diff --git a/tailbone/forms/core.py b/tailbone/forms/core.py
index 850768cf..c2398fdb 100644
--- a/tailbone/forms/core.py
+++ b/tailbone/forms/core.py
@@ -111,22 +111,14 @@ class CustomSchemaNode(SQLAlchemySchemaNode):
         for the given association proxy field name.  Typically this will refer
         to the "extension" model class.
         """
-        proxy = self.association_proxy(field)
-        if proxy:
-            proxy_target = self.inspector.get_property(proxy.target_collection)
-            if isinstance(proxy_target, orm.RelationshipProperty) and not proxy_target.uselist:
-                return proxy_target
+        return get_association_proxy_target(self.inspector, field)
 
     def association_proxy_column(self, field):
         """
         Returns the property on the proxy target class, for the column which is
         reflected by the proxy.
         """
-        proxy_target = self.association_proxy_target(field)
-        if proxy_target:
-            prop = proxy_target.mapper.get_property(field)
-            if isinstance(prop, orm.ColumnProperty) and isinstance(prop.columns[0], sa.Column):
-                return prop
+        return get_association_proxy_column(self.inspector, field)
 
     def supported_association_proxy(self, field):
         """