Aforty-two-year-old, right-hand dominant, athletic man who worked as a
carpenter sustained an injury to the left shoulder while playing football. An
anteroposterior radiograph of the shoulder was interpreted as normal in an
emergency department, and treatment was started with pain medication and
application of a sling. A week later, he was reexamined and physiotherapy was
initiated. Despite physiotherapy and rest, the patient had pain and limitation
of shoulder movement. He was referred to our department three months after the
injury.
On clinical examination, the patient had painful restriction of both active
and passive glenohumeral movement in all directions. Abduction and forward
elevation was 50°, internal rotation was 40°, and there was no
external rotation. No neurovascular impairment was found, and the patient
reported incapacitating night pain. An anteroposterior radiograph of the
shoulder revealed a lightbulb
sign4, and a
computed tomography scan showed a locked posterior dislocation of the humeral
head with 25% to 30% impaction of the articular surface. A magnetic resonance
imaging scan was done to evaluate the capsuloligamentous structures of the
joint (Figs. 1-A,
1-B, and
1-C).
Under general anesthesia, the patient was placed in the lateral decubitus
position and a 10-cm straight incision was made from the posterior aspect of
the acromioclavicular joint toward the posterior axillary fold. Skin flaps
were raised, and the deltoid fibers were split in line, 2 to 3 cm medial to
the posterior border of the acromion. The two heads of the infraspinatus
muscle were then separated, starting from its lateral insertion up to 4 cm
medially. The posterior capsule was exposed and was found to be detached from
the posterior aspect of the glenoid rim. It was incised in a so-called
T-fashion, and the humeral head was exposed (Figs.
2-A,
2-B, and
2-C). A blunt periosteal
elevator was used to release adhesions and scarring in the anterior aspect of
the joint and to mobilize the humeral head. Traction was applied with the arm
held in internal rotation, and a retractor placed on the posterior aspect of
the glenoid rim was used to carefully lever the humeral head back in place
while the arm was gradually brought to full abduction and external rotation.
Once in place, the reduction was stable and no redislocation occurred when the
arm was placed in flexion, adduction, or internal rotation. The capsule was
then plicated and reattached to the glenoid rim and labrum with use of two
metal bone anchors with number-2 braided polyester sutures (Mitek, Norwood,
Massachusetts) with the arm held in neutral position and 30° of abduction.
Postoperatively, the arm was immobilized in 30° of abduction and in slight
external rotation, with use of a pillow and a sling for two weeks, and then it
was held in a simple sling for an additional two weeks. The patient was then
instructed to start active and passive range-of-motion exercises.
The patient regained painless shoulder function at three months and
painless, almost full, range of motion at six months postoperatively. He had
full abduction and internal rotation while external rotation was about 20°
less than that on the contralateral side. He then returned to full
occupational activities. At three years postoperatively, the patient had
almost full range of motion, no pain, no signs of instability, and complete
recovery of muscle strength. A magnetic resonance imaging scan showed healing
of the posterior capsule with no other apparent soft-tissue or osseous
abnormalities (Figs. 3-A,
3-B, and 3-C).
Several posterior approaches to the shoulder have been reported in the
literature5-7.
For our patient, a limited direct posterior anatomic reduction and repair was
planned and executed. The posterior deltoid-splitting approach, as described
by Wirth et al.6,
was used. The exposure of the posterior capsule was adequate, and the
reduction and capsular repair proved to be relatively easy. The reverse
Hill-Sachs lesion, which in our patient was 25% to 30% of the articular
surface, was left untreated following an intraoperative evaluation of joint
stability. Larger defects would probably need
bone-grafting1,8.
Our patient fully resumed his activities and regained almost full range of
motion. At three years postoperatively, he had no pain and no sign of
glenohumeral instability.
We suggest the use of a direct posterior reduction and reconstruction of a
neglected posterior dislocation of the shoulder through the posterior
deltoid-splitting approach after thorough imaging of the lesion with computed
tomography and magnetic resonance imaging scans. As far as we know, this
report is the first to describe treatment of a locked posterior dislocation of
the shoulder with this procedure. ?