PurposeThis study aimed to evaluate short-term outcomes at least 2 years after dome-shaped high tibial osteotomy (HTO) combined with all-inside anterior cruciate ligament reconstruction (ACL) in patients with persistent ACL insufficiency accompanied by pain due to varus deformity.MethodsThe study enrolled 19 knees of 18 patients. The mean age was 58.4 ± 13.4 years and the mean postoperative follow-up period was 31.4 ± 6.6 months (24–49 months). JOA(Japanese Orthopaedic Association)-OA(osteoarthritis) score, Lysholm score, radiographic outcomes such as femoro-tibia angle (FTA) in a standing position, side-to-side difference in KT-1000 measurements were evaluated at pre op. and post operative final follow up. And arthroscopic evaluation was evaluated at the time of the HTO plate-removal procedure.ResultsBefore surgery, the mean JOA-OA score was 65.0 ± 13.5, the mean Lysholm score was 47.2 ± 16.2, the mean femoro-tibia angle (FTA) in a standing position was 183.8 ± 3.4° (range;180–190°), and the mean side-to-side difference in KT-1000 measurements was 4.1 ± 1.3 mm. After surgery, the mean JOA-OA score, Lysholm score, and side-to-side difference in KT-1000 measurements improved to 93.1 ± 6.0 (P< 0.00001), 94.2 ± 5.9 (P< 0.00001), and -0.2 ± 0.8 mm (P< 0.00001), respectively. The mean FTA decreased to 168.0 ± 3.3 (P< 0.00001), and the mean posterior tibial slope angle decreased to 5.0 ± 3.6° from 6.9 ± 2.6° preoperatively (P= 0.024). Arthroscopic evaluation during the HTO plate-removal procedure of 17 knees were performed at a mean of 16 months after the surgery. The reconstructed ACL graft in 13 knees were successful, a cyclops lesion in one knee, and looseness of the graft in three knees.ConclusionsDome-shaped HTO allows for a relatively high degree of varus correction and decreases the steep posterior tibial slope that causes excessive load on the ACL. Therefore, its use in combination with ACL reconstruction seems to be effective.