Medical device

Abstract

The present invention provides a peripheral nerve growth conduit for peripheral nerve repair, in particular conduits through which peripheral nerves can grow. The conduit includes poly-ε-caprolactone (PCL). Preferably, the inner (luminal) surface of the conduit comprises pits having a depth of 1-4 μm. Suitably, the conduit may also include poly-lactic acid (PLA). The inner surface of the conduit may have been treated with an alkaline composition. The present invention also provides a method for treating a peripheral nerve damage using a peripheral nerve growth conduit including poly-ε-caprolactone (PCL). The present invention also provides a kit for treating a peripheral nerve damage having a peripheral nerve growth conduit including poly-ε-caprolactone (PCL).

1 . A peripheral nerve growth conduit including poly-ε-caprolactone (PCL) wherein the inner (luminal) surface of the conduit comprises pits (blind holes). 
     
     
         2 . A peripheral nerve growth conduit according to  claim 1 , wherein the pits have an average diameter in the range 1-10 μm. 
     
     
         3 . A peripheral nerve growth conduit according to  claim 1 , wherein the pits have an average depth in the range 1-4 μm. 
     
     
         4 . A peripheral nerve growth conduit according to  claim 1 , wherein the % coverage of the pits is in the range 45% to 55%. 
     
     
         5 . A peripheral nerve growth conduit according to  claim 1 , further including poly-lactic acid (PLA), wherein the weight ratio of PCL:PLA is in the range 20:1 to 2:1. 
     
     
         6 . A peripheral nerve growth conduit according to  claim 1  wherein the conduit comprises at least 75 wt % PCL based on the total weight of the conduit. 
     
     
         7 . A peripheral nerve growth conduit according to  claim 1 , wherein the PCL has a number average molecular weight in the range 60,000 to 100,000 g/mol. 
     
     
         8 . A peripheral nerve growth conduit according to  claim 1 , wherein the conduit is a tubular conduit and the thickness of the conduit walls is in the range 20 μm to 80 μm. 
     
     
         9 . A peripheral nerve growth conduit according to  claim 1 , wherein the conduit has a length in the range 5 mm to 20 mm. 
     
     
         10 . A peripheral nerve growth conduit according to  claim 1 , wherein the conduit has a diameter in the range 1 to 5 mm. 
     
     
         11 . A peripheral nerve growth conduit according to  claim 1 , wherein the conduit is made from a film comprising PCL, preferably by solvent evaporation and optionally opposite edges of the film are joined together by heat sealing to form the conduit. 
     
     
         12 . A peripheral nerve growth conduit according to  claim 1 , wherein an inner (luminal) surface of the conduit has been treated with an alkaline composition, wherein preferably the duration of the treatment with alkaline composition is in the range 30 minutes to 3 hours, preferably the alkaline composition is aqueous NaOH, and preferably the concentration of the aqueous NaOH is in the range of 8N to 12N. 
     
     
         13 . A peripheral nerve growth conduit according to  claim 1 , wherein the inner (luminal) surface of the conduit includes —COOH and/or —OH terminated PCL chains, and preferably the conduit has nanopits on the inner luminal surface of the conduit. 
     
     
         14 . A peripheral nerve growth conduit according to  claim 1 , wherein the inner surface of the conduit has an average surface roughness (Ra) of at least 1 μm. 
     
     
         15 . A peripheral nerve growth conduit according to  claim 1 , wherein the surface roughness of the outer surface of the conduit has a an average surface roughness (Ra) of less than 1 μm. 
     
     
         16 . A peripheral nerve growth conduit according to  claim 1 , wherein the difference in average surface roughness between the inner (luminal) and outer surface is at least 1 μm. 
     
     
         17 . A peripheral nerve growth tubular conduit including poly-ε-caprolactone (PCL), the inner (luminal) surface of the conduit comprising pits (blind holes), the pits having an average diameter in the range 1-10 μm and an average depth in the range 1-6 μm, wherein the % surface coverage of the pits is in the range 30% to 70% the conduit comprises at least 50 wt % PCL based on the total weight of the conduit and the PCL has a number average molecular weight in the range 60,000 to 100,000 g/mol, and wherein the thickness of the conduit walls is in the range 10 μm to 80 μm, the conduit has a length in the range 5 mm to 50 mm and a diameter in the range 1 to 5 mm. 
     
     
         18 . A kit for treating a peripheral nerve in a human or animal, the kit including a peripheral nerve growth conduit according to  claim 1 . 
     
     
         19 . A method of treating a damaged peripheral nerve using a peripheral nerve growth conduit as defined in  claim 1 . 
     
     
         20 . A method of treating the surface of a peripheral nerve growth conduit according to  claim 1  with hydroxide, comprising the step of applying hydroxide to the surface. 
     
     
         21 . A method of making a peripheral nerve growth'conduit according to  claim 1 , the method comprising the step of:
 i) solvent casting a film including PCL, and allowing the solvent to evaporate.   
     
     
         22 . The method according to  claim 21 , further comprising the step of:
 ii) joining opposite edges of the film together by heat sealing to form the conduit.