Success Of Total Knee Arthroplasty Research Articles

Enhancing total knee arthroplasty outcomes: the role of individualized femoral sagittal alignment in robotic-assisted surgery - A randomized controlled trial

BackgroundOptimal sagittal alignment of the femoral prosthesis is critical to the success of total knee arthroplasty (TKA). While robotic-assisted TKA can improve alignment accuracy, the efficacy of default femoral alignment versus individualized alignment remains under scrutiny. This study aimed to compare the differences in prosthetic alignment, anatomical restoration, and clinical outcomes between individualized femoral sagittal alignment and default sagittal alignment in robotic-assisted TKA.MethodsIn a prospective randomised controlled trial, 113 patients (120 knees) underwent robotic-assisted TKA were divided into two groups: 61 with individualized femoral flexion (individualized alignment group) and 59 with default 3–5° flexion (default alignment group). The individualized alignment was based on the distal femoral sagittal anteverted angle (DFSAA), defined as the angle between the mechanical and distal anatomical axes of the femur. The radiographic and clinical outcomes were compared.ResultsDespite similar postoperative femoral flexion angles between groups (P = 0.748), the individualized alignment group exhibited significantly lower incidences of femoral prosthesis extension and higher rates of optimal 0–3° prosthesis flexion (9.8% vs. 27.1%, P = 0.014,78.7% vs. 55.9%, p = 0.008, respectively). The individualized alignment group also demonstrated more favourable changes in sagittal anatomy, with higher maintenance of postoperative anterior femoral offset within 1 mm (54.1% vs. 33.9%, P = 0.026) and posterior condylar offset within 1 mm and 2 mm (44.3% vs. 25.4%, p = 0.031,73.8% vs. 50.8%, p = 0.010, respectively). Although slight improvement in the Hospital for Special Surgery Knee Score (HSS) at three months was observed (P = 0.045), it did not reach a minimal clinically important difference.ConclusionIndividualized tailoring of femoral sagittal alignment in robotic-assisted total knee arthroplasty (TKA) enhances prosthetic alignment and anatomical restoration, suggesting potential improvements in postoperative outcomes.

KNEE DEFORMITIES AND KNEE REPLACEMENTS IN SAUDI POPULATION: OUR EXPERIENCE AND LITERATURE REVIEW

It takes precise alignment, adequate balance, and deformity correction to accomplish a successful total knee arthroplasty (TKA). In main TKA, this can be successfully achieved with a posterior stabilized (PS) design, either with or without sub-periosteal release. However, severe abnormalities with a major bone defect, stiffness, and instability are often associated with these disorders in some circumstances, such as knee osteoarthritis. Additional restrictive prostheses are required since it is extremely difficult to balance these anomalies with soft tissue release alone, even after main TKA. In this situation, the constrained condylar knee (CCK) design is the optimum choice. This studys primary objectives were to characterize the clinical outcomes, function recovery, and complications of patients who underwent primary CCK-TKA for severe knee osteoarthritis related knee deformity. The secondary aim was to find out the mid-term prostheses survival. Methods: Between March 2021 and March 2022, 36 consecutive patients with knee osteoarthritis had cemented primary CCK-TKA. Twenty-Eight women and eight men, totaling 36 patients, had at least a 6 month follow-up for this retrospective analysis. We used the Knee Society Score (KSS), the Hospital for Special Surgery (HSS) score, and the roentgenographic evaluation form to assess the patients. The survival of prosthesis was assessed using Kaplan-Meiers survival analysis. The patients follow-up periods averaged 12 month. The KSS knee score rose from 44 points (23–68) to 91 points (76–100) following surgery [P < 0.001]. Following the procedure, the mean KSS functional score rose from 20–75 points to 91 points (65–100) [P < 0.001]. The average HSS score rose from 51 points (27–83) to 91 points (75–100) following surgery [P < 0.001]. The average range of motion (ROM) also increased after surgery, going from 68.09° ± 35.99° (0°–120°) to 113.68° ± 8.90° (100°–130°) [P < 0.001]. The average hip-knee-ankle (HKA) angle was 180.24° ± 1.77° (175°–184°) following surgery, compared to 176.88° ± 14.48° (135°–199°) before to surgery. Radiolucencies were seen in thirteen knees, mostly on the tibial side. After an average follow-up of 12 month, 94.7% of prosthesis were still in use. Despite severe deformity, instability, and stiffness at a relatively young age, the mid-term follow-up of primary CCK-TKA in knee osteoarthritis gives satisfactory clinical and functional outcomes with 94.7% prosthesis survival. However, there are a few issues.

Comparison of the coverage and rotation of asymmetrical and symmetrical tibial components: a systematic review and meta-analysis

BackgroundAn optimized fit of the tibial component to the resection platform and correct rotational alignment are critical for successful total knee arthroplasty (TKA). However, there remains controversy regarding the superiority of symmetric tibial component versus asymmetric tibial component. The objective of this systematic review and meta-analysis was to evaluate the current evidence for comparing the coverage and rotation of asymmetrical and symmetrical tibial component.MethodsWe searched potentially relevant studies form PubMed, Web of science, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and China National Knowledge Infrastructure (CNKI), up to 1 March 2023. Data extraction and quality assessment were performed by two independent reviewers. Meta-analysis was conducted using Review Manager 5.4.ResultsSixteen articles were identified. Compared to symmetric tibial component, asymmetric tibial component increased the coverage of the proximal tibial cut surface (MD, -2.87; 95%CI, -3.45 to -2.28; P < 0.00001), improved the prevalence of tibial baseplate underhang (OR, 0.16; 95%CI, 0.07 to 0.33; P < 0.00001) and malrotation (OR, 0.13; 95%CI, 0.02 to 0.90; P = 0.04), and reduced the degree of tibial component rotation (MD, -3.11; 95%CI, -5.76 to -0.47; P = 0.02). But there was no statistical significance for improving tibial baseplate overhang (OR, 0.58; 95%CI, 0.08 to 3.97; P = 0.58). Additionally, no revision had occurred for the two tibial components in the included studies.ConclusionThe current evidence shows asymmetric tibial component offer advantages in terms of coverage and rotation compared with symmetric tibial component in TKA.

The Long-term Efficacy of Total Knee Arthroplasty on End-stage Kashin-Beck Disease of the Knee in Highland Tibetan Areas Patients: A Retrospective Study with 10-Year Follow-up.

Despite the established success of total knee arthroplasty (TKA) with end-stage osteoarthritis, there is a notable scarcity of research on its long-term outcomes in individuals suffering from end-stage Kashin-Beck disease (KBD). This retrospective study aimed to assess the long-term outcomes and effectiveness of clinical function, quality of life, and complications of TKA and end-stage KBD patients in Tibetan highland areas. The retrospective cohort included 43 KBD patients, comprising a total of 59 knees, who had undergone TKA at West China Hospital, Sichuan University between 2008 and 2021. Patients were subsequently followed up for a minimum of 3 years, and received rigorous radiological and clinical assessments at 3, 6, and 12 months post surgery, followed by annual examinations thereafter. The evaluation included various efficacy indices, including visual analogue scale (VAS) scores, hospital for special surgery (HSS) scores, functional score for adult Tibetans with Kashin-Beck disease (FSAT-KBD), and radiographic findings. Comparison of indicators within the same group was conducted using one-way repeated-measures analysis of variance or paired sample t-tests, whereas between-group differences were compared using an independent t-test. Throughout the average follow-up duration of 10.8 years, patients experienced a substantial reduction in knee pain and noteworthy functional improvement. The VAS scores decreased significantly from 77.47 ± 4.12 mm before surgery to 10.91 ± 1.97 mm after surgery, indicating considerable alleviation of knee pain. The HSS scores improved markedly, increasing from 44.26 ± 4.95 preoperatively to 91.26 ± 4.37, indicating enhanced joint function. Similarly, the FSAT-KBD exhibited positive progression, increasing from 25.90 ± 3.12 to 36.95 ± 3.54. Importantly, at the last follow-up, none of the patients presented with periprosthetic infection, prosthesis loosening, or periprosthetic fracture. At long-term follow-up, compared with patients in the preoperative period, patients in Tibetan highland areas with KBD of the knee who underwent TKA benefited from a significant reduction in pain, improvement in joint function, and satisfactory improvement in quality of life.

Comparing Metabolic Preconditioning and Diabetes As Risk Factors in Knee Arthroplasty Complications.

Advanced osteoarthritis of the knee joint severely affects the patient's mobility, compounded by pre-existing comorbidities such as metabolic preconditioning (such as obesity, dyslipidemia, hyperuricemia, and insulin resistance syndrome) and both type I and type II diabetes. The success of total knee arthroplasty is influenced by knowledge and management of risk factors. The present study aims to evaluate differences in the evolution of risk factors such as obesity, injuries, and sedentary lifestyle, distinguishing those with metabolic preconditions and diabetes. The objectives of our study include (1) investigating the prevalence of obesity among patients, highlighting their proportion in the five categories of body weight; (2) analyzing statistically significant differences between research groups in terms of weight status and physical activity; (3) evaluating postoperative evolution based on the administration of nonsteroidal anti-inflammatory drugs (NSAIDs) and without NSAIDs (N-NSAIDs), with an emphasis on overweight patients and those with diabetes; and (4) examining changes in metabolic preconditioning and the incidence of postoperative injury depending on the administration of anti-inflammatory drugs. A cohort involving 730 patients diagnosed with gonarthrosis was divided into two groupsaccording to the administration of anti-inflammatory drugs in the first seven postoperative days:N-NSAIDs group (394 patients, 55.3%)and respectively NSAIDs group (319 patients, 44.7%). Theprospective, observational study was conducted in terms ofrisk factors and complications that occurred upon treatment administration in relation to each type of intervention andimplant used. The outcomes were assessed in terms of the influence on quality of life, the data beingcollected and interpreted for the entire cohort, and for each study year individually. The results indicate that almost 69% of them were overweight, while only 31% had a normal weight. Significant differences in weight status were observed between research groups, highlighting the association between obesity and metabolic preconditions or diabetes. Physical activity was absent in a significant proportion, having a notable impact on postoperative evolution, especially in the group without metabolic precondition. Administration of anti-inflammatory drugs influenced postoperative outcomes, with significant differences in overweight and diabetic patients. The findings suggest the need to manage body weight, promote physical activity, and personalize postoperative treatments, given the complex interactions between obesity, metabolic preconditions, and the administration of NSAIDs.

Opioid reduction and enhanced recovery in orthopaedic surgery (OREOS): a protocol for a feasibility randomised controlled trial in patients undergoing total knee arthroplasty

BackgroundKnee arthritis is a leading cause of limited function and long-term disability in older adults. Despite a technically successful total knee arthroplasty (TKA), around 20% of patients continue to have persisting pain with reduced function, and low quality of life. Many of them continue using opioids for pain control, which puts them at risk for potential long-term adverse effects such as dependence, overdose and risk of falls. Although persisting pain and opioid use after TKA have been recognised to be important issues, individual strategies to decrease their burden have limitations and multi-component interventions, despite their potential, have not been well studied. In this study, we propose a multi-component pathway including personalized pain management, facilitated by a pain management coordinator. The objectives of this pilot trial are to evaluate feasibility (recruitment, retention, and adherence), along with opioid-free pain control at 8 weeks after TKA.MethodsThis is a protocol for a multicentre pilot randomised controlled trial using a 2-arm parallel group design. Adult participants undergoing unilateral total knee arthroplasty will be considered for inclusion and randomised to control and intervention groups. Participants in the intervention group will receive support from a pain management coordinator who will facilitate a multicomponent pain management pathway including (1) preoperative education on pain and opioid use, (2) preoperative risk identification and mitigation, (3) personalized post-discharge analgesic prescriptions and (4) continued support for pain control and recovery up to 8 weeks post-op. Participants in the control group will undergo usual care. The primary outcomes of this pilot trial are to assess the feasibility of participant recruitment, retention, and adherence to the interventions, and key secondary outcomes are persisting pain and opioid use.DiscussionThe results of this trial will determine the feasibility of conducting a definitive trial for the implementation of a multicomponent pain pathway to improve pain control and reduce harms using a coordinated approach, while keeping an emphasis on patient centred care and shared decision making.Trial registrationProspectively registered in Clinicaltrials.gov (NCT04968132).

Establishing the Minimally Important Difference for the KOOS-Joint Replacement and PROMIS Global-10 in Patients After Total Knee Arthroplasty.

Despite the overall prevalence and success of total knee arthroplasty (TKA), a significant portion of patients are dissatisfied with their outcomes. To assess the responsiveness and determine the minimally important difference (MID) of 2 patient-reported outcome measures (PROMs)-the Knee injury and Osteoarthritis Outcome Score-Joint Replacement (KOOS-JR) and the Patient-Reported Outcomes Measurement Information System Global-10 (PROMIS 10)-in patients after TKA. Cohort study (diagnosis); Level of evidence, 3. Included were patients who underwent TKA from August 2015 through August 2019 and completed baseline and postoperative KOOS-JR and PROMIS 10 surveys. The PROMIS 10 consists of 2 domains: physical health and mental health. Estimates for the reliable change index (RCI) and MID, using anchor-based and distribution-based methods, were calculated for each PROM. Regression modeling was used to determine whether patient and clinical factors predicted MID thresholds or MID achievement. A total of 1315 patients were included. Distribution-based MIDs, calculated using various methods from baseline scores, ranged from 19.3 to 31 for the KOOS-JR, and the RCI was 4.38. Of these patients, 293 (22.3%) demonstrated small or moderate improvement, and this cohort was included in the calculation of anchor-based MIDs. The anchor-based MIDs were 16.9 and 24.3 at 3-month and 1-year follow-up, respectively, and 66% of patients achieved the MID at 12 months. Higher preoperative PROM score, male sex, non-White race, and current smoker status were predictive of failing to achieve the anchor-based MID for KOOS-JR at 1 year postoperatively (P < .05). Higher preoperative PROM score and any 90-day adverse event predicted lower thresholds of important change in anchor-based MIDs. Higher baseline PROM scores, younger age, male sex, non-White ethnicity, higher American Society of Anesthesiologists classification, preoperative narcotics use, not smoking, and longer hospital stay were all associated with lower odds of achieving the MID on the KOOS-JR or either of the PROMIS 10 subscales. The study results demonstrated relevant values for interpretation of the KOOS-JR and PROMIS 10. While patient demographics did not accurately predict which patients would achieve the MID, some potential factors predicting successful patient-reported outcomes after TKA were identified.

Knee

The February 2024 Knee Roundup360 looks at: Do patients with hypoallergenic total knee arthroplasty implants for metal allergy do worse? An analysis of healthcare utilizations and patient-reported outcome measures; Defining a successful total knee arthroplasty; Incidence, microbiological studies, and factors associated with periprosthetic joint infection after total knee arthroplasty; A modified Delphi consensus statement on patellar instability; Cause for concern? Significant cement coverage in retrieved metaphyseal cones after revision total knee arthroplasty; Prevalence of post-traumatic osteoarthritis after anterior cruciate ligament injury remains high despite advances in surgical techniques; Cost-effectiveness of arthroscopic partial meniscectomy versus physical therapy for traumatic meniscal tears in patients aged under 45 years.

Correction of Coronal Deformity and Intercompartmental Imbalance through Bone Resection.

This review discusses the correction of coronal deformity and intercompartmental imbalance through bone resection in total knee arthroplasty (TKA). To achieve functional knee balance, coronal, rotational, and sagittal alignment are critical to successful patient outcomes. Though variations in coronal alignment are debated as a correlate to positive results, advancements in utilizing implant position, alignment, and soft tissue balance to improve patient outcomes and function are an evolving discussion. This study draws upon existing literature, clinical studies, and surgical techniques related to TKA, including advancements in navigation and robotics. The study highlights the importance of individualized alignment strategies for varus and valgus knees. While mechanical neutral alignment has shown excellent long-term data, reevaluating the anatomic recreation of the patient's joint line obliquity is now being studied extensively. Sensor data and navigation systems contribute to improved outcomes and patient satisfaction. The evolution of navigation and robotics has led surgeons to achieve their target angles consistently and accurately; now, the discussion is around the most effective alignment targets. The classification of various phenotypes assists in the proposed starting points for implant position, but soft tissue tension is required in the input data to achieve global balance and stable motion. Each approach's advantages and limitations are considered. In conclusion, achieving optimal coronal alignment, joint line obliquity, and soft tissue balance is crucial for successful TKA outcomes. Personalized alignment philosophies, supported by three-dimensional data and sensor technology, are evolving to minimize critical errors and enhance functional results. Robotic assistance and future advancements in artificial intelligence and machine learning hold promise for further improving TKA outcomes in the quest for soft tissue stabilization.

Residual varus alignment after posterior-stabilized total knee arthroplasty limits medial soft tissue remodeling

BackgroundProper lower limb alignment and soft tissue balance are significant indicators to measure the success of total knee arthroplasty (TKA). Previous studies have confirmed that soft tissue relaxation around the knee after TKA will change over time; however, the relationship between lower limb alignment and soft tissue balance after TKA remains unclear. We studied (1) whether the change of soft tissue balance around the knee with time after posterior-stabilized (PS) TKA would affect the alignment of the lower limbs; (2) Whether the accuracy of lower limb alignment during PS TKA affects postoperative soft tissue remodeling.MethodsIn this study, 100 patients were recruited after PS TKA. Among them, 50 patients with a hip knee ankle (HKA) angle of ≤ ± 3° were set as the neutral group, and 50 patients with an HKA angle of > ± 3° were set as the deviation group. The imaging results measured the HKA angle before the operation as well as the HKA, varus, and valgus angles at 1, 3, 6, 12, and 24 months after TKA. Clinical assessment included range of motion (ROM), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Knee Society Score (KSS).ResultsEight people were excluded from the study. After the exclusion, the study enrolled 47 patients in the neutral group and 45 patients in the deviant group and were followed for up to 2 years. There was no statistical significance in mean varus angles as well as HKA angle changes during the follow-up phase of each groups (P > 0.05). The mean valgus angles of the patients in the neutral group group were 2.47°, 3.45°, 3.63°, 3.60° and 3.63°, and in the deviation group were 2.45° (P = 0.841), 2.88° (P < 0.001), 3.07° (P < 0.001), 3.06° (P < 0.001), and 3.10° (P < 0.001). ROM, WOMAC and KSS of the two groups were significantly improved after operation, with no difference between the two groups.ConclusionThis study shows that whether the alignment is accurate or not in the early stage after TKA, the relaxation of the medial and lateral soft tissues of the knee joint change; however, this change will not significantly affect the alignment of the lower limbs. Postoperative residual varus deformity limits medial soft tissue remodeling.Level of evidenceIII.

Preserving primary medial static stabilizer ligaments achieves physiological knee kinematics in total knee arthroplasty

PurposeAs postoperative knee instability has been reported to be one of the critical reasons for early failure in total knee arthroplasty (TKA), obtaining optimal knee stability—especially in medial—was indispensable for successful TKA. We hypothesized that preserving medial soft tissue structures was the key to maintain physiological medial knee stability. Thus, TKAs with preserving primary medial static stabilizer ligaments technique were performed, and the postoperative knee kinematics was evaluated. MethodsPrimary knee osteoarthritis patients with varus knee deformity and planed for primary TKA were enrolled. However, patients with severe varus knee deformities, valgus knee deformities, and rheumatoid arthritis were excluded. TKAs were performed by removing medial femoral and tibial osteophytes; however, the primary medial static stabilizer ligaments—the superficial medial collateral ligament (MCL), deep MCL, and posterior oblique ligament—were not released. The cruciate-retaining (CR), posterior-stabilized (PS), and medial-pivot (MP) inserts were implanted, and the knee kinematics was measured. These data were statistically analyzed using analysis of variance. The institutional review board approved the study. ResultsFrom full extension to maximum flexion, the lateral femoral condyle moved backward, greater than the medial femoral condyle, and consequently the femur external rotated on the tibia. These kinematics patterns were shown in CR, PS, and MP groups. ConclusionAs the knee kinematics of CR and PS are similar to that of MP, which has been reported to demonstrate physiological knee kinematics, preserving primary medial static stabilizer ligaments technique could potentially preserve physiological knee kinematics.

Using sequential bone cutting to titrate soft tissue balance in total knee arthroplasty effectively minimizes soft tissue release

BackgroundAchieving soft tissue balance while maintaining limb alignment within acceptable boundaries is crucial for successful total knee arthroplasty (TKA). We proposed a sequential bone cutting (SBC) technique to titrate the soft tissue balance in robot-assisted TKA to achieve the desired balance with minimum soft tissue release.MethodsIn total, 106 robot-assisted TKAs using the SBC technique were included. The preoperative hip-knee-ankle angle (HKA) was < 10° in 76 and ≥ 10° in 30 knees. The gaps were initially balanced with the help of the pre-resection balancing provided by the robotic system. Soft tissue balance and alignment were quantitatively measured after the initial bone cutting and final bone cutting. Additional adjustments (bone recuts and soft tissue releases) required to address soft tissue imbalance after initial bone cutting were recorded. The frequencies of soft tissue releases, soft tissue balance, and resultant alignment ≤ 3° were compared between non-severe (HKA < 10°) and severe deformity (HKA ≥ 10°) groups.ResultsSoft tissue balance was achieved in 45 knees (42.5%) after initial bone cutting and in 93 knees (87.7%) after final balancing. The postoperative alignment was within 3° from neutral in 87 knees (82.1%) and 3–5° in 17 knees (16.0%). For unbalanced knees (n = 61) after initial bone cutting, soft tissue release was avoided by SBC in 37 knees (60.7%) and was deemed necessary in 24 knees (39.3%). Soft tissue release was more likely to be avoided in the non-severe deformity cohort (86.8% [33 of 38]) than in the severe deformity cohort (17.4% [4 of 23]; p < 0.001). The non-severe deformity cohort showed a significantly higher rate of resultant alignment ≤ 3° from neutral than the severe deformity cohort (90.8% vs. 60.0%; p < 0.001).ConclusionPre-resection balancing is inappropriate to ensure soft tissue balance. The SBC technique is effective in minimizing soft tissue release while maintaining overall alignment within acceptable boundaries.

Total Knee Arthroplasty in the Valgus Knee.

An estimated 10 to 15% of total knee arthroplasties (TKAs) are implanted for a diagnosis of arthritis when a valgus deformity is present. There are various techniques and considerations that must be considered for a successful TKA in a patient with a valgus deformity. This article provides a detailed summary of the anatomy, pathology, bone preparation, soft tissue management, implant selection, and complications when performing a TKA in a patient with valgus deformity.

Short-term clinical outcomes of primary total knee arthroplasty with a new-type kinematic retaining implant: A comparison with preexisting cruciate retaining prosthesis.

Despite the success of total knee arthroplasty (TKA), current implant designs could not consistently restore the physiological knee kinematics, especially in cruciate-retaining (CR) implants. This study aimed to investigate the short-term clinical outcomes, particularly patient satisfaction, of primary TKA employing a new-type kinematic retaining (KR) implant. We analyzed 149 cases applied the KR implant at our institutions during June 2017 to May 2019. The effectiveness of this implant design was compared with another CR one (171 cases). Both groups underwent primary TKA in the same period and all patients completed 2 years of follow-up. Perioperative changes in range of motion (ROM), Knee Score, function score, and patient satisfaction by Forgotten Joint Score-12 (FJS-12) method were evaluated. Postoperative ROM, Knee Score, and function score were significantly improved at 1 year after surgeries and maintained for another year in both KR and CR groups. The improvement rate of ROM in KR group (108.1%) was substantially higher than that in CR (104.5%), even 4% increase could have affected patients' satisfaction in a real-world setting. Regarding the patient satisfaction, such 4 items as climbing stairs, walking on a bumpy road, doing housework or gardening, and taking a walk or hiking were significantly enhanced in KR cases compared to CR. There were no loosening or revision cases and the short-term survivorships of both implants were 100%. In addition, there has been no case of obvious complications in both groups during and after surgeries. The results of the present study suggest that this novel KR prosthesis can reproduce physiological knee kinematics, recover its functions, and contribute to pain relief after TKA. TKA procedure using the KR implant should be a good surgical option to improve postoperative outcomes.

Anterior Knee Pain After Total Knee Arthroplasty: A Critical Review of Peripatellar Variables.

» Despite the widespread success of total knee arthroplasty (TKA), postoperative anterior knee pain (AKP) remains a common occurrence and source of dissatisfaction with several readily discernible and diagnosable causes of AKP after TKA, including component malpositioning, infection, wear and osteolysis, instability, and loosening, among others.» In the setting of the well-appearing but painful TKA, potential intraoperative contributors to AKP have been extensively investigated, but remain controversial and include patellar resurfacing, patellar denervation, and patellofemoral joint overstuffing or understuffing.» Intraoperative management of peripatellar soft tissues has comparatively attained substantially less attention recently, and persistent controversy exists in the literature to make informed decisions on soft-tissue management and identify potential contributors to AKP.» Further investigations and research is needed, including exploration of multifactorial or alternative etiologies, specifically ones related to less obvious soft-tissue-related factors, needed to better understand and ultimately avoid AKP after TKA.

Incidence of soft tissue releases in robotic assisted cementless TKA with mechanical alignment and flexion gap balancing

BackgroundTo ensure the success of total knee arthroplasty (TKA), precise bone cuts and a well-balanced soft tissue envelope are crucial. Soft tissue release may be necessary, subject to various factors. Therefore, documenting the type, frequency, and necessity of soft tissue releases can establish a benchmark for comparing different alignment techniques and philosophies and evaluating their outcomes. The purpose of this study was to demonstrate that robotic-assisted knee surgery requires minimal soft tissue release.MethodsWe prospectively documented and retrospectively reviewed the soft tissue releases employed in securing ligament balance in the first 175 patients who received robotic-assisted TKAs at Nepean Hospital. ROSA was utilized in all surgeries with the aim of restoring mechanical coronal alignment, with a flexion gap balancing technique. Surgeries were performed between December 2019 to August 2021 by a single surgeon who used a standard medial parapatellar approach without a tourniquet, and the cementless persona prosthesis. All patients were followed up for a minimum of 6 months post-surgery. Soft tissue releases included any form of medial release for varus knee, posterolateral release for valgus knee and PCL fenestration or sacrifice.ResultsThere were 131 female and 44 male patients, aged between 48 to 89 years (average 60 years). The preoperative HKA ranged from 22 degrees varus to 28 degrees valgus, with 71% of patients presenting with a varus deformity. For the whole group, the no need for soft tissue release was documented in 123 patients (70.3%), small fenestrated releases of PCL in 27 (15.4%), sacrifice of PCL in 8 (4.5%), medial releases in 4 (2.3%) and posterolateral releases in 13 (7.4%). In 29.7% of patients in whom a soft tissue release was necessary for balance, over half were/received minor fenestrations of the PCL. Outcomes to date included no revisions or impending revisions, 2 MUAs (1%), and Oxford knee scores averaged 40 at 6 months.ConclusionWe concluded that Robot technology enhanced the precision of bone cuts and allowed for titration of required soft tissue releases to achieve optimal balance.

Robotic technology in total knee arthroplasty.

Key factors for successful total knee arthroplasty include accurate implant positioning with precise tibial and femoral resection, combined with appropriate soft tissue balancing to achieve the desired alignment. Robotic-assisted total knee arthroplasty allows surgeons to execute pre-planned strategies with precision, with growing evidence suggesting that robotic-assisted-total knee arthroplasty reduces radiological outliers. This has yet to be proven to translate into long-term improvements in patient-reported outcomes and implant survivorship. Robotic-assisted-total knee arthroplasty systems can be divided into fully autonomous and semi-autonomous systems. While fully autonomous systems showed initial promise, semi-autonomous systems are gaining popularity with encouraging early outcomes suggesting improved radiological and clinical outcomes, although concerns remain regarding a significant learning curve, installation costs, radiation exposure and cost associated with preoperative imaging. The future of total knee arthroplasty seems certain to involve robotic technology, although to what degree and in what capacity will depend on further high-quality studies assessing long-term outcomes, complications, survivorship and cost-benefit analyses.

Estimating aspect ratio of the distal femur and proximal tibia in the Emirati population from MRI scans of the knee: a preliminary experience

Size and shape of knee implants play an important role in the success of total knee arthroplasty. Several studies have identified anthropometric differences of the distal femur and proximal tibia between the genders and ethnicities. Ill-fitting prosthesis can cause overhang or under-fit resulting in persistence of pain, periprosthetic fracture and decreased range of motion. The purpose of this study was to estimate the aspect ratio of distal femur and proximal tibia in the Emirati population and determine whether gender differences exist within this group. Magnetic resonance imaging datasets of unilateral knees scans performed on adult Emirati patients at a tertiary care hospital were retrospectively examined. Knee parameters were obtained from 65 males and 46 females (n = 111). Females showed significantly smaller AP and ML dimensions of distal femur and lower aspect ratios compared to males (p < 0.001). Proximal tibial dimensions (AP and ML) of Emirati women are also significantly smaller compared to men. However, aspect ratio of proximal tibia did not show gender variation (p = 0.956) within the Emirati population. Emirati knees showed significant gender differences in bony dimensions and aspect ratio of the knee, and also have smaller aspect ratios when compared with most other population groups.

Patellar tendon elastic properties derived from in vivo loading and kinematics

Patellar complications frequently limit the success of total knee arthroplasty. In addition to the musculoskeletal forces themselves, patellar tendon elastic properties are essential for driving patellar loading. Elastic properties reported in the literature exhibit high variability and appear to differ according to the methodologies used. Specifically in total knee arthroplasty patients, only limited knowledge exists on in vivo elastic properties and their corresponding loads. For the first time, we report stiffness, Young’s modulus, and forces of the patellar tendon, derived from four patients with telemetric total knee arthroplasties using a combined imaging and measurement approach. To achieve this, synchronous in vivo telemetric assessment of tibio-femoral contact forces and fluoroscopic assessment of knee kinematics, along with full body motion capture and ground reaction forces, fed musculoskeletal multi-body models to quantify patellar tendon loading and elongation. Mechanical patellar tendon properties were calculated during a squat and a sit-stand-sit activity, with resulting tendon stiffness and Young’s modulus ranging from 511 to 1166 N/mm and 259 to 504 MPa, respectively. During these activities, the patellar tendon force reached peak values between 1.31 and 2.79 bodyweight, reaching levels of just ∼0.5 bodyweight below the tibio-femoral forces. The results of this study provide valuable input data for mechanical simulations of the patellar tendon and the whole resurfaced knee.

Not All Patients Need Supervised Physical Therapy After Primary Total Knee Arthroplasty: A Systematic Review and Meta-Analysis.

Although postoperative physical therapy (PT) has long been considered essential to successful total knee arthroplasty (TKA) recovery, recent literature has suggested that unsupervised home exercise regimens may offer similar benefits to formal supervised sessions. We aimed to compare objectively measured physical function and subjective patient-reported outcomes (PROs) between primary TKA patients who received formal supervised physical therapy sessions and those who received unsupervised home exercise regimens after discharge. Six electronic databases were queried to identify randomized controlled trials comparing supervised physical therapy to unsupervised home exercise regimens in primary TKA patients after discharge. Outcomes of interest included change from baseline in objective measures (knee flexion range of motion (ROM), lower extremity strength, and aerobic capacity) and PROs (physical function and quality of life scores). These outcomes were subdivided into short-term (<6 months from surgery; closest data point to three months is used if multiple measurements were made in this time period) and long-term (≥6 months from surgery; closest data point to 12 months is used if multiple measurements were made in this time period) assessments. A total of 1,884 cases performed in 11 studies were included in this review. There were no significant differences between cohorts with regardto short-term knee flexion ROM (p = 0.7), lower extremity strength (p = 0.6), or patient-reported quality of life (p = 0.5), as well as long-term knee flexion ROM (p = 0.7), patient-reported quality of life (p = 0.2), or patient-reported physical outcome scores (p = 0.3). A small difference in short-term patient-reported physical outcomes was observed in favor of the supervised cohort (standardized mean difference(SMD): 0.3 (95% confidence interval (CI): 0.01, 0.6); I2= 82%; p = 0.04). Formal supervised physical therapy regimens do not confer clinically significant benefits over unsupervised home exercise regimens following primary TKA. The routine use of supervised physical therapy after discharge may not be warranted. Further study is needed to determine the subset of patients that may benefit from supervised care.