Overview

Bone loss, deficits, gaps, or non-unions are areas of missing bone that need to be healed with the help of a bone transport or vascularized membrane procedure. These surgeries can be performed using internal or external technology offered at the Canadian Limb Lengthening Centre. When bone is broken, it heals by first forming a callous (which is new bone that is still soft but will harden over time). Bone transporting uses this process of callous formation (or healing new bone) and stretches it gradually (a process called distraction osteogenesis) to fill the space where bone is missing. This is done using fixation devices that slowing stretch the new forming bone in order to make it long enough to fill the gap. Bone transport techniques can be used to fill very large bony defects (or gaps), anywhere from 2-16 or more centimeters.

Indications / Candidacy

Patients who require bone transport are usually missing a section of bone due to infection, trauma or disease. If a patient has undergone a serious injury or had bone infections, there may be a gap or empty void left in their bone. Candidates will be assessed by one of our surgical specialists to ensure a proper diagnosis and that all physical criteria for surgery are met.

Good candidates for this surgery may have:

  • Segmental bone loss
  • Bone loss as a result of fractures, tumour resection or extensive debridement for bone infection
  • Bone non-unions (broken bone that has failed to heal)

Treated Conditions

The Canadian Limb Lengthening Center offers treatment of many complex orthopedic conditions. We pride ourselves in providing highly specialized expert care and the most up to date equipment and technologies. Using a holistic approach to acute deformity correction, we help patients treat many of the following conditions:

Condition

Bone defect

Condition

Charcot foot

Condition

Mal-union

Condition

Non-union and infected non-unions

Condition

Osteomyelitis

Surgical Technique

Bone transport with external fixation (standard and with cables)

To perform bone transport with an external fixation device, your surgeon will make a cut at one end of the bone to create a movable transport bone. All bone segments are attached to a circular external fixator with special bone screws, wires or cables. Adjustments are then made externally to the fixator to move the transport segment along the space where bone formation is needed. Once the length of the gap has been filled with new bone, the consolidation phase starts, during which the bone must heal and harden before the external fixator can be removed.

An external fixator can be thought of as a frame that is surgically attached to the bone. The fixator remains on the outside of the limb while the screws or wires that attach the apparatus to the bone are passed through the skin. Some external devices have a pully and cable system that is used to transport the middle segment of bone from one end of the bone gap to the other.

Bone transport with internal fixation (called PABST – plate assisted bone segment transport)

During bone transport with internal fixation a plate is attached to both the proximal and distal portions of the bone using screws. The bone is then cut to create a transport bone that will be moved from one end of the bone gap to the other 1. A specialized magnetic lengthening nail is then placed through the inside of the bone and locked with bolts on both the transport bone and the stable portion of the bone2. The bone transport is then started after 7-10days, allowing the bone break to create a callous (new bone formation) which will then be stretched gradually using the magnetic interaction between the special nail and an external remote controller (ERC)3.

Images, courtesy of The National Center for Biotechnology, part of National Library of Medicine, www.ncbi.nlm.nih.gov

Masquelet technique (or vascularized membrane technique)

The Masquelet procedure is used to fill large bone gaps using a cement bone spacer that temporarily fills the space. Over the course of the next 6 weeks a vascularized membrane forms around the cement. This tissue forms small blood vessels and secretes proteins that promote bone formation. During a second surgery the cement is removed and replaced with a bone graft taken from another part of the body. This technique also requires some form of bony fixation with either external or internal fixation, or both to allow stability of the limb while the bone graft heals.

Results

Historically, due to the difficulty in managing segmental long bone defects, amputation would have been the preferred treatment for many of our patients. With advances in technology offered at the CLLC we provide patients treatment techniques to manage bone loss, bony deficits and gaps, and non-unions. Some of these techniques have reduced treatment time and complications and facilitate normal daily life during the treatment course. With the ability to regenerate bone defects greater than 10cm, patients typically live very active, healthy lives after surgery. Bone transport can increase function, improve muscle strength, and decrease discomfort for our patients. A variety of psychological benefits are also experienced as a result of having a limb reconstruction solution instead of an amputation.

Potential Complications

As with any surgical procedure, bone transports can have difficulties and complications. We take extensive measures to avoid complications and have experienced specialist who know how to respond in cases where difficulties arise. In most cases, the problems may be addressed such that the end result, or outcome, is not compromised. Complications and side effects may include:

  • Delayed union, non-union or malunion of the bone
  • Superficial (skin and soft tissues) or deep infection (bone infection)
  • Neurovascular injury (very rare)
  • Compartment syndrome (very rare)
  • Pin tract infection
  • Joint stiffness
  • Axial deviation
  • Soft tissue incarceration

Pre-Operative Care

  • An extensive medical history will be taken during your initial assessments
  • It is recommended that you stay active, eat a healthy diet, and stop smoking prior to any operation
  • Certain medications and vitamins may need to be stopped several weeks before
  • Discuss all medications and over the counter drugs with your surgeon
  • Use a calendar or agenda to organize your pre- and post-op appointment dates
  • Make arrangements for personal care givers

Post-Operative Care

  • Patients can expect to be hospitalized for 24-48hrs after the surgery
  • Toe touch or no weight bearing during the bone transport time. Weight bearing will be increased during consolidation phase (bony healing)
  • 7-14 day latency period (to allow the callous new bone to form around the bone break)
  • 0.25mm distraction 3-4x per day (Protocol may vary depending on patient’s needs)
  • The dressings are changed in the hospital on post-operative day 1 or 2 and then kept until the first clinic visit
  • Seven to ten days after surgery there is the first follow-up

Patients who will undergo this procedure should read:

For External Fixation

External fixator Immediate post-operative care
Struts adjustments
Pin site care and infection protocol

For internal fixation

Immediate post-operative care
ERC magnet instructions for lengthening

Follow-ups after surgery

  • Patients will be required to attend all post-operative appointments
  • Radiographic evaluation is conducted every 2 weeks during the bone transport period
  • There will be monthly follow ups during the consolidation phase
  • Speed of bone transport will be adjusted according to progress of bony regeneration on radiographs
  • Physiotherapy session will focus on mobilisations of surrounding joints

Case studies

50 year old man with fracture of tibia
18 year old with open fracture with bone loss

AM I A CANDIDATE?

Are you experiencing an orthopedic condition and would like to improve your physical capabilities?

Or you simply would like to achieve your long-lasting dream of improving your height?

Let us help you achieve your optimal health and wellness in a professional setting.

Let’s open up a discussion to help you achieve your goals.

Highly specialized expert care at CLLC

At the Canadian Limb Lengthening Centre we offer complex deformity correction and limb lengthening surgeries performed by experienced surgeons with the most up to date technologies. When it comes to your care, and treatment of deformity and limb length discrepancy, our surgeons have extensive training and experience.

LW