Background <p>The popliteomeniscal fascicles (PMFs) connect the lateral meniscus to the popliteal hiatus and provide stability to the lateral meniscus. A high percentage of knees with acute and chronic anterior cruciate ligament (ACL), posterolateral corner injuries and/or hypermobile lateral meniscus (HLM) have concurrent damage to the PMFs. The present study evaluated the outcome of a two-year follow-up of an all-inside arthroscopic procedure to manage tears of the PMFs associated with lateral meniscus instability.</p> Methods <p>A total of 11 patients with a tear of the PMFs diagnosed clinically and at MRI underwent an all-inside arthroscopic repair. Patients were enrolled prospectively and evaluated using the Tegner, Lysholm, and IKDC scales for two years.</p> Main findings <p>The post-operative MRI revealed that the PMFs had been successfully repaired arthroscopically. According to the subjective IKDC score (<i>p</i> &lt; 0.05), the Lysholm score (<i>p</i> &lt; 0.001), and the Tegner activity scale (<i>p</i> &lt; 0.001), comparing pre-operative and post-operative values, all patients showed significant improvement at the two-year follow-up.</p> Principal conclusions <p>Tears of the PMFs predispose the lateral compartment of the knee to chondral lesion, lateral meniscus instability, and progression of osteoarthritis. This study represents the largest series of all-inside repair techniques for PMF disruption. At two-year follow-up, all patients had improved clinically, without any giving way sensation during rotational movements. Most of them had returned to their pre-injury level of activity.</p>