1 General considerations topenlarge
Nonoperative treatment works well with the aid of ligamentotaxis in most humeral shaft fractures without significant initial displacement. Fractures will heal typically within three months.
Initially immobilize the arm in a splint and close to the chest to minimize pain. As pain subsides physiotherapy may be started in a functional brace.
Proximal and distal shaft fractures are not suitable for bracing. Due to the anatomy of the axilla, proximally the brace is not able to immobilize the proximal fragment. Distally, the brace may require an extension to the elbow joint with the risk of elbow stiffness.
There is a tendency for varus malalignment, particularly in obese patients. This may be countered by splint molding and arm positioning. Similarly, there is a risk of internal rotation malposition, which can be minimized by active arm use.
Healing with slight deformity does not usually cause a problem. Angulation and malrotation of 20-30° and shortening of up to 3 cm have been described as acceptable. Particularly in slender patients, this much angulation may cause visible deformity. This can be assessed during the healing process by physical examination.
2 Initial treatment top
Simple gravitational realignment of the fractured humerus is usually sufficient. With the patient upright and the limb hanging free, deformity is largely corrected by ligamentotaxis. Muscle forces may cause angulation, but, as the patient relaxes and becomes more comfortable, these forces diminish, and alignment improves. Manipulative reduction is rarely necessary.
Angulation can be improved with molding of the splint, as required.
With the patient sitting, if possible, and leaning slightly to the injured side, wrap cast padding around the upper arm from axilla to elbow. Make sure that the epicondyles of the humerus and antecubital area are well padded.
Application of splint
Apply a splint of fiberglass, or plaster, in a U-shape, with padding under the axilla. Wrap it from medial to lateral and over the shoulder (except for very distal fractures). Secure it in place with an elastic bandage that should not be too tight.
Mold this splint to be concave laterally, to correct typical varus angulation, especially in obese patients. The upper arm should appear straight when viewed from the side.
Securing injured arm
Secure the injured arm to the chest with a sling and swathe, shoulder immobilizer, or Velpeau bandage. If there is a radial nerve palsy, add a short arm splint to support the wrist in dorsiflexion.
Pitfall: Internal malrotation
In highly instable fractures (grossly displaced or comminuted) securing of the injured arm to the chest may produce an internal malrotation of the humerus since the forearm internally rotates the distal humerus, while the shoulder muscles tend to hold the humerus in neutral position. In these cases, either try to fix the arm in neutral position (ie 15° external rotation of the flexed forearm using a shoulder abduction pillow) or consider surgical fixation.
Analgesia will be required. The patient is usually more comfortable in a sitting or semireclining position, at least for the first few weeks. Motion and crepitus will be felt, and the patient should be reassured that this is normal, stimulates healing and will gradually diminish.
Caution: soft-tissue care
Occasionally, a fracture that is initially closed may become open from excessive motion or splint pressure over a prominent fracture fragment. This will require immediate change to open management with debridement and fixation.
3 Fracture brace management top
When the patient is comfortable, and the initial swelling has decreased, the temporary splint should be replaced with a prefabricated humeral fracture brace. The size should be chosen to fit the patient. Alternatively, if the services of an orthotist are available, a custom brace can be made.
This brace is a simple molded cuff that extends from axilla to elbow. Its straps can be tightened to provide containment support, but not true immobilization, for the fracture. This is only suitable for more distal fractures.
This brace extends over the shoulder and may provide somewhat better support for more proximal fractures. However, it may also prove irritating during shoulder motion.
If there is a varus tendency, the arm can be supported away from the body with a pad (“shoulder abduction pillow”) under the medial side of the elbow, as shown. This support can be quite helpful for obese patients.
Apply padded stocking, or sleeve, first to the upper arm, stabilizing the fracture as necessary with gentle distal traction.
Position the brace to avoid pressure in the antecubital fossa, or the axilla. It should be applied with correct rotation.
Initially, the patient may be more comfortable if the arm remains supported with the sling and swathe.