The lateral approach for total knee arthroplasty in valgus osteoarthritis provides similar clinical and radiological results compared with the medial approach.

PURPOSE: In total knee arthroplasty (TKA), valgus deformities require special approaches to achieve precise mechanical axis correction and joint stability. This study aimed to determine whether the lateral approach without tibial tubercle osteotomy allows mechanical axis correction in valgus knee osteoarthritis (OA), which is at least as effective as the medial approach, while also assessing whether it provides clinically comparable results and complications. METHODS: A total of 204 patients undergoing TKA for valgus knee OA were included in this retrospective comparative study, with 131 patients in the lateral approach group and 73 patients in the medial approach group. The surgical goal was to achieve stability with a neutral axis based on mechanical alignment. Detailed pre- and postoperative clinical and radiographic data were obtained, including measurements of the hip-knee-ankle angle (HKAA) and patella tilt angle. Functional status was determined based on the Oxford Knee Score (OKS). Age, body mass index, sex and preoperative HKAA were adjusted between both groups using propensity score matching (n = 45 per group). RESULTS: In the propensity score-matched cohort, the postoperative HKAA did not show differences when comparing the lateral and the medial approach at a mean follow-up of 19.7 months (p = 0.385). The achieved correction of the patella tilt angle was higher in the lateral approach group in the overall (p < 0.001) and matched cohort (p < 0.001). No differences were detected regarding the postoperative OKS and complications. However, wound healing disorders showed a tendency to be more prevalent in patients who underwent the lateral approach in the overall cohort (6.1%, n = 8 vs. 0.0%, n = 0, p = 0.053) but not in the propensity score-matched cohort (p = 0.494). CONCLUSION: This study demonstrated that for pronounced valgus OA, the lateral approach achieves favourable results in HKAA correction, patellar tilt and complications comparable to the medial approach. However, the risk of wound healing disorders appears higher with severe valgus deformity. LEVEL OF EVIDENCE: Level III therapeutic study.

Clinical evaluation of a new technique for custom-made spacers in septic two-stage revision of total hip arthroplasties.

INTRODUCTION: In septic two-stage revision surgery, success depends on numerous factors. Key steps are the procedure of ex- and reimplantation and the choice of spacer in the interim phase. The latter is still a matter of debate. Recently, we showed the microbial non-inferiority of a spacer technique using prosthetic cemented implants with an individualized antibiotic mixture in the cement applying a mechanically inferior cementation method. The aim of the present study was to evaluate the clinical results of these spacers in view of either an endofemoral or a transfemoral procedure. MATERIALS AND METHODS: Our collective consisted of 86 patients (45 endofemoral and 41 transfemoral procedures). The collective was analyzed with respect to complications, reinfection rate and clinical status at the end of the interim phase. Results of an endofemoral and transfemoral approach were compared. RESULTS: With a median Staffelstein-Score of 60 (range 31-81) at the end of the interim phase, the first clinical results are promising. The reinfection-free rate after a median follow-up of 50 months was 90%. Spacer-related complications occurred in 8% of the total collective. Comparing the endo- and transfemoral procedure, there were no statistical differences in complications or regarding the clinical and infectiological outcome. CONCLUSIONS: In this study, we were able to show good clinical results for the presented spacer technique. With no relevant difference in outcome, the decision for an endofemoral or transfemoral technique can be based on technical deliberations. Further prospective comparative studies are necessary to show the clinical benefit of this procedure.

Reconstruction of the anatomy of the hip in total hip arthroplasty with two different kinds of stems.

BACKGROUND: The reconstruction of the individual anatomy is important in total hip replacement. The aim of the study was to compare two different kinds of stems with respect to the reconstruction of the individual anatomy of the hip. METHODS: We compared the restoration of the anatomical parameters (horizontal and vertical offset, femoral neck-shaft angle (NSA) and leg length) of 100 unilateral CoreHip (CH) implantations with 100 unilateral implantations of a standard anatomical stem (Exception (E)). The CoreHip has three different NSAs and exhibits a constant femoral neck length for the different sizes. The Exception stem has a standard and lateralized version with two different NSAs and, in both versions, the femoral neck length increases proportionately with size. The anatomical parameters of the operated and healthy sides were measured and the differences between the two stems compared. RESULTS: The horizontal (2.5 ± 2.8 mm (mean ± SD) for CH vs. 5.4 ± 4.1 mm for E, p < 0.001) and vertical offset (4.1 ± 3.5 mm for CH vs. 5.0 ± 3.8 mm, p = 0.024) and femoral neck-shaft-angle (1.7 ± 1.6 degrees for CH vs. 5.6 ± 3.4 degrees for E, p < 0.001) could be reconstructed significantly better with the CoreHip system. There was a tendency for the leg length (4.0 ± 3.9 mm for CH vs. 4.5 ± 3.8 mm; p = 0.11) to be better restored with the CoreHip. CONCLUSION: The reconstruction of the individual anatomy of the hip with an endoprosthesis could be realized significantly better with the stem that was designed with three different femoral neck-shaft angles and a constant femoral neck length over different sizes.

The significance of synovial biopsy in the diagnostic workup of the low-grade periprosthetic joint infection of shoulder arthroplasty.

INTRODUCTION: A common reason for painful shoulder arthroplasties and revision surgery is a low-grade periprosthetic joint infection (PJI). Diagnosing a low-grade infection is, however, a major diagnostic challenge. This applies even more to the shoulder, which differs from other large joints in terms of clinical features and microbiological spectrum. Aim of this study was to evaluate the diagnostic value of the synovial biopsy in the diagnostic workup of low-grade PJI of the shoulder. MATERIALS AND METHODS: A retrospective evaluation was conducted on 56 patients receiving revision surgery on their shoulder arthroplasty. A standardized preoperative workup was performed comprising CRP value, leukocyte blood count, synovial fluid microbiological analyses and leukocyte count from joint aspiration, and five synovial biopsy samples for bacteriologic and histologic analysis obtained through an arthroscopic approach. During revision surgery, five samples of periprosthetic tissue were harvested for bacteriologic and histologic analyses. The MSIS-Criteria 2014 were used to evaluate the diagnostic results. RESULTS: In total, 15 of 56 revised prostheses turned out as PJI (27%). When applying our diagnostic workup, we obtained a sensitivity of 67% with a specificity of 95%. When performing a subgroup analysis on those patients that had received diagnostic biopsy, a sensitivity of 100% and a specificity of 83% could be achieved. With a sensitivity and specificity of 90% and 83%, respectively, the biopsy is the single method with the highest diagnostic value. CONCLUSIONS: The sensitivity of only 67% of our standard workup emphasizes the difficulty to adequately diagnose low-grade infections after shoulder arthroplasty. The excellent specificity of 95% ensures, however, that non-infected prostheses are not incorrectly explanted. This study highlights that synovial biopsy has a high diagnostic value and should be done prior to complex revision surgeries to raise sensitivity in diagnosing a PJI.

Prior high tibial osteotomy is not a contraindication for medial unicompartmental knee arthroplasty.

PURPOSE: To report on the outcome and complications of minimal invasive medial unicondylar knee arthroplasty (UKA) after failed prior high tibial osteotomy (HTO) as treatment for medial osteoarthritis in the knee. The hypothesis was that good results can be achieved, if no excessive postoperative valgus alignment and abnormal proximal tibial geometry is present. METHODS: All medial UKAs after failed prior HTO (n = 30), performed between 2010 and 2018 were retrospectively reviewed. The patients were followed for revision surgery and survival of the UKA (defined as revision to TKA). Clinical examination using the Knee Society Score (KSS), Oxford Knee Score (OKS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), as well as radiological examination was performed. Radiographs were studied and the influence of the demographic factors and the radiographic measurements on the survival and the clinical outcome was analysed. RESULTS: After a follow-up of 4.3 ± 2.6 years (2.1-9.9) 27 UKAs were available. The survival rate was 93.0%. Two UKAs were revised to TKA (excessive valgus alignment and tibial loosening with femoropatellar degeneration). Two further patients had revision surgery (hematoma and lateral meniscus tear). Follow-up clinical and radiological examination was performed in 21 cases: KSS 82.9 ± 10.1 (54.0-100.0), KSS (function) 93.3 ± 9.7 (70.0-100.0); OKS 42.7 ± 6.0 (25.0-48.0); WOMAC 7.9 ± 15.6 (0.0-67.1). No significant influence of demographic factors or radiological measurements on the clinical outcome was present. CONCLUSION: Prior HTO is not a contraindication for medial UKA, because good-to-excellent results can be achieved in selected patients with medial osteoarthritis and previous HTO, treated with medial UKA, in a midterm follow-up. Excessive mechanical valgus axis should be avoided; therefore, patient selection and accurate evaluation of medial laxity, preoperative mechanical axis, joint line convergence and proximal tibial geometry are important. LEVEL OF EVIDENCE: III.

Antibiotic therapy alone does not have a high success rate in cases of unexpected positive cultures in intraoperative samples from hip and knee prosthesis revision.

BACKGROUND: Unexpectedly positive bacterial cultures during prosthesis revision surgery still occur on occasion despite good preoperative diagnostics. In such cases a six-week antibiotic therapy without further surgical intervention is recommended. The aim of this study was to find out how successful this procedure is. METHODS: In a study of 508 patients, who required revision surgery of total hip (THA, n = 231) or knee arthroplasties (TKA, n = 277) because of component loosening, biopsy was carried out before their surgery. The collected tissue samples (5) from the biopsy and the revision surgery procedure itself were analyzed according the criteria of the International Consensus Meeting (ICM). Tests revealed 11 patients (7 THA, 4 TKA) with unexpectedly positive bacterial cultures from tissue samples obtained during the revision surgery due to false negative preoperative diagnostic results. These 11 patients were treated with 6 weeks antibiotic therapy and examined with a follow-up of at least 2 years (42.2 ± 16.5 months). RESULTS: Five patients (2 TKA, 3 THA) became reinfected, resulting in a success rate of 54.5%. CONCLUSION: Antibiotic therapy alone of an unexpected positive intraoperative bacterial culture in prosthesis revision surgery seems to be less successful than previously assumed.

C-reactive protein is not a screening tool for late periprosthetic joint infection.

BACKGROUND: Preoperative diagnosis of periprosthetic joint infection (PJI) is important because of the therapeutic consequences. The aim of the present study is to investigate whether the serum C-reactive protein (CRP) level can be used as a screening tool for late PJI. MATERIALS AND METHODS: A cohort of 390 patients with revision surgery of total hip prostheses (200) or total knee prostheses (190) was assessed for late PJI by determining CRP serum level and performing preoperative aspiration with cultivation and intraoperative tissue analyses with cultivation and histologic examination, using the Musculoskeletal Infection Society (MSIS) and International Consensus Meeting (ICM) criteria. RESULTS: A total of 180 joints were rated as PJI (prevalence 46%). Of these, 42.8% (77) showed a CRP level below 10 mg/L and 28.3% (51) showed a normal CRP level of less than 5 mg/L. The 76.9% of the cases with slow-growing bacteria showed a CRP level below 10 mg/L, and 61.5% showed a normal CRP level. CONCLUSIONS: Serum CRP level should not be used as a screening tool to rule out late PJI. LEVEL OF EVIDENCE: Level 2 (diagnostic study).

Fixation of a modular curved revision stem with a taper of 2° in the femur.

INTRODUCTION: Modular revision stems with a short distal component can prevent the bypassing of the femoral isthmus and hereby theoretically have advantages concerning risk of periprosthetic fractures, breakage of the junction and a technically easier revision procedure. MATERIALS AND METHODS: Radiological evaluation of 202 stem revision operations with the modular curved revision stem "Revitan Curved" with a 2° taper was carried out after a mean follow-up period of 7.44 ± 2.09 years (3-13 years) to investigate whether short-stem combinations are effective in Paprosky 2 and 3A defects with respect to rate of subsidence and loosening. RESULTS: Sixty of 62 endofemoral (96.8%) and 137 of 140 transfemoral implantations (97.9%) involved the short, 140 mm distal component. Significant subsidence was seen in 3.3% of cases following endofemoral implantation and in 2.1% of cases following transfemoral implantation. Neither aseptic loosening nor periprosthetic fracture were observed. CONCLUSION: The use of combinations of short modular components leads to reproducibly good outcomes in femoral revision with respect to subsidence and loosening.

One-stage exchange of septic shoulder arthroplasty following a standardized treatment algorithm.

BACKGROUND: Studies on 1-stage exchange in septic shoulder arthroplasty are limited and show a wide variation of treatment strategies. This retrospective study investigated infection-free survival and function of 1-stage exchange of septic shoulder arthroplasty following a standardized treatment algorithm. METHODS: The requirement for 1-stage exchange was an isolated microorganism from synovial fluid aspiration or synovial biopsy with an antibiotic susceptibility profile prior to revision surgery. If no microorganism was isolated or the underlying pathogen was a difficult-to-treat microorganism (not accessible for biofilm-active antibiotics, enterococci, and fungi), 2-stage exchange was performed. Function was assessed by the Constant score. RESULTS: Fourteen patients were included, with a mean follow-up period of 5.8 years. The most and second most commonly detected microorganisms were Cutibacterium acnes (formerly Propionibacterium acnes), and Staphylococcus epidermidis, respectively. At 1-stage exchange, patients received local and systemic antibiotics based on the susceptibility profile of the microorganism. Twelve patients with insufficient rotator cuffs received reverse shoulder arthroplasty, whereas 2 patients with intact rotator cuffs underwent anatomic total shoulder arthroplasty. The infection-free survival rate at 1 and 5 years was 100% and 93% (95% confidence interval [CI], 59%-99%), respectively, with 1 recurrence of infection 22 months after 1-stage exchange. Another patient with limited range of motion underwent revision 6 months postoperatively, leading to a revision-free survival rate of 93% (95% CI, 59%-99%) and 86% (95% CI, 54%-96%) at 1 and 5 years, respectively. The mean Constant score was 65 (range, 44-95). CONCLUSION: One-stage exchange with prior detection of the underlying microorganism provides satisfactory infection-free survival and function.

Treatment of Extensive Gluteus Muscle Tears With Transosseous Fixation and a Nonresorbable Collagen Patch.

BACKGROUND: Extensive tearing of the gluteus muscles (spontaneous or subsequent to hip arthroplasty) is difficult to treat. We are carrying out osseous fixation with securement of the suture anchor by a nonresorbable collagen patch. The objective of this study is to examine the follow-up data of 30 patients and to assess whether the clinical outcomes depended on the extent of the fatty degeneration of the gluteus medius. METHODS: Thirty patients (28 female and 2 male) with a mean age of 76.8 ± 4.3 years (68-83 years) were followed for a mean of 46.8 ± 23.1 months (24-101 months). RESULTS: Pain improved significantly from a preoperative visual analog scale score of 7.0 ± 1.52 (6-10) to 0.83 ± 0.77 (0-3) 24-month postoperative. The gluteus medius muscle force increased from 2.09 ± 0.81 to 3.3 ± 0.78 using the British Medical Research Council Scale. All patients exhibited a severe limp before the operation. Postoperatively, only 5 patients had a severe limp, while 14 exhibited a mild limp and 11 no limp at all. The modified Harris Hip Score increased from a preoperative value of 44.5 ± 4.2 (26-66) to a value of 81.1 ± 7.79 (60-100) 24-month postoperative. The functional results were dependent on the level of fatty degeneration of the muscle. CONCLUSION: The first results for this surgical technique appear to be very promising for the treatment of extensive tearing of the gluteus musculature that has a degree of fatty degeneration less than 75%.

Preoperative PCR analysis of synovial fluid has limited value for the diagnosis of periprosthetic joint infections of total knee arthroplasties.

Preoperative diagnosis of periprosthetic joint infection (PJI) is important because of the therapeutic consequences. This prospective study was designed to answer the question, if preoperative PCR analysis of the synovial fluid in addition to the culture and the CRP analysis of the blood are helpful for the diagnosis of PJI in knee arthroplasties. Before revision CRP analysis of the blood, cultivation and PCR analysis of synovial fluid of 116 knee endoprostheses were performed. During revision surgery, five tissue samples of the periprosthetic tissue were cultured and five further samples subjected to histological analysis. These analyses of the periprosthetic tissue were used to verify the results of the preoperative diagnostic methods. Twenty-seven prostheses were identified as infected (prevalence 23.3%). The combined analyses of the joint fluid cultivation and the CRP blood level resulted in a sensitivity of 77.8%, a specificity of 95.5%, a positive-predictive value of 84.0%, a negative-predictive value of 93.4% and an accuracy of 91.4%. The PCR analysis of the synovial fluid resulted in a sensitivity of 55.6%, a specificity of 82.0%, a positive-predictive value of 48.4%, a negative-predictive value of 85.9% and an accuracy of 75.9%. The sensitivity for culture of the aspirate and PCR analysis in combination with an elevated CRP level was 85.2%, the specificity 82.0%, the positive-predictive value 58.9%, the negative-predictive value 94.8% and the accuracy 82.7%. The preoperative PCR analysis of synovial fluid has only limited value in addition to the standard culture analysis.

Single-stage Acetabular Revision During Two-stage THA Revision for Infection is Effective in Selected Patients.

BACKGROUND: The treatment of periprosthetic infections of hip arthroplasties typically involves use of either a single- or two-stage (with implantation of a temporary spacer) revision surgery. In patients with severe acetabular bone deficiencies, either already present or after component removal, spacers cannot be safely implanted. In such hips where it is impossible to use spacers and yet a two-stage revision of the prosthetic stem is recommended, we have combined a two-stage revision of the stem with a single revision of the cup. To our knowledge, this approach has not been reported before. QUESTIONS/PURPOSES: (1) What proportion of patients treated with single-stage acetabular reconstruction as part of a two-stage revision for an infected THA remain free from infection at 2 or more years? (2) What are the Harris hip scores after the first stage and at 2 years or more after the definitive reimplantation? METHODS: Between June 2009 and June 2014, we treated all patients undergoing surgical treatment for an infected THA using a single-stage acetabular revision as part of a two-stage THA exchange if the acetabular defect classification was Paprosky Types 2B, 2C, 3A, 3B, or pelvic discontinuity and a two-stage procedure was preferred for the femur. The procedure included removal of all components, joint débridement, definitive acetabular reconstruction (with a cage to bridge the defect, and a cemented socket), and a temporary cemented femoral component at the first stage; the second stage consisted of repeat joint and femoral débridement and exchange of the femoral component to a cementless device. During the period noted, 35 patients met those definitions and were treated with this approach. No patients were lost to followup before 2 years; mean followup was 42 months (range, 24-84 months). The clinical evaluation was performed with the Harris hip scores and resolution of infection was assessed by the absence of clinical signs of infection and a C-reactive protein level less than 10 mg/L. All patients were assessed before surgery, between stages, every 3 months during the first year after surgery, every 6 months during the second year postoperative, and at latest followup, and were retrospectively drawn from a longitudinally maintained institutional database. RESULTS: Thirty-four of 35 patients (97.2%; 95% CI, 85.4%-99.5%) appeared free of infection by criteria of Masri et al. and Zimmerli et al. at latest followup. The Harris hip score was 61 ± 13 points after the first operation and 82 ± 16 points 2 years after the second operation. CONCLUSIONS: This technique is a promising treatment option for periprosthetic infections of the hip in which substantial acetabular defects exclude implantation of a normal spacer and a two-stage revision of the femoral component is favored. LEVEL OF EVIDENCE: Level IV, therapeutic study.

A Standardized Regimen for the Treatment of Acute Postoperative Infections and Acute Hematogenous Infections Associated With Hip and Knee Arthroplasties.

BACKGROUND: Papers concerning the treatment of periprosthetic infections and acute hematogenous infections often concern inhomogeneous treatment concepts or low numbers of patients; this results in inconsistent rates of treatment success. METHODS: Thirty-nine patients with early periprosthetic infections and 28 patients with acute hematogenous infections were treated with a homogeneous concept and followed with a mean period of 41.8 (24-132) months in order to investigate the success rate and influencing factors. All patients were treated with open surgical debridement, a revision of all removable components and irrigation with an antiseptic solution (octinedine). All patients received a systemic vancomycin/rifampicin antibiotic therapy until the microorganism causing the infection could be identified; a specific antibiotic therapy then followed until the end of the sixth week. RESULTS: This unified treatment regimen resulted in an overall success rate of 71.6%, an 82.1% success for early infections and 57.1% for acute hematogenous infections. Variables that influenced the recurrence of an infection were the timespan between revision and first appearance of symptoms (<2 days), the number of previous operations, the American Society of Anesthesiologists classification, and nicotine abuse. CONCLUSION: It appears that, in cases of early postoperative infection, a reproducibly high rate of success in retaining an implant can be achieved with this specific therapy regime if surgical intervention can be carried out within 2 days of first symptoms.

A comparison of apixaban and dabigatran etexilate for thromboprophylaxis following hip and knee replacement surgery.

INTRODUCTION: Patients who have undergone hip or knee replacement surgery are exposed to a high risk of developing a post-operative venous thromboembolus and so have a need for an effective, medication-based, thrombosis prophylaxis. New orally active anticoagulants have been available for a few years now. These specific substances directly block either thrombin (e.g., dabigatran etexilate) or Factor Xa (e.g., apixaban). It is not clear whether there are any efficacy differences between these two substances because there have never been any head-to-head studies carried out. MATERIALS AND METHODS: We have carried out a study comparing two new orally active anticoagulants dabigatran etexilate (Pradaxa®) and apixaban (Eliquis®) that were each given to two groups of 200 patients respectively, who had undergone elective hip or knee arthroplasty (100 each). Each patient was assessed for pre- and post-operative hemoglobin concentrations, post-operative blood loss, the number of transfused erythrocyte concentrates, the duration of wound secretion, clinical thromboembolic complications (deep vein thrombosis, pulmonary embolism, myocardial infarct), as well as gastrointestinal, intracranial or wound-related bleeding complications. RESULTS: Dabigatran etexilate treatment led to a significant increase in the duration of wound secretion in both arthroplasty groups when compared to apixaban: wound secretion lasted 1.2 days longer on average in the dabigatran etexilate group than in the apixaban group (4.1 ± 2.1 vs. 2.9 ± 1.8 days). There were no significant differences observed between the two anticoagulant groups when comparing pre- and post-operative Hb values, post-operative blood loss and the other clinical parameters. CONCLUSIONS: Thus, it appears that the direct thrombin inhibitor, dabigatran etexilate, is associated with a longer period of wound secretion following the implantation of hip and knee endoprostheses than that associated with the Factor Xa inhibitor, apixaban.

The Transfemoral Approach for Removal of Well-Fixed Femoral Stems in 2-Stage Septic Hip Revision.

BACKGROUND: The value of a transfemoral approach for removal of well-fixed infected hip arthroplasties in 2-stage revision is unclear, especially whether cerclages for closure of the flap in the first step lead to higher reinfection rates and whether reopening of the flap for reimplantation of a hip arthroplasty leads to a lower union rate of the bony flap. METHODS: Seventy-six septic 2-stage revisions via a transfemoral approach with cerclages for closure of the flap in the first step and reopening of the flap for reimplantation were followed prospectively for a mean period of 51.2 ± 23.2 (24-118) months. RESULTS: The union rate of the bony flap after reimplantation was 98.7%, and no recurrence of reinfection was recorded in 93.4% of all cases. Subsidence of the stem occurred at a rate of 6.6%, dislocation at a rate of 6.6%, and there was no aseptic loosening of the implants. The Harris Hip Score was 62.2 ± 12.6 points with the spacer and 86.6 ± 15.5 points 2 years after reimplantation. Nine fractures (11.8%) of the flap occurred during the operation because of osteolytic or osteoporotic weakness of the flap itself, but these all healed without further intervention. CONCLUSION: The transfemoral approach is a safe method for septic revision of well-fixed hip prostheses, and the use of cerclage wires for closing the osteotomy flap in the first stage does not appear to lead to a higher reinfection rate. Similarly, the reopening of the flap does not appear to decrease the union rate of the flap.

How Useful Is Preoperative Aspiration before Revision of Unicompartmental Knee Prostheses Because of Osteoarthritis in the Other Compartments?

AIM: Periprosthetic joint infections (PJIs) of unicompartmental knee arthroplasties (UKAs) can lead to secondary osteoarthritis of the other compartments. The objective of this study was to identify the frequency of PJIs in cases of UKA with progressed secondary osteoarthritis and the result of septic one-stage revision in these cases to verify the value of preoperative aspiration in cases of secondary osteoarthritis of UKA. METHODS: We retrospectively reviewed 97 patients with a unicompartmental arthroplasty who underwent revision surgery to a total knee arthroplasty (TKA) between January 2013 and March 2021 because of subsequent osteoarthritis. Preoperative aspiration and sample collection during the revision surgery were employed to identify potential periprosthetic joint infections (PJIs). The post-revision period was monitored for septic complications over an average duration of 55.7 ± 25.2 months (24-113). RESULTS: PJIs were identified in 5.2% of cases through preoperative aspiration. In all instances of PJIs, a one-stage septic revision was performed, and notably, none of these cases experienced septic complications during the follow-up period. CONCLUSIONS: Preoperative aspiration is essential in order to exclude the presence of a PJI before performing revision surgery of UKA due to secondary osteoarthritis.

Revision total hip arthroplasty using a modular fluted, tapered revision femoral component and interlocking screws in Vancouver B3 periprosthetic fractures with insufficient bone at the isthmus.

Aims: Revision total hip arthroplasty in patients with Vancouver type B3 fractures with Paprosky type IIIA, IIIB, and IV femoral defects are difficult to treat. One option for Paprovsky type IIIB and IV defects involves modular cementless, tapered, revision femoral components in conjunction with distal interlocking screws. The aim of this study was to analyze the rate of reoperations and complications and union of the fracture, subsidence of the stem, mortality, and the clinical outcomes in these patients. Methods: A total of 46 femoral components in patients with Vancouver B3 fractures (23 with Paprosky type IIIA, 19 with type IIIB, and four with type IV defects) in 46 patients were revised with a transfemoral approach using a modular, tapered, cementless revision Revitan curved femoral component with distal cone-in-cone fixation and prospectively followed for a mean of 48.8 months (SD 23.9; 24 to 112). The mean age of the patients was 80.4 years (66 to 100). Additional distal interlocking was also used in 23 fractures in which distal cone-in-cone fixation in the isthmus was < 3 cm. Results: One patient (2.2%) died during the first postoperative year. After six months, 43 patients (93.5%) had osseous, and three had fibrous consolidation of the fracture and the bony flap, 42 (91.3%) had bony ingrowth and four had stable fibrous fixation of the stem. No patient had radiolucency around the interlocking screws and no screw broke. One patient had non-progressive subsidence and two had a dislocation. The mean Harris Hip Score increased from of 57.8 points (SD 7.9) three months postoperatively to 76.1 points (SD 10.7) 24 months postoperatively. Conclusion: The 2° tapered, fluted revision femoral component with distal cone-in-cone-fixation, combined with additional distal interlocking in patients with bony deficiency at the isthmus, led to reproducibly good results in patients with a Vancouver B3 fracture and Paprosky type IIIA, IIIB, and IV defects with regard to union of the fracture, subsidence or loosening of the stem, and clinical outcomes.

Diagnostic and prognostic relevance of plain radiographs for periprosthetic joint infections of the hip: a literature review.

Conventional radiography is regularly used to evaluate complications after total hip arthroplasty. In various recent consensus meetings, however, plain radiographs of a potentially infected hip joint have been judged as being only relevant to exclude diagnoses other than infection. Solid data on radiographic presentations of periprosthetic joint infection (PJI) are scarce. As a result, the prognostic value of radiological features in low-grade PJI remains uncertain. The present review article aims to present an overview of the available literature and to develop ideas on future perspectives to define the diagnostic possibilities of radiography in PJIs of the hip. The primary outcome of interest of this systematic review was the radiologic presentation of periprosthetic joint infections of the hip. As secondary outcome of interest served the sensitivity and specificity of the radiologic presentation of periprosthetic joint infections. Of the included articles, 26 were reviews, essays, or case reports and only 18 were clinical studies. Typical radiologic abnormalities of PJI were a periosteal reaction, a wide band of radiolucency at the cement-bone or metal-bone interface, patchy osteolysis, implant loosening, bone resorption around the implant, and transcortical sinus tracts. The frequency of their occurrence is still inadequately defined. A deeper understanding of the underlying causes and the relation between microorganisms to radiologic abnormalities can probably help clinicians in the future to diagnose a PJI. This is why further research shall focus on the radiographic features of PJI.

Diagnostics in Late Periprosthetic Infections-Challenges and Solutions.

The rising number of arthroplasties is combined with a rising number of periprosthetic joint infections, which leads to life-concerning consequences for the patients, including extended antibiotic treatment, further surgery and increased mortality. The heterogeneity of the symptoms and inflammatory response of the patients due to, e.g., age and comorbidities and the absence of a single diagnostic test with 100% accuracy make it very challenging to choose the right parameters to confirm or deny a periprosthetic joint infection and to establish a standardized definition. In recent years, additional diagnostic possibilities have emerged primarily through the increasing availability of new diagnostic methods, such as genetic techniques. The aim of the review is to provide an overview of the current state of knowledge about the various tests, including the latest developments. The combination of different tests increases the accuracy of the diagnosis. Each physician or clinical department must select the tests from the available methods that can be best implemented for them in organizational and technical terms. Serological parameters and the cultivation of the samples from aspiration or biopsy should be combined with additional synovial tests to create an accurate figure for the failure of the prosthesis, while imaging procedures are used to obtain additional information for the planned therapeutic procedure.

Effect of Multiantibiotic-Loaded Bone Cement on the Treatment of Periprosthetic Joint Infections of Hip and Knee Arthroplasties-A Single-Center Retrospective Study.

BACKGROUND: Two-stage septic revision is the prevailing method for addressing late periprosthetic infections. Using at least dual-antibiotic-impregnated bone cement leads to synergistic effects with a more efficient elution of individual antibiotics. Recent data on the success rates of multiantibiotic cement spacers in two-stage revisions are rare. METHODS: We conducted a retrospective follow-up single-center study involving 250 patients with late periprosthetic hip infections and 95 patients with prosthetic knee infections who underwent septic two-stage prosthesis revision surgery between 2017 and 2021. In accordance with the antibiotic susceptibility profile of the microorganisms, a specific mixture of antibiotics within the cement spacer was used, complemented by systemic antibiotic treatment. All patients underwent preoperative assessments and subsequent evaluations at 3, 6, 9, 12, 18, and 24 months post operation and at the most recent follow-up. RESULTS: During the observation period, the survival rate after two-step septic revision was 90.7%. Although survival rates tended to be slightly lower for difficult-to-treat (DTT) microorganism, there was no difference between the pathogen groups (easy-to-treat (ETT) pathogens, methicillin-resistant staphylococci (MRS), and difficult-to-treat (DTT) pathogens). Furthermore, there were no differences between monomicrobial and polymicrobial infections. No difference in the survival rate was observed between patients with dual-antibiotic-loaded bone cement without an additional admixture (Copal® G+C and Copal® G+V) and patients with an additional admixture of antibiotics to proprietary cement. CONCLUSION: Employing multiple antibiotics within spacer cement, tailored to pathogen susceptibility, appears to provide reproducibly favorable success rates, even in instances of infections with DTT pathogens and polymicrobial infections.