Ultrasound
changes after rotator cuff repair: is supraspinatus tendon thickness related to
pain?

Tham
ER, Briggs L, Murrell GA.  J Shoulder
Elbow Surg. 2013 Jan 23. pii: S1058-2746(12)00523-X. doi:
10.1016/j.jse.2012.10.047. [Epub ahead of print]

Rotator
cuff tears are common injuries in overhead athletes causing a significant
increase in pain and decrease in function. 
Cuff tears commonly require surgical repair; however, the results after
surgery are mixed with both repair failures and successful repairs not having
significant pain relief.  These poor
outcomes may be related to anatomic adaptations at the shoulder following
rotator cuff repair but it is unclear what these adaptations may be and whether
they are related to pain.  Therefore, Tham
et al. evaluated whether there are changes in rotator cuff tendon thickness, subacromial
bursa thickness, tendon attachments, tendon vascularity, and posterior
glenohumeral capsule thickness after a rotator cuff repair and if tendon
thickness was related to pain. Among 57 patients that underwent a surgical
repair, the authors found 16 patients that had intact supraspinatus tendons
bilaterally.  They used diagnostic
ultrasound to measure several anatomic features on the involved (surgical) and
uninvolved shoulder as an internal healthy control.  Participants also completed a questionnaire
about pain.  Ultrasound measures and the
pain questionnaire were completed at 1, 6, 12, and 24 weeks post-surgery.  The authors found that bursa thickness,
vascularity, and posterior capsule thickness decreased from 1 to 24 weeks.  The anatomic footprint (tendon attachment)
increased from 1 to 24 weeks.  Compared
to the contralateral control, bursal and posterior capsule thickness were
significantly different at 1 week but that difference was not present by 6
weeks.  The participants’ shoulder pain
decreased overtime; however, there was no correlation between tendon thickness
and shoulder pain. 

This
is an interesting study that examines the anatomic changes that occur following
successful rotator cuff repairs.  Several
structures seem to go through a remolding stage as the tendon heals and the
joint returns to homeostasis.  The most
apparent adaptations that are occurring are decreases in bursal thickness and
vascularity.  Following surgical repair
there is an active tendon repair process occurring that requires a large amount
of signaling proteins and growth factors. 
These biologic factors are delivered from the bursa and increased blood
flow.  However, as the stages of healing
progress the presence of these biologic factors are decreased.  This is in agreement with the current studies
results.  The time points are very
clinically meaningful, demonstrating that the first 6 weeks are important for
successful healing (bursal thickness). 
In addition the authors observed a thick posterior capsule thickness early
after surgery, which decreased overtime. 
The authors were surprised by this finding and it suggests that the
entire joint experiences adaptions following surgery.  Specifically, this measure of posterior
capsule thickness may relate to post-operative shoulder stiffness.  In fact this was recently found to be true in healthy overhead athletes
Therefore, posterior capsule thickness may be a very useful measurement
to predict or identify patients that are suffering from shoulder
stiffness.  As clinicians we can optimize
the treatment of patients with thick posterior capsules and improve their short-
and long-term outcomes.  In the future it
would be interesting to examine the patients that had failed rotator cuff
repairs to identify if any of these adaptations were the cause.  Do you use diagnostic ultrasound throughout
rehab to track structural changes?  Do
you think there are anatomic adaptations that can help us strategize patient
care?

Written
by:  Stephen Thomas
Reviewed
by: Jeffrey Driban

Related
Post
:

Tham ER, Briggs L, & Murrell GA (2013). Ultrasound changes after rotator cuff repair: is supraspinatus tendon thickness related to pain? Journal of Shoulder and Elbow Surgery PMID: 23352550