This 2006 systematic review by Duthon et al. synthesizes original research on ACL macroanatomy and microanatomy. It covers gross dimensions, the two-bundle functional model, collagen ultrastructure, innervation, and vascularization. The goal is to explain what the ACL is structurally and why it behaves as it does mechanically and biologically.
The ACL's failure to heal is not a clinical inconvenience but a structural inevitability. The avascular fibrocartilaginous zone near the tibial attachment, combined with the absence of vessels crossing either bony attachment, means no scaffold for intrinsic repair exists.
When counseling a young athlete after ACL rupture, the case for surgical reconstruction rests on this anatomy. Conservative management cannot restore the 82–89% anterior restraint function that the intact ligament provides at 30° flexion.
The differential bundle behavior also has direct surgical implications. When you see residual rotatory instability after single-bundle reconstruction, this paper is why. The PLB, dominant in extension, is not reconstructed in traditional single-bundle techniques. Double-bundle reconstruction emerged specifically to address this gap.
Preserving ACL remnant tissue during reconstruction is worth considering: mechanoreceptor loss after rupture directly reduces quadriceps voluntary activation, and remnant preservation may help restore proprioceptive feedback that a graft alone cannot provide.
This 2006 systematic review by Duthon et al. synthesizes original research on ACL macroanatomy and microanatomy. It covers gross dimensions, the two-bundle functional model, collagen ultrastructure, innervation, and vascularization. The goal is to explain what the ACL is structurally and why it behaves as it does mechanically and biologically.
The ACL's failure to heal is not a clinical inconvenience but a structural inevitability. The avascular fibrocartilaginous zone near the tibial attachment, combined with the absence of vessels crossing either bony attachment, means no scaffold for intrinsic repair exists.
When counseling a young athlete after ACL rupture, the case for surgical reconstruction rests on this anatomy. Conservative management cannot restore the 82–89% anterior restraint function that the intact ligament provides at 30° flexion.
The differential bundle behavior also has direct surgical implications. When you see residual rotatory instability after single-bundle reconstruction, this paper is why. The PLB, dominant in extension, is not reconstructed in traditional single-bundle techniques. Double-bundle reconstruction emerged specifically to address this gap.
Preserving ACL remnant tissue during reconstruction is worth considering: mechanoreceptor loss after rupture directly reduces quadriceps voluntary activation, and remnant preservation may help restore proprioceptive feedback that a graft alone cannot provide.