The Tender Point Test for healthcare professionals

The Tender Point test is the only test for Fibromyalgia Syndrome (as opposed to for excluding differential diagnoses) that is routinely carried out in the clinical setting. However little or no training in performing the test is often given and variations in carrying it out impact heavily on its effectiveness as a diagnostic tool.

It should be noted that the choice of 11 out of the standard 18 tender points as a diagnostic for Fibromyalgia Syndrome was originally devised as an inclusion test for research and that 11 is an arbitary number. Examiners should also take into account that tender point test scores are typically lower in men than in women. [1]

According to the 1990 ACR Criteria for the Classification of Fibromyalgia, "digital palpation should be performed [on the standard tender point sites] with an approximate force of 4 kg. For a tender point to be considered "positive" the subject must state that the palpation was painful. "Tender is not to be considered "painful." [2]

The thumb pad of the examiner's dominant hand can be used to apply pressure to the evaluation sites during the tender-point examination. This allows the examiner to detect important tactile cues, such as the existence of myofascial trigger points around a tender point site which can lead to a false positive.

There are some common sense guidelines, based on the requirements of the ACR Criteria, for conducting a tender point examination, including:

1. Taking into account that the patient's position during examination, the amount of force applied at the evaluation site, the number of times the evaluation site is palpated, and the method of applying force (instrument vs finger pad) may influence tender-point sensitivity.
2. Ensuring that they (the examiner) know how to recognise myofascial trigger points so as to differentiate between these and tender points. The most obvious signs are that a myofascial trigger point, unlike a tender point, will likely feel like a knot in the muscle and should refer pain or other symptoms elsewhere.
3. Telling the patient before beginning the examination that they need to respond to each tender point examination. The patient should respond with a “yes” or “no” if they have any pain at the site being examined. If the patient's response is “yes,” the examiner should ideally get them to rate the pain on a scale of 0 (no pain) to 10 (worst pain), and record each response.
4. Only palpating each tender point once. It will be easier for the examiner if the patient is in a standard, easy access hospital gown and is in a comfortable position, either sitting or lying down. The examiner should locate the tender point position visually before applying any pressure and should then apply a force equivalent to 4kg, which should be sufficient to blanch the nail bed of the thumb used. The tender point should be palpated for long enough for the patient to respond: some doctors recommend a constant palpation for 4 seconds.
5. There are control sites that can be palpated and recorded to provide baseline documentation of the patient's pain perception. These sites should be less painful and include the nail of the thumbs and the forehead.

The 1990 ACR criteria for the location of tender points are as follows:

1. Occiput: Bilateral, at the suboccipital muscle insertions.
2. Low cervical: bilateral, at the anterior aspects of the intertransverse spaces at C5-C7.
3. Trapezius: bilateral, at the midpoint of the upper border.
4. Supraspinatus: bilateral, at origins, above the scapula spine near the medial border.
5. Second rib: bilateral, at the second costochondral junctions, just lateral to the junctions on upper surfaces.
6. Lateral epicondyle: bilateral, 2 cm distal to the epicondyles.
7. Gluteal: bilateral, in upper outer quadrants of buttocks in anterior fold of muscle.
8. Greater trochanter: bilateral, posterior to the trochanteric prominence.
9. Knee: bilateral, at the medial fat pad proximal to the joint line.

References:

1. Clauw, DJ. Fibromyalgia: Update on Mechanisms and Management. Journal of Clinical Rheumatology: Volume 13(2)April 2007pp 102-109.
2. Wolfe F, Smythe HA, Yunus MB, Bennett RM, Bombardier C, Goldenberg DL, et al. The American College of Rheumatology 1990 criteria for the classification of fibromyalgia: report of the multicenter criteria committee. Arthritis Rheum 1990;33:160---72.