diff --git a/connexion/decorators/parameter.py b/connexion/decorators/parameter.py
index c4a7a77e0..bcd61adf7 100644
--- a/connexion/decorators/parameter.py
+++ b/connexion/decorators/parameter.py
@@ -48,6 +48,17 @@ def snake_and_shadow(name):
     return snake
 
 
+def sanitized(name):
+    return name and re.sub('^[^a-zA-Z_]+', '',
+                           re.sub('[^0-9a-zA-Z_]', '',
+                                  re.sub(r'\[(?!])', '_', name)))
+
+
+def pythonic(name):
+    name = name and snake_and_shadow(name)
+    return sanitized(name)
+
+
 def parameter_to_arg(operation, function, pythonic_params=False,
                      pass_context_arg_name=None):
     """
@@ -65,13 +76,6 @@ def parameter_to_arg(operation, function, pythonic_params=False,
     """
     consumes = operation.consumes
 
-    def sanitized(name):
-        return name and re.sub('^[^a-zA-Z_]+', '', re.sub('[^0-9a-zA-Z[_]', '', re.sub(r'[\[]', '_', name)))
-
-    def pythonic(name):
-        name = name and snake_and_shadow(name)
-        return sanitized(name)
-
     sanitize = pythonic if pythonic_params else sanitized
     arguments, has_kwargs = inspect_function_arguments(function)
 
diff --git a/tests/decorators/test_parameter.py b/tests/decorators/test_parameter.py
index 990065dc5..269693bb7 100644
--- a/tests/decorators/test_parameter.py
+++ b/tests/decorators/test_parameter.py
@@ -1,6 +1,6 @@
 from unittest.mock import MagicMock
 
-from connexion.decorators.parameter import parameter_to_arg
+from connexion.decorators.parameter import parameter_to_arg, pythonic
 
 
 def test_injection():
@@ -25,3 +25,8 @@ def get_arguments(self, *args, **kwargs):
 
     parameter_to_arg(Op(), handler, pass_context_arg_name='framework_request_ctx')(request)
     func.assert_called_with(p1='123', framework_request_ctx=request.context)
+
+
+def test_pythonic_params():
+    assert pythonic('orderBy[eq]') == 'order_by_eq'
+    assert pythonic('ids[]') == 'ids'