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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_5830_Библиотеки_им_академика_М_И_Перельмана.pdf
BLADDER AND PELVIC FLOOR MUSCLES
LEFT
c
Figure 3.15, cont’d c. Hypotonic left pelvic fl oor.
slack or defi cient fascial gap (Dietz et al 2005). Concurrently, clinical signs consistent with a loss of myofascial support may be present,
including: stress and/or urge urinary incontinence, organ prolapse,
loss of segmental stability of the ipsilateral sacroiliac joint and an
affi nity towards additional compression to the inferior aspect of the
pelvis (Sapsford 2004, Lee 2004). Moreover, if the asymmetry is
due to unilateral hypoactivity of the PFM, attempts at an isolated
contraction may begin to normalize the asymmetry and the clinical
pattern of presentation will be similar to that of a PVD, indicating
a loss of myofascial support (Fig. 3.15c).
Diligent observation and clinical reasoning are essential in establishing the source of the asymmetry in order to determine the
appropriate intervention and provide an indication of prognosis. If
the source of the asymmetry is hypertonicity, treatment will be
contrary to that prescribed for asymmetry resulting from hypoactivity. If a structural defi cit in the endopelvic fascia is detected, this
may suggest a poorer prognosis and the need for possible surgical
consultation. To complicate matters further, it is common from a
clinical perspective to see combinations of hypertonicity and loss
of fascial support. Furthermore, encroachment resulting from a
fi broid, cyst or, asymmetry from altered fascial tension as a consequence of surgery must also be taken into consideration.
It is important to consider that the diagnosis of a PVD, fi broid
or cyst via an imaging study is a challenging, and in the case
of the PVD controversial, undertaking (Nguyen et al 2000, Dietz
et al 2005). Furthermore, such conclusions are beyond the scope of
81
82
3 Image interpretation: qualitative
a
b
Figure 3.16 USI of the bladder (transverse) – resting symmetrical presentation.
a. Normal resting ultrasound image of the bladder. b. Resting image
demonstrating bilat
midline aspect of the inferior border of the bladder.
eral hypertonicity of the PFM. Note the elevation of the
BLADDER AND PELVIC FLOOR MUSCLES
practice of rehabilitation professionals. However, therapists must be
prepared to handle suspicions of such fi ndings in a timely and professional manner. Specifi cally, it is suggested that if a questionable
structure is identifi ed, an image of it should be saved and then
passed on to the referring physician with a note indicating that
during an USI assessment aimed at determining the functional
status of the PFM the structure was detected. Moreover, as the
identifi cation of such structures from an imaging study is beyond
the therapist’s scope of practice, the physician will need to address
the necessity for further investigation. If the structure is identifi ed
by the patient, then they should be informed of the steps that the
therapist is going to take and asked to return to their physician. If,
however, the structure is not identifi ed by the patient it is likely
prudent to forward the information to the physician without alarming the patient.
Tonic activity and positional bladder stability during spinal loading
After considering the symmetry in size and shape of the bladder,
the patient is asked to perform a task that loads the spine and
increases IAP, such as cough, sneeze, ASLR (Mens et al 2001, Lee
2004) or a modifi ed active leg raise (Ferreira et al 2004) (Fig.
3.17a, b). The PFM, along with TrA and the diaphragm, form the
muscular boundaries of the abdominal cavity and work in a coordinated fashion to produce and control IAP (Hemborg et al 1985,
Hodges et al 1997, 2003b). The degree of coordination is refl ected
by the positional stability of the bladder during the loading situation (cough, sneeze, leg lift etc.). This concept is illustrated by the
fi ndings of O’Sullivan et al (2002) who identifi ed a signifi cant
descent of the bladder in individuals with sacroiliac joint pain
during an ASLR, as opposed to a normal comparison group in
which little motion was observed. They hypothesized that in the
painful group, an altered motor control strategy, which employed
a straining-type activation of the diaphragm and superfi cial abdominal muscles, resulted in an increased IAP, which ultimately overcame the ability of the pelvic fl oor (PFM and the associated fascia)
to support the bladder, and resulted in its descent. Conversely, in
the normal group it appeared as though the PFM were capable of
balancing the downward pressure on the bladder, keeping it relatively stable throughout the task. This was likely due to a motor
control strategy involving a coordinated contraction of TrA, diaphragm and PFM, which produced a reasonable increase in IAP,
and pre-activation followed by coordinated tonic activity of the
PFM, which served to directly support the bladder. Similar neuromuscular coordination has also been shown to occur during a
cough (Constantinou & Govan 1982, Barbic et al 2003). Although
83
84
3 Image interpretation: qualitative
a
Figure 3.17 Ultrasound probe position to monitor bladder position during
a. an ASLR.
the pre-activation of the PFM is a matter of milliseconds, hence
undetectable to the naked eye, the impact of the coordinated activity of the muscles surrounding the abdominal cavity as well as the
tonic activity of the PFM on bladder position during such tasks is
visible with USI.
BLADDER AND PELVIC FLOOR MUSCLES
85
b
Figure 3.17, cont’d b. a modifi ed leg raise.
During these manoeuvres a sagittal probe position can be used to
monitor vertical (descent) motion of the bladder, while a transverse
probe position can be employed to observe side-to-side translation.
Once the appropriate image has been generated (Figs 2.11a, 2.13a)
the probe is held still with respect to the abdomen and the patient is
asked to cough, sneeze or perform an active straight (or modifi ed)
leg raise (Fig. 3.17a, b). If there is optimal coordination of the
muscles of the region the bladder should remain relatively stationary
throughout the task. Several authors have demonstrated that a mild
degree of caudodorsal motion of the neck of the bladder occurs with
86
3 Image interpretation: qualitative
a cough or straining in both standard and patient populations (Meyer
et al 1996, Schaer et al 1999, Howard et al 2000) and therefore
should be considered normal. A straining or splinting strategy resulting in obvious caudodorsal motion of the bladder on the ultrasound
screen from a sagittal view (Fig. 3.18a), accompanied by bulging of
the lower abdomen (Fig. 3.18b), shou ld be considered abnormal and
CRANIAL
a
b
Figure 3.18 Impact of increased IAP and altered PFM function during an ASLR
test. a. Sagittal image of the bladder depicting caudodorsal motion during an
ASLR. b. Bulging
which leads t
of the abdomen (arrow) resulting from a straining strategy
o a signifi cant increase in IAP during an ASLR.
CAUDAL
BLADDER AND PELVIC FLOOR MUSCLES
indicates either a loss of support of the myofascial component of the
pelvic fl oor (a defi ciency in either the endopelvic fascia or the motor
control and/or capacity of the PFM) and/or an excessive increase in
IAP as a result of bracing activation of the diaphragm and abdominal
wall muscles (O’Sullivan et al 2002). Alternatively, signifi cant posterior motion of the bladder (detected as inferior motion of the
bladder on the ultrasound screen) is also considered non-optimal and
although the response may indicate that the excessive increase in
IAP, and excessive abdominal wall activation have been met by a
contraction of the PFM, it suggests lengthening of the fascia that
supports the bladder, which could become problematic with repetition. Furthermore, obvious lateral translation of the bladder (seen in
the transverse plane) is also abnormal and may represent either
increased contralateral oblique abdominal activity (shifts the bladder
away) or insuffi cient ipsilateral pelvic fl oor activity (fails to provide
support).
As indicated earlier, RTUS applications that involve limb motion
require diligent attention to steady the position, orientation and
inward pressure of the ultrasound probe. Failure to do so will result
in motion of the probe with respect to the body and false conclusions with regard to muscle behaviour and changes in bladder
position (Pranathi Reddy et al 2001, Whittaker 2004a). This is
particularly important in this circumstance due to the potential for
signifi cant increases in IAP and abdominal bulging. Both phenomena have the potential to thrust the probe out of the abdomen,
increasing the distance from the probe to the bladder, and produce
false motion of the bladder on the display. Consequently, a perineal
approach has been advocated as more reliable and valid by several
authors (Schaer et al 1999, Pranathi Reddy et al 2001, Thompson
et al 2005). In an attempt to control motion and maintain consistent
inward pressure of the probe (by matching the outward increase in
pressure during the task) the examiner should employ both hands,
as well as fi rmly steady their forearms on the patient’s torso and the
treatment table.
87
Preferential activation of the pelvic fl oor muscles
After observing the resting shape and monitoring the involuntary
activity of the PFM during a task that loads the spine and increases
IAP, the patient is asked to produce a voluntary, relatively isolated,
pelvic fl oor contraction using one of a variety of verbal commands.
As previously mentioned, there is a lack of evidence to suggest that
an inability to achieve this task is in anyway related to the altered
involuntary motor control identifi ed in the literature with regard
to individuals with LBP. However, there is evidence that links an
inability to produce an isolated contraction of the PFM with the
88
3 Image interpretation: qualitative
presence of incontinence (Hay-Smith et al 2001). Clinically, the
purpose of the task is to assess the ability to access the specifi c
neurological pathways to these muscles.
It is critical to realize that preferential activation evaluates many
factors beyond the health of the motor control pathways. For
instance the individual’s ability and motivation to learn, as well as
the ability of the therapist to instruct, will have an infl uence on
the success of this task (Thompson & O’Sullivan 2003, Hodges
2005a). Hence, there is no magical cue that will elicit the correct
contraction. Some common clinical cues include (adapted from Lee
2004):
●
‘Slowly and gently contract the muscles in an attempt to slow
your fl ow of urine’.
●
‘Slowly and gently drawing your vagina (or testicles) up into
your body’.
●
‘Slowly and gently think about closing your rear passage (anus)’.
●
‘Slowly and gently draw your lower abdominal wall in towards
your spine’.
Clinical experience suggests that providing basic guidance about
the anatomical location of the PFM in addition to a verbal command
is benefi cial, as there appears to be a signifi cant number of individuals that confuse their lower abdominal region with their pelvic
fl oor, and a posterior pelvic tilt with a PFM contraction.
Defi nition of an isolated pelvic fl oor muscle contraction
The bladder is supported by the PFM and the endopelvic fascia
(Aston-Miller et al 2001, Williams 1995). When the midline PFM
(pubococcygeus and iliococcygeus) contract they broaden, increase
the tension of the endopelvic fascia, and produce encroachment of the
bladder wall. This is normally refl ected as a slow indentation isolated
to the caudodorsal aspect of the bladder wall, accompanied by a
cranioventral lift of both the neck and body of the bladder (Bø et al
2001, Christensen et al 1995, Howard et al 2000, Pranathi Reddy
et al 2001, Whittaker 2004a) (Figs 3.19a, b and 3.20a, b).
The indentation of the caudodorsal aspect of the bladder wall
can be observed in both the sagittal (Bø et al 2003, Thompson &
O’Sullivan 2003, Whittaker 2004a, Thompson et al 2005, 2006a)
and transverse (Whittaker 2004a, Sherburn et al 2005) planes;
however, Christensen et al (1995) suggest that displacement is most
easily observed from the sagittal perspective. Clinically, as the
response of the PFM is often asymmetrical there is value in screening the contraction from both planes. The sagittal view allows for
analysis of cranioventral motion, whereas the transverse view allows
for evaluation of the side-to-side symmetry of the contraction. If
the patient can demonstrate an isolated contraction of the PFM they
CRANIAL
BLADDER AND PELVIC FLOOR MUSCLES
BLADDER
89
a
BLADDER
b
Figure 3.19 USI of the bladder and pelvic fl oor muscles (sagittal) – preferential
activation. a. Resting ultrasound image of the bladder, vaginal wall (dotted line)
and pelvic fl oor. b. An isolated response of the midline PFM; note the isolated
indentation as the
(arrow).
vaginal wall is lifted into the caudodorsal aspect of the bladder
CAUDAL
VENTRAL
DORSAL
90
3 Image interpretation: qualitative
a
LEFT RIGHT
BLADDER
CRANIAL
BLADDER
b
Figure 3.20 USI of the bladder and pelvic fl oor muscles (transverse) –
preferential activation. a. Resting ultrasound image of the bladder.
b. An isolated response of the midline pelvic fl oor muscles; note the isolated
indenta
tion of the caudaldorsal aspect of the bladder (arrow).
CAUDAL
are asked to repeat the contraction and hold it while breathing
normally. Concurrently, the examiner palpates for a co-contraction
of TrA and dMF (Figs 3.8, 3.14) (Sapsford & Hodges 2001). This
will establish the endurance capacity of the PFM, as well as their