The Relationship Between Additional Heads of the Quadriceps Femoris, the Vasti Muscles and the Patellar Ligament

Abstract

Introduction: The quadriceps femoris consists of four muscles: the rectus femoris, vastus medialis, vastus intermedius and vastus lateralis. However, the effect of additional quadriceps femoris heads on the vasti muscles and patellar ligaments is unknown.Materials and Methods: One hundred and six lower limbs (34 male and 19 female cadavers) fixed in 10% formalin were examined.Results: On all lower extremities, the vastus lateralis consisted of superficial, intermediate and deep layers. The vastus medialis, on the other hand, consisted of only the longus and obliquus layers. Additional quadriceps femoris heads affected both the vasti muscles and the patellar ligaments.Conclusion: There is a strong correlation between the presence of accessory quadriceps femoris heads and effects on vasti muscles and patellar ligament.

Quadriceps femoris muscle: anatomical variations, population frequencies and clinical implications

“…This could be due to the layered composition of quadriceps femoris tendon which is ussualy structured in 4 layers: (1) superficially the rectus femoris tendon, (2) superficial portion of vastus medialis and vastus lateralis, (3) the intermediate portion of vastus lateralis and (4) deeply the vastus intermedius [42]. However, more layers can be found in the quadriceps femoris tendon in the case of the presence of additional heads such as a fifth layer when there is 5, 6 and even 8 quadriceps femoris heads [43]. Also, the variations of patellar ligament insertion angle could be related with the variability between subjects in quadriceps extension function during walking after anterior cruciate ligament injury, the development of degenerative damages of the knee cartilage, and with fat-pad and tendon pathologies [44,45].…”