Traumatic Separation of a Bipartite Patella With Concurrent Quadriceps Tendon and Retinacular Injury: A Report of a Rare Case.

Bipartite patella is a developmental variant that typically remains unrecognized but may rarely comprise an incidental finding following trauma. Traumatic separation of a bipartite patella is a rare clinical entity that can mimic a patellar fracture. The concurrent presence of complete quadriceps tendon rupture and retinacular injury is extremely uncommon. We describe the case of a 61-year-old male who presented after a ground-level fall with anterior knee pain, palpable suprapatellar gap, joint effusion, and inability to actively extend the knee. Radiographs revealed separation of the patella with smooth fragment margins, suggestive of a bipartite patella rather than a true fracture. No supplementary imaging was performed. Intraoperative findings confirmed the diagnosis of bipartite patella with accompanying complete quadriceps tendon rupture and bilateral retinacular disruption. Surgical management involved the preservation and fixation of the patellar fragment with a compression screw, combined with restoration of the extensor mechanism employing quadriceps tendon repair with bony anchors. Postoperative follow-up demonstrated a stable fragment position and favourable functional outcomes with restoration of knee stability and near-complete range of motion. This case highlights screw fixation of the patellar fragment as a viable therapeutic strategy in the setting of bipartite patella separation with concurrent complete quadriceps tendon rupture. By demonstrating a successful outcome with this rarely used treatment modality, this case expands the limited knowledge base available to guide clinicians in managing similar cases.