Total Knee Arthroplasty Cases Research Articles

Leg length discrepancy before total knee arthroplasty is associated with increased complications and earlier time to revision

IntroductionLeg length discrepancy (LLD) following total knee arthroplasty (TKA) is a common complaint, leading to decreased patient satisfaction. However, the effect of LLD diagnosis prior to TKA on outcomes and complications is not well defined. Thus, this study aimed to assess the effects that LLD has on rates of falls and implant complications, length of stay and readmissions, and implant survivorship following TKA.MethodsA retrospective review of a private insurance claims database was conducted from 2010 to 2021. All cases of TKA and those with a diagnosis of leg length discrepancy were identified. Patients undergoing TKA with a diagnosis of LLD were matched to control patients 1:5 based on demographic and comorbidity profiles. Two-year fall rates and implant complications, lengths of stay, 90-day readmissions, and time to revision were compared between cohorts.ResultsA total of 1,378 LLD patients were matched to 6,889 control patients. The LLD group had significantly higher rates of falls, dislocation, mechanical loosening, periprosthetic fracture, and fibrosis when compared to the control group (all P < 0.01). Additionally, mean length of stay was significantly greater in the LLD group (4.9 days vs. 3.0 days, P < 0.001). There was no significant difference in 90-day readmission rates between groups (P = 0.178). Time to revision was significantly shorter in the LLD group (392 days vs. 928 days, P < 0.001).ConclusionsLeg length discrepancy in patients undergoing TKA was associated with significantly increased fall risk, rates of implant complications, length of stay, and faster time to revision. The findings of this study may allow orthopedic surgeons to identify those patients at risk and allow for more educated patient counseling and operative planning.Level of evidenceIII, retrospective case–control study.Graphical

Influencing factors on the quality of recovery after total knee arthroplasty: development of a predictive model.

Total Knee Arthroplasty (TKA) is a widely performed procedure that significantly benefits patients with severe knee degeneration. However, the recovery outcomes post-surgery can vary significantly among patients. Identifying the factors influencing these outcomes is crucial for improving patient care and satisfaction. In this retrospective study, we analyzed 362 TKA cases performed between January 1, 2018, and July 1, 2022. Multivariate logistic regression was employed to identify key predictors of recovery within the first year after surgery. The analysis revealed that Body Mass Index (BMI), age-adjusted Charlson Comorbidity Index (aCCI), sleep quality, Bone Mineral Density (BMD), and analgesic efficacy were significant predictors of poor recovery (p < 0.05). These predictors were used to develop a clinical prediction model, which demonstrated strong predictive ability with an Area Under the Receiver Operating Characteristic (AUC) curve of 0.802. The model was internally validated. The findings suggest that personalized postoperative care and tailored rehabilitation programs based on these predictors could enhance recovery outcomes and increase patient satisfaction following TKA.

Clinical and Biomechanical Evaluation of Mid-Level Constrained and Posterior-Stabilized Polyethylene Inserts in Primary Total Knee Arthroplasty: An Analysis of 12,674 Cases

BackgroundMid-level constraint polyethylene designs provide additional stability in total knee arthroplasty (TKA). The purposes of this study were to (1) compare the survivorship and reason for revision between mid-level inserts and posterior-stabilized (PS) used in primary TKA and (2) evaluate the biomechanical constraint characteristics of mid-level inserts. MethodsWe reviewed all cases of primary TKA performed at our institution from 2016 to 2019 using either PS or mid-level constrained inserts from 1 of 6 manufacturers. Data elements included patient demographics, implants, reasons for revision, and whether a manipulation under anesthesia was performed. We performed finite element analyses to quantify the varus/valgus and axial-rotation constraint of each mid-level constrained insert. A one-to-one propensity score matching was conducted between the patients with mid-level and PS inserts to match for variables, which yielded 2 cohorts of 3,479 patients. ResultsFor 9,163 PS and 3,511 mid-level TKAs, survivorship free from all-cause revision was estimated up to 5 years and was lower for mid-level than PS inserts (92.7 versus 94.1%, respectively, P = .004). When comparing each company’s mid-level insert to the same manufacturer’s PS insert, we found no differences in all-cause revision rates (P ≥ .91) or revisions for mechanical problems (P ≥ .97). Using propensity score matching between mid-level and PS groups, no significant differences were found in rates of manipulation under anesthesia (P = .72), all-cause revision (P = .12), revision for aseptic loosening (P = .07), and revision for instability (P = .45). Finite element modeling demonstrated a range in varus/valgus constraint from ±1.1 to >5°, and a range in axial-rotation constraint from ±1.5 to ±11.5° among mid-level inserts. ConclusionsDespite wide biomechanical variations in varus/valgus and axial-rotation constraint, we found minimal differences in early survivorship rates between PS and mid-level constrained knees.

Improvement of rotational arc during deep flexion range of a novel designed polyethylene insert for posterior-stabilised total knee arthroplasty

BackgroundOne of the remaining issues in total knee arthroplasty (TKA) is achieving sufficient rotational arc during deep flexion range of the knee for specific postures such as the ‘seiza’ or cross-legged sitting. This study aimed to evaluate whether there was a change in the actual in vivo rotational arc during deep flexion range before and after a design change of polyethylene (PE) inserts. MethodsIn 50 posterior-stabilised TKA cases, knee kinematics, including rotational movement, were measured intraoperatively using an image-free navigation system to compare a newly designed PE insert with reduced the posterior lip with a conventional PE insert. Femoral–tibial rotational angles at 30°, 45°, 60°, 90°, 120°, and 130° knee flexion were evaluated. Varus/valgus instability, knee range of motion, and femoral rollback were also measured. Obtained parameters were compared between new and conventional PE inserts. The independent factors associated with rotational arc during deep flexion range (120° and 130° knee flexion) were analysed using multivariate analysis. ResultsThe newly designed PE insert demonstrated a significant increase in the rotational arc at 120° (22.9 ± 8.7° vs. 30.1 ± 11.9°, P < 0.001) and 130° (24.3 ± 9.5° vs. 32.5 ± 12.4°, P < 0.001) knee flexion compared with that with the conventionally designed posterior-stabilised insert. Multivariate analysis demonstrated that using the newly designed PE insert was an independent predictor of improved rotational arc during deep flexion range: regression coefficient was 11.2 (95% confidence interval 7.1–15.3, P < 0.001). ConclusionThe design change, which reduced the posterior lip of the PE insert, contributed to improved rotational arc in 120° and 130° deep flexion ranges.

Analgesic Effect of Intraoperative Intravenous S(+)-Ketamine During Total Knee Arthroplasty Surgery: Study Protocol for a Randomized Controlled Clinical Trial.

Total knee arthroplasty (TKA) is currently the main treatment for end-stage knee disease. The number of cases of TKA in China increased from 53,880 in 2011 to 374,833 in 2019, representing a 5.9-fold increase. Moderate to severe pain often occurs after TKA, which seriously affects postoperative rehabilitation, patient satisfaction, and overall outcome. Multimodal analgesia is considered the ideal solution. Adequate postoperative analgesia can not only reduce pain, opioid consumption, and, consequently, opioid-related adverse events, but can also reduce the length of hospital stay and costs and improve rehabilitation and patient satisfaction. Effective multimodal pain management in the early postoperative period is essential for anesthesiologists. Additional studies have demonstrated that a low-dose intravenous infusion of ketamine can be administered as an adjuvant drug to alleviate acute postoperative pain. Therefore, we aim to appraise the efficacy and safety of intraoperative intravenous injection of S(+)-ketamine to relieve acute pain after TKA in older patients. This is a protocol for a randomized, placebo-controlled trial. A total of 144 participants aged 65 years and older undergoing TKA will be randomly allocated into the S(+)-ketamine and placebo groups in a 1:1 ratio. S(+)-ketamine or the placebo will be intravenously administered at 0.3 mg/kg/h during the operation by anesthesiologists. Blinded evaluation by trained investigators will be completed at 2 hours, 24 hours, and 48 hours after surgery. The primary outcome measure will be the numeric rating scale score at rest and movement at 24 hours after surgery. The secondary outcomes will include the numeric rating scale scores at rest and movement at 2 hours and 48 hours after surgery, the number of patients who require additional analgesics during the first 48 hours after operation, the total consumption of opioids or nonsteroid anti-inflammatory drugs during the first 48 hours after operation, and adverse events at 2, 24, and 48 hours after operation. The protocol was registered at Clinical Trials.gov on February 26, 2022. It was performed in accordance with the approved guidelines and regulations of the participating institutions. Recruitment began in April 2022. Data collection is expected to conclude in September 2024. Study completion is expected in December 2024. A randomized, controlled, clinical study was designed to observe the analgesic effect of intraoperative intravenous administration of a lower dose of S(+)-ketamine (0.3 mg/kg/h) in older patients after TKA surgery. The protocol will appraise the efficacy and safety of intraoperative intravenous injection of S(+)-ketamine to relieve acute pain after TKA in older patients who may benefit from the administration of S(+)-ketamine. ClinicalTrials.gov NCT05289050; https://clinicaltrials.gov/ct2/show/NCT05289050. DERR1-10.2196/53063.

Learning curve analysis of robotic-assisted total knee arthroplasty with a Chinese surgical system

PurposeThe aim of this study was to analyze the learning curve of total operative time, bone cutting accuracy, and limb alignment in total knee arthroplasty (TKA) using a Chinese image-based knee surgery robot known as HURWA. Additionally, a comparison was conducted with conventional TKA to ascertain the benefits of robotic-assisted TKA.MethodsIn this retrospective study, we analyzed a series of patients (n = 90) who underwent robotic-assisted total knee arthroplasty using the HURWA robot between December 2021 and October 2022. The procedures were performed by one of three orthopedic surgeons with varying levels of experience. As a control group, we selected the last 30 conventional TKA cases performed by each of these three surgeons. To determine the learning curve, we recorded the operative time, bone cutting error, and pre- and post-surgery radiographs.ResultsThe study found no significant differences in total operative time, bone cutting accuracy, or limb alignment among the three surgeons. Of the three surgeons, surgeon 1, who had the most experience in joint arthroplasty, reached the learning curve in case 8, with the shortest bone cutting time and robot time. Surgeon 2 reached the learning curve in case 16, while surgeon 3 reached the learning curve in case 9. There was no observable learning curve effect for bone cutting accuracy and limb alignment. However, the percentage of cases where limb alignment differed from preoperative planning by 3° or less was higher in robotic-assisted TKA (77.97%) than in conventional TKA (47.19%).ConclusionThe study determined that the learning curve for robotic-assisted TKA using the HURWA knee surgery robot ranged from 8 to 20 cases. No observable learning curve effect was detected for bone cutting accuracy or limb alignment. Experienced surgeons using the HURWA robot for bone cutting took less time and reached the learning curve earlier. The HURWA robot achieved better limb alignment without depending on the experience of conventional TKA.

The Impact of Social Determinants of Health on Outcomes and Complications After Total Knee Arthroplasty: An Analysis of Neighborhood Deprivation Indices.

Social determinants of health (SDOH) are important factors in the delivery of orthopaedic care. The purpose of this study was to investigate the relationship between outcomes following total knee arthroplasty (TKA) and both the Social Vulnerability Index (SVI) and the Area Deprivation Index (ADI). The Michigan Arthroplasty Registry Collaborative Quality Initiative (MARCQI) database was utilized to identify TKA cases for inclusion. Demographic characteristics and medical history were documented. The SVI, its subthemes, and the ADI were analyzed. Outcome data included length of stay, discharge disposition, postoperative change in the Knee Injury and Osteoarthritis Outcome Score, Joint Replacement (KOOS, JR), 90-day incidences of emergency department (ED) visits, readmission, death, deep venous thrombosis (DVT) and/or pulmonary embolism (PE), periprosthetic fracture, implant failure, periprosthetic joint infection (PJI), and all-cause reoperation. Database cross-referencing was completed to document aseptic and septic revisions beyond 90 days postoperatively. Bivariate quartile-stratified and multivariable analyses were used to associate deprivation metrics with outcomes. A total of 19,321 TKA cases met inclusion criteria. Baseline patient characteristics varied among the SVI and/or ADI quartiles, with patients of non-White race and with a greater number of comorbidities noted in higher deprivation quartiles. Higher SVI and/or ADI quartiles were correlated with an increased rate of discharge to a skilled nursing facility (p < 0.05). A higher SVI and/or ADI quartile was associated with increased incidences of ED visits and readmissions postoperatively (p < 0.05). DVT and/or PE and long-term aseptic revision were the complications most strongly associated with higher deprivation metrics. Upon multivariable analysis, greater length of stay and greater incidences of ED visits, readmissions, DVT and/or PE, and aseptic revision remained significantly associated with greater deprivation based on multiple metrics. Greater deprivation based on multiple SVI subthemes, the composite SVI, and the ADI was significantly associated with increased length of stay, non-home discharge ED visits, and readmissions. The SVI and the ADI may be important considerations in the perioperative assessment of patients who undergo TKA. Prognostic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Using novel porous metal pillars for tibial bone defects in primary total knee arthroplasty

BackgroundThe optimal method to treat tibial bone defects during primary total knee arthroplasty (TKA) is still unclear. A novel technique of porous metal pillar augmentation has been applied recently. This study aimed to assess the short-term outcomes of primary TKA with the use of novel porous metal pillars for tibial bone defects.MethodsA total of 24 cases (22 patients) of primary TKA between January 2019 and December 2020 using porous metal pillars for tibial bone defects were reviewed. Clinical results were evaluated using the Knee Society knee score (KSKS) and function score (KSFS), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and range of motion (ROM). Hip-knee-ankle angle (HKAA), femorotibial angle (FTA), and radiolucent lines were assessed radiologically.ResultsThe median follow-up period was 36.0 months (interquartile range: 31–37 months). The KSKS, KSFS, WOMAC score, and ROM improved significantly at the final follow-up assessment compared with the preoperative evaluation. Both of the HKAA and FTA were corrected after surgery. Only one knee had a nonprogressive radiolucent line at the bone-cement interface. No radiolucent lines were detected around the pillar in any of the cases. There were no cases of prosthesis loosening and revision.ConclusionsThe use of novel porous metal pillars yielded satisfactory clinical outcomes and reliable radiological evidence of fixation in this study with a minimum 2-year follow-up. Porous metal pillar augmentation can be considered as a valuable and easy-to-use method for the management of tibial bone defects in primary TKA.

Effect of posteromedial vertical capsulotomy with medial collateral ligament liberation on intraoperative medial component gap mismatch between extension and mid-flexion during total knee arthroplasty.

The aim of this study was to quantify the effect of posteromedial vertical capsulotomy on intraoperative component gaps and angles from extension through mid-flexion to flexion during total knee arthroplasty (TKA). In the present study, 47 cases of primary posterior-stabilized TKA using the measured resection technique for varus knee osteoarthritis (hip-knee-ankle angles < 0°) were reviewed. Component gaps and angles at 0°, 10°, 45°, 90°, and maximum flexion were measured intraoperatively, before and after posteromedial vertical capsulotomy. Differences in pre- and post-posteromedial vertical capsulotomy medial and lateral component gaps and angles and medial component gap mismatches among knee flexion angles were assessed using the Wilcoxon signed rank test for two paired samples. The medial component gaps at 0° and 10° of flexion of post-posteromedial vertical capsulotomy were significantly greater, exceeding the minimal detectable change, than those pre posteromedial vertical capsulotomy (change of the gap after the procedure at 0° of flexion was 0.7 ± 0.7mm and at 10° of flexion was 0.8 ± 0.8mm; all P values < 0.05). The medial component gap mismatches between both 0° and 10°, and 45°, 90°, and maximum flexion were significantly smaller post posteromedial vertical capsulotomy than pre posteromedial vertical capsulotomy, with the values of the change exceeding the minimal detectable change (change of the gap mismatch after the procedure: knee flexion at 0° and 45° was - 0.6 ± 0.9 [mm], at 0° and 90° was 0.7 ± 1.0, at 0° and maximum flexion was - 0.6 ± 1.2, at 10° and 45° was - 0.7 ± 0.9, at 10° and 90° was - 0.8 ± 0.9, at 10° and maximum flexion was - 0.7 ± 1.1; all P values < 0.05). Posteromedial vertical capsulotomy increased the medial component gaps during knee extension but not during mid-flexion or full flexion during posterior-stabilized TKA. Posteromedial vertical capsulotomy improved mild medial component gap mismatch between extension and mid-flexion and full flexion during posterior-stabilized TKA. Surgeons can consider posteromedial vertical capsulotomy when there is intraoperative constriction of the medial component gap during extension in patients undergoing posterior-stabilized TKA.

The Use of Iodophor-Impregnated Drapes in Patients With Iodine-Related Allergies: A Case Series and Review of the Literature.

The use of iodophor-impregnated adhesive drapes have become almost universally incorporated into standard practice of arthroplasty draping technique. Iodine-related allergies in patients planned for joint replacement present a challenge in terms of the best course of action to minimize complications and optimize outcomes. This is a retrospective case series of patients that received an iodophor-impregnated drape as part of draping for a total hip or knee arthroplasty at a single orthopaedic-specific hospital with documented iodine-related allergies. From 2015 to 2023, 9816 total hip arthroplasty and total knee arthroplasty cases were reviewed, and 135 were documented to have an iodine-related allergy for a prevalence of 1.38%. Intraoperative and postoperative records were reviewed to screen for an allergic reaction or wound healing issues that may have been related to an adverse reaction to the use of the iodophor-impregnated drape. Of the 135 patients, 43 had iodine listed as an allergy, 85 had shellfish, 20 had iodinated contrast media, and 3 had povidone iodine. Sixteen patients had a cluster of iodine-related allergies. There were no intraoperative reports of an allergic reaction to this drape. There were four superficial wound problems, none of which were documented to relate to an allergic dermatitis reaction, and none required further surgery. Patients reporting iodine-related allergies were present in 1.38% of patients undergoing hip or knee arthroplasty in our series. We encountered no allergic reactions or adverse outcomes that could be attributed to the use of iodiphor impregnated drapes in these patients.

Unplanned Emergency Department Visits Following Revision Total Joint Arthroplasty: Incidences, Risk Factors, and Mortalities

BackgroundThe incidence of unplanned emergency department (ED) visits following revision total joint arthroplasty is an indicator of the quality of postoperative care. The aim of this study was to investigate the incidences, timings, and characteristics of ED visits within 90 days after revision total joint arthroplasty. MethodsA retrospective review of 457 consecutive cases, including 254 revision total hip arthroplasty (rTHA) and 203 revision total knee arthroplasty (rTKA) cases, was conducted. Data regarding patient demographics, timings of the ED encounter, chief complaints, readmissions, and diagnoses indicating reoperation were analyzed. ResultsThe results showed that 41 patients who had rTHA (16.1%) and 14 patients who had rTKA (6.9%) returned to the ED within 90 days postoperatively. The incidence of ED visits was significantly higher in the rTHA group than in the rTKA group (P = .003). The most common surgery-related complications were dislocation among rTHA patients and wound conditions among rTKA patients. Apart from elevated calculated comorbidity scores, peptic ulcer in rTHA patients and cerebral vascular events and chronic obstructive pulmonary disease in rTKA patients might increase chances of unplanned ED visits. Patients who had ED visits showed significantly higher mortality rates than the others in both rTHA and rTKA cohorts (P = .050 and P = .008, respectively). ConclusionsThe ED visits within 90 days are more common after rTHA than after rTKA. Patients in both ED visit groups after rTHA and rTKA demonstrated worse survival. Efforts should be made to improve quality of care to prevent ED visits.

Prior COVID-19 and Venous Thromboembolism Risk in Total Joint Arthroplasty in Patients Over 65 Years of Age

BackgroundThe COVID-19 pandemic has been associated with increased risks of venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE). However, there is limited literature investigating prothrombotic states and complications after total hip arthroplasty (THA) and total knee arthroplasty (TKA). We investigated (1) trends in VTE, PE, and DVT rates post-THA and TKA from 2016 to 2019 compared to 2020 to 2021 and (2) associations between prior COVID-19 diagnosis and VTE, PE, and DVT. MethodsA national dataset was queried for elective THA and TKA cases from 2016 to 2021. We first assessed trends in 90-day VTE prevalence between 2016 to 2019 and 2020 to 2021. Second, we investigated associations between previous COVID-19 and 90-day VTE with regression models. ResultsFrom 2016 to 2021, a total of 2,422,051 cases had an annual decreasing VTE prevalence from 2.2 to 1.9% (THA) and 2.5 to 2.2% (TKA). This was evident for both PE and DVT (all trend tests P < .001). After adjusting for covariates (including vaccination status), prior COVID-19 was associated with significantly increased odds of developing VTE in TKA patients (odds ratio 1.2, 95% confidence interval 1.1 to 1.4, P = .007), but not DVT or PE (P > .05). There were no significant associations between prior COVID-19 and VTE, DVT, or PE after THA (P > .05). ConclusionsOur study suggests that a previous diagnosis of COVID-19 is associated with increased odds of VTE, but not DVT or PE, in TKA patients. Ongoing data monitoring is needed given our effect estimates, emerging COVID-19 variants, and evolving vaccination rates.

Resurfacing Versus Non-resurfacing Patella in Total Knee Replacement: When and What to Choose.

The opinion on the necessity of patella resurfacing has been deeply divided in the scientific community. There are three approaches to the management of the patella in total knee arthroplasty (TKA). The first method involves always resurfacing the patella, the second method involves never resurfacing it, and the third method involves resurfacing the patella only under specific circumstances. Different data support each of these strategies, but no consensus on the best management has been reached. This is a retrospective study of 106 cases of TKA (including 29 resurfaced patellas and 77 non-resurfaced patellas), over 5 years, at the Trauma-Orthopedics Department of theCheikh Khalifa International University Hospital, Mohammed VI University of Health Sciences, Casablanca, Morocco. Our objective is to conduct a comparative study between TKA with patella resurfacing and those without resurfacing, by analyzing the functional and radiological results obtained after the operation, to show each technique's advantages and disadvantages. The average age of our patients was 65 years with extremes ranging from 46 to 80 years. There was a clear female predominance with a sex ratio of 0.2. The left side was predominantly affected. Primary gonarthrosis was the main diagnosis. Our results showed no significant difference between the two groups in terms of patient satisfaction and Knee Society Score (KSS). Nevertheless, complications generated by resurfacing, such as infection, anterior pain, stiffness, and loosening of the patellar component, as well as additional costs and increased operative time, were observed. In the majority of meta-analyses, there was no discernible difference in clinical and functional results between the resurfaced and non-resurfaced groups, suggesting that patellar resurfacing is not beneficial and, therefore, unnecessary. It appears that regular resurfacing is not necessary. However, there is agreement that resurfacing the patella is the best course of action for patients with inflammatory arthropathy, considerable patella malalignment, and severe patellofemoral osteoarthritis. There are arguments in favor of each of the patella resurfacing techniques, but none of them are particularly compelling, each of these strategies has itsadvantages and should not be considered bad. The final decision, therefore, rests on each surgeon's practice, training, and experience.

Can machine learning models predict prolonged length of hospital stay following primary total knee arthroplasty based on a national patient cohort data?

The total length of stay (LOS) is one of the biggest determinators of overall care costs associated with total knee arthroplasty (TKA). An accurate prediction of LOS could aid in optimizing discharge strategy for patients in need and diminishing healthcare expenditure. The aim of this study was to predict LOS following TKA using machine learning models developed on a national-scale patient cohort. The ACS-NSQIP database was queried to acquire 267,966 TKA cases from 2013 to 2020. Four machine learning models-artificial neural network (ANN), random forest, histogram-based gradient boosting, and k-nearest neighbor were trained and tested on the dataset for the prediction of prolonged LOS (LOS exceeded the 75th of all values in the cohort). The model performance was assessed by discrimination (area under the receiver operating characteristic curve [AUC]), calibration, and clinical utility. ANN delivered the best performance among the four models. ANN distinguished prolonged LOS in the study cohort with an AUC of 0.71 and accurately predicted the probability of prolonged LOS for individual patients (calibration slope: 0.82; calibration intercept: 0.03; Brier score: 0.089). All models demonstrated clinical utility by generating positive net benefits in decision curve analyses. Operation time, pre-operative transfusion, pre-operative laboratory tests (hematocrit, platelet count, and white blood cell count), and BMI were the strongest predictors of prolonged LOS. ANN demonstrated modest discrimination capacity and excellent performance in calibration and clinical utility for the prediction of prolonged LOS following TKA. Clinical application of the machine learning models has the potential to improve care coordination and discharge planning for patients at high risk of extended hospitalization after surgery. Incorporating more relevant patient factors may further increase the models' prediction strength.

Accuracy and outcome of a handheld accelerometer-based navigation device compared to conventional alignment method in total knee arthroplasty in a Chinese population

Background Total knee arthroplasty (TKA) is a successful procedure in treatment of degenerative disease of the knee, and optimal component placement is essential for long-term implant survival. The purpose of this study was to compare the accuracy of the accelerometer-based KneeAlign 2 (KA2) navigation system against conventional methods for accurate positioning of the femoral and tibial components in TKA in a Chinese population. Methods A total of 123 (37 conventional and 86 KA2) cases of elective primary TKA were reviewed. Hip-knee-ankle (HKA) angle, mechanical lateral distal femoral angle (mLDFA), and anatomical lateral distal femoral angle (aLDFA) were measured from hip-to-ankle EOS radiographs. Accuracy of conventional alignment and KA2 navigation system was assessed by measuring the difference between intraoperative goal and postoperative radiographic measurements of the components for each respective case. Results There was no significant difference between conventional alignment methods and KA2 navigation in achieving a neutral mechanical alignment of the lower limb. KA2 navigation was significantly more accurate than conventional alignment methods for optimal positioning of the tibial component in both the coronal and sagittal plane, while no significant difference between the two groups was appreciated in the positioning of the femoral component in the coronal plane. Conclusions TKA using the accelerometer-based KA2 system was found to offer a high degree of accuracy in component alignment, and in particular, significantly improved tibial component alignment in comparison with conventional alignment methods in a Chinese population. However, no significant improvements were observed in neutral mechanical axis of the lower limb alignment and femoral component placement in the coronal plane.

Mapping the course to recovery: a prospective study on the anatomic distribution of early postoperative pain after total knee arthroplasty

IntroductionEarly postoperative pain following total knee arthroplasty significantly impacts outcomes and patient satisfaction. However, the characteristics and sources of early pain after total knee arthroplasty remain unclear. Therefore, the purpose of this study was to determine the anatomic distribution and course of postoperative pain in the acute and subacute period following total knee arthroplasty.MethodsA prospective observational study of primary, elective unilateral total knee arthroplasty cases was conducted at our academic tertiary care medical center from January 2021 to September 2021. Preoperative variables were extracted from institutional electronic medical records. Postoperatively, patients utilized a knee pain map to identify the two locations with the most significant pain and rated it using the visual analog scale (VAS). The data were collected on day 0, at 2 weeks, 2 months, and 6 months after operation.ResultsThis study included 112 patients, with 6% of patients having no pain at postoperative day 0, 22% at 2 weeks, 46% at 2 months, and 86% at 6 months after operation. In those who reported pain, the VAS score (mean ± standard deviation) was 5.8 ± 2.4 on postoperative day 0 and decreased at each follow-up time point (5.4 ± 2.3 at 2 weeks, 3.9 ± 2.2 at 2 months, and 3.8 ± 2.7 at 6 months). The majority of patients were able to identify distinct loci of pain. The most common early pain loci were patellae, thigh, and medial joint line, and this distribution dissipated by 6 months.ConclusionAt 2 postoperative weeks, pain was primarily at the medial joint, and at 6 months postoperatively, pain was more likely to be at the lateral joint. No relationship was found between pain at six months and pain scores or location at postoperative day 0 or 2 weeks. Understanding the distribution and progression of knee pain following total knee arthroplasty may benefit patient education and targeted interventions.Level of EvidenceLevel II, prospective observational study

Functional Outcome of Above-Knee Amputation After Infected Total Knee Arthroplasty.

Periprosthetic joint infection is a serious complication of total knee arthroplasty (TKA). Management usually involves irrigation and debridement, polyethylene liner exchange, one-stage revision, two-stage revision, knee arthrodesis, or ultimately above-knee amputation (AKA). We present our experience with 21 patients who underwent AKA as a sequela of unresolved infected TKA, highlighting their etiology and functional outcomes. A retrospective chart review was performed for all cases of infected TKA treated with AKA at 1 institute from January 2007 to December 2020, with a minimum follow-up of 1year. Patient demographics, Charlson comorbidity index, culture results, ambulation status, prosthesis fitting, and functional outcomes were collected. Short Form-36 and activities of daily living questionnaires were used for functional outcome assessment. Twenty-one patients were identified, 7 of whom were male (33.3%). Mean ± standard deviation follow-up was 5.7 ± 3.1 years (range, 1-11 years). Mean ± standard deviation age was 57.9 ± 10.7 years (range, 38-87 years), and the mean body mass index was 33.5 ± 6.4 kg/m2 (range, 25.4-46 kg/m2). Gram-positive organisms were identified in 15 cases (66.7%). Prosthesis fitting was successful in 17 patients (81%). Post-AKA ambulation was achieved in 12 patients (57.1%). The ambulating group showed higher Short Form-36 and activities of daily living scores when compared with patients who did not ambulate (60.2 vs 43.3, P= .041, and 67.2 vs 52.7, P= .029, respectively). AKA should be considered solely as the final recourse for infected TKA. Despite the low-to-moderate patient-reported postoperative outcomes, prosthesis fitting and maintaining ambulation can improve postoperative functional outcomes.

The Effect of Surgeon and Hospital Volume on Total Knee Arthroplasty Patient-reported Outcome Measures: An American Joint Replacement Registry Study.

The lower morbidity and mortality rate associated with increased surgeon and hospital volume may also correlate with improved patient-reported outcome measures. The goal of this study was to determine the relationship between surgeon and hospital volume and patient-reported outcome measures after total knee arthroplasty (TKA) using American Joint Replacement Registry data. Using American Joint Replacement Registry data from 2012 to 2020, 8,193 primary, elective TKAs with both preoperative and 1-year postoperative The Knee Injury and Osteoarthritis Outcome Score, Joint Replacement (KOOS-JR) scores were analyzed. This study was powered to detect the minimally clinical important difference (MCID). The main exposure variables were median annual surgeon and hospital volume. Tertiles were formed based on the median annual number of TKAs performed: low-volume surgeons (1 to 52), medium-volume (53 to 114), and high-volume (≥115); low-volume hospitals (1 to 283), medium-volume (284 to 602), and high-volume (≥603). The mean preoperative and 1-year postoperative KOOS-JR were compared. Multivariable logistic regression models were used to determine the effect of surgeon and hospital volume and demographics on achieving the MCID for KOOS-JR. The mean preoperative and 1-year postoperative KOOS-JR score for low-volume surgeons was 47.78 ± 13.50 and 77.75 ± 16.65, respectively, and 47.32 ± 13.73 and 76.86 ± 16.38 for low-volume hospitals. The mean preoperative and 1-year postoperative KOOS-JR score for medium-volume surgeons was 47.20 ± 13.46 and 76.70 ± 16.98, and 48.93 ± 12.50 and 77.15 ± 16.36 for medium-volume hospitals. The mean preoperative and 1-year postoperative KOOS-JR scores for high-volume surgeons were 49.08 ± 13.04 and 78.23 ± 16.72, and 48.11 ± 13.47 and 78.23 ± 17.22 for high-volume hospitals. No notable difference was observed in reaching MCID for KOOS-JR after adjustment for potential confounders. An increased number of TKA cases performed by a given surgeon or at a given hospital did not have an effect on achieving MCID for KOOS-JR outcomes.

Water-Tight Arthrotomy Joint Closure of Modified Intervastus Approach in Total Knee Arthroplasty.

The joint closure technique used for total knee arthroplasty cases can have an impact on outcomes, especially when considering accelerated rehabilitation programs that follow surgery. In this study, we describe the details of the technical steps involved in performing the water-tight arthrotomy joint closure technique that we developed and use. A total of 536 patients (average age: 62 years, average body mass index: 34 kg/m2) with primary osteoarthritis of the knee underwent total knee arthroplasty using the modified intervastus approach between 2019 and 2021. We used the water-tight arthrotomy joint closure technique to close the knee arthrotomy incision. Any infections and complications, as well as the duration of surgery and cost related to this wound closure technique, are also reported. Few complications were noted with this closure technique. When we first started using it, there was one case of drainage through the proximal capsular repair which required a return to the operating room 5 days postoperatively for an irrigation and debridement. We also had two cases of superficial skin necrosis along a small part of the incision line which were observed on a weekly basis and which healed uneventfully with application of betadine once daily on the necrotic area. The average time for performing wound closure after total knee arthroplasty was 45 min. We conclude that the water-tight closure approach can achieve very durable, water-tight capsule repairs and results in a decrease in postoperative wound drainage.

THE ENVIRONMENTAL IMPACT AND SUSTAINABILITY OF TOTAL HIP AND KNEE ARTHROPLASTY

The National Health Service produces over 500,000 tonnes of waste and 25 mega tonnes of CO2 annually. Operating room waste is segregated into different streams which are recycled, disposed of in landfill sites, or undergo costly and energy-intensive incineration processes.By assessing the quantity and recyclability of waste from primary hip and knee arthroplasty cases, we aim to identify strategies to reduce the carbon footprint of arthroplasty surgery.Data was collected prospectively at a tertiary orthopaedic hospital, in the theatres of six arthroplasty surgeons between April – July 2022. Fifteen primary total hip arthroplasty (THA) and 16 primary total knee arthroplasty (TKA) cases were included; revision and complex primary cases were excluded.Waste was categorised into non-hazardous waste, hazardous waste, recycling, sharps, and linens. Each waste category was weighed. Items disposed as non-hazardous waste were catalogued for a sample of 10 TKA and 10 THA cases. Recyclability of items was determined from packaging.Average total waste generated for THA and TKA were 14.46kg and 17.16kg respectively, with TKA generating significantly greater waste (p &lt; 0.05).On average only 5.4% of waste was recycled in TKA and just 2.9% in THA cases. The mean recycled waste was significantly greater in TKA cases compared to THA, 0.93kg and 0.42kg respectively (p &lt; 0.05).Hazardous waste represented the largest proportion of the waste streams for both TKA (69.2%) and THA (73.4%). On average TKA generated a significantly greater amount (11.87kg) compared to THA (10.61kg), p &lt; 0.05.Non-hazardous waste made up 15.1% and 11.3% of total waste for TKA and THA respectively.In the non-hazardous waste, only two items (scrub brush packaging and sterile towel packaging) were identified as recyclable based on packaging.We estimate that annually total hip and knee arthroplasty generates over 2.7 million kg of waste in the UK. Through increased use of recyclable plastics for packaging, combined with clear labelling of items as recyclable, medical suppliers can significantly reduce the carbon footprint of arthroplasty. Our data highlight only a very small percentage of waste is recycled in total hip and knee arthroplasty cases.