TY  - JOUR
T1  - Displaced Longitudinal Stress Fracture of the PatellaA Case Report
AU  - Sillanpää, Petri J.
AU  - Paakkala, Antti
AU  - Paakkala, Timo
AU  - Mäenpää, Heikki
AU  - Toivanen, Jarmo
Y1  - 2010/10/06
N1  - 10.2106/JBJS.I.01472
JO  - The Journal of Bone & Joint Surgery
SP  - 2344
EP  - 2347
VL  - 92
IS  - 13
N2  - 
Stress fractures often occur in physically active individuals as a result of repetitive strenuous muscle and tendon forces acting on bones that have not adapted to such forces1-3. To our knowledge, the literature contains no reports of displaced longitudinal stress fractures of the patella requiring open reduction and internal fixation. The quadriceps muscle and patellar tendon produce extensive forces that can result in a displaced transverse patellar stress fracture2-7. The less strong vertical patellar restraints, including the medial patellofemoral ligament8, produce most of the ligamentous patellar stability in the lateral direction near knee extension8. In cases of acute traumatic patellar dislocation, the osseous structure of the patella is compromised mostly in the lateral direction—e.g., by avulsion of the medial patellofemoral ligament insertion—causing a medial margin fracture of the patella9. We are not aware of any previous reports of repetitive stress causing a displaced longitudinal patellar stress fracture.

SN  - 0021-9355
M3  - doi: 10.2106/JBJS.I.01472
UR  - http://dx.doi.org/10.2106/JBJS.I.01472
ER  -