Approach Considerations
Trigger point (TrP) injections sometimes are performed with bupivacaine, etidocaine, lidocaine, saline, or sterile water. [15, 16, 17, 18] Dry needling is occasionally performed, without the injection of any substance. [19, 20]
TrP injection results are better if an LTR can be elicited. Ultrasonographic guidance can be helpful for recognition of LTR in deeper muscles, but is not helpful in finding TrPs. [21]
Botulinum toxin (BOTOX®) shows promise as a substance that can provide long-lasting relief. [22, 23, 24, 25, 26] Its mechanism of action may be related to the blocking of acetylcholine release at the neuromuscular junction of the dysfunctional motor endplates.
A retrospective study by Avendaño-Coy et al indicated that in combination with physical therapy, intramuscular injections with botulinum toxin type A (BoNT-A) are effective against myofascial pain (MP) syndrome. The study, which involved the records of 301 patients with persistent MP syndrome, found that at 6 months, positive results were achieved with this treatment combination in 58.1% of patients, including 82.9% of those with primary MP syndrome and 54.9% of those with secondary MP syndrome. The effectiveness of therapy in the latter group was influenced by the disorders associated with secondary MP syndrome. [27]
A report by Affaitati et al indicated that a topical anesthetic patch can also relieve myofascial pain, without the discomfort that can result from TrP injections. [28] Patients in the study were separated into groups of 20, one of which was treated for 4 days with a lidocaine patch applied to each patient's trigger point (with patients receiving a total daily dose of 350 mg). The second group received a placebo patch, and the third group was treated with injections of 0.5% bupivacaine hydrochloride.
In members of the lidocaine patch and bupivacaine injection groups, the investigators found significant decreases and increases in, respectively, subjective symptoms and pain thresholds. Although the effects at muscle TrPs and target areas were more pronounced in the injected patients, the lidocaine patients experienced less therapy-related discomfort. Subjective symptoms and pain thresholds did not improve in the placebo group.
Rehabilitation Program
Physical Therapy
Physical therapy for patients with myofascial pain focuses on correction of muscle shortening by targeted stretching, strengthening of affected muscles, and correction of aggravating postural and biomechanical factors. Modalities can be useful in decreasing pain, allowing the patient to participate in an active exercise program. [29]
Corrections of leg-length discrepancies with a heel lift or the use of dynamic insoles also may be helpful. Various other techniques and procedures, including the following, have been demonstrated to be effective in some patients:
A literature review by Ahmed et al suggested that electroacupuncture is more effective than transcutaneous electrical nerve stimulation (TENS) at reducing MP. The study also indicated that treatment duration may affect the success of electrical stimulation in MP but that the frequency and number of treatments may not. [39]
A study by Chan et al indicated that a program of self-massage and home exercise aids in the treatment of MP dysfunction syndrome (MPDS). The study included 31 control patients, who received six sessions of heat therapy and TENS, and 32 patients who received the same treatment, as well as undergoing a program of self-massage and home exercise. The latter group showed greater improvement than the other patients, including significant increases in the pressure pain threshold of trigger points (TrPs) and significant improvements in the neck disability index and the patient-specific functional scales. [40]
A retrospective study by Halder et al indicated that treatment combining onabotulinumtoxinA (BOTOX®) injections with myofascial release physical therapy under anesthesia is effective against myofascial pelvic pain in women. Average pelvic pain scores in the study decreased from 6.4 to 3.7, while the number of trigger points were reduced. Moreover, patient self-reported pelvic pain was characterized as improved by 58% of patients. Patients with chronic bowel disorders were most likely to report no pain improvement, while patients who had undergone past treatment with an incontinence sling were most likely to report pain reduction. [41]
Occupational Therapy
Occupational therapy can be helpful in assessing and setting up ergonomically correct workstations for patients with myofascial pain. Properly set up work sites can help to decrease aggravating postural factors.
Medical Issues/Complications
Trigger points (TrPs) can result from noxious stimuli, such as a herniated disc. Inquire about such precipitating factors in the patient's environment.
The treatment of TrPs can provide temporary relief of visceral pain referred from other organs and can mask the pain of serious conditions (eg, appendicitis, myocardial infarction).
Complications of TrP injections are rare and depend on the area being injected. They include local pain, bleeding, bruising, intramuscular hematoma formation, infection, and, more rarely, neural or vascular injury, or penetration of an underlying organ (which could lead to pneumothorax).
Consultations
Consultation with a specialist in physical medicine and rehabilitation may be indicated and should be arranged as needed.
Other Treatment
See the list below:
-
Osteopathic manipulation techniques may include integrated neuromusculoskeletal release, myofascial release, strain-counterstrain, muscle energy, and high-velocity/low-amplitude manipulation.
