Fractures of the proximal humerus are common in my practice and are some of the toughest fractures to treat. There are as many different types of fractures as there are patients. This is the case of an active 75 year old female who sustained this very severely comminuted fracture of the proximal humerus (shoulder). As you can see, the head of the humerus is fractured into many pieces the a large portion of the joint surface of the head compressed downward away from the joint.






Below is the CT scan of the patient.





The above fracture is so severely comminuted (multiple fragments) with displacement of the humeral head, that it cannot be repaired without a shoulder replacement. A replacement is clearly indicated here. In a younger patient, with an intact rotator cuff, we can perform a partial shoulder replacement, preserving the bone attached to the rotator cuff and repairing it around the prosthesis.

This is a diagram of how that would be performed.

The final repair would like like th diagram below. The rotator cuff would cover the top of the prosthesis and, once the bones heal, the cuff will stabilize the joint enabling the patient to lift the arm.

The key to success here is an intact and functional rotator cuff and tuberosities that heal around the prosthesis.
Unfortunately, in some patients, the bone (greater and lesser tuberosities) will not heal, the rotator cuff may be weak or may tear resulting in extremely poor function and pain. The patient may be unable to lift the arm.

The reverse shoulder replacement does not depend on an intact rotator cuff to provide good function. If the deltoid is intact, patients can elevate the arm and have excellent pain relief and function. If necessary, the rotator cuff and tuberosities can be excised and as long as the prosthesis remain securely fixed to the bone, results are often superior to those of hemiarthroplasty. This approach can be appropriate in patients over 70 years.

I usually do not completely excise the entire cuff. I try to preserve the subscapularis and lesser tuberosity and posterior cuff and greater tuberosity. The supraspinatus is excised and the biceps is treated with tenodesis.

This patient had a massive irreparable rotator cuff tear anyway, making the reverse shoulder replacement the only acceptable option for her.



Here, you can see the retained tuberosities healing around the upper part of the prosthesis. She is doing remarkably well with minimal pain and 90 degrees of forward elevation at only 4 weeks after surgery. We are proceeding slowly with therapy to encourage the tuberosities to heal, although, if they never healed, she would still do well.


Thanks,

JTM, MD