Soft-tissue anatomy anterior to the human patella

Background: The purpose of this anatomic study is to report the results of dissections of the soft-tissue structures anterior to the human patella. Methods: Sixty-one fresh or fresh-frozen and thawed human cadaver knees were dissected for this study. Thirty-five of the knees were from men, and twenty-six were from women. The soft-tissue structures anterior to the patella were dissected layer by layer and documented photographically. Results: Fifty-seven (93%) of the sixty-one knees were found to have a trilaminar arrangement of fibrous soft-tissue structures anterior to the patella from superficial to deep. Those structures included a transversely oriented fascia, an obliquely oriented aponeurosis, and the longitudinally oriented fibers of the rectus femoris tendon. Between the soft-tissue fibrous layers, there were three prepatellar spaces that can be termed bursae: a prepatellar subcutaneous bursa, a prepatellar subfascial bursa, and a prepatellar subaponeurotic bursa. Four of the sixty-one knees lacked an intermediate oblique aponeurotic layer. In none of the sixty-one knees was there a potential bursal space between the rectus femoris tendon and the anterior patellar bone. Conclusions: These anatomic findings are at variance with descriptions in standard anatomic orthopaedic texts and periodical literature, including the Nomina Anatomica . None of those texts accurately describe the presence of a prepatellar aponeurotic layer or a prepatellar subaponeurotic bursa. Also, in contradistinction to descriptions in the anatomic literature, including the Nomina Anatomica, no prepatellar subtendinous bursa was found in any of the sixty-one knees. Clinical Relevance: With improved knowledge of the prepatellar soft-tissue anatomy, orthopaedic surgeons should be able to more readily identify the extant structures and to better protect and repair them during surgery. This knowledge should also assist both orthopaedic surgeons and radiologists in the interpretation of soft-tissue imaging of the knee.