Increase in Lactate Without Change in Nutritive Blood Flow or Glucose at Active Trigger Points Following Massage: A Randomized Clinical Trial.

OBJECTIVE: To investigate changes in nutritive blood flow as well as interstitial glucose and lactate within an active myofascial trigger point (MTrP) following massage. DESIGN: Randomized, placebo-controlled trial. SETTING: Subjects were recruited from the general population; procedures were conducted at a research center affiliated with a university hospital. PARTICIPANTS: Adults (N=25) (18-49y old) with episodic or chronic tension-type headache and an active MTrP in the upper trapezius muscle. INTERVENTIONS: Subjects were randomized to receive a single trigger point (TrP) release massage or sham ultrasound (US) treatment at an active MTrP in the upper trapezius muscle. Microdialysis was used to continuously sample interstitial fluid from the MTrP before, during, and for 60 minutes following intervention. MAIN OUTCOME MEASURES: The primary outcome measure was nutritive blood flow within the MTrP as measured by microdialysis ethanol clearance; secondary measures included dialysate glucose, dialysate lactate, and subject discomfort with the procedures. Pressure-pain threshold (PPT) was determined to assess treatment effectiveness. RESULTS: There was no treatment effect of TrP release massage on nutritive blood flow (P=.663) or dialysate glucose (P=.766). The interaction for lactate was significant indicating that dialysate lactate increased for TrP release massage vs sham US (P=.04); maximum lactate increase over baseline was observed at 60 minutes after TrP release massage (P=.007, 0.128 µM, 95% confidence interval 0.045-0.212). Pain evoked by probe placement into an active MTrP was low. An interaction effect on PPT was significant (P=.005). CONCLUSION: TrP release massage of an active MTrP affected anaerobic metabolism as represented by an increase in dialysate lactate without change in nutritive blood flow or dialysate glucose. The lack of a treatment effect on blood flow is discussed.

Changes in blood flow and cellular metabolism at a myofascial trigger point with trigger point release (ischemic compression): a proof-of-principle pilot study.

OBJECTIVE: To demonstrate proof-of-principle measurement for physiologic change within an active myofascial trigger point (MTrP) undergoing trigger point release (ischemic compression). DESIGN: Interstitial fluid was sampled continuously at a trigger point before and after intervention. SETTING: A biomedical research clinic at a university hospital. PARTICIPANTS: Subjects (N=2) from a pain clinic who had chronic headache pain. INTERVENTIONS: A single microdialysis catheter was inserted into an active MTrP of the upper trapezius to allow for continuous sampling of interstitial fluid before and after application of trigger point therapy by a massage therapist. MAIN OUTCOME MEASURES: Procedural success, pain tolerance, feasibility of intervention during sample collection, and determination of physiologically relevant values for local blood flow as well as glucose and lactate concentrations. RESULTS: Both patients tolerated the microdialysis probe insertion into the MTrP and treatment intervention without complication. Glucose and lactate concentrations were measured in the physiologic range. After intervention, a sustained increase in lactate was noted for both subjects. CONCLUSIONS: Identifying physiologic constituents of MTrPs after intervention is an important step toward understanding pathophysiology and resolution of myofascial pain. The present study forwards that aim by showing that proof-of-concept for collection of interstitial fluid from an MTrP before and after intervention can be accomplished using microdialysis, thus providing methodological insight toward treatment mechanism and pain resolution. Of the biomarkers measured in this study, lactate may be the most relevant for detection and treatment of abnormalities in the MTrP.

Responsiveness of Myofascial Trigger Points to Single and Multiple Trigger Point Release Massages: A Randomized, Placebo Controlled Trial.

OBJECTIVE: This study aimed to assess the effects of single and multiple massage treatments on pressure-pain threshold (PPT) at myofascial trigger points (MTrPs) in people with myofascial pain syndrome expressed as tension-type headache. DESIGN: Individuals (n = 62) with episodic or chronic tension-type headache were randomized to receive 12 twice-weekly 45-min massage or sham ultrasound sessions or wait-list control. Massage focused on trigger point release (ischemic compression) of MTrPs in the bilateral upper trapezius and suboccipital muscles. PPT was measured at MTrPs with a pressure algometer pre and post the first and final (12th) treatments. RESULTS: PPT increased across the study timeframe in all four muscle sites tested for massage, but not sham ultrasound or wait-list groups (P < 0.0001 for suboccipital; P < 0.004 for upper trapezius). Post hoc analysis within the massage group showed (1) an initial, immediate increase in PPT (all P values < 0.05), (2) a cumulative and sustained increase in PPT over baseline (all P values < 0.05), and (3) an additional immediate increase in PPT at the final (12th) massage treatment (all P values < 0.05, except upper trapezius left, P = 0.17). CONCLUSIONS: Single and multiple massage applications increase PPT at MTrPs. The pain threshold of MTrPs have a great capacity to increase; even after multiple massage treatments additional gain in PPT was observed. TO CLAIM CME CREDITS: Complete the self-assessment activity and evaluation online at http://www.physiatry.org/JournalCME CME OBJECTIVES: Upon completion of this article, the reader should be able to: (1) Understand the contribution of myofascial trigger points to myofascial pain; (2) Describe an effective treatment for decreasing tenderness of a myofascial trigger point; and (3) Discuss the relative values of single vs. multiple massage sessions on increasing pressure-pain thresholds at myofascial trigger points. LEVEL: Advanced ACCREDITATION: The Association of Academic Physiatrists is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.The Association of Academic Physiatrists designates this Journal-based CME activity for a maximum of 0.5 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.

Myofascial trigger point-focused head and neck massage for recurrent tension-type headache: a randomized, placebo-controlled clinical trial.

OBJECTIVE: Myofascial trigger points (MTrPs) are focal disruptions in the skeletal muscle that can refer pain to the head and reproduce the pain patterns of tension-type HA (TTH). The present study applied massage focused on MTrPs of patients with TTH in a placebo-controlled, clinical trial to assess efficacy on reducing headache (HA) pain. METHODS: Fifty-six patients with TTH were randomized to receive 12 massage or placebo (detuned ultrasound) sessions over 6 weeks, or to wait-list. Trigger point release massage focused on MTrPs in cervical musculature. HA pain (frequency, intensity, and duration) was recorded in a daily HA diary. Additional outcome measures included self-report of perceived clinical change in HA pain and pressure-pain threshold at MTrPs in the upper trapezius and suboccipital muscles. RESULTS: From diary recordings, group differences across time were detected in HA frequency (P=0.026), but not for intensity or duration. Post hoc analysis indicated that HA frequency decreased from baseline for both massage (P<0.0003) and placebo (P=0.013), but no difference was detected between massage and placebo. Patient report of perceived clinical change was greater reduction in HA pain for massage than placebo or wait-list groups (P=0.002). Pressure-pain threshold improved in all muscles tested for massage only (all P's<0.002). DISCUSSION: Two findings from this study are apparent: (1) MTrPs are important components in the treatment of TTH, and (2) TTH, like other chronic conditions, is responsive to placebo. Clinical trials on HA that do not include a placebo group are at risk for overestimating the specific contribution from the active intervention.