We reviewed 194 revision arthroplasties of the hip and knee performed over a ten-year period. The results of intraoperative Gram
Specific antisera to collagen Types I, II and III and proteoglycan were used to investigate the distributions of these molecules in normal human intervertebral discs. Immunofluorescent
Aims. The aim of this study was to determine the rate of indocyanine green (ICG)
Aims. This study aimed to answer two questions: what are the best diagnostic methods for diagnosing bacterial arthritis of a native joint?; and what are the most commonly used definitions for bacterial arthritis of a native joint?. Methods. We performed a search of PubMed, Embase, and Cochrane libraries for relevant studies published between January 1980 and April 2020. Of 3,209 identified studies, we included 27 after full screening. Sensitivity, specificity, area under the curve, and Youden index of diagnostic tests were extracted from included studies. We grouped test characteristics per diagnostic modality. We extracted the definitions used to establish a definitive diagnosis of bacterial arthritis of a native joint per study. Results. Overall, 28 unique diagnostic tests for diagnosing bacterial arthritis of a native joint were identified. The following five tests were deemed most useful: serum ESR (sensitivity: 34% to 100%, specificity: 23% to 93%), serum CRP (sensitivity: 58% to 100%, specificity: 0% to 96%), serum procalcitonin (sensitivity: 0% to 100%, specificity: 68% to 100%), the proportion of synovial polymorphonuclear cells (sensitivity: 42% to 100%, specificity: 54% to 94%), and the gram
Aims. Fungal and mycobacterial periprosthetic joint infections (PJI) are rare events. Clinicians are wary of missing these diagnoses, often leading to the routine ordering of fungal and mycobacterial cultures on periprosthetic specimens. Our goal was to examine the utility of these cultures and explore a modern bacterial culture technique using bacterial blood culture bottles (BCBs) as an alternative. Methods. We performed a retrospective review of patients diagnosed with hip or knee PJI between 1 January 2010 and 31 December 2019, at the Mayo Clinic in Rochester, Minnesota, USA. We included patients aged 18 years or older who had fungal, mycobacterial, or both cultures performed together with bacterial cultures. Cases with positive fungal or mycobacterial cultures were reviewed using the electronic medical record to classify the microbiological findings as representing true infection or not. Results. There were 2,067 episodes of PJI diagnosed within the study period. A total of 3,629 fungal cultures and 2,923 mycobacterial cultures were performed, with at least one of these performed in 56% of episodes (n = 1,157). Test positivity rates of fungal and mycobacterial cultures were 5% (n = 179) and 1.2% (n = 34), respectively. After a comprehensive review, there were 40 true fungal and eight true mycobacterial PJIs. BCB were 90% sensitive in diagnosing true fungal PJI and 100% sensitive in detecting rapidly growing mycobacteria (RGM). Fungal
Aim. Mesenchymal stem cells (MSCs) have several properties that may support their use as an early treatment option for osteoarthritis (OA). This study investigated the role of multiple injections of allogeneic bone marrow-derived stem cells (BMSCs) to alleviate the progression of osteoarthritic changes in the various structures of the mature rabbit knee in an anterior cruciate ligament (ACL)-deficient OA model. Materials and Methods. Two months after bilateral section of the ACL of Japanese white rabbits aged nine months or more, either phosphate buffered saline (PBS) or 1 x 10. 6. MSCs were injected into the knee joint in single or three consecutive doses. After two months, the articular cartilage and meniscus were assessed macroscopically, histologically, and immunohistochemically using collagen I and II. Results. Within the PBS injection (control group), typical progressive degenerative changes were revealed in the various knee structures. In the single MSC injection (single group), osteoarthritic changes were attenuated, but still appeared, especially in the medial compartments involving fibrillation of the articular cartilage, osteophyte formation in the medial plateau, and longitudinal tear of the meniscus. In the multiple-injections group, the smoothness and texture of the articular cartilage and meniscus were improved. Histologically, absence or reduction in matrix
Aims. To investigate metallosis in patients with magnetically controlled growing rods (MCGRs) and characterize the metal particle profile of the tissues surrounding the rod. Methods. This was a prospective observational study of patients with early onset scoliosis (EOS) treated with MCGRs and undergoing rod exchange who were consecutively recruited between February 2019 and January 2020. Ten patients were recruited (mean age 12 years (SD 1.3); 2 M:8 F). The configurations of the MCGR were studied to reveal the distraction mechanisms, with crucial rod parts being the distractable piston rod and the magnetically driven rotor inside the barrel of the MCGR. Metal-on-metal contact in the form of ring-like wear marks on the piston was found on the distracted portion of the piston immediately outside the barrel opening (BO) through which the piston rod distracts. Biopsies of paraspinal muscles and control tissue samples were taken over and away from the wear marks, respectively. Spectral analyses of the rod alloy and biopsies were performed to reveal the metal constituents and concentrations. Histological analyses of the biopsies were performed with haematoxylin and eosin
Aims. The aim of this study was to conduct the largest low contact stress (LCS) retrieval study to elucidate the failure mechanisms of the Porocoat and Duofix femoral component. The latter design was voluntarily recalled by the manufacturer. Materials and Methods. Uncemented LCS explants were divided into three groups: Duofix, Porocoat, and mixed. Demographics, polyethylene wear, tissue ingrowth, and metallurgical analyses were performed. Results. In 104 implants, a decrease in the odds of loosening and an increase in metallosis and tissue
Bovine and human articular chondrocytes were seeded in 2% alginate constructs and cultured for up to 19 days in a rotating-wall-vessel (RWV) and under static conditions. Culture within the RWV enhanced DNA levels for bovine chondrocyte-seeded constructs when compared with static conditions but did not produce enhancement for human cells. There was a significant enhancement of glycosaminoglycans and hydroxyproline synthesis for both bovine and human chondrocytes. In all cases, histological analysis revealed enhanced Safranin-O
Aims. It is increasingly appreciated that coordinated regulation of angiogenesis and osteogenesis is needed for bone formation. How this regulation is achieved during peri-implant bone healing, such as osseointegration, is largely unclear. This study examined the relationship between angiogenesis and osteogenesis in a unique model of osseointegration of a mouse tibial implant by pharmacologically blocking the vascular endothelial growth factor (VEGF) pathway. Materials and Methods. An implant was inserted into the right tibia of 16-week-old female C57BL/6 mice (n = 38). Mice received anti-VEGF receptor-1 (VEGFR-1) antibody (25 mg/kg) and VEGF receptor-2 (VEGFR-2) antibody (25 mg/kg; n = 19) or an isotype control antibody (n = 19). Flow cytometric (n = 4/group) and immunofluorescent (n = 3/group) analyses were performed at two weeks post-implantation to detect the distribution and density of CD31. hi. EMCN. hi. endothelium. RNA sequencing analysis was performed using sorted CD31. hi. EMCN. hi. endothelial cells (n = 2/group). Osteoblast lineage cells expressing osterix (OSX) and osteopontin (OPN) were also detected with immunofluorescence. Mechanical pull-out testing (n = 12/group) was used at four weeks post-implantation to determine the strength of the bone-implant interface. After pull-out testing, the tissue attached to the implant surface was harvested. Whole mount immunofluorescent
We attempted to repair full-thickness defects in the articular cartilage of the trochlear groove of the femur in 30 rabbit knee joints using allogenic cultured chondrocytes embedded in a collagen gel. The repaired tissues were examined at 2, 4, 8, 12 and 24 weeks after operation using histological and histochemical methods. The articular defect filling index measurement was derived from safranin-O
Aims. Leucocyte esterase (LE) has been shown to be an accurate marker of prosthetic joint infection (PJI), and has been proposed as an alternative to frozen section (FS) histology for intraoperative diagnosis. In this study, the intraoperative assessment of LE was compared with FS histology for the diagnosis of prosthetic hip infection. Patients and Methods. A total of 119 patients undergoing revision total hip arthroplasty (THA) between June 2015 and December 2017 were included in the study. There were 56 men and 63 women with a mean age of 66.2 years (27 to 88). Synovial fluid was collected before arthrotomy for the assessment of LE using enzymatic colourimetric strips. Between five and six samples were
The aim of this study was to evaluate the optimal deep tissue specimen sample number for histopathological analysis in the diagnosis of periprosthetic joint infection (PJI). In this retrospective diagnostic study, patients undergoing revision surgery after total hip or knee arthroplasty (n = 119) between January 2015 and July 2018 were included. Multiple specimens of the periprosthetic membrane and pseudocapsule were obtained for histopathological analysis at revision arthroplasty. Based on the Infectious Diseases Society of America (IDSA) 2013 criteria, the International Consensus Meeting (ICM) 2018 criteria, and the European Bone and Joint Infection Society (EBJIS) 2021 criteria, PJI was defined. Using a mixed effects logistic regression model, the sensitivity and specificity of the histological diagnosis were calculated. The optimal number of periprosthetic tissue specimens for histopathological analysis was determined by applying the Youden index.Aims
Methods
We hypothesised that cells obtained via a Reamer–Irrigator–Aspirator
(RIA) system retain substantial osteogenic potential and are at
least equivalent to graft harvested from the iliac crest. Graft
was harvested using the RIA in 25 patients (mean age 37.6 years
(18 to 68)) and from the iliac crest in 21 patients (mean age 44.6
years (24 to 78)), after which ≥ 1 g of bony particulate graft material
was processed from each. Initial cell viability was assessed using Trypan
blue exclusion, and initial fluorescence-activated cell sorting
(FACS) analysis for cell lineage was performed. After culturing
the cells, repeat FACS analysis for cell lineage was performed and
enzyme-linked immunosorbent assay (ELISA) for osteocalcin, and Alizarin
red
Bacterial infection activates neutrophils to release neutrophil extracellular traps (NETs) in bacterial biofilms of periprosthetic joint infections (PJIs). The aim of this study was to evaluate the increase in NET activation and release (NETosis) and haemostasis markers in the plasma of patients with PJI, to evaluate whether such plasma induces the activation of neutrophils, to ascertain whether increased NETosis is also mediated by reduced DNaseI activity, to explore novel therapeutic interventions for NETosis in PJI in vitro, and to evaluate the potential diagnostic use of these markers. We prospectively recruited 107 patients in the preoperative period of prosthetic surgery, 71 with a suspicion of PJI and 36 who underwent arthroplasty for non-septic indications as controls, and obtained citrated plasma. PJI was confirmed in 50 patients. We measured NET markers, inflammation markers, DNaseI activity, haemostatic markers, and the thrombin generation test (TGT). We analyzed the ability of plasma from confirmed PJI and controls to induce NETosis and to degrade in vitro-generated NETs, and explored the therapeutic restoration of the impairment to degrade NETs of PJI plasma with recombinant human DNaseI. Finally, we assessed the contribution of these markers to the diagnosis of PJI.Aims
Methods
Implantation of ultra-purified alginate (UPAL) gel is safe and effective in animal osteochondral defect models. This study aimed to examine the applicability of UPAL gel implantation to acellular therapy in humans with cartilage injury. A total of 12 patients (12 knees) with symptomatic, post-traumatic, full-thickness cartilage lesions (1.0 to 4.0 cm2) were included in this study. UPAL gel was implanted into chondral defects after performing bone marrow stimulation technique, and assessed for up to three years postoperatively. The primary outcomes were the feasibility and safety of the procedure. The secondary outcomes were self-assessed clinical scores, arthroscopic scores, tissue biopsies, and MRI-based estimations.Aims
Methods
Low-grade central osteosarcoma (LGCOS), a rare type of osteosarcoma, often has misleading radiological and pathological features that overlap with those of other bone tumours, thereby complicating diagnosis and treatment. We aimed to analyze the clinical, radiological, and pathological features of patients with LGCOS, with a focus on diagnosis, treatment, and outcomes. We retrospectively analyzed the medical records of 49 patients with LGCOS (Broder’s grade 1 to 2) treated between January 1985 and December 2017 in a single institute. We examined the presence of malignant features on imaging (periosteal reaction, cortical destruction, soft-tissue invasion), the diagnostic accuracy of biopsy, surgical treatment, and oncological outcome.Aims
Methods
Histology is widely used for diagnosis of persistent infection during reimplantation in two-stage revision hip and knee arthroplasty, although data on its utility remain scarce. Therefore, this study aims to assess the predictive value of permanent sections at reimplantation in relation to reinfection risk, and to compare results of permanent and frozen sections. We retrospectively collected data from 226 patients (90 hips, 136 knees) with periprosthetic joint infection who underwent two-stage revision between August 2011 and September 2021, with a minimum follow-up of one year. Histology was assessed via the SLIM classification. First, we analyzed whether patients with positive permanent sections at reimplantation had higher reinfection rates than patients with negative histology. Further, we compared permanent and frozen section results, and assessed the influence of anatomical regions (knee versus hip), low- versus high-grade infections, as well as first revision versus multiple prior revisions on the histological result at reimplantation. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), chi-squared tests, and Kaplan-Meier estimates were calculated.Aims
Methods
The preoperative grading of chondrosarcomas of bone that accurately predicts surgical management is difficult for surgeons, radiologists, and pathologists. There are often discrepancies in grade between the initial biopsy and the final histology. Recent advances in the use of imaging methods have shown promise in the ability to predict the final grade. The most important clinical distinction is between grade 1 chondrosarcomas, which are amenable to curettage, and resection-grade chondrosarcomas (grade 2 and 3) which require en bloc resection. The aim of this study was to evaluate the use of a Radiological Aggressiveness Score (RAS) to predict the grade of primary chondrosarcomas in long bones and thus to guide management. A total of 113 patients with a primary chondrosarcoma of a long bone presenting between January 2001 and December 2021 were identified on retrospective review of a single oncology centre’s prospectively collected database. The nine-parameter RAS included variables from radiographs and MRI scans. The best cut-off of parameters to predict the final grade of chondrosarcoma after resection was determined using a receiver operating characteristic curve (ROC), and this was correlated with the biopsy grade.Aims
Methods