Aims

The aim of this study was to surveil whether the standard operating procedure created for the NHS Golden Jubilee sufficiently managed COVID-19 risk to allow safe resumption of elective orthopaedic surgery.

In January 2012, the Department of Health reportedly claimed that data demonstrated ‘half of knee surgery does not substantially change the outcome for patients: their mobility is not improved that much, nor their pain’. Furthermore, in recent years knee replacement surgery has been described as a procedure of limited clinical value (PLCV) by commissioning bodies nationwide. This study aimed to establish whether patients in Reading were satisfied with their surgery at five years and whether there was an objective improvement in their pain and function following surgery.

Five-year data was retrospectively reviewed from 130 knee replacements performed between January 2004 and July 2005. Patient details, intra-operative data and patient reported outcome measures (PROMs) were downloaded from our OrthoWave database. The Oxford Knee Score was completed pre-operatively, at six months and then yearly to five years, measuring pain and function specific to the knee operated on. In addition, patients were asked directly whether they felt satisfied with their joint replacement surgery.

The sample population consisted of 52 males and 78 females, with a mean age of 70 and mean body mass index of 30.2. Twenty-three of the patients had undergone uni-compartmental surgery (either Oxford or St George), with the remainder having either PFC or Scorpio total knee replacements. The mean pre-operative Oxford Knee Score was 20.4. The mean improvement in scores at six months was 14.77 (95% confidence interval 13.25–16.28, p<0.0001) and 17.23 at five years (95% confidence interval 15.66–18.79, p<0.0001). On direct questioning, 85.6% of patients were satisfied with their knee replacement, 3.4% were dissatisfied and 10.9% remained unsure. Reasons identified for dissatisfaction included chronic pain syndromes and the need for early revision surgery.

Patient reported outcome measures are increasingly being used to justify outcomes of surgery and the Oxford Knee Score is particularly helpful as it relates function and pain to the knee operated on, whilst attempting to minimise the effect of confounding co-pathology. This five-year data suggests that the majority of patients are satisfied with their knee surgery. A significant improvement in pain and function is evident at six months post-operatively and continues to be demonstrable at five years, supporting the British Orthopaedic Association's strong rebuttal of the recent negative press regarding knee surgery.

Introduction. A proportion of patients with hip and knee prosthetic joint infection (PJI) undergo multiple revisions with the aim of eradicating infection and improving quality of life. The aim of this study was to describe the microbiology cultured from multiply revised hip and knee replacement procedures to guide antimicrobial therapy at the time of surgery. Patients and Methods. Consecutive patients were retrospectively identified from databases at two specialist orthopaedic centres in the United Kingdom between 2011 and 2019. Patient were included who had undergone repeat revision total knee replacement (TKR) or total hip replacement (THR) for infection, following an initial failed revision for infection. Results. 106 patients were identified, of which 74 underwent revision TKR and 32 underwent revision THR. Mean age at first revision was 67 years (SD 10). Charlson Comorbidity Index was <2 for 31 patients, 3–4 for 57 patients, and >5 for 18 patients. All patients underwent >2 revisions, 73 patients received 3, 47 patients received 4, 31 patients received 5, and 21 patients received >6. After six revisions, 90% of patients cultured different organisms than the initial revision, and 53% of organisms were multi-drug resistant species. The most frequent organisms at each revision were coagulase negative Staphylococcus (36%) and Staphylococcus aureus (19%). Fungus was cultured from 3% of revisions and 21% of infections were polymicrobial. Conclusion. Patients undergoing multiple revisions for PJI are highly likely to experience a change in organisms and sensitivities with each subsequent revision. It is important to administer empirical antibiotics at each subsequent revision, appreciating known drug resistance from previous cultures. Our results do not support routine use of empirical antifungals

Aim. The prevalence of unexpected positive cultures (UPC) in aseptic revision surgery of the joint with a prior septic revision procedure in the same joint remain unknown. The purpose of this study was to determine the prevalence of UPC in aseptic revisions performed in patients with a previous septic revision in the same joint. As secondary outcome measure, we explore possible risk factors associated with UPC and the re-revision rates. Method. This retrospective single-center study includes all patients between January 2016 and October 2018 with an aseptic revision total hip or knee arthroplasty procedure with a prior septic revision in the same joint. Patients with less than three microbiology samples, without joint aspiration or with aseptic revision surgery performed <3 weeks after a septic revision were excluded. UPC was defined as a single positive culture in a revision that the surgeon had classified as aseptic according to the 2018 International Consensus Meeting. Results. A total of 139 revision total hip/knee arthroplasties in patients with a previous septic revision were performed during the study period. After excluding 47 cases with insufficient information, a total of 92 patients were recruited for final analysis. The patient cohort consist of 52 males and 40 females with a mean age of 70 years (±10.6). There were 66 (71.7%) hips and 26 (28.3%) knees. The mean time between the septic and the aseptic revision was 83 months (±89). The two main causes for the aseptic revision were aseptic loosening (n=57, 62%) followed by instability (n=21, 22.9%). We identified 11 (12%) UPC in the entire cohort, while in 3 cases there was a concordance of the germ compared to the previous septic surgery. There were no differences for the presence of UPC between hips and knees (p=0.282), diabetes (p=0.701), immunosuppression (p= 0.252), previous one-stage or two-stages septic revision (p=0.316), or between the causes for the aseptic revision ((p=0.429). There was no correlation between the UPC and time after the septic revision (p=0.773). Conclusions. The prevalence of UPC in this specific group was similar to those reported in the literature for aseptic revisons. More studies, regarding this patient group are necessitated to better understand and more securely interprete the results in those high-risk aseptic revisions

Aim. Synovial fluid investigation is the best alternative to diagnose prosthetic joint infection (PJI) before adequate microbiological/histology sampling during revision surgery. Although accurate preoperative diagnosis is certainly recommended, puncturing every patient before revision arthroplasty raises concerns about safety and feasibility issues especially in difficult to access joint (e.g., hip), that often require OR time and fluoroscopy/ultrasound guidance. Currently there is no clear guidelines regarding optimal indications to perform preoperative joint aspiration to diagnose PJI before revision surgery. The main goal of this study is to determine the accuracy of our institutional criteria using the new European Bone and Joint Infection Society (EBJIS) PJI definition. Method. We retrospectively evaluated every single- or first-stage for presumed aseptic or known infected revision total hip/knee arthroplasty procedures between 2013–2020. Preoperative clinical and laboratory features were systematically scrutinized. Cases with insufficient information for accurate final PJI diagnosis (i.e., no perioperative synovial fluid examination or no multiple cultures including sonication of removed implant) were excluded. Preoperative joint aspiration is recommended in our institution if any of the following criteria are met: 1) elevated CRP and/or ESR; 2) early failure (<2 years) or repeat failure; 3) high clinical suspicion/risk factors are present. Performance of such criteria were compared against final postoperative EBJIS definition PJI diagnosis. Results. A total of 364 revision THAs or TKAs were performed during the study period. After excluding 258 cases with insufficient information, a total of 106 patients were ultimately included. 38 (35,8 %) were classified as confirmed infections, 10 (9.4 %) as likely infected and 58 (54.7%) as infection unlikely. Of those, 37 confirmed infection cases, 9 likely infected cases and 32 infection unlikely cases did have indication for preoperative synovial fluid collection before revision surgery. Institutional criteria showed 95.8 % Sensitivity, 44.83 % Specificity, 92.9 % Negative Predictive Value (NPV) and 59 % Positive Predictive Value (PPV). Conclusions. Sensitivity and NPV of the aforementioned institutional criteria are very high even with the use of the more sensitive EBJIS PJI definition. As such they seem to be a valid alternative in selecting patients that should be punctured before revision arthroplasty. They identify the vast majority of infected patients while saving a significant number of patients from unnecessary procedures

Postoperative radiological assessment is used to evaluate the success of knee replacement procedures. Load-bearing long-standing anterior-posterior (AP) x-rays are typically used for this assessment. For knee replacement procedures the five landmarks that are identified are: 1) hip centre; 2) femoral knee centre; 3) tibial knee centre; 4) medial malleolus; and 5) lateral malleolus. These landmarks are used to identify the femoral and tibial reference mechanical axes. However, variations in the x-ray acquisition process and foot rotation can lead to errors in this assessment. In the past, researchers have studied the effect of foot rotation and flexion on estimation of knee alignment. In our study, the use of digitally reconstructed radiographs (DRRs) allows us to vary the x-ray acquisition parameters and observe the effect of these changes to estimations of the mechanical axes. We also measured the inter-user variability in these measurements. Our results show that AP x-rays can be used to accurately estimate the femoral and tibial mechanical axes

Aim. C-reactive protein(CRP) and erythrocyte sedimentation rate(ESR) are non-specific markers with variable reported accuracy in the diagnosis of prosthetic joint infection(PJI). They are often used as a part of the initial diagnostics as they are widely available and inexpensive. Given its high false-negative rate, CRP is an insufficient screening tool for PJI especially in low virulence microorganisms. Nevertheless, many advocate ESR offers no added advantage and is useless in this setting. Our goal is to determine if the combined measurement of ESR and CRP offers increased sensitivity for the preliminary screening of PJI over isolated CRP measurement. Method. We retrospectively evaluated every single- or first-stage for presumed aseptic or known infected revision total hip/knee arthroplasty procedures between 2013–2018. Cases without preoperative CRP and ESR measurement as well those without synovial fluid for differential leukocyte count and/or no multiple cultures including sonication of removed implant obtained during surgery were excluded. Diagnostic accuracy was compared against two different PJI definitions: 2013 International Consensus Meeting and ProImplant Foundation definitions. Results. A total of 398 revision were performed during the study period. After excluding 293 cases with insufficient information, a total of 105 patients were studied. Naturally, CRP and ESR mean values were significantly higher among PJI cases compared to aseptic cases. When compared against 2013 International Consensus Meeting definition, CPR has a sensibility 86.5% (45/52) that increases to 94.2% (49/52) with the combined measurement (ESR and CRP). The sensitivity also increased when compared against the ProImplant Foundation definition (72.6% (45/62) vs 85.5% (53/62)). Conclusions. After the inciting insult, CRP raises and drops rapidly and ESR response is slower but also much more enduring. One can only hypothesize that chronic PJI runs perhaps a fluctuating inflammatory course that can sometimes be more accurately picked up by ESR and not CRP measurement. Our results seem to corroborate that ESR measurement is a valid adjunct to isolated CRP measurement in the initial screening of PJI in painful total joint arthroplasties

Patellofemoral complaints are the common and nagging problem after total knee arthroplasty. Crepitus occurs in 5% to over 20% of knee arthroplasty procedures depending on the type of implant chosen. It is caused by periarticular scar formation with microscopic and gross findings indicating inflammatory fibrous hyperplasia. Crepitus if often asymptomatic and not painful, but in some cases can cause pain. Patella “Clunk Syndrome” is less common and represents when the peripatella scarring is abundant and forms a nodule which impinges and “catches” on the implant's intercondylar notch. Patella Clunk was more common with early PS designs due to short trochlear grooves with sharp transition into the intercondylar notch. Clunks are very infrequent with modern PS implants. This syndrome has been reported in CR implants as well. Thorough debridement of the synovium and scarring at the time of arthroplasty is thought to reduce the occurrence of crepitus and clunks. Larger patella with better coverage of the cut bone may also be helpful. The diagnosis can be made on history and physical exam. X-rays are also helpful to assess patella tracking. MRI or ultrasound can be used to identify and confirm the diagnosis, but this is not mandatory. Painful crepitus and clunk syndrome that fail conservative management of NSAIDS and physical therapy may require surgery. Both crepitus and clunk can be treated with arthroscopic removal of the peripatella scar. Patella maltracking should also be assessed and treated. While recurrence may occur, it is uncommon

Background. We identified several opportunities to significantly reduce cost for hip and knee arthroplasty procedures:. Customized instruments: by identifying the essential instruments for arthroplasty cases, we managed to have one universal tray for each case, and 3 specific trays from the implant manufacturing company. Customized wrap-free, color-coded, stackable trays: by using a wrap-free trays, preparation time in central sterile, opening tray time in OR and turn-over time were reduced. Also, stackable trays were organized based on side and size, therefore only 2 trays needed to be used in each case. Discounted implants: negotiated through optional case coverage with revision system and reps available as backup. Optional rep coverage protocols: designed through process management of the operating room surgical staff and central sterile. Aim of the study was to measure the cost savings, efficacy, and outcomes associated with primary total hip and knee arthroplasty by implementing these protocol. Methods. This is a prospective study from January to October 2016 for selected primary total hip and knee arthroplasties were performed with the above protocols by 2 experienced arthroplasty trained surgeons, were followed for minimum 3 months. Initiating the cost saving protocols were achieved by re-engineering customized trays, discounted implants through optional case coverage (Sourced Based Selection of a Cooperating Manufacturer, MTD), and focused on process management of the staff training. Staff responsibilities were divided into 2 categories:. Familiarity of the instruments, implant, and techniques; trays set up and assurance of availability of the implants. These responsibilities were covered by a trained OR technician and the surgeon. Final verification of the accurate implants prior to opening the packaging. This was achieved by a trained OR nurse and the surgeon. Results. We did not have any intra-operative complications. We also did not encounter any issued with the trays or errors in opening of the implants. There were no re-admissions, fracture, dislocation, or infection. The mean length of stay was 2.2 ± 0.5 days (range 1–3 days) with 68% home discharges. The cost of the implant was reduced from $4,800 to $1,895 with $2,905 cost saving per case and total savings of $58,100. The projected savings only for uncomplicated primary total hip arthroplasty (minimum 120 cases/year between 2 surgeons) is $384,600. Further cost saving from the process management changes were seen in central sterile processing time. Prior to the one tray system, the hospital had 3 in-house trays and there were 4 device company trays. We also noticed an approximate 27% improvement in turnover time. Conclusion. Repless model has significant cost saving potential. Preparation for the transition, proper patient selection, standardization of the trays and implants, and distribution of the responsibilities between OR nurses, technicians and the surgeon are essential

It has been shown that a cognitive function (CF) loss can occur after hip or knee arthroplasty procedures, with an incidence of 40 to 70%. The pathogenesis remains unclear but studies suggest some form of brain emboli; although both trans-cranial doppler and trans-oesophageal doppler have both shown emboli per-operatively a correlation has never been shown with CF loss post-operatively. In contrast, in the cardiothoracic literature an embolic cause is widely accepted for detectable post-operative CF drop. The purpose of this study was to ascertain whether MRI could show evidence of embolic phenomena in patients undergoing hip or knee arthroplasty. Twenty-five patients presenting for hip or knee arthroplasty procedures were consented for this study. Brain MRI scans and MR angiograms were performed 1 week pre-operatively and within 1 week post-operatively using a Phillips 1.5Tesla MRI unit. All scans recorded were independently reviewed by 2 radiologists. A series of tests to examine several modes of cognitive function were carried out by a clinical psychologist pre-operatively, and at 1 week post-operatively. The CF tests showed a clinically significant drop following surgery in 64% of cases – this is in keeping with other recently published data. None of the post-operative scans or angiograms showed overt evidence of new lesions. Three Scans had equivocal tiny brainstem hypodensities on a single slice with no correlating abnormality on diffusion images to support the presence of new ischaemia. We conclude that either the aetiology of post-operative CF drop following arthroplasty is not embolic in nature, or that with current technology MRI brain scans even with angiograms are not sensitive enough to show the corresponding abnormality. With currently available equipment there appears to be no benefit from using MRI as a tool to evaluate post-operative CF loss in this group of patients

Refinement of surgical techniques, anesthesia protocols, and patient selection has facilitated this transformation to same day discharge for arthroplasty care, most notably Partial Knee Arthroplasty (PKA). The trend for early discharge has already happened for procedures formerly regarded as “inpatient” procedures such as upper extremity surgery, arthroscopy, ACL reconstruction, foot and ankle procedures, and rotator cuff repair. Our program began focused on PKA and has now expanded to primary TKA and THA, and select revision cases. Over the past few years we have performed 1,230 knee arthroplasty procedures with no readmissions for pain control. Average age and age range is identical to our inpatient cohort for our partial knee cases. Patient selection is based on medical screening criteria and insurance access. PKA is the ideal procedure to begin your transition to the outpatient space. We currently perform medial PKA, lateral PKA, and patellofemoral arthroplasty as an outpatient. The program centers on the patient, their family, home recovery, preoperative education, efficient surgery, and represents a shift in the paradigm of arthroplasty care. It can be highly beneficial to patients, surgeons, anesthesia, facility costs, and payors as arthroplasty procedures shift to the outpatient space. Perhaps the most significant developments in joint replacement surgery in the past decade have been in the area of multimodal pain management. This has reduced length of stay in the inpatient hospital environment opening the opportunity for cost savings and even outpatient joint replacement surgery for appropriately selected patients. The hallmark of this program is meticulous protocol execution. Preemptive pain control with oral anti-inflammatory agents, gabapentin, regional anesthetic blocks that preserve quad function for TKA (adductor canal block) and pericapsular long acting local anesthetics with the addition of injectable ketorolac and IV acetaminophen are key adjuncts. Over the past two years utilizing this type of program over 60% of our partial knee replacement patients are now returning home the day of surgery. Concerns over readmission are appropriate. The rates of complications and readmissions are less than our inpatient cohort in appropriately selected cases with a standardised care map. We believe this brings the best VALUE to the patients, surgeons, and the arthroplasty system

Refinement of surgical techniques, anaesthesia protocols, and patient selection have facilitated this transformation to same day discharge for arthroplasty care, most notably Partial Knee Arthroplasty (PKR). The trend for early discharge has already happened for procedures formerly regarded as “inpatient” procedures such as upper extremity surgery, arthroscopy, ACL reconstruction, foot and ankle procedures, and rotator cuff repair. Our program began focused on Partial Knee Arthroplasty (PKA) and has now expanded to primary TKA and THA, and select revision cases. Over the past few years we have performed 1,230 Knee Arthroplasty procedures with no readmissions for pain control. Average age and age range is identical to our inpatient cohort for our partial knee cases. Patient selection is based on medical screening criteria and insurance access. PKA is the ideal procedure to begin your transition to the outpatient space. We currently perform medial PKA, lateral PKA, and patellofemoral arthroplasty as outpatient cases. The program centers on the patient, their family, home recovery, pre-operative education, efficient surgery, and represents a shift in the paradigm of arthroplasty care. It can be highly beneficial to patients, surgeons, anaesthesia, facility costs, and payors as arthroplasty procedures shift to the outpatient space. Perhaps the most significant developments in joint replacement surgery in the past decade have been in the area of multimodal pain management. This has reduced length of stay in the inpatient hospital environment opening the opportunity for cost savings and even outpatient joint replacement surgery for appropriately selected patients. The hallmark of this program is meticulous protocol execution. Pre-emptive pain control with oral anti-inflammatory agents, gabapentin, regional anesthetic blocks that preserve quad function for TKA (adductor canal block) and pericapsular long acting local anesthetics with the addition of injectable ketorolac and IV acetaminophen are key adjuncts. Over the past two years utilizing this type of program over 60% of our partial knee replacement patients are now returning home the day of surgery. Concerns over readmission are appropriate. The rates of complications and readmissions are less than our inpatient cohort in appropriately selected cases with a standardised care map. We believe this brings the best VALUE to the patients, surgeons, and the arthroplasty system

Introduction. Knee arthroplasty is one of the most common inpatient surgeries procedures performed every year however complications do occur. Prior studies have examined the impact of insurance status on complications after TJA in small or focused cohorts. The purpose of our study was to utilize a large all-payer inpatient healthcare database to evaluate the effect of patient insurance status on complications following knee arthroplasty. Methods. Data was obtained from the Nationwide Inpatient Sample between 2004 and 2011. Analysis included patients undergoing knee arthroplasty procedures determined by ICD-9 procedure codes. Patient demographics and comorbidities were analyzed and stratified by insurance type. The primary outcome was medical complications, surgical complications and mortality during the same hospitalization. A secondary analysis was performed using a matched cohort comparing patients with Medicare vs private insurance using the coarsened exact matching algorithm. Pearson's chi-squared test and multivariate regression were performed. Results. Overall, 1,352,505 (57.8% Medicare, 35.6% private insurance, 2.6% Medicaid or uninsured, 3.3% Other) patients fulfilled criteria for inclusion into the study. Most were primary total knee arthroplasties (96.1%) with 3.9% revision knee arthroplasties. Multivariate regression analysis showed that patients with private insurance had fewer complications (OR 0.82, p=<0.001) compared to Medicare patients. Similar trends were found for surgical complications and mortality. Patients with Medicare or no insurance had more surgical complications but equivalent rates of medical complications and mortality. The matched cohort showed Medicare and private insurance patients had overall low mortality rates and complication. The most common complication was postoperative anemia, occurring in 16.2% of Medicare patients and 15.3% of patients with private insurance (RR=1.06, p<0.001). Mortality (RR 1.34), wound dehiscence (RR 1.32), CNS, GI complications, although rare, were all statistically more common in Medicare patients (p<0.05) while cardiac complications (RR 0.93, p=0.003) was more common in patients with private insurance. Discussion and Conclusion. This data reveals that patients with Medicare insurance have higher risk of medical complications, surgical complications and mortality following knee arthroplasty. Using a matched cohort to directly compare Medicare and private insurance patients, the risk of postoperative complications were low overall (with the exception of postoperative anemia), but in general were more common in Medicare patients

Patellofemoral complaints are the common and nagging problem after Total Knee Arthroplasty. Crepitus occurs in 5% to over 20% of knee arthroplasty procedure depending on the type of implant chosen. It is caused by periarticular scar formation with microscopic and gross findings indicating inflammatory fibrous hyperplasia. Crepitus if often asymptomatic and not painful, but in some cases can cause pain. Patella “Clunk Syndrome” is less common and represents a when the peripatella scarring is abundant and forms a nodule which impinges and “catches” on the implants intercondylar notch. Patella Clunk was more common with early PS designs due to short trochlear grooves with sharp transition into the intercondylar notch. Clunks are very infrequent with modern PS implants. This Syndrome has been reported in CR implants as well. Thorough debridement of the synovium and scarring at the time of Arthroplasty is thought to reduce the occurrence of crepitus and clunks. Larger patella with better coverage of the cut bone may also be helpful. The diagnosis can be made on history and physical exam. X-rays are also helpful to assess patella tracking. MRI or ultrasound can be used to identify and confirm the diagnosis but this is not mandatory. Painful crepitus and clunk syndrome that fail conservative management of NSAIDS and physical therapy may require surgery. Both crepitus and clunk can be treated with arthroscopic removal of the peripatella scar. Patella maltracking should also be assessed and treated. While recurrence may occur it is uncommon

Introduction. Bone loss management represents one of the most challenging issues for the orthopaedic surgeon. In most cases, stems, structural allograft, TMcones, and sleeves are adequate to allow optimal implant stability and durable fixation. In selected cases of wide metadiaphyseal bone defects, these devices do not provide proper intraoperative stability. In such scenarios, further steps are needed and include complex modular reconstruction, substitution with megaprosthesis (exposing patients at high risk of early failure) or joint arthrodesis that can yield unacceptable results. The aim of this paper is to present early results obtained with a new custom-made implant for complex metadiaphyseal bone defects management in knee revision surgery. By means of case presentations the authors would highlight the possibilities and technical notes of this novel device in complex knee revision surgery. Methods. Since2015, 8 custom-made porous titanium devices were implanted for massive bone defect management in 6 knee arthroplasty revision procedures. Five patients were staged revision for periprosthetic joint infection (PJI) and one patient underwent a staged revision for post-traumatic septic arthritis. Main demographic and surgical data were collected. Clinical (Range of Movement [ROM], Knee Society Score [KSS] and Oxford Knee Score [OKS]), radiological findings and complications were recorded at different time points and statistically evaluated. Mean follow up was 19.5 ± 9.6months. Results. The study group included 4 males and 2 females with a mean age of 63.7 ± 5.5 years and a mean Body Mass Index of 29.3 ± 4.1. Globally, the mean number of previous surgeries was 4.8 ± 2.7. The custom made device was combined with a hinged prosthesis in 5 cases and with a constrained condylar implant in 1 patient. Hybrid fixation was used in all cases. The mean KSS and OKS of the entire population improved significantly from 35.3 ±6.5 and 19.2 ±3.5 preoperatively to 85.8 ±4.0 and 39.3 ±3.1 at the time of last follow-up evaluation (p<0.01). The range of motion improved from 46.7 ±9.8 of mean preoperative flexion and 7.8 ±6.8 of mean preoperative flexion contracture to 93.3 ±10.3 and 1.2 ±2.9 respectively (p<0.01). Radiological analysis showed no migration or implant loosening. No intraoperative or postoperative complication was recorded. One patient required a prolonged antibiotic therapy for positive culture samples of sonication of the retrieved spacer. No implant mismatch between the preoperative planning and the final implant was reported. Conclusion. The presented custom-made implant showed promising early clinical and radiological results. In extremely selected cases, this new device can be considered a safe and effective surgical step between “off the shelf” reconstruction implants and knee substitution with a tumor megaprosthesis. Accurate surgical planning and intraoperative management of soft tissues and residual bone stock are of paramount importance

Aims

The primary aim is to estimate the current and potential number of patients on NHS England orthopaedic elective waiting lists by November 2020. The secondary aims are to model recovery strategies; review the deficit of hip and knee arthroplasty from National Joint Registry (NJR) data; and assess the cost of returning to pre-COVID-19 waiting list numbers.

Background. The combination of patient-specific “just-in-time” implant manufacture and robotic technology has not yet been reported. The robot enables accurate placement of anatomically-matched implants. It should be cost-effective, simplify the procedure, and reduce instrumentation. The aims of this study were to determine whether the procedure was safe, radiographically accurate, and comparable in time and cost to conventional arthroplasty. Methods. All patients over 3 months post-op were included. Component position, orientation and size were determined from CT scans by the surgeon prior to manufacture. The implants were inserted using the Sculptor robot, which is supplied free of cost (Savile Row, Stanmore Implants, UK). Following registration, bone was milled away using a high-speed burr under haptic control of the robot. The implants were cemented and a mobile bearing inserted. Patients were followed up clinically and radiographically. Oxford and EQ-5D scores were obtained. Costs of the implant, instruments, and consumables were calculated and compared to published data for conventional UKA and TKA. Results. 17 patients (7M:10F) have reached 3 months follow-up. Mean age was 67 (range 49–84). Mean “robotic surgical time” was 25 minutes (range 14–39) contributing to a mean tourniquet time of 79 minutes (range 57–105). Median length of stay was 3 days (range 1–8). Post-op radiographs showed satisfactory component position. At a median follow-op of 4 months (range 3–6), mean Oxford score was 32 (range 23–41), and mean EQ-5DVAS was 70 (range 40–90). There were no serious complications. Total cost was £1665 per patient compared with £1334 for conventional UKA and £2620 for TKA. Conclusions. Patient-specific UKA can be made and placed safely, with radiographical accuracy, using a “no-cost” haptic robot. The time taken is comparable to other knee arthroplasty procedures, uses less instrumentation, and costs £1000 less than a typical TKA

Introduction. Despite advances in surgical technique and prosthetics there continues to be a number of patients who are dissatisfied with the results of their knee replacement procedure. The outcome after total knee arthroplasty (TKA) has been reported frequently with use of condition-specific measures, but patient satisfaction has not been well studied. Material and methods. 160 patients who received primary total knee arthroplasty (TKA) were evaluated prospectively to evaluate factors that may be associated with patient satisfaction. At minimum one year follow-up all patients were evaluated and completed validated self-report satisfaction questionnaires. Patient, surgeon, implant and process of care variables were assessed along with WOMAC, Oxford Knee and SF-12 scores. Univariate and multivariate analyses were performed to assess for independent factors associated with post-operative satisfaction. Results. Significant factors associated with post-operative satisfaction include (p<0.05): pre-operative pain and function, presence of comorbidity, post-op complication or stiffness. Age, gender, pre-operative diagnosis, flexion contracture, pre-op range of motion, implant type (fixed vs rotating platform), and surgeon did not significantly affect patient-reported satisfaction (p>0.05). Post-operative function and pain (WOMAC, Oxford Knee Score), comorbidity, and mental status (SF-12 mental) were also highly associated with post-operative satisfaction (p<0.05) at one year post-op. Discussion and conclusion. The primary drivers of patient satisfaction appear to be related to patient-related factors including magnitude of baseline disability and comorbidity as well as the development of any post-op complication. Surgeon and implant related factors do not appear to have a significant effect on satisfaction. Understanding determinants of satisfaction may assist the surgeon and patient when planning for surgery and setting realistic expectations for post-operative outcome

Introduction. Although the “learning curve” in surgical procedures is well recognized, little data exists documenting the accuracy of surgeons in performing individual steps of orthopedic procedures. In this study we have used a validated computer-based training system to measure variations instrument placement and alignment in TKA, specifically those relating to tibial preparation. Methods. Eleven trainees (surgical students, residents and fellows) were recruited to perform a series of 43 knee replacement procedures in a computerized training center. After initial instruction, each trainee performed a series of four TKA procedures in cadavers (n=2) and bone replicas (n=2) using a contemporary TKA instrument set and the assistance of an experienced surgical instructor. The Computerized Bioskills system was utilized to monitor the placement and orientation of the proximal tibial osteotomy and the tibial tray. Results. The tibial component was implanted with an average posterior slope of 3.2°±2.7°. In 14% of cases the tibial resection sloped anteriorly, and in another 5%, the posterior slope exceeded 10°. In 83% of trials, the trainees cut the tibia with less posterior slope than intended, ranging from −10.0° to +5.6° (average:−2.0°±4.0°). The average rotational orientation of the tibial component was 5.4°±5.3°of external rotation, however individual values ranged from 7.6°of int rot to 14.4°of ext rot. Overall, 19% of components were placed in internal rotation. Conclusions. Tibial preparation still presents significant difficulty to many less experienced surgeons, despite the use of modern instrumentation and careful didactic instruction. The errors measured in the computerized bioskills lab unfortunately replicate clinical cases often presenting with symptoms necessitating early revision,. Greater attention is needed to training of surgical skills and intraoperative assessment of component position to improve clinical outcomes of TKA

Introduction:. Despite all the attention to new technologies and sophisticated implant designs, imperfect surgical technique remains a obstacle to improving the results of total knee replacement (TKR). On the tibial side, common errors which are known to contribute to post-operative instability and reduced function include internal rotation of the tibial tray, inadequate posterior slope, and excessive component varus or valgus. However, the prevalence of each error in surgeries performed by surgeons and trainees is unknown. The following study was undertaken to determine which of these errors occurs most frequently in trainees acquiring the surgical skills to perform TKR. Materials and Methods:. A total of 43 knee replacement procedures were performed by 11 surgical trainees (surgical students, residents and fellows) in a computerized training center. After initial instruction, each trainee performed a series of four TKR procedures in cadavers (n = 2) and bone replicas (n = 2) using a contemporary TKR instrument set and the assistance of an experienced surgical instructor. Prior to each procedure, computer models of each cadaver and/or bone replica tibia were prepared by reconstructing CT scans of each specimen. All training procedures were performed in a navigated operating room using a 12 camera motion analysis system (Motion Analysis Inc.) with a spatial resolution in all three orthogonal directions of ± 0.15 mm. The natural slope, varus/valgus alignment, and axial rotation of the proximal tibial surface were recorded prior to surgery and after placement of the tibial component. For evaluation of all data, acceptable limits for implantation were defined as: posterior slope: 0–10°; varus/valgus inclination of tibial resection: ± 3°; and external rotation: 0–10°. Results:. The tibial component was implanted with an average posterior slope of 3.4° ± 3.4°. In 83% of trials, the trainees cut the tibia with less posterior slope than intended (average shortfall: 2.0° ± 4.0°). In 14% of cases the tibial resection sloped anteriorly, whereas in another 5% the posterior slope exceeded 10°. The coronal alignment of the tibial osteotomy averaged 0.1° ± 2.9° of valgus, with 19% of components were implanted in more than 3° of valgus vs. 14% varus (>3°). The average rotational orientation of the tibial component was 5.4° ± 5.3° of external rotation. Overall, 21% of components were placed in internal rotation, and a further 29% in more than 10° of external rotation. Rotational malalignment of the tibial component was the most common error in technique encountered in the study population. Conclusion:. 1. Tibial preparation still presents significant difficulty to many less experienced surgeons, despite the use of modern instrumentation and careful didactic instruction. 2. The most prevalent error in tibial preparation in TKR is malrotation of the tibial component, especially in internal rotation. 3. The errors measured in the computerized bioskills lab replicate clinical cases often presenting with symptoms necessitating early revision. 4. Greater attention is needed to training of surgical skills and intraoperative assessment of sources of technical error, such as component position to improve clinical outcomes of TKR