What are spine injections?

Spine injections are medical treatments used to manage acute or chronic pain, inflammation, or other symptoms associated with the spine. They involve delivering medication directly into or around the spine to reduce pain and improve function. These injections are often used when more conservative treatments, such as physical therapy, medications, or rest, haven’t provided sufficient relief. https://www.cheltenhamspineclinic.co.uk/spine-injections/

Spine injections should only be performed by a back or spine expert, preferably spinal surgeons who understand the spine best of all. We regularly perform spine injections safely and successfully at the UK Spine Centre. Our lead Consultant Mr Caspar Aylott is a world renowned back doctor and has performed more than 5000 injections and has great experience in making injections work.

Simple Spine Anatomy

The spine extends from the base of the skull down to the coccyx. There are seven cervical vertebra, twelve thoracic vertebra with accompanying ribs and five lumbar vertebra. Below this we have the sacrum which forms part of the pelvic ring connected by the sacroiliac joints. Hanging off the bottom of the sacrum is the coccyx often referred to as the ‘tail bone’. https://www.britannica.com/science/vertebral-column

The vertebrae are connected together by the discs which act as shock absorbers. At each level of the spine at the back are a pair of joints called the facet joints. These joints resemble the small joints in the fingers.

The spinal cord starts at the top of the neck and runs down through the spinal canal usually terminating around the upper lumbar region around L1 vertebra level. Multiple nerve roots come off the bottom of the spinal cord and continue down through the lumbar spinal canal. These nerve roots are referred to as the caudal equine which means ‘horses tail’ and go on to supply everything below the waist such as legs, bladder bowels, sexual function etc. Nerve roots exit through side canals called the neuro-foramen at each level of the spine. These nerves are numbered according to the vertebral level where they exit. So there are five lumbar nerves because there are five lumbar vertebra.

Causes of Spine Pain

Mechanical or axial back or neck pain usually arises from either the discs or facet joints or a combination of both. https://ukspinecentre.co.uk/ageing-and-back-pain/

https://www.nhs.uk/conditions/back-pain

Sacroiliac joint pain is an uncommon cause of back pain making up about 5% of cases but is over diagnosed by non specialist allied health workers in the community. Similarly back pain less commonly arises from the muscles. https://www.cheltenhamspineclinic.co.uk/back-pain/

85% of individuals will suffer with back pain during their life. https://ukspinecentre.co.uk/back-pain/

https://www.mayoclinic.org/diseases-conditions/back-pain/symptoms-causes/syc-20369906

Pressure on nerve roots in the lumbar spine typically causes pain which radiates down the leg often associated with pins and needles or sciatica. This general description of this is ‘sciatica’. Pressure on a nerve in the neck can cause similar painful symptoms shooting down the arm which is called brachialgia. Another term for this type of pain in the arm or leg is radiculopathy.

Types of Spine Injections

There are several different types of spine injections, each designed to target specific areas of the spine or the nerves that may be causing pain. https://ukspinecentre.co.uk/treatments/spine-injections/

The most common types include:

1. Epidural Steroid Injections (ESIs)
   These are one of the most common types of spine injections. The medication is injected into the epidural space, which is the area surrounding the spinal cord and nerve roots. The goal is to reduce inflammation and relieve pain caused by conditions like herniated discs, spinal stenosis, or sciatica.
2. Facet Joint Injections
   Facet joints are small joints located between the vertebrae in the spine. When these joints become inflamed or damaged, they can cause localised pain. Facet joint injections involve injecting a local anaesthetic and/or steroid directly into the affected joint to reduce pain and inflammation. https://spinesurgeons.ac.uk/Booklet-Lumbar-Facet-Joint-Injection
3. Selective Nerve Root Blocks (SNRBs)
   This type of injection targets a specific nerve root that is causing pain. By delivering a local anaesthetic or steroid medication, this injection can help diagnose and treat nerve-related pain caused by conditions such as radiculopathy (nerve compression). https://spinesurgeons.ac.uk/Booklet-Lumbar-Nerve-Root-Block
4. Sacroiliac (SI) Joint Injections
   The sacroiliac joints are located at the base of the spine, where the sacrum and pelvis meet. When these joints become inflamed, they can cause lower back and leg pain. SI joint injections help reduce inflammation and manage pain in this region. https://www.mayoclinic.org/diseases-conditions/sacroiliitis/symptoms-causes/syc-20350747
5. Trigger Point Injections
   Trigger points are areas of muscle that are tight and painful, often referred to as muscle knots. Injections into these points typically contain a local anaesthetic and may be used to relieve muscular pain associated with back conditions.
6. Medial Branch Blocks
   This procedure targets the nerves that supply sensation to the facet joints. It’s often used as both a diagnostic tool and a treatment to help identify the source of spinal pain and to provide short-term pain relief.

How Spine Injections are Performed

The injection is typically performed by a orthopaedic spine surgeon or pain management specialist or neurologist in a controlled setting (operating theatre commonly), often with the patient lying on their stomach or side. The procedure should only be performed by a back expert or spine specialist. Before the procedure, the area is cleaned, and a local anaesthetic may be applied to numb the skin. Occasionally sedation is offered beforehand if the patient is particularly anxious. A needle is then inserted into the target area under imaging guidance (such as fluoroscopy or CT scans) to ensure accuracy. The medication is injected, and the needle is removed. https://www.spine-health.com/video/epidural-steroid-injections-back-pain-and-leg-pain-video

Accurate targeting of the injection is very important so the experience of the specialist is important along with real time high quality imaging during the procedure. 

How painful is a Spine Injection

Spine injections should not be particularly painful when performed by an experienced Back Doctor or Spine Specialist like Mr Aylott who is performing this treatment regularly. A scratch is felt as the small needle goes through the skin and sometimes some temporary discomfort is felt in the leg if the injection is given around the compressed nerve root. The majority of patients manage very well with local anaesthetic. A small number of more anxious patients benefit from sedation and wake up immediately after the procedure is finished.

How quickly does an injection work

Injections may work within a few hours of the procedure or more slowly over a week or sometimes up to one month. Occasionally back or leg pain can flare up for a few days after the procedure before hopefully improving. 

We often encourage exercise and rehabilitation alongside injections and this can normally commence the day following the procedure. https://www.hopkinsmedicine.org/health/conditions-and-diseases/epidural-corticosteroid-injections

Benefits of Spine Injections

Spine injections can offer several benefits, including:

• Pain relief: The primary goal is to reduce inflammation and ‘block’ pain, often providing significant relief.
• Diagnostic value: Some injections can help pinpoint the source of pain, especially in cases where the exact cause is unclear.
• Improved mobility: By reducing pain, patients may experience greater mobility and functionality, allowing them to engage in physical therapy and other rehabilitation measures.
• Avoiding surgery: In many cases, spine injections offer an alternative to more invasive procedures, such as surgery.

Risks and Side Effects

Like any medical procedure, spine injections come with very small risks. https://orthoinfo.aaos.org/en/treatment/spinal-injections/

These may include:

• Infection: Although rare, there is a small risk of infection at the injection site.
• Nerve damage: The needle can accidentally injure a nerve or surrounding tissues.
• Bleeding: Some patients may experience bleeding at the injection site, especially those with clotting disorders or on blood-thinning medications.
• Side effects of steroids: If steroids are used, they can cause side effects such as weight gain, high blood sugar, or mood changes, although these effects are generally short-term.

Who Can Benefit from Spine Injections?

Spine injections are commonly used for individuals who suffer from chronic back or neck pain due to conditions such as:

• Herniated or bulging discs
• Degenerative disc disease
• Spinal stenosis (narrowing of the spinal canal)
• Sciatica (pain radiating down the leg due to nerve compression)
• Facet joint arthritis
• Spinal injuries
• Osteoarthritis
• Rheumatoid arthritis
• Inflammatory spine disease such as ankylosing spondylitis

They are often recommended when other treatments, such as physical therapy, medications, or lifestyle changes, haven’t sufficiently managed the pain.

How Long do Spine Injections Last

This is very difficult to predict. Injections may not work at all or sometimes can lead to complete relief and permanent recovery. The main determinant here is the underlying problem which is being treatment.

For example if an injection is treating sciatica associated with a disc herniation (disc prolapse, slipped disc) then if the disc herniation goes on to shrink which is the natural history for most then one injection may fix the problem.

Another example is sciatica associated with severe spinal stenosis and nerve root compression. This type of stenosis particularly if caused by bony overgrowth of the joints will not just disappear so the underlying problem in the spine remains and symptoms are likely to relapse at some stage.

It is very difficult to predict how long an injection will last if effective because there are many variables to consider. It is an oversimplification to state that injections will wear off after a few months as is sometimes said because it depends on the condition and perhaps also what else the individual is doing to help themselves with appropriate exercise and rehabilitation. These are the type of considerations that an experienced Spine Specialist like Mr Aylott will be considering in discussion with the patient.

How Often Can I Have a Spine Injection

There is NO specific number to this. It is not correct to say as sometimes we hear that someone can only have three injections! The decision to repeat an injection is based on the level of pain and the response to previous similar injections. In principle if an injection works well with a prolonged period of relief then it may be worth while repeating the injection if symptoms return. It is really for the patient to decide whether they feel an injection has been sufficiently helpful to warrant a repeat. However if an injection does not work or only lasted a short time such as a few days or weeks then there is probably little point in repeating an injection because the outcome will likely be similarly disappointing. The threshold for repeating an injection may be lower if other options such as surgery are not appropriate or other forms of conservative treatment have not worked. https://pubmed.ncbi.nlm.nih.gov/26815255/

It is also important to understand that an injection that has worked well on one occasion may not be successful when repeated. Conversely sometimes a repeated injection may work better than the first time. The point is that whether injections work or last is an inexact science. What we can say is that  technically well performed injections have a greater chance of being successful. https://boneandjoint.org.uk/Article/10.1302/0301-620X.100B10.BJJ-2018-0461.R1

Conclusion

Spine injections can be an effective treatment option for managing back and neck pain, particularly when more conservative approaches have failed. https://www.nhs.uk/conditions/steroid-injections/

While having injections carry very small risks, they can provide significant pain relief and improve quality of life for those suffering from chronic spinal conditions. If you’re considering spine injections we would recommend seeing a specialist like Mr Caspar Aylott at the UK Spine Centre who will diagnose your back problem accurately and then discuss best practice treatment options which may include spine injections.