Complex hip replacement

The definition of a 'complex' hip replacement, as opposed to a 'standard' hip replacement, is the presence of any of a range of issues in a patient which may cause problems in the standard procedure and need to be planned for in advance to ensure a successful outcome for the patient.

Two specific issues that add significant complexity to a hip replacement procedure are obesity and morphological bone deformity:


Obesity is a risk factor for all surgery, with obese patients at higher risk of a number of complications including heart attack, peripheral nerve damage, wound healing problem and wound infection, and anaesthetic issues. Obesity also places more strain on joint replacement components and thereby increases wear and tear and shortens the life of the components.

Morphological bone deformity

Some people are born with different bone structures. One that affects hip replacement surgery is hip dysplasia, where the socket is slightly shallower than the ball and so increases the risk of hip dislocations. Another affecting the hip – which can be congenital (inherited) or caused by a previous bone fracture – is called coxa vara ad is where the femoral head (the ball at the upper end of the thigh bone) comes out of the femur at an unusual angle. It often causes the affected leg to be slightly shorter than the other one.

Other issues that must be taken into account ahead of a hip replacement fracture include:

  • Muscular issues (especially strength of gluteal muscles).
  • Skin conditions.
  • Bone conditions.
  • Neurological conditions.
  • Previous fractures.
  • Avascular necrosis (bone tissue death due to lack of blood supply).

All of these factors must be taken into account before proceeding with a hip replacement. Some conditions (or combination of conditions) may rule out a hip replacement or create an unacceptable level of risk to the patient. In other cases, these complexities can be planned for and of course make the procedure more difficult but ultimately feasible. Dr Moopanar always works very closely with his patients to explain in detail what the options are and what the risks are with any surgical procedure.

Where corrective surgery is required to a previous hip replacement – known as complex revision hip replacement – this is also classified as a complex hip replacement procedure.

Related Information

Hip replacement