Stature lengthening is the surgical gradual lengthening of the long bones of the legs, with the goal of increasing a person’s height.
This is achieved by placing an implant inside the bone after carefully cutting it, and then gradually (about 1 mm per day) moving the two pieces of bone apart so that new bone grows in the gap and the bone becomes longer.
Historically this was done with external fixation, involving a metal frame around the leg and wires running through skin and into bone. Recent technology allows this to be done with specialised rods, known as “intramedullary motorized nails” that are implanted inside the bone.
Once a patient has surgery to cut the bone and implant the nail, they return home with a specialized transceiver which is used to activate the nail on a daily basis, achieving an incremental amount of length each time. They hold the transceiver over a predetermined part of the leg, and each time they do this the leg lengthens by as little as 0.18 mm – less than the thickness of a sheet of copy paper.
By doing this gradually, several times per day, bone grows in the gap between the two cut ends of the bone. Once the lengthening is complete, the bone becomes as solid as normal bone, and the nail can be removed.
This procedure is undertaken commonly in conditions where one leg is much shorter than the other. It can be performed on the tibia (shinbone), or femur (thigh bone). Most people who undergo stature lengthening will have either both femurs lengthened, or both femurs and both tibias.
It is important in stature lengthening to aim for perfect limb alignment. If there are alignment problems prior to surgery, it may be possible to address these at the same time.
Who can have Stature Lengthening?
After careful consideration of the literature and the practice of international colleagues, A/Prof Leo Donnan and Dr Stewart Morrison will consider stature lengthening for people who:
- Are under the 10th centile for height, for their sex;
- For men this means under 167 cm (5’4”)
- For women this means under 155 cm (5’1”)
- Are under a Body Mass Index (BMI) of 35;
- Do not have arthritis present in any of the joints of their lower limbs;
- Undergo an assessment by a psychiatrist in order to exclude signs of BDD;
- Agree to the upfront fees as listed;
- Undertake the prescribed pre-operative physical therapy program;
- Provide informed consent, included but not limited to acknowledgement of the risks of limb lengthening surgery (including infection, scarring, requirement for re-operation, pulmonary embolus, fat embolus, nerve injury, amputation, and death); and
- Agree that no certain amount of length is guaranteed, and the final result may be less than the planned amount.
How much height can I get?
While lengthening technology and surgical technique are very reliable, lengthening relies on the body’s ability to generate bone and the ability of joints, muscles, and tendons to stretch appropriately.
The femur can be lengthened up to 8 cm, and the Tibia (shin bone) up to 5 cm. This means, if lengthening is performed in both segments, up to 13 cm (5 inches) of additional height is possible.
This is “best case scenario” and an individual assessment of your possible height increase will be provided by your surgeon.
Will Insurance Pay?
Limb lengthening performed for a limb length difference (one leg is shorter than the other) or in cases where a person has a bone dysplasia causing their short stature, surgery costs will be covered by Medicare and a person’s private health insurance but there are out of pocket expenses that would be defined with financial consent.
Stature lengthening in the absence of a bone dysplasia or proven genetic condition, is considered a ‘cosmetic’ procedure, and will not be covered by Medicare or Private Health Insurance. A patient must pay all costs.
What Devices or Implants are used?
Historically, Limb lengthening was performed with external fixation, metal rings on the outside of the leg connected to the bone by wires running through the skin. Fully internal motorized nails have revolutionised limb lengthening surgery.
An intramedullary motorized nail is implanted inside the bone. The nail is ‘telescopic’ in design, like an old-fashioned car aerial (or telescope!) and can be controlled to extend gradually. The device is activated by a transceiver that is held over the outside of the limb. These devices are highly specialised, and have many intricate internal components.
There are two intramedullary motorised nails available currently, and their proprietary (brand) names are as follows:
- The PRECICE nail, manufactured by NuVasive Inc. (San Diego, CA, USA)
The PRECICE nail has a magnet inside it, nestled inside a spindle. The transceiver that is used to activate the nail from the outside uses a pair of electromagnets.
- The FITBONE nail, manufactured by Orthofix (TX, USA)
The FITBONE nail has a small cable extending from its end, which attaches to a small receiving that sits under the skin, about the size of a twenty cent coin. The transceiver is placed against this area of skin, in order to activate the nail and achieve incrememental lengthening.
Each of these nails comes in a range of length and widths, each with a different maximal lengthening capacity. A/Prof Donnan and Dr Morrison both have experience in the implantation and use of both of these devices. They will select the device that is the best fit for your individual situation.
Note that a previously produced device, the NuVasive STRYDE Nail, is no longer available on the market.