If you have been advised to undergo a total hip replacement, you may understand why the surgery is needed but still wonder what actually happens during the operation.
A total hip replacement involves removing the damaged surfaces of the hip joint and replacing them with artificial components. The damaged ball of the hip is replaced with an artificial femoral component, while the damaged socket is replaced with an artificial acetabular component.
If you are preparing for hip replacement surgery, understanding the procedure step by step can make the surgical process easier to follow and help you know what to expect before, during and immediately after the operation.
What exactly is replaced in a total hip replacement?
The hip is a ball-and-socket joint. The ball is the rounded upper end of the thigh bone, called the femoral head. It fits into the socket, known as the acetabulum, which forms part of the pelvis.
In conditions such as advanced osteoarthritis, the cartilage covering these surfaces can become severely damaged. This can lead to pain, stiffness and difficulty moving the joint. During a total hip replacement, both sides of the joint are replaced:
- Femoral component: replaces the damaged femoral head and includes a stem that fits into the thigh bone.
- Acetabular component: replaces the damaged socket and forms the new artificial cup.
- Ball: attaches to the femoral stem and fits inside the new socket.
- Liner: sits inside the artificial socket and provides the bearing surface for the new ball.
Step 1: Pre-surgery assessment and preparation
Before the operation, the surgical and anaesthesia teams review your medical history, medications and general health to make sure you are appropriately prepared for surgery.
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
You may undergo tests such as blood tests, an electrocardiogram, urine testing or imaging, depending on your health and the requirements of the surgical team.
The team will also confirm the surgical plan, discuss the anaesthetic and review any medicines that need to be adjusted before the operation. On the day of surgery, the surgical site is checked and marked so that the correct hip is operated on.
Step 2: Anaesthesia is given
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
Total hip replacement can be performed using either spinal anaesthesia or general anaesthesia, depending on your health, the surgical plan and the anaesthetist's assessment.
With spinal anaesthesia, an injection is given in the lower back to numb the lower part of the body. Sedation may also be given to help you relax or sleep during the procedure. With general anaesthesia, you are unconscious throughout the operation.
Step 3: The surgeon reaches the hip joint
Once the anaesthesia has taken effect, the surgical team prepares the skin and covers the area with sterile drapes. The surgeon then makes an incision to reach the hip joint. The exact location and length of the incision depend on the surgical approach and the patient's anatomy.
Several surgical approaches can be used for total hip replacement. These include approaches through the front, side or back of the hip. The choice depends on factors such as the surgeon's experience, the patient's anatomy and the specific circumstances of the operation.
Step 4: The damaged femoral head is removed
The surgeon carefully exposes the hip joint and separates the femoral head from the socket. The damaged femoral head is then cut away and removed. This creates access to the upper part of the femur, where the new femoral component will be positioned.
Step 5: The thigh bone is prepared
The inside of the upper femur is prepared so that it can accommodate the stem of the artificial femoral component. The surgeon shapes the bone to achieve an appropriate fit for the selected implant. The goal is to establish stable positioning and restore the appropriate relationship between the femur and the pelvis.
The stem may be fixed using bone cement or may be designed to achieve biological fixation, allowing bone to grow onto or into a specially prepared implant surface. The choice depends on the implant, bone quality and individual circumstances.
Step 6: The natural socket is prepared
The damaged cartilage and bone from the surface of the acetabulum are removed and the socket is carefully shaped. This creates a prepared surface into which the artificial acetabular component can be placed.
The surgeon aims to position the socket component at an appropriate angle and depth so that the new hip can move properly and remain stable.
Step 7: The artificial socket is inserted
The artificial acetabular cup is positioned inside the prepared socket. Depending on the implant system, the component may be press-fitted into the bone or secured using another fixation method. A liner is then placed inside the cup to create the bearing surface for the new artificial ball.
The materials used can vary. Modern implants may use combinations of metal, ceramic and highly durable medical-grade plastic.
Step 8: The new femoral component is positioned
The artificial femoral stem is placed inside the prepared femur. A new ball is attached to the top of the stem. The size and position of the components are selected to help restore appropriate hip mechanics, leg length and stability.
Depending on the implant design and surgical technique, the femoral component may be cemented or fixed without cement.
Step 9: The surgeon tests the new hip
Before closing the incision, the surgeon moves the artificial hip through a range of positions and checks its stability and movement.
The team also assesses factors such as the relationship between the components, leg length and the overall function of the new joint. If necessary, component sizes or positioning can be adjusted before the final implants are secured.
Step 10: The incision is closed
Once the surgeon is satisfied with the position and stability of the replacement, the surrounding tissues are repaired and the incision is closed.
Stitches, clips or other closure methods may be used depending on the surgical technique. A sterile dressing is then placed over the wound.
How long does total hip replacement surgery take?
A total hip replacement generally takes around 1 to 2 hours, although the exact duration varies from patient to patient. The operation may take longer when the hip is severely damaged, when there has been previous surgery or when the surgical team encounters factors that require additional work.
The time spent in the operating department is longer than the actual surgical procedure because preparation, anaesthesia and recovery-room monitoring are also required.
What happens immediately after the operation?
After surgery, you are taken to a recovery area where your vital signs and recovery from anaesthesia are monitored. Pain-relieving medicines are provided, and the medical team monitors the surgical wound and your overall condition.
Once you are sufficiently recovered, you are transferred to the appropriate ward or discharge area. Physiotherapy usually begins early. You may be helped to stand and walk with crutches or a walking frame as soon as it is considered safe.
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
When can you start walking after total hip replacement?
Many patients are encouraged to begin moving and walking shortly after surgery, often with assistance from a physiotherapist. Early movement is part of modern hip replacement recovery and helps patients regain mobility and strength.
The amount of weight you can put through the operated leg and the exercises recommended will depend on your surgery and the instructions of your treating team.
Walking ability gradually improves as pain decreases, the wound heals and the muscles around the hip become stronger.
What happens to the artificial hip after surgery?
The artificial components become the new bearing surfaces of the hip. Depending on how the implants are fixed, the bone may directly attach to the implant or the component may be secured using bone cement.
Over time, the surrounding tissues heal and the muscles supporting the hip become stronger. The artificial joint is designed to provide a stable, functional replacement for the damaged natural joint, although it does not reproduce every aspect of a normal biological hip.
Does total hip replacement involve removing the whole hip?
No. Despite the name “total hip replacement,” the operation does not mean that the entire hip area is removed. The damaged joint surfaces are removed and replaced. The rest of the surrounding bones and soft tissues are preserved as much as possible.
What is the difference between total and partial hip replacement during surgery?
The main difference is what happens to the socket. In a total hip replacement, both the femoral head and the acetabular surface are replaced.
In a partial hip replacement, the damaged femoral head is replaced but the patient's natural socket remains in place. The two procedures are used for different clinical situations, so the choice depends on the underlying condition and individual circumstances.
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
What determines the type of implant used?
There is no single implant that is appropriate for every patient. The surgical team considers factors such as bone quality, age, activity level, anatomy, underlying condition and the type of fixation planned.
Implant components may differ in material, design and fixation method. The surgeon selects the combination considered appropriate for the individual's anatomy and clinical needs.
What should you expect during the first days after surgery?
The early recovery period focuses on pain control, safe movement, wound care and prevention of complications. You may initially need a walking frame or crutches. A physiotherapist can teach you exercises and techniques for getting in and out of bed, walking and managing everyday activities safely.
If recovery is uncomplicated and you are medically fit, some patients can leave hospital within a few days. Others may need a longer stay depending on their health, mobility and support at home.
The Bottom Line
Total hip replacement involves carefully replacing the damaged surfaces of the hip joint with artificial components. The surgeon removes the damaged femoral head, prepares the thigh bone and socket, positions the new femoral and acetabular components, and checks the movement and stability of the new joint before closing the incision.
The operation generally takes around 1–2 hours, although the complete time in the operating department is longer because it includes anaesthesia, preparation and immediate recovery.
After surgery, early movement and physiotherapy are important parts of recovery. The exact surgical technique, implant design, fixation method and rehabilitation plan are individualized according to the patient's anatomy, health and the condition being treated.
