III. Preparation: Ultrasound
- Low frequency (5 MHz) curved array probe
- Depth: Start at 9-10 cm
IV. Technique: Anterior Hip in Long Axis (LAX) and Hip Arthrocentesis
- Indications- Differentiates hip effusion (intracapsular) from Iliopsoas Bursitis (extracapsular)
- Best image to guide Hip Injection or aspiration (broad femoral neck as target)
 
- Positioning- Patient supine with hip in neutral position (hip exposed to inguinal ligament)- Internal rotation of hip and knee flexion may aid visualization of small hip effusions
- Slight external rotation may help to visualize other structures
 
- Ultrasound linear probe in line with femoral neck (perpendicular to mid-inguinal ligament)- Palpate femoral artery and probe is placed lateral to this position
 
- Ultrasound probe indicator toward Umbilicus
 
- Patient supine with hip in neutral position (hip exposed to inguinal ligament)
- Images
- Components- Iliopsoas Muscle (overlying hip)- Overlies all deeper structures
 
- Acetabulum of hip (screen left)- Bright, hyperechoic
 
- Femur with overlying capsule- Extra-capsular space (Iliopsoas bursa)
- Joint capsule- Linear band follows femoral head and concave over femoral neck
- Hyperechoic due to contained iliofemoral and pubofemoral ligaments
 
- Intracapsular space- Increasing depth (and convex expansion of the space) suggests Hip Joint effusion
- Normal depth: 5 mm or within 1-2 mm of intracapsular space depth of opposite hip
- Abnormal depth >8-9 mm
 
- Bone- Femoral head- Rounded, convex
 
- Femoral neck
 
- Femoral head
 
 
- Iliopsoas Muscle (overlying hip)
- 
                          Arthrocentesis
                          - Prepare skin- Mark landmarks (but also performed under Ultrasound guidance)
- Antiseptic (e.g. Chlorhexidine)
- Local Skin Anesthesia (and along intended track) with Lidocaine 1% with Epinephrine
 
- Aspirate joint- Spinal needle (3.5 inch, 20 gauge) advanced under Ultrasound guidance toward fluid pocket
 
 
- Prepare skin
V. Technique: Anterior Hip in Transverse or Short Axis (SAX)
- Indications- Confirms hip effusion (intracapsular)
 
- Positioning- Patient supine with hip in neutral position or slight external rotation (hip exposed to inguinal ligament)
- Probe in short axis with approximately 20 degrees angulation (probe indicator toward iliac crest)- Probe rotated 90 degrees from the long axis view used above
 
 
- Images
- Components: Superficial
- Components: Deep to Iliopsoas Muscle- Joint capsule
- Intracapsular space
- Femoral head
 
VI. Technique: Lateral Hip at Trochanteric Bursa
- Indications- Evaluates Trochanteric Bursitis (Gluteus Medius bursa)
- Directs trochanteric bursa region injection (typically tendonosis rather than the actually rare Bursitis)
 
- Positioning- Patient lies on their side (decubitus)
 
- View 1: Long Axis (LAX)- Positioning- Ultrasound probe in long axis overlying greater trochanter
- Ultrasound beam tilted slightly anteriorly- Better demonstrates IT Band interface
- Gluteus minimus attachment at anterior facet
 
- Ultrasound beam tilted slightly anteriorly- Gluteus medius attachment at lateral facet
 
 
- Components- Gluteus Maximus and Iliotibial Band (superficial)
- Joint capsule
- Femoral Greater Trochanter
 
 
- Positioning
- View 2: Short Axis (SAX, transverse)- Positioning- Ultrasound probe in short axis overlying greater trochanter (probe turned 90 degrees from above)
 
- Images
- Components: Deep- Anterior facet of Greater trochanter- Appears similar to the front facing side of half dome (Yosemite)
- Gluteus minimus attaches at anterior facet
 
- Lateral facet of Greater trochanter- Appears similar to the back side of half dome (Yosemite)
- Gluteus medius attaches at lateral facet
 
 
- Anterior facet of Greater trochanter
 
- Positioning
VII. Technique: Posterior Hip at Piriformis Muscle
- Indications- Piriformis injection in Sciatica (or Piriformis Syndrome)
 
- Positioning- Patient supine
- Ultrasound probe
 
- Images
- Components- Gluteus maximus Muscle- Superficial, hypoechoic, large
 
- Piriformis Muscle- Deeper, more hyperechoic, small
- Tapers laterally and inserts on greater trochanter
- Identify piriformis Muscle dynamically by rotating foot internally and externally while Ultrasounding
 
- Sciatic nerve- Immediately deep to piriformis Muscle
 
 
- Gluteus maximus Muscle
VIII. References
- Moore (2010) Hip and Spine Ultrasound Video, GCUS
- Moore (2016) Musculoskeletal Ultrasound Course, Gulf Coast Ultrasound, St. Pete's Beach, FL
