A Multicenter, Prospective, Randomized, Pilot Study of Outcomes for Digital Nerve Repair in the Hand Using Hollow Conduit Compared With Processed Allograft Nerve

Abstract

Background: Current repair options for peripheral nerve injuries where tension-free gap closure is not possible include allograft, processed nerve allograft, and hollow tube conduit. Here we report on the outcomes from a multicenter prospective, randomized, patient-and evaluator-blinded, pilot study comparing processed nerve allograft and hollow conduit for digital nerve reconstructions in the hand. Methods: Across 4 centers, consented participants meeting inclusion criteria while not meeting exclusion criteria were randomized intraoperatively to either processed nerve allograft or hollow conduit. Standard sensory and safety assessments were conducted at baseline, 1, 3, 6, 9, and 12 months after reconstruction. The primary outcome was static 2-point discrimination (s2PD) testing. Participants and assessors were blinded to treatment. The contralateral digit served as the control. Results: We randomized 23 participants with 31 digital nerve injuries. Sixteen participants with 20 repairs had at least 6 months of follow-up while 12-month follow-up was available for 15 repairs. There were no significant differences in participant and baseline characteristics between treatment groups. The predominant nerve injury was laceration/sharp transection. The mean ± SD length of the nerve gap prior to repair was 12 ± 4 mm (5-20 mm) for both groups. The average s2PD for processed allograft was 5 ± 1 mm (n = 6) compared with 8 ± 5 mm (n = 9) for hollow conduits. The average moving 2PD for processed allograft was 5 ± 1 mm compared with 7 ± 5 mm for hollow conduits. All injuries randomized to processed nerve allograft returned some degree of s2PD as compared with 75% of the repairs in the conduit group. Two hollow conduits and one allograft were lost due to infection during the study. Conclusions: In this pilot study, patients whose digital nerve reconstructions were performed with processed nerve allografts had significantly improved and more consistent functional sensory outcomes compared with hollow conduits.

Failed peripheral nerve reconstruction with processed nerve allografts in three patients

“…Dear Sir, Repair of peripheral nerve injuries with segmental loss is challenging, partly because the amount of available nerve autograft is limited. Processed nerve allografts (PNAs) have recently been reported to perform well in sensory, mixed and motor defects between 5-50 mm, with a meaningful recovery rate of 76-100% (Brooks et al, 2012;Cho et al, 2012;Means et al, 2016). We present three patients treated with PNA Avance Ò Nerve graft (AxoGen Inc., FL, USA) with poor results owing to resorption of the PNA.…”

Sensory restoration of breast reconstruction – The search for the ideal approach continues

“…Nerve allografts have successfully been used for various indications at various anatomical sites and for nerve gaps up to 70 mm in length . Current data show nerve allografts are associated with clinical results comparable to nerve autografts, and significantly better than hollow tube conduits . As such, it is reasonable to use nerve allografts in breast neurotization when primary coaptation is not feasible.…”

A Survey of the Prevalence and Practice Patterns of Human Acellular Nerve Allograft Use

“… 4 , 13 Some recent studies suggest that larger gaps may also be reconstructed with HANA. 6 , 14 , 15 …”

“…There are 2 clinical studies sponsored by AxoGen, Inc., (Alachua, Fla.) and a literature review that suggests that HANA may be a better and more reliable option than nerve conduit. 6 , 17 , 18 It is surmised that this is related to the inherent nerve structure within HANA when compared with the empty chamber of nerve conduits.…”