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Introduction Multiligament knee injuries (MLKIs) are severe injuries often leading to long-term functional limitations. Evidence on objective muscle strength and recovery after MLKI surgery is limited. This study investigated long-term hamstring and quadriceps strength and functional recovery following MLKI surgery and comparing single cruciate and bicruciate injuries.Materials and Methods Patients surgically treated for MLKI at a Level 1 trauma center between 2013–2020 were included. Isokinetic hamstring and quadriceps strength were assessed with a Biodex dynamometer. Functional performance was assessed with single-leg, triple, crossover, and 6-meter timed hop tests. Limb symmetry index (LSI) was calculated.Results Of 124 eligible patients, 90 (72%) participated (59% male; median age 49 years; mean follow-up 7±2.1 years). In total, 54% of the patients had not regained full quadriceps strength (LSI <90%), and 40% had persistent hamstring deficits. Strength was significantly lower in the injured limb for quadriceps and hamstrings (p=0.01). Mean quadriceps LSI for PeakTorque BodyWeight was 88% at 60°/sec and 90% at 240°/sec; hamstring LSI was higher with 93% and 97%, respectively. Mean hop test LSIs ranged from 93% (single-leg) to 99% (crossover), though 42% did not reach 90% LSI for the single-leg. Patients with bicruciate injuries had significantly lower quadriceps strength and 6-meter timed hop performance compared with single cruciate injuries (p<0.05).Conclusion Long-term deficits in quadriceps and hamstring strength are common even 7 years after MLKI surgery, with many patients failing to regain full functional symmetry. Bicruciate injuries are associated with more pronounced strength and functional impairments than single cruciate injuries.