A 50 yo male with no past medical history presents after falling from standing height.  He states he tripped and landed on his knee.  He has pain with any movement and there is palpable deformity of the knee.  He is unable to extend knee on exam.  An x-ray is shown.  What's the diagnosis?  Scroll down for answer.

Answer:

Patellar fracture

• mechanism
• direct force (fall, dashboard injury)
• indirect force (rapid knee flexion during contraction of quadriceps)
• management
• Assess for other traumatic injuries
• check for neurovascular compromise (distal pulses, sensation and motor function)
• if there is  >4mm of fracture gap and/or disruption (weakness) of extensor mechanism will need orthopedic consultation
• <4mm gap and intact extensor mechanism gets immobilizer and oupatient orthopedic referral

Luo TD, Marino DV, Pilson H. Patella Fractures. [Updated 2020 Aug 8]. In: StatPearls [Internet].Treasure Island (FL): StatPearls Publishing; 2020 Jan-.Available from:https://www.ncbi.nlm.nih.gov/books/NBK513330/