Fracture of the Greater Tuberosity (GT)
Fractures of the Greater Tuberosity are unique because they are essentially Rotator Cuff injuries. The Supraspinatus, Infraspinatus, and Teres Minor muscles attach here. Displacement can lead to severe impingement.
[Image of Greater Tuberosity Fracture Anatomy]1. Mechanism of Injury
- Avulsion: Violent contraction of the muscles (e.g., during anterior dislocation) rips the bone off.
- Direct Blow: Fall onto the shoulder.
2. Clinical Importance
Why is displacement critical?
Even small displacement (> 5mm) superiorly can block abduction by hitting the acromion (Mechanical Block). Displacement posteriorly prevents external rotation.
Even small displacement (> 5mm) superiorly can block abduction by hitting the acromion (Mechanical Block). Displacement posteriorly prevents external rotation.
3. Management
- Minimally Displaced (< 5mm): Conservative. Sling immobilization.
- Displaced (> 5mm): Surgery is mandatory.
- Screw Fixation: For large fragments.
- Suture Anchors/TEB: For comminuted fragments (treated like a cuff repair).
4. Physiotherapy Notes
- Caution: Active abduction is delayed (6 weeks) to prevent the deltoid from pulling the fragment away.
- Stiffness: Very common due to proximity to the joint capsule.
25 Practice MCQs
Q1. Which muscles attach to the Greater Tuberosity?
Answer: A). The posterior and superior cuff muscles.
Q2. What attaches to the Lesser Tuberosity?
Answer: A). The only anterior cuff muscle.
Q3. GT fractures are most commonly associated with:
Answer: A). Occurs in roughly 15-30% of anterior dislocations.
Q4. The threshold for surgical fixation of superior displacement is usually:
Answer: A). >5mm causes subacromial impingement.
Q5. An isolated GT fracture is often treated similar to:
Answer: A). Because the cuff attaches to the bone fragment.
Q6. Malunion of the GT superiorly leads to:
Answer: B). The bone hits the acromion arch during elevation.
Q7. Conservative treatment involves immobilization for:
Answer: B). To allow bony healing before active cuff use.
Q8. Which movement is most restricted/painful in GT fractures?
Answer: A). These are the actions of the attached muscles.
Q9. The "suture bridge" technique is used for:
Answer: A). Compresses the fragment without bulky screws.
Q10. Occult (hidden) GT fractures are best seen on:
Answer: B). X-rays often miss non-displaced fractures.
Q11. Early passive external rotation is limited to how many degrees in rehab?
Answer: A). Excessive ER pulls on the GT fragment.
Q12. The Axillary nerve runs:
Answer: A). Can be injured during surgery or dislocation.
Q13. In a 2-part GT fracture, the shaft and head are:
Answer: A). Only the GT is broken off.
Q14. Large displaced GT fragments are best fixed with:
Answer: A). Provides strong compression.
Q15. Is deltoid strengthening safe immediately?
Answer: B). Active deltoid contraction can displace the fragment via shear forces.
Q16. A "Seatbelt Injury" to the shoulder often causes:
Answer: C). Clavicle is more common, but GT can occur with direct impact.
Q17. Non-union of GT is:
Answer: B). Malunion is much more common than non-union.
Q18. Posterior displacement of GT blocks:
Answer: B). Mechanical block against the posterior glenoid.
Q19. Arthroscopic assistance is mainly used for:
Answer: A). Ideal to check for associated labral/cuff tears.
Q20. The most common complication after surgery is:
Answer: B). Aggressive rehab is needed once stable.
Q21. Can GT fractures occur with Inferior Dislocation?
Answer: A). Possible with any high-energy dislocation.
Q22. Smoking affects healing by:
Answer: A). Increases risk of non-union/cuff failure.
Q23. Strengthening typically begins at:
Answer: C). Bone must be healed first.
Q24. Teres Minor attaches to:
Answer: A). Supraspinatus is Superior, Infraspinatus is Middle.
Q25. "Snow cap" sign on X-ray refers to:
Answer: B). Sclerosis of the humeral head (unrelated to GT fracture but good to know).
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