Background: The purpose of this study was to evaluate the clinical
results of latissimus dorsi tendon transfer in patients with an irreparable
posterosuperior rotator cuff tear to help determine which patient and anatomic
factors affect clinical outcome.
Methods: Fourteen patients with a latissimus dorsi tendon transfer
were clinically evaluated with use of the PENN (University of Pennsylvania)
shoulder score as well as with quantitative measurement of isometric muscle
strength and the range of motion of both shoulders at a minimum of twenty-four
months postoperatively. The anatomic results were evaluated with postoperative
magnetic resonance imaging and electromyography.
Results: Nine patients were satisfied with the outcome, had
significant clinical improvement, and reported that they would have the
operation again under similar circumstances. The other five patients were
dissatisfied with the result and had significantly worse PENN scores, active
elevation, and objective measures of strength. Eight of the nine patients with
a good clinical result were male, and four of the five with a poor result were
female. Patients with a good clinical result had had significantly better
preoperative function in active forward flexion and active external rotation
compared with the patients with a poor result. The magnetic resonance imaging
demonstrated healing of the tendon to the greater tuberosity in twelve
patients and equivocal healing in two. There was no significant atrophy of any
of the transferred muscles. Electromyography demonstrated clear activity in
the transferred latissimus muscle during humeral adduction in all fourteen
patients, some electrical activity with active forward elevation in only one
patient, and some electrical activity with active external rotation in six of
the nine patients with a good clinical result. None of the patients with a
poor clinical result demonstrated electrical activity of the transferred
muscle with active forward flexion or external rotation.
Conclusions: Synchronous in-phase contraction of the transferred
latissimus dorsi is a variable finding following the surgical treatment of
irreparable posterosuperior rotator cuff tears, but when it is present it is
associated with a better clinical result. Preoperative shoulder function and
general strength influence the clinical result. Female patients with poor
shoulder function and generalized muscle weakness prior to surgery have a
greater likelihood of having a poor clinical result.
Level of Evidence: Prognostic Level II. See Instructions
to Authors for a complete description of levels of evidence.