Update on ACL reconstruction, with information on current direction of demineralized bone matrix (DBM) use in bone tunnels and biocartilage on chondral lesions
1. Update on the ACL
Alan M. Hirahara, M.D., FRCS(C)
Board Certified in Orthopaedic Surgery & Orthopaedic Sports Medicine
Specializing in arthroscopic shoulder surgery
Medical Director Team Physician Consultant
Sacramento State Athletics Sacramento River Cats Oakland A’s
MiLB - AAA
3. Instability Tests
• Examine contralateral leg
• Relax the patient
– Difficult with acute injuries / Re-examine
• Gentle then repeat several times to determine
maximum stress tolerated
• Degree of instability
• Quality of instability (“End Point”)
6. Pivot Shift
• Anterolateral instability
• Lateral tibial plateau
subluxes in extension
• Reduces in flexion by IT
band
Grade I – Glide into place
Grade II – Pops into place
Grade III – Doesn’t reduce
16. Results of ACL Recon
• Meta-analysis • Allograft comparable to
demonstrates newer autograft for long term
techniques with 4HS vs. stability
BTB produces higher – But debatable whether less
stability rates and are morbidity
– 1 : 1.5 to 4 million risk of
fixation dependent
disease transmission
– 77 – 80% Normal stability
– 4.4 – 5.9% Instability rates
Prodromos et al, Arthroscopy, 21(10) 2005.
Sherman et al, Arthroscopy, 20(9) 2004.
18. Demineralized Bone Matrix
• Allograft bone with inorganic mineral removed, leaving only organic
collagen matrix
• Increased osteoinductivity
– Exposed growth factors (BMP’s)
• Requires a carrier
• Many clinical studies showing efficacy but each product has different
characteristics
19. DBM
Osteoinduction
Carrier Terminal
Product Distributor Assay – Test
% DBM (by wt) Sterility?
Every Lot?
RPM Yes In Vivo
StimuBlast Arthrex
(36) E-Beam Yes
Wright CaSO4 Yes In Vitro
AlloMatrix
Medical (40) E-Beam Yes
Na Hyaluronate In Vivo / In Vitro
DBX Synthes No
(32) Yes
Glycerol In Vivo
Grafton Medtronic No
(17) No
20. Reverse Phase Medium (RPM)
• Mod Pluronic F127 (Poloxamer PPO PEO)
5 min
• More viscous at body temp
• Resists irrigation, can use arthroscopically
• Permeable to blood, resorbed
• Metabolized readily
RPM Glycerol
22. Etiology of ACL Tunnel Widening
Biological Mechanical
• Synovial fluid propagation • Graft position
• Increased cytokine levels • Fixation method
• Sterilization methods
• Implant material
• Graft type
• Graft donor
Maak et al. JAAOS. 2010; 18: 695-706.
Fauno et al. Arthoscopy. 2005; 21(11): 1337-41.
Wilson et al. AJSM. 2004; 32(2): 543-9.
Darabos et al. Knee Surg Sports Traum Arthrsc; 2011; 19: S36-46.
Rodeo et al. AJSM. 2006; 34(11): 1790-800.
23. Potential Consequences
• Delaying incorporation of the soft tissue graft
into bone
• Decreasing graft stability
• Causing difficulty with future revision surgery
30. The effect of biologic treatments on
ACL reconstruction tunnel widening
– a randomized clinical trial
Investigators:
Alan Hirahara MD, FRCSC, Private Practice, Sacramento CA
Thomas M. DeBerardino, MD, U of Connecticut Health Center