Humerus - Upper arm

General

The humerus is the bone in your upper arm between your shoulder and the elbow.

 When referring to a humeral fracture doctors are often talking about the middle section or the shaft.

 If the break is near or involves the ball part of the shoulder it is called a Proximal humeral fracture. 

 If it involves the end of the bone near the elbow it may be called a supracondylar fracture or distal humerus fracture.

 It is important to differentiate where it is broken as it affects treatment.

 The rest of this page assumes it is in the shaft or the middle section.

Diagnosis

The diagnosis is usually pretty straightforward, with pain and movement of the bones in the middle of the arm.

 It may follow a twisting injury to arm, eg. while arm wrestling, or a fall on the arm.

 X rays confirm the diagnosis and demonstrate exactly where the break is in the bone.

 It is important to identify if any nerve has been injured.

 The radial nerve is the most commonly injured nerve in humeral shaft fractures. The radial nerve is tested by checking you have normal sense of

feeling at the base of your thumb and whether you can fully extend (straighten) your wrist and fingers.

Treatment

 Treatment depends on the presence or absence of any other injuries.

 90 - 95% of isolated uncomplicated humeral shaft fractures will heal with non-operative treatment.

 If the patient has several other injuries or injuries on both arms then surgery might be considered.

 If the fracture is open, ie. has an overlying wound then often surgery is needed.

 If there is an associated radial nerve injury then treatment depends on how severe this injury is to the nerve.

Non operative treatment

 Non operative treatment involves a humeral brace.

 A humeral brace fits like a sleeve around the upper arm, and has adjustable straps.

 It is important to remember when waiting for your humeral shaft fracture to heal, that a little bit of movement is good, too much movement is bad.

 Doing too much can be just as bad as doing too little.

 It is not uncommon for patients to feel the fracture fragments moving and clicking for the first few weeks. This is normal and nothing to be

concerned about.

 It is important to do your exercises regularly throughout the day.

 It is important to regularly adjust/ tighten the velcro straps so the brace fits snugly on your upper arm, supporting the fracture.

 Within the first couple of weeks you should strive to get your elbow/ arm straight.

 With your arm hanging down by your side straight you are safe as gravity pulls the fractured fragments into correct alignment.

 Once you can hang your arm by your side straight, tighten the brace and initially assisting it with the other arm actively flex the elbow bringing your

hand to your mouth.

 Lean forward with your arm hanging down and gently roll swing it in circles to help prevent shoulder stiffness (pendulum exercises).

 It is important the brace is snug and firm when you do your exercises.

 As the days and week go by and the fracture gets stiffer and stiffer you can increase the exercises.

 Frequent regular exercises throughout the day is better than pushing it first thing in the morning.

 AVOID Abducting the arm till the fracture has healed, ie don't take your arm out to the side.

 Work in straight lines with your arm hanging at your side.

 Listen to your arm, a little ache is fine, if it really hurts and aches that night through to the next day, then you are doing too much.

 That does not mean stop, just come down a little on your exercises.

 Once comfortable with your arm hanging down by your side you can remove the brace to get some air to your arm and allow for cleaning.

 It is possible to get material braces with reinforcing metal rods, they can be worn to bath, shower or swim in.

 The average duration of wearing a humeral brace is 12 weeks.

Operative treatment

 Most humeral shaft fractures are treated without an operation as above in a humeral brace.

There are several ways to fix a humeral shaft fracture, the most common being plate and screws or an intramedullary

nail.

 As with any operation there are pro's and cons to have an operation and pro's and cons as to the way of fixing the

fracture, plate vs nail.

 The main risks of surgery are infection and nerve injury.

 The radial nerve winds round the humerus and can be damaged while placing the plate or stretched when inserting

an intramedullary nail.

 The radial nerve supplies motor power to the wrist and injury leads to the inability to extend or straighten up the

wrist.

 Occasionally surgery is needed if the fracture does not heal with non operative treatment, ie. develops a non union.

 If this is the case it is better to treat it with a plate and screws rather than an intramedullary nail.

Outcome

Most humeral shaft fractures will heal with non operative treatment and lead to good arm function.

If the fracture does not heal then surgery is possible to help it heal.

 If the radial nerve has been injured, most will recover spontaneously, and if no sign of recovery it is possible to repair the nerve.

 If the nerve does not recover, further treatment is possible, this involves the transfer of tendon.