diff --git a/src/pixi/extras/Spine.js b/src/pixi/extras/Spine.js
index b275290..7bb29f8 100644
--- a/src/pixi/extras/Spine.js
+++ b/src/pixi/extras/Spine.js
@@ -882,7 +882,7 @@
 			lastTime = -1;
 		var frameIndex = (time >= frames[frames.length - 2] ? frames.length : spine.Animation.binarySearch(frames, time, 2)) - 2;
 		if (frames[frameIndex] < lastTime) return;
-		skeleton.bones[boneIndex].flipX = frames[frameIndex + 1] != 0;
+		skeleton.bones[this.boneIndex].flipX = frames[frameIndex + 1] != 0;
 	}
 };
 
@@ -910,7 +910,7 @@
 			lastTime = -1;
 		var frameIndex = (time >= frames[frames.length - 2] ? frames.length : spine.Animation.binarySearch(frames, time, 2)) - 2;
 		if (frames[frameIndex] < lastTime) return;
-		skeleton.bones[boneIndex].flipY = frames[frameIndex + 1] != 0;
+		skeleton.bones[this.boneIndex].flipY = frames[frameIndex + 1] != 0;
 	}
 };