A review of patients with anterior cruciate ligament (ACL) insufficiency, symptomatic medial compartment osteoarthritis, and varus malalignment of the knee was performed. Twenty-six patients met the inclusion criteria. Twelve patients were treated with a valgus closing-wedge high tibial osteotomy (group 1). Fourteen patients were treated with a valgus closing-wedge high tibial osteotomy combined with arthroscopic ACL reconstruction (group 2). Twenty-five patients were available for follow-up at a minimum of 2 years. For group 1 patients, high tibial osteotomy alone had no effect on the Lachman test or pivot shift phenomena. For group 2 patients, combined high tibial osteotomy/ACL reconstruction resulted in a grade 1 Lachman test in 11 of 13 patients, and a negative pivot shift in 12 of 13 patients. No deficits in range of motion were noted in either group. Prior to surgery, 14 (56%) patients participated in recreational sports; 23 (92%) patients were able to participate in recreational sports at follow-up. Radiographs demonstrated osteoarthritic progression in group 1 and 2 patients (P<.05). The results of this study suggest that high tibial osteotomy alone and combined high tibial osteotomy/ACL reconstructions are effective in the surgical treatment of varus, ACL-deficient knees with symptomatic medial compartment arthritis; however, good or excellent results were more often seen after the combined procedure.