If you're anything like me, you were a little confused by all of the medical terminology being thrown around this week regarding Roy Halladay and his shoulder injury. Thankfully, Dr. Bradford Parsons, Assistant Professor at New York's Mount Sinai Hospital in the Leni and Peter W. May Department of Orthopaedics, volunteered to answer some of our questions.
1. What is the latissimus dorsi muscle, where is it located, and what functions does it perform?
The latissimus is a posterior shoulder and upper back muscle that goes from the trunk/shoulder blade to the humerus (arm bone) and help maneuver the arm into the body (adduction) and internal rotate the arm around the shoulder joint.
2. Is this a common injury for athletes (particularly pitchers), and what is the standard course of treatment?
Given that the latissimus is a muscle which spans the shoulder joint and scapular area, it is susceptible to injury with throwing but is not a common cause of shoulder pain in throwers.
3. How is the injury usually diagnosed?
Latissimus strains, like any muscle strain are diagnosed based on the patients history: complaints or symptoms, activities that bring on pain (in this case which part of the throwing motion does the patient feel pain), and exacerbating events; as well as their physical examination: tenderness in the muscle, pain with resisted muscle strength testing or muscle stretch testing, etc; and also by imaging such as an MRI which may show inflammation in the muscle or tendon itself.
4. What is the difference between a Grade 1 and Grade 2 strain of the latissimus, and how does that affect the recovery timetable?
Grading of muscle strains has to do with the severity of the injury: the amount of muscle inflamed or damaged. A grade 2 strain is a more substantial injury and may take longer to recover.
5. The Phillies have given a 6-to-8 week timetable for Halladay's return to game action. Given what you know about the extent of the injury, does that seem appropriate, or somewhere on the optimistic or pessimistic side?
As I have not examined nor have first hand knowledge of Mr. Halladay's injury it is hard to say, but a 6-8 week recovery for a muscle strain such as the latissimus is a reasonable estimate.
6. Would "pitching through" an injury like this exacerbate the condition itself? Does the latissimus injury pose any risk to other parts of the shoulder (e.g., rotator cuff, labrum)?
Pitching through this may just prolong the symptoms or prevent it from getting better. It is uncommon for an injury such as this to directly propagate or lead to other aspects of the shoulder getting injured, such as the labrum or rotator cuff. However, if a player does try to "pitch through it" their mechanics may become altered to avoid the painful symptoms, which in turn may put stress on other parts of the shoulder and therefore may lead to further injury.
Thank you to Dr. Parsons for sharing his knowledge and insight on this matter.