Risk factors for contralateral anterior cruciate ligament injury after primary anterior cruciate ligament reconstruction / 中国修复重建外科杂志

OBJECTIVE@#To investigate the risk factors of contralateral anterior cruciate ligament (ACL) injury after primary ACL reconstruction.@*METHODS@#A retrospective review was conducted on the 716 patients with ACL injury who received primary ACL reconstruction surgery and met the selection criteria between January 2012 and September 2018. After a mean follow-up period of 7.6 years (range, 4-10 years), 65 patients (9.1%) experienced contralateral ACL injury (injured group) and 651 patients (90.9%) did not (uninjured group). There was no significant difference in age, body mass index, and preoperative Lachman test degree between groups ( P>0.05). However, the proportion of female in the injured group was significantly higher than that of male ( P<0.05), and the preoperative posterior tibial slope (PTS) was significantly higher than that of the uninjured group ( P<0.05). Using the outcome of contralateral ACL injury as the dependent variable, the clinical data of the patient was first used as the independent variable, and univariate COX regression was used to analyze the prognostic influencing factors. Then, the indicators with differences in univariate COX regression were used as the independent variable, and multivariate COX regression was used to analyze the independent risk factors affecting prognosis. Log-Rank (Mantel-Cox) test was used to test and analyze the occurrence time of contralateral ACL injury in patients of different genders; X-tile software was used to analyze the occurrence time of contralateral ACL injury in patients with different PTS using Log-Rank (Mantel-Cox) test and PTS cut-off values.@*RESULTS@#Univariate COX regression analysis showed that gender and PTS were influence factors for contralateral ACL injury ( P<0.05); further multivariate COX regression analysis showed that female and increased PTS were independent risk factors for contralateral ACL injury ( P<0.05). The Log-Rank (Mantel-Cox) test results showed that the contralateral ACL injury occurred in female at 8.853 (8.600, 9.106) years, which was significantly shorter than that in male [9.661 (9.503, 9.819) years] ( χ 2=20.323, P<0.001). Using X-tile software to analyze the cut-off value of PTS, it was found that the cut-off value of PTS for contralateral ACL injury was 10.92°. According to the Log-Rank (Mantel-Cox) test, it was found that the contralateral ACL injury occurred in 5.762 (4.981, 6.543) years in patients with PTS≥10.92°, which was significantly shorter than patients with PTS<10.92° [9.751 (9.650, 9.853) years]( χ 2 =302.479, P<0.001).@*CONCLUSION@#Female and PTS≥10.92° after primary ACL reconstruction are independent risk factors for contralateral ACL injury.

Study on application of posterior tibial slope angle in anterior cruciate ligament / 中国骨伤

Posterior tibial slope angle (PTSA) is a risk factor for anterior cruciate ligament (ACL) injury and has attracted a lot of attention, but its mechanism of action and diagnosis are still not systematically studied in the field of sports medicine. In this paper, we believe that PTSA should be measured by full-length lower extremity films and combined with multiple imaging data for comprehensive assessment to reduce errors. A large PTSA may increases risk of anterior cruciate ligament injury, so patients with more than 12 degrees of PTSA should be treated by preserving meniscus as much as possible during ACL reconstruction and combining with tibial osteotomy if necessary, which could effectively prevent risk of ligament re-injury. At the same time, gait analysis has an important reference value for preoperative pathogenic pattern and postoperative rehabilitation function, so the author believes that it will have a guiding significance for the development of individualized rehabilitation strategy based on PTSA, in order to achieve the best treatment effect.

Effect of posterior tibial slope on the short-term outcome in mobile-bearing unicompartmental knee arthroplasty / 北京大学学报(医学版)

OBJECTIVE@#To evaluate the relationship between postoperative knee function and the sagittal position of tibial component in unicompartmental knee arthroplasty (UKA).@*METHODS@#We retrospectively enrolled the patients who underwent UKA from January 2016 to May 2020. They were assigned into 2 groups according to postoperative posterior tibial slope (PTS): the normal PTS group (PTS≥3° and PTS < 8°) and the abnormal PTS group (PTS < 3° or ≥8°). The patients were followed up for at least 12 months. The postoperative Knee Society Clinical Score (KSS-C), Knee Society Functional Score (KSS-F) and knee range of motion (ROM) were compared between the two groups.@*RESULTS@#A total of 72 patients (82 knees) were included with 51 patients (58 knees) in PTS normal group and 21 patients (24 knees) in PTS abnormal group. All the patients were followed up with median of 23.6 months. There was no significant difference in the general data [gender, age, body mass index (BMI)], pre-operative knee range of motion, preoperative KSS-C score and KSS-F score (P > 0.01). The KSS-C score, KSS-F score, and knee range of motion significantly improved after surgery (P < 0.01) for all the patients. The postoperative KSS-C score in normal PTS group (88.76±2.79) was significantly higher than the KSS-C score in abnormal PTS group (84.42±3.35, P < 0.01), but no significant difference between the 2 groups was observed in postoperative KSS-F score and knee range of motion (P > 0.01). In addition, there was no correlation between the change of PTS and postoperative KSS-C score (r=-0.034, 95%CI: -0.247 to 0.186, P = 0.759), KSS-F score (r = -0.014, 95%CI: -0.238 to 0.198, P = 0.901) and knee range of motion (r= 0.045, 95%CI: -0.214 to 0.302, P = 0.686).@*CONCLUSION@#The posterior tibial slope between 3° and < 8° can be recommended to improve knee joint function in mobile UKA, and excessive or insufficient PTS should be avoided.

Effectiveness of medial open wedge high tibial osteotomy combined with posterior slope angle of tibial plateau correction in treatment of osteoarthritis of limited flexion knee with varus deformity / 中国修复重建外科杂志

Objective: To explore the short-term effectiveness of medial open wedge high tibial osteotomy (OWHTO) combined with posterior slope angle of tibial plateau correction to treat the osteoarthritis of limited flexion knee with varus deformity.

Relación entre la inclinación posterior de la tibia proximal y la inclinación meniscal. Estudio anatómico en resonancia magnética / The correlation between posterior tibial slope and meniscal slope. Anatomical study and magnetic resonance imaging

INTRODUCCIÓN: La geometría articular y las estructuras óseas se han mencionado como factores de riesgo para ruptura del ligamento cruzado anterior (LCA). La inclinación posterior de la tibia proximal (IPTP) es uno de los factores anatómicos mencionados. No se han encontrado estudios que reporten el rol del menisco externo en la estabilidad de la rodilla. El objetivo del siguiente estudio es determinar la relación entre la IPTP y la inclinación meniscal (IM) medidas por resonancia magnética (RM). MATERIAL Y MÉTODO: Se estudiaron 87 RM en 82 pacientes. Fueron excluidos pacientes con alteraciones anatómicas en la tibia proximal. Se realizaron las mediciones de la IPTP y la IM según el método de Hudeck. Se realizaron estudios de correlación para determinar la relación entre ambas variables. RESULTADOS: La edad media de los pacientes fue de 35.9 años. En el compartimento lateral la diferencia entre IPTP y la IM fue de 7.3° en promedio. El coeficiente Spearman entre IPTP del platillo externo y la IM es de 0.45. En el compartimento medial la diferencia entre la IPTP y la IM fue de 3.6°. El coeficiente Spearman entre la IPTP y la IM es de 0.57. CONCLUSIÓN: La correlación observada en ambos compartimentos es de baja a moderada lo que significa que la IPTP tiene poca participación en al valor final de la IM. Estos datos destacan la importancia del menisco externo en la biomecánica de la rodilla. Tipo de estudio: Serie de casos. Nivel de evidencia: IV.

BACKGROUND: Articular geometry and bony structures have been described as a risk factors for ACL ruptures. Posterior tibial slope´s one of the reported factors. We didn´t find studies describing the influence of the lateral meniscus in knee stability. Our aim is to determine the correlation between PTS and the meniscal slope (MS) in magnetic resonance images (MRI). METHODS: We studied 87 MRIs in 82 patients. Patients with anatomical changes in the proximal tibia (eg.: high tibial osteotomy) were discharged. The PTS and the MS was measured with the method of Hudeck. We did correlation tests to find any correlation between variables. RESULTS: Mean age was 35.9. In the lateral compartment the difference between PTS and MS was 7.3° and the Spearman tests was 0.45. In the medial compartment the difference between PTS and MS was 3.6° and the Spearmen tests was 0.57. CONCLUSIÓN: The correlation between both measures was low or moderate. The influence of the PTS in the MS it´s relative and we must consider the lateral meniscus in knee biomechanics. Type study: Number of cases. Level of evidence: IV.

The Effect of Hinge Direction on Posterior Tibial Slope in Medial Open-wedge High Tibial Osteotomy: A Study Based on Three-dimensional Computed Tomography Modelling / 中国运动医学杂志

Objective To explore factors affecting posterior tibial slope changes after the medial openwedge high tibial osteotomy.Methods The open-wedge high tibial osteotomy was simulated and performed on the three-dimensional proximal tibia model reconstructed based on the computed tomography (CT) scanning,and the roles of hinge axis direction and correction of genu varum in postoperative posterior tibial slope changes were analyzed separately.Results Hinge axis pointing anterolaterally was significantly associated with the increase of postoperative posterior tibial slope with regard to the axis along the anterior-posterior direction.Meanwhile,the correction of the genu varum at a larger angle was also a crucial factor for the increase of postoperative posterior tibial slopes.Conclusion Postoperative posterior tibial slope changes after open-wedge high tibial osteotomy is closely associated with the hinge axis direction and correcting angle of the genu varum.

Relationship between Mucoid Degeneration of the Anterior Cruciate Ligament and Posterior Tibial Slope in Patients with Total Knee Arthroplasty

PURPOSE: The purpose was to analyze the relationship between posterior tibial slope (PTS) and mucoid degeneration of the anterior cruciate ligament (ACL) in patients with total knee arthroplasty. MATERIALS AND METHODS: Four hundred and twenty-four patients (24 males and 400 females; 636 knees) who received total knee arthroplasty for osteoarthritis were included. Their mean age was 68.9 years (range, 48 to 88 years). The patients were classified into three groups according to the status of ACL; normal ACL group (group I), mucoid degeneration of ACL group (group II) and ruptured or absent ACL group (group III). Plain lateral radiographs were used to measure the PTS and the values were compared among groups. RESULTS: There were no significant differences with regard to gender, age and left-to-right side ratio among groups (p>0.05). The mean PTS was 9.9degrees (range, 0.6degrees to 20.1degrees) in group I (161 knees), 10.8degrees (range, 0.2degrees to 21.8degrees) in group II (342 knees) and 12.3degrees (range, 2degrees to 22.2degrees) in group III (133 knees), which showed significant differences (p<0.001). CONCLUSIONS: The patients with mucoid degeneration of the ACL and those with ruptured or absent ACL had greater PTS than those with normal ACL. These findings suggest that an increased PTS may be one of the causative factors for mucoid degeneration of the ACL.

Effect of Posterior Femoral Condylar Offset and Posterior Tibial Slope on Maximal Flexion Angle of the Knee in Posterior Cruciate Ligament Sacrificing Total Knee Arthroplasty

PURPOSE: To evaluate the effect of femoral condylar offset and posterior tibial slope on maximal flexion angle of the knee in posterior cruciate ligament (PCL)-sacrificing total knee arthroplasty (TKA, Medial-Pivot Knee System). MATERIALS AND METHODS: Forty-five knees in 35 patients who could be followed up more than 1 year after PCL-sacrificing TKA were evaluated retrospectively. We measured and analyzed the preoperative and postoperative maximal flexion angle, posterior femoral condylar offset difference, posterior femoral condylar offset ratio difference, and tibial slope. RESULTS: The mean maximal flexion angle after TKA was 118.44degrees+/-9.8degrees and significantly related to postoperative tibial slope (11.78degrees+/-6.2degrees) in correlation analysis (R=0.451, p=0.002). There was no statistical relationship between the postoperative maximal flexion angle and the posterior femoral condylar offset difference (3.24+/-3.862 mm, R=0.105, p=0.493) and posterior femoral condylar offset ratio difference (0.039+/-0.029 mm, R=-0.163, p=0.284). CONCLUSIONS: The maximal flexion angle of the knee after PCL-sacrificing TKA was significantly related to the postoperative tibial slope. Therefore, posterior tibial slope can be considered as a factor that affects maximal flexion angle after PCL-sacrificing TKA.

Clinical Results Associated with Changes of Posterior Tibial Slope in Total Knee Arthroplasty

PURPOSE: The purpose of this retrospective study is to investigate the effect of posterior tibial slope (PTS) on clinical results in total knee replacement arthroplasty (TKA).

The Correlation between Posterior Tibial Slope and Maximal Angle of Flexion after Total Knee Arthroplasty

PURPOSE: The purpose of this study was to evaluate the correlation between the posterior tibial slope and the maximal angle of flexion after total knee arthroplasty.

PS-TKA with more than 10degrees of Preoperative Posterior Tibial Slope

PURPOSE: We wanted to evaluate the effects of a preoperative posterior tibial slope of more than 10degrees on the extension gap and patellar height during posterior substituted total knee arthroplasty. MATERIALS AND METHODS: One hundred ten posterior substituted total knee arthroplasties were divided into group I (more than 10degrees of preoperative posterior tibial slope, n=56) and group II (less than 10degrees of slope, n=54). Each group was evaluated to compare the frequency of additional distal femoral resections due to an insufficient extension gap and the correlation with the decrease of the patellar bone height. RESULTS: In each group, the preoperative tibial slope was 12.77degrees (+/-3.22degrees) vs. 6.72degrees (+/-2.58degrees), respectively (p=0.000) and the decrease of the posterior slope was 10.74degrees (+/-3.54degrees) vs. 4.78degrees (+/-2.66degrees), respectively, (p=0.000). The frequencies of additional distal femoral resection were 54.5% vs. 46.1%, respectively, (p=0.448) with flexion contracture and 11.8% vs. 34.1%, respectively, (p=0.022) without flexion contracture. The decrease of the patellar bone height was 0.35 (+/-4.79) mm vs. 1.99 (+/-4.78) mm, respectively, (p=0.075). There was weak correlation between the decrease of the patellar bone height and the decrease of the posterior tibial slope (r=-0.253, p=0.016). CONCLUSION: In the group having more than 10degrees of preoperative posterior tibial slope without flexion contracture, the decrease of the posterior tibial slope had to be considered as one of the factors that affected making the extension gap significantly greater during the gap technique and to preserve the patellar bone height.

Medial Meniscal Tears in Anterior Cruciate Ligament-Deficient Knees: Effects of Posterior Tibial Slope on Medial Meniscal Tear

PURPOSE: To evaluate the incidence of meniscal tears in patients with chronic anterior cruciate ligament (ACL)-deficient knees, and to determine the influence of posterior tibial slope (PTS) on medial meniscal tears in ACL-deficient knees. MATERIALS AND METHODS: We reviewed 174 patients (174 knees) with a mean age of 30.7 years who underwent ACL reconstruction for chronic ACL tears. We divided the patients into two groups: low group (135 knees with a PTS or =13degrees). RESULTS: The incidence of medial meniscus tears was 44% (77/174), and that of lateral meniscus tears was 35% (61/174). The mean PTS in patients with medial meniscal tears was 11.4degrees+/-3.0degrees, whereas that in patients without medial meniscal tears was 9.8degrees+/-2.4degrees. The incidence of meniscal tears was 57.8% (78/135) in the low group and 89.7% (35/39) in the high group (p or =13degrees is a risk factor for secondary medial meniscal tears in ACL-deficient knees. So, we suggest that PTS is one of the considerations for determining early ACL reconstruction to prevent secondary meniscal tears.

Clinical Relevance of the Femoral Intercondylar Notch Width and the Posterior Tibial Slope for ACL Rupture

PURPOSE: The purpose of this study was to evaluate the relationship between the femoral intercondylar notch width (ICW), the posterior tibial slope angle (PTS), rupture of the anterior cruciate ligament (ACL) and the ruptured site. MATERIALS AND METHODS: We retrospectively reviewed 105 cases of ruptured ACL (105 patients), and 91 cases of intact ACL (91 patients). The ICW and PTS were measured from the plain knee radiographs. The ratio of the ICW and the femoral intercondylar notch height (ICH) was also measured. As for the site of ACL rupture, the patients with a ruptured ACL were divided into 3 groups (group 1: femoral attach site, 2: mid-substance, 3: tibial attach site), and the correlations between the ICW and the PTS of each group were analyzed. RESULTS: The mean ICW of the ACL ruptured group was 15.51+/-4.30 mm (95% confidence interval: 15.48~15.53), that of the ACL intact group was 24.49+/-3.86 mm (24.47~24.52), and the mean PTS of the ruptured ACL group was 7.68+/-3.78degrees (7.65~7.70) and that of the intact ACL group was 6.12+/-3.85degrees (6.10~6.13). A narrow ICW was a significant risk factors for ACL rupture (odds ratio=0.661 [0.602~0.720], p<0.01). But we did not get any statistically significant results for the increase PTS (odds ratio=1.073 [1.062~1.134], p=0.197). According to the ruptured site, the analysis of variance of the ICW and PTS had no significant correlation. CONCLUSION: A narrow ICW is a significant risk factor for ACL rupture.

The Change of the Posterior Tibial Slope after Cruciate Retaining Total Knee Arthroplasty / 대한정형외과학회잡지

PURPOSE: To analyze the pre- and postoperative posterior tibial slope angle (PSA) of performing cruciate-retaining total knee arthroplasty (TKA) and to identify the ideal value of the PSA in relation to the clinical results. MATERIALS AND METHODS: From June 1999 to May 2005, 202 TKA with a NexGen(R) cruciate-retaining knee were performed in 160 patients. The mean follow-up period was 39.8 months. The pre- and postoperative PSA referenced by the proximal tibial medullary canal (PSA-A) and the proximal tibial anterior cortex (PSA-B) were measured by two independent observers. The knee and function scoring system of the American Knee Society and the range of motion of the knee at the last follow-up were evaluated as the clinical results. RESULTS: The mean PSA-A was 11.4+/-4.8degrees preoperatively and 6.0+/-2.8degrees postoperatively, and the mean PSA-B was 13.6+/-4.9degrees preoperatively and 8.1+/-2.9degrees postoperatively. The difference between the pre- and postoperative PSA increased as the preoperative PSA-A changed from 6.0degrees and the PSA-B changed from 8.1degrees; these findings showed statistical significance based on a simple linear regression (PSA-A: r= 0.837, p=0.000; PSA-B: r=0.834, p=0.000). The knee and function score of American Knee Society improved respectively from 62.9 and 55.8, preoperatively, to 97.4 and 89.7 respectively, at the last follow-up. The range of motion of the knee joint was 128.0degrees preoperatively and 129.7degrees at the last follow-up. CONCLUSION: In cruciate retaining total knee arthroplasty, PSA-A is mostly distributed within 3.2-8.8degrees, and a reasonable range of PSA-A is 6.0+/-2.8degrees.

Influence of Posterior Tibial Slope on Stability after Total Knee Arthroplasty

PURPOSE: The purpose of this study was to compare the influence of posterior tibial slope on hyperextension deformities and anterior tibial translation between two types of total knee arthroplasty(TKA); posterior cruciate retaining(CR) and substituting(PS), which have different polyethylene conformity. MATERIALS AND METHODS: 109 consecutive primary TKAs using Nexgen(R)(Zimmer, Warsaw, IN) CR(n=60) and PS (n=49) type prostheses, performed from July 1995 to August 2005 were reviewed. Each group of CR and PS were divided into two categories according to the degree of posterior tibial slope; 0~5 degrees and more than 5 degrees. The amount of hyperextension deformities and anterior tibial translation measured at the immediate and postoperative 2 years radiographs were analyzed in each subdivided groups. RESULTS: The significant amount of hyperextension deformities(p<0.05) and anterior tibial translation(p<0.05) were noted in the CR group. The CR group with more than 5 degrees of posterior tibial slope was more prone to develop the hype- rextension deformities(p=0.003) and anterior tibial translation(p=0.007) compared with the group that has posterior tibial slope less than 5 degrees. But in the PS group, there was no significant difference related with hyperextension deformities (p =0.240) and anterior tibial translation(p=0.204) between the two groups. CONCLUSION: The posterior tibial slope more than 5 degrees resulted in increments of the hyperextension and anterior tibial translation in the CR TKA group than in the PS TKA group.