How to set orientation of Bone3d* in world space instead of local space?

I have a 3d model of a human skeleton.

Currently I do the following:

Bone3D* node; //The bone I want to set the orientation of.
Mat4 mat = node->getLocalMat(); //I modified Skeleton3d to let me access the local matrix
Vec3 pos, scale;
// store original translation & scale
mat.getTranslation(&pos);
mat.getScale(&scale);
// reset matrix
mat.setIdentity();

// create float array for translation
float trans[3];
trans[0] = pos.x;
trans[1] = pos.y;
trans[2] = pos.z;

// create float array for scale
float s[3];
s[0] = scale.x;
s[1] = scale.y;
s[2] = scale.z;

// create quaternion float array for rotation
Quaternion q = ToQuaternion(yaw,pitch,roll);

float rot[4];
rot[0] = q.x;
rot[1] = q.y;
rot[2] = q.z;
rot[3] = q.w;

// send transform values to bone
node->setAnimationValue(trans, rot, s);

By doing this, I am able to set the angle of the bone relative to its parent bone (similar to how localspace works with 2d sprites), but I am not able to set the orientation of the bone in 3d space. How can I do that ? I still want the location of the bone to be where it should be (it should be attached to its parent at the correct place), but I want to be able to set its yaw, pitch and roll, relative to the world.