One-stage human acellular nerve allograft reconstruction for digital nerve defects

Comparison of nerve conduits and nerve graft in digital nerve regeneration: A systematic review and meta-analysis

The goal of this systematic review and meta-analysis was to compare nerve conduits and nerve graft for peripheral nerve regeneration. This type of lesion frequently causes disability due to pain, paresthesia and motor deficit. On the PICO process, "P" corresponded to patients with peripheral digital nerve lesions of any age, gender or ethnicity, "I" to interventions with nerve conduits or nerve graft, "C" to the control group with no treatment, placebo or receiving other treatment, and "O" to outcome assessment of nerve regeneration. Initial search found in 3859 studies, including 2001 duplicates. The remaining 1858 studies were selected by title and/or abstract; 1798 articles were excluded, leaving 60 articles for full-text review. Thirty-nine of these 60 reports were excluded as not meeting our inclusion criteria, and 21 articles were ultimately included in the systematic review. For patients older than 40 years, there was a greater mean improvement on S2PD and M2PD tests with grafting, which seemed to be the better surgical technique, positively impacting prognosis. On the M2PD test, there was significantly greater improvement in 11-17.99 mm defects with grafting (P < 0.001); this finding should guide surgical strategy in peripheral nerve regeneration, to ensure better outcomes.

Customized reconstruction of a complex soft-tissue defect around the knee with a free perforator flap

Reconstruction of a complex defect around the knee, particularly involving a large soft-tissue defect or disruption of the extensor mechanism, is always a challenging problem. The purpose of this study was to introduce the use of a customized free perforator flap for complex soft-tissue reconstruction around the knee. Between June 2010 and March 2017, 16 patients underwent this procedure. The choice of flap design is based on the location of the wound, the required pedicle length, the missing tissue components and their volumes, and the risk of donor-site morbidity. The reconstruction was performed using anterolateral thigh perforator (ALTP) flaps in five cases, modified ALTP flaps in two cases, chimeric ALTP flaps in four cases, dual-skin paddle ALTP flaps in two cases, and chimeric thoracodorsal artery perforator flaps in two cases. Multiple perforator flaps and vascularized fascia lata were used in one case. All flaps survived postoperatively. No vascular congestion was observed, and partial necrosis was observed in only one case. Primary closure of the donor site was performed for all patients. At a mean follow-up time of 16.5 months, most cases showed satisfactory flap contours and acceptable functional outcomes. A free perforator flap is a reliable option for repairing complex soft-tissue defects in the knee region, especially when local and pedicled flaps are unavailable. Various flap designs allow for more individualized treatment approaches and can achieve better results.

A Retrospective Case Series Reporting the Outcomes of Avance Nerve Allografts in the Treatment of Peripheral Nerve Injuries

BACKGROUND

Acellular nerve allografts are a viable treatment modality for bridging nerve gaps. Several small studies have demonstrated results equal to those of autologous grafts; however, there is information lacking with regard to outcomes for wider indications. The authors evaluated the outcomes of patients treated with a nerve allograft in a variety of clinical situations.

METHODS

A retrospective chart analysis was completed between April of 2009 and October of 2017. Inclusion criteria were age 18 years or older at the time of surgery and treatment with a nerve allograft. Patients were excluded if they had not been followed up for a minimum of 6 months. The modified Medical Research Council Classification was used to monitor motor and sensory changes in the postoperative period.

RESULTS

Two hundred seven nerve allografts were used in 156 patients; of these, 129 patients with 171 nerve allografts fulfilled the inclusion criteria. Seventy-seven percent of patients achieved a sensory outcome score of S3 or above and 36 percent achieved a motor score of M3 or above. All patients with chronic pain had improvement of their symptoms. Graft length and diameter were negatively correlated with reported outcomes. One patient elected to undergo revision surgery, and the original graft was shown histologically to have extensive central necrosis. Anatomically, allografts used for lower limb reconstruction yielded the poorest results. All chronic patients had a significantly lower postoperative requirement for analgesia, and allografts were effective in not only reducing pain but also restoring a functional level of sensation.

CONCLUSIONS

This study supports the wider application of allografts in managing nerve problems. However, caution must be applied to the use of long grafts with larger diameters.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Autograft Substitutes: Conduits and Processed Nerve Allografts

Manufactured conduits and allografts are viable alternatives to direct suture repair and nerve autograft. Manufactured tubes should have gaps less than 10 mm, and ideally should be considered as an aid to the coaptation. Processed nerve allograft has utility as a substitute for either conduit or autograft in sensory nerve repairs. There is also a growing body of evidence supporting their utility in major peripheral nerve repairs, gap repairs up to 70 mm in length, as an alternative source of tissue to bolster the diameter of a cable graft, and for the management of neuromas in non-reconstructable injuries.