ObjectivesThe purpose of our study was to compare (1) posterior cruciate ligament (PCL) laxity, (2) patient-reported outcome, and (3) complications after the all-inside PCL reconstruction (Al-PCLR) technique and conventional PCLR (CON-PCLR) technique at minimum 2-year follow-up. We hypothesized that AI-PCLR and CONV-PCLR would yield similar results in PCL laxity, patient-reported outcomes, and complications. MethodA retrospective cohort study was conducted on patients who underwent PCLR with the Al-PCLR technique and CON-PCLR technique from 2012 to 2023 in a single hospital. Medical records were reviewed for patients’ demographic data, the technique of PCL reconstruction and complications. Patient-reported outcome scores, including International Knee Documentation Committee (IKDC), Tegner activity scale, and Lysholm score, as well as bilateral kneeling radiographs and physical examinations, were collected at least 2 years postoperatively. ResultsIncluded in the study were 24 patients: 11 who underwent the CON-PCLR technique (mean age 40.7 +years) and 13 who underwent Al-PCLR (mean age 34.3 + 12.9 years). Three patients in AI-PCLR group were lost to follow-up and one patient is the CON-PCLR group, a revision case, was excluded from the study.Bilateral stress kneeling radiographs showed a similar side-to-side difference between two groups (CON-PCLR vs AL-PCLR: mean 7.5 ± 5.2 vs 5.8 ± 4.8 mm; P = 0.38) There were no statically significant differences between the two groups in postoperative IKDC (CON-PCLR vs AL-PCLR: 68.9 vs 73.9; P = 0.37), Lysholm (89.1 vs 94.1; P = 0.42), or Tegner activity (6 vs 6.4; P = 0.68) scores. ConclusionAll-inside PCLR demonstrates comparable stability to Conventional PCLR, with satisfactory patient-report outcome at minimum 2 years follow up and low rate of complications in patients with multiligament knee injury.Level of evidence: III Retrospective comparative study.