diff --git a/Assets/VRM10/Runtime/FastSpringBone/InputPorts/FastSpringBoneInstanceBuffers.cs b/Assets/VRM10/Runtime/FastSpringBone/InputPorts/FastSpringBoneInstanceBuffers.cs
index 9bf58b5f4..062922101 100644
--- a/Assets/VRM10/Runtime/FastSpringBone/InputPorts/FastSpringBoneInstanceBuffers.cs
+++ b/Assets/VRM10/Runtime/FastSpringBone/InputPorts/FastSpringBoneInstanceBuffers.cs
@@ -107,7 +107,7 @@ namespace UniVRM10.FastSpringBones.System
                         parentTransformIndex = parent != null ? transformIndexDictionary[parent] : -1,
                         currentTail = currentTail,
                         prevTail = currentTail,
-                        localRotation = joint.Transform.localRotation,
+                        localRotation = Quaternion.identity,
                         boneAxis = localChildPosition.normalized,
                         length = localChildPosition.magnitude
                     });