Graft choices for Anterior Cruciate Ligament Reconstruction

1. Graft choices for Anterior Cruciate
Ligament Reconstruction
Ish Kumar Dhammi et al
Department of Orthopaedics, Guru Teg Bahadur Hospital and UCMS, New
Delhi
Indian Journal of Orthopaedics
| March 2015 | Vol. 49 | Issue 2
Level of evidence III
PRESENTER : Dr SAUMYAAGARWAL
Junior resident Dept of Orthopaedics J.N. Medical College and Dr.
Prabhakar Kore Hospital and MRC, Belgaum

3. INTRODUCTION
• The anterior cruciate ligament (ACL) is the
most commonly injured ligament in sports
persons.
• Available data shows that approximately
3,00,000 ACL reconstructions are performed
every year in USA alone

5. • Various grafts are available for reconstruction of
ACL including :
Autografts -
Bone Patellar Tendon Bone (BPTB),
Hamstring (HS)
Allografts
Synthetic grafts

7. The ideal graft for reconstruction of ACL
• biomechanically similar to native ligament
• easily harvested
• least harvest site morbidity
• secured predictably
• get well incorporated with bone
Till date there is no ideal graft

8. • Autografts > commonly used than allografts or synthetic
grafts
• Autograft commonly used are
BPTB
HS
Bone Quadriceps Tendon (BQT) graft
• Recently, use of allograft is increasing
• Allografts are used to reconstruct ACL primarily in 20–30%
of cases in USA
• Synthetic grafts became popular in 1980 but due to mid-
term poor results lost its efficacy

9. BPTB Graft
• BPTB considered “gold standard” for ACL
reconstruction
• BPTB autograft has excellent clinical results and high
level of patient satisfaction
• Franke K used BPTB graft consisting middle 1/3rd of
patellar tendon with attached patellar and tibial
bone block for first time
• allows fast bone to bone healing within the tibial
and femoral tunnels

11. • long term results (17–20 years) showed
83% of patients having stable, normal or near
normal functions
1.6% of patients needed revision ACL
reconstruction
BPTB
• has high strength and stiffness,
• maintains consistency of size of graft,
• easy to harvest
• can be secured very well in the canal by
interference screws

12. Complications include
• patellar tendon rupture
• patellar/ tibial fracture
• quadriceps weakness
• loss of full extension
• anterior knee pain
• difficulty in kneeling
• numbness due to injury to the infrapatellar
branch of saphenous nerve

13. Hamstring tendon grafts
• The semitendinosus tendon with or without gracilis
tendon is harvested from ipsilateral leg
• used as quadruple stranded grafts and are comparable
to native ACL
Advantages :
• no fear of fracture of patella/tibial tuberosity
• Avulsion
• kneeling pain
• minimizing donor site morbidity.

15. Disadvantages :
• reduced knee flexion strength
• sciatic/ saphenous nerve palsy
• inferior fixation strength
• The long term follow-up results showed 75%
patients scored normal or near normal results
• re-rupture rate was 17%

16. Need for Allograft?
• failure rates high with use of HS grafts
• donor site complications more with BPTB
• Surveys showed use of BPTB graft has declined
progressively
• and use of HS and allograft is increasing, probably
because BPTB graft cannot be used for a double
bundle ACL reconstruction
• Donor site problems have led to search of allografts

17. Allografts
• The commonly used allografts for ACL
reconstruction are
BPTB grafts
HS grafts
Tibialis Posterior/Anterior
Tendo Achilles grafts.

19. • Sterilization with irradiation or ethylene glycol
are recommended to reduce immunogenic
reaction and disease transmission
Advantages of allografts :
• no harvest site morbidity
• predictable graft sizes
• shorter operative time
• ease of use in multiligament and revision
situations
• easier recovery in postoperative period

20. • Disadvantages are :
risk for disease transmission
possible immunogenicity
slower incorporation
• Irradiated allografts are more likely to fail because of
decreased mechanical properties due to sterilization and
possibility of triggering an inflammatory response
• One metaanalysis concluded that allografts were
associated with increased graft failure rates, although
reoperation rates, translation and rotational stability and
functional outcome were similar.

21. Synthetic Ligaments
• carbon fibers
• Gore-Tex
• Dacron
• Kennedy-LAD
• Trevira
• Leeds-Keio
• 1st generation ligaments were knitted woven or braided
• subject to early breakage and tended to elongate.
• 2 ligaments commonly used were (i) proplast made of
Teflon plus carbon
• (ii) polyflex made of polypropylene

23. Complications :
• early rupture
• deposition of carbon
• inflammatory synovitis of knee
• 2nd generation ligaments had additional braided
woven longitudinal and transverse fibers in which
Dacron and Polytetra fluorethylene (PTFE) were
used
• These ligaments allowed fibroblasts in growth, but
suffered with wear, fraying and low abrasion
resistance.

24. • PTFE was used for vascular surgery
• This graft has 5300N tensile strength which is
higher than any other commercially available
ligament (natural ACL in young population has
strength of 1730N)
• Failures :
• mechanical fatigue
• lack of tissue in growth
• presence of wear debris
• rupture rate was 29%

25. Dacron ligament
• has tensile strength of 3631N
• failed due to elongation property
• high rupture rate
• high revision rate

26. • 3rd generation synthetic grafts have
• knitted extra-articular portion with free
longitudinal fibers which resist elongation but
without any braids, to reduce wear debris.
Currently used synthetics are
• Ligament Augmentation Reconstruction System
• Leeds-Keio

27. CONCLUSION
• Ideal graft is yet to be available
• The BPTB graft still remains gold standard
• HS graft has minimal donor site morbidity but
has problems with bone tendon junction healing
and elongation.

28. • Allograft has poor results in terms of re-
rupture rates and immunity
• but can be used in multiligamentous injuries
or in revision.
• Synthetic grafts are still under evolution
• no perfect synthetic graft is available till date.