This retrospective cohort asks whether preoperative fatty infiltration of the teres minor predicts outcome after reverse total shoulder arthroplasty. 42 shoulders treated with a Delta-III prosthesis were graded on MRI using the Goutallier system and stratified into low (stage 0-2) and high (stage 3-4) infiltration groups. Outcomes were compared with the Constant score, subjective shoulder value, and external rotation.
The clinical rule here is simple: before you counsel a patient for a reverse shoulder, look at the teres minor on the sagittal MRI. Stage 3 or 4 Goutallier infiltration means the posterior cuff is gone, and the deltoid-powered prosthesis cannot replace it. These patients keep overhead elevation but lose the ability to position the hand in space.
The mental model: the reverse prosthesis is a deltoid engine for flexion and abduction, but external rotation still depends on a functioning teres minor. No teres minor, no external rotation, and sometimes a net loss.
Warn patients who use the arm with the elbow abducted that they may function worse if control of external rotation is lost. The authors responded to this data by adding a concurrent latissimus dorsi transfer when teres minor infiltration exceeds stage 2 with a hornblower sign or external rotation lag.
Goutallier grading is reproducible (kappa 0.73), making it a practical preoperative decision tool.
This retrospective cohort asks whether preoperative fatty infiltration of the teres minor predicts outcome after reverse total shoulder arthroplasty. 42 shoulders treated with a Delta-III prosthesis were graded on MRI using the Goutallier system and stratified into low (stage 0-2) and high (stage 3-4) infiltration groups. Outcomes were compared with the Constant score, subjective shoulder value, and external rotation.
The clinical rule here is simple: before you counsel a patient for a reverse shoulder, look at the teres minor on the sagittal MRI. Stage 3 or 4 Goutallier infiltration means the posterior cuff is gone, and the deltoid-powered prosthesis cannot replace it. These patients keep overhead elevation but lose the ability to position the hand in space.
The mental model: the reverse prosthesis is a deltoid engine for flexion and abduction, but external rotation still depends on a functioning teres minor. No teres minor, no external rotation, and sometimes a net loss.
Warn patients who use the arm with the elbow abducted that they may function worse if control of external rotation is lost. The authors responded to this data by adding a concurrent latissimus dorsi transfer when teres minor infiltration exceeds stage 2 with a hornblower sign or external rotation lag.
Goutallier grading is reproducible (kappa 0.73), making it a practical preoperative decision tool.