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Le-Anne Grimshaw,
Chief Sonographer,
Mater Imaging, North Sydney,
Lecturer Musculoskeletal
Sonography and Advancements in
Ultrasound, Curtin University, WA
Ultrasound for athletic pubalgia
Dear Expert,
I am scanning an increasing number of young sports people with groin pain. What pathology might I expect to
see in the absence of a hernia?
Introduction
Athletic pubalgia is the term given to groin
pain experienced while playing sport.
It is also called groin strain, sportsman’s
hernia, Gilmore’s groin, athletic hernia
and groin disruption. It is commonly
seen in sports that involve side-toside cutting, quick accelerations and
decelerations, and sudden directional
changes and often observed in players
of soccer, AFL, ice hockey, field hockey
and tennis. However, athletic pubalgia is
not confined to elite athletes and is found
in school athletes and weekend warriors.
Pain can range from mild episodes of
discomfort to chronic career-ending pain.
It is vital to diagnose the exact source of
the injury so it can be treated effectively
as, if misdiagnosed, the wrong exercises
can exacerbate the irritation.
Almost 20% of all sports injuries are
related to the groin [1–4]. Athletic pubalgia
Table 1. Areas affected by athletic pubalgia
1. Anterior hip joint
Rectus femoris, sartorius, tensor
2.
fascia lata (TFL)
3. Iliopsoas tendon
4. Pubis – pubic tubercle
5. Adductor longus
Common rectus abdominis –
6.
adductor origin
7. Conjoint tendon
8. Inguinal ligament
Rectus abdominis, external
9. oblique, internal oblique, transverse
abdominis muscles
10. Ilioinguinal nerve
Inguinal and femoral canals and
11.
rectus sheath
18 soundeffects
is the third highest cause of injury
leading to time off the playing field, after
fractures and anterior cruciate ligament
reconstructions [3]. It is a frustrating
injury, often intermittent and poorly
localised. It can be difficult for the clinician
to pinpoint the exact nature of the injury
and therefore is difficult to treat.
Groin pain in sports people is usually
clinically diagnosed as an inguinal hernia
or adductor strain. However, tendinous and
ligamentous pathologies centred around the
pubic tubercle are the most common cause
of groin pain, with muscle strains and tears
and nerve entrapment syndromes also to
be considered. Table 1 lists the areas that
can be imaged with ultrasound in a patient
with athletic pubalgia. The ultrasonic
anatomy and pathology of these structures
will be reviewed. For the purpose of this
paper, inguinal, femoral and spigelian
hernias will not be discussed.
Clinical presentation
The player may experience sudden and
acute pain while on the playing field
or there might be an insidious onset
of pain that is poorly localised. The
pain may be centred over the conjoint
tendon and inguinal canal or it may
radiate to the adductor region and into
the scrotum/labia. It may increase with
sudden movements such as coughing,
sneezing, or performing a resisted sit
up [5]. There can often be more than
one pathology causing the pain. For
external
oblique
muscle
rectus abdominus
muscle
internal
oblique
muscle
transverse
abdominus
muscle
ilioinguinal nerve
conjoint tendon
hip joint
inguinal
ligament
lesser trochanter
iliopsoas insertion
spermatic cord
adductor origin
attachment
Fig 1. Anatomy of the pelvis showing the relationship of the structures mentioned in Table 1 [12]
Ultrasound for athletic pubalgia
example, it would not be unusual to have
adductor tendinopathy, osteitis pubis
and a sportsman’s hernia coexisting.
This makes the clinical diagnosis even
more problematic.
Conservative treatment is not always ideal
for these people, particularly in the elite
sports person who wants to get back to
the playing field as soon as possible [5].
Ultrasound is an excellent tool for
diagnosing the pathology listed
in Table 2. When performing the
ultrasound, it is important to always
scan the contralateral side and to use
a clinician’s touch while scanning.
For the ultrasound examination, the patient
lies supine on the table with the legs
comfortably extended and is asked to
identify the area of pain. In some instances,
they may move their leg or perform a sit up
to attempt to elicit the pain to further target
the exact region of soreness.
The anatomy, scanning technique and
ultrasonic pathological appearances
of the causes of athletic pubalgia,
Table 2. Pathology that may cause athletic
pubalgia
Adductor longus dysfunction
Osteitis pubis
Posterior inguinal wall deficiency
Hip joint pathology
Labral tears
Femoro-acetabular impingement
Tendinosis or tears of any of the following
muscles:
Rectus abdominis, rectus femoris,
sartorius, tensor fascia lata (TFL)
Nerve entrapment syndromes –
Ilioinguinal nerve
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as outlined in Tables 1 and 2, will
be discussed.
Anterior hip joint
The hip joint is a ball and socket joint and
is covered by a homogeneous, echogenic
triangular-shaped labrum. The entire joint
is then covered with a fibrous capsule
containing multiple ligaments that attach
distally to the neck of the femur [8].
To image the hip joint, the ultrasound
probe is positioned in a longitudinal plane
over the anterior groin crease (fig 2).
Pathology
An intra-articular joint effusion may be
seen at the level of the femoral neck
where fluid displaces the ligaments
anteriorly. Comparison with the normal
contralateral side will show a difference in
the capsular thickness (fig 3). A difference
of 2 mm or more is suggestive of a
significant joint effusion [10]. Martinoli
also suggests an increased thickness
of the joint capsule greater than 7 mm
is indicative of a joint effusion [11].
Labral tears are seen as anechoic defects
in the labrum (fig 4). Paralabral cysts may
also be identified which are a secondary
sign of a tear [9].
Loose bodies are echogenic foci seen
within the joint and can be large enough
to cause impingement and pain with
hip movements.
Labral ossicles are exostoses of bone
that can cause femoroacetabular
impingement and pain (fig 4).
B
Figs 3A and 3B. Longitudinal image of the femoral neck (callipers).
(A) joint effusion with bulging of the ligaments and an increased
measurement. (B) normal femoral neck image
A
Fig 2. Photograph showing positioning of
the transducer for the anterior hip joint
with the patient lying supine and the legs
comfortably relaxed
Rectus femoris, sartorius
and tensor fascia lata
muscles
The rectus femoris muscle has a broad
attachment onto the anterior inferior
iliac spine (AIIS) and ilium superior to
the acetabulum [8]. To image the rectus
femoris origin, from the anterior hip joint
position, the probe is moved slightly
superiorly.
The sartorius muscle attaches proximally
to the anterior superior iliac spine (ASIS)
and courses immediately medially to insert
distally onto the proximal, medial portion
of the tibia [8]. Position the transducer
transversely over the ASIS and move
it inferiorly. The sartorius is seen as it
moves medially across the hip joint.
The tensor fascia lata (TFL) muscle has
a thin tendinous insertion onto the lateral
portion of the ASIS and then blends with
the iliotibial band that then attaches to the
lateral condyle of the tibia [8]. It is best
B
Figs 4A and 4B. Longitudinal images of the hip joint. (A) shows a
labral ossicle as an echogenic linear structure in the labrum. (B) tear
of the labrum (callipers)
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Ultrasound for athletic pubalgia
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scanned with the patient lying on their side.
The probe is placed in a longitudinal plane
over the ASIS with the depth reduced to
about 3–4 cm to assess the tendinous
insertion onto ASIS and then increased to
visualise the muscular component.
Pathology
A muscle strain on ultrasound appears
as increased echogenicity of the muscle.
It can be focal or diffuse (fig14).
A partial tear in a muscle may be
intrasubstance – along the fibres of the
muscle where a linear hypoechoic or
anechoic cleft is seen in a thickened
muscle.
A full thickness tear is seen as a defect
that traverses the entire width of the
muscle. Heterogeneous or anechoic
haematoma may be seen to fill the gap
of the defect (fig 5).
Iliopsoas tendon
The iliopsoas is comprised of the psoas
major, psoas minor and iliacus muscles.
The distal tendon insertion is onto the
lesser trochanter of the femur [8]. This
is best visualised on ultrasound with the
patient’s knee flexed and hip abducted
(fig 6). Starting with the probe in a
longitudinal plane over the anterior hip
joint, it is then moved slightly medially
where the tendon of the iliopsoas is seen
crossing the joint. Keeping the tendon
in view, slide the probe inferiorly and
slightly medially to the lesser trochanter.
This tendon should also be imaged
dynamically in transverse at the level
of the hip joint to check for a snapping
iliopsoas tendon. The tendon should glide
smoothly over the iliopectineal eminence
as the patient straightens the leg.
Pathology
Snapping iliopsoas
The iliopsoas tendon can become
enlarged and tendinopathic as it
‘bumps’ over a prominent iliopectineal
eminence. The tendon is scanned in a
transverse orientation over the hip joint
with the patient’s leg abducted and
flexed and then watch the movement
of the iliopsoas tendon as the patient
straightens and extends the leg. The
patient will complain of feeling a click
over the anterior hip joint. This click will
also be felt and seen during the dynamic
scan. As the patient straightens the leg,
the tendon will have a jerky motion
instead of a smooth glide.
Iliopsoas bursitis
This is a distension of the bursa
around the iliopsoas tendon. This is
an inflammatory condition caused by
excessive flexion and extension in
athletes [7]. On ultrasound, the tendon
may appear thickened and there will be a
hypoechoic collection around the tendon,
often medially. A curvi-linear probe may
demonstrate the bursitis more clearly and
can be used for injections into the bursa
as it may display the needle more clearly.
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portion of this is the pubic crest. Pubic
tubercles arise from the lateral end of
each side of the crest [8].
The transducer is positioned in a
transverse orientation directly over
the pubic bones.
Pathology
Osteitis pubis may be seen on X-ray
as erosions at the subchondral bone
on either side of the symphysis. These
bony irregularities will also be seen on
ultrasound along with thickening and
hypertrophy of the joint capsule and
ligaments (fig 7). It often coexists with
rectus abdominis-adductor dysfunction.
Pubis
Adductor longus
The inferior part of the pelvis is formed
by the pubis anteriorly and the ischium
posteriorly. The pubis is divided into the
body and two rami. The right and left
pubic bodies are joined by the strong
fibrous symphysis pubis. The superior
The adductor longus attaches to the body
A
Fig 5. Longitudinal image of TFL insertion
with a full thickness tear of the tendon
(calipers)
Fig 6. Photograph showing positioning of
the patient and the transducer for iliopsoas
tendon imaging in long
of the pubis inferior to the pubic crest [8].
Pathology
Adductor longus dysfunction can be a
precursor to osteitis pubis. Bony erosions
B
Figs 7A and 7B. Image over the pubis. (A) normal smooth delineation of the pubic crest
either side of the hypoechoic symphysis pubis. (B) osteitis pubis with irregular bony surface
of the pubic bones, which was also very tender with probe pressure
Ultrasound for athletic pubalgia
A
Fig 8. X-ray of a pelvis showing the anatomical
insertions of rectus abdominus and adductor longus
(red), conjoint tendon (blue) inguinal ligament (green)
and the common rectus abdominis – adductor origin
(white)
Pathology
origin onto the pubis. There may be pain
Tendinopathy of the origin will
demonstrate increased thickness
and heterogeneity compared to the
contralateral side and will be tender
with probe pressure (fig 9). It can be
in isolation or can be associated with
osteitis pubis and adductor tendinopathy
(fig 10).
The transducer is pressed up against
the inferior portion of the pubis in a
longitudinal plane. The patient may
abduct the leg slightly to allow better
access to the adductor origin.
Adductor tendinopathy is seen on
ultrasound as a thickened, heterogeneous
tendon origin with bony irregularity that is
tender to press (fig 10).
Partial tearing of the origin and/or muscle
may be seen as discrete anechoic clefts.
There may be multiple tears seen.
A full thickness tear of adductor longus
will demonstrate retraction of the muscle
with haematoma filling the gap in the
acute phase.
Common rectus abdominis
– adductor origin
The rectus abdominis muscle inserts
from a superior course onto the pubic
tubercle and the adductor tendon
inserts from an inferior course onto
the pubic tubercle. The two tendon
insertions merge to form a common
origin (fig 8). To image the common
rectus abdominis – adductor origin, the
transducer is positioned in a longitudinal
plane with the mid part of the probe
resting on the pubic tubercle, slightly to
the left and then right of the midline.
review
B
Fig 9. Image of the common rectus abdominis – adductor origin, in long. (A) when
the probe is placed on the right pubic tubercle over the common rectus abdominus –
adductor origin the pain was extreme and localised. The common origin is thicker and
heterogeneous compared to the contralateral normal side in image (B)
can be seen on ultrasound at the tendon
with probe pressure.
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Conjoint tendon
The conjoint tendon is the aponeurosis
of the internal oblique and transverse
abdominis muscles which form the roof
and posterior wall of the inguinal canal [8].
Pathology
Sportsman’s hernia
Inflammation of the conjoint tendon and
periostium at the adductor origin causes
the tendon to thicken up and lose its
elasticity. This leads to posterior inguinal
wall deficiency where the wall is displaced
anteriorly rather than becoming taut
when the patient strains. On ultrasound,
the conjoint tendon appears thicker and
the inguinal canal loses its ‘bounce’ with
straining (fig 11). Instead of the inguinal
canal going from a horizontal position
at rest to a vertical position on strain,
the canal remains horizontal with little
movement (fig 12). This condition often
It has always been thought to attach
onto the pubic crest. However, new fresh
cadaveric research has shown that this
aponeurosis may instead merge into the
anterior sheath of the lateral aspect of
rectus abdominis (fig 8) [7].
coexists with osteitis pubis and adductor
To image the conjoint tendon, first find the
internal oblique and transverse abdominis
muscles in a transverse plane at the level
of the ASIS. Follow the two muscles
distally. As you slide the probe inferiorly,
the muscles will reduce in size eventually
joining to form the conjoint tendon. Rotate
the probe so it is running along the length
of the conjoint tendon. This is seen as
an echogenic thin band that merges with
the rectus abdominis, which then in turn
attaches to the pubic crest.
Inguinal ligament
Always image both sides in a dual format
to better compare size and echogenicity
of this structure.
tendinosis. It is thought excessive
adductor action creates shearing forces
across the pubic symphysis that stress
the posterior inguinal wall, resulting in
posterior inguinal wall deficiency [5].
The inguinal ligament is the aponeurosis
of the external oblique muscle and is seen
as a fibrous band between the ASIS and
the pubic crest (fig 8). It forms the floor
and anterior wall of the inguinal canal [8].
From the common rectus abdominis –
adductor position, the superior part of
the transducer is rotated towards the iliac
crest. The ligament is a thin, 2 mm linear
fibrillar structure seen coursing between
the ASIS and the pubic crest. In men,
the spermatic cord can be seen crossing
over the distal end of the ligament.
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A
Fig 10A. Transverse image of the pubis.
Unilateral osteitis pubis with common rectus
abdominis – adductor origin tendinopathy and
associated adductor tendinopathy
Pathology
Repeated stretching or sudden force can
lead to injury to the inguinal ligament. The
ligament appears thicker and hypoechoic
on ultrasound when compared to the
contralateral side, and is often tender
with probe pressure (fig 13).
Rectus abdominis, external
oblique, internal oblique
and transverse abdominis
muscles
The rectus abdominis originates from
the pubic crest and pubic symphysis
and extends superiorly and longitudinally
to the xiphoid process and 5th and 7th
costal cartilages [8].
The external oblique, internal oblique
and transverse abdominis muscles are
the flat anterolateral abdominal muscles
that support the anterolateral abdominal
wall, maintaining posture and exerting
firm pressure on the visceral organs,
protecting them from injury [8].
C
B
Figs 10B and 10C. Longitudinal image of the adductor origin. Same patient as fig 11A.
(B) irregular bony margin of pubic crest with associated thickening and heterogeneity of
common rectus – adductor origin and adductor tendinopathy. (C) image of the contralateral
normal side showing normal pubic crest and adductor origin
A
B
Figs 11A and 11B. Images of the conjoint tendon in long (calipers) in a 23-year-old soccer player
with ongoing, perplexing groin pain. (A) thickened conjoint tendon compared to the normal
tendon in (B). The thickened conjoint tendon resulted in a sportsman’s hernia in this patient
A
B
C
D
Pathology
Any of these muscles are susceptible
to strains, partial and full thickness tears,
as has been described previously. Partial
thickness tears in these muscles are
often seen to affect the deeper portion of
the muscle. A hypoechoic thickening will
be visualised on ultrasound.
Ilioinguinal nerve
Figs 12A-12D. Images of the inguinal canal in cross section at rest (A), (C) and with the
patient straining (B), (D). The patient in (A) and (B) has a sportsman’s hernia. The conjoint
tendon is thickened and the canal remains in a horizontal plane at rest and with the
patient straining. The inguinal canal (C) and (D) is normal showing the canal moving from
a horizontal plane to a more vertical orientation
The ilioinguinal nerve courses between
the internal oblique and transverse
abdominis muscles (fig 1), from the
ventral ramus of the first lumbar nerve
to the scrotum/labia [8]. It also supplies
the medial thigh. It is therefore not
unusual for the patient to complain of
pain into the testicle and/or the proximal
medial thigh over the adductor muscles.
Ilioinguinal nerve entrapment is a good
explanation for generalised, poorly
targeted groin pain.
22 soundeffects
Position the transducer transversely
over the internal oblique and transverse
abdominis muscles at the level of the ASIS
and slide the probe obliquely towards the
pubis. The nerve and artery will be seen
running in the fascia between these two
Ultrasound for athletic pubalgia
A
B
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B
A
C
D
Figs 13A and 13B. Image of the inguinal ligament (cursors) at the level
of the pubic tubercle. (A) Normal inguinal ligament. (B) The patient
was point tender over the left pubic tubercle. The insertion of the
inguinal ligament onto the pubic bone on the left is thickened with
Figs 14A–14D. Images of the rectus abdominis muscle. Normal
fluid overlying it. An avulsion fracture is seen deep to the ligament
echogenicity seen in the transverse (A) and longitudinal (C) images.
Increased echogenicity indicating a muscle strain in (B) and (D)
muscles. Use colour Doppler to identify
the artery adjacent to the nerve (fig 15).
Pathology
Ilioinguinal nerve entrapment
Irritation of the ilioinguinal nerve may be
a precursor to general groin syndromes.
Repetitive sprinting, turning and kicking
may excessively load and stretch the
psoas and abdominal muscles causing
irritation of the nerve [6].
The nerve appears thickened on
ultrasound compared with the
contralateral side (fig 15). It can be tender
with probe pressure over the nerve.
Conclusion
When scanning a patient who presents
with groin pain, the ultrasound
examination should start with a hernia
study. If no inguinal, femoral or spigelian
hernia is identified, then the ultrasound
should be extended to include the
tendons, nerves and musculature around
the groin, particularly around the pubic
A
tubercle. Correct diagnosis of common
rectus abdominis – adductor tendinosis
or ilioinguinal nerve entrapment, for
example, assists greatly with treatment
and can help to shorten the time out of
sport and speed up recovery time.
Acknowledgements
5. Edell D: Athletic Hernias. [Internet] 2009.
Updated 24-10-2009; cited Jan 2013.
Available from www.athleticadvisor.com
/injuries/general_inj/athletic_hernias.htm
6. Mallac C. Groin Strain. Sports Injury
Bulletin. [Internet] 2009. Updated
2009;cited Dec 2012. Available from
www.lollylegs.com/images/groin.jpg
I would like to thank Sally Bateman for
her assistance with the anatomy diagram
in this article.
7. MacMahon P, Hogan B, Shelley M,
Eustace S, Kavanagh, E. Imaging of Groin
Pain. Magnetic Resonance Imaging Clinics
of North America. 2009;17(4).
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Lach J. Sports hernias: a systematic
literature review. Br J Sports Med.
2008;42:954–964.
8. Moore K, Dalley A. Clinically Oriented
Anatomy – Fourth Edition. Lippincott,
Williams and Wilkins; 1999.
2. Koulouris G. Imaging review of groin pain
in elite athletes: an anatomic approach to
imaging findings. AJR. 2008;191(4):962–
972. Available from www.ajronline.org
/content/191/4/962.full
3. Robinson P, Bhat V, English B. Imaging
in the assessment and management
of athletic pubalgia. Seminars in
Musculoskeletal Radiology. 2011;15(1).
4. Morelli V, Weaver V. Groin injuries and groin
pain in athletes: part 1. Prim Care Clin
Office Pract. 2005;32:163–83.
B
9. Marshall N, Koulouris G. Traumatic Injuries
of the Hip. Magnetic Resonance Imaging
Clinics of North America. 2009 Nov;17(4).
10. Van Holsbeeck M, Introcaso J.
Musculoskeletal Ultrasound Second
Edition. Mosby; 2001.
11. Bianchi S, Martinoli C. Ultrasound of the
Musculoskeletal System: Springer;2007.
12. Netter FH. 2006. Atlas of Human Anatomy.
4th edn. Philadelphia Saunders Elsevier.
C
Figs 15A-15C. Images of the ilioinguinal nerve in transverse between the internal oblique and transverse abdominus muscles. (A) Normal
ilioinguinal nerve N with the artery A and vein V adjacent in colour. (B) shows thickened ilioinguinal nerve. (C) is a colour Doppler image
showing colour in the adjacent blood vessel. Note the echogenic fibrosis surrounding the abnormal nerve in (B) and (C)
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