Diagnostic ultrasound ( PDFDrive )

CHAPTER 25 Musculoskeletal Interventions 909
c
A
f
N
B
C
FIG. 25.21 Ultrasound-Guided Aspiration and Injection of Multiloculated Ganglion Cyst. (A) Baseline sonogram shows a multiloculated
cyst (c) within the vastus lateralis muscle of the left knee and supericial to the lateral margin of the femur (f) in a 41-year-old woman. (B) A
20-gauge spinal needle (N) was initially positioned into the proximal component of the cyst. (C) Subsequently the needle was redirected into the
distal component. Multiple lavages and aspiration enabled complete decompression of the cyst (not shown).
tibioibular joint. 33,34 Ultrasound guidance allows the clinician
to avoid intratendinous injections as well as adjacent neurovascular
structures. Furthermore, the needle may be redirected as necessary
in the presence of a multiloculated cyst (Fig. 25.21). We ind
that performing a lavage technique similar to that employed in
treating calciic tendinosis results in progressive dilution of the
cyst contents, thereby permitting complete aspiration. In the
upper extremity, where cosmesis may also be an issue, use of a
rapidly absorbed corticosteroid may reduce potential complications,
such as depigmentation and local atrophy. Similar considerations
apply when aspirating and injecting parameniscal
and paralabral cysts. hese cysts occur at sites of torn and/or
degenerated ibrocartilage and are most oten present in the knee,
hip, and shoulder. hese cysts are similar to ganglion cysts in
consistency but oten contain additional echogenic debris. In
the shoulder, paralabral cysts have been associated with development
of a compressive neuropathy, because they can occur in
close proximity to the suprascapular nerve. 35 he approach used
in aspirating these cysts is variable, depending on location and
orientation, as well as location of adjacent neurovascular structures
(Figs. 25.22 and 25.23, Video 25.3).
Calciic Tendinitis
he presence of symptomatic intratendinous calciication involves
the deposition of calcium hydroxyapatite. his oten appears
as a nodular echogenic mass within the tendon, which may or
may not display posterior acoustic shadowing. 36 Although most
oten afecting the shoulder, this may occur elsewhere in the
musculoskeletal system. Ultrasound-guided fragmentation and
lavage, also known as barbotage, has been described as an
excellent method to fenestrate the calciication and reduce the
level of calciication and to deposit therapeutic agents. 37-40 Singleand
dual-needle techniques have been described and appear to
be comparably efective. I currently use a single-needle technique,
with the needle acting as inlow for anesthetic and sterile saline
and as an outlow for the calcium solution (Fig. 25.24). he
elasticity of the pseudocapsule encasing the calciication is suficient
to decompress the calciic mass in the majority of cases
(Video 25.4). Ater multiple lavages, the needle is used to inject
the anesthetic and antiinlammatory mixture. he injected mixture
is distributed within the adjacent subdeltoid bursa in most cases.
If the calciication is too small or fragmented, precluding lavage
and decompression, the single needle is used to fenestrate the
calcium deposit, and a peritendinous therapeutic injection has
been shown to be efective.
INTRATENDINOUS INJECTIONS:
PERCUTANEOUS TENOTOMY
Image guidance can be useful for performing percutaneous
tenotomy and intratendinous injections with either autologous
blood or platelet-rich plasma (PRP). 41-45 hese methods are
associated with secondary release of local growth factors, such
as platelet-derived growth factor, which in turn may produce a
direct healing response. 44 Preliminary data show signiicant
promise in promoting ultrasound-guided tendon repair. “Dry
needling” techniques have been employed successfully in patients
with lateral epicondylitis refractory to other conservative