement score at final follow-up was 73, and mean Veterans Rand 12 item health survey physical and mental scores were 32.8 and 52.2, respectively. CONCLUSION: In patients with Paprosky 3, 4 femoral defects or Vancouver type B2, B3 fractures, modular tapered fluted stems for femoral revision show excellent outcomes at minimum 2-year follow-up.

In the Era of Tranexamic Acid, are Type and Screens for Primary Total Joint Arthroplasty Obsolete?

BACKGROUND: Advances in technique and perioperative blood management have improved transfusion rates following unilateral primary total joint arthroplasty and led some centers to change their preoperative blood ordering protocols. The purpose of this study is to determine whether deleting type and screens (T&S) from preoperative order sets was safe for patients undergoing primary total knee (TKA) and total hip arthroplasty (THA) and to identify patients who required allogenic blood transfusion. METHODS: Prospectively collected data were reviewed to identify any patient with a hemoglobin (Hgb) drawn within 30 days of surgery who received a transfusion following a unilateral primary TKA or THA. RESULTS: A total of 1255 patients met inclusion criteria. Of the total, 682 (54%) were TKAs and 573 (46%) were THAs. The mean preoperative Hgb was 11.5 g/dL with an average delta Hgb of 3.6 g/dL on postoperative day 1. No patient required an intraoperative transfusion. Fourteen patients (mean age and body mass index, 67.9 and 29.0) required a transfusion (1.1%) for postoperative blood loss anemia. Of those transfused, 13 (93%) of the patients underwent THA with the mean estimated blood loss of 378.6 mL. The total cost for a patient obtaining a T&S is $191.27. CONCLUSION: In our series, the risk of blood transfusion was rare (1.1%) and occurred only secondary to postoperative blood loss anemia. There were no cases of intraoperative complication requiring urgent or emergent blood transfusion. Removing T&S from standard order sets for patients undergoing primary TKA or THA appears to be a safe and cost-effective practice.

Community-academic partnerships catalyze and sustain impact in research activities: A commentary.

This commentary explores the position that community-academic partnerships (CAPs) can guide collaborative, equitable, and innovative research activities, enhancing knowledge mobilization and overall research impact. We use an example within behavioural sciences (with the broader goal of improving physical literacy development and physical activity for newcomer children and youth) to apply key practices that build bidirectional and trustworthy relationships between researchers, practitioners, and policy-makers, ultimately leading to equity-centered outputs. We report on our experiences both narratively and in video format by interweaving the perspectives of diverse and multi-sectoral team members and describing efforts to continue to engage and drive the momentum of research network activities.

RéSUMé: Ce commentaire explore la position selon laquelle les partenariats communautaires-académiques (PCA) peuvent guider des activités de recherche collaboratives, équitables et innovantes, améliorant la mobilisation des connaissances et l'impact global de la recherche. Nous utilisons un exemple provenant des sciences comportementales (avec l'objectif plus large d'améliorer le développement de la littératie physique et l'activité physique chez les enfants et les jeunes nouvellement arrivés) pour appliquer des pratiques clés qui construisent des relations bidirectionnelles et de confiance entre les chercheurs, les praticiens et les décideurs politiques, conduisant finalement à des résultats centrés sur l'équité. Nous rapportons nos expériences de manière narrative et sous forme vidéo en entrelaçant les perspectives des membres d'équipe diversifiés et multisectoriels. Nous décrivons ainsi les efforts nécessaires pour supporter l'engagement et maintenir l'élan des activités de réseautage.

Arthrotomy Dehiscence After Total Knee Arthroplasty With a Barbed Suture.

INTRODUCTION: Meticulous arthrotomy closure during total knee arthroplasty (TKA) is essential to preserve quadriceps strength and maintain proper patellar tracking. We recently encountered a subset of patients referred with anterior knee pain, a palpable retinaculum defect, and quadriceps weakness. Each patient was found to have an arthrotomy dehiscence. This study highlights arthrotomy dehiscence as a failure mechanism after TKA. METHODS: A retrospective case series of patients who underwent primary TKA followed by subsequent capsular dehiscence was reviewed. We investigated whether the dehiscence was related to trauma, the presence of a palpable arthrotomy defect, patellar tracking, quadriceps strength, and the type of closure technique. RESULTS: All patients had an atraumatic disruption and presented with anterior knee pain and quadriceps weakness. Fourteen of 18 patients (78%) had a palpable defect along the medial retinaculum. Nine of 18 patients (50%) had patellar subluxation or tilting. Barbed sutures were used in 13 of 18 (72%) patients. A simple arthrotomy repair (44%) or a vastus medialis obliquus advancement (56%) was used successfully in all patients. DISCUSSION: Atraumatic arthrotomy dehiscence as a cause of TKA failure historically has been a rare event. Recently, we have noticed a disturbing number of patients presenting with this failure mechanism. With this study, we call attention to this unique atraumatic failure mechanism in patients presenting with anterior knee pain after TKA. Surgeons should be aware of this risk when using barbed sutures alone and should consider routinely reinforcing the arthrotomy with interrupted sutures. LEVEL OF EVIDENCE: Level IV, Retrospective Case Series.

The Influence of Patient Sex on Outcomes Following One-Stage and Two-Stage Revision for Periprosthetic Joint Infection in Total Joint Arthroplasty.

Although females have a higher rate of primary total joint arthroplasty (TJA), males have a higher rate of revision. The literature lacks studies examining the relationship between sex and outcomes following single and two-stage exchange for periprosthetic joint infection (PJI). The purpose of this study was to examine if differences exist in outcomes following revision for chronic PJI between sexes. A retrospective review was performed on all patients with an MSIS confirmed PJI who underwent a single or two-stage exchange at our institution from January 2010 to January 2021. Patient demographics, comorbidity characteristics, and outcomes were collected and compared between males and females. The primary outcome variable was disease-free survival at 1 year following definitive revision. Multivariable logistic regression analysis was performed to determine risk factors for failure. Of the 470 patients meeting final eligibility criteria, 250 were male and 226 were female (2 males and 4 females had a joint infection of either the contralateral side or a different joint and were treated as separate records). Of the patients in the cohort, 80% of the males (200/250) and 80% of the females (181/226) were found to be disease-free at 1-year follow-up (p > 0.99). Multivariable logistic regression analysis showed that nicotine use and diabetes, but not sex, were significant predictors of failure. Our study did not find a relationship between sex and outcome of revision for PJI. Further research is required to determine whether differences exist between males and females in the expression of PJI and outcomes following treatment.

Variability of Sagittal Plane Proximal Tibial Morphology and Its Effect on Stem Placement in Total Knee Arthroplasty.

The tibial joint line is offset posteriorly relative to the tibial sagittal anatomic axis. This can have consequences when using stemmed implants during total knee arthroplasty. We retrospectively analyzed native knee lateral radiographs in 100 patients. The distance between the sagittal anatomic axis and the center of a simulated tibial resection was calculated as a percentage of overall tibial width. Analysis of 5 manufacturers' baseplates showed that the tibial stem attached on average 10% anterior to the midline. We measured the impingement point of a 12-mm-diameter stem starting from this position. The tibial joint surface was offset posteriorly from the anatomic axis in all patients by an average of 23.5% of the tibial width (range: 13.1%-33.2%). A 12-mm tibial stem would impinge within 40 mm in 2% (2/100) of patients and within 60 mm in 19% (19/100). There was a weak but statistically significant correlation between proximal tibial offset and distance to impingement. During total knee arthroplasty, the center of the cut tibia is offset posteriorly from the sagittal anatomic axis. In patients with high offset, tibial stem extensions can impinge against the posterior tibia, causing baseplate malpositioning, diminished cement mantle, or fracture.

Revision total elbow arthroplasty using intramedullary strut allograft for aseptic loosening of the humeral stem.

Total elbow arthroplasty (TEA) has become a well-accepted treatment option for many pathologies of the elbow joint. Its use in distal humerus fractures in elderly patients has become increasingly popular and has good clinical results. However, with the aging population and the increasing number of TEAs performed, so comes the potential for an increasing number of revision TEA cases. Revision TEA can be extremely challenging. In addition to the technical difficulties of safe exposure and implant removal, reimplantation of a cemented humeral component with loss of bone stock can be a challenging step in this procedure. The purpose of this article was to describe a novel technique to address aseptic loosening of the humeral stem and loss of humeral bone stock with revision of the humeral component using a long-stemmed cemented implant and intramedullary allograft fibular strut bone grafting.

Mortality and Conversion Rates to Below-Knee or Above-Knee Amputation After Transmetatarsal Amputation.

INTRODUCTION: The purpose of this study was to identify associated risk factors for complications, need for a higher level of amputation such as below-knee amputation (BKA) or above-knee amputation (AKA), and mortality after transmetatarsal amputation (TMA). METHODS: We identified 265 patients who underwent 286 TMA procedures between June 2002 and July 2016. Medical records were reviewed for revision surgery and amputation. Mortality was verified using the National Death Index. We identified and documented potential risk factors including diabetes, hemoglobin A1c level, end-stage renal disease, cardiovascular disease, peripheral vascular disease, history of revascularization, contralateral amputation, and neuropathy. Sixty-eight percent were male, the mean age was 56.9 years (SD 12.8; range 24.1 to 92.1), and the median body mass index was 28.6 (interquartile range, 24.5 to 33.1). RESULTS: Twenty-seven percent of the patients required a subsequent BKA or AKA after the index TMA surgery. The results of a multivariable model indicated that women (odds ratio [OR], 3.63; 95% confidence interval [CI], 1.716 to 7.672), patients aged 57 to 64 years (OR, 0.17; 95% CI, 0.06 to 0.51), and patients with a history of revascularization (OR, 7.06, 95% CI, 2.86 to 17.44) had markedly higher odds than the relevant comparison groups. Forty percent of the patients died after the index TMA at a median of 27 months. After adjusting for all patient factors, history of end-stage renal disease (OR, 2.2; 95% CI, 1.206 to 4.014) and cardiovascular disease (OR, 2.879; 95% CI, 1.615 to 5.131) remained markedly associated with mortality after TMA. DISCUSSION: There are high rates of additional amputation after nontraumatic TMA and a high mortality rate. Surgeons should set realistic expectations with patients considered for TMA and identify risk factors, which may guide treatment. Treatment is multidisciplinary, requiring attention to surgical details, correction of vascular deficiency or contracture when present, and perioperative medical optimization. LEVEL OF EVIDENCE: IV.

Distal Biceps Repairs in Females: A Large Single-Center Case Series.

Background: Distal biceps repair is a commonly reported procedure in male patients, with reliable outcomes and minimal long-term complications. Information on female patients, however, is limited, and variation in presentation and clinical outcomes is unknown. Questions/Purpose: We sought to report on the presentation, treatment algorithm, and outcomes of a case series of female patients with distal biceps pathology. Methods: A retrospective evaluation was performed from a large, single specialty orthopedic group from 2005 to 2017. Inclusion criteria were surgical treatment of the distal biceps in female patients, with minimum 3 months of follow-up. The primary outcome variable was the Mayo Elbow Performance Score (MEPS). Results: Of 26 patients who met inclusion criteria, 18 (70%) were available for follow-up with patient-reported outcomes. Median age at time of injury was 56.1 years; 46.2% of patients presented with a complete tear of the distal biceps, and the remaining 53.8% presented with a partial tear that failed nonoperative treatment. Six patients had lateral antebrachial cutaneous neuritis in early follow-up, which ultimately resolved. Median MEPS score was 100 (interquartile range: 20). Conclusion: This study represents the largest case series to date describing the presentation, treatment, and outcomes of female patients with distal biceps repair. Women tend to be older than men, have more insidious onset of pain, present with partial tearing, and may benefit from nonoperative treatment. Ultimately, based on this case series we believe distal biceps repair in female patients is a successful operation with minimal complications and high patient satisfaction.

Can an outpatient risk assessment tool predict who needs postoperative haemoglobin monitoring?

AIMS: Recent improvements in surgical technique and perioperative blood management after total joint replacement (TJR) have decreased rates of transfusion. However, as many surgeons transition to outpatient TJR, obtaining routine postoperative blood tests becomes more challenging. Therefore, we sought to determine if a preoperative outpatient assessment tool that stratifies patients based on numerous medical comorbidities could predict who required postoperative haemoglobin (Hb) measurement. METHODS: We performed a prospective study of consecutive unilateral primary total knee arthroplasties (TKAs) and total hip arthroplasties (THAs) performed at a single institution. Prospectively collected data included preoperative and postoperative Hb levels, need for blood transfusion, length of hospital stay, and Outpatient Arthroplasty Risk Assessment (OARA) score. RESULTS: A total of 504 patients met inclusion criteria. Mean age at time of arthroplasty was 65.3 years (SD 10.2). Of the patients, 216 (42.9%) were THAs and 288 (57.1%) were TKAs. Six patients required a blood transfusion postoperatively (1.19%). Transfusion after surgery was associated with lower postoperative day 1 Hb (median of 8.5 (interquartile range (IQR) 7.9 to 8.6) vs 11.3 (IQR 10.4 to 12.2); p < 0.001), longer length of stay (1 day (IQR 1 to 1) vs 2 days (IQR 2 to 3); p < 0.001), higher OARA score (median of 60.0 (IQR 40 to 75) vs 5.0 (IQR 0-35); p = 0.001), and total hip arthroplasty (p < 0.001). All patients who received a transfusion had an OARA score > 34; however, this did not reach statistical significance as a screening threshold. CONCLUSION: Risk of blood transfusion after primary TJR was uncommon in our series, with an incidence of 1.19%. Transfusion was associated with OARA scores > 60. The OARA score, not American Society of Anesthesiologists grade, reliably identified patients at risk for postoperative blood transfusion. Selective Hb monitoring may result in substantial cost savings in the era of cost containment. Cite this article: Bone Joint J 2021;103-B(1):65-70.