Background: There are limited data comparing the outcomes of similarly matched patients with a medial meniscus posterior root tear (MMPRT) treated with nonoperative management, partial meniscectomy, or repair. Purpose/Hypothesis: The purpose was to compare treatment failure, clinical outcome scores, and radiographic findings for a matched cohort of patients who underwent either nonoperative management, partial meniscectomy, or transtibial pull-through repair for an MMPRT. We hypothesized that patients who underwent meniscus root repair will have lower rates of progression to arthroplasty than patients who were treated with nonoperative management or partial meniscectomy. Study Design: Cohort study; Level of evidence, 3. Methods: Patients who underwent transtibial medial meniscus posterior horn root repair were matched by meniscal laterality, age, sex, and Kellgren-Lawrence (K-L) grades to patients treated nonoperatively or with a partial meniscectomy. Progression to arthroplasty rates, International Knee Documentation Committee and Tegner scores, and radiographic outcomes were analyzed between groups. Results: Forty-five patients were included in this study (15 nonoperative, 15 partial meniscectomy, 15 root repair). Progression to arthroplasty demonstrated significant differences among treatment groups at a mean of 74 months (nonoperative, 4/15; partial meniscectomy, 9/15; meniscal repair, 0/15; P = .0003). The meniscus root repair group had significantly less arthritic progression, as measured by change in K-L grade from pre- to postoperatively (nonoperative, 1.0; partial meniscectomy, 1.1; meniscal repair, 0.1; P = .001). Conclusion: Meniscus root repair leads to significantly less arthritis progression and subsequent knee arthroplasty compared with nonoperative management and partial meniscectomy in a matched cohort based on patient characteristics.