Extensor Mechanism Injuries of the Knee

- See:
       - Rupture of the Quadriceps
       - Patellar Tendon Injury
       - Tibial Tubercle Frx

- Discussion:
    - extensor mechanism includes quadriceps, quadriceps tendon, medial & lateral retinaculum, patellofemoral and patellotibial ligaments, Patellar Tendon (ligament), and tibial tubercle;
    - superficial location of extensor mechanism make it suseptable to injury;
    - extensor mechanism rupture may involve either the quadriceps tendon or patellar ligament and may be either partial or complete;
          - complete rupture is rare in young athlete unless assoc w/ steroids;
          - patellar ligament ruptures usually occur in pts < 40 yrs of age & quads tendon ruptures in pts older than 40 years of age;
    - risk factors:
          - RA, long-term diabetes mellitus, and long-term steroid use;
    - Diff Dx:
          - Osgood-Schlatter disease, Sindig-Larsen-Johanssen dz
          - consider anatomic malalignment: Chondromalacia
          - MVA (dashboard injury);
          - patellofemoral arthritis in those over 40 yrs;
          - disproportionate extensor mechanism pain: following trauma or surgery consider sympathetic dystrophy;
                 - disproportionate pain, stiffness, skin discoloration, & decreased skin temperature

Evaluation of the Medial Soft-Tissue Restraints of the Extensor Mechanism of the Knee.

The effect of external load on torque production by knee extensors.

Evaluation of the medial soft-tissue restraints of the extensor mechanism of the knee.

Biomechanical effects of different surgical procedures on the extensor mechanism of the patellofemoral joint.

Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Thursday, August 30, 2012 3:56 pm