Femoral Notch Research Articles

Appropriate sagittal positioning of femoral components in total knee arthroplasty to prevent fracture and loosening.

This study aimed to investigate the optimal sagittal positioning of the uncemented femoral component in total knee arthroplasty to minimize the risk of aseptic loosening and periprosthetic fracture. Ten different sagittal placements of the femoral component, ranging from -5 mm (causing anterior notch) to +4 mm (causing anterior gap), were analyzed using finite element analysis. Both gait and squat loading conditions were simulated, and Von Mises stress and interface micromotion were evaluated to assess fracture and loosening risk. During gait, varied sagittal positioning did not lead to excessive Von Mises stress or micromotion. However, under squat conditions, posterior positioning (-4 and -5 mm) resulted in stress exceeding 150 MPa at the femoral notch, indicating potential fracture risk. Conversely, +1 mm and 0 mm sagittal positions demonstrated minimal interface micromotion. Slightly anterior sagittal positioning (+1 mm) or neutral positioning (0 mm) effectively reduced stress concentration at the femoral notch and minimized interface micromotion. Thus, these positions are deemed suitable to decrease the risk of aseptic loosening and periprosthetic femoral fracture.

Stem to prevent periprosthetic fracture after notching in total knee arthroplasty.

Improper osteotomy during total knee arthroplasty (TKA) can lead to anterior femoral notching, which increases the risk of periprosthetic fractures due to stress concentration. One potential solution is the addition of an intramedullary stem to the femoral component. However, the optimal stem length remains unclear. In this study, we aimed to determine the optimal stem length using finite element models. Finite element models of femurs were developed with unstemmed prostheses and prostheses with stem lengths of 50, 75, and 100 mm. Under squat loading conditions, the von Mises stress at the notch and stress distribution on four transversal sections of the femur were analyzed. Additionally, micromotion of the prosthesis-bone interface was evaluated to assess initial stability. The unstemmed prosthesis exhibited a von Mises stress of 191.8 MPa at the notch, which decreased to 43.1, 8.8, and 23.5 MPa for stem lengths of 50, 75, and 100 mm, respectively. The stress reduction on four selected femoral transversal sections compared with the unstemmed prosthesis was 40.0%, 84.4%, and 67.1% for stem lengths of 50, 75, and 100 mm, respectively. Micromotion analysis showed a maximum of 118.8 μm for the unstemmed prosthesis, which decreased significantly with the application of stems, particularly at the anterior flange. Intramedullary stems effectively reduced stress concentration at the femoral notch. The 50-mm stem length provided the optimal combination of reduced notch stress, minimized stress-shielding effect, and decreased micromotion at the anterior flange.

Total knee arthroplasty and periprosthetic distal femoral fracture: looking beyond the osteoporosis to previous osteoporotic fracture.

Osteoporosis is a risk factor for fractures, including those of the hip, vertebrae, and distal radius; however, the association between osteoporosis and periprosthetic fractures after total knee arthroplasty (TKA) has not been much investigated. Therefore, we aimed to investigate the association of the presence of systemic osteoporosis with periprosthetic fractures after TKA. This study included 34 patients with periprosthetic fractures following primary TKA and 106 controls matched for age and sex. Bone mineral density was evaluated at the femoral neck, total hip, and lumbar spine using dual X-ray absorptiometry. Medical records were reviewed for age; sex; body mass index; smoking; rheumatoid arthritis, endocrine diseases, and cardiovascular diseases; history of glucocorticoid use; medication for osteoporosis; and history of previous osteoporotic fracture. In addition, anterior femoral notching after TKA was evaluated. Univariable and multivariable logistic regression analysis were used to determine factors associated with periprosthetic fracture. The prevalence of osteoporosis in the fracture group was higher than that in the control group (61.8% vs. 40.6%, p=0.045). The rate of medication for osteoporosis was significantly low in the fracture group (47.6 % vs 76.7%, p=0.026). History of previous osteoporotic fracture (odds ratio [OR], 9.1; p=0.015) and osteoporosis (OR, 3.6; p=0.013) were significant risk factors for periprosthetic fractures after TKA. Medication for osteoporosis could decrease the risk of periprosthetic fracture (OR 0.3; p=0.020). Osteoporosis is a major risk factor for periprosthetic distal femoral fractures after TKA. Therefore, careful assessment and proper treatment of osteoporosis need and the importance of taking osteoporotic medication needs to be recognized to the patients following primary TKA, especially in patients with a history of osteoporotic fracture. Prognostic study, level III.

Three-dimensional bone morphology is a risk factor for medial postmeniscectomy syndrome: A retrospective cohort study.

The study aims to identify differences in tibiofemoral joint morphology between responders (R group, no pain) to arthroscopic partial medial meniscectomy (APMM) versus medial postmeniscectomy syndrome patients (MPMS group, recurrent pain at 2 years postmeniscectomy) in a clinically neutrally aligned patient population. The second aim was to build a morphology-based predictive algorithm for response to treatment (RTT) in APMM. Two patient groups were identified from a large multicentre database of meniscectomy patients at 2 years of follow-up: the R group included 120 patients with a KOOS pain score > 75, and the MPMS group included 120 patients with a KOOS pain score ≤ 75. Statistical shape models (SSMs) of distal femur, proximal tibia and tibiofemoral joint were used to compare knee morphology. Finally, a predictive model was developed to predict RTT, with the SSM-derived morphologic variables as predictors. No differences were found between the R and MPMS groups for patient age, sex, height, weight or cartilage status. Knees in the MPMS group were significantly smaller, had a wider femoral notch and a smaller medial femoral condyle. A morphology-based predictive model was able to predict MPMS at 2 years follow-up with a sensitivity of 74.9% (95% confidence interval [CI]: 74.4%-75.4%) and a specificity of 81.0% (95% CI: 80.6%-81.5%). A smaller tibiofemoral joint, a wider intercondylar notch and smaller medial femoral condyle were observed shape variations related to medial postmeniscectomy syndrome. These promising results are a first step towards a knee morphology-based clinical decision support tool for meniscus treatment. Case-control study. Level IIIb.

Arthroscopic treatment of femoral trochlear notch fracture caused by intra-articular dislocation of the patella

This case report presents a traumatic intra-articular patellar dislocation – associated intercondylar fracture of the distal femur – and the consequent arthroscope assisted reduction and percutaneous screw fixation. To the best of our knowledge, this is the first case in which the arthroscope assisted operative reduction and percutaneous screw fixation of the fracture fragment has been demonstrated. Our patient was a 55-year-old female who was treated by the aforementioned method which concluded with excellent results.

The presence of a deep lateral femoral notch sign in ACL-injured patients is associated with a 2.7° steeper posterior tibial slope and a 19% higher frequency of lateral meniscal injuries.

The purpose of this study was to study the relationship between the presence of a deep lateral femoral notch sign (DLFNS) in anterior cruciate ligament (ACL)-injured patients and a higher posterior lateral tibial slope (LPTS), a reduced meniscal bone angle (MBA), a higher LPTS/MBA ratio and a higher incidence of concomitant injuries in primary ACL tears. A retrospective case-control study was performed in patients submitted to primary ACL reconstruction with an available preoperative magnetic resonance imaging (MRI) scan. Patients with ACL tears and a femoral impactation with a depth ≥2 mm were assorted to the DLFNS groupand patients with ACL tear and without a DLFNS to the control group. LPTS and MBA were measured in MRI. The presence of concomitant injuries (meniscal, posterior cruciate ligament, medial collateral ligament, lateral collateral ligament and bone injuries) was assessed in MRI. Quantitative data are presented in the median ± interquartile range (IQR). There were 206 patients included in the study, with 46 patients assorted to the DLFNS group and 160 patients to the control group. In the DLFNS group, the median LPTS was 6.7° (IQR: 4.0-8.2) versus 4.0° in the control group (IQR: 2.2-6.5) (p = 0.003). The LPTS/MBA ratio was significantly higher in the DLFNS group, with a median of 0.32 (IQR: 0.19-0.44), in comparison to the control group, with a median of 0.19 (IQR: 0.11-0.31) (p < 0.001). The multivariable logistic regression analysis showed that the LPTS is an independent risk factor to having a DLFNS (odds ratio [OR] = 1.161; 95% confidence interval [CI]: 1.042-1.293, p = 0.007). There was a higher incidence of concomitant lateral meniscal injuries in the DLFNS group (67% vs. 48%, p = 0.017). In patients with ACL tears, the presence of a DLFNS is associated with a steeper lateral posterior tibial slope, as well as a higher incidence of concomitant lateral meniscal injuries. Level III.

Radiographic analysis in Thoroughbreds reveals morphological changes in healthy maturing stifle joints and possible association between subchondral lesions and femoral condyle width.

Assess femorotibial features in foals with and without medial femoral condyle (MFC) subchondral radiolucencies (SR+ and SR-). 3 independent, sequential radiographic studies were performed. Study 1 retrospectively measured femorotibial morphological parameters in repository radiographs (SR- and SR+). Study 2 qualitatively compared drawings of intercondylar notch shape in postmortem radiographs (SR-). Study 3 prospectively measured femorotibial parameters in 1-month-old foals (SR-). In studies 1 and 3, 13 morphologic parameters were measured. Limb directional asymmetry was assessed in 2 age groups (< 7 or ≥ 7 months). Study 1 (SR- group; n = 183 radiographs) showed increased femoral measurements with maturation, except the distal femoral intercondylar notch width (FINwal), which decreased. In contrast, in SR+ stifles (53 radiographs), 3 femoral parameters (MFC width [MFCwpf], MFC height, or FINwal) showed no changes. Tibial plateau width alone increased with maturation in both groups. Interobserver reliability was good to excellent. Study 2 (n = 53 radiographs) confirmed a distal FINw decrease in SR- foals. In study 1, left SR- stifles in greater than or equal to 7-month-old fillies had significantly larger femoral bicondylar width and FINw, while right SR+ stifles in fillies greater than or equal to 7 months had a significantly larger MFCw. In study 3 of 1-month-old foals (n = 94 SR- radiographs), the MFCw, femoral condyle bicondylar width, and lateral femoral condyle height were all greater on the left, whereas the intercondylar intereminence space width was larger on the right. In SR+ stifles, the distal femur exhibited divergent maturation, indicating a wider MFC in the right stifle in older foals. As SR lesions are more common on the right, this suggests a potential association with MFC morphology.

Effect of anterior femoral cortical notch grade on postoperative function and complications during TKA surgery: A multicenter, retrospective study.

To explore the effect of AFN on knee function and complications in patients after TKA. We evaluated 150 patients undergoing unilateral TKA, specifically including 102 patients with varying degrees of AFN after selection. They were divided into four groups based on AFN grade. About 48 patients did not produce AFN, 63 patients were grade I, 29 patients were grade II, and 10 patients were grade III. All patients were followed up for 24 months, and knee function, pain, complications, and other indicators were compared between the four groups. Correlation analysis and regression analysis were used to study the relationship between AFN and other indicators. Two cases of periprosthetic fractures (PPF) occurred in our study, with an incidence of 1.35%, which did not show a significant association with AFN. The changes in knee social score (ΔKSS), Western Ontario and McMaster Universities Osteoarthritis Index (ΔWOMAC), and postoperative anterior knee pain visual analog scale (VAS) score were higher in patients with AFN than in those without. Particularly, grades II and III AFN demonstrated superior efficacy. Pearson's correlation analysis showed that AFN grade is positively correlated with both ΔKSS and ΔWOMAC (r = 0.44, P < 0.001), and AFN grade had a negative correlation with the anterior knee pain VAS (r = -0.250, P < 0.05). In linear regression analysis, AFN grade was positively correlated with both ΔKSS (β = 5.974, 95% CI: 3.968-7.981, P < 0.001) and ΔWOMAC (β = 6.356, 95% CI: 4.223-8.490, P < 0.001). Besides that, there was a negative correlation between AFN grade and anterior knee pain (β = 5.974, 95% CI: 3.968-7.981, P < 0.05). Patients with grade II and III AFN who underwent TKA exhibited better knee function and lower levels of anterior knee pain post-surgery.

Impact of Selective Posterior Cruciate Ligament Fiber Release on Femoral Rollback in Cruciate-Retaining Total Knee Arthroplasty: A Computational Study

BackgroundPartial or total release of the posterior cruciate ligament (PCL) is often performed intraoperatively in cruciate-retaining total knee arthroplasty (CR-TKA) to alleviate excessive femoral rollback. However, the effect of the release of selected fibers of the PCL on femoral rollback in CR-TKA is not well understood. Therefore, we used a computational model to quantify the effect of selective PCL fiber releases on femoral rollback in CR-TKA. MethodsComputational models of 9 cadaveric knees (age: 63 years, range 47 to 79) were virtually implanted with a CR-TKA. Passive flexion was simulated with the PCL retained and after serially releasing each individual fiber of the PCL, starting with the one located most anteriorly and laterally on the femoral notch and finishing with the one located most posteriorly on the medial femoral condyle. The experiment was repeated after releasing only the central PCL fiber. The femoral rollback of each condyle was defined as the anterior-posterior distance between tibiofemoral contact points at 0° and 90° of flexion. ResultsRelease of the central PCL fiber in combination with the anterolateral (AL) fibers, reduced femoral rollback a median of 1.5 [0.8, 2.1] mm (P = .01) medially and by 2.0 [1.2, 2.5] mm (P = .04) laterally. Releasing the central fiber alone reduced the rollback by 0.7 [0.4, 1.1] mm (P < .01) medially and by 1.0 [0.5, 1.1] mm (P < .01) laterally, accounting for 47 and 50% of the reduction when released in combination with the AL fibers. ConclusionsReleasing the central fibers of the PCL had the largest impact on reducing femoral rollback, either alone or in combination with the release of the entire AL bundle. Thus, our findings provide clinical guidance regarding the regions of the PCL that surgeons should target to reduce femoral rollback in CR-TKA.

Bone Density Distribution Pattern in the Lateral Wall of the Femoral Intercondylar Notch: Implications for the Direct Insertion of the Femoral ACL Attachment

Background: The ideal position of the femoral bone tunnel in the anterior cruciate ligament (ACL) is controversial. The functional importance of the ACL fiber varies depending on where it is attached to the femur. Functionally important fibers can cause high mechanical stress on the bone, and the Wolff law predicts that bone mineral density will increase at high mechanical stress sites. Purpose/Hypothesis: The purpose of this study was to use computed tomography imaging to determine the distribution pattern of bone density in the lateral intercondylar wall. It was hypothesized that the high-density area (HDA) of the lateral intercondylar wall would reflect the functional insertion of the ACL as reported in previous anatomic studies. Study Design: Descriptive epidemiology study. Methods: Data from 39 knees without ACL injuries were retrospectively collected. The HDA of the lateral intercondylar wall was defined as the region containing the top 10% of the radiodensity values. The shape of the HDA was approximated as an ellipse, and the quadrant method was used to determine the center of the ellipse. The association between the ratio of the minor axis to the major axis of the ellipse and background characteristics was investigated. Results: According to the quadrant method, the center of the HDA ellipse was 33.6% in the deep-shallow direction and 23.4% in the high-low direction. The center of the ellipse was comparable to the anatomic center of the ACL footprint, as previously reported. The ratio of the minor axis to the major axis of the ellipse was 0.58 (95% CI, 0.54-0.62). There was a significant negative correlation between the ratio of the minor axis to the major axis of the HDA ellipse and the posterior tibial slope ( r = −0.38, P = .02). Conclusion: The center of the HDA ellipse was found to be similar to the anatomic center of the ACL footprint. Considering the mechanical stress responses in bone, the HDA of the lateral intercondylar wall has the potential to represent the ACL insertion, especially functional insertion.

Tibial spine volume is smaller in ACL-injured athletes compared to healthy athletes.

The aim of this study was to investigate whether the whole tibial spine volume and femoral intercondylar notch volume are risk factors for anterior cruciate ligament (ACL) injury. The hypothesis was that the whole tibial spine volume and femoral notch volume would be smaller in athletes who sustained ACL injury than in athletes with no history of ACL injury. Computed tomography scans of both knees were acquired and three-dimensionalbone models were created using Mimics to measure whole tibial spine volume and femoral notch volume. Tibial spine volume, femoral notch volumeand each of these volumes normalised by tibial plateau area were compared between the ACL-injured andthe ACL-intact group. Fifty-one athletes undergoing unilateral anatomical ACL reconstruction (17 female, 34 male: average age 22.0 ± 7.5) and 19 healthy collegiate athletes with no previous knee injury (eight female, 11 male: average age 20.1 ± 1.3) were included in this study. The whole tibial spine volume in the ACL-injured group(2.1 ± 0.5 cm3) was 20.7% smaller than in the ACL-intact group (2.7 ± 0.7 cm3) (p = 0.005). No differences were observed between the femoral notch volume in the ACL-injured group(9.5 ± 2.1 cm3) and the ACL-intact group (8.7 ± 2.7 cm3) (n.s.). The main finding of this study was that the whole tibial spine volume of the ACL-injured group was smaller than the ACL-intact group. A small tibial spine volume can be added to the list of anatomical risk factors that may predispose athletes to ACL injury. Level Ⅲ.

Magnetic Resonance Imaging-Based Morphometric Analyses of the Bicruciate Injury of the Knee: Is There a Clue in the Distal Femur?

The morphology of the distal femur's intercondylar notch has been implicated in the susceptibility to and severity of cruciate ligament injuries. While previous research has primarily focused on isolated anteriorcruciate ligament (ACL) or posterior cruciate ligament (PCL) injuries, the relationship between notch morphology and combined cruciate injuries remains less understood. This study aimed to explore the association between femoral notch morphology and the severity of combined cruciate ligament injuries in adult males. In this retrospective cohort study, MRI scans from 118 adult male participants with and without knee dislocations (60 cases with Schenk classification Type II or higher knee dislocations and 58 controls) were analyzed. The study period ranged from 2015 to 2023. Femoral notch width, notch width index (NWI), and notch shape (U shape, A shape) were assessed using a Philips Multiva 1.5 Tesla system (Philips, Amsterdam, Netherlands). The statistical significance of differences in measurements between cases and controls was evaluated using independent sample t-tests performed with IBM SPSS Statistics, version 26 (IBM Corp., Armonk, NY). The case group exhibited a significantly smaller mean femoral notch width (15.88 mm ± 2.7 mm) and NWI (0.238 ± 0.58) compared to the control group (notch width 18.29 mm ± 3.4 mm, NWI 0.25 ± 0.31), with p-values of 0.004 for both measurements. The notch shape was predominantly A-shaped in the case group (n = 49) as opposed to U-shaped in the control group (n = 41). The study identifies a significant association between reduced femoral notch dimensions and the severity of complex cruciate ligament injuries. These findings support the notion that specific femoral notch morphologies may predispose individuals to more severe ligamentous injuries.

Increased lateral femoral condyle ratio measured by MRI is associated with higher risk of solitary meniscus injury.

Background: Past studies found that an increased lateral femoral condyle ratio is associated with anterior cruciate ligament injuries, but it is not clear if there is a link between MRI-measured lateral femoral condyle ratios and meniscal injuries. MRI provides a more accurate selection of measurement planes. Compared to X-rays, it further reduces data errors due to non-standard positions. Objective: To study the relationship between knee bone morphology and Solitary meniscal injuries by MRI. Methods: A total of 175 patients were included in this retrospective case-control study, including 54 cases of pure medial meniscus injury, 44 cases of pure lateral meniscus injury as the experimental group, and 77 control subjects. MRI images were used to measure the femoral notch width, femoral condylar width, femoral notch width index, lateral femoral condylar ratio (LFCR), posterior tibial slope, medial tibial plateau depth, and meniscus slope. In addition, carefully check for the presence of specific signs such as bone contusions and meniscal extrusions. Comparing the anatomical differences in multiple bone morphologies between the two groups, a stepwise forward multifactorial logistic analysis was used to identify the risk factors for Solitary meniscal injuries. Finally, ROC curves were used to determine the critical values and best predictors of risk factors. Results: MTS, LTS, and LFCR ended up as independent risk factors for meniscus injury. Among all risk factors, LFCR had the largest AUC of 0.781 (0.714-0.848) with a threshold of 72.75%. When combined with MTS (>3.63°), diagnostic performance improved with an AUC of 0.833 (0.774-0.892). Conclusion: Steep medial tibial plateau slope, steep lateral tibial plateau slope angle, and deep posterior lateral femoral condyles on MRI are independent risk factors for meniscal injuries. In patients with knee discomfort with the above imaging findings (X-ray, MRI), we should suspect and carefully evaluate the occurrence of meniscal injuries. It not only provides a theoretical basis to understand the mechanism of meniscus injury but also provides theoretical guidance for the prevention of meniscus injury and the development of intervention measures. Level of evidence III.

Robot-Assisted Patellofemoral Arthroplasty.

Patellofemoral arthroplasty is indicated in patients with isolated patellofemoral arthritis in whom nonoperative treatment has failed2. The goal of the presently described procedure is to provide relief from patellofemoral arthritis pain while maintaining native knee kinematics2. Patient radiographs are carefully reviewed for isolated patellofemoral arthritis in order to determine the appropriateness of robotic-assisted patellofemoral arthroplasty. Magnetic resonance imaging can be performed preoperatively to help confirm isolated patellofemoral arthritis. We perform this procedure with use of the MAKO Surgical Robot (Stryker). Preoperative computed tomography is performed to plan the bone resection, the size of the implant, and the positioning of the device. The steps of the procedure include (1) medial parapatellar arthrotomy, (2) intraoperative inspection to confirm isolated patellofemoral arthritis, (3) patellar resurfacing, (4) placement of optical arrays and trochlear registration, (5) trochlear resection, (6) trialing of implants, (7) removal of the optical array, (8) impaction of final implants, (9) confirmation of appropriate patellar tracking, and (10) closure. Alternatives to patellofemoral arthroplasty include standard nonoperative treatment, bicompartmental arthroplasty, total knee arthroplasty, tibial tubercle osteotomy, partial lateral facetectomy, and arthroscopy2. Patellofemoral arthroplasty is indicated in patients with isolated patellofemoral arthritis in whom nonoperative treatment has failed2. Patellofemoral arthroplasty may be superior to total knee arthroplasty because it helps treat pain that affects patient quality of life and activities of daily living while also preserving greater tibiofemoral bone stock2. We recommend against performing patellofemoral arthroplasty in patients with arthritis of the tibiofemoral joints2. In properly selected patients, outcomes include improvement in patient pain and function1. One study found that robotic-assisted patellofemoral arthroplasty may result in improved patellar tracking compared with non-robotic-assisted patellofemoral arthroplasty1; however, functional outcomes were found to be similar between procedures, and data for all non-robotic-assisted controls were retrospectively captured1. Confirm isolated patellofemoral arthritis on radiographs and/or magnetic resonance imaging.Review the preoperative plan for appropriate positioning of the trochlear implant.○ Confirm coverage of the trochlear groove.○ Avoid medial overhang.○ Avoid lateral overhang.○ Avoid anterior femoral notching.○ Avoid impingement of the trochlear component into the notch.○ Avoid excessive prominence of the trochlear component on the anterior femoral cortex.○ General principles are to place the trochlear component in 0° to 6° of flexion and 0° to 2° of external rotation.Robotic-assisted trochlear resurfacing is accurate and efficient. CT = computed tomography.

Robotic-assisted total knee arthroplasty results in decreased incidence of anterior femoral notching compared to posterior referenced instrumented total knee arthroplasty.

Periprosthetic fracture (PPF) is an uncommon but devastating complication after total knee arthroplasty (TKA). Anterior femoral notching (AFN) is one of a perioperative risk factor for PPF. The main purpose of this study was to compare between the rates of anterior femoral notching (AFN) and supracondylar periprosthetic femoral fracture (sPPF) of manual TKA and robotic arm-assisted TKA (RATKA). Meanwhile, blood loss, transfusion rates, inflammatory responses, complications, early clinical and radiological outcomes were also assessed. This retrospective study included 330 patients (133 RATKA and 197 manual TKA). Differences in risks of inflammatory, blood loss, complications (periprosthetic fracture and periprosthetic joint infection), pre-operative and post-operative distal lateral femoral angle (LDFA), distal femoral width (DFW), prosthesis-distal femoral width (PDFW) ratio, AFN, femoral component flexion angle (FCFA), peri-operative and post-operative functional outcomes between the RATKA and manual TKA groups were compared. The operation time and postoperative CRP level in the RATKA group was significantly longer and higher than that in the manual TKA group (p < .001). However, there was no significant difference in postoperative WBC level (p = .217), hemoglobin loss (p = .362), postoperative drainage (p = .836), and periprosthetic fracture (p = 1.000). There was no significant difference in LDFA (p > .05), DFW(p = .834), PDFW ratio (p = .089) and FCFA (p = .315) between the two groups, but the rate of AFN in the RATKA group was significantly lower than that in the manual TKA group (p < .05). There was no significant difference in ROM between the two groups on POD3, POD 90 and 1 year (p < .05), but the FJS-12 score in the RATKA group was higher than that in the manual TKA group on 1 year (p = .001). Robotic-assisted total knee arthroplasty can decrease the incidence of anterior femoral notching compared to posterior referenced instrumented total knee arthroplasty.

Satisfactory Short‑Term Outcomes of Condylar‑Constrained Knee Implants in Primary Total Knee Arthroplasty

Background: This research set out to assess the functional prognosis of constrained condylar knee (CCK) in patients with severe intraoperative instability and/or coronal deformity undergoing primary total knee arthroplasty (TKA). Materials and methods: A prospective cohort study including 25 knees (21 cases) who underwent primary TKA using CCK implants. Senior surgeon operated all patients during 2020/2021 and followed clinically and radiographically at three, six and 12 months and 2 years postoperative. All cases were implanted with a single-design, second-generation CCK implant with a mean follow-up of 2 years. Results: The current research involved 25 knees (21 patients) with mean age 62.8 ± 12.2 years and most of the included patients were females (19; 76%). Preoperatively, valgus was demonstrated in six patients (24%) while varus was reported in 19 patients (76%) with mean preoperative Valgus/Varus angle 24.4 ± 9.9. Mean preoperative Knee Society Score (KSS) was 13.2 ± 2.7, mean preoperative functional KSS was 23.8 ± 19.2 and mean preoperative range of movement (ROM) was 107 ± 19.2. After 6 months, mean values of KSS was 86.2 ± 7.59. After 1 year, 2 years &amp; over 2 years, mean values of KSS were 86.2 ± 7.6, 86.2 ± 7.5, 86.3 ± 7.7 respectively. Degree of change in KSS before and after the operation was 69.1 ± 20.9. Mean values of late functional KSS was 62.5 ± 23.3. Degree of change in functional KSS before and after the operation was 36.8 ± 19.1. Postoperative ROM mean value was 120 ± 6.9 with degree of change 12.8 ± 6.3. Three cases reported postoperative complications; one cellulitis, one anterior femoral notching and one peroneal nerve injury. KSS increased from baseline to early postoperative with statistically significant variances (p&lt; 0.001) however, no statistically significant changes were discovered in KSS from early postoperatively to 2 years of follow up. Conclusion: Primary TKA utilizing CCK implants in cases with severe coronal abnormalities and/or intraoperative instability had a good short-term survival rate, on par with less limited implants. With positive clinical and radiological results, CCK implants can be thought of as a good alternative in some instances. It is important to exercise caution while utilizing an elevated level of restraint, since less restricted implants should be preferred.

Reduction of a Depressed Femoral Lateral Notch at the Time of Lateral Extra-articular Tenodesis

We present a surgical technique to address severe lateral femoral notch depressions using a small extension in the lateral approach for Lemaire extra-articular tenodesis in anterior cruciate ligament reconstruction. Through this approach, the surgeon is able to obtain good exposure of the lateral femoral condyle, with straightforward access for subchondral reduction, without adding any significant morbidity.

An anthropometric study of intercondylar femur notch with MRI analysis

Background: Anterior cruciate ligament is the most common ligament injury of knee. The bony anatomy of femur and tibia is responsible for normal knee kinematics and static stability. Intercondylar notch dimensions is considered as a significant predictive risk factor for ACL tear. Narrow femoral intercondylar notch width in either sex were major correlating factors. Aim was to evaluate the intercondylar femur notch dimensions in patients of knee injury using magnetic resonance imaging at RD Gardi Medical College, Ujjain, Madhya Pradesh. Methods: This is a prospective study consist of 400 patients carried out from October 2020 to August 2022 in the Department of Orthopaedics, RDGMC Ujjain. All the patients of knee injury including ACL tear and age 18 years to 60 years are included in the study. Patient less than 18 years and more than 60 years were excluded from the study. Dicom radiant software is used as statistical tool to analyse the data. Various intercondylar notch dimensions in different sections are measured using MRI in the dicom software. Results: The cut off values of axial NWI, NSI, NDI as 0.238, 0.662, 0.472 respectively. Conclusions: We conclude that narrow femoral intercondylar notch, lower notch width index increases the risk of an ACL tear in the given population. This would help in identification of people at risk for ACL injuries. Our study provides a comprehensive analysis on the risk factor of ACL tear, which would help in betterment of the patients at danger for anterior cruciate ligament injury. People with decreased notch dimensions should be educated on the high risk of ACL tear and be given proper prophylactic precautions.

Could medial femoral notching be a marker in posterolateral corner injuries?

IntroductionPosterolateral corner (PLC) injuries constitute 16 % of all knee ligament injuries and are often seen with other ligamentous injuries. PLC injuries can be overlooked. If left untreated, other ligamentous reconstructions are at risk, residual laxity may occur, and early osteoarthritis may result. Materials and methodsPatients diagnosed with PLC injury and who underwent surgical treatment between November 2018 and November 2022 were retrospectively analyzed. Two groups were formed 44 PLC patients with a concomitant ligament injury and 50 patients with an isolated ACL injury (control group). Preoperative MRI findings and arthroscopic surgery findings of the patients were evaluated. Medial femoral condyle notching sign (MFNS) and lateral femoral condyle notching sign (LFNS) data were obtained from preoperative MRI sections. If the lesion depth was less than 1.5 mm, it was not considered a notching sign. ResultsIn group 1, there were 44 patients with PLC injuries accompanied by other ligamentous injuries. In group 2, there were 50 patients with isolated ACL injuries not accompanied by other ligamentous injuries. Medial femoral notching sign (MFNS) was higher in Group 1 (p < 0.00001). The lateral femoral notching sign (LFNS) was higher in Group 2 (p:0.023). ConclusionPLC injuries are difficult to diagnose. MFNS is a finding that may facilitate diagnosis in PLC injuries.

Lateral femoral chondral lesions are more frequent when an anterior cruciate ligament tear is concomitant with a lateral femoral notch sign, but do not progress over time

BackgroundThe lateral femoral notch sign (LFNS) is caused by an impact to the lateral femoral condyle during a pivot shift injury and affects 25% to 33% of patients with an anterior cruciate ligament (ACL) rupture. The primary aim of this study was to compare the incidence of chondral lesions 1year after ACL reconstruction, while taking into consideration preoperative chondral damage, in patients with and without a preoperative LFNS. The primary outcome measure was the presence of chondral lesions involving the lateral femoral condyle, confirmed on magnetic resonance imaging (MRI) using the Outerbridge classification, at 1year postoperative. The secondary outcome measures were bone bruise of the lateral femoral condyle confirmed on MRI, the International Knee Documentation Committee (IKDC), Lysholm and Tegner functional scores taken 1year after surgery. MethodsSixty patients were included—30 with preoperative LFNS and 30 without—in a retrospective, comparative study of prospectively collected data on patients operated between August 2018 and December 2020. ResultsA lateral femoral chondral lesion 1year after surgery was significantly more common in the group with a preoperative LFNS (37% [n=11] versus 13% [n=4] in the group without a preoperative LFNS, p=0.036). Adjusting the statistical analysis for preoperative body mass index (BMI) did not impact these results (adjusted odds ratio [OR]=3.83 [95%CI: 1.03–14.24]; p=0.045). Adjusting for a preoperative lateral femoral chondral lesion had an impact on these results (adjusted OR=0.78 [95%CI: 0.12–5.08]; p=0.793). This indicates that a preoperative LFNS is not significantly and independently associated with a lateral femoral chondral lesion at 1year postoperative when the analysis is adjusted for a preoperative lateral femoral chondral lesion. However, having a preoperative lateral femoral chondral lesion is significantly correlated with the presence of a lateral femoral chondral lesion 1year after the surgery (adjusted OR=63.31 [95%CI: 5.94–674.8]; p=0.001). There were no significant differences in terms of bone bruise on MRI (p=1.0), or for the IKDC (p=0.310), Lysholm (p=0.416) and Tegner (p=0.644) functional scores. The LFNS was still present in 21 out of 30 patients (70%) at 1year postoperative. The preoperative LFNS was significantly smaller in the group without a chondral lesion compared to the group with a chondral lesion 1year after the surgery (median=2.30mm [IQR: 1.40; 3.00] versus 3.10mm [IQR: 2.50; 3.40]; p value=0.045). ConclusionsPatients with a preoperative LFNS are three times more likely to have a chondral lesion in the notch region 1year after surgery. These chondral lesions are concomitant to the injury and do not progress over time. Level of evidenceIII.