--
"Needling" in order to break up mechanically
the painful and tender tissue is combined with infiltration by
local anesthetic, (trigger point) injections
--
Preinjection blocks (PIB) prevent pain from needle penetration
to sensitive areas. FIIB itself is effective in relieving pain
and relaxing muscle spasm. It relaxes, inactivates instantaneously
the neurogenic component of taut bands and trigger points/tender
spots. PIB also prevents sensitization of tissues and nerve fibers
that occurs after needling. PIB desensitizes hyperalgesic (sensitized)
tissues
--
Somatic block to relieve muscle spasm as well as pain caused
by it
--
Spray inactivates painful tender spots and TrPs. Spray is followed
by movement, which heals and restores function
--
Relaxation exercises relieve muscle tightness, tension. Postural
correction, such as restoration of lumbar and cervical lordosis,
relieves pain
Basic
principle of pain management
The
immediate cause of pain has to be established so treatment can
be specifically focused on the etiologic factors and not limited
to symptomatic relief
CONDITIONS
IN WHICH NEEDLING AND INFILTRATION OF TENDER SPOTS OR TRIGGER
POINT INJECTIONS ARE EFFECTIVE
Injuries
Chronic
trigger points usually in the stage of anatomic pathologic changes
(fibrotic tissue); this applies to myofascial, ligamentous, or
pericapsular TrPs regardless of the cause of damage
Acute
stage of injury immediately after the sprain and/or 1-3 days later.
Trigger point injection stops the pain and relieves muscle spasms
immediately, allowing active movement (limbering exercises). Trigger
point injection accelerates substantially the recovery in both
muscle and ligament sprain
Sport
injuries caused by acute sprain or repetitive stress (i.e., pitcher's
or tennis elbow, golf shoulder, elbow, etc)
Repetitive
stress disorders, such as industrial work causing myofascial or
ligamentous TrPs
Operation
scars and TrPs around the scars, tissues under tension; frequent
after spine operations and hip replacement
Inflammation
Bursitis,
tendinitis, epicondylitis
Arthritis,
including osteoarthritis with TrPs in the pericapsular tissues
and sprained, strained ligaments around the degenerated joints
Fibromyalgia/fibromyositis,
endocrine (thyroid, estrogen) deficiency, vitamin and metabolic
disorders usually develop TrPs from tension or secondarily from
local damage of susceptible tissues
Headaches,
particularly tension headaches. Also migraine headaches have frequently
a tension component inducing TrPs. Injections give considerable
relief in both conditions
Nerve
fiber irritation inducing spasm and consequently TrPs. Radicular
irritation produces a typical rnyotomal distribution of TrPs
TrPs
in emotional stress and tension, anxiety, or depression
Advantages
of trigger point injections
Immediate
relief of pain and spasm caused by pain
Instant
improvement or restoration of function, ambulation, or use of upper extremity Needling is the most effective method for complete
resolution of TrP in chronic stage once fibrotic tissue has formed
TECHNIQUE
OF TRIGGER POINT INJECTIONS, NEEDLING AND INFILTRATION
Trigger
point injection (TI) is a special technique used for the alleviation
of pain caused by the TSs/TrPs.* The ideal goal is to break up
and eliminate the entire underlying abnormal tissue. Three different
commonly used TI techniques are described.
Needling
combined with infiltration is the most effective technique of
TI. Infiltration with a local anesthetic such as 1% lidocaine
or 0.5% procaine is combined with needling (i.e., repetitive insertion
and withdrawal of the needle covering the entire abnormal [painful]
tissue in order to break it up). The tenderness (sensitization)
usually extends over the myotendinal junction and particularly
the enthesopathy at the attach- ment of taut band to the bones
(Fig. 1).
This mechanical
breakup of abnormal tissue (dysfunctional or pathologic) induces
the long-term effect of TI. The technique requires using a sufficiently
long needle to reach the entire area of abnormal tissue, if possible,
from one single skin penetration. In addition the use of a needle
with a larger diameter facilitates the mechanical breakup of the
abnormal tissue. The amount of injected fluid is relatively large
(2-12 mL), because usually an extensive area has to be infiltrated,
ranging from 3 to 25 cm in length and 2 to 10 cm wide. The size
of infiltration depends on the extent of the trigger point and on
the length of the affected muscle fibers.
The
mechanism by which needling and infiltration (N&I) alleviates
pain instantaneously and remains effective for a long period of
time has been discussed", 14 and can be summarized as follows:
N&I breaks up a pocket in which nerve endings are entrapped
along with the inflammatory, irritative substances. In the acute
stage of injury when N&I is highly effective for immediate
relief of pain, and prevents development of symptoms and spasm,
taut formation of taut bands or pathologic scar can be explained
by breaking up a layer of edema that has formed around the damaged
area. In the chronic stage, which occurs probably within 3 or
4 weeks after the injury, a pocket of fibrotic tissue may form,
entrapping the nerve endings along with the irritative, inflammatory
substances .14 This concept is based on general knowledge
of wound healing by formation of scar tissue and mainly on clinical
experience. It was observed that the needle penetration at this
chronic stage is hindered by resistance which is characteristically
fibrotic (i.e., very hard and nonelastic). In TSs/TrPs there seems
to be also a "core" that cannot be relaxed by block
of neurogenic impulses and is of hard "fibrotic" consistency.
This core reacts best to N&I.
Travell's
technique of injecting a small amount of 0.5% procaine into the
TrP to desensitize the most tender spots is another TI method.
With
steroid injection, a short 1.5-inch, thin needle, usually 25 gauge,
is used. Steroids are combined with a small amount (1-3 mL) of
local anesthetic, usually lidocaine. Steroids are not necessary
for myofascial TrP because the technique of needling with breaking
up the abnormal tissue is more effective. In fact, steroids may
induce local myopathy; however, steroids may be useful in the
treatment of passive tissues such as bursitis, tendinitis, epicondyhtis,
or ligament sprain. The disadvantage of steroid injections into
ligaments and ten- dons includes loosening and incomplete healing
of these tissues, which makes them susceptible to reinjury. The
number of steroid injections is limited to 3 to 5 sessions, which
leaves the rest of TrPs untreated.
PREINJECTION
BLOCKS (PlBs)
This
is a new approach that consists of a local anesthetic infiltration
of the nerve which supplies the area where a trigger point injection
(TPI) or other injection will be administered to a sensitive tender
area.
Effects
of PIB:
1.
Prevents pain caused from TPIs by interrupting the transmission
of nociceptive impulses going to the central nervous system (CNS).
2.
Prevents postinjection soreness and pain. Allows for more thorough
needling over larger areas than without PIB.
3.
Makes possible "early mobilization," active limbering
(relaxation) exer- cises, which promote healing and functional
recovery.
4.
Lidocaine silences ectopic neuroma discharges caused by sensitization
of neuroma and corresponding dorsal root ganglion. This desensitization
is not related to the conduction block."'
5.
Applied prior to nerve injury (ligation) FIB prevents pain and
(thermal) hyperalgesia as well as reflex sympathetic vasoconstriction.
Nerve
Blocks
Diagnostic
blocks
Aid
differential diagnosis of the site and cause of pain Help determine
mechanism of chronic pain syndromes
Therapeutic blocks
Control
severe acute postoperative, post-traumatic pain, and pain from
self-limiting diseases
Breaking
of "vicious cycle" involved in some pain syndromes may
provide prolonged relief
Provide
temporary relief to permit other therapies, or used in combination
with other therapies (physical therapy)
Preinjection
block (PIB) administered prior to trigger point injections, paraspinous
somatic blocks, or needling and infiltration of sprained, traumatized,
or inflamed tissue. The PIB prevents pain caused by needle penetration
of sensitive tissue
