Tibial slope and medial meniscectomy significantly influence short-term knee laxity following ACL reconstruction

Abstract

PurposeTo determine demographic, anatomic, and surgical factors associated with static and dynamic Anterior Tibial Translation (ATT) following ACL reconstruction. The hypothesis was that both static and dynamic ATT would be greater in knees with high tibial slope or that required meniscectomy. MethodsThe authors prospectively enrolled 280 consecutive patients that had primary ACL reconstruction using hamstring autografts at one center for which preoperative tear type, meniscal tears, and medial tibial slope were documented. A total of 137 were excluded due to concomitant extra‐articular tenodesis or surgical antecedents on either knee, and 18 were lost to follow‐up, leaving 125 that were evaluated at a minimum of 6 months including: static ATT on monopodal weight‐bearing radiographs, and dynamic ATT on differential stress radiographs using the Telos™ device. ResultsBoth postoperative static and dynamic ATT were strongly associated with preoperative static and dynamic ATT (respectively, β = 0.068 and β = 0.50, p < 0.001). Multivariable regression confirmed that postoperative static ATT increased with tibial slope (β = 0.24; CI 0.01–0.47; p = 0.042) and in knees that had partial medial meniscectomy (β = 2.05; CI 0.25–3.84; p = 0.025), while dynamic ATT decreased with age (β = − 0.11; CI − 0.16 to − 0.05; p < 0.001), and increased with tibial slope (β = 0.27; CI 0.04–0.49; p = 0.019) and in knees that had partial medial meniscectomy (β = 2.20; CI 0.35–4.05; p = 0.019). ConclusionBoth static and dynamic ATT following ACL reconstruction increased with tibial slope and in knees that had partial medial meniscectomy. These findings could help surgeons tailor their techniques and ‘à la carte’ rehabilitation protocols, by preserving the menisci and sometimes delaying full weight‐bearing and return to sport in patients at risk, and hence improve outcomes and prevent graft failures. Study designCohort study. Level of evidenceV.

Slope-Reducing Tibial Osteotomy Combined With Primary Anterior Cruciate Ligament Reconstruction Produces Improved Knee Stability in Patients With Steep Posterior Tibial Slope, Excessive Anterior Tibial Subluxation in Extension, and Chronic Meniscal Posterior Horn Tears

“…7,9,30 There is growing evidence that steep posterior tibial slope (PTS) has a negative effect on knee stability after ACLR. 5,9,10,33 Steep PTS produces an anteriorly directed shear force when a compressive load is applied to the knee joint, resulting in excessive anterior tibial subluxation (ATS) in extension. 15 Grassi et al 13 investigated the tibiofemoral anatomic parameters in patients with ACLR failure and found that steep PTS (>13°) and excessive ATS in extension (>10 mm) were common findings (Figure 1).…”

“…22 Furthermore, several studies have evaluated the association between steep PTS and the increased risk of concomitant MPHTs in ACL-deficient knees, highlighting the potential risk of ACLR failure if the concomitant MPHTs are not well addressed. 8,9,23…”

Excessive Preoperative Anterior Tibial Subluxation in Extension Is Associated With Inferior Knee Stability After Anatomic Anterior Cruciate Ligament Reconstruction

“…2,10 These observations raised concerns regarding clinical outcomes after ACLR, as the altered tibial position can negatively affect the restoration of normal knee kinematics and the improvement of postoperative knee stability. 6,8,11,16,17…”

“…2,10 These observations raised concerns regarding clinical outcomes after ACLR, as the altered tibial position can negatively affect the restoration of normal knee kinematics and the improvement of postoperative knee stability. 6,8,11,16,17 The risk factors of ATS in extension after ACL injury have been the focus of several recent reports. 24,27 Increases in ATS in extension have been observed in the setting of combined posterior horn of medial and lateral meniscal tears.…”

Sequential analysis of three-dimensional tibiofemoral relationship through anatomic anterior cruciate ligament reconstruction with gravity-assisted radiographic technique in prone position

“…Thus, the effect of weight/size of calves would be small in this study. Fifth, it might be better to exclude meniscal tears because the anterior tibial displacement was larger after medial meniscectomy in the ACL-deficient/ACL-reconstructed knees 32 , 37 , 40 . All the meniscal tears underwent meniscal repair except one with partial lateral meniscectomy for an incomplete radial tear.…”