This study aimed to evaluate the impact of intraoperative direct sonication on the yield of traditional culture and the time to positivity (TTP) of cultures obtained for periprosthetic joint infection (PJI), thereby assessing its potential to improve diagnostic efficiency and reduce contamination risk. A prospective cohort study was conducted at a tertiary care center, involving 190 patients undergoing revision surgery for PJI from August 2021 to January 2024. Patients were included based on the 2018 International Consensus Meeting definition of PJI. The study utilized a novel sonication protocol, which involved direct intraoperative sonication of the implant and tissue, followed by incubation in a BACT/ALERT 3D system. The primary outcomes measured were the number and percentage of positive culture samples, identified microorganisms, and the TTP of each culture. Statistical analysis was performed using R software, with various tests applied to assess the significance of findings.Aim
Method
In recent years, many studies demonstrated the efficacy of an early switch to oral antibiotics after surgical treatment in orthopaedic related infections. However, large analyses on periprosthetic joint infections (PJIs) are lacking. We conducted a retrospective observational multicenter study in patients diagnosed with an early postoperative PJI (i.e less than 3 months after the index arthroplasty) treated with debridement, antibiotics and implant retention (DAIR). Patients from Europe and the USA were included. These two cohorts served as a quasi-randomised trial since an early oral antibiotic switch is routine practice in Europe versus a long duration of intravenous (IV) antibiotic treatment in the USA. Failure was defined as the clinical need for: i) a second DAIR, ii) implant removal, iii) suppressive antibiotic treatment or iv) infection related death.Introduction
Material and Methods
Stiffness postTotal Knee Replacement (TKR) is a common, complex and multifactorial problem. Many reports claim that component mal-rotation plays an important role in this problem. Internal mal-rotation of the tibial component is underestimated among surgeons when compared to femoral internal mal-rotation. We believe the internal mal- rotation of thetibial component can negatively affect the full extension of Knee. We performed an in-vivo study of the impact of tibial internal mal-rotation on knee extension in 31 cases. During TKR, once all bony cuts were completed and flexion/extension gaps balanced, we assessed the degree of knee extension using the trial component in the setting of normaltibial rotation and with varying degrees of internal rotation (13–33°, mean 21.2±4.6°). Intra-operative lateral knee X-ray was done to measure the degree of flexion contracture in both groups. We also compared the degree of flexion contracture between CR and PS spacers.Introduction
Method
Most of the algorithm available today to balance varus knee is based on a surgeon's hands-on experience without full understanding of pathological anatomy of varus knee. The high-resolution MRI allows us to recognize the anatomical details of the posteromedial corner and the changes of the soft tissue associated with the osteoarthritis and varus deformity. We have in this study, reviewed 60 cases of severe varus knee scheduled for TKR and compared it to normal MRI and those MRI were evaluated and read by a musculoskeletal radiologist. We have documented clearly the changes that happens in soft tissue, leading to tight medial compartment. We will also show multiple short intra-operative video confirming that MRI findings. We have retrospectively reviewed the MRI on 60 patients with advanced osteoarthritis varus knee. We also reviewed 20 MRI for a normal knee matched for age. We evaluated the posteromedial complex and MCL in sagittal PD-weighted VISTA to check the alignment of the MCL and posteromedial complex and the associate MCL bowing and deformity that could happen in osteoarthritis knee. We have measured the thickness of the posteromedial complex and the posterior medial bowing of the superficial MCL and the involvement of the posterior oblique ligament in those patients. To measure the posterior bowing of the MCL, a line was drawn through the posterior aspect of both menisci and we measured the distance between the posterior edge of MCL to that line in actual image. To measure the thickness of the posteromedial complex, we measured it at two areas in the posterior medial corner posteriorly at the level of the medial meniscus. Measuring the medial bowing of the MCL was done by a line drawn through the medial edge of the femoral condyle and the tibial condyle at the level of the medial meniscus to the inner aspect of the MCL. The normal distance between the posterior aspects of the MCL to the posterior meniscus line was approximately measured 2 cm. in average.Introduction
Material & method
Cementless Total Knee Replacement (TKR) was introduced to improve the longevity of implant; but has yet to be widely adopted because of reports of higher earlier failures in some series. The cementless TKR design has evolved recently and we have been using cementless component – both femoral and tibial on our patients. The long follow-up for fully TKR has been scarce in the literature. The purpose of this study isto investigate the minimum of ten years clinical and radiographic result of cementless titanium component and cementless tantalum component in primary TKR. From 2008 to 2010 317 TKR underwent primary total knee with cementless femoral component titanium based (Zimmer Nexgen) and cementless tantalum component monoblock tibial component, The surgery was performed mainly on younger patients - average age was 48 yrs old ranging from 26 yrs old to 62 yrs old. All surgeries were performed by single surgeon. All patients were followed clinically and radiographically for a minimum of 8 yrs. Mean 7.8 years and range from 7 to 9 years. The underlying diagnosis for majority of the cases were degenerative arthritis in 97 of the cases and rheumatoid arthritis on the 3%.Introduction
Material & method
The effect of intra-articular tranexamic acid on blood loss in concurrent bilateral total knee arthroplasty was studied in 60 patients in double blind fashion; one knee receiving tranexamic acid, the other knee receiving physiological saline acting as control. A single surgeon performed all operations utilising the same surgical technique and prosthesis. Mean blood loss from intra-articular drains was not significantly different, being 141ml in the tranexamic acid group and 163ml in the control group. Circumferential leg measurements at levels above, through and below the knees were not significantly different between groups on day two post-operatively compared to pre-operatively. Intra-articular tranexamic acid instillation did not lead to a significant reduction in blood loss in these patients.
The objective of this study was to evaluate the short term clinical and radiological results of a new short stem hip implant. In 29 consecutive patients suffering from osteoarthritis with 33 affected hip joints, the clinical and radiological results of 33 cementless hip arthroplasties using a cementless implanted short stem prosthesis type Aida and a cementless cup type Ecofit were evaluated prospectively between October 2009 and June 2015 in two hospitals. The median age of patients at time of surgery was 55 years (range, 30–71 years), 23 male and 10 female patients were included in the study. The median clinical follow up was 24 months (range, 1.5–51 months), and the median radiological follow up was 12 months (range, 1–51 months). Two patients were lost to follow up and two patients had only one immediate postoperative x- ray. The Harris Hip Score improved from a median preoperative value of 53 to a median postoperative value of 93 at follow up. Radiological analysis showed that 19 stems (58%) showed stable bony ingrowth, five cases (15%) showed stable fibrous ingrowth. Four cases need further follow up for proper evaluation of stem fixation. The short term survival of this new short stem is very promising, and achieving the goals of standard hip arthroplasty.
Gross deformity such as severe flexion contraction or severe varus deformity in both knees is better corrected simultaneously to prevent recurrence of flexion contracture and also to have equal leg length which facilitate proper physiotherapy post operatively. However, there is great reluctance in many institute to perform Simultaneous Bilateral Total Knee Replacement (SBTKR) fearing higher complication rate. The purpose of this paper is to show that SBTKR is economical, safe and sometimes is necessary in gross deformity such as bilateral flexion contracture. In this paper we will review the most recent literature about SBTKR which support our argument. Also we will review our cases of over 7500 of SBTKR done at our institution. In this study we will focus on the process that we went through at our institution to upgrade our medical care to enable to do this SBTKR safely. We will share also our post-operative protocol and some hint on the administrative level in order to perform SBTKR. In the last 20 years we performed over 7500 SBTKR, 15,000 implants. We have established at our institution a pre-operative team where this team included internist, physiotherapist, anesthesiologist and other medical sub specialty as recommended by the internist. The patient was pre-oped carefully and the extent of medical examination was determined by the internist and the anesthesiologist. Each patient care was determined preoperatively and also we have utilized special complexity scale that we have developed at our institution to reflect the complexity of the primary total knee replacement 1–5. The ASA and complexity scale is now routinely printed on our OR schedule. If the patient was cleared, SBTKR were carried on. The surgery is done first for the right side and after cementing the assistant will start the left side while the senior surgeon will clean the knee and then assist in the second knee. We have tried different modalities and the safest, less confusing was to first finish the first knee and after cementing the other limb was started by the assistant. The surgeon had only two assistants and one scrub nurse. Increasing the no. of assistant will make things more confusing. So we strongly recommend having only one senior surgeon. Post-operative care was almost identical to that of a single total knee replacement. We documented the complication rate, blood transfusion and unexpected ICU admission etc. in the SBTKR and we compared it to over 1000 cases of single knee replacement done at our institution by the same surgeon. The knee score was also was documented on both sides.INTRODUCTION
METHODS
The objective of this study was to evaluate the intermediate term clinical and radiological results of a new short stem hip implant. In 20 consecutive patients suffering from osteoarthritis with 25 affected hip joints (five cases were bilateral), the clinical and radiological results of 25 hip arthroplasties performed in one hospital between October 2009 and May 2014 through a minimally invasive anterolateral approach using a cementless short stem prosthesis type Aida and a cementless cup type Ecofit with a ceramic on ceramic pairing were evaluated prospectively. The median age of patients at time of surgery was 60 years (range, 42–71 years), 15 male (4 were bilateral) and 5 female patients (one was bilateral) were included in the study. The median clinical follow up was 30 months (range, 2–88 months), and the median radiological follow up was 30 months (range, 2–88 months).Aim
Methods
Early complication post total knee replacement reported to be higher in obese patient in general. Also the outcome of cruciate retaining and PS knee has been fully discussed before and there was no major difference in the outcomes for all the patients overall regardless of their weight. However, the purpose of this paper is to find out if the CR knee has superiority over PS knee in terms of clinical and functional outcomes and if early complication postTKR such as fracture and instability is more common in PS implant than in CR knee. This is a retrospective study comparing two groups of obese patients. The first using PS implant and the other using CR implant. These two groups were matched for age, body mass and severity of deformity. At our institution we have been using Persona implant which has the option of using PS insert or a CR. The decision to proceed with CR or PS mainly depends on the availability of the implant and also the ability to well balance the knee in patients. In most patients we try to proceed with CR implant. However, the flow of implant sometime sometimes limit us from using CR or the imbalance in the ligament force us to process with PS implant. We have reviewed a chart of over 200 patients in each group of obese patient they were done within the last three years. All cases had a minimum follow up of 6 months. Those groups were matched for body mass, age and severity of deformity. After matching the groups we documented Knee Society Score (KSS), Knee Society Function Score (KSFS), blood loss, post – operative pain and complications. All surgeries were performed by the same surgeon.Introduction
Materials & Methods
John Insall described medial release to balance the varus knee; the release he described included releasing the superficial MCL in severe varus cases. However, this release can create instability in the knee. Furthermore, this conventional wisdom does not correct the actual pathology which normally exists at the joint line, and instead it focuses on the distal end of the ligament where there is no pathology. We have established a new protocol consisting of 5 steps to balance the varus knee without releasing the superficial MCL and we tried this algorithm on a series of 115 patients with varus deformity and compared it to the outcome with a similar group that we have performed earlier using the traditional Insall technique. 115 TKR were performed by the same surgeon using Zimmer Persona implant in varus arthritic knees. The deformities ranged from 15 to 35 degrees. First, the bony resection was made using Persona instrumentation as recommended by the manufacturer. The sequential balancing was divided into 5 steps (we will show a short video demonstrating the surgical techniques for each step) as follows:
Step 1: Releasing of deep MCL Step 2: Excising of osteophyte Step 3: Excising of scarred tissue in the posteromedial corner soft phytes Step 4: Excision of the posteromedial capsule in case of flexion contracture Step 5: Releasing the semi-membranous (in gross deformity) We used soft tissue tensioner to balance the medial and lateral gaps. When the gaps are balanced at early step, there was no need to carry on the other steps. We used only primary implant and we did not have to use any constrained implant. We have compared this group with a similar group matched for deformity from previous 2 years where the conventional medial release as described by Insall.Introduction
Material and method
Tibial component malrotation is one of the commonest causes of pain and stiffness following total knee arthroplasties, however, the assessment of tibial component malrotation on imaging is not a clear-cut. The objective of this study was to assess tibial component rotation in cases with pain following total knee replacement using MRI with metal artifact reduction technique.Introduction
Aim
Stiffness post Total Knee Replacement (TKR) is a common, complex and multifactorial problem. Many reports claim that component mal-rotation plays an important role in this problem. Internal mal-rotation of the tibial component is underestimated among surgeons when compared to femoral internal mal-rotation. We believe the internal mal-rotation of the tibial component can negatively affect the full extension of Knee. We performed an in-vivo study of the impact of tibial internal mal-rotation on knee extension in 31 cases. During TKR, once all bony cuts were completed and flexion/extension gaps balanced, we assessed the degree of knee extension using the trial component in the setting of normal tibial rotation and with varying degrees of internal rotation (13–33°, mean 21.2±4.6°). Intra-operative lateral knee X-ray was done to measure the degree of flexion contracture in both groups. We also compared the degree of flexion contracture between CR and PS spacers.Introduction
Method
PSI technology have proved helpful in difficult primary Total Knee Replacement. However applying it to revision was impossible due to multiple factor. To Start with the landmark We usually destroy it. There is an extensive damage at the bone at the epiphysis, the implant prevent an accurate visualization and debridement usually change the surface of the bone as well which make applying the psi dyed impossible, we are proposing a new way of using psi in revision where we don't depend on the all masses adjusted in primary. However we depend on the metaphysical area of the bone. We have reviewed 56 MRI & CT scans for cases posted for revision and showed clearly that in spite of the extensive bony destruction and metal presence the MRI / CT scan we were able to visualize well the metaphysical area in the intramedullary canal in both tibial and femoral we have established a special external guide that depends on the outside surface of the metaphysis of the femur. We have tried this model on six plastic bone and showed that this external guide can give the accurate details that the surgeon is looking for in a revision surgeryIntroduction
Material & method
The convincible wisdom is that the release of MCL in severe varus knee should be progressive. This release is usually carried on after resecting the osteophyte and gradually carried on until the MCL is well balanced. However, sometimes, extensive release and releasing the superficial MCL can lead to instability in flexion. On a personal communication with many Asian surgeons they have been doing a careful release of the posteromedial corner in the varus knee and in majority of cases such release is adequate. And even in severe cases of varus knee superficial MCL doesn't need to be released. 20 total knee replacements were performed by the same surgeon using ZimmerPS implant. In the varus deformity ranges from 15–35 degrees. The first bony section was made carefully. All osteophytes were removed and resected. The posterior bone osteophytes were also resected and the intercondylar notches were made along with the posterior release. After doing the bony cut in 18 of those cases the medial compartment was still tight and both flexion and extension A careful release was carried in the postal medial corner-First using an osteotome around the posteromedial corner to release the soft tissue. After that the thick fibrous tissue that formed like pseudo meniscus was also resected until we were able to reach the posterior capsule. In some cases those scar tissues even extended to the capsule requiring the resecting of the postal medial capsule. We meticulously resected all those scar tissues and in many of those cases were able to visualize the MCL ligament which was well preserved. A tensioning device was used before and after the release. In all of those cases we were able to document an opening ranging from two to seven millimeter after the proper release. In all cases the superficial MCL were still intact and can be operated carefully This study clearly shows that we did not have to release the superficial MCL and the careful posteromedial release was adequate to obtain a good balance gap immediately and the knee was quite stable. The superficial MCL was maintained and preserved and tensioning device clearly document opening after releasing the postural medial cornerIntroduction
Result
3 main challenges encountered in knee revision of Asians: systemic: such as osteoporosis and laxity anatomical variance: established in literature making revision system not appropriate Neglected case revised late owes to extensive bone loss demanding bone substitute and increased constrain Therefore we like to alert surgeon apprehending enhanced challenges while indulging in revision of Asian. Our emiratus author with USA background/qualification/experience has excuted 216 revision in 8yrs with at least 3yrs follow-up. Between 2003–2010 we performed 216 revision TKR, reviewed all parameters & compared our results with European revision statistics depicting a) intermedullary canal smaller b) metaphysis narrower & more triangular in comparision to Caucasian causing housing mechanism fit impossible, also increase impingment of stem at times. Bone loss is normally quiet extensive & available implant including the Tantalum cone sometimes is difficult to fit in a tight metaphyseal area, we had satisfactory outcome inspite of owing to intra-operative complication which lead to 3 intramedullary fracture resulting from inadequate avalibity of smaller size, incomplete seating of tibial component, overhang of femoral component.it also leads to more translucent line quoted in 15 cases. Centre of IM canal in both tibia & femur is positioned more posteriorly especially in smaller size proven by CT anatomical study analysis. These data we related to anatomic variance rather then surgical technique therefore representing deficit of proper size thereby contributing to inability to surgeon.Introduction
Material & Method
Early complication post total knee replacement reported to be higher in obese patient in general. Also the outcome of cruciate retaining and PS knee has been fully discussed before and there was no major difference in the outcome. However, the purpose of this paper is to find out if early complication postTKR such as fracture and instability is more common in PS implant than in CR knee. This is a retrospective study comparing two groups of obese patients. The first using PS implant and the other using CR implant. These two groups were matched for age, body mass and severity of deformity. We clearly showed that there is significant increase in peri-prosthetic fracture and instability in the group that use PS implant. At our institution we have been using Persona implant which has the option of using PS insert or a CR. The decision to proceed with CR or PS mainly depends on the availability of the implant and also the ability to well balance the knee in patients. In most patients we try to proceed with CR implant. However, the flow of implant sometime sometimes limit us from using CR or the imbalance in the ligament force us to process with PS implant. We have reviewed a chart of over 200 patients in each group of obese patient they were done within the last three years. All cases had a minimum follow up of 6 months. Those groups were matched for body mass, age and severity of deformity. After matching the groups we documented knee score, blood loss, post – operative pain and complications. All surgeries were performed by the same surgeon.Introduction
Materials & Methods
In living normal knee the lateral femoral condyle rolls posteriorly more than the medial side to the extent that in deep flexion the lateral femoral condyle sublux from the tibial surface (Nakagawa et al). The purpose of this presentation is to study the tibiofemoral movement in patients who had full flexion after total knee replacements and to compare it with that of normal knee. 23 knees were scanned using SIEMENS SIREMOBILE Iso-C with 3D Extension C-arm. The system is able reconstruct 3D images that can be viewed from deferent angle and precise measurements of distances between the deferent components of the implant can be made. The knee was scanned while the patient is sitting in kneeling position with the calf touching the thigh (flexion of over 150 degree).INTRODUCTION
MATERIALS AND METHODS
PSI technology have proved helpful in difficult primary Total Knee Replacement. However applying it to revision was impossible due to multiple factor. To Start with the landmark We usually destroy it. There is an extensive damage at the bone at the epiphysis, the implant prevent an accurate visualization and debridement usually change the surface of the bone as well which make applying the psi dyed impossible, we are proposing a new way of using psi in revision where we don't depend on the all masses adjusted in primary. However we depend on the metaphysical area of the bone. We have reviewed 56 MRI &CT scans for cases posted for revision and showed clearly that in spite of the extensive bony destruction and metal presence the MRI / CT scan we were able to visualize well the metaphysical area in the intramedullary canal in both tibial and femoral · we have established a special external guide that depends on the outside surface of the metaphysis of the femur. We have tried this model on six plastic bone and showed that this external guide can give the accurate details that the surgeon is looking for in a revision surgeryIntroduction
Material & method
Balancing accurate rotational alignment, minimal overhang, and good coverage during total knee arthroplasty (TKA) often leads to compromises in tibial component fit, especially in smaller-sized Asian knees. This study compared the fit and surgical compromise between contemporary anatomic and non-anatomic tibial designs in Japanese patients. Size and shape of six contemporary tibial component designs (A:anatomic, B:asymmetric, C-F:symmetric) were compared against morphological characteristics measured from 120 Japanese tibiae resected following TKA surgical technique. The designs were then digitally placed on the resected tibiae. Each placement selected the largest possible component size, while ensuring <1mm overhang and proper alignment (within 5° of neutral rotational axis). When a compromise on either alignment or overhang was required (due to smaller-sized component unavailable), the design was flagged as “no suitable component fit” for that bone. Tibial coverage was compared across designs. Next, 32 femora were randomly selected from the dataset onto which each design was evaluated in two placements, the first maximizing coverage without attention to rotation and the second enforcing rotational accuracy. Downsizing was identified if in the second placement, enforcing rotational accuracy, required a smaller component size compared the first placement. The degree of mal-alignment while maximizing coverage, the incidence of downsizing, and difference in coverage between the two placements were compared across designs. Statistical significance was defined at p<0.05.INTRODUCTION
METHODS
