Total ruptures of the extensor apparatus of the knee

ABSTRACT OBJECTIVE: This was a retrospective case-control study on total ruptures of the extensor apparatus of the knee, aimed to compare patella fractures with tendinous ruptures. METHODS: The sample included 190 patients and 198 total ruptures of the knee extensor apparatus. All patients were evaluated by the same examiner after a minimum one-year follow-up. RESULTS: Tendinous ruptures occurred most frequently in men, in younger patients, and had better clinical and functional outcomes when compared with patella fractures; however, the former presented higher levels of thigh atrophy. Patella fractures occurred most frequently in women and in older patients and caused most frequently caused residual pain, muscle weakness, and limitations in daily activities. Comminuted fractures were related to high-energy trauma, lower clinical and functional outcomes, and higher levels of residual pain and osteosynthesis failure. Early removal of osteosynthesis material was related to better outcomes. Regarding the tendinous ruptures, over half of the patients presented risk conditions for tendinous degeneration; a longer delay until surgery was related to lower Kujala scores. CONCLUSION: The surgical repair of bilateral ruptures of the knee extensor apparatus resulted in satisfactory clinical and functional outcomes, which were better for tendinous ruptures when compared with patella fractures. However, these lesions are associated with non-negligible levels of residual pain, muscle weakness, atrophy, and other complications.