Posterior Tibial Slope Research Articles

Increased posterior tibial slope leads to altered pressure distribution in the lateral tibial plateau-A biomechanical in-vitro study.

The aim of this study is to investigate the impact of increased posterior tibial slope (PTS) on pressure distribution in the medial and lateral tibial plateau. The focus is on compartment-specific effects and potential correlations with cartilage damage, due to altered anterior tibial translation caused by increased PTS. Ten freshly frozen knee specimens were prepared and subjected to biomechanical testing. PTS was modified by inserting 5°, 10°, 15° and 20° polylactic acid wedges into osteotomy gaps. Pressure distribution was measured using Tekscan's Pressure Mapping Sensor 5040™ beneath the menisci at varying PTS angles. The kinetic data were tracked using the Optotrak Certus® system. Statistical analyses were employed to evaluate the pressure shifts and their significance. The study revealed that increased PTS significantly shifted the pressure point anteriorly on the lateral tibial plateau, while no significant changes were observed on the medial plateau. The analysis of tibial translation showed a corresponding rise in anterior translation with increasing PTS, especially at higher angles. Increased PTS, particularly above 10°, induces significant anterior translation and altered pressure distribution, primarily affecting the lateral tibial plateau. These findings support the hypothesis that elevated PTS contributes to biomechanical stresses in the knee, potentially increasing the risk of lateral compartment cartilage degeneration. These results highlight the importance of considering PTS in clinical assessments and interventions aimed at optimizing knee joint health. Level IV.

Intraoperative reference points on the proximal tibia in image-free robotic-assisted total knee arthroplasty should be determined by preoperative posterior tibial slope.

The purpose of this study was to investigate the accuracy of the tibial cut in sagittal plane and intraoperative optimal reference points on the proximal tibia for achieving the targeted posterior tibial slope (PTS) in image-free, robotic-assisted total knee arthroplasty (TKA). A mechanical tibial axis determined by intraoperative reference points would affect the measurement of the PTS and thereby postoperative PTS in image-free robotic assist TKA. Fifty-eight patients (70 knees) who underwent primary image-free robotic-assisted TKA were included. Pre- and postoperative PTS were evaluated using whole-leg computed tomography images, which were analysed with three-dimensional planning software. Change in PTS (ΔPTS) was calculated by subtracting the target PTS from postoperative PTS. The proximal tibial axis ratio was defined as the proportion of distance between the anterior border of the anterior cruciate ligament (ACL) footprint and the tibial axis on the proximal joint surface to the anteroposterior width of the ACL footprint. The mean ΔPTS was -0.4 ± 2.0 °. Eight outliers (11.4%; |ΔPTS| >3°) were identified. The proximal tibial axis ratio was -13.2 ± 19.9% and showed a significant negative correlation with preoperative PTS and ΔPTS (r=-0.87 and -0.29, p < 0.001 and p = 0.01, respectively). The tibial axis passed through the anterior border of the ACL footprint when preoperative PTS was 9.6 °. These results indicated that a larger preoperative PTS was associated with a more anterior tibial axis on the proximal joint surface. Preoperative PTS significantly correlated with ΔPTS (r = 0.34 and p = 0.004). In image-free robotic-assisted TKA, when the preoperative PTS is >9.6 °, positioning the proximal tibial reference point anterior to the anterior border of the ACL footprint is recommended. III.1.

Comparative Analysis of Posterior Tibial Slope Measurements: Accuracy and Reliability of Radiographs and CT

Comparative Analysis of Posterior Tibial Slope Measurements: Accuracy and Reliability of Radiographs and CT

Radiological characteristics of the knee in young patients with medial meniscus horizontal tears.

We aimed to assess medial meniscal (MM) healing and horizontal tear (HT) repair in the knees of young patients. We enrolled 37 knees of 35 patients (mean age: 28.0 ± 10.2 years) with isolated meniscal repair that were divided into three groups: MM HT group (HT group, n = 15), MM tear except for HT group (MM group, n = 11), and lateral meniscus (LM) tear except for discoid meniscus group (LM group, n = 11). The anatomical lateral distal femoral angle (aLDFA), medial proximal tibial angle (MPTA), and posterior tibial slope were measured on preoperative radiographs. Magnetic resonance imaging was performed at 3, 6, and 12 months post-surgery. Clinical outcomes were evaluated using Lysholm and Knee Injury and Osteoarthritis Outcome Score (KOOS) at 24 months post-surgery. aLDFA values were significantly lower in the HT and MM groups than in the LM group (P = .007). The MPTA was significantly lower in the HT group than in the MM and LM groups (P = .000). There were no differences in meniscal healing among the three groups at any time point after surgery (P = .376, .830, and .523, respectively). The KOOS subscale scores, symptom, pain, sports and recreation, and quality of life in the HT group were significantly lower than those in the LM group (P = .021, .033, .035, and .041, respectively). Young patients with MM HT have small aLDFA and MPTA values. Although the healing rate of HT post-repair was comparable to other types of MM or LM tears up to 1 year post-repair, clinical outcomes (KOOS) of repaired HTs were inferior to those of LM tears 2 years post-repair.

Guiding significance of intra-articular sagittal reduction in the treatment of tibial plateau fractures

Tibial plateau fracture is a fracture involving the proximal articular surface of the tibia, and its injury mechanism is complex, the fracture morphology is different, and it is often accompanied by different degrees of soft tissue injury, which is difficult to diagnose and treat. In recent years, the research hotspot has focused on solving the reduction and fixation of the posterior lateral column of the tibial plateau, because it has been clinically found that the residual sagittal plane after tibial plateau fracture is insufficient reduction or loss of reduction leads to knee joint dysfunction. The posterior inclination angle of the tibial plateau is an important parameter to describe the sagittal alignment of the tibia. In the natural state, the posterior tibial slope(PTS) is altered to involve the soft tissues around the knee joint such as anterior cruciate ligament(ACL) and posterior cruciate ligament(PCL), which affects the stability of the knee joint. In total knee arthroplasty(TKA), choosing the appropriate PTS can effectively increase the prosthesis survival rate, improve the flexion and extension knee efficacy, which is beneficial to knee joint stability. In the field of orthopedic trauma, correction of sagittal deformity is equally important, following the principle of "reverse mechanism of injury". Quantitative evaluation of postoperative sagittal realignment of tibial plateau fractures and investigation of the effect of sagittal realignment on long-term outcomes and complications are still poorly understood and require further clinical and biomechanical studies.

Posteromedial opening wedge high tibial osteotomy has favourable outcomes in simultaneous medial meniscus posterior root repair and varus medial knee osteoarthritis patients without concomitant root tear

PurposeTo evaluate the radiological and clinical outcomes in two patient groups: first, varus aligned medial meniscus posterior root tear (MMPRT) patients who underwent posteromedial open wedge high tibial osteotomy (PMOWHTO) and simultaneous root repair; second, patients with varus medial knee osteoarthritis without MMPRT who underwent PMOWHTO.MethodsPatients had MMPRT repair concomitant with PMOWHTO and varus medial knee osteoarthritis without concomitant root tear patients who underwent PMOWHTO and were reviewed. Radiographic parameters, medial meniscus extrusion (MME) and Knee Society Scores [KSSs, including the following subscores: knee score (KS) and knee function score (KFS)] were evaluated. Continious variables are expressed as the median and interquartile range (IQR) [IQR: (Q1;Q3); Q1: median of lower half, Q3: median of upper half]. The minimum follow-up period was 24 months [29 (28;35) months].ResultsA total of 36 knees of 34 patients underwent PMOWHTO were included. Patients were divided into two groups according to the presence or absence of a MMPRT. Nineteen of the 36 knees had MMPRTs, and all of them had concomitant root repair (Group 1). Seventeen of the 36 patients did not have MMPRTs (Group 2). The posterior tibial slope (PTS) decreased postoperatively in a total of 36 knees (p < 0.001). There were no significant changes in MME postoperatively in any intragroup comparison. The preoperative and follow-up MMEs of Group 1 were greater than those of Group 2 (p < 0.001). The KSs and KFSs in both Group 1 and Group 2 increased during follow-up [KS; Group 1: 43 (36;53) vs. 86 (84;95), p < 0.001. Group 2: 49 (45;57) vs. 89 (80;93), p < 0.001. KFS; Group 1: 60 (50;60) vs. 90 (80;100), p < 0.001. Group 2: 60 (50;60) vs. 80 (80;90), p < 0.001]. All knees achieved minimal clinically important difference (MCID) in terms of KSs. Eighteen (95%) knees achieved MCID in Group 1, and 17 (100%) achieved MCID in Group 2 in terms of KFSs. There were no differences between Groups 1 and 2 in terms of preoperative and follow-up KSs or preoperative KFSs. The follow-up KFSs in Group 1 was significantly greater than that in Group 2 (p = 0.032).ConclusionsPMOWHTO has favourable clinical and radiological outcomes and prevents PTS increase in simultaneous MMPRT repair and varus medial knee osteoarthritis patients without concomitant root tear.Level of evidenceLevel IV, case series.

Hinge Position Dominance Over Osteotomy Inclination in Medial Open-Wedge High Tibial Osteotomy: A Key Factor in Posterior Tibial Slope Changes.

A medial open-wedge high tibial osteotomy (MOWHTO) may increase the posterior tibial slope (PTS). The purpose of this study was to determine the effect of the osteotomy inclination angle (in the sagittal plane) in combination with different hinge positions (in the transverse plane) on the change in PTS due to a MOWHTO. We developed a mathematical approach to determine the effect of the osteotomy inclination angle combined with different hinge positions. The change in PTS was determined for different osteotomy inclination angles, hinge positions, and intended wedge angles. Anterior-inclined, parallel, and posterior-inclined osteotomy inclination angles were simulated. Hinge positions varied between 5° anterolateral and -45° posterolateral. The wedge angles were 5°, 10°, and 15°. Moreover, 2 in silico osteotomies were performed to verify the results of the mathematical model. The PTS was maintained when the osteotomy cut was performed parallel to the tibial plateau with a lateral hinge position. The PTS changed when the osteotomy was not aligned in the sagittal plane, ranging between 0.0° and 0.6°. Different hinge positions, however, had a large effect on postoperative PTS change, ranging between 0.1° and 10.7°. Our mathematical approach showed that the hinge position has a strong effect on the PTS. The sagittal osteotomy inclination angle had little effect on the PTS. An inclination angle parallel to the medial tibial plateau combined with a lateral hinge position does not change the PTS.

Relationship between knee meniscus and posterior tibial slope in healthy adults and patients with anteromedial osteoarthritis in Heilongjiang province

To measure and analyze the relationships among the posterior tibial slope (PTS), meniscal slope (MS), and meniscus posterior horn thickness (MPHT) of the medial and lateral tibial plateau in healthy people and patients with anteromedial osteoarthritis (AMOA) in Heilongjiang province, so as to provide reference basis for appropriate tibial osteotomy and prosthesis placement angles in knee joint surgeries. A retrospective collection of imaging data from knee joint MRI examinations conducted prior to AMOA for various reasons was performed. A total of 103 healthy individuals (healthy group) and 30 AMOA patients (AMOA group) were included. There was no significant difference in the gender composition ratio, side, and body mass index between the two groups ( P>0.05); however, the comparison of ages between the two groups showed a significant difference ( P<0.05). The collected DICOM format image data was imported into the RadiAnt DICOM Viewer software and measured the medial PTS (MPTS), lateral PTS (LPTS), medial MS (MMS), lateral MS (LMS), medial MPHT (MMPHT), and lateral MPHT (LMPHT) with standard methods. The differences of the above indexes between the two groups and between different genders and sides in the two groups were compared, and Pearson correlation analysis was carried out. At the same time, the measured data of healthy group were compared with the relevant literature reported in the past. Compared to the healthy group, the AMOA group exhibited significantly smaller MPTS and LPTS, as well as significantly greater MMPHT and LMPHT, with significant differences ( P<0.05). However, there was no significant difference in the MMS and LMS between the two groups ( P>0.05). The differences in various indicators between genders and sides within the two groups were not significant ( P>0.05). The correlation analysis and regression curves indicated that both MPTS and LPTS in the two groups were positively correlated with their respective ipsilateral MS and MPHT ( P<0.05); as PTS increased, the rate of increase in MS and MPHT tend to plateau. Compared to previous related studies, the MPTS and LPTS measured in healthy group were comparable to those of the Turkish population, exhibiting smaller values than those reported in other studies, while MMS and LMS were relatively larger, and MMPHT and LMPHT were smaller. In healthy people and AMOA patients in Heilongjiang province, PTS has great individual differences, but there is no significant individual difference in MS. MPHT can play a certain role in retroversion compensation, and its thickness increase may be used as one of the indicators to predict the progression of AMOA. The above factors should be taken into account when UKA is performed, and the posterior tilt angle of tibial osteotomy should be set reasonably after preoperative examination and evaluation.

Correlation of Increased Lateral Tibial Slope With Baseline Tibial Position in Intact Knees and Side-to-Side Anterior Tibial Translation for Knees With ACL Tears.

Anterior cruciate ligament (ACL) stress techniques-including single-leg stress radiographs, Telos, and KT-1000 arthrometer-are highly accessible and can provide additional diagnostic information to assess ACL and ACL graft integrity. The degree of anterior tibial translation (ATT) may be useful in guiding treatment when a diagnosis on magnetic resonance imaging is not conclusive or for judging if additional treatments, such as anterolateral complex augmentation, may be necessary. The purpose of this study was to evaluate the effect of increasing posterior tibial slope (PTS) on baseline tibial position (BTP) and side-to-side differences (SSD) in ATT. A secondary purpose was to perform a subgroup analysis of SSD in ATT for patients with a PTS of ≥12° versus <12°, as well as for acute (<6 weeks from injury) versus chronic (≥6 weeks from injury or ACL graft tear) ACL tears. It was hypothesized that the BTP in normal intact knees would increase linearly with the PTS and there would be an increased SSD in ATT when comparing ACL-injured and ACL-intact knees. Case-control study; Level of evidence, 3. Bilateral ACL stress radiographs were assessed from patients with primary ACL and ACL graft tears between March 2023 and March 2024. Bilateral stress views were obtained by single-leg full-length lateral weightbearing radiograph in 20° of knee flexion. The BTP and ATT were measured using a perpendicular line drawn between the posterior position of the lateral femoral condyle and the lateral tibial plateau. PTS measurements were assessed by the anatomic tibial axis. Statistical analysis using linear regression-r > 0.6 was considered strong, r between 0.4 and 0.6 moderate, and r < 0.4 weak-and t tests were used to compare the PTS with BTP and SSD in ATT. A total of 72 patients were analyzed using ACL stress radiographs. The results found a significant positive correlation between increased PTS and increased BTP for the ACL-intact knees (P < .001; r = 0.476). A significant increase was found in the SSD in ATT of 1.73 mm with a positive correlation between increased PTS and increased SSD in ATT of ACL-deficient knees (P < .001; r = 0.397). A subgroup analysis reported significant increases in SSD in ATT for both ACL-injured knees with a PTS ≥12° (P = .008) and for chronic ACL tears (P < .001) and no significant differences in SSD in ATT for ACL-injured knees with a PTS of <12° (P = .650) and for acute ACL tears (P = .745). This study found a significant positive correlation between PTS and the BTP in ACL-intact knees and for the SSD in ATT between ACL-injured and ACL-intact knees. Moreover, the SSD in ATT was significantly increased for ACL-injured knees with a PTS of ≥12° and for chronic ACL tears. No significant difference in SSD in ATT was found for ACL-injured knees with a PTS of <12° and for acute ACL tears.

The Impact of Tibial Slope on Anterior Cruciate Ligament Reconstruction Outcomes – University Hospital Study

Anterior cruciate ligament (ACL) injuries are common knee injuries that often require surgical reconstruction to restore knee function and stability. Despite advances in surgical techniques, the failure rate for ACL reconstruction remains approximately 15%, emphasizing the need to understand factors contributing to suboptimal outcomes. One factor that has garnered attention is the tibial slope, particularly the posterior tibial slope (PTS), which may influence ACL injury and graft failure. Biomechanical studies suggest that an increased PTS can elevate anterior tibial translation, potentially increasing stress on the ACL and raising the risk of both primary ACL injury and graft failure. However, the clinical significance of tibial slope in ACL reconstruction outcomes remains debated. This retrospective study investigates whether an increased PTS is associated with a higher likelihood of revision surgery or poor surgical outcomes. A total of 152 patients who underwent primary ACL reconstruction or revision surgery between 2018 and 2022 with at least two years of follow-up were included. Tibial slope measurements were obtained from lateral tibial radiographs, and patients were categorized into three groups based on post-surgical outcomes: Group A (successful return to prior sport levels), Group B (stable knee without return to sport), and Group C (requiring revision surgery). The Mann-Whitney U test was used to compare tibial slope measurements across groups. No significant differences were found in tibial slope between the groups (p &gt; 0.05). Group A had a median tibial slope of 6.08°, Group B had 6.68°, and Group C had 5.85°. These findings suggest that tibial slope may not be a major factor influencing ACL reconstruction success or failure. Other factors, including surgical technique, rehabilitation, and patient-specific characteristics, may play more significant roles. Further research is needed to explore the relationship between tibial slope and ACL ...

Evaluating the Mechanical Axis for Detection of Posterior Tibial Slope Malalignment in ACL-Deficient Knees on Lateral Radiographs.

Distal tibial deformities are not assessed using the proximal anatomical axis (PAA) to determine the posterior tibial slope (PTS). Therefore, it seems advantageous to measure PTS on full-length lateral tibial radiographs using the mechanical axis (MA). To (1) compare the PTS measurements using the MA and the PAA and (2) determine whether using the PAA fails to detect a certain number of significantly elevated PTS values compared with using the MA. Cohort study (Diagnosis); Level of evidence, 3. Full-length lateral tibial radiographs of 218 consecutive cases were reviewed. Radiographs were checked for malrotation. Therefore, the distance between the posterior tibial condyles was measured in millimeters. Patients with a difference of ≥7 mm between the posterior tibial condyles were excluded, leaving 196 cases for the final statistical analysis. The PTS was measured using the MA and the PAA. Differences between these 2 techniques were analyzed. The sensitivity and specificity of the PAA as a screening method for pathological PTS were calculated, with the MA as the standard for comparison. Four subgroups were formed, all with PAA <12° and different lower limits for the MA: group 1, MA ≥10°; group 2, MA ≥10.5°; group 3, MA ≥11°; and group 4, MA ≥11.5°. Radiographs with ≥7 mm between the posterior tibial condyles showed an increased inconsistency between the PTS measurement with the MA and the PAA. In the group with a distance of <7 mm between the posterior tibial condyles (n = 196), the mean PTS measured with the MA was 9.4°± 3.8° (range, 0.4° to 21.9°), and the mean PTS was 10.5°± 3.5° (range, 1.7° to 20.9°) according to the PAA. The mean difference in PTS between the PAA and the MA was 1.1°± 1.2° (range, -2.4° to 4.1°; P < .001). Group 1 had a sensitivity of 73% and specificity of 98%; group 2, sensitivity of 84% and specificity of 97%; group 3, sensitivity of 87% and specificity of 93%; and group 4, sensitivity of 95% and specificity of 89%. Measuring the PTS using the MA was advantageous, as the measurement with the PAA did not correctly identify all cases with sagittal alignment changes. The proportion of patients with pathologically increased PTS not identified with the proximal anatomical measurement, reflected by the sensitivity, depended on the threshold value defined for the MA. Lateral radiographs, showing an increased distance between the posterior tibial condyles, indicated malrotation of the tibia leading to measurement inaccuracy.

The use of four K-wires does not lead to a reduction of the MPTA in the context of a one-dimensional tibial deflection correction of patients with ACL re-rupture and pathologically increased tibial slope.

Anterior tibial closing wedge osteotomy (ATCWO) has been shown to significantly reduce failure rates of revision anterior cruciate ligament (ACL) reconstructions in patients with a posterior tibial slope (PTS) ≥12°. Recent findings suggest a slight but significant reduction of the medial proximal tibial angle (MPTA) resulting in a varus knee where the sagittal osteotomy plane is based on a total of two guide wires defining the osteotomy wedge without respecting the frontal plane. We hypothesize that the placement of a total of four guide wires intraoperatively can reduce the influence on the MPTA. This study retrospectively reports on a two-centre series of 42 ATCWOs for PTS correction between January 2022 and December 2023 at two clinical centres. A total of four guide wires were placed based on a true lateral intraoperative view of the tibia, with two positioned each at the cranial and at the caudal pole of the osteotomy wedge, serving as guides for the saw to create the osteotomy, with careful attention to ensuring that the proximal and distal K-Wires were placed parallel to each other. A retrospective analysis was conducted by examining true lateral and anteroposterior radiographs to identify changes in sagittal and coronal plane alignment. The study included 19 women and 23 men, with a mean age of 29.7 ± 8.6 years with first-time ACL revision surgery and a minimum PTS of ≥12°. PTS decreased significantly from 14.5 ± 2.8° preoperatively to 8.2 ± 1.9° post-operatively (p < 0.001). The aMPTA demonstrated no significant difference between preoperative (mean aMPTA: 86.9 ± 2.1°) and post-operative (mean aMPTA: 86.6 ± 1.9°) measurements (p > 0.05). With our technique of placing four guide wires to achieve precise guidance during the insertion of the osteotomy wedge, there is no substantial impact on the aMPTA during slope correction. Level IV.

Patient Age and Activity Level, Posterior Tibial Slope, and Use of Allograft Are Significant Risk Factors for Anterior Cruciate Ligament Reconstruction Failure: A Systematic Review

Patient Age and Activity Level, Posterior Tibial Slope, and Use of Allograft Are Significant Risk Factors for Anterior Cruciate Ligament Reconstruction Failure: A Systematic Review

Lateral Extra-Articular Tenodesis as an Adjunct to ACL Reconstruction

Background: Lateral extra-articular tenodesis (LET) is a surgical technique used to decrease the risk of anterior cruciate ligament reconstruction (ACLR) failure by supplementing internal rotational stability and reducing pivot shift. Indications: A growing body of literature indicates that LET should be performed for patients under 25 years, those with increased posterior tibial slope and ligamentous laxity, and elite athletes in cutting and/or pivoting sports. Additional indications include patients with grade 2 pivot shift or greater and those with a history of anterior cruciate ligament graft failure. Technique Description: Surgeon preference determines LET and ACLR sequence. Anatomic landmarks are identified and marked. A 5-cm incision is made in line with the iliotibial (IT) band from Gerdy's tubercle toward the lateral epicondyle. Dissection is carried to the IT band. Approximately 1 cm from the posterior border of the IT band, a full-thickness graft of 7 to 8 cm in length and 1 cm in width is harvested proximally and then whipstitched. A varus stress applies ligamentous tension and aids in lateral collateral ligament (LCL) identification. The LCL is dissected out, and the graft is passed underneath it. An all-suture anchor placed approximately 1 to 2 cm proximal and posterior to the lateral epicondyle and the knee is positioned in neutral rotation and at approximately 60° of flexion. The graft is passed inside the suture loop with an additional knot tied over the top using the needled suture. The IT band is then repaired side to side. Remaining subcutaneous tissue and skin are closed in standard fashion based on the order of the surgery. Results: In the STABILITY randomized controlled trial, 2-year outcomes demonstrated a clinically and statistically significant decrease in clinical failure from 40% to 25% and graft rupture rate from 11% to 4% with the addition of LET to ACLR with hamstring autograft. Similar return-to-sport rate was seen between cohorts. A meta-analysis of 6 studies examining ACLR versus ACLR + LET in individuals undergoing primary ACLR reported a reduced incidence of graft failure and postoperative anterolateral rotatory instability. Discussion/Conclusion: LET is a technique that can help reduce the risk of ACLR failure. Our technique employs a knotless suture anchor to confer anterolateral rotatory stability in the setting of ACLR. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Patient-specific cutting guides allow 1° precision in asymmetric anterior closing-wedge osteotomy.

Asymmetric anterior closing-wedge high tibial osteotomy (ACWHTO) allows correction of both excessive posterior tibial slope (PTS) and varus deformity. However, the complexity of this surgery requires a high degree of accuracy, which is less likely to be achieved with standard instrumentations. This study aimed to determine the accuracy of 3D patient-specific cutting guides (PSCGs) to provide the accurate planned correction in the frontal and sagittal planes. Eight sawbones tibiae were identically printed from the same patient data. An ACWHTO with a PSCG was performed on each sawbone. Postoperative measurements of PTS, mechanical medial proximal tibial angle (mMPTA), hinge area and hinge-posterior cruciate ligament (hinge-PCL) distance were compared with the preoperative planned measurements. The precision was defined as the absolute difference (∆) between the target planned values and postoperative values. The mean accuracy was 0.6° ± 0.74° for PTS, 0.8° ± 0.71° for mMPTA, 0.3 ± 0.2 cm2 for hinge area and 0.1 ± 0.06 mm for hinge-PCL distance. In the setting of sawbones, the use of PSCGs was a reliable and accurate method of achieving simultaneous correction in the frontal and sagittal planes during asymmetric ACWHTO. Level V, basic science biomechanical laboratory study.

Combined Anterior Cruciate Ligament and Anterolateral Ligament Reconstruction Shows Superior Graft Remodeling, Maturation, and Stability Compared With Isolated Anterior Cruciate Ligament Reconstruction.

To compare graft remodeling, as measured by magnetic resonance imaging (MRI), and clinical outcomes between patients who underwent isolated anterior cruciate ligament reconstruction (ACLR) versus combined anterior cruciate ligament and anterolateral ligament reconstruction (ACLR + ALLR). A retrospective review was conducted on patients who underwent primary ACLR with quadruple hamstring grafts between January 2019 and March 2022, with a minimum follow-up period of 2 years. Patients were categorized into two groups based on the addition of ALLR with tibialis anterior allografts: an isolated ACLR group and an ACLR + ALLR group. Graft ligamentization was assessed using signal-to-noise quotient (SNQ) values obtained from postoperative MRI scans, with lower SNQ values indicating superior graft remodeling. Clinical outcomes were evaluated through knee stability tests (pivot-shift test, side-to-side laxity), functional outcomes, and graft retear rates. The minimal clinically important difference (MCID) for the clinical scores was calculated using the distribution-based method of a half standard deviation of the delta (difference between postoperative and baseline values). Regression analyses identified potential predictive factors for inferior ACL graft remodeling. A total of 122 patients in the isolated ACLR group and 54 in the ACLR + ALLR group were evaluated. The mean follow-up periods were similar between the groups (34.1 ± 7.4 months vs 36.4 ± 9.0 months; P = .755). The mean SNQ values were significantly lower in the ACLR + ALLR group compared to the isolated ACLR group (2.8 ± 1.6 vs 4.7 ± 3.5 mm, respectively; P = .001). Inferior ACL graft maturity was associated with an increased posterior tibial slope (P = .016), narrow notch width (P =.018), and concomitant medial meniscal lesion (P = .017). At the final evaluation, the ACLR + ALLR group demonstrated better rotational stability as indicated by the residual pivot-shift test (P = .005). No statistically significant differences were observed between the two groups in side-to-side laxity, functional outcomes, or graft retear rates. There were no differences in the percentage of patients achieving MCID for the International Knee Documentation Committee subjective score between the groups (P = .536). Combined ACLR and ALLR resulted in superior graft remodeling, demonstrated by a mean SNQ value that was 1.9 lower than in isolated ACLR, along with improved rotational stability. Level III, retrospective, nonrandomized, comparative therapeutic study.

The Effect of Correction Amount of Varus Deformity After Unicompartmental Knee Arthroplasty on Functional and Clinical Outcomes

Objective: This study aimed to investigate the impact of varus deformity correction on functional and clinical outcomes following unicompartmental knee surgery. Materials and Methods: A total of 71 medial unicompartmental knee arthroplasties (UKA) in 51 patients were included in this study. The knees were categorized based on the degree of correction observed in standing orthoroentgenograms post-surgery (Group 1: 0-4.9° correction, Group 2: 5-9.9° correction, and Group 3: 10° or more correction). Functional knee evaluation was assessed using range of motion measurements, posterior tibial slope angles, visual analogue score (VAS), Knee Society Score (KSS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Oxford Knee Score (OKS) questionnaires. Results: Following UKA surgery, there was a significant improvement in all patient-reported outcome scores, posterior tibial slope angles, visual analogue scores, and range of motion measurements across all groups. However, no significant differences were observed when comparing postoperative scores between the groups. Conclusion: Patients with varus deformities of up to 15 degrees can safely undergo UKA surgery without compromising clinical and functional outcomes.

Cut-off value for the posterior tibial slope indicating the risk for retear of the anterior cruciate ligament.

The significance of the posterior tibial slope (PTS) has increasingly come into focus in anterior cruciate ligament (ACL) reconstruction being a risk factor for ACL graft failure. Nevertheless, inconsistent data on the critical value of the PTS exist. The purpose of this study was to define a cut-off value for the PTS in ACL surgery. In a retrospective cohort study, 350 revision ACL reconstructions (ACL-RR) with a failed ACL hamstring graft and 350 primary ACL reconstructions (ACL-R) were matched according to age, gender, concomitant injuries and graft characteristics and compared to a healthy control group. Using the proximal anatomic axis, lateral knee radiographs were evaluated for the PTS, interrater reliability was defined, ROC curves, Fischer's exact test and Baptista-Pike method were applied to define specificity and the odds ratio for a critical PTS value. Radiographic evaluation proved excellent interrater reliability (intraclass correlation coefficient 0.969). Evaluation of the PTS revealed 10.0 ± 2.2 (5-15) degrees in the ACL-RR group, 7.8 ± 1.8 (4.2-13) degrees in the ACL-R group and 6.6 ± 1.9 (3.6-12) degrees in the control group with significant differences between the groups (p < 0.001). A PTS value of 10.1 degrees proved a specificity of 98% for the prediction of an ACL graft failure and indicated an 11-fold risk for a retear of the ACL. A PTS exceeding 10.1 degrees carries an 11-fold risk for ACL graft failure and, therefore, should be considered in ACL reconstruction. These findings might serve as a cut-off value for the indication of a slope-reducing high tibial osteotomy in ACL surgery. Level III.

The presence of a Segond fracture in ACL-injured patients is associated with increased internal tibial rotation on preoperative MRIs

BackgroundSegond fracture is considered a component of the anterolateral complex (ALC) injury, yet the underlying cause and clinical outcomes of this bony avulsion remain subjects of debate. Additionally, MRI measurements of altered tibiofemoral position in anterior cruciate ligament (ACL)-injured patients with a Segond fracture have not been reported. The purpose of this study is to measure the rotational tibiofemoral position on MRI in ACL-injured patients with a Segond fracture.MethodsA total of 44 patients with a primary ACL injury and a concomitant Segond fracture were included in the Segond fracture group, with the time from injury to MRI within 3 months. Avulsion was confirmed via preoperative computed tomography (CT) scans. The control group comprised 44 matched patients with primary ACL injury and an MRI-determined ALC injury but without a Segond fracture, also with the time from injury to MRI within 3 months. The MRI-determined ALC injury included injuries to the anterolateral ligament, Kaplan fibers, and anterolateral joint capsule, as identified based on previous studies. Sex, age, and BMI were matched between the two groups using propensity score matching (PSM). Arthroscopic findings, concomitant collateral ligament injuries, and preoperative MRI measurements were compared between the two groups.ResultsThe Segond fracture group demonstrated a higher frequency of concomitant patellar and femoral trochlear injuries (p = 0.0110) and lateral collateral ligament injuries (p = 0.0121) compared to the control group. Additionally, significantly increased internal rotational tibial subluxation (IRTS) (p = 0.0095) and axial internal tibial rotation (ITRa) (p = 0.0306) were observed in the Segond fracture group. A strong positive correlation was found between IRTS and ITRa (rp = 0.8201), indicating that these two tibial rotation measurement methods were correlated. No significant differences were observed in the measurements of anteroposterior tibiofemoral position and posterior tibial slope (PTS) between the two groups.ConclusionThe presence of a Segond fracture was associated with significantly increased internal tibial rotation measured on MRIs, suggesting that this bony avulsion may represent a more severe form of ALC injury in ACL-injured patients and should be managed with caution.

Anterior Cruciate Ligament Allograft Reconstruction in Females Can Produce Outcomes Comparable to Those of Autografts in Male Counterparts.

There are unique anatomical and geometric risk factors that contribute to higher injury rates of the anterior cruciate ligament (ACL) in women. Allografts are an important alternative option for female patients.Patients who underwent primary ACL reconstruction were retrospectively evaluated. The case group comprised female patients with ACL allograft reconstruction, and the control group comprised male patients with ACL reconstruction. Functional and clinical evaluations were based on the pre- and postoperative Cybex test, Lysholm score, International Knee Documentation Committee subjective and objective measurement criteria, and Tegner Activity Scale questionnaires. Radiological comparisons were performed using the femorotibial angle (FTA), posterior tibial slope (PTS), and intercondylar notch width (INW). The roof inclination angle (RIA) was assessed using magnetic resonance imaging.The two groups (female [44] and male [88]) had an average follow-up period of 57.9 ± 19.3 months and average ages of 36.5 ± 10.9 and 35.2 ± 11.7 years, respectively. Functional and clinical outcomes showed no differences between the groups, except that the return to the preinjury activity level was higher in the female group (95% vs. 77%, p < 0.001). The female group showed larger FTA and PTS and smaller INW and RIA than those of the male group (p < 0.001, 0.008, <0.001, and 0.035, respectively).Female ACL allograft reconstruction showed comparable outcomes to those of their male counterparts, and the return to preinjury activity levels was significantly higher in women. However, women showed lower activity levels and were more vulnerable to geometric risk factors than their male counterparts.