Neurologic and Musculoskeletal Imaging Studies

Skeletal Traumaواحدی هوشنگ دکترامیر

توانبخشی و فیزیکی متخصصطب

7قسمت

An avulsion fracture is an injury to the bone in a place where a tendon or ligament attaches to the bone. When an avulsion fracture occurs, the tendon or ligament pulls off a piece of the bone.

avulsion fracture

Avulsion fractures can occur anywhere in the body, but they are more common in some areas. For example, we commonly see avulsion fractures around the pelvis.

Avulsion fractures are also more common in children than adults

1. medial epicondyle distal humerus________ flexor pronator muscle

2. volar aspect of phalanges_________ flexor tendon 3. dorsal aspect of phalanges_________ extensor

tendon4. Inferior patella ____________ patella ligament5. Superior patella______ ______ quadriceps6. Posterior calcaneus__________ achilles tendon7. Olecranon process___________ triceps8. Tibial tuberosity____________ patella ligament

9.anteroinferior iliac spine _______ straight head of rectus femoris

10. Anterosuperior iliac spine _______sartorius and tensor fasciae latae,

11.lesser trochanter ___________ iliopsoas 12.ischial tuberosity ___________hamstrings and

part of adductor magnus 13.greater trochanter ___________ gluteal muscles 14.iliac crest_____________ insertion of abdominal

tensor fasciae latae, gluteus medius, latissimi dorsi, gluteus maximus

Avulsion Fracture of Lesser Trochanter of Femur

avulsion fracture of the anterior superior iliac spine (arrows)

Rectus Femoris Avulsion. (arrow), which is characteristic for an avulsion of the rectus femoris muscle from the anterior inferior iliac spine.

Avulsion Off the Ischium. (arrow) . These findings are characteristic for an ischial avulsion

 Avulsion injury. Florid new bone formation (arrow) following an avulsion injury of the reflected head of the rectus femoris muscle in a young footballer.

Figure 18. Avulsion fracture.Avulsion fracture. crescentic adductor avulsion fracture (arrow).

Avulsion fracture Posterior calcaneus achilles tendon

Mallet Finger (baseball finger ). A small avulsion injury is noted at the base of the distal phalanx, which is where the extensor digitorum tendon inserts.

Avulsion fracture elbow

Olecranon avulsion fracture. patient with osteogenesis imperfecta who has had bilateral recurrent fractures in the same region. The avulsed fracture fragment is proximally retracted by the triceps muscle.

Medial epicondyle avulsion fracture with entrapment in an older patient. the entraped medial epicondyle is distal to the trochlea and is absent from its normal position.

Gamekeeper’s Thumb. A small avulsion injury on the ulnar aspect of the first metacarpophalangeal joint (arrow) . This is the insertion site for the ulnar collateral ligament and usually requires internal fixation

Triquetral fracture. There is a small avulsion from the dorsum of the triquetrum seen only on the lateral projection (red arrow). The pisiform overlies the triquetrum in the AP and oblique views and tends to obscure the fracture (white arrows).

Most Commonly Missed Fractures

1. Scaphoid

2. Elbow (Radial Head)

3. Calcaneus

Normal development anatomy of the hand during childhood. A 2-year-old boy (A), 5-year-old boy (B), 7-year-old boy (C), and 15-year-old boy (D).

Thin cortical breaks in the distal head and waist

Step-Off break in waist or proximal scaphoid angulation

Scaphoid Fracture: Keep In Mind

1. Get dedicated scaphoid views if clinical suspicion is high. Re-image if necessary

2. Even with proper imaging, not all scaphoid fractures will be visible on plain film. Obtain further imaging and orthopedic consult if occult fracture is suspected

Normal variation and development of the elbow in children. A, medial epicondyle is visualized, but the lateral is not. This asymmetrical development from one side to the other can occur normally. Because lateral epicondyle fractures are rare, you should suspect that this is an apophysis.

Normal lines. shows the 2 lines used for radiographic analysis in patients with elbow trauma. The solid anterior humeral line is drawn along the anterior cortex of the distal humeral metaphysis and should pass through the middle third of the capitellum. Passage of the anterior humeral line either anterior to the capitellum or through the anterior third of the capitellum demonstrates that the capitellum is positioned too far posteriorly; this finding indicates a distal humeral fracture. Failure of the radiocapitellar line to pass through the capitellum indicates radiocapitellar dislocation.

Typical supracondylar fracture Lateral view demonstrates an abnormal relation of the capitellum to the anterior humeral line, which passes along the anterior margin of the capitellum. C) which shows the anterior humeral line passing normally through the middle third of the capitellum.

Typical supracondylar fracture Note the abnormal relation of anterior humeral line and the lateral view.

Radiographic Signs of Radial Head Fracture on Lateral Elbow Exam

Can you find the fracture now?

1. Ask for 3 Views: AP, oblique, lateral2. Look for sail sign and posterior fat pad3. If these signs are present but no fracture is

identified, radial head fracture is likely4. Additionally, look for a fracture line, and contour

deformity

Elbow Fracture: Keep in Mind

Boehler's angle is defined as the angle formed by two lines: one drawn tangent to the superior aspect of the calcaneus and the second drawn tangent to the inferior aspect of the calcaneus. The angle normally ranges from 20 to 40 degrees.

Reduced Böhler’s Angle Fracture

Vertical Sclerosis in Calcaneal Stress Fracture

Anterior Process Avulsion

Vertical Sclerosis in Calcaneal Stress Fracture

Anterior Process Avulsion

Calcaneal Fracture: Keep In Mind

1. Böhler’sAngle 20°-40°2. Look for fracture: follow all lucent lines carefully3. Consider associated injury (and think about the other foot!)4. Stress Fracture: Heel pain and vertical sclerosis5. Check for Anterior Process Avulsion in patients with chronic ankle/foot pain and

inversion injury –CT or MRI may be required to make the diagnosis