PMID- 11211097
OWN - NLM
STAT- MEDLINE
DCOM- 20010607
LR  - 20190921
IS  - 0920-5063 (Print)
IS  - 0920-5063 (Linking)
VI  - 11
IP  - 8
DP  - 2000
TI  - Clinical long-term in vivo evaluation of poly(L-lactic acid) porous conduits for 
      peripheral nerve regeneration.
PG  - 869-78
AB  - It was the purpose of this study to evaluate the clinical long-term effects of 
      PLLA degradation in vivo on nerve regeneration in the rat sciatic nerve model. 
      Thirty-one Sprague Dawley rats were utilized. Two groups of animals were 
      selected. The control group of 10 animals received a 12 mm reversed isograft into 
      the right sciatic nerve from 5 donor animals. The experimental group (n = 21) 
      received a 12 mm empty PLLA conduits placed into a 12 mm defect in the right 
      sciatic nerve. The left leg served as an internal control. Walking track analysis 
      was performed monthly through 8 months. At the end of 4 and 8 months, animals in 
      the control isograft and experimental group had the medial and lateral 
      gastrocnemius muscles harvested and weighed for comparison. The 
      midconduit/isograft and the distal nerve in these same animals were harvested and 
      histomorphologically analyzed. Multiple samples were collected and expressed as 
      means +/- standard error. A two-sample t-test and Wilcoxon rank sum test was used 
      to compare the variables. Significance level was set at alpha = 0.05. After 
      Bonferroni correction for multiple testing, a p value of < or = 0.01 was 
      considered statistically significant. Throughout all time periods, the PLLA 
      conduit remained structurally intact and demonstrated tissue incorporation and 
      vascularization. There was no evidence of conduit collapse or breakage with limb 
      ambulation. Moreover, there was no evidence of conduit elongation at 8 months as 
      previously observed with the 75:25 poly(DL-lactic-co-glycolic acid) (PLGA) 
      conduits. The mean absolute value of the sciatic functional index (SFI) 
      demonstrated no group differences from isograft controls measured over the 8 
      months except at 3 months where the isograft values were higher (p = 0.0379) and 
      at 7 months were the isograft group was significantly lower (p = 0.0115). At 4 
      and 8 months, the weight of the gastrocnemius muscles of the experimental group 
      was not significantly different from isografts. At 4 months the number of 
      axons/mm2 and nerve fiber density was not significantly different between the 
      isograft control and experimental groups in either the midconduit/isograft or 
      distal nerve. At 8 months the number of axons/mm2 was significantly lower in the 
      isograft compared to the midconduit experimental group (p = 0.006). The number of 
      axons/mm2 in the distal nerve and the nerve fiber density in the midconduit and 
      distal nerve were not significantly different between the two groups. The study 
      confirmed our initial hypothesis that PLLA conduits are a viable scaffold for 
      clinical long-term nerve gap replacement. We are critically aware however that 
      longer evaluation of polymer degradation is warrented. Further studies on these 
      individual nerve components are continuing, with the ultimate goal being the 
      fabrication of a bioactive conduit that meets or exceeds the functional results 
      of isografts.
FAU - Evans, G R
AU  - Evans GR
AD  - Department of Plastic Surgery, The University of Texas, M. D. Anderson Cancer 
      Center, Houston 77030, USA. Gevans@notes.mdacc.tmc.edu
FAU - Brandt, K
AU  - Brandt K
FAU - Niederbichler, A D
AU  - Niederbichler AD
FAU - Chauvin, P
AU  - Chauvin P
FAU - Herrman, S
AU  - Herrman S
FAU - Bogle, M
AU  - Bogle M
FAU - Otta, L
AU  - Otta L
FAU - Wang, B
AU  - Wang B
FAU - Patrick, C W Jr
AU  - Patrick CW Jr
LA  - eng
GR  - CA-16672/CA/NCI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - England
TA  - J Biomater Sci Polym Ed
JT  - Journal of biomaterials science. Polymer edition
JID - 9007393
RN  - 0 (Membranes, Artificial)
RN  - 0 (Polyesters)
RN  - 0 (Polymers)
RN  - 33X04XA5AT (Lactic Acid)
RN  - 459TN2L5F5 (poly(lactide))
SB  - IM
MH  - Animals
MH  - Axons/physiology
MH  - Lactic Acid/*chemistry/pharmacology
MH  - *Membranes, Artificial
MH  - Muscle, Skeletal/physiology
MH  - Nerve Fibers/physiology
MH  - Peripheral Nerves/*metabolism/*physiology
MH  - Polyesters
MH  - Polymers/*chemistry/pharmacology
MH  - *Prostheses and Implants
MH  - Rats
MH  - Rats, Sprague-Dawley
MH  - *Regeneration
MH  - Sciatic Nerve/chemistry
MH  - Time Factors
MH  - Walking
EDAT- 2001/02/24 12:00
MHDA- 2001/06/08 10:01
CRDT- 2001/02/24 12:00
PHST- 2001/02/24 12:00 [pubmed]
PHST- 2001/06/08 10:01 [medline]
PHST- 2001/02/24 12:00 [entrez]
AID - 10.1163/156856200744066 [doi]
PST - ppublish
SO  - J Biomater Sci Polym Ed. 2000;11(8):869-78. doi: 10.1163/156856200744066.