Trigger points, also known as trigger sites or muscle knots, are described as hyperirritable spots in skeletal muscle that are associated with palpable nodules in taut bands of muscle fibres.

The size of the trigger point nodule varies that according to the size, shape type of muscle in which it is generated. What is consistent that they are tender under pressure, so much so the patient will often wince when pressure is applied this is called the “jump sign”

Compression of a trigger point may elicit local tenderness, referred pain, or local twitch response. The local twitch response is not the same as a muscle spasm. This is because a muscle spasm refers to the entire muscle contracting whereas the local twitch response also refers to the entire muscle but only involves a small twitch, no contraction.

Trigger Point Development

Trigger points manifest sarcomere and motor end plates become over-active. There are many theories of why trigger points occur. With all the theories the same physiological findings can be found:

• Increased acetylcholine (ACh) production (type of neurotransmitter);
• Excess calcium (Ca²) release;
• Hypertension;
• Stress;
• Localised heightened sensitivity;

Trigger Point Classification

Central/Primary Trigger Points; these are the most common type and normally the type that people refer to when talking about trigger points. The central trigger point always resides in the centre of the muscle belly. It should be noted if there will be more if the muscle has more than one belly in a multipennate for example.

Satellite/secondary Trigger; are thought to be a response to central trigger points in neighbouring muscles that lie within the referred pain zone, often when the primary trigger point is inactivated the satellite points will diffuse without intervention.

Attached Trigger Points; are located in area near where the tendon inserts in to the bone and are often exquisitely tender.

Diffuse Trigger Points; occur where multiple satellite trigger points exist secondary to multiple central trigger points, often associated with postural deformities.

Inactive/latent Trigger Points; this applies to lumps and nodules that feel like tri

Active Trigger Points; apply to central and satellite trigger points, a variety of stimulants can activate an inactive trigger point such as forcing muscular activity through pain.gger points but are not painful and are often secondary.  A presence of inactive trigger points may lead to increased muscle stiffness.

Physical Findings

Trigger points are often described and feel like:

• Small nodules the size of a pinhead;
• Pea sized nodules;
• Large lumps
• Several large lumps next to each other;
• Tender spots embedded in taut bands of semi hard muscle that feels like cord;
• Rope like bands;
• The skin over trigger points can often be slightly warmer,

Manual Therapy:Treatment:

There are a number of ways a trigger point can be deactivated in massage the most common technique is applying a medium pressure directly on to the trigger point waiting for pain to ease or twitch response to cease. By applying the pressure too hard or for too long can cause bruising to the patient. There are a number of other ways trigger points can be deactivated mechanical vibration, pulsed ultra sound, electro stimulation low level laser therapy and dry needling. Once the trigger points have been found and treated stretching of that muscle is advised to have a lasting effect of the treatment.

Trigger point therapy is often uncomfortable during the treatment, yet described as a ‘good discomfort’, or ‘good pain’ as patients feel the action on the effective area sis positive as the trapped tissues release. The pain should decrease during a trigger point action, it should not increase, if this occurs, inform your therapist.

There is an option for injections as alternative treatment of local anaesthetics, steroids and botulinum toxin are used when other methods haven’t giving immediate effect and relief but there is concern that long term use or high dosage of anaesthetics can cause muscular necrosis and steroids can weaken tendons, ligaments and bone. We don’t offer this treatment at our Southampton practice, but may use the above manual therapy techniques during a Osteopathy
session or Deep Tissue Massage.

Tim Young M Ost

Southampton Osteopath

YOU Massage Therapy

02380 639747

References:

Davies, C. (2001). Trigger Point Therapy Workbook.Oakland: New harbinger publication Hegben, E., & Rickter, P. (2009). Trigger points and Muscle chain in Osteopathy. Stutgart: Thieme.Niel-Asher, S. (2008).

The Concise Book of Trigger Points .Berkeley: Lotus Publishing, Travel, & Simons. (1999). Myofascial pain and Dysfunction, the trigger point manual upper half of the body, (Vol. 1). Williams & Wilkins.