Posterolateral Approach to the Elbow indications:
Posterolateral Approach to the Elbow (also known as Kocher approach) is used for:
- Management of pathologies of the radial head:
- Open reduction and internal fixation of the radial head.
- Radial head replacement.
- Radial head excision.
- Lateral collateral ligament (LCL) reconstruction or repair.
- Management of coronoid fractures (limited access).
Position of the Patient
- Supine position:
- With the upper extremity supported on a hand table or on patient’s trunk.
- Lateral decubitus:
- With the arm supported over a bolster.
- Forearm is pronated in both positions.
Landmarks and Incision
- Lateral humeral epicondyle.
- Radial head:
- 2.5 cm distal to lateral epicondyle, head (or crepitus in fractured) is palpable with pronation/supination.
- Make a 5cm longitudinal or gently curved incision based off the lateral epicondyle and extending distally over the radial head approximately.
- Incision angle can be varied based on need to address associated pathology.
The Internervous plane of Posterolateral Approach to the elbow (Kocher approach) lies between:
- Aanconeus muscle: it’s innervated by the radial nerve.
- Extensor carpi ulnaris muscle (ECU): it’s innervated by the posterior interosseous nerve.
- Incise deep fascia in line with incision.
- Identify plane between Extensor carpi ulnaris muscle (ECU) and anconeus muscle distally.
- Maintain arm in pronation to move posterior interosseous nerve away from field of operation.
- Split proximal fibers of supinator muscle, staying on the posterior cortex of the radius away from posterior interosseous nerve.
- If Lateral collateral ligament is intact, stay 1 cm anterior to crista supinator to avoid damage.
- In cases of elbow dislocation, Lateral collateral ligament frequently is not intact.
- Incise capsule longitudinally:
- Avoid dissecting distally or anteriorly (risk of posterior interosseous nerve injury).
- Maintain dissection in mid radiocapitallar plane to avoid damaging the Lateral collateral ligament.
- Proximal Extension:
- Extend superficial dissection by dissecting down onto lateral supracondylar ridge.
- Avoid origin of Lateral collateral ligament unless operation directed at its repair/reconstruction.
- Distal Extension:
- Posterolateral Approach to the Elbow ( Kocher approach ) should not be extended distally as this places the posterior interosseous nerve at risk.
Structures at risk during Posterolateral Approach to the Elbow (Kocher approach) include:
- Posterior Interosseous nerve:
- It’s not in danger as long as dissection remains proximal to annular ligament.
- Release supinator along posterior radius border beyond annular ligament with forearm in full pronation.
- Retractors placed blindly anteromedially or with excessive retraction may lead to nerve injury.
- Radial nerve:
- It’s not in danger as long as elbow joint is entered laterally and not anteriorly.
- Surgical Exposures in Orthopaedics book – 4th Edition
- Campbel’s Operative Orthopaedics book 12th