The Fitbone® intramedullary limb-lengthening system was developed in partnership with Dr. Rainer Baumgart, a world-famous specialist for intramedullary lengthening with more than 300 operations using this device and the most experienced surgeon in this field.

The product was launched in 1997. Since then, this innovative treatment concept has grown into a global success story with several thousand successful implants. The Fitbone TAA intramedullary lengthening system is intended for limb lengthening of the femur and tibia. With appropriate preoperative planning, it is possible to make axial and torsional corrections as part of limb lengthening.

The Fitbone® intramedullary limb-lengthening system is also compatible with the OrthoNext™ digital platform. The OrthoNext software features a reverse planning method module that simulates the target position, osteotomy level and blocking screw placement — enabling a more accurate preoperative assessment, optimized inventory sent to the OR, and, above all, optimized limb correction.

Benefits to Surgeon

  • Cutting-edge German engineering
  • Several thousand devices implanted since 1997
  • No over-reaming necessary
  • Accurate and controlled limb lengthening achieved with threefold visual and audible control feedback
  • Accidental retraction is not possible

Benefits to Patient

  • Comfortable lengthening process facilitated with the small, lightweight and silent Control Set
  • Reliable feedback from the system throughout the lengthening process
  • A small, light-weight Control Set
  • Quick reintegration into daily routines
  • Short hospitalization period
  • Minimal risk of infection
  • High product safety
  • Little scarring
  • “The potential advantages are many: fewer scars, improved aesthetics, better body image and psychological well-being, no irritation through pins and wires, reduced pain, uncommon infections, secondary axial deviation avoided, less joint stiffness, higher activity level during lengthening consolidation, faster rehabilitation, less risk of neurovascular compromise due to wire or screw insertion, and improvement in the ability to work during and after treatment.”1

Manufactured by WITTENSTEIN intens GmbH
Walter-Wittenstein-Strasse 1 – 97999 Igersheim (Germany)

Distributed by Orthofix
Orthofix declares that the contents are in conformity with the contents established by the manufacturer of Fitbone.


  • Fitbone TAA is an intramedullary lengthening system for limb lengthening of the femur and tibia.
  • Fitbone TAA intramedullary lengthening system is indicated for adult and pediatric (greater than 12 through 21 years of age) patients.


  • Patients with any open wounds or areas with poor soft tissue coverage near the operative site
  • Patients with an anatomic deformity that prevents the device from fitting
  • Patients with poor bone quality that would prevent adequate fixation of the device
  • Patients with compromised capacity for healing
  • Patients with metal allergies and sensitivities
  • Patients in which the implant would cross open epiphyseal growth plates
  • Blood supply limitations, peripheral vascular disease or evidence of inadequate vascularity
  • Insufficient intramedullary space that would lead to cortical weakening or vascular damage during an implantation
  • Patients with a body weight of over 100 kg for TAA11/13
  • Patients with a body weight of over 50 kg for for TAA09
  • Differences in leg length of less than 20 mm
  • No free access for proximal insertion of the intramedullary lengthening nail (e.g., coxa valga)
  • No reliable exclusion of bone infection
  • Expected non-compliance, mentally ill patient or patient with clouded consciousness
  • Pregnancy

In addition to the general risks involved in surgical intervention, the following side effects that might occur despite correctly performed treatment need to be mentioned:

  • Slight tingling sensation up to strong pain in the affected limb, especially during and after distraction
  • Temporary limited mobility of the affected limb


  1. Hasler CC, Krieg AH. Current concepts of leg lengthening. J Child Orthop. 2012;6:89-104