Patellar tendon rupture

Isolated patellar tendon rupture is a rare injury which results in disruption of the extensor mechanism of the knee (1).

• the condition is the third most common type of injury to the extensor mechanism of the knee following patella fracture and quadriceps tendon rupture. (2)
• mainly seen in patients who are in their third and fourth decades (1)
• more common in males than in females (1)

The injury can be

• indirect - more common, caused by rapid contraction of the quadriceps muscles with a flexed knee
• direct - less common, caused by a violent impact against a taut quadriceps tendon (3)

Bilateral simultaneous rupture is seen on rare occasions (e.g. - in chronic systemic diseases) (1).

References:

1. Greis PE, Holmstrom MC, Lahav A.Surgical treatment options for patella tendon rupture, Part I: Acute. Orthopedics. 2005 Jul;28(7):672-9
2. Ramseier LE, Werner CM, Heinzelmann M. Quadriceps and patellar tendon rupture. Injury. Jun 2006;37(6):516-9.
3. Bartalena T et al.Patellar tendon rupture: radiologic and ultrasonographic findings. West J Emerg Med. 2010 Feb;11(1):90-1.