Chronicity of Anterior Cruciate Ligament Deficiency, Part 1: Effects on the Tibiofemoral Relationship Before and Immediately After Anatomic ACL Reconstruction With Autologous Hamstring Grafts

Abstract

Background:It remains unclear whether the tibiofemoral relationship in the sagittal plane is restored after anatomic anterior cruciate ligament (ACL) reconstruction, particularly in cases of chronic ACL deficiency (ACLD).Hypothesis:Patients with long-term ACLD will exhibit an anteriorly subluxed tibia both preoperatively and immediately postoperatively, even after anatomic reconstruction.Study Design:Cohort study; Level of evidence, 2.Methods:In total, 358 patients who had undergone anatomic ACL reconstruction with autologous semitendinosus grafts were divided into 5 groups based on chronicity of ACLD: (1) 0 to 6 months, (2) 6 months to 1 year, (3) 1 to 2 years, (4) 2 to 5 years, and (5) longer than 5 years. Preoperatively and immediately postoperatively, all patients underwent lateral radiography in extension to evaluate the tibiofemoral relationship, specifically with regard to anterior tibial subluxation (ATS), space for the ACL (sACL), and extension angle. Demographic and radiographic factors were compared among the 5 groups.Results:Preoperative ATS values in groups 4 (mean ± SD, 2.9 ± 2.1 mm) and 5 (2.6 ± 1.9 mm) were significantly greater than in group 1 (1.6 ± 1.9 mm). Postoperatively, the tibia was posteriorly overconstrained in all groups, and there was no difference in immediately postoperative ATS among the 5 groups. Further evaluation of the tibiofemoral relationship in the sagittal plane revealed that the mean preoperative side-to-side difference in sACL (sACL-SSD) was greater in groups 4 (2.5 ± 1.6 mm) and 5 (2.2 ± 1.7 mm) than in group 1 (1.2 ± 1.5 mm). Immediately after ACL reconstruction, however, there were no group-dependent differences in sACL-SSD. No significant group-dependent differences were found for extension deficit.Conclusion:Chronicity of ACLD had an effect on the preoperative tibiofemoral relationship in the sagittal plane, including ATS and sACL-SSD, especially in patients with ACLD longer than 2 years. However, preoperative extension deficit was not influenced by chronicity. Immediately postoperatively, chronicity did not affect the ability of anatomic ACL reconstruction to reduce subluxation.

Chronicity of Anterior Cruciate Ligament Deficiency, Part 2: Radiographic Predictors of Early Graft Failure

“…Of these, 358 patients were included in this study (147 men, 211 women; mean ± SD age, 25.7 ± 11.6 years) ( Table 1), according to inclusion and exclusion criteria described in part 1. 39 These 358 patients were divided into 5 groups based on the chronicity of their ACLD: 0-6 months (group 1; n ¼ 228), 6 months to 1 year (group 2; n ¼ 27), 1 to 2 years (group 3; n ¼ 27), 2 to 5 years (group 4; n ¼ 31), and longer than 5 years (group 5; n ¼ 45).…”

“…Part 1 of the present study also revealed that although patients with longer periods of ACL deficiency had increased ATS, anatomic ACL reconstruction could restore the tibiofemoral relationship regardless of chronicity. 39 However, we have noted that in some clinical cases, even if the tibia is posteriorly overreduced immediately after anatomic ACL reconstruction, long-term ACLD seems to be accompanied by early ACL graft failure without any trauma, as seen on MRI at several months after surgery. Generally, reasons for graft failure include trauma, technical error, and poor biological healing of the graft.…”

“…Part 1 of the present study also revealed that although patients with longer periods of ACL deficiency had increased ATS, anatomic ACL reconstruction could restore the tibiofemoral relationship regardless of chronicity. 39…”

“…Part 1 of this study revealed that side-to-side difference in sACL (sACL-SSD) correlated moderately with ATS ( r = 0.406) and could be a convenient parameter for evaluation of ATS. 39…”

“…Part 1 of this study revealed that side-toside difference in sACL (sACL-SSD) correlated moderately with ATS (r ¼ 0.406) and could be a convenient parameter for evaluation of ATS. 39 The first aim of part 2 of the study was to clarify differences in the incidence of early ACL graft failure at 6 months, as evident on MRI, according to chronicity of ACLD. Subsequently, we identified the population with a high rate of early graft failure and analyzed these patients further to determine predisposing factors.…”