A proximal humerus fracture is a common injury to the shoulder. Especially common in elderly individuals due to osteoporosis, proximal humerus fractures are among the most common broken bones in the shoulder. In fact, in patients older than 65, proximal humerus fractures are the third most common broken bone (after hip fractures and wrist fractures).
A proximal humerus fracture occurs when the ball, of the ball-and-socket shoulder joint, is broken. The fracture is actually at the top of the arm bone (the humerus). Most proximal humerus fractures are non-displaced (not out of position), but about 15-20% of these fractures are displaced, and these may require more invasive treatment.
The most significant problem with proximal humerus fractures are the treatment is very limiting, and the outcomes are often fair or poor. Many patients who sustain this injury do not regain full strength or mobility of the shoulder, even with proper treatment.
Displaced Proximal Humerus Fractures
When the bone is not in proper alignment, the fracture is called displaced. In proximal humerus fractures, the severity is often described by how may of the major parts of the proximal humerus fracture are displaced. There are four "parts" of the proximal humerus, so a displaced fracture can either be 2-part, 3-part, or 4-part (a non-displaced fracture is, by definition, 1-part). In general, the more displaced parts, the worse the prognosis.
The parts of the proximal humerus are called the tuberosities (the greater and lesser tuberosity), the humeral head (the ball of the shoulder), and the humeral shaft. The tuberosities are next to the ball, and are the attachments of the important rotator cuff muscles. For a part to be considered displaced, it either has to be separated from it's normal position by more than a centimeter or rotated more than 45 degrees.
Treatment of Proximal Humerus Fractures
About 80% of proximal humerus fractures are non-displaced (not out of position), and these can almost always be treated in a sling. Typical treatment is to rest the shoulder in the sling for 2-3 weeks, and then begin some gentle range-of-motion exercises. As healing progresses, more aggressive shoulder strengthening exercises can resume, and full healing typically takes about 3 months.
In more severe injuries where the bone is displaced (out of position), it may be necessary to realign or replace the damaged bone. Determining the best treatment depends on many factors including:
- Age of the patient
- Hand dominance
- Activity level of the patient
- Degree of displacement of the fracture
The options for surgery include realigning the bone fragments and holding them in position with metal implants, or a shoulder replacement procedure is performed. If the fragments of bone can be fixed, either pins, screws, wires, large sutures, or a plate will be used to hold the bones in place.
If there are concerns about repairing the bone, it may be decided to perform some type of shoulder replacement. If a replacement procedure is recommended, options include a standard shoulder replacement, a hemiarthroplasty, or a reverse shoulder replacement.
Nho SJ, et al. "Innovations in the Management of Displaced Proximal Humerus Fractures" J Am Acad Orthop Surg January 2007 vol. 15 no. 1 12-26