This multicenter registry study (RANGER) reports outcomes for 624 peripheral nerve repairs using processed nerve allograft (Avance) across 31 centers over 10 years. The central question: can processed nerve allograft achieve meaningful recovery comparable to autograft, across nerve types and gap lengths up to 70 mm? The study provides the largest real-world outcomes dataset on this technique to date.
When counseling a patient about nerve gap repair, the choice between autograft, conduit, and processed nerve allograft depends on gap length and injury type. Conduit is only appropriate for gaps under 10 mm — outside that range, outcomes are highly variable and the evidence does not support its use.
Processed nerve allograft achieves 82% meaningful recovery in gaps up to 70 mm, comparable to historical autograft data, without donor site morbidity, additional surgical sites, or the need for immunosuppression.
Two variables most reliably predict worse outcomes: complex injury mechanism (74% vs 94% for neuroma resections) and longer gap lengths (69% at 50–70 mm vs 91% at under 15 mm). When you see a crush or blast injury with a long gap, counsel patients accordingly — this is a biology problem, not just a gap problem.
Timing is more flexible than previously assumed: chronic repairs (repaired more than 90 days out) achieved 83% meaningful recovery, not significantly different from acute repairs. However, motor nerve repairs older than one year after injury were excluded from analysis due to chronic denervation effects — so the flexibility in timing applies to sensory and mixed repairs more than pure motor reconstruction.
This multicenter registry study (RANGER) reports outcomes for 624 peripheral nerve repairs using processed nerve allograft (Avance) across 31 centers over 10 years. The central question: can processed nerve allograft achieve meaningful recovery comparable to autograft, across nerve types and gap lengths up to 70 mm? The study provides the largest real-world outcomes dataset on this technique to date.
When counseling a patient about nerve gap repair, the choice between autograft, conduit, and processed nerve allograft depends on gap length and injury type. Conduit is only appropriate for gaps under 10 mm — outside that range, outcomes are highly variable and the evidence does not support its use.
Processed nerve allograft achieves 82% meaningful recovery in gaps up to 70 mm, comparable to historical autograft data, without donor site morbidity, additional surgical sites, or the need for immunosuppression.
Two variables most reliably predict worse outcomes: complex injury mechanism (74% vs 94% for neuroma resections) and longer gap lengths (69% at 50–70 mm vs 91% at under 15 mm). When you see a crush or blast injury with a long gap, counsel patients accordingly — this is a biology problem, not just a gap problem.
Timing is more flexible than previously assumed: chronic repairs (repaired more than 90 days out) achieved 83% meaningful recovery, not significantly different from acute repairs. However, motor nerve repairs older than one year after injury were excluded from analysis due to chronic denervation effects — so the flexibility in timing applies to sensory and mixed repairs more than pure motor reconstruction.