Piriformis Syndrome is a condition that affects the rear area of the pelvis, when the sciatic nerve is compressed by a muscle in the buttock area, called by the same name, i.e. piriformis. It causes, often undiagnosed, pain in the buttock region, which can spread to the sciatic nerve, with consequent sciatic pain and varying degrees of discomfort in the lower limbs.
The current definition of the syndrome identifies five main features, which do not always appear at the same time:
- History of local trauma;
- Localised pain around the sacroiliac joint and the buttocks, extending along the route of the sciatic nerve and associated with difficulties in walking;
- Acute pain spasms when bending down or when standing up;
- Presence of a palpable tapered mass in the area of the piriformis muscle.
- Positive Lasègue (or Lazarević’s sign) test.
Piriformis Syndrome affects women more frequently (at a ratio of approximately 6:1 compared to men), above all in those aged 30 to 40.
Let’s look at the symptoms, causes and above all remedies to alleviate the pain caused by Piriformis Syndrome.
The Piriformis muscle: some anatomical notes
The Piriformis muscle is a small flat muscle with a triangular shape, located behind the hip at a deeper level than the Gluteus Maximus. It originates from the front surface of the sacrum, from the sacrotuberous ligament and the greater sciatic foramen, leading on to connect to the top of the greater trochanter of the femur.
The Piriformis is one of the six lateral rotator muscles of the hip and is essential to perform movements of extrarotation, abduction and extension of the femur; it also helps to stabilise the hip joint.
As the Piriformis muscle is innervated by branches from the sacral plexus (L5-S2), it is influenced by dysfunctions of the lower lumbar region. Its special feature is the fact that it is anatomically in close contact with the sciatic nerve, which passes deep below it to then exit via the subpiriformis foramen. Therefore retractions, contractures, trauma or inflammation of the Piriformis muscle can significantly affect the sciatic nerve.
Causes of Piriformis Syndrome
The causes of Piriformis Syndrome are still not completely clear and it is often difficult to identify the reasons leading to this dysfunction. Below is a list of the most common causes:
- Trauma origin: for example, falling onto the buttocks, often several months before the onset of pain. Trauma in these cases can lead to inflammation and muscle spasms, with subsequent irritation of the sciatic nerve.
- Dysfunction of the sacroiliac joint.
- Dysfunction of the lower lumbar region, in particular of vertebrae L5-S2.
- Herniated disc located in the zone L5-S1, which irritates the sciatic nerve.
- Heterometry of the lower limbs, i.e., a discrepancy in the length, of varying extent, between the right and left leg.
- Consequence of a hip replacement operation.
- Abnormality of the relation between the Piriformis muscle and the sciatic nerve.
- Stiffness of the hip joint.
- Problems related to foot pressure on one or both feet.
Symptoms of Piriformis Syndrome
Piriformis Syndrome causes above all pain in the buttocks, with or without the spread of pain to the rear of the thigh, which at times can extend through to the knee or calf. The pain is often more acute when seated, due to the compression of the muscle and sciatic nerve in this position.
Specialist doctors, thanks to a clinical history and some specific tests, such as the Pace test, Freiberg test and the FAIR test, can diagnose this syndrome. On the contrary, instrumental tests are used only to exclude other existing pathologies.
A differential diagnosis should be made taking into consideration all conditions related to the structures around the piriformis muscle, such as coxalgia (hip pain), problems with the sacroiliac joint, lower back pain related to a herniated lumbar disc, lumbar stenosis or lumbar facet syndrome. In particular, the herniated disc can produce symptoms very similar to those of the piriformis Syndrome, and therefore an MRI scan of the lumbar region is often recommended to exclude this possibility.
How to treat Piriformis Syndrome: stretching and useful exercises
A conservative approach is normally sufficient to remedy this syndrome. In medical terms, non-steroidal anti-inflammatory drugs (NSAIDs) and muscle relaxants have been shown to be effective against local inflammation, pain and muscle spasms.
It is important to see a physiotherapist specialised in musculo-skeletal disorders, because thanks to therapeutic exercises and manual therapy techniques, he/she will help you to correct any biomechanical problems cause by changes in posture or joint dysfunctions, thus working at the root of the problem. Techniques used to reduce Piriformis muscle spasms are also useful, such as deep friction massages or Tecar therapy.
Stretching exercises for the Piriformis muscle can be highly effective in the daily relief and management of symptoms, because they help to stretch and relax the muscle. These are very similar exercises to those for sciatica, simple and safe, which once learned can be repeated alone on a regular basis at home: Lie down on your back and repeatedly flex the hip through at least 90°, abductions and extrarotations
When a treatment based on physiotherapy, stretching, physical and pharmacological therapy is not sufficient, you can discuss with your specialist doctor options of invasive therapies to treat Piriformis Syndrome. Among these, a key role is that played by local injections of anaesthetics and corticosteroids. If conservative treatments fail, the doctor may also consider the option of surgery, which consists in “releasing” the piriformis muscle and neurolysis of the sciatic nerve. Fortunately, cases resorting to surgical intervention are extremely rare.
How long does the Piriformis Syndrome last? Recovery times with physiotherapy
Once the diagnosis of Piriformis Syndrome is confirmed, with the correct treatment symptoms should start to disappear relatively quickly: the pain and acute phase usually passes in around 7-14 days if a period of rest is taken together with physiotherapy.
If the physiotherapist and/or osteopath session shows other dysfunctions such as blocked joints or postural problems that may cause the syndrome to return, it may be recommended to follow a long-term treatment plan to correct these aspects and thus avoid a relapse.