Finite Element Analysis of Two Methods of ACL Reconstruction under Different Posterior Tibial Slope

Aims and Objectives: In recent publications on acl-ruptures and especially on failure of acl reconstruction there comes a strong focus on posterior tibial slope (PTS). ACL reconstructions with a PTS of >12° have an 8 times higher risk of recurrent instability and reconstruction failure. But many questions stay unclear so far-When do we have to correct the tibial slope? How do we correct it? What about simultaneous frontal axis deviations? In this publication a new algorhythm is presented. Materials and Methods: The following aspects have to be evaluated Is the PTS the only dimension of the deformity or do we have to correct the frontal axis simultaneuosly? Performing a anterior closed wedge extension osteotomy: when do we go distal the tuberosity and when do we perform a tuberosity osteotomy and use it as “bio plating”? Osteosynthesis only screws or always plate? Are there indications for a contineous correction, f.e. with a hexapod? Whats the role of preoperative range of motion of the knee (especially extension)? Always tunnel filling in the same surgery? What about PCL insufficiency and low PTS? Results: An algorhythm is presented giving a treatment path for the different questions mentioned. The procedures are shown step by step in clinical examples and surgery documentation for every pathway. Conclusion: Posterior tibial slope plays an critical role in ACl recontruction. In primary ACl tear a slope correction is probably not indicated. In ACL reconstruction failure a analysis of the PTS needs to be done and correction needs to be discussed. Simultaneuous varus deormities need to be corrected by openwedge valgisation - extension high tibial osteotomy (HTO), while as isolated PTS elevation is subject to an anterior closed wedge extension HTO. Preoperative range of motion needs to be respected not to create hyperextension. Osteosynthesis can be perormed with only screws using the tibial tubercle as “bio-plating”. In cases of former bone-tendeon-bone (BTB) ACL reconstruction a tibial tubercle osteotomy should be avoided and a infratuberositeal osteotomy should be performed and stabilized with plate osteosynthesis. In severe postraumatic cases contineous correction of the slope with fixateur externe, f.e. hexapodes, needs to be performed.

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Steep Posterior Tibial Slope, Anterior Tibial Subluxation, Deep Posterior Lateral Femoral Condyle, and Meniscal Deficiency Are Common Findings in Multiple Anterior Cruciate Ligament Failures: An MRI Case-Control Study

The American Journal of Sports Medicine ◽

10.1177/0363546518823544 ◽

2019 ◽

Vol 47 (2) ◽

pp. 285-295 ◽

Cited By ~ 20

Author(s):

Alberto Grassi ◽

Luca Macchiarola ◽

Francisco Urrizola Barrientos ◽

Juan Pablo Zicaro ◽

Matias Costa Paz ◽

...

Keyword(s):

Acl Reconstruction ◽

Tibial Plateau ◽

Femoral Condyle ◽

Tibial Slope ◽

Lateral Femoral Condyle ◽

Posterior Tibial Slope ◽

Control Group ◽

Medial Tibial Plateau ◽

Posterior Tibial ◽

Anterior Tibial

Background: Tibiofemoral anatomic parameters, such as tibial slope, femoral condyle shape, and anterior tibial subluxation, have been suggested to increase the risk of anterior cruciate ligament (ACL) reconstruction failure. However, such features have never been assessed among patients experiencing multiple failures of ACL reconstruction. Purpose: To compare the knee anatomic features of patients experiencing a single failure of ACL reconstruction with those experiencing multiple failures or with intact ACL reconstruction. Study: Case-control study; Level of evidence, 3. Methods: Twenty-six patients who experienced failure of revision ACL reconstruction were included in the multiple-failure group. These patients were matched to a group of 25 patients with failure of primary ACL reconstruction and to a control group of 40 patients who underwent primary ACL reconstruction with no failure at a minimum follow-up of 24 months. On magnetic resonance imaging (MRI), the following parameters were evaluated: ratio between the height and depth of the lateral and medial femoral condyles, the lateral and medial tibial plateau slopes, and anterior subluxation of the lateral and medial tibial plateaus with respect to the femoral condyle. The presence of a meniscal lesion during each procedure was evaluated as well. Anatomic, demographic, and surgical characteristics were compared among the 3 groups. Results: The patients in the multiple-failure group had significantly higher values of lateral tibial plateau slope ( P < .001), medial tibial plateau slope ( P < .001), lateral tibial plateau subluxation ( P < .001), medial tibial plateau subluxation ( P < .001), and lateral femoral condyle height/depth ratio ( P = .038) as compared with the control group and the failed ACL reconstruction group. Moreover, a significant direct correlation was found between posterior tibial slope and anterior tibial subluxation for the lateral ( r = 0.325, P = .017) and medial ( r = 0.421, P < .001) compartments. An increased anterior tibial subluxation of 2 to 3 mm was present in patients with a meniscal defect at the time of the MRI as compared with patients who had an intact meniscus for both the lateral and the medial compartments. Conclusion: A steep posterior tibial slope and an increased depth of the lateral femoral condyle represent a common finding among patients who experience multiple ACL failures. Moreover, higher values of anterior subluxation were found among patients with repeated failure and those with a medial or lateral meniscal defect.

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Increased Radiographic Posterior Tibial Slope Is Associated With Subsequent Injury Following Revision Anterior Cruciate Ligament Reconstruction

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967119879373 ◽

2019 ◽

Vol 7 (11) ◽

pp. 232596711987937 ◽

Cited By ~ 7

Author(s):

Richard J. Napier ◽

Enrique Garcia ◽

Brian M. Devitt ◽

Julian A. Feller ◽

Kate E. Webster

Keyword(s):

Risk Factor ◽

Acl Reconstruction ◽

Cruciate Ligament ◽

Acl Injury ◽

Tibial Slope ◽

Posterior Tibial Slope ◽

Posterior Tibial ◽

Revision Acl Reconstruction ◽

Injury Group ◽

Anterior Cruciate

Background: Increased posterior tibial slope has been identified as a possible risk factor for injury to the anterior cruciate ligament (ACL) and has also been shown to be associated with ACL reconstruction graft failure. It is currently unknown whether increased posterior tibial slope is an additional risk factor for further injury in the context of revision ACL reconstruction. Purpose: To determine the relationship between posterior tibial slope and further ACL injury in patients who have already undergone revision ACL reconstruction. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 330 eligible patients who had undergone revision ACL reconstruction between January 2007 and December 2015 were identified from a clinical database. The slope of the medial and lateral tibial plateaus was measured on perioperative lateral radiographs by 2 fellowship-trained orthopaedic surgeons using a digital software application. The number of subsequent ACL injuries (graft rupture or a contralateral injury to the native ACL) was determined at a minimum follow-up of 2 years (range, 2-8 years). Tibial slope measurements were compared between patients who sustained further ACL injury to either knee and those who did not. Results: There were 50 patients who sustained a third ACL injury: 24 of these injuries were to the knee that underwent revision ACL reconstruction, and 26 were to the contralateral knee. Medial and lateral slope values were significantly greater for the third-injury group compared with the no–third injury group (medial, 7.5° vs 6.3° [ P = .01]; lateral, 13.6° vs 11.9° [ P = .001]). Conclusion: Increased posterior tibial slope, as measured from lateral knee radiographs, was associated with increased risk of graft rupture and contralateral ACL injury after revision ACL reconstruction. This is consistent with the concept that increased posterior slope, particularly of the lateral tibial plateau, is an important risk factor for recurrent ACL injury.

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