Osseointegration

What is osseointegration?

Osseointegration is a procedure in which a metal implant is fitted into the intramedullary canal of a residual bone. This implant serves as an anchor-point for an external prosthesis and enables direct loading through the skeleton, rather than weightbearing on soft tissue as is the case with traditional socket prostheses.

Indications and contraindications for osseointegration

Osseointegration is typically employed to address: 

Mobilisation issues in people with limb loss: as an alternative to traditional socket prostheses.

Complication reduction in existing socket prosthetic users: including those with secondary joint pain, skin breakdown, dramatic volume issues resulting in poor fit, or neuroma formation which increase socket avoidance.

Restoration of alignment: where it is neccessary to restore normal anatomical alignment through the bone to help reduce the risk of developing degenerative joint problems such as arthritis.

Digital amputation: where amputation has resulted in partial finger loss.

Contraindications for osseointegration include: 

Poor bone quality.

Active infection.

Historic radiation therapy resulting in impaired bone healing.

Poorly managed health conditions, including diabetes, bleeding disorders or poor cardiovascular health.

Psychological factors which reduce the probabilty of clinical compliance.

Benefits and complications of osseointegration

Benefits

  • Prof. Al Muderis’ Osseointegrated Prosthetic Limb (OPL) allows for natural loading of the joint and bone.
  • Allows for a more natural and stable gait, and less physical exertion, when mobilising.
  • Avoids the need for liners and socks of the type required with socket prosthetics.
  • Enables osseoperception through the bone, permitting distinction between surface types and environmental stimuli.
  • Avoids the painful symptoms associated with socket prosthetic use.
  • Allows for a much wider range of activities than socket prostheses.
  • Facilitates the development of muscular strength in the residual limb.
 
Known complications
 
  • Post-operative infection
  • Deep vein thrombosis (DVT) and pulmonary embolism.
  • Failure or loosening of the implant, requiring revision. 
  • Vascular injury and bleeding.
  • Periprosthetic fracture.
  • Fluid leakage
  • Negative psychological outcomes. 
  • Neuropathic pain.

The surgery

Preparation prior to surgery

  • You will receive a thorough health assessment: including medical history. You may be advised to modify certain lifestyle factors and you may be referred to another specialist. You may be asked to stop taking certain medications as your surgery date approaches. X-rays, CT scans, and MRIs will be used to evaluate your condition and plan your surgery.  
  • Skin and bowel preparation: On the evening before your surgery, you will be asked to wash your leg using the sponge provided at your pre-admission clinic. A skin test may be administered if an iodine allergy is suspected. You will also be provided medicine to help you evacuate your bowels prior to surgery.
  • Patient education: if neccessary, you may speak with a physiotherapist who can advise you on post-operative mobility.

On the day of the surgery

  • You will be asked to complete your surgical paperwork and will meet with the anaesthetist.
  • The surgical site will be prepared.
  • You will be administered general or spinal anaesthesia.
  • The soft tissue is managed, and excess skin and soft tissue fat are removed to minimise the bone-to-skin distance. The muscle groups are rearranged to optimise functional use of the leg, and the soft tissue facial layer is reorganised around the stem to enhance overall stability and reduce complications.
  • The bone residuum is reshaped, and any bone spurs are removed.
  • The bone canal is prepared using a specialised instrument. The internal component of the implant is press-fit into the bone canal.
  • Any neuromas are excised. Existing nerves will be repositioned deep within the muscle group to minimise future complications.
  • The stump is refashioned for cosmetic purposes.
  • A circular opening is created through the skin at the base of the residual limb, known as the stoma, through which the internal part of the implant connects to the external part and the prosthesis.

After your surgery

  • Wound care: It is important that you monitor your wound for signs of infection, and follow a strict hygeine regime to reduce the risk thereof. You may clean the wound gently with warm water and soap, being careful to dry it thoroughly. 
  • Pain and swelling: You may experience mild to moderate pain in the implanted limb. You will be prescribed painkillers to manage these symptoms. Inflammation can be controlled by icing (15 minutes per hour maximum) during the first week.
  • Mobilising: Partial weight-bearing and fitting of the lower prosthesis can commence within a few days after surgery and rehabilitation and gait training can begin. You will begin to load the implant according to a fast or slow loading program, which gradually increases the amount of force exerted on the implant over a fixed period. This continues until you can exert a downward force of 50kg or a force equivalent to half your own bodyweight. For the first 12 weeks after surgery, you will be required to mobilise using crutches. You must avoid excessive rotation, pivoting and twisting during your recovery. 
  • Aftercare: after 6 weeks, you will be asked to complete further X-rays to assess healing, and at three, six and twelve months after your surgery for the same reason. You may be prescribed blood thinners to reduce the risk of a clot developing. 

Concerns

If you are concerned about your pain level, or develop significant bleeding, fever or redness around the surgical site, please contact us immediately. For after-hours support, contact the hospital at which your surgery was completed. They will contact Prof. Al Muderis on your behalf.

Norwest Private Hospital: (02) 8882 8882

Macquarie University Hospital: (02) 9812 3000