Friday, October 23, 2020


Intraoperative Halo-femoral traction                           10-23-2020

As mentioned in the previous blog post, the use of halo-gravity traction (HGT) before surgery is a safe and very effective technique to improve severe spinal deformity, prior to a corrective surgical procedure.  On one end of the spine, the head, a carbon-fibre frame is placed onto the skull and a vertical force is placed on the spine via weights and pulleys.  On the other end is simply the patients’ body, so there is a limit as to how much weight we can apply without suspending the patients off the floor!  The other limitation for HGT is that, since body weight is used on the lower end, the spine deformity we are trying to correct cannot be too low, such as in the lumbar spine.  This is due to the fact there is less body weight below this area to pull against and hence hard to change the deformity as much when compared to deformities in the neck or chest (thoracic spine).


So, can we put a point of fixation below the area of spine deformity that will allow us to pull harder, before surgery?  The answer is yes, but the use of preoperative halo-femoral/pelvic/tibial traction has been shown to have an unacceptably high complication rate (1-3).  Despite this the technique has shown to be effective in preoperatively correcting coronal deformities (41-57%) and pelvic obliquity (up to 53%) (1-2). 


However, we can use this concept to help improve spinal deformity.  The place we can, and do, use this type of traction is in the operating room during the scoliosis correction surgery.  By using this method intraoperatively, one can avoid the problems associated with long-term traction yet gain the benefits of direct axial traction during the surgical procedure. 


Below is a patient, during surgery, with a 4-pin halo frame applied (green arrow), which is attached to a wire bale then to a rope (red arrow) which then goes to a weight.  This applied a pull in the direction of the red arrow.

On the opposite end (below), a pin is place across the femur just above the knee joint (green arrow) and is attached to a bale and rope which then pulls down (direction of red arrow). 

Both the halo frame and the traction pin in the femur are placed AFTER the patient is asleep under general anesthesia, and they are removed BEFORE the patient wakes up after surgery is completed.  Hence, there is no pain to the patient during the placement or removal of the halo or traction pin.


The next post will delve deeper into how we use this type of traction to improve our surgical outcomes.



1.     Bonnett C., Perry J., Brown J.C., et al:  Halo-femoral distraction and posterior spine fusion for paralytic scoliosis.  J Bone Joint Surg [Am] 54:202, 1972.

2.     Kane W.J., Moe J.H., Lai C.C.:  Halo-femoral pin distraction in the treatment of scoliosis.  J Bone Joint Surgery [Am] 49:1018-1019, 1967.

3.     Ransford A.O. Manning C.W.:  Complications of halo-pelvic distraction for scoliosis.  J Bone Joint Surg [Br] 57:131-138, 1975.