Hip replacement: when to have surgery and what recovery is like

The hip is the joint that carries your body weight with every step, and when the cartilage lining it wears away, walking, climbing stairs or simply putting your socks on becomes a struggle. The good news is that most people with hip pain do not need surgery, and when surgery is the right option, a hip replacement is one of the most successful operations in the whole of medicine.

In this article we explain what lies behind hip pain, what can be done before considering an operation, when a replacement makes sense and what recovery is really like.

What causes hip pain

The most common cause of hip pain in adults is osteoarthritis: the gradual wear of the cartilage that lets the head of the femur turn smoothly inside the pelvis. It usually appears from the age of 50 or 60, although it can come on earlier when the hip has a shape that predisposes it (dysplasia, femoroacetabular impingement) or after a fracture or a previous illness.

Other causes we see in clinic:

• Avascular necrosis of the femoral head: the bone loses its blood supply and collapses. It is more common in younger people and is sometimes linked to long courses of corticosteroids.
• Inflammatory arthritis, such as rheumatoid arthritis.
• Hip fractures in older people with osteoporosis, which almost always need urgent surgery.
• Tendinopathy and bursitis on the outer side of the hip, which hurt when you lie on that side and have nothing to do with the joint itself.

Hip osteoarthritis pain has one particular feature: it is often felt in the groin or at the front of the thigh, rather than on the outer side. It also commonly spreads towards the knee, which leads some people to see a doctor about their knee when the problem lies higher up. That is why the examination at the first appointment matters as much as the X-ray.

How it is diagnosed

In clinic, the doctor examines how the hip moves, checks which movements bring on the pain and looks at how the person walks. A plain X-ray is almost always enough to confirm osteoarthritis and see how advanced it is. An MRI scan is kept for specific cases: suspected necrosis, labral tears in younger people, or when the X-ray does not explain the pain.

One point worth knowing: the degree of wear on the X-ray does not always match how much it hurts. Some very worn hips cause little trouble, while hips with moderate changes can greatly limit daily life. Treatment decisions are based on how the person is doing, not just on the image.

Non-surgical treatment: almost always the first step

Except for fractures and very advanced osteoarthritis with severe limitation, treatment starts without surgery. And for many people, that will be all the treatment they need for years.

Exercise and weight control

This is the measure with the strongest evidence behind it. Strengthening the buttock and thigh muscles takes load off the joint and improves stability when walking. Activities such as an exercise bike, swimming or water-based exercise let you keep moving without punishing the hip. Every kilo you lose reduces the load the joint bears with each step.

Medication

Painkillers and anti-inflammatories help to control the most painful phases, always as prescribed and for the shortest time possible, especially in older people or those with stomach, kidney or heart problems.

Joint-preserving surgery in younger people

When hip pain appears in a young person because of a problem with the shape of the hip (femoroacetabular impingement, a labral tear), hip arthroscopy can correct it before the cartilage is damaged. It is not a treatment for established osteoarthritis, but a way of trying to prevent it.

When to consider a hip replacement

Whether a hip replacement is needed is not decided by the X-ray or by age, but by a combination of three things:

• Your pain is limiting daily life: walking short distances, sleeping, getting dressed, working.
• Your non-surgical treatment is no longer enough, having been followed properly for a reasonable length of time.
• An X-ray confirms wear that justifies the operation.

Operating too early means undergoing surgery that perhaps was not needed yet. Operating too late, when the muscles are very weak and a lot of movement has been lost, makes recovery slower. The right moment is decided between the orthopaedic surgeon and the patient, with clear information about what to expect.

What a hip replacement involves

A total hip replacement replaces both surfaces of the joint: the head of the femur is replaced by a ball on a stem fixed inside the bone, and the socket in the pelvis (the acetabulum) by a cup with a liner in which the new ball turns. Today's materials (metal, ceramic and high-strength polyethylene) are designed to last for decades.

The operation takes between one and two hours and is usually done under a spinal anaesthetic (numb from the waist down), with sedation. There are several surgical approaches (posterior, lateral, anterior), each with its own advantages and precautions; the surgeon chooses the one that best suits each case and their own experience.

When an older person breaks their hip with a fracture of the femoral neck, a partial replacement is sometimes fitted instead, replacing only the femoral head. This is a different, urgent operation, with its own care pathway.

What hip replacement recovery is like

It is the question that worries people most, and the answer is usually a pleasant surprise.

• On the same day or the day after the operation, you start walking with a walking frame or crutches, helped by the physiotherapist.
• You gradually stop using your crutches over about four to six weeks, depending on your strength and balance.
• Full functional recovery takes between three and six months, although relief from the arthritis pain comes much sooner.

For the first few weeks you need to follow some precautions to stop the new hip from dislocating (the ball coming out of its socket). They depend on the approach used, and the team explains them before you go home: in general, avoid bending the hip a long way, crossing your legs or twisting your body with your foot planted.

Once you have recovered well from a hip replacement, you can walk as far as you like, swim, cycle, play golf or dance. Repetitive high-impact sports (long-distance running, jumping) are not advised because they speed up wear of the implant.

Risks, and how long a hip replacement lasts

Like any major surgery, a hip replacement carries risks, which are uncommon but worth knowing about: infection of the implant, dislocation, venous thrombosis (prevented with medication and getting moving early), a small difference in leg length and, in the long term, loosening or wear of the implant. Individual risk depends on age, weight, other conditions and the state of the muscles, and it is assessed before any decision is made.

Joint registries in several countries show that the vast majority of hip replacements are still working after fifteen or twenty years. If a replacement loosens or wears over time, it can be replaced, although that second operation is more complex than the first.

If your hip hurts

Hip pain that lasts more than a few weeks, wakes you at night or is already affecting what you do deserves an assessment. In the Orthopaedics unit at Rincón Salud we assess each case with an examination and imaging on site, and plan treatment step by step: non-surgical options first, and surgery only when it is the best option for that person. You can book an appointment with our team.