Basis, indications and risk

Treatments Basis, indications and risk Patient information Postural hygiene Exercise Maintaining level of Activity Bed rest Pharmacological therapy Neuroreflexotherapy (NRT) Spinal column surgery Surgery for Pain and Pain Clinics Vertebral manipulation Behavioral treatment Epidural injections Facet joint infections Trigger point and ligament infections Rhizotomy Corsets and lumbar belts Traction Physical therapy/physiotherapy Electromyografic Feedback TENS: Transcutaneous electrical Nerve Stimulation Shoe insoles and shoe lifts Acupunture Recommended treatments

Trigger point and ligament injections

They consist of injecting anesthetics or anti-inflammatory drugs -usually cortisone derivatives- into the painful area, either in ligaments or "trigger" points.

Objective

To improve pain and, eventually, inflammation.

Theoretical base

In localized ligaments or muscle fiber lesions, pain nerves are activated. Activation of these nerves causes pain and the release of substances involved in neurogenic inflammation.

Cortisone derivatives have very potent anti-inflammatory effects, but their risks and contraindications disallow continuous administration. In the systematic administration of corticoids only the portion in the bloodstream reaching the swollen area is effective. To increase anti-inflammatory efficacy and decrease risks, a local injection should be administered at the lesion site to obtain a potent local effect and less adverse effects.

This would neutralize the effect of released substances from pain nerves and a decrease in inflammation.

Injection of local anesthetics directly onto the lesion site produces a stronger effect from the administered dose. Its objective is to inhibit pain nerves.

However, although back pain etiology may be due to a local lesion, the affected area is usually greater than the area covered by a local injection. Additionally, although local acute back pain has been traditionally attributed to a faulty posture or strain, to a possible ligament lesion or muscle fiber tearing, it has never been proven that these are actually the cause of pain. In these instances it is difficult to discriminate if pain is due to an injury or to a muscle contraction. Lastly, if pain persists during prolonged periods of time, neural mechanisms are activated to perpetuate pain independently of its initial cause or even if the cause itself has disappeared.

Evidence of efficacy

The studies considered by some of the existing recommendations based on scientific evidence do not prove the efficacy of local injections. The reviewed studies by others show equivocal results in treatment of chronic cases and very few of these studies include acute patients.

A recent systematic review found that phenol injections of the lumbar interspinal ligament and combined steroid and local anaesthesic injections of trigger points may be effective for chronic low back pain patients.

Risks and contraindications

Trigger point or ligament injections may cause temporary pain during a few days at the site of injection.

Indications

The existing recommendations based on scientific evidence do not advise local injections in the treatment of back pain.