Bone growth stimulators

Status: Decision completed

Policy context

Concerns about the safety and effectiveness regarding whether Bone Growth Stimulation provides equivalent or superior health outcomes compared to treatment without stimulators. Bone Growth Stimulation is the technique of promoting bone growth in difficult to heal fractures or in areas trying to be fused by applying a low electrical current or ultrasound to the fracture. The theoretical advantage of these devices is that they apply a direct electric current to the fracture 24 hours a day. A disadvantage of implantable and semi-implantable stimulators is that their implantation is a surgical procedure with attendant risks.

Primary criteria ranking

  • Safety = Low
  • Efficacy = High
  • Cost = Medium
Documents

Assessment timeline

  • Draft report published: July 10, 2009
  • Public comment period: July 10 - 24, 2009 
  • Final report published: July 31, 2009 
  • HTCC public meeting: August 28, 2009

Background

Bone Growth Stimulation is a technique of promoting bone growth in difficult to heal fractures or in areas trying to be fused by applying a low electrical current or ultrasound to the fracture. Fully implantable direct current stimulators are installed in a hospital under general or regional anesthesia. Both the stimulator and the power source are implanted. The surgeon makes an incision and places a spiral shaped cathode inside the bone. A wire leads to the power source and a small anode. The power source is a battery pack that is implanted in the nearby muscle. Partially implanted stimulators are cathode pins that are implanted at the edge of each bone that is fractured. Wires lead to the surface of the skin where a power source and the anode are located. Wires complete the circuit. The external portion of the device is held in place by a cast. This source of stimulation also runs continuously. Ultrasound stimulation is a device that generates low intensity pulses of sound and is applied to the skin over the fracture. Each method (electrical and ultrasound) must be used for at least three to six months to be effective. Questions about the effectiveness and durability of the treatment remain, as well as safety questions related especially to implanted techniques that carry attendant surgical risks.