1. Dr/ ABD ALLAH NAZEER. MD
Ultrasound examination of the knee joint.

2. ULTRASOUND OF THE KNEE – Normal.
Transverse scan plane
for the quadriceps
Transverse suprapatella region:
•RF: Rectus Femoris •VI: Vastus intermedius
•VL: Vastus Lateralis •VM: Vastus Medialis

3. Suprapatellar scan plane.
Longitudinal suprapatella region showing the
suprapatella bursa and quadriceps tendon.

4. Prepatellar scan plane.

5. Infrapatellar scan plane.
The infrapatellar tendon.
Also called the patella ligament.

6. The insertion of the infrapatellar tendon
onto the tibial tuberosity. Note: The
normal physiological amount of fluid
along the underside of the tendon.
Transverse Infrapatellar tendon. Note how
wide it is, to then have an understanding of
the area you need to examine in longitudinal.

7. Pes anserine scan plane.
The Pes Anserine bursa and tendon insertion
are medial to the Infrapatellar tendon on the
tibia, adjacent to the MCL insertion.
Remember the Pes Anserine tendons
as (sargent) SGT: Sartorius, Gracilis
and semi-Tendinosis.

8. Medial knee joint scan plane.
The medial collateral ligament (green) directly
overlying the medial meniscus (purple).

9. Lateral knee joint scan plane.
Assess the Lateral collateral ligament, Ilio-Tibial
band insertion and peripheral margins of the
lateral meniscus. Unlike the medial side, the LCL is
separated from the meniscus by a thin issue plane.

10. Ilio-Tibial Band.
Rotate the probe off the LCL with the toe
of the probe angled slightly posteriorly.

11. Popliteal fossa scan plane.
Medial aspect of the popliteal fossa showing
the semimembranosis/gastrocnemius plane.

12. Ultrasound of the Popliteal vein and
artery in transverse. Without and
with compression to exclude DVT.
Confirm both arterial and venous flow
and exclude a popliteal artery aneurysm

26. ROLE OF ULTRASOUND
Ultrasound is essentially used for the external structures of the knee. Ultrasound is
a valuable diagnostic tool in assessing the following indications; Muscular,
tendinous and ligamentous damage (chronic and acute) Bursitis Joint effusion
Popliteal vascular pathology Haematomas Masses such as Baker’s cysts, lipomas
Classification of a mass e.g solid, cystic, mixed Post surgical complications e.g
abscess, edema Guidance of injection, aspiration or biopsy Relationship of normal
anatomy and pathology to each other Some boney pathology
LIMITATIONS
It is recognised that ultrasound offers little or no diagnostic information for
internal structures such as the cruciate ligaments. Ultrasound is complementary
with other modalities, including plain X-ray, CT, MRI and arthroscopy.
EQUIPMENT SELECTION AND TECHNIQUE
Use of a high resolution probe (7-15MHZ) is essential when assessing the
superficial structures of the knee. Careful scanning technique to avoid anisotropy
(and possible misdiagnosis) Beam steering or compounding can help to overcome
anisotropy in linear structures such as tendons. Good colour / power / Doppler
capabilities when assessing vessels or vascularity of a structure. Be prepared to
change frequency output of probe (or probes) to adequately assess both
superficial and deeper structures.

27. SCANNING TECHNIQUE
POSTERIOR FOSSA
Patient prone on bed, knee flexed slightly with a pad under the ankle for support.
Survey the entire fossa to identify the normal anatomy, including; Popliteal artery
and vein (patency. aneurysm, thrombosis) Posterior joint (joint effusion) Medial
popliteal fossa [ bursa between semi-membranosis tendon and medial
gastrocnemius muscle] (Baker’s cyst) Document the normal anatomy and any
pathology found, including measurements and vascularity if indicated.
ANTERIOR KNEE
Patient lies supine on bed with knee flexed 20 - 30 degrees. Alternatively patient
may sit on the side of a raised bed with foot resting on Sonographers knee for
support. Identify the normal anatomy, including: Quadriceps tendon (tears, M/T
junction, tendonitis) Suprapatella bursa (bursitis-simple/complex, synovial
thickening, loose bodies) Patella (gross changes e.g erosion, bipartite, fracture)
Patella tendon (tears, tendonitis, insertion enthesopathy) Infrapatellar bursa
(tendinosis, tears, bursitis, fat pad changes) Infero-Medial - Pes anserine bursa.
LATERAL AND MEDIAL KNEE
May be scanned as above. Assess the medial and Lateral Collateral ligaments and
meniscal margins. Joint lines (ligament tears or thickening, meniscal
bulging/cysts, joint effusion, gross bony changes).

28. BASIC IMAGING
A knee series should include the following minimum
images;
Quadriceps tendon - long, trans +/- MT junction
Suprapatellar bursa
Pre patellar - long
Patella tendon - long, trans, insertion onto tibial
tuberosity
Medial meniscus and MCL
Lateral Meniscus and LCL
Popliteal artery and vein to demonstrate patency
Medial popliteal fossa
Document the normal anatomy and any pathology found,
including measurements and vascularity if indicated.

29. “Jumper’s knee” or patellar tendinosis
is a common condition affecting athletes with an incidence in this
subpopulation of 13% to 20%. It is particularly prevalent in sports
involving jumping and heavy landing, rapid acceleration or
deceleration and kicking, such as basketball, volleyball, soccer,
tennis, long jump and high jump. It has a tendency to become
chronic and, in elite athletes, the incidence of having to retire from
their sport is as high as 53%.
Imaging:
Both ultrasound and MRI have been described for the diagnosis of
patellar tendinosis. Ultrasound has traditionally been used to image
tendons and reveals consistent findings in patellar tendinitis. The
tendon reveals an area of hypoechoic signal change and increased
thickness corresponding to the area of clinical tenderness. Colour
Doppler examination is a useful adjunct as it has been shown to
identify vascularity and neovessels in the area of structural change.

30. Patellar tendinopathy. Longitudinal ultrasound scan along the
anterior aspect of the knee joint shows thickened tendon .

31. Patellar tendinopathy with thickened distal patellar tendon
longitudinal with increased vascularity.

32. Tendinosis of the distal patellar tendon insertion with neovascularity and slightly thickened bursa.

33. US show partial thickness tear of the quadriceps tendon.

34. A sagittal image of the affected left knee demonstrates the ruptured quadriceps
tendon (T) attached to the superior pole of the patella (P). Note the loss of linear fibers
of the tendon, which is filled in by an effusion (*) anterior to the distal femur (F)

35. The prepatellar bursa is a superficial bursa with a thin synovial lining
located between the skin and the patella. Normally, it does not
communicate with the joint space and contains a minimal amount of fluid;
however, inflammation of the Prepatellar bursa results in marked increase
of fluid within its space.
Prepatellar bursitis is often caused by pressure from constant kneeling.
Plumbers, roofers, carpet layers, coal miners, and gardeners are at greater
risk for developing the condition.
A direct blow to the front of knee can also cause prepatellar bursitis.
Athletes who participate in sports in which direct blows or falls on the
knee are common, such as football, wrestling, or basketball, are at greater
risk for the condition.
Musculoskeletal ultrasound is emerging as a viable imaging modality to
assess the knee joint. Advantages include its ease of availability, economic
savings compared to MRI, ability to easily compare abnormalities to the
contralateral side, demonstration of fibrillar microanatomy of tendons,
ligaments, and muscles, and the ability to compress and dynamically
assess structures. Musculoskeletal ultrasound can be utilized to distinguish
difficult cases of joint effusion from that of bursal swelling.

36. Prepatellar bursitis. Longitudinal midline ultrasound scan shows distension of the
Prepatellar bursa with a sonolucent fluid collection with coarse internal echoes.

37. Ultrasound prepatellar bursitis (a) and a septal pattern (b)

38. Prepatellar bursitis with thickened hypoechoic bursa anterior of the patellar tendon.

40. Osgood-Schlatter disease (OSD) is a chronic fatigue injury
due to repeated microtrauma to involving the patellar
ligament insertion onto the tibial tuberosity.
Ultrasound
Ultrasound examination of the patellar tendon can depict
the same anatomic abnormalities as can plain
radiographs, CT scans, and magnetic resonance images.
The sonographic appearances in Osgood-Schlatter disease
include:
swelling of the unossified cartilage and overlying soft
tissues fragmentation, and irregularity of the ossification
center with reduced internal echogenicity
thickening of the distal patellar tendon
infrapatellar bursitis.

41. Osgood Schlatter on both sides with cartilage swelling and fragmentation of the apophysis.

42. Osgood Schlatter disease with irregular apophysis and infrapatellar bursitis and tendinosis

43. Osgood schlatter disease with irregular apophysis and infrapatellar bursitis and
tendinosis with a hypervascularized inhomogeneous patellar tendon

44. Osgood schlatter disease with cartilage swelling and irregular apophysis
and thickened hypervascularized inhomogeneous patellar tendon.

45. Medial collateral ligament (MCL) and lateral collateral ligament
(LCL) injuries of the knee are common. In fact, injury to the MCL is
the most common ligamentous knee injury.
The MCL and LCL provide restraint to valgus and varus angulation
of the knee, respectively. The MCL has superficial and deep
components. The superficial MCL fibers attach proximally to the
medial femoral epicondyle and distally to the medial aspect of the
tibia, approximately 4 cm distal to the joint line. The deep MCL
fibers originate from the medial joint capsule and are attached to
the medial meniscus.
The LCL is part of a complex of ligaments collectively named the
posterolateral corner (PC). The structures in the PC include the
LCL, the popliteofibular ligament, the popliteus ligament, the
arcuate ligament, the short lateral ligament, and the posterolateral
joint capsule. The LCL is separated from the lateral meniscus by a
fat pad. All injured collateral ligament structures were thickened and
heterogeneously hypoechoic. Ultrasonography is useful in evaluating
isolated collateral ligament injuries and in predicting patient outcome on
the basis of the location of the collateral ligament injuries.

46. Partial thickness tear of the medial collateral ligament with an inhomogeneous thickened ligament

47. Full thickness medial collateral ligament rupture.

48. Medial collateral ligament injury. Longitudinal scan along the medial aspect of the knee
shows thickened medial collateral ligaments with a hypoechoic area denoting acute injury.

49. Chronic medial collateral ligament injury with a thickened
inhomogeneous ligament intratendinous fissure and neovascularity.

50. Lateral collateral ligament injury. Longitudinal scan along the lateral aspect of the knee
joint shows a heterogeneous mass replacing the LCL and displacing the biceps tendon
anteriorly. The mass represents a hematoma and denotes acute injury.

51. Cystic lesions in the medial collateral ligament caused by friction over a bony spur.

52. Medial collateral ligament acute tear.

53. Ultrasonography of a meniscal tear encompassed a static
observation of a hypoechogenic area and a dynamic appreciation
of meniscal extrusion. The extrusion of the meniscus when torn
depended on a disruption of the ultra structure and hence function
of the meniscus. In the presence of a tear the intrinsic stability of
the meniscus on loading is lost and this can be detected.
The accuracy of ultrasonography by its sensitivity of 86.4%, which
matched that of MR scanning, supports its use in the diagnosis of
meniscal tears. Given the rapidity with which the investigation
can be conducted and the relative lack of expense it is a good
investigation for use in a ‘one-stop’ clinic. Before routine use of
ultrasonography in the diagnosis of meniscal tears, further
improvement is required to address the problem of false-positive
results which could lead to inappropriate surgery being
performed. The ultrasound to be less specific during the earlier
disease stage.

54. Meniscal injury. (A) Ultrasound scan along the medial aspect of the knee
joint shows a swollen meniscus with a linear hypoechoic cleft denoting
meniscal degeneration. (B) Sonogram of the lateral aspect of the knee
joint shows a hypoechoic meniscal cyst connected to a meniscal tear.

55. Medial meniscal tear: (a) Coronal T1-weighted magnetic resonance imaging, (b) ultrasound

56. Medial meniscal tear.

57. Horizontal lateral meniscus rupture and meniscal cyst.

58. Medial meniscal protrusion and small rupture.

59. Meniscal degeneration with protrusion of the lateral meniscus with cysts and
bulging of the lateral collateral ligament

60. Large medial meniscal cyst and medial meniscal rupture.

61. Lateral meniscal cyst extending under the patellar tendon.

62. Large cyst at the base of the meniscus in 6 year old child.

63. The anterior cruciate ligament (ACL) is an intra-articular structure that
originates at the medial wall of the lateral femoral condyle posteriorly and
inserts into the intercondylar area of the tibia. The ACL is the primary
restraint to anterior displacement of the tibia relative to the femur and
acts as a restraint to internal–external rotation.
The sonographic appearance of the ACL was a hypoechoic band with a
diameter of 7.3 mm.
Magnetic resonance imaging (MRI)
and sonographic images of the
anterior cruciate ligament (ACL) in a
normal individual. (A) Sagittal T2-
weighted MRI of the right knee with
90° flexion. The decreased T2 signal
ACL is within the frame (arrowheads).
(B) MRI of the ACL: 135° clockwise
rotation and magnification of the
frame in (A). (C) Sonographic image
of the ACL, showing a hypoechoic
band in comparison with the MRI
image. Arrowheads = ACL; F = femur;
P = patella; T = tibia.

64. Arthroscopic and sonographic image of an intact anterior cruciate ligament
(ACL). (A) Arthroscopic ACL image. (B) Sonographic image of an intact ACL
under arthroscopic guidance. Between the black and white arrowheads is
the ACL; white arrow indicates the Kelley. P = patella; T = tibia.

65. Magnetic resonance imaging and
sonographic images of an individual with
a ruptured left anterior cruciate ligament
(ACL). (A,B) Magnetic resonance imaging
and (C,D) sonographic images of a subject
with (A,C) an intact right and (B,D) a
ruptured left ACL. (E,F) Dynamic
sonographic image of the ACL when
individuals rotate their tibia internally or
externally.(A) Black arrowheads indicate
intact ACL with diameter of 6.4 mm. (B)
Black arrow indicates ruptured ACL with
a thinner diameter. (C) Between the white
arrowheads is the intact ACL appearing as
a hypoechoic band. (D) White star
indicates ruptured ACL with a heteroechoic
appearance. (E) The soft tissue above the
ACL moves in the opposite direction to the
ACL movement in normal individuals. (F)
The soft tissue above the ACL moves in the
same direction as the ACL movement in
individuals with a torn ACL. F = femur; P =
patella; T = tibia.

66. The ultrasound role of posterior cruciate ligament
injury show all PCLs were hypoechoic , regardless
of injury. The injured PCLs had an average
diameter of 0.88cm(range 0.54-1.21cm), while
the normal PCL had an average diameter of
0.51cm(range 0.30-0.84cm). Focal discontinuity
of the ligament is seen in complete ligamentous
tear.
PCL injury is manifested sonographically either as
enlargement of the entire ligament, appreciated
by comparison with the contralateral PCL, or by
focal disruption of the ligament.

67. MR Gradient
echo-T2 show
abnormal bright
signal and the
US show
Hypoechoic
PCL(Arrows).

68. MR Gradient echo-T2
show thickened poorly
defined PCL and the US
show Hypoechoic
PCL(Arrows) which
appears thickened .

69. MR Gradient
echo-T2 show
thickened distal
PCL with abrupt
focal cut-off
proximally and
the US show
Hypoechoic
PCL(Arrows) with
abrupt focal
changes in
caliber of the
ligament.

70. A Baker's cyst (also known as a popliteal cyst) is a fluctuant
swelling located in the popliteal space. The term is a
misnomer as the swelling is the result of synovial fluid
distending the gastrocnemius-semimembranosus bursa,
rather than being a true cyst. In older patients it is commonly
part of a chronic knee joint effusion which herniates between
the two heads of the gastrocnemius and is most commonly
secondary to degenerative or meniscal pathology.
Primary cysts have not been found to communicate directly
with the knee joint. These cysts usually occur in young people
and are symptomless.
Ultrasound scan - differentiates purely cystic masses from
more solid lesions and can exclude a DVT. It may also be
used to evaluate the cyst's internal structures, exclude
other lesions, and assess its relationship to other structures.

71. Ganglion cyst on the medial side of the knee.

72. Cyst in the retinaculum patellae.

73. Baker's cyst. Longitudinal scan of the medial aspect of the popliteal fossa
shows a well-defined cystic lesion with a narrow neck. It contains echogenic
debris and thick septa, which are characteristics of a complicated Baker cyst.

74. Baker's cyst.

75. Rheumatoid arthritis: US shows synovial thickening and effusion.
The synovial thickening appears hypoechoic or heterogenous
proliferation of the synovial membrane with poorly defined
contour.
Doppler study show increased vascularity within the
hypertrophied synovium.
Degenerative arthritis: Sonography show extent of cartilage
damage and US also show thinning or disappearance of the
cartilage.
Osteochondral defect of the femoral condyle appears as thinning
of the hyaline cartilage or as irregularities or defect of the
hyperechoic bone cortex.
Bone lesion: The cortex is an intensely hyperechoic interface with
distal acoustic shadowing. Fracture appears as breaks or steps in
the hyperechoic cortex, often accompanied by a hypoechoic
subperiosteal hematoma. Sonography has been used to measure
the thickness of the cartilaginous cap of an osteochondroma.

76. Rheumatoid arthritis. Longitudinal ultrasound scan shows a small
effusion in the suprapatellar bursa with mild irregular thickening of
the synovial membrane, which is indicative of inactive disease.

77. Degenerative arthritis. Transverse ultrasound scan of the flexed knee shows loss of
the normal hypoechoic pattern of the articular cartilage, marked irregularity of the
cartilage–soft-tissue interface, and blurring of the bone–cartilage interface.

78. Osteochondral defect. Defect and displacement are seen in the
hypoechoic articular cartilage and hyperechoic bony cortex.

79. Osteochondroma. Ultrasound scan of the knee joint shows bony
outgrowth from the upper end of the tibia. Ultrasound can be used
to measure the thickness of the hypoechoic cartilaginous cap.

80. Loose bodies. Ultrasound scan of the popliteal fossa shows two large
loose bodies within a popliteal cyst with posterior acoustic shadowing.

81. Soft-tissue masses. (A) Intramuscular ganglion: longitudinal scan along the
popliteal fossa shows a well-defined, thick-walled, multiloculated intramuscular
cyst with mild flow within the septa with color Duplex examination. (B) Soft-tissue
sarcoma: Sonogram shows a large mass in the popliteal fossa with mixed
echogenicity and increased vascularity on the color Duplex examination.

82. Pigmented Villonodular Synovitis with a vascularized hypoechoic mass
on the medial aspect of the knee extending behind the patellar tendon.

83. Soft-tissue masses: Ultrasound can differentiate cystic from solid
masses, but benign and malignant masses cannot be differentiated.
Slandered characteristic such as size, shape, location and the
echogenicity can be determined by ultrasound, Color and power
Doppler sonography allow assessment of tumour vascularity which is
helpful if malignancy is suspected. Hemangiomas have a variable
echogenicity with distal shadowing(due to the presence of
Phleboliths). Lipoma generally as hyperechogenic masses, Soft tissue
sarcomas appear as complex with increased vascularity on color and
power duplex sonography.
Muscle injury is images with sonography. Focal muscle tears and /or
hematomas may appear as simple or complex fluid collection, the age
of a hematoma influence is appearance. Rupture of the
gastrocnemius is characterized by disruption of the normal parallel
, linear echogenic and hypoechogenic appearance of the tendon at its
insertion. Fluid collection within the gastrocnemius muscle may be
seen. The hemorrhagic fluid is seen as hyperechoic at the early stages.

84. Dermatofibroma on the medial side of the knee.

85. Gastrocnemius muscle injury. Sonogram of the medial aspect of the
popliteal fossa shows disruption of the gastrocnemius muscle with a
hyperechogenic intramuscular hematoma denoting acute injury.

86. Ruptured sartorius tendon

87. Vascular lesions: Ultrasound can be used to
measure an aneurysm of the popliteal artery,
Power Doppler sonography can identify the
neck of the aneurysm and differentiate
between patent and thrombosed parts. Color
Duplex ultrasound can be used for detection
of deep venous thrombosis within the
popliteal vein, which appears distended and
non- compressible with an echogenic
thrombus, No flow detected within the vein
with color Duplex examination.

88. Partially thrombosed popliteal artery aneurysm. Color Duplex examination
of the popliteal fossa shows color signals within the patent central part of
an aneurysm, which is connected to the popliteal artery by a narrow
channel. The thrombosed part of the aneurysm shows no flow signal.

89. Deep vein thrombosis. Color Duplex examination of the popliteal fossa shows a distended
popliteal vein, a thrombus with mixed echogenicity, and no detectable blood flow.

90. Thank You.