Anesthesia for the Patient Undergoing Knee Procedures.

Anesthesia for patients undergoing knee procedures encompasses a large patient population with significant variation in patient age, comorbidities, and type of surgery. In addition, these procedures are performed in vastly different surgical environments, including large academic hospitals, private hospitals, and out-patient surgical centers. These variabilities require a thoughtful and individualized anesthetic approach tailored toward the medical and surgical needs of each patient. This article discusses anesthetic approaches to patients with acute, subacute, and chronic knee-related pathology requiring surgery. We will also review pertinent knee anatomy and innervation and discuss regional nerve blocks and their applications to knee-related surgical procedures.

Discharge Opioid Dose Indirectly Associated With Functional Outcomes 2 Weeks After Shoulder and Knee Arthroscopy in a US Military Sample.

INTRODUCTION: Postsurgical opioid utilization may be directly and indirectly associated with a range of patient-related and surgery-related factors, above and beyond pain intensity. However, most studies examine postsurgical opioid utilization without accounting for the multitude of co-occurring relationships among predictors. Therefore, this study aimed to identify factors associated with opioid utilization in the first 2 weeks after arthroscopic surgery and examine the relationship between discharge opioid prescription doses and acute postsurgical outcomes. METHODS: In this prospective longitudinal observational study, 110 participants undergoing shoulder or knee arthroscopies from August 2016 to August 2018 at Walter Reed National Military Medical Center completed self-report measures before and at 14 days postoperatively. The association between opioid utilization and both patient-level and surgery-related factors was modeled using structural equation model path analysis. RESULTS: Participants who were prescribed more opioids took more opioids, which was associated with worse physical function and sleep problems at day 14, as indicated by the significant indirect effects of discharge opioid dose on day 14 outcomes. Additional patient-level and surgery-related factors were also significantly related to opioid utilization dose and day 14 outcomes. Most participants had opioid medications leftover at day 14. CONCLUSION: Excess opioid prescribing was common, did not result in improved pain alleviation, and was associated with poorer physical function and sleep 14 days after surgery. As such, higher prescribed opioid doses could reduce subacute functioning after surgery, without benefit in reducing pain. Future patient-centered studies to tailor opioid postsurgical prescribing are needed.

Tratamiento de la contractura en flexión de rodilla en parálisis cerebral / Treatment for knee flexion contracture in cerebral palsy

La extensión completa de la rodilla es esencial para la marcha. Los pacientes con parálisis cerebral infantil con frecuencia pueden tener déficit de extensión de distinta magnitud, lo que compromete la marcha e incluso la bipedestación. El tratamiento de la contractura en flexión de rodilla parte por tratar la espasticidad de los músculos comprometidos y con fisioterapia. Cuando el flexo es estructurado, el tratamiento es quirúrgico mediante distintas técnicas, dependiendo de la magnitud de la contractura y de la edad del paciente. Las técnicas sobre partes blandas incluyen alargamientos funcionales de isquiotibiales y transferencias musculares. Cuando la contractura es capsular, es preferible realizar cirugía ósea, la cual extiende el fémur proximal, ya sea en forma progresiva, mediante fisiodesis anterior en pacientes pediátricos, o en forma aguda, mediante osteotomía extensora del fémur distal. Con frecuencia existe una patela alta, la cual hay que corregir en el mismo acto quirúrgico para mantener la eficiencia del aparato extensor

Full knee extension is essential for gait. Patients with cerebral palsy frequently have extension deficits of different magnitudes, which compromise walking and even standing up. The treatment of knee flexion contracture begins by addressing the spasticity of the involved muscles and includes physical therapy. For structured extension deficits, the treatment is surgical, using different techniques depending on the magnitude of the contracture and the patient's age. Soft tissue techniques include functional hamstring lengthening and muscle transfers. For capsular contracture, bone surgery is preferable and extends the proximal femur either progressively, through anterior physiodesis in pediatric patients, or acutely, by extensor distal femoral osteotomy. A high patella is common and requires correction during the same surgical procedure to maintain the efficiency of the extensor apparatus

Effects of Kinesio taping on lower limb biomechanical characteristics during the cutting maneuver in athletes after anterior cruciate ligament reconstruction.

PURPOSE: To determine the effects of Kinesio taping (KT) on the biomechanical characteristics of the lower limbs during the 90° cutting maneuver in anterior cruciate ligament (ACL) reconstruction (ACLR) athletes. METHOD: Eighteen ACLR athletes were recruited and subjected randomly to three taping conditions, KT, placebo taping (PT), and no taping (NT), followed by a 90° cutting test. A nine-camera infrared high-speed motion capture system (Vicon, T40, 200 Hz) was used to record the kinematic parameters of the lower limbs during the cutting maneuver, and a three-dimensional dynamometer (Kistler, 1000 Hz) was used to record the kinetic parameters of the lower limbs. A one-way repeated measures analysis of variance was conducted to compare the differences in the lower limb kinematic and kinetic characteristics of ACLR athletes subjected to these interventions. RESULTS: During the landing phase, the knee valgus angle reduced significantly with KT than with NT (95% confidence interval = -1.399 to -0.154; P = 0.025), whereas no significant difference was observed between PT and NT (95% confidence interval = -1.251 to 0.217; P = 0.236). No significant differences were observed in the other kinematic variables among the three taping conditions (P > 0.05). During the landing phase, no significant differences in the kinetic variables were observed among the three taping conditions (P > 0.05). CONCLUSIONS: Although KT does not improve the kinetic variables of athletes after ACLR during the 90° cutting maneuver, it reduces the knee valgus angle, which could reduce the risk of secondary ACL injury.

The characteristics and predictors of mortality in periprosthetic fractures around the knee.

Aims: Periprosthetic fractures (PPFs) around the knee are challenging injuries. This study aims to describe the characteristics of knee PPFs and the impact of patient demographics, fracture types, and management modalities on in-hospital mortality. Methods: Using a multicentre study design, independent of registry data, we included adult patients sustaining a PPF around a knee arthroplasty between 1 January 2010 and 31 December 2019. Univariate, then multivariable, logistic regression analyses were performed to study the impact of patient, fracture, and treatment on mortality. Results: Out of a total of 1,667 patients in the PPF study database, 420 patients were included. The in-hospital mortality rate was 6.4%. Multivariable analyses suggested that American Society of Anesthesiologists (ASA) grade, history of peripheral vascular disease (PVD), history of rheumatic disease, fracture around a loose implant, and cerebrovascular accident (CVA) during hospital stay were each independently associated with mortality. Each point increase in ASA grade independently correlated with a four-fold greater mortality risk (odds ratio (OR) 4.1 (95% confidence interval (CI) 1.19 to 14.06); p = 0.026). Patients with PVD have a nine-fold increase in mortality risk (OR 9.1 (95% CI 1.25 to 66.47); p = 0.030) and patients with rheumatic disease have a 6.8-fold increase in mortality risk (OR 6.8 (95% CI 1.32 to 34.68); p = 0.022). Patients with a fracture around a loose implant (Unified Classification System (UCS) B2) have a 20-fold increase in mortality, compared to UCS A1 (OR 20.9 (95% CI 1.61 to 271.38); p = 0.020). Mode of management was not a significant predictor of mortality. Patients managed with revision arthroplasty had a significantly longer length of stay (median 16 days; p = 0.029) and higher rates of return to theatre, compared to patients treated nonoperatively or with fixation. Conclusion: The mortality rate in PPFs around the knee is similar to that for native distal femur and neck of femur fragility fractures. Patients with certain modifiable risk factors should be optimized. A national PPF database and standardized management guidelines are currently required to understand these complex injuries and to improve patient outcomes.

High three-dimensional accuracy of component placement and lower limb alignment using a robotic arm-assisted system and gap-balancing instrument in total knee arthroplasty.

PURPOSE: It was hypothesized that robotic arm-assisted total knee arthroplasty (RA-TKA) using additionally a gap-balancing instrumentation will show high accuracy in executing the planning in femoral and tibial component placement throughout the range of knee motion (ROM) during TKA surgery. METHODS: Prospectively collected data were analysed for patients undergoing RA-TKA. A cruciate retaining cemented design was implanted using the MAKO® robotic system. Lower limb alignment at 0°, 30°, 45°, 60° and 90° of flexion was recorded at the beginning of surgery and finally after implantation of the components. A ligament tensioner was inserted after tibial precut to measure the extension and flexion gap, and final component placement was planned based on 3D CT images. Femoral and tibial component placement was measured in all three planes. RESULTS: A total of 104 patients were included (mean age 69.4 ± 9 years; 44 male, 60 female). The difference in component placement after planning and final implantation showed less valgus of 0.7° ± 1.4° (p < 0.001), less external rotation of 0.6° ± 1.9° (p = 0.001) and less flexion of 0.9° ± 1.8° (p < 0.001) for the femoral component. The tibial component was placed in more varus of 0.2° ± 0.9° (p = 0.056) and more posterior slope of 0.5° ± 0.9° (p < 0.001). The lower limb alignment in extension was 4.4° ± 5.2° of varus of the native knee and changed to 1.2° ± 1.9° of varus after TKA (p < 0.01). CONCLUSION: Robotic-assisted TKA helps to achieve the target of alignment and component placement very close to the planning. It allows optimal component placement of off-the-shelf implants respecting patient's specific anatomy. LEVEL OF EVIDENCE: Level II.

Global knee function rating more strongly influences adolescent athletes that sustain a sports-related surgical ACL re-injury or contralateral ACL injury.

PURPOSE: This study evaluated differences between adolescent athletes who sustained a surgical anterior cruciate ligament (ACL) re-injury, or contralateral ACL injury following return to sports bridge programme participation (Group 1) compared to those that did not (Group 2). METHODS: At 19.9 ± 7 years of age, 198 athletes participated in this study. Groups were compared for time postsurgery, preprogramme and postprogramme Knee Outcome Survey Sports Activity Scale (KOS-SAS) and global rating of knee function (GRKF) during sports activities, postprogramme lower extremity physical function test performance and perceived sports performance compared to preinjury level. RESULTS: By 6.0 ± 3.2 years postsurgery, 11 (5.6%) sustained another ACL injury. Group 1 was younger (17.3 ± 1.7 years vs. 20.1 ± 6.8 years, p < 0.001). Postprogramme re-evaluation revealed that Group 1 had a greater GRKF compared to their programme initiation GRKF than Group 2 (32.6 ± 38 vs. 20.0 ± 23, p = 0.04). Group 1 also had a greater mean preprogramme to postprogramme GRKF change than Group 2 (51.3 ± 31 vs. 35.5 ± 21, p = 0.02) (effect size = 0.73). More Group 1 subjects also had a GRKF difference that exceeded the overall mean than Group 2 (p = 0.04). Group 1 had moderately strong relationships between preprogramme and postprogramme GRKF score change and the postprogramme GRKF score (r = 0.65, p = 0.04) and between preprogramme and postprogramme KOS-SAS score change and postprogramme GRKF score (r = 0.60, p = 0.04). CONCLUSION: Global rating scores had a stronger influence among adolescent athletes that sustained either surgical ACL re-injury or contralateral ACL injury. Since group physical function and neuromuscular control factors were similar, clinicians need to increase their awareness and understanding of other factors that may influence surgical ACL re-injury or contralateral ACL injury risk. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Femoral anterior condyle height decreases as the distal anteroposterior size increases in total knee arthroplasty: A comparative study.

PURPOSE: The anterior flange height of the current femoral component increases with an increasing distal femoral anteroposterior dimension. During total knee arthroplasty (TKA), we have observed that a large femur may have a thinner anterior condyle, whereas a small femur may have a thicker anterior condyle. The first purpose of this study was to examine whether the femoral anterior condyle height decreases as the distal femoral anteroposterior size increases and whether gender differences exist in anterior condyle height. METHODS: A total of 1218 knees undergoing TKA intraoperative and computed tomography scans from 303 healthy knees were used to measure the anterior lateral condylar height (ALCH), anterior medial condylar height (AMCH), and the lateral anteroposterior (LAP) and medial anteroposterior (MAP) dimensions of distal femurs. The LAP and MAP measurements were used for adjustments to determine whether gender differences exist in anterior condyle heights. Linear regression analysis was performed to determine correlations between ALCH and LAP or between AMCH and MAP. RESULTS: There were significant differences between males and females in ALCH in both the CT and TKA groups and AMCH in the CT group (all P<0.01). After adjusting for LAP and MAP, there were significant gender differences in the lateral and medial condylar heights in both groups (P<0.01). There were significant negative correlations between ALCH and LAP values and between AMCH and MAP values in both CT and TKA measurements, with the LAP and MAP values increasing as ALCH and AMCH decreased. CONCLUSIONS: The results demonstrate that femoral anterior condylar height decreased with increasing anteroposterior dimension in both the medial and lateral condyle. In addition, this study also showed that anterior condylar heights are highly variable, with gender differences. The data may provide an important reference for designing femoral anterior flange thickness to precisely match the natural anterior condylar anatomy.

Therapeutic effect of knee extension exercise with single-joint hybrid assistive limb following total knee arthroplasty: a prospective, randomized controlled trial.

The single-joint hybrid assistive limb (HAL-SJ), an exoskeletal robotic suit, offers functional improvement. In this prospective randomized controlled trial, we investigated the therapeutic effects of knee extension exercises using the HAL-SJ after total knee arthroplasty (TKA). Seventy-six patients with knee osteoarthritis were randomly assigned to HAL-SJ or conventional physical therapy (CPT) groups. The HAL-SJ group underwent exercise using the HAL-SJ for 10 days postoperatively, in addition to CPT; the CPT group underwent only CPT. Pain intensity and active and passive knee extension angles were evaluated preoperatively and on postoperative days 1-10 and weeks 2 and 4. Performance tests and Knee Injury and Osteoarthritis Outcome Scores (KOOS) were evaluated preoperatively and at postoperative weeks 2 and 4. Statistical analysis showed that the HAL-SJ group significantly improved active and passive knee extension angles compared with the CPT group. The HAL-SJ group showed immediate improvement in active knee extension angle through day 5. There were no significant differences in results between the performance tests and KOOS. Knee extension exercises with the HAL-SJ improved knee pain and the angle of extension in the acute phase after TKA.

Tibial morphology of symptomatic osteoarthritic knees varies according to location: a retrospective observational study in Japanese patients.

This study analyzed 31 patients with symptomatic osteoarthritic knees scheduled to undergo knee arthroplasty or high tibial osteotomy and demonstrated shape variations in their proximal tibia using an average three-dimensional (3D) bone model. Preoperative computed tomography of the affected knees was reconstructed as 3D bone models using a triangle mesh of surface layers. The initial case was defined as the template, and the other models were reconstructed into homologous models with the same number of mesh vertices as that in the template. The corresponding mesh vertices of the other models were averaged to evaluate the spatial position on the particular mesh vertex of the template. This was applied to all the mesh vertices of the template to generate the average 3D model. To quantify the variation in surface geometry, average minimum distance from the average bone model to 31 models was recorded. The medial proximal tibial cortex (1.63 mm) revealed lesser variation compared to the tibial tuberosity (2.50 mm) and lateral cortex (2.38 mm), (p = 0.004 and p = 0.020, respectively). The medial tibial plateau (1.46 mm) revealed larger variation compared to the lateral tibial plateau (1.16 mm) (p = 0.044). Understanding 3D geometry could help in development of implants for arthroplasty and knee osteotomy.

Knee biomechanics variability before and after total knee arthroplasty: an equality of variance prospective study.

This study evaluated gait variability in patients before and after total knee arthroplasty (TKA) using the equality of variance method to determine where variability differences occur in the movement cycle. Twenty-eight patients underwent TKA with cruciate-sacrificed implants. Patients underwent motion analysis which measured knee biomechanics as they walked overground at their preferred pace before and 12 months after TKA. Equality of variance results were compared with 14 healthy controls of similar age. Before surgery, patients had reduced knee extension moment variability throughout the early stance phase (4-21% gait cycle, p < 0.05) compared to controls. Knee power variability was lower preoperatively compared to controls for most of the stance phase (0-13% and 17-60% gait cycle, p < 0.05). Sagittal knee moment and power variability further decreased following TKA. Knee extension moment variability was lower postoperatively throughout stance phase compared to preoperatively (4-22% and 36-60% gait cycle, p < 0.05) and compared to controls (4-30% and 45-60% gait cycle, p < 0.05). Knee power variability remained lower following TKA throughout stance phase compared to preoperatively (10-24% and 36-58% gait cycle, p < 0.05) and controls (3-60% gait cycle, p < 0.05). TKA patients may be less stable, and this may be in part due to an unresolved adaptation developed while awaiting TKA surgery and the cruciate sacrificing design of the implants utilized in this study.

Single- or two-stage revision after failed ACL reconstruction: No differences in re-revision rates and clinical outcomes.

PURPOSE: The surgeons' choice of a single-stage or a two-stage procedure in revision anterior cruciate ligament reconstruction (ACLr) is based on the possibility of reuse of the tibia and femoral bone tunnels after primary ACLr. The purpose of this study was to compare failure rates and clinical outcomes following single-stage and two-stage ACL revisions in a cohort of patients from The Danish Knee Ligament Reconstruction Registry. METHODS: Patients identified from 2005 to 2022 with ACL revision and met the following criteria: minimum 2-year follow-up, isolated ACL revision and registered single- or two-stage ACL revision. The primary outcome was ACL re-revision rate. Secondary outcomes were arthrometer sagittal knee laxity (side-to-side difference) and pivot shift (rotational stability difference) evaluated at 1-year follow up. RESULTS: One thousand five hundred seventy-four ACL revisions were included in the study (1331 = single-stage and 243 = two stage). Baseline characteristics showed no difference in relation to age, gender, knee laxity, pivot shift, meniscus injury, cartilage damage or injury mechanism between the two groups. Significant differences were found in relation to the type of graft. No statistical difference in 2-years revision rates between single-stage group 2.79 (95% CI 2.03-3.84) and two-stage group 2.93 (95% CI 1.41-6.05) was found. No significant difference was seen in knee laxity and pivot shift between stage-groups at 1-year follow up. Both groups demonstrated significant improvements in knee stability from baseline to 1-year follow-up. CONCLUSION: The present study found that ACL revision outcomes were similar in terms of rerevision rates and knee laxity for patients managed with a single- or a two-stage surgical strategy. LEVEL OF EVIDENCE: Level III.

A randomised crossover trial of five cryocompression devices' ability to reduce skin temperature of the knee.

BACKGROUND: The application of cold and pressure to the knee is a common part of post-operative rehabilitation. Skin temperature should be reduced to within 10-15 °C to optimise the therapeutic benefits of cryocompression. The purpose of this study was to investigate the ability of five different cryocompression devices to reduce skin temperature to within this therapeutic range. MATERIALS AND METHODS: 32 healthy adult participants (mean (SD): age 26.3 (7.9) years; BMI 24.8 (2.7) kg/m2; 20 males) were recruited for this randomised crossover study. Skin temperature was measured 20 mm distal to the patella using a k-type thermocouple every five minutes during a 30-minute treatment with one of five different cryocompression devices (Physiolab S1, GameReady, Cryo/Cuff, VPulse, and a Gel Wrap). Changes in skin temperature over time were compared to baseline within and between conditions. A subjective rating of comfort was also recorded for each device. RESULTS: The Physiolab S1 and GameReady devices caused significantly lower skin temperatures compared to the VPulse, Gel Wrap, and Cryo/Cuff after 30 minutes (p<0.05). 87-96% reported a positive comfort rating for the Physiolab S1, VPulse, Cryo/Cuff and Gel Wrap, whereas 53% of participants reported a positive comfort rating for the GameReady. CONCLUSIONS: Only the Physiolab S1 and GameReady devices reduced skin temperature of the knee to within the target range of 10-15 °C. The Physiolab S1 was reportedly more comfortable than the GameReady. Clinicians should be aware of the performance differences of different cryocompression devices to understand which is most likely to provide an effective dose of cold therapy to a joint.

Editorial Commentary: A Gap-Based Subclassification of Ramp Lesions Has the Potential to Enhance Treatment Precision and Patient Outcomes in Anterior Cruciate Ligament-Deficient Knees Subtitle: Customizing Solutions for Anterior Cruciate Ligament-Deficient Knees.

Our evolving understanding of ramp lesions has significantly affected the field of anterior cruciate ligament injury and meniscal repair. Although these lesions have been linked consistently to increased anterior and rotational instability in anterior cruciate ligament-deficient knees, there remains a contentious debate regarding their optimal treatment. The current literature is divided, as some advocate for surgical repair of only arthroscopically unstable lesions. Others point to a substantial risk of complications, noting a 28.6% incidence in untreated stable lesions, and thus advocate for surgical repair of all lesions. Through the use of magnetic resonance imaging scans of flexed knees, a novel subclassification of ramp lesions based on gap distance at the tear site shows a correlation with posterior capsular displacement, anterior laxity, lesion size, and joint effusion. This nuanced classification offers new insights and promises to refine treatment decisions, potentially minimizing unnecessary surgeries and improving patient outcomes.

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

BACKGROUND: One 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. METHODS: In 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. RESULTS: The 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). CONCLUSION: The design change, which reduced the posterior lip of the PE insert, contributed to improved rotational arc in 120° and 130° deep flexion ranges.

Limb length change after total knee arthroplasty for valgus deformity does not affect the clinical score and is not affected by fixed flexion deformity.

BACKGROUND: The limb length change (LLC) after total knee arthroplasty (TKA) is especially significant in valgus deformity. The higher LLC could cause higher incidences of lower limb length discrepancy (LLD) and low clinical score. However, studies about LLC after TKA for valgus deformity are limited, and there are none on the relationship between LLC and fixed flexion deformity (FFD) in valgus deformity. HYPOTHESIS: (1) The amount of LLC would affect the postoperative LLD, (2) the improvement of fixed flexion deformity (FFD) would affect the amount of LLC, (3) The amount of LLC would affect the improvement in the clinical score after TKA for valgus deformity. PATIENTS AND METHODS: Fifty knees of 50 patients who underwent primary unilateral TKA for valgus-type osteoarthritis between January 2000 and October 2021 were included. A radiological and clinical assessment were performed the day before the operation and at 12 months post-operatively. Full-length standing anteroposterior radiographs were used to measure HKA and LLC. FFD and Hospital for Special Surgery (HSS) score were measured in the outpatient department. RESULTS: The incidence of lengthening was 92.0% and the mean LLC was 18.85mm (SD, 19.60mm). Postoperative LLD over 10mm occurred in 26% and the mean of postoperative LLD was 4.21mm (SD, 7.96mm). The LLC was correlated with postoperative LLD (rs=0.357, p=0.011) and the HKA change (rs=0.375, p=0.007), but not with the FFD improvement (rs=0.164, p=0.255) and HSS improvement (rs=0.076, p=0.613) or postoperative HSS (rs=0.094, p=0.528). CONCLUSION: LLC was affected by HKA improvement but not by FFD improvement after TKA for patients with valgus deformity. Additionally, LLC did not affect the clinical score. LEVEL OF EVIDENCE: III; retrospective cohort study.

Joint line position change in primary total knee arthroplasty: a radiographic analysis comparing conventional and robotic techniques.

PURPOSE: Joint line (JL) position change in total knee arthroplasty (TKA) may alter knee biomechanics and impact function. The purpose of this study was to compare the change in JL position between robotic-assisted TKA (RA-TKA) and conventional TKA (C-TKA). METHODS: A retrospective, radiographic analysis was conducted of patients who underwent RA-TKA and C-TKA to compare JL position change. JL position was measured in consecutive RA-TKAs and C-TKAs performed by four fellowship-trained arthroplasty surgeons. Statistical analysis was done utilizing t-tests and Mann Whitney U tests, with statistical significance being defined as a p value < 0.05. RESULTS: Six hundred total RA-TKAs and 400 total C-TKAs were included in the analysis. There were no significant differences in patient baseline characteristics such as body mass index, range of motion, and tibiofemoral coronal alignment. RA-TKAs were associated with an average of 0.04 (2.2) mm JL position change, and C-TKAs were associated with an average 0.5 (3.2) mm JL position change (p = 0.030). There were inter-surgeon differences when comparing the change in JL position for RA-TKAs and C-TKAs between the four participating surgeons. CONCLUSION: RA-TKA leads to better preservation of the JL position than C-TKA, and this seems to be dependent on the arthroplasty surgeon's preferences and techniques during TKA. Whether this statistically significant difference is clinically relevant needs to be further investigated.

No clinical advantage with customized individually made implants over conventional off-the-shelf implants in total knee arthroplasty: a systematic review and meta-analysis.

INTRODUCTION: Total knee arthroplasty (TKA) can be performed with either conventional off-the-shelf (OTS) or customized individually-made (CIM) implants. The evidence for CIM implants is limited and variable, and the aim of this review was to compare clinical and radiological outcomes between CIM and OTS implants. METHODS: A systematic review and meta-analysis were conducted in accordance with PRISMA guidelines. Studies reporting on clinical, radiological, or alignment outcomes for CIM and OTS implants were selected. The studies were appraised using the Methodical index for non-randomized studies tool. RESULTS: Twenty-three studies fulfilled the inclusion criteria. The studies comprised 2856 CIM and 1877 OTS TKAs. Revision rate was higher with CIM (5.9%) compared to OTS (3.7%) implants [OR 1.23(95% CI 0.69-2.18)]. Manipulation under anesthesia (MUA) was higher in CIM (2.2%) compared to OTS (1.1%) group [OR 2.95(95% CI 0.95-9.13)] and complications rate was higher in CIM (5%) vs. OTS (4.5%) [OR 1.45(95% CI 0.53-3.96)] but neither reached statistical significance. Length of stay was significantly shorter in CIM group 2.9 days vs. 3.5 days [MD - 0.51(95% CI - 0.82 to - 0.20)]. Knee Society Score showed no difference between CIM and OTS groups for Knee 90.5 vs. 90.6 [MD - 0.27(95% CI - 4.27 to 3.73)] and Function 86.1 vs. 83.1 [MD 1.51(95% CI - 3.69 to 6.70)]. CONCLUSION: CIM implants in TKA have theoretical benefits over OTS prostheses. However, in this present review, CIM implants were associated with higher revisions, MUA, and overall complication rates. There was no difference in outcome score and CIM implants did not improve overall target alignment; however, more CIM TKAs were found to be in the HKA target zone compared to OTS TKAs. The findings of this review do not support the general utilization of CIM over OTS implants in TKA.

Lateral versus medial approach for total knee arthroplasty for valgus knee deformity shows comparable functional outcomes, hip-knee-ankle angle values, and complication rates: a meta-analysis of comparative studies.

INTRODUCTION: The aim of this meta-analysis of comparative studies was to update the current evidence on functional and radiographic outcomes and complications between medial and lateral approaches for total knee arthroplasty (TKA) for valgus knee deformity. MATERIALS AND METHODS: The PubMed, MEDLINE, Scopus, and the Cochrane Central databases were used to search keywords and a total of ten studies were included. The methodological quality of the included studies was assessed. Data extracted for quantitative analysis included the Knee Society score (KSS), range of motion (ROM), surgical time, hip-knee-ankle angle (HKA), and number and types of complications. Random- and fixed-effect models were used for the meta-analysis of pooled mean differences (MDs) and odds ratios (ORs). The Mantel-Haenszel method was adopted. RESULTS: A total of 1008 patients were identified, of whom 689 and 319 underwent TKA for valgus knee deformity with lateral and medial approach, respectively. The mean age was 70 ± 9.5 and 67.3 ± 9.6 years for the lateral and medial approaches, respectively. The mean follow-up was 37.8 ± 21.9 and 45.9 ± 26.7 months for the lateral and medial approach groups, respectively. Significantly higher functional outcomes were found for the medial approach, as measured by the postoperative KSS (MD = 1.8, 95% CI [0.48, 3.12], P = 0.007) and flexion ROM (MD = 3.12, 95% CI [0.45, 5.79], P = 0.02). However, both of these differences were lower than the minimal clinically important difference. Comparable surgical time and postoperative HKA angle values (MD = 0.22, 95% CI [- 0.30, 0.75], P = 0.40) between the two surgical approaches were found. The incidence of periprosthetic joint infections, fractures, transient peroneal nerve injuries, and deep vein thrombosis was comparable. CONCLUSION: This meta-analysis of comparative studies showed that when lateral and medial approaches are used for total knee arthroplasty for valgus knee deformity, comparable functional outcomes in terms of the KSS and ROM, surgical time, and postoperative hip-knee-ankle angle values can be expected. Similar rates of periprosthetic joint infection, fracture, and peroneal nerve injury were also found. LEVEL OF EVIDENCE: I. PROSPERO REGISTRATION NUMBER ID: CRD42023392807.