Adherence to a reliable PJI diagnostic protocol minimizes unsuspected positive cultures rate

The aim of the present study was to evaluate the incidence of unsuspected PJI when prosthetic revisions are thoroughly evaluated by PJI dedicated orthopedic surgeon before surgery. The hypothesis is that the incidence of unsuspected PJI is reduced by applying this protocol. This is a historical cohort study carried out in one university hospital. The prosthetic revision assessment was carried out in January 2019. From that date on, all patients that were programmed for hip or knee revision (either by an orthopedic surgeon specialized or not in septic revisions) were scheduled for a preoperative visit with the same orthopedic surgeon specialized in septic revisions. The diagnostic algorithm applied was based on the Pro-Implant Foundation diagnostic criteria. Prior to the revision assessment, the indication for joint aspiration was done at the surgeons' discretion (non-specialized in septic revisions) and the preoperative identification of PJI was also done by a hip or knee surgeon (not specialized in septic surgery). Based on the PIF criteria, there were 15 infections among the revisions in group 1 and 18 PJI in group 2 (p > 0.05). The most interesting finding was that there were 7 patients with unsuspected positive cultures in group 1. That represents 11% of all revisions. No patient in group 2 was found with unsuspected positive cultures (p < 0.001). A thorough PJI diagnostic algorithm should be implemented before prosthetic revision to avoid unsuspected positive cultures

Bone Cut Accuracy in Total Knee Arthroplasty: Do Conventional Cutting Guides Stay True to the Planned Coronal Orientation of the Components?

Background: Total knee arthroplasty (TKA) has become the gold standard for the definitive treatment of knee osteoarthritis. One crucial aspect in the implantation of a TKA is the precise orientation of the femoral and tibial components. The main purpose of the present study is to assess, in patients undergoing total knee replacement, whether the difference between the planned angulation in the distal femoral cut and the angulation obtained in the postoperative radiological control is low enough to consider the conventional bone-cutting guides reliable. Methods: A retrospective study was designed with a consecutive series of patients who had undergone primary total knee arthroplasty using conventional instrumentation over one year. The authors analysed the main variable (bone cuts) while considering different variables (age, gender, surgeon, prosthesis, laterality, constraint, body mass index and alignment) to identify different patient patterns that justify the results in the main variable. Descriptive variables were analysed using the Mann–Whitney U and Kruskal–Wallis tests. Additionally, the correlation between continuous variables was explored in accordance with the Spearman correlation. Results: A total of 340 patients with a mean age of 75 ± 9.16 years were finally included in the present study. The mean absolute error of the main variable for the femoral coronal bone cut was 1.89° (SD 1.53). For the tibial coronal bone cut, it was 1.31° (SD 2.54). These values correspond to what remains after subtracting the radiological angulation obtained in the postoperative period from the planned intraoperative angulation of the distal femoral cut. No associations were observed between the main variable (the angulation of the proximal tibial cut and distal femoral cut) and the rest of variables for either the femur or tibia. Conclusion: A discrepancy between the planned angulation and the final radiological measure on the coronal plane of the femur and tibia using conventional cutting guides has been demonstrated. The degree of deviation is low enough that it probably does not affect clinical outcomes. Therefore, the use of conventional cutting guides will continue to be an appropriate tool to perform bone cuts in knee replacement surgery

Transcultural adaptation and validation of the ' Hip and Knee ' questionnaire into Spanish

BACKGROUND: The purpose of the present study is to translate and validate the 'Hip and Knee Outcomes Questionnaire', developed in English, into Spanish. The 'Hip and Knee Outcomes Questionnaire is a questionnaire planned to evaluate the impact in quality of life of any problem related to the human musculoskeletal system. 10 scientific associations developed it. METHODS: The questionnaire underwent a validated translation/retro-translation process. Patients undergoing primary knee arthroplasty, before and six months postoperative, tested the final version in Spanish. Psychometric properties of feasibility, reliability, validity and sensitivity to change were assessed. Convergent validity with SF-36 and WOMAC questionnaires was evaluated. RESULTS: 316 patients were included. Feasibility: a high number of missing items in questions 3, 4 and 5 were observed. The number of patients with a missing item was 171 (51.35%) in the preoperative visit and 139 (44.0%) at the postoperative. Internal validity: revision of coefficients in the item-rest correlation recommended removing question 6 during the preoperative visit (coefficient <0.20). Convergent validity: coefficients of correlation with WOMAC and SF-36 scales confirm the questionnaire's validity. Sensitivity to change: statistically significant differences were found between the mean scores of the first visit compared to the postoperative. CONCLUSION: The proposed translation to Spanish of the 'Hip and Knee Questionnaire' is found to be reliable, valid and sensible to changes produced at the clinical practice of patients undergoing primary knee arthroplasty. However, some changes at the completion instructions are recommended. LEVEL OF EVIDENCE: Level I. Prognostic study

Thermodynamic approach of meat freezing process

[EN] Frozen storage is a method widely implemented in meat industry in order to maintain the nutritional value and sensorial characteristics of meat products. The aim of this research was to implement and validate the use of the infrared technique as a non-destructive control tool to monitor the physicochemical phenomena that occurred during the freezing stage. This enables to evaluate the final impact of this operation in a complex system such as meat To do this, the evolution of the freezing process in pork loin (Longissimus dorsi) was followed by a thermographic camera Optris PI (R) 160 thermal imager (Optris GmbH, Berlin, Germany), whose spectral infrared range of wavelength is comprised between 7.5 and 13 mu m. The results obtained have demonstrated the existence of a chemical potential gradient which caused an internal flux of water. In turn, as a result of nucleation phenomena and the influence of the surface tension existent, a new water chemical potential gradient appeared, leading to the displacement of water molecules towards the ice agglomerates. This provoked the progressive dehydration of the tissue areas immediately close to the ice crystals. Micrographs obtained in different positions of the meat tissue confirm this theory. Industrial relevance: Currently, there is a significant gap in the knowledge of the complex phenomena that occurred during food freezing. This research develops a thermodynamic model which provides an accurate explanation and a new insight of the main mechanisms involved in the meat freezing process. Moreover, this model enables to leave a proof of the real structural impact that occurred in the muscular tissues, as a consequence of the generation of ice crystals and agglomerates. In order to carry out this research, the thermal imaging (TI) technique has been used. This is an innovative and emergent technology whose popularity and use at the food industry has experienced a significant growth in recent years. The results obtained represent a starting point for the future development of on-line cold chain monitoring systems in the food industry. The aim is no other than to provide the necessary basis to meet current demands for food quality and safety. (C) 2014 Elsevier Ltd. All rights reserved.The authors acknowledge the financial support from the Spanish Ministerio de Ciencia e Innovacion throughout the project AGL2011-30096.Castro Giráldez, M.; Balaguer-Cuenca, N.; Hinarejos, E.; Fito Suñer, PJ. (2014). Thermodynamic approach of meat freezing process. Innovative Food Science and Emerging Technologies. 23:138-145. https://doi.org/10.1016/j.ifset.2014.03.007S1381452

Incidence, functional outcomes and cure rate of hematogenous infection in a 2,498 Total Knee Arthroplasties cohort

Abstract Purpose The primary aim of the present study is to report the late acute hematogenous (LAH) prosthetic joint infection (PJI) cure rate following Total knee arthroplasty (TKA) treated by means of debridement, antibiotics, and implant retention (DAIR) in a long‐term follow‐up. The secondary purpose is to report the functional outcomes at that follow‐up and to compare them with a non‐infected group. Material and Methods This study cohort consists of 2,498 TKA performed from September 2005 to April 2010 that had a minimum follow‐up of 10 years. The diagnosis of PJI and classification into LAH was done in accordance with the Zimmerli criteria. The primary outcome was the failure rate, defined as death before the end of antibiotic treatment, a further surgical intervention for treatment of infection, life‐long antibiotic suppressive treatment or chronic infection. The Knee Society Score (KSS) was used to evaluate clinical outcomes. Results Ten patients were diagnosed with acute hematogenous PJI during the study period (0.4%). All of them were managed with DAIR, which was performed by a knee surgeon and/or PJI surgeon. The failure rate was 0% at the 8.5‐year (SD, 2.4) follow‐up mark. The KSS score was 82.1 vs. 84.1 (p n.s.) at final follow‐up. Conclusion Although the literature suggests that TKA DAIR for LAH periprosthetic joint infection is associated with high rates of failure, the results presented here suggest a high cure rate with good functional outcomes. Level of evidence Level II, prospective cohort study

A new score assessing the surgical wound of a TKA and its relation with pain, infection and functional outcomes.

The aim of this study was to describe a new score to measure the aspect of the TKA surgical wound and to correlate it with postoperative pain, infection and functional outcomes at 1 year of follow-up. This score, ranging from 0 to 10, assessed 5 parameters; swelling, haematoma, erythema, blood draining and blisters. 159 consecutive TKA were prospectively evaluated.             Intra and inter-rate reliability was superior to 0.9. No differences were obtained comparing the aspect of the surgical wound with postoperative pain or functional outcomes. Incidence of deep infection is directly related with an increased score (p=0.0025).

Increased posterior translation but similar clinical outcomes using ultracongruent instead of posterior stabilized total knee arthroplasties in a prospective randomized trial

Data de publicació electrònica: 26-08-2021Purpose: The aim of this study was to compare the posterior tibial translation after ultracongruent (UC) and posterior-stabilized (PS) total knee arthroplasty (TKA) with two different UC with different heights in the anterior lip, and two different PS designs. This study also aimed to compare the range of motion (ROM) and outcomes scores after the use of these TKA models. It was hypothesised less posterior tibial translation after PS than after UC TKA, and less posterior tibial translation with a higher anterior lip in the UC insert than with a lower one. Methods: It was designed as a prospective randomized study of a group of 120 patients operated with a cemented TKA. To clarify the main purpose of the study, four groups were analysed using different polyethylene designs: Triathlon PS insert in group one, Triathlon UC insert in group two, U2 PS insert in group three and U2 UC insert in group four. One year after surgery, a forced posterior drawer with a Telos Stress applying 15 kg of force posteriorly on the proximal tibia at 90° of knee flexion was analysed in the lateral radiograph. Limb alignment, tibial posterior slope and posterior condylar offset were also studied. Results: 30 patients were included in each group. The average age was 73 years. There were 72.2% female and 27.8% male patients. There were no significant differences in any demographic or radiographic studied variables, preoperative range of motion (ROM) or preoperative Knee Society Scores (KSS) among the different groups. One year after surgery, the average postoperative ROM and the postoperative KSS Knee and KSS Function scores improved in respect of the preoperative values in all the groups. There were no significant differences in the postoperative outcome scores among the different groups (p = n.s.). Postoperative alignment of the limb, tibial posterior slope and posterior condylar offset were similar in the 4 study groups (p = n.s.). The postoperative posterior tibial translation was different between groups: the PS groups (groups 1 and 3) showed significant inferior values (p < 0.001) in respect of the UC groups (groups 2 and 4). There were no differences between both groups of PS models, but there was a significant increase in the posterior tibial translation of the Triathlon UC insert (11.2 mm SD 3.2) in respect of the U2 UC insert (6.1 mm SD 4.5) (p = 0.004). Conclusions: UC inserts restrict the posterior tibial translation after TKA less than PS inserts, but a design with a high anterior lip in the polyethylene UC insert can better control the posterior tibial translation than an insert with a small anterior lip

Barbed sutures in total knee arthroplasty: are they really useful? a randomized controlled trial

Data de publicació electrónica: 20-05-2019Bidirectional barbed sutures (BBSs) have recently been investigated in total knee arthroplasty (TKA). The contrasting results from the scarce literature suggest that BBSs are safe, save time and money, and give results comparable to traditional sutures. The purpose of the study is to test the real effect of BBSs on closure time in TKA and assess the functional results as well as the complications related to them. It was a randomized controlled trial. Eighty-five patients undergoing primary TKA were assigned to receive traditional closure with Vicryl (V-group) or with BBSs (Q-group). The exclusion criteria were significant coronal deformity, flexion contracture, or the need for stem and/or augmentation. The closure time for the capsule and that for the subcutaneous layer were registered separately. Intraoperative incidences were recorded. The follow-up was up to 1 month, during which the range of motion (ROM), superficial or deep infection, and wound dehiscence were assessed. There was a significant reduction in the capsule layer (27 seconds; p = 0.02) and global time closure (51 seconds; p = 0.01) in the Q-group. No differences were found in the subcutaneous layer (24 seconds; p = 0.055). There were more intraoperative suture breakages in the Q-group, mainly in the subcutaneous layer (p < 0.001). No differences in terms of dehiscence, infection, and ROM were observed at the 1-month follow-up. BBSs allow for slightly faster wound closure than Vicryl during a TKA. However, the differences observed have minimal clinical repercussions. Moreover, no differences in the infection rate (deep or superficial), dehiscence, or ROM were found

Pressure algometry is a useful tool to quantify pain in the medial part of the knee: An intra- and inter-reliability study in healthy subjects.

PURPOSE: Pain quantification is essential for diagnostic and pain monitoring purposes in disorders around the knee. Pressure algometry is a method described to determine pressure pain threshold (PPT) by applying controlled pressure to a given body point. The purpose of this study was to determine the reliability of this method when it was applied to the medial part of the proximal tibia metaphysis and to evaluate the PPT levels between genders. METHODS: Fifty healthy (mean age; 46.9) volunteers were recruited, 25 men and 25 women. Pressure algometry was applied to a 1 cm(2)-probe area on the medial part of the knee by 2 raters. Intra- and interclass correlation (ICC) was obtained and differences between genders were evaluated. Bland-Altman plots were performed to evaluate the variability of the measures. RESULTS: The mean values of PPT obtained by rater 1 and 2 were 497.5 Kpa and 489 Kpa respectively. The intrarater reliability values (95% IC) for rater 1 and 2 were 0.97 (0.95-0.98) and 0.84 (0.73-0.90) respectively. With regard to interrater reliability, the ICC (95% IC) for the first measurement was 0.92 (0.87-0.95) and 0.86 (0.78-0.92) for the second one. Women showed significant lower values of PPT than men. The Bland-Altmand plots showed excellent agreement. CONCLUSIONS: Pressure algometry has excellent reliability when it is applied to the medial part of the proximal metaphysis of the tibia. Women have lower values of PTT than men. The high reliability of the PA in an individual volunteer makes it a more valuable tool for longitudinal assessment of a given patient than for comparison between them. LEVEL OF EVIDENCE:/nLevel III. Prospective study

Proximal tibiofibular dislocation in closing-wedge high tibial osteotomy increases the risk of medium and long-term total knee replacement

Proximal tibiofibular dislocation in closing-wedge high tibial osteotomy increases the risk of medium and long-term total knee replacement. Background: High tibial osteotomy is an effective treatment for medial osteoarthritis in young patients with varus knee. The lateral closing-wedge high tibial osteotomy (CWHTO) may be managed with tibiofibular dislocation (TFJD) or a fibular head osteotomy (FHO). TFJD may lead to lateral knee instability and thereby affect mid- and long-term outcomes. It also brings the osteotomy survival rate down. Objective: To compare the CWHTO survival rate in function of tibiofibular joint management with TFJD or FHO, and to determine whether medium and long-term clinical outcomes are different between the two procedures. Material & Methods: A retrospective cohort study was carried out that included CWHTO performed between January 2005 to December 2018. Those patients were placed in either group 1 (FHO) or Group 2 (TFJD). Full-leg weight-bearing radiographs were studied preoperatively, one year after surgery and at final follow-up to assess the femorotibial angle (FTA). The Rosenberg view was used to assess the Ahlbäck grade. The Knee Society Score (KSS) was used to assess clinical outcomes and a Likert scale for patient satisfaction. The total knee replacement (TKR) was considered the end of the follow-up and the point was to analyze the CWHTO survival rate. A sub-analysis of both cohorts was performed in patients who had not been FTA overcorrected after surgery (postoperative FTA ≤ 180°, continuous loading in varus). Results: A total of 230 knees were analyzed. The follow-up period ranged from 24-180 months. Group 1 (FHO) consisted of 105 knees and group 2 (TFJD) had 125. No preoperative differences were observed in terms of age, gender, the KSS, FTA or the Ahlbäck scale; neither were there any differences relative to postop complications. The final follow-up FTA was 178.7° (SD 4.9) in group 1 and 179.5° (SD 4.2) in group 2 (p = 0.11). The Ahlbäck was 2.21 (SD 0.5) in group 1 and 2.55 (SD 0.5) in group 2 (p = 0.02) at the final follow-up. The final KSS knee values were similar for group 1 (86.5 ± 15.9) and group 2 (84.3 ± 15.8). Although a non-significant trend of decreased HTO survival in the TFJD group was found (p = 0.06) in the sub-analysis of non-overcorrected knees, which consisted of 52 patients from group 1 (FHO) and 58 from group 2 (TFJD), 12.8% of the patients required TKR with a mean of 88.8 months in group 1 compared to 26.8% with a mean of 54.9 months in the case of group 2 (p = 0.005). However, there were no differences in clinical and radiological outcomes. Conclusion: TFJD associated with CWHTO shows an increase in the conversion to TKR at medium and long-term follow-up with lower osteotomy survival than the CWHTO associated with FHO, especially in patients with a postoperative FTA ≤ 180° (non-overcorrected). There were no differences in clinical, radiological or satisfaction results in patients who did not require TKR. Level of evidence III. Retrospective cohort study