– Allograft tissue for bridging nerve
discontinuities• From donated human peripheral nerves• Decellularized and sterile• Provides clean and clear pathways for
axons to grow through
– Shown to be superior to Type I Collagen Tube (Whitlock et al 2009)
– Clinical Study from Mayo Clinic (Karabekmez et al 2009)
• Demonstrates re-incorporation of allograft
• Excellent recovery of 2PD in 5-30 mm deficits
(Karabekmez et al., Hand, 2009 )
© AxoGen 2009
© AxoGen 2009
Handles similar to autograftCleansed and sterile
3-D ECM structure maintained Size matching: Lengths up to 50mm & diameters up to 5mm
The Natural Connection
©AxoGen 2009
©AxoGen 2009
©AxoGen 2009
Nerve Autograft Conduit
Hours
Days
Weeks
Months
Years
Bridging the Gap:Different Mechanisms for Repair
Hours
Days
Months
Years
How Nerve Conduits Work:Mechanism for Repair
Fluid seeps into the void of the conduit.Fluid seeps into the void of the conduit.
An hourglass shaped fibrin cable forms.An hourglass shaped fibrin cable forms.
Cell migration and axonal regeneration occurs, restricted by the thinnest portion.
Cell migration and axonal regeneration occurs, restricted by the thinnest portion.
Often the resulting tissue is visibly thinner, containing a limited number of regenerated axons.
Often the resulting tissue is visibly thinner, containing a limited number of regenerated axons.
Increasing Gap Length
Length Limitations of Conduits:Mechanism for Repair
At short gap lengths, the fibrin cable is robust enough to allow regeneration.
At short gap lengths, the fibrin cable is robust enough to allow regeneration.
Thinning restricts the regenerative space at longer gaps.
Thinning restricts the regenerative space at longer gaps.
Decreasing Effi
cacy
The cable does not form when length limits are exceeded. This can result in no regeneration or a neuroma.
The cable does not form when length limits are exceeded. This can result in no regeneration or a neuroma.
Clinical Outcomes with Conduits:Landmark Studies
Type of Nerve Gap Length % Failure* Other Findings Clinical PublicationDigital Nerves(Sensory)
0-4mm5-7mm8-25mm
0%39%29%
34% failure rate in gaps 5mm or greater
Weber et al, 2000.
Digital Nerves(Sensory)
6-18mm 25% 100% of gaps greater than 16mm failed
Lohmeyer et al, 2009.
Digital Nerves(Sensory)
5-30mm 14% 27% reported poor resolution of pain
Mackinnon et al, 1990.
Sensory, mixed and motor nerves
2.5-20mm 57% 31% required revision Wangensteen et al, 2009.
* No or poor sensory recovery as defined by MRCC scale.* No or poor sensory recovery as defined by MRCC scale.
Avance® provides 3-D scaffolding to support the body’s own regeneration process.
Clean and clear pathways allow cell migration and axonal regeneration.
Axon regeneration is well-distributed throughout the cross-section.
Avance® is incorporated into the patient’s own tissue.
Hours
Days
Months
Years
How Avance® Works:Mechanism for Repair
Preclinical Comparative Study(Whitlock et al., Muscle Nerve, 2009)
Electrical Stimulation(28 mm, 22 Weeks)
Test Group Positive Responses
Conduit 0/9
Allograft(Avance®
process)7/9
Isograft 9/9
Isograft AxoGen® NeuraGen®
28mm, 22 weeks (midgraft). Scale bars = 20µm
Summary of Results: “AxoGen processed allografts are superior to a currently available conduit-style nerve guide,
the Integra NeuraGen®.”
•6 weeks, 14mm gapAllograft>20x Myelinated Fibers vs. Conduit
•22 weeks, 28mm gapAllograft>20x Myelinated Fibers vs. Conduit
Avance® Clinical Study(Karabekmez et al., Hand, 2009)
- 10 nerve injuries, gaps ranging from 0.5 to 3cm
- Sensory improvement in all patients
- Data at 9 months shows recovery in the excellent range• Moving 2PD: 4.4mm, Static 2PD: 5.5mm
- Graft shown to be re-incorporated into the repair site• 8 weeks post Avance® implant patient
returned for a revision of his Dupuytren’s contracture repair
• At ~20 wks moving 2PD was 7mm