AAHS ASPN ASRM - 2013 Annual Meeting - American Association ...

Cryopreservation of Epineural Sheath Conduits Gives Similar Functional Results as Cold Storage
Institution where the work was prepared: Cleveland Clinic, Cleveland, OH, USA
Michal Molski; Yalcin Kulahci; Ilker Yazici; Maria Siemionow; Cleveland Clinic
INTRODUCTION:
For reconstruction of long nerve defects, more autograft material is needed. Allogenic nerve transplantation (ANT) provides access to unlimited sources of nerve
grafts but requires immunosuppression. To reduce nerve immunogenicity, cold preservation was used in the past. Epineural sheath allotransplantation provides
unlimited amount of grafting material, but cold storage is time limited. Epineural sheaths storage in cryogenic conditions will increase availability of grafting
material and will allow for unlimited nerve banking. PURPOSE: To compare the effect of cold storage (CS) and cryopreservervation (CR) of isogenic and allogenic
epineural sheaths (ES) on functional outcome following rat sciatic nerve gap repair.
MATHERIAL AND METHODS:
24 Lewis rat recipients were divided into 4 groups of 6 animals each. ES were harvested from Brown Norway rats (n=12) and Lewis rats (n=12), 6 isogenic and
6 allogenic grafts were stored in UW solution for 21 days in +4C, remainder were cryopreserved in liquid nitrogen. A 25mm gap was created in recipient's sciatic
nerve and defect was bridged in following group: 1) with cold stored isogenic ES; in group 2) cold stored allogenic ES; in group 3) cryopreserved isogenic
ES; and in group 4) cryopreserved allogenic ES. Recipients of allografts received 7 day protocol of ??TCR and CsA. Non-operated contralateral sites served as
normal controls. At 24 weeks nerve regeneration was evaluated by pin prick, toe spread test somatosensory evoked potentials examination (SSEP) and gastrocnemius
muscle index (GMI).
RESULTS:
There was no difference in pin prick between groups. Toe spread results were 2.7; 1.0; 3.0; 1.4 in group 1,2,3 and 4 respectively. When compared to normal
values SSEP result were 89%; 87%; 93%; 89% in group 1,2,3 and 4 respectively. Gastrocnemius muscle index values were 21%; 28%; 18.4%; 18.2% in group
1,2,3 and 4 respectively when compared to muscle weight of control side.
CONCLUSIONS:
Repair of 25mm gap of rat sciatic nerve with cryopreserved allogenic epineural sheath grafts resulted in functional results comparable to cold stored allogenic epineural
sheath grafts. In isogenic groups functional recovery in cryopreserved epineural sheath group was better comparable to cold storaged group. Cryopreservation may
be more applicable method for storage of nerve allogenic material since it allows for longer graft storage with comparable functional outcome after
Outcome of Neurolysis for Failed Tarsal Tunnel Syndrome
Institution where the work was prepared: Johns Hopkins University, Baltimore, MD, USA
A. Lee Dellon, MD1; Allison R. Barker, BA2; Gedge D. Rosson1; (1)Johns Hopkins University, (2)Johns Hopkins University School of Medicine
While surgery to treat median nerve compression and failed carpal tunnel decompression is well-described, experiences with decompressing the tibial nerve in
the tarsal tunnels are not well-described. There have only been two reports of the treatment of failed tarsal tunnel surgery. This is the largest reported series
of tarsal tunnel revision surgery reported.
Revision tarsal tunnel surgery was performed on 44 patients (two bilaterally). The surgical procedure included a neurolysis of the tibial nerve in the tarsal tunnel,
the medial plantar, lateral plantar, and calcaneal nerves in their respective tunnels, and excision of the inter-tunnel septum. For patients with an associated
painful scar, neuroma resection of the posterior branch of the saphenous nerve and/or resection of a calcaneal nerve branch, plus muscle implantation, was
included. Post-operatively, immediate ambulation was permitted.
Outcomes were assessed were assessed by someone other than the surgeon, with a numerical grading scale that included neurosensory measurements (0 = normal,
10 = most severely impaired). Outcomes were also assessed by patient satisfaction and their own estimate of residual pain and/or numbness. Mean follow-up
time was 2.2 years. (range 1 to 4 years).
Results in terms of patient satisfaction were 54% excellent, 24% good, 13% fair, and 9% poor results. Results in terms of numerical grading demonstrated a
significant improvement (p