Background: There is a paucity of clinical information to guide the treatment of a combined anterior cruciate ligament (ACL) tear and Segond fracture., Purpose: To compare clinical outcomes, graft failure rates, and activity levels between patients undergoing ACL reconstruction (ACLR) with and without an untreated Segond fracture at a minimum 2-year follow-up., Study Design: Cohort study; Level of evidence, 3., Methods: This study included a group of patients with a combined ACL tear/untreated Segond fracture that was matched based on age, sex, body mass index, and graft type to a control group of patients with an ACL tear and no Segond fracture. All patients were treated with ACLR alone between the years of 2000 and 2015. The diagnosis of a Segond fracture, or bony avulsion of the anterolateral complex, was made by radiographic analysis. Data regarding the initial injury, surgical intervention, and physical examination findings were recorded. Clinical and functional outcomes were obtained using physical examination results, International Knee Documentation Committee (IKDC) subjective scores, and Tegner activity levels., Results: Twenty patients (16 male, 4 female) with a combined ACL tear/untreated Segond fracture with a mean age of 26.3 years (range, 13-44 years) were matched to a control group of 40 patients (32 male, 8 female) with an ACL tear and no Segond fracture with a mean age of 26.4 years (range, 13-47 years). The study group was followed for a mean of 59.1 months (range, 24-180 months) and the control group for a mean of 55.5 months (range, 24-120 months). The mean IKDC score was 86.5 (range, 54-100) for the study group compared with 93.0 (range, 54-100) for the control group ( P = .03). The graft rupture rate was 10% for both groups ( P = .97). The mean time to rupture was 33.0 months (range, 21-45 months) in the study group and 63.5 months (range, 39-88 months) in the control group ( P = .24). Patients in the study group had significantly more anteroposterior instability by preoperative Lachman testing than those in the control group (control group: 0 normal, 3 grade 1+, 37 grade 2+, 0 grade 3+; study group: 0 normal, 1 grade 1+, 10 grade 2+, 9 grade 3+; P = .0001). There was no significant difference between the 2 groups in regard to postoperative Lachman testing (control group: 35 normal, 3 grade 1+, 2 grade 2+, 0 grade 3+; study group: 17 normal, 3 grade 1+, 0 grade 2+, 0 grade 3+; P = .31). Patients in the study group had significantly more instability by preoperative pivot-shift testing than those in the control group (control group: 0 normal, 7 grade 1+, 33 grade 2+, 0 grade 3+; study group: 1 normal, 1 grade 1+, 11 grade 2+, 7 grade 3+; P = .0003). No significant difference was found between the 2 groups for postoperative pivot-shift testing (control group: 36 normal, 2 grade 1+, 2 grade 2+, 0 grade 3+; study group: 18 normal, 1 grade 1+, 1 grade 2+, 0 grade 3+; P = .61) or final Tegner activity level (median, 6)., Conclusion: At midterm follow-up, patients undergoing ACLR with and without a Segond fracture had similar pivot-shift test results, graft failure rates, and activity levels. The IKDC score was statistically worse in the patients with a combined ACL tear/untreated Segond fracture, but the difference was less than the minimal clinically important difference for the IKDC score. These findings suggest that patients with a combined ACL tear/untreated Segond fracture can have comparable outcomes to patients with an ACL tear and no Segond fracture when treated with ACLR alone.