B. Oakes (Cheltenham, AU)

BWO one of first to culture chondrocytes in vitro in a differentiated state using both biochemical and ultrastructural parameters. Also first to determine that chondrocytes must be cultured at high density to maintain their differentiated state. First to recognise that ACL autografts & allografts collagen is foreign to the intra-articular space and is totally removed in both animal and humans over 6-9 months such that small diameter collagen fibrils predominate causing poor biomechanical performance of ALL ACLR procedures with UTS <45% of the control non-operated side. This essential cell biology of ACLR is still poorly recognised by surgeons world wide. Only recently is there serious doubts about the validity of ACLR procedures. The recognition that ACI and MACI still does not create normal "neo-hyaline articular cartilage" with normal large PG molecules in the human is just beginning to be recognised. There are no current surgical procedures that can produce/repair AC defects in the human which will endure > 5 years without mechanical problems due to poor repair graft quality.

Presenter Of 1 Presentation

Poster Extracellular Matrix

P023 - A Quantitative Collagen Fibril Population Analyses of 39 Jone’s Free ACL Autografts vs Time

Presentation Topic
Extracellular Matrix
Date
13.04.2022
Lecture Time
09:30 - 09:30
Room
Exhibition Foyer
Session Name
7.3 - Poster Viewing / Coffee Break / Exhibition
Session Type
Poster Session
Disclosure
No Significant Commercial Relationship

Abstract

Purpose

Why do so many Anterior Cruciate Ligament Reconstructions (ACLR’) fail/rupture in the young athlete ?

In my country one Australian Rules Football (ARF) player had 5 ACLR’s in 5 years & ALL failed !

Uribe et al. CORR 325:91-99,1996 and others have noted from 3-22% recurrent patholaxity.

Also recently L.J.Salmon et al AJSM 2018;46(3):531 has reported recently the high graft overt rupture rate of ACLR in athletes < 20 yrs old of ~ 36% !!

In (2020) in Carlsbad, Bert Mandelbaum, an experienced ACLR surgeon displayed a failed ACLR in an NFL player.

Methods and Materials

Biopsies of human ACL autografts from 6 months implantation to 10 years post-implantation were obtained in patients with meniscal and or articular cartilage lesions.

Quantitative ultrastructural studies of collagen fibril populations using specific software were performed on human 39 ACL autografts using the PT, Hamstrings, IT band and were compared to the normal ACL and PT.

Results

The outstanding feature was the absence of large diameter collagen fibrils >100nm after 6 months post-surgery and the predominance of small diameter fibrils <100nm diameter which were not arranged in normal fasciculi. The ACL graft itself was usually lax, soft and easily probed compared to the robust and firm nature of the normal ACL when probed and defined as two distinct bundles.

Conclusion

All the ACL autografts except at 6 weeks contained predominantly small fibrils < 100nm diameter.

Large fibrils > 100nm were not replaced at 10 years post-implantation.

This is a ‘de-ligamentization’ of these autografts.

This tissue if of poor tensile quality and is doomed to failure either by creep elongation or complete grade 3 overt failure.

Collapse

Presenter Of 1 Presentation

Extracellular Matrix

P023 - A Quantitative Collagen Fibril Population Analyses of 39 Jone’s Free ACL Autografts vs Time

Abstract

Purpose

Why do so many Anterior Cruciate Ligament Reconstructions (ACLR’) fail/rupture in the young athlete ?

In my country one Australian Rules Football (ARF) player had 5 ACLR’s in 5 years & ALL failed !

Uribe et al. CORR 325:91-99,1996 and others have noted from 3-22% recurrent patholaxity.

Also recently L.J.Salmon et al AJSM 2018;46(3):531 has reported recently the high graft overt rupture rate of ACLR in athletes < 20 yrs old of ~ 36% !!

In (2020) in Carlsbad, Bert Mandelbaum, an experienced ACLR surgeon displayed a failed ACLR in an NFL player.

Methods and Materials

Biopsies of human ACL autografts from 6 months implantation to 10 years post-implantation were obtained in patients with meniscal and or articular cartilage lesions.

Quantitative ultrastructural studies of collagen fibril populations using specific software were performed on human 39 ACL autografts using the PT, Hamstrings, IT band and were compared to the normal ACL and PT.

Results

The outstanding feature was the absence of large diameter collagen fibrils >100nm after 6 months post-surgery and the predominance of small diameter fibrils <100nm diameter which were not arranged in normal fasciculi. The ACL graft itself was usually lax, soft and easily probed compared to the robust and firm nature of the normal ACL when probed and defined as two distinct bundles.

Conclusion

All the ACL autografts except at 6 weeks contained predominantly small fibrils < 100nm diameter.

Large fibrils > 100nm were not replaced at 10 years post-implantation.

This is a ‘de-ligamentization’ of these autografts.

This tissue if of poor tensile quality and is doomed to failure either by creep elongation or complete grade 3 overt failure.

Collapse