Cemented vs uncemented hip replacement

A hip replacement works only if the components stay firmly attached to the bone. There are two ways to achieve that. Cement acts as a grout that fills the space between implant and bone, giving immediate stability. Uncemented components have a porous or hydroxyapatite-coated surface designed to encourage bone to grow into or onto it, which then holds the implant.

Both can last for many years. The questions are who they suit best and what happens in the early period, which is when the main differences in complications appear.

Cement gives instant fixation, so the person can usually put weight on the leg straight away. It is more forgiving in thin or soft bone and has a lower risk of a fracture around the implant in the first months. For older people and those with osteoporosis, this advantage is significant.

Disadvantages include the rare but serious reaction to cement, in which blood pressure drops during insertion (bone cement implantation syndrome), a risk that anaesthetists manage carefully. If a cemented stem later needs revision, removing cement can be more laborious.

Uncemented implants avoid cement and are widely used in younger, more active people with good bone, since the bone grows onto the implant and may maintain a strong long-term bond. They allow a more bone-preserving approach and, for some designs, easier revision.

The downsides include a higher risk of a fracture of the femur during or soon after surgery, particularly in older patients, and a small proportion of people have thigh pain in the first year. Fixation depends on the bone accepting the implant, so early weight bearing may be restricted for some designs.

Surgeons choose fixation by assessing bone quality on X-ray, age, general health, the reason for surgery and the implant's registry track record. In older people, many UK surgeons favour cemented stems, and NICE guidance on hip fracture (CG124) recommends cemented implants where hip replacement or hemiarthroplasty is used. In younger people with strong bone, uncemented or hybrid fixation is widely used.

The National Joint Registry publishes implant and fixation-level data, and many surgeons choose a combination that has well-documented results rather than something new.

• Aged over about 70, thin bone or after a hip fracture: a cemented stem is commonly advised.

• Younger, active and good bone quality: uncemented or hybrid fixation is often considered.

• Osteoporosis or taking long-term steroids: bone strength matters, and cement may be safer.

• Heart or lung disease: tell the anaesthetist, since cement insertion has circulatory effects they manage.

• Wanting information on implant performance: ask for the implant's National Joint Registry data.

Cement is not "glue that wears out" in the way many assume; cemented stems can last for decades. And uncemented is not automatically more modern or better; it suits certain bones. Also, a hybrid is not an unusual compromise; it is common in registry data.

The choice is mostly the surgeon's, based on your bone, and a patient preference for one or the other should be weighed against safety.

• Which fixation do you recommend for my bone and why?

• What is the registry track record of the implant you plan to use?

• How soon can I put weight on the leg?

• What are the risks of fracture or other complications with this choice?