A patient presents with a recurrent anterior shoulder dislocation. Milch fails but Spaso works. The next month she is back and the procedure feels different, with more resistance. This time Spaso fails and Milch works. Same shoulder, so what is different? Why did the efficacy reverse?
Milch’s 1938 article started with a question: why do some reductions seem impossible and then under general anesthesia they become very easy, almost going in spontaneously? It was the muscle and tendon opposition, he concluded, so his technique focused on putting the patient in the muscle neutral position overhead (hanging from a limb position). The various shoulder muscles would share equal stress and equal angles.
Milch’s idea has probably not yet been fully fulfilled – it was the idea that shoulder reduction is not about overcoming force but about untangling the humeral head from the adjacent muscles, tendons, and soft-tissues. That was the same idea that inspired Kocher.
We have all had the tough shoulder that would not go in with technique A, but after trying technique B, a second attempt with A yielded an effortless reduction. There seems to be an unlocking of the soft structures that occurs.
Now as to the unlocking. I suspect there is advantage in the difficult shoulder to running through a variety of techniques. Ideally we would know which soft structures are causing the locking, but the literature lacks consensus and I do not know to resolve that. So I run though a variety of techniques.
This is reductionistic but you can think of all techniques as the application of external rotation in different positions.
Kocher is external rotation in the adducted humerus, as are all the derivative techniques.
Milch is external rotation in the abducted elevated humerus (technically he advocated doing the external rotation on the way up).
Spaso is external rotation in the forward flexed shoulder.
Back to the bedside. Its your next shoulder attempt. The shoulder is locked in internal rotation. Your goal is to get it into external rotation. You try Kocher but there is too much resistance to external rotation. You laterally abduct to Milch and you came close but did not fully reduce the shoulder. Finally, you perform forward flexion (Spaso) which also does not work. You then go back to Kocher, which this time was successful.
Take Home Points:
-The obstruction to shoulder reduction is not bone position but soft structures
-The obstruction can apparently be unlocked through applying external rotation in various positions through the range of motion
-If your favorite technique does not work, range the shoulder, externally rotate, and try it again.
Check out medicalclassics.com for more on Milch. If the link does not work, here is the location. https://medicalclassics.com/2016/09/05/1938-milchs-shoulder-reduction-techniqueabduction-external-rotation-and-pulsion/