| Internervous plane |
- None
- the extensor mechanism is either split or detached
- the radial nerve innervates the triceps muscle more proximally
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| Preparation |
- Anesthesia
- general
- supraclavicular or infraclaviclar nerve block
- Position
- prone or lateral decubitus
- with elbow flexed and arm hanging from side of table
- Tourniquet
- can be applied if needed as sterile tourniquet to upper arm
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| Approach |
- Incision
- begin 5cm proximal to the olecranon in the midline of the posterior distal humerus
- curve laterally proximal to the tip of the of the olecranon along the lateral aspect of the olecranon process
- then curve medially over the middle of the posterior aspect of the subcutaneous ulna
- Superficial dissection
- first, palpate the ulnar nerve and fully dissect it out
- is helpful to pass tape or penrose for identification at all times
- incise deep posterior fascia in the midline
- can either split triceps fascia, or continue with olecranon osteotomy
- if performing olecranon osteotomy, drill and tap olecranon prior to osteotomy
- score the olecranon with an osteotome to allow perfect reduction when the osteotomy is repaired
- V-shaped osteotomy of the olecranon 2 cm from the tip using an oscillating saw
- Deep dissection
- strip soft tissue from the edges of the osteotomy site and retract the olecranon fragment proximally
- subperiosteal dissection of the medial and lateral borders of the humerus allows exposure of entire distal fourth of the humerus
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| Dangers |
- Ulnar nerve
- should initially be indentified and protected during the approach
- can usually be palpated 2cm proximal to medial epicondyle
- Median nerve
- strict subperiosteal dissection off the anterior surface of the humerus protects the nerve
- flexion of the elbow relaxes the anterior structures.
- Radial nerve
- in danger proximally as it travels from the posterior to anterior brachial compartments through lateral intermuscular septum
- can usually be found at the lateral border of the humerus near distal 1/3 junction
- Brachial artery
- runs with the median nerve (see above)
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