What does FOOSH (Fall Onto An Outstretched Hand) stand for in orthopedic injury?

FOOSH: Fall Onto an Outstretched Hand in Orthopedic Injury

FOOSH stands for "Fall Onto an Outstretched Hand," which is a common mechanism of injury that frequently results in upper extremity fractures and dislocations.

Definition and Mechanism

FOOSH describes a specific traumatic event where an individual attempts to break their fall by extending their arm and landing on their open hand. This protective reflex creates a chain of force transmission that can lead to various injuries:

• The force from impact travels from the hand up through the wrist, forearm, elbow, and potentially to the shoulder
• The hyperextension of the wrist during impact is particularly problematic
• The energy of the fall is concentrated on relatively small anatomical structures

Common FOOSH-Related Injuries

Wrist Injuries

• Distal radius fractures (Colles' fracture being most common)
• Scaphoid fractures (most commonly fractured carpal bone, representing ~60% of wrist fractures) 1
• Ulnar styloid fractures (often occurring with distal radius fractures) 2
• Perilunate and lunate dislocations (serious injuries that can be easily missed) 3

Elbow Injuries

• Radial head fractures
• Coronoid process fractures
• Elbow dislocations

Shoulder Injuries

• Clavicle fractures
• Proximal humerus fractures
• Shoulder dislocations

Risk Factors for FOOSH Injuries

Anatomical variations can predispose individuals to specific injuries following a FOOSH mechanism:

• Increased radial inclination (RI > 28.6°) increases scaphoid fracture risk with odds ratio of 10.4 4
• Increased volar tilt (VT > 12.2°) increases scaphoid fracture risk 4
• Increased radial height (RH > 14.85 mm) increases scaphoid fracture risk 4
• Negative ulnar variance (ulna minus variant) increases scaphoid fracture risk 4

Diagnostic Approach for FOOSH Injuries

Clinical Assessment

1. Determine exact mechanism (height of fall, position of hand at impact)
2. Assess for point tenderness, especially over:
   • Anatomical snuffbox (scaphoid)
   • Distal radius
   • Scapholunate interval
   • Lunate

Imaging

1. Plain radiographs (first-line):

   • Standard posteroanterior and lateral views
   • Specialized views for suspected scaphoid fractures (posteroanterior in ulnar deviation, pronated oblique) 5
   • Note: Up to 30% of scaphoid fractures can be missed on initial radiographs 5

2. Advanced imaging (when radiographs are negative but clinical suspicion remains):

   • MRI (highest sensitivity for occult fractures)
   • CT (better for fracture characterization and surgical planning)
   • Bone scan (alternative when MRI unavailable)

Prevention Strategies

1. Fall prevention education
2. Proper fall techniques (learning to roll rather than brace with outstretched hands)
3. Protective equipment for high-risk activities
4. Strength training for wrist and forearm muscles

Clinical Pearls

• Always consider scaphoid fracture in patients with wrist pain after FOOSH, even with normal initial radiographs
• Non-FOOSH mechanisms can still cause typical FOOSH injuries 1
• Perilunate and lunate dislocations require emergent reduction to prevent long-term disability 3
• Consider repeat imaging in 10-14 days for suspected scaphoid fractures with negative initial radiographs 5

FOOSH injuries represent a significant portion of emergency and orthopedic visits, with proper recognition and management being essential to prevent long-term complications and disability.