Long Arm Posterior Splint

Other Names

Illustration of the plaster slab in the posterior long arm splint

Step-by-step instructions for the posterior long arm splint

Prefabricated posterior long arm splint

• Posterior Long Arm Splint
• Above Elbow Back Slab
• Long Arm Posterior Splint

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Background

• This page refers to the posterior long arm splint
• Note that it does not completely eliminate supination/pronation
  • Recommend a double sugar tong splint for fractures that require elimination

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Indications

• Supracondylar Distal Humerus Fracture
• Capitellum Fracture
• Olecranon Fractures
• Proximal Radius Fractures
• Some mid-shaft radius fractures
• Proximal ulna fractures including Coronoid Process Fracture
• Some mid-shaft ulna fractures
• Elbow Dislocation

Pediatrics

• Supracondylar Fracture
• Lateral Condyle Fracture (Peds)
• Medial Condyle Fracture (Peds)
• Olecranon Fracture (Peds)
• Radial Head Fracture (Peds)
• Medial Epicondyle Fracture (Peds)

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Contraindications

• Absolute contraindications
  • None
• Relative contraindications
  • Open fractures
  • Injuries with neurovascular compromise

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Procedure

Equipment

• See: Splinting Materials

Preparation

• Measure splint materials using unaffected arm
  • Splint extends from palmer crease up to mid-proximal humerus (about 3 inches below axilla)
  • Use 8-10 layers for the upper extremity

Technique

• See: General Splinting Technique
• Positioning
  • Elbow is flexed at 90°
  • Forearm is supinated or neutral
  • Wrist maintained in slight extension at 10 to 20°.
  • Unless needed, motion at MCP joints and thumb should be unrestricted
• Stockinette
  • Apply stockinette
  • Should extend from the proximal third of the humerus to the metacarpals.
  • Make a hole in the stockinette to allow for protrusion of the thumb
  • Smooth the stockinette to ensure there are no folds in the material.
• Cast padding
  • Wrap the padding from the MCP joint to the proximal third of the humerus slightly beyond the area to be covered by the splint material
  • Overlap each turn by half the width of the padding
  • Place cotton padding over the olecranon to prevent pressure over this bony prominence
  • Avoid excessive bulk in the antecubital fossa
• Splint application
  • Splinting material should be laid out ahead of time
  • It should be just shorter than the area covered by the padding.
  • Alternatively, if using ready-made splint material, cut a single piece to the above length.
  • Immerse the splinting material in lukewarm water.
  • Squeeze excess water from the splinting material (do not wring out plaster).
  • Apply the splint material to the posterior humerus
  • Continue past the elbow and along the ulnar surface of the forearm and finish at the metacarpals.
• Elastic wrap
  • Fold the extra stockinette and cotton padding over to cover all the edges of the splinting material.
  • Wrap the elastic wrap over the splinting material distally to proximally
  • Overlap each revolution by half the width of the elastic wrap.
  • Smooth out the splinting material using your palms rather than your fingertips
  • Maintain appropriate level of compression until splinting material hardens
• Check the distal neurovascular status
• Place the patient in a shoulder sling to support shoulder

Pearls and Pitfalls

• Alternative patient positioning
  • Appropriate only for certain stable fractures
  • This splint can be applied with the patient prone
  • The injured arm is hanging off stretcher with elbow at 90°
• Be sure to apply extra padding on the olecranon process

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Aftercare

• Try to elevate extremity for the first few days to prevent more swelling
• Advise patient to keep cast or splint clean and dry
• Do not insert objects into splint/ cast
• Monitor for complications (worsening pain, paresthesia/ numbness, color changes)
• Seek further care if unable to control pain at home

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Complications

• Plaster burn/ thermal injury
• Pressure sores
  • The epicondyles and olecranon process are particularly vulnerable.
• Nerve palsy
  • Use extra padding to protect the subaxillary area.
  • The ulnar nerve is vulnerable to compression at the posterior lateral epicondyle
  • The radial nerve is vulnerable at the anterior medial epicondyle.
• Vascular compromise
  • The axillary/brachial artery is vulnerable to compression from bone fragments, swelling, or splinting.
• Splint dermatitis
• Permanent joint stiffness

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See Also

• Procedures Main
• Splinting Main

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