Fitbone is a modern fully internal motorized lengthening nail system that is implanted inside the bone and allows controlled limb lengthening from within. There are no external fixators, pins, or metal parts visible on the outside. The lengthening process is performed through a small receiver placed under the skin and a remote control used from outside the body.

Thanks to its comfort, aesthetic appearance and minimal impact on daily life, the Fitbone system is one of the leading internal lengthening options.

How Does the Fitbone System Work?

During surgery, the bone is cut in a controlled way (osteotomy) and a telescopic motorized intramedullary nail is inserted into the medullary canal. A small receiver is placed under the skin close to the nail tip.

This receiver:

• Is not noticeable from the outside,
• Remains invisible under clothing in daily life,
• Does not significantly disturb the patient when it is planned and positioned correctly.

Daily lengthening is performed by bringing the external remote control close to the area where the receiver is located. The remote sends a signal to the receiver, which activates the motor inside the nail and gently separates the bone ends by fractions of a millimetre. The process is quiet, controlled and usually only mildly painful, if at all.

Who Is a Suitable Candidate for Fitbone?

The Fitbone method is a strong option especially for patients with high aesthetic expectations who do not want to carry an external fixator. Typical candidates are:

• People who want limb lengthening with a focus on comfort and aesthetics,
• Patients who do not want their daily life restricted by an external frame,
• Those who prefer internal (intramedullary nail) methods,
• Adult patients whose bone structure is suitable for an internal nail,
• Patients who can follow a daily distraction schedule in a disciplined and regular way.

The most appropriate method for each patient is determined after a detailed clinical examination, planning, X-rays and, when necessary, advanced imaging. In some patients Fitbone is chosen alone; in others it is compared with alternative techniques and decided on an individual basis.

How Much Lengthening Is Possible with Fitbone?

Depending on the pre-operative plan and the tolerance of the bone and soft tissues, Fitbone typically allows:

• Femur (thigh bone): Up to about 8 cm,
• Tibia (shin bone): Up to about 5 cm.

When deciding on the target length, muscles, tendons, nerves and the patient’s current height are all evaluated together. The aim is not only to gain centimetres, but to achieve a balanced, healthy and functional lower limb in the long term.

Surgical Process and Recovery

Surgical Stage

Fitbone surgery is a planned and controlled operation performed by an experienced team. In general:

• Surgery time is around 2–2.5 hours,
• The bone is cut through a controlled osteotomy,
• The motorized nail is inserted into the medullary canal,
• The small receiver is placed under the skin,
• All incisions are closed with an aesthetic suturing technique.

Most patients are mobilised with support in the early post-operative period according to the surgeon’s instructions. Thanks to the internal nail system, daily life is usually more comfortable compared with external fixator methods.

Distraction (Lengthening) Phase

The distraction phase usually starts about 5–7 days after surgery. During this period:

• Average lengthening is 0.75–1 mm per day,
• Lengthening is performed by bringing the external remote close to the receiver area,
• Pain during the procedure is generally minimal,
• Your doctor regularly monitors bone healing and alignment on X-rays and adjusts the plan if needed.

Physiotherapy and Rehabilitation

As with all limb lengthening procedures, physiotherapy is indispensable in the Fitbone method. While muscles and soft tissues adapt to the lengthened bone, the rehabilitation programme focuses on:

• Maintaining joint range of motion,
• Strengthening the muscles,
• Balance and gait training.

A well-planned rehabilitation programme greatly improves both the lengthening outcome and long-term functional results.

Advantages of the Fitbone Method

The main advantages of the Fitbone method can be summarised as follows:

• Fully internal system: There is no external frame or rod, which provides significant comfort in daily life and a better cosmetic appearance.
• Aesthetic look: After surgery, no metal structure is visible under clothing.
• Lower infection risk: Compared with external fixator techniques, skin and soft-tissue problems are less common.
• Controlled and precise lengthening: The motorised system allows the rate and amount of distraction to be adjusted very accurately.
• More comfortable rehabilitation: Using an internal nail often makes the rehabilitation phase more comfortable for many patients.
• Mid-range cost option: It is more expensive than the LON method, but relatively more affordable than the Precice 2 system.

Why Might You Prefer the Fitbone Method?

If you are looking for both a safe surgical technique and a comfortable recovery period in your limb lengthening journey, the Fitbone internal lengthening system offers a strong and modern alternative.

It is especially suitable for patients who:

• Do not want to carry an external fixator,
• Care about freedom of movement in daily life,
• Prefer minimal visible scars and metalwork,
• Want to evaluate options such as LON and Precice 2 objectively together with their surgeon.

The decision on which method is best for you should be made after a thorough consultation, radiological evaluation and a clear discussion of your expectations. As with all limb lengthening techniques, the ultimate goal with Fitbone is not only to gain centimetres, but to achieve a safe, well-balanced and healthy long-term result.