diff --git a/Assets/VRM10/Runtime/Components/Vrm10Instance/Vrm10Instance.cs b/Assets/VRM10/Runtime/Components/Vrm10Instance/Vrm10Instance.cs
index cc2355991..2be908386 100644
--- a/Assets/VRM10/Runtime/Components/Vrm10Instance/Vrm10Instance.cs
+++ b/Assets/VRM10/Runtime/Components/Vrm10Instance/Vrm10Instance.cs
@@ -57,17 +57,16 @@ namespace UniVRM10
 
         Vrm10InstanceRuntime m_runtime;
 
-        /// <summary>
-        /// delay new Vrm10InstanceRuntime
-        /// </summary>
-        /// <returns></returns>
-        Vrm10InstanceRuntime GetOrCreate()
+        public Vrm10InstanceRuntime Runtime
         {
-            if (m_runtime == null)
+            get
             {
-                m_runtime = new Vrm10InstanceRuntime(this);
+                if (m_runtime == null)
+                {
+                    m_runtime = new Vrm10InstanceRuntime(this);
+                }
+                return m_runtime;
             }
-            return m_runtime;
         }
 
         void Start()
@@ -85,7 +84,7 @@ namespace UniVRM10
         {
             if (UpdateType == UpdateTypes.Update)
             {
-                GetOrCreate().Process();
+                Runtime.Process();
             }
         }
 
@@ -93,13 +92,13 @@ namespace UniVRM10
         {
             if (UpdateType == UpdateTypes.LateUpdate)
             {
-                GetOrCreate().Process();
+                Runtime.Process();
             }
         }
 
         private void OnDestroy()
         {
-            GetOrCreate().Dispose();
+            Runtime.Dispose();
         }
     }
 }
diff --git a/Assets/VRM10/Runtime/Components/Vrm10Instance/Vrm10InstanceRuntime.cs b/Assets/VRM10/Runtime/Components/Vrm10Instance/Vrm10InstanceRuntime.cs
index a7591ebf0..7fad226ad 100644
--- a/Assets/VRM10/Runtime/Components/Vrm10Instance/Vrm10InstanceRuntime.cs
+++ b/Assets/VRM10/Runtime/Components/Vrm10Instance/Vrm10InstanceRuntime.cs
@@ -15,7 +15,8 @@ namespace UniVRM10
         private readonly VRM10Constraint[] m_constraints;
         private readonly Transform m_head;
         private readonly FastSpringBoneService m_fastSpringBoneService;
-        private readonly FastSpringBoneBuffer m_fastSpringBoneBuffer;
+
+        private FastSpringBoneBuffer m_fastSpringBoneBuffer;
 
         public Vrm10InstanceRuntime(Vrm10Instance target)
         {
@@ -46,6 +47,20 @@ namespace UniVRM10
             m_fastSpringBoneService.BufferCombiner.Register(m_fastSpringBoneBuffer);
         }
 
+        /// <summary>
+        /// このVRMに紐づくSpringBone関連のバッファを再構築する
+        /// ランタイム実行時にSpringBoneに対して変更を行いたいときは、このメソッドを明示的に呼ぶ必要がある
+        /// </summary>
+        public void ReconstructSpringBone()
+        {
+            m_fastSpringBoneService.BufferCombiner.Unregister(m_fastSpringBoneBuffer);
+
+            m_fastSpringBoneBuffer.Dispose();
+            m_fastSpringBoneBuffer = CreateFastSpringBoneBuffer(m_target.SpringBone);
+
+            m_fastSpringBoneService.BufferCombiner.Register(m_fastSpringBoneBuffer);
+        }
+
         private FastSpringBoneBuffer CreateFastSpringBoneBuffer(Vrm10InstanceSpringBone springBone)
         {
             return new FastSpringBoneBuffer(