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MRI of the Hips and
Pelvis
Hips and Pelvis
Protocols
Vascular abnormalities
Fractures
Soft tissues
Labrum and FAI
Hips and Pelvis
Protocols
Vascular abnormalities
Fractures
Soft tissues
Labrum and FAI
Hips and PelvisProtocol
Coil - TORSOPA, Body Plane - coronal, axial FOV - 24-30 cm (iliac crest to
lesser troch) Slice thickness 6-7mm/3mm T1 and T2WI
LabrumProtocol
Coil - flexible wrap Plane - axial, coronal• FOV - 14-24 cm
(supraacetab to l. troch) Slice thickness - 3/.3 mm T1 and T2WI (+ contrast)
Hips and Pelvis
Protocols
Vascular abnormalities
Fractures
Soft tissues
Labrum and FAI
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Vascular abnormalities
Avascular necrosis (AVN)
Idiopathic Transient Osteoporosis of Hip (ITOH)/TPBME
AVN
MR findings
Diffuse edema (early) ??Serpiginous line of low SI (between
10-2 o’clock on axials)Collapse, joint space narrowingVolume of head involved (axial plane)
25 y.o. known AVN left hip AVNWhat the surgeon wants to know
• Volume of head involved (axial)• Evidence of degenerative dz• Presence of collapse
AVN
TreatmentEarly diagnosis:
joint-sparing techniques -core decompression, rotational osteotomy, FVFG
Idiopathic transient osteoporosis of the hip (ITOH)
Uncommon, painful, self-limited
Uncertain etiology, likely vascular No trauma
Young adults, M > F (left)
Can migrate to other joints
Resolves spontaneously
Korompilias, et al. SKEL RAD 2009; 38: 425-436
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ITOH
MR findings
• signal femoral head to intertrochanteric region
• Joint effusion
DDX: septic hip, AVN,stress fx
45 y.o. male with left hip pain
ITOH
Treatment
Protective weight-bearing
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Hips and Pelvis
Protocols
Vascular abnormalities
Fractures
Soft tissues
Labrum and FAI
Fractures
Stress/Fatigue
Occult traumatic
Insufficiency
Stress fractures
Femoral neck- compressive, tensile
Pubic rami
Sacrum
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College freshman w/ groin pain
Axial T 1 and T 2 w/FS
42 y.o. ultra marathoner
22 y.o. collegiate tennis player
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20 y.o with left SI joint pain
MR strongly indicated for negative plain film
Recommend exam by ortho
Include sacrum in FOV
Occult traumatic fractures Occult traumatic fractures
Kirby, et al AJR 2010; 194: 1054-1060
• 92 pts ER hip films (avg age 71yrs) films read as wnl or ?? for fx
• 6 hip fx
• 17 pelvic fx
Khurana, et al AJR 2012; 198: 581-588
• fractures – 162 (42%)
• hip fx – 39 (10%)
• pelvic fx – 68 (17%)
• AVN – 33 (9%)
Abbreviated MRI for patients presenting toED with hip pain
Coronal STIR & T1
Sens & spec = 99%
N = 385
Occult traumatic fractures
Fracture demonstration within 24 hrs
Specific--fracture line
Cost effectiveDeutsch et al.Radiology 170:113 1989Verbeeten et al. Eur Radiol 15: 165 2005
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Craig JG, et al. Skel Radiol 2000:29(10): 572-576Feldman F. AJR 2004:183:323-329
84 y.o. female with Right hip pain No h/o trauma
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Insufficiency fractures
Bone weakened by osteoporosis/radiation
May be radiographically occult
Multiple fractures can co-exist
Subcapital, intertrochanteric, sacral, supraacetabular, pubic bones
80 y.o. with severelow back pain
Supraacetabular
Curvilinear (“eyebrow-shaped”) low signal
Parallels roof acetabulum
Insufficiency fractures
SUPRA-ACETABULARINSUFFICIENCYFRACTURE
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Hips and Pelvis
Protocols
Vascular abnormalities
Fractures
Soft tissues
Labrum and FAI
Sports herniaSports hernia
Imbalance btw rectus abd and adductor muscles
Symphyseal instability
Pain can be in symphysis, hip or back
aka pubalgia, osteitis pubis
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Athletes, older pts
Systemic disease Biceps femoris, semitendinosus,
semimembranosus
Avulsion fracture, partial tear,tendinopathy
Hamstring injuries
Hamstring injuriesHamstring injuries Hamstring injuriesHamstring injuries
Greater trochanteric bursitis
Pain lateral aspect of hip
Usually due to repetitive hip flexion
Mimics gluteus min/medius tendon tears(often associated)
Rx anti-inflammatories/steroid injection
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Hips and Pelvis
Protocols
Vascular abnormalities
Fractures
Soft tissues
Labrum and FAI
Labrum
Rim of fibrocartilaginous tissue around acetabulum
Low signal, triangular structures (axial and coronal)
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HIP PLICA
Bencardino, et al; Skel Rad 2011; 40: 415-421
• Labral - 76%
• Neck – 97%
• Ligamental – 78%
Labral tears
• Persistent pain, clicking ROM
• Single traumatic event, chronic stress, DDH
• CMR - 8% SEN. LARGE FOV
• CMR - 25% SEN. SMALL FOV
• MRa - 92% SEN. SMALL FOV p < .05
Labrum
Toomayan GA, et al. AJR (2006):186; p.449
N=30
Labral tearsAppearance - seen best with surface coil and
MRA
• Linear, diffuse high signal
• Deformity of contour
Detachment from acetabulum
Paraarticular cyst
Labral tears
• Most tears anterior-superior labrum
• Posterior and posterosuperior tears more common in younger individuals
• Chondral defects associated 30% of labral tears and detachments
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Iliopsoas tendon crosses over labrum
Acetabular cartilage extends medially
Sublabral recess
Mimickers
Labral tears
• 57 pts• 10 (18%) recesses
44 (77%) tears• Recess: linear contrast,
partial separation, no peri-labral abn
• Most recesses in ant-inf labrum
Studler, et al. Rad 2008; 249: 947-954
Sublabral recess
12
9
Ant
Sup
7/0
2/2
1/22
0/20
(recess/tear)
27 y.o tennis player with right hip pain
30 y.o. professional golfer
22 y.o. female w/ 2 “normal” CMR
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T2
T1
60 y.o with acute hip pain
Femoroacetabular impingement
Abnormal configuration of acetabulum
“Pincer” type Bony protuberance of femoral neck
(abnormal femoral head/neck junction)
“Cam” type Synovial herniation pit
Kassarjian et al, Rad.236(2)p.588-592.
ALPHA ANGLE
Kassarjian A et al. Radiology 2005;236:588-592
• Not reliably reproduced
• Not necessary to obtain
19 year old basketball playerLeft hip pain/severe limited IR
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Confirmation Arthro Study 1 month later
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34 y.o. male with left hip pain
Impingement
Acetabular cartilagedefect w/ loose body
40 y.o female with hip pain after yoga
Dietrich, et al. Radiology 2012; 263: 484
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Conclusions
Hip MRI increasingly relied on by surgeons
Hip pain and negative x-rays = MRI
Measurements for FAI not needed
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