Background: Recent studies have suggested that tenotomy and repair
of the subscapularis tendon carried out for anterior approaches to the
shoulder can be followed by failure of the tendon repair and by changes
resulting in permanent loss of subscapularis function. We hypothesized that
release of the subscapularis with use of a superficial osteotomy of the lesser
tuberosity followed by repair of the two opposing bone surfaces would lead to
consistent bone-to-bone healing, which would be possible to monitor
radiographically, and would lead to satisfactory clinical and structural
Methods: Thirty-nine shoulders in thirty-six consecutive patients
who, at an average age of fifty-seven years, had undergone total shoulder
replacement through an anterior approach involving an osteotomy of the lesser
tuberosity were evaluated at an average of thirty-nine months. Assessment
included a standardized interview and physical examination, scoring according
to the system described by Constant and Murley, and imaging with conventional
radiography and computed tomography to assess healing of the osteotomy site
and changes in the subscapularis.
Results: The osteotomized tuberosity fragment healed in an
anatomical position in all shoulders, and no cuff tendon ruptures were
observed. At the time of follow-up, thirty-three (89%) of thirty-seven
shoulders evaluated with a belly-press test had a negative result and
twenty-seven (75%) of thirty-six shoulders evaluated with a lift-off test had
an unequivocally normal result. Fatty infiltration of the subscapularis muscle
increased after the operation (p < 0.0001) and was at least stage two in
eleven (32%) of thirty-four shoulders. The fatty infiltration had progressed
by one stage in eight (24%) of the thirty-four shoulders, by two stages in
five shoulders (15%), and by three stages in two shoulders (6%).
Conclusions: Osteotomy of the lesser tuberosity provides an easy
anterior approach for total shoulder replacement and is followed by consistent
bone-to-bone healing, which can be monitored, and good subscapularis function.
In the presence of documented anatomical healing of the osteotomy site,
postoperative fatty infiltration of the subscapularis muscle remains
unexplained and needs to be investigated further as it is associated with a
poorer clinical outcome.
Level of Evidence: Therapeutic Level IV. See Instructions
to Authors for a complete description of levels of evidence.