Piriformis syndrome: symptoms, treatment and how long it lasts

The sciatic nerve runs from the lower back through the buttock and down the back of the leg. Several muscles lie close to it in the buttock. The piriformis is one of them, a muscle that sits deep in the buttock area and attaches between the tailbone and the thighbone. When it becomes tight or irritated it is thought to press on or irritate the nerve, producing pain in the buttock and sometimes further down the leg.

The diagnosis is mostly made from the story and a clinical examination. The Dudley Group leaflet, which is written for people being offered an injection, says the muscle can become inflamed, tight or go into spasm. A related, broader term you may hear is deep gluteal syndrome, which RNOH uses to cover all causes of irritation of the sciatic nerve as it passes through the muscles and soft tissues of the buttock.

RNOH says education about the positions and activities that irritate the nerve, activity modification and exercise are first-line. Practical examples it gives include reducing sitting time, using a cushion on hard surfaces and avoiding a wallet or other items in the back pocket when sitting.

Exercise is described as helping by improving movement and blood flow to the nerve, improving the health of the buttock muscles and tendons and improving pelvic control in standing and walking. A physiotherapist can tailor the exercises, and RNOH says manual therapy only temporarily reduces muscle tension, so it needs to be combined with exercise for long-term change.

If self-management is not enough, other options exist. These are summarised in the table below.

RNOH describes deep buttock pain that may extend into the back of the thigh and, in some people, further into the lower leg and foot, sometimes with tingling or numbness that can feel similar to sciatica. Pain is often triggered by activities that strongly use the deep buttock muscles, such as walking, running uphill or climbing stairs. In more severe cases a person may start walking with a limp.

The NHS lists the usual features of sciatica as a sharp or burning pain down the back of the leg, tingling like pins and needles, numbness and weakness, which may be worse when moving, sneezing or coughing. It also points out that you probably do not have sciatica if you only have back pain. In practice, a GP or physiotherapist will think about whether the nerve is being irritated in the spine, as with a slipped disc, or in the buttock.

None of the UK pages read for this guide give a fixed recovery time for piriformis syndrome itself. The nearest guide is the NHS page on sciatica, which says it usually gets better in a few weeks to a few months, can sometimes last longer and can return if you have had it before.

The NHS suggests carrying on with normal activities as much as possible, starting gentle exercise as soon as you can and not sitting or lying down for long periods. It says that even if moving hurts, it is not harmful and can help you get better faster.

If you have an injection, the Dudley Group leaflet says the steroid usually takes 24 to 72 hours to take effect and up to one week to reach its maximum benefit. It also says the injection may take up to six weeks to relieve pain, that pain can be worse for a few days (and in some cases up to two weeks) and that for some people it does not help at all.

RNOH says muscles and soft tissues in the buttock may press more on the nerve, which can restrict its movement or affect its blood flow. This sometimes develops after trauma, such as a fall onto the buttock, or because of inflammation related to muscle or tendon injury or overuse. Habitual postures and movement patterns, for example the way someone walks, runs or stands, that reduce the space the nerve has to travel through may also contribute.

The NHS lists the more common causes of sciatica as arising from the spine: a slipped disc, which it says is the most common cause and becomes more likely with age, spinal stenosis, spondylolisthesis and back injury. Distinguishing these from a buttock cause is one reason a proper assessment is worthwhile rather than assuming the diagnosis from an internet description.

Buttock and leg pain has more than one possible source, and the treatment depends on which it is. The table sets out what the NHS and RNOH say about each. A GP or physiotherapist is the right person to tell them apart.

According to RNOH, in most cases a doctor or physiotherapist will diagnose from the symptoms and a number of tests when examining the hip. Imaging such as MRI may be used to gain more information but is not always necessary. In many parts of the UK the NHS says you may be able to refer yourself to community musculoskeletal (MSK) services for physiotherapy without needing a GP referral.

The Dudley Group leaflet says the muscle can be injected with local anaesthetic, with or without steroid. The anaesthetic helps the muscle fibres relax and the steroid can relieve inflammation. The leaflet states plainly that the injection is not a cure for the cause of the pain and is used to reduce its level and to help show whether the piriformis is involved.

It describes the procedure as a day case, done while you are awake and lying on your stomach, with X-ray or ultrasound used to guide the needle. The procedure itself takes 15 to 20 minutes, and the leaflet asks you not to drive afterwards.

The leaflet lists bruising, temporary leg numbness or weakness lasting three to four hours, a very slight chance of infection and a few days of worse pain as the common effects, and says serious complications are rare. People with diabetes may see a slight rise in blood sugar for up to two weeks. It adds that if you do not strengthen your muscles, the benefit will be very short-lived, because the injection only relieves pain.

Most buttock and sciatic-type pain is not an emergency. The NHS says to see a GP if sciatica has not improved after a few weeks of home treatment, is getting worse or is stopping you doing your normal activities. It advises going to A&E or calling 999 if you have sciatica on both sides, weakness or numbness in both legs that is severe or getting worse, numbness around or under the genitals or around the bottom, difficulty starting to pee or not being able to pee or control it, or not noticing when you need to poo or being unable to control it when this is not normal for you. These can be symptoms of a serious back problem that needs hospital treatment as soon as possible.

The NHS says that in many areas you can get help such as physiotherapy from community musculoskeletal (MSK) services without needing a referral from a GP. Otherwise your GP can assess you, suggest self-care and refer you on if needed.

Physiotherapy is free of charge on the NHS throughout the UK, but the NHS notes that waiting times can be long and that you can also get it privately. Injections of the type described above are given by pain management or musculoskeletal specialists, usually after a consultation where alternatives are discussed.

Surgery is not a routine step. RNOH says it is discussed only if symptoms do not improve with non-operative management.

The NHS says sciatica usually gets better in a few weeks to a few months but can last longer and may return. The same pattern of improvement and flare-ups is reasonable to expect from buttock-based nerve irritation, although the sources describe it less precisely. RNOH suggests pacing activities by breaking them into smaller chunks with rest breaks, and notes that walking aids may reduce compression on the nerve and allow you to walk more with less pain in the short term.

To lower the chance of recurrence, the NHS suggests staying active, using a safe lifting technique, keeping good posture when sitting and standing and, if relevant, losing weight and not smoking. Physiotherapy is free on the NHS throughout the UK, though the NHS notes waiting times can be long and that you can also get it privately.