Sciatica vs Hamstring Tightness: How to Tell the Difference

Sciatica is often a word used to describe changes in sensation of the back of the leg and calf. However, the medical definition of sciatica is actually quite specific and relates to pain and sensations that are driven by irritation or sensitivity of the nerve roots that leave the spine and form the sciatic nerve. 

 

Pain that is generated by irritation to nerve roots is referred to medically as radicular pain and is often associated with peculiar sensations of burning, electric shock type feelings, crawling, trickling water or other unusual sensations, which are generated via sensory nerve fibres within the nerve root. 

 

In more severe cases of nerve root irritation the motor nerve fibres (the fibres that send messages to our muscles) can be involved, leading to muscle weakness. In the case of the sciatic nerve roots this can cause weakness in the buttock, hamstring, calf and foot muscles. Irritation of motor fibres can also cause muscle tightness due to hypersensitivity. 

Discomfort or sensation of tightness in the back of the thigh can also be generated by somatic pain which is a term used for pain which is perceived by the brain to be in one place but is actually being generated somewhere else that shares the same nerve supply as where we perceive the pain to be. This can be from any soft tissue structure eg joint, ligament, muscle, nerve sheath. 

 

Both radicular pain and somatic pain are often described as referred pain. Unlike muscular pain which is usually experienced during activity or when muscle tissue is on stretch, referred pain can often occur at rest or during prolonged activities like sitting. This is why back of thigh pain is not always caused by a tight hamstring muscle. 

So how do you know if the tightness in the back of your thigh is due to the hamstring muscle or the sciatica nerve ? Determining whether your symptoms are caused by a tight hamstring or sciatica is important because the treatment can be very different. 

 

A diagnosis of muscular hamstring tightness can usually be concluded if tightness is the only symptom experienced and all other potential drivers that could be causing tightness have been assessed and somatic or radicular referred pain excluded. 

 

Static stretching can be helpful in relieving hamstring tightness; however, there is more evidence that active stretching where you are using other muscle groups to lengthen hamstring musculature is better at improving flexibility of the hamstring muscle. 

 

It is not unusual for someone to have both hamstring muscle tightness and somatic referred pain occurring in conjunction with each other. In these cases active stretching may still be beneficial; however, the cause of somatic pain also has to be identified and treated. 

If you are experiencing hamstring muscle tightness and have associated radicular symptoms as previously mentioned eg burning, electric shock-like feelings, muscle weakness etc then this is more likely to be true medically defined sciatica. 

 

Many people ask, should you stretch sciatica? In these cases stretching is not always beneficial and can aggravate symptoms due to increased tension across sciatic nerve roots and structures that may be irritating them. 

 

The answer to should you stretch sciatica depends on what is causing your symptoms. If your back of thigh pain is being driven by nerve root irritation rather than a muscular problem, stretching alone is unlikely to resolve the issue and may even make symptoms worse. 

Careful assessment and testing by a physiotherapist can help provide you with the information you need to diagnose the cause of hamstring tightness and any other associated symptoms you may have. This allows rehabilitation to be directed towards the causes of your symptoms rather than simply treating the feeling of tightness. 

 

Whether your symptoms are due to a tight hamstring or sciatica, an accurate diagnosis is the first step towards resolving your back of thigh pain and returning to normal activity.