Throwing injuries to the elbow

The position of throwing starting with the arm overhead behind you followed by the follow through

and release generates large forces across the elbow and shoulder.

All the kinetic energy stored in the lower limbs, pelvis and thorax is then transferred down the arm

across the shoulder and elbow joints.

 After the ball is released the body then needs to decelerate the arm and bring it back.

As the energy is funnelled along increasingly smaller motion segments the forces across these

segments multiply.

 Professional pitchers can generate up to 92 Nm of humeral rotation torque; this is enough force to

break the upper arm of someone not conditioned to these forces.

In semi professional and professional throwers with time the persistent valgus stress (away from the midline) leads to changes in elbow

anatomy.

The ligaments on the inner side (medial side) of the elbow called the Medial collateral ligaments or Ulna collateral ligaments stretch out.

The medial collateral ligaments (MCL) help guide the elbow parts as the elbow straightens.

If they have stretched out a part of the elbow (olecranon) no longer enters the olecranon fossa smoothly and impinges on the humerus.

This injures the cartilage and bone on the posteromedial (back and inner side) aspect of the olecranon.

This complex of laxity of the MCL and the posteromedial impingement lesion is often referred to as hyperextension valgus overload.

Treatment

Non operative

Prevention is important avoid overuse particularly in the young thrower who's bones and joints are still developing.

Most of the advice on throwing has been written in the baseball literature from the USA.

American sports medicine institute

See guidelines on pitching 2006 (pdf file click here) or visit the web site  www.asmi.org.

Once an injury or pain occurs it is important to rest the arm.

Guidance for professional pitchers is to have 3 months a year where no pitching or sport is undertaken that generates a valgus stress across

the elbow.

Control inflammation pain and swelling with RICE

•

 R-rest

•

I-ice

•

C-compression

•

E-elevation

Non steroidal anti inflammatory (NSAID's) will help reduce inflammation and pain.

This should be followed by a structured rehabilitation program that includes paying particular attention to your throwing technique.

For example in baseball pitchers the less experienced pitcher will open the torso to the front before the front foot is placed on the ground.

This "early opening" places more torsional and valgus stresses on the elbow.

Improve the strength and endurance of the flexor pronator muscle mass particularly, Flexor carpi ulnaris as they are secondary stabilizers of

the elbow and will reduce the strain on the MCL.

 Operative

For acute ruptures of the MCL in highly competitive athletes and in chronic injuries that do not respond to a rehabilitation program of 3-6

months it is possible to repair or reinforce the MCL.

 This is an open procedure and may require a tendon graft to reinforce the tendon.

It is possible to arthroscopically (keyhole surgery) to excise the impingement lesion including debriding the hypertrophied synovium (joint

lining), where the olecranon impinges on the humerus.

However if repeated valgus stresses continue this may worsen the MCL instability.

References

Orr Limpisvasti, Neal S. ElAttrache, and Frank W. Jobe; Understanding Shoulder and Elbow Injuries in Baseball; J. Am. Acad. Ortho. Surg.,

March 2007; 15: 139 - 147.