A 64 y/o F non smoker presented with a proximal fracture / anterior shoulder dislocation. At the time of presentation she was neuro-vascularly intact. The mechanism of injury was a mechanical fall on the ground during walking.
Preoperative evaluation demonstrated a fracture of the proximal humerus with an anterior dislocation. In most situations and in the acute settings -ie ER environment- it is difficult to obtain good Grashey x-rays of the shoulder. She had a CT scan that was used to verify the dislocation seen on the scapular Y view (anterior dislocation) and also help with the treatment algorithm ie fixation vs arthroplasty.
Preoperative XRs and CT scan are shown below:
The AP shoulder x-ray is "suspicious" of dislocation based on the overlap of the humeral head to the glenoid (projection). The scapular Y XR demonstates the anterior humeral head dislocation. The CT confirms that there is no head split from the dislocation or fracture and that the head is dislocated anteriorly.
Fixation of the fracture requires
(1) Elimination of the varus inclination
(2) Reduction of the dislocation
(3) Fixation of the greater tuberosity fragment to the head.
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Reduction of the dislocation was performed with minimal soft tissue dissection. After the exposure of the fracture site through a deltopectoral approach a heavy Steinman Pin was inserted to the head of the humerus from an anterior to posterior direction. This pin was used for (1) Reduction of the dislocation and manipulation and alignment of the fracture relative to the shaft on the coronal plane. After the reduction two K wires were used for head-to-shaft provisional fixation and one K-wire for greater tuberosity to head fixation. |
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The construct was finished with a 3.5mm locking plate with the following goals
(1) Restoration of head to neck and shaft angle-Avoid varus or valgus
(2) Verification on the axillary view that the dislocation was reduced
(3) Stable fixation at the medial calcar with no step off ideally with at least one or two calcar locking screws.
Of note if there was a small <25% glenoid bony Bankart lesion then FIXATION IS NOT NECESSARY. Most of the time the postoperative stiffness compensates for the potentially instability. Fixation of the glenoid would contribute to the stiffness that is an associated problem in proximal fracture fixation |
Posterior fracture dislocations are approached using the same principles. Most of the time these injuries are the result of seizure disorders. For the young patient with preserved humeral head (>85%), open reduction and internal fixation (ORIF) may be the treatment of choice, although it remains unclear whether the hemi-arthroplasty or the ORIF is superior in achieving an acceptable outcome without the need for subsequent surgery. Most ORIF cases are revised for AVN, stiffness or failure of the construct. Most hemi-arthroplasties for non healing of the tuberosities, limited motion, instability, or infection. It is desirable to avoid replacement if the anatomy of the proximal humerus can be restored with ORIF and cancellous or cortical bone grafting. An unstable or dislocated hemi-arthroplasty due to uncontrolled seizures is a very difficult problem to treat and the only available option would be a conversion to a reverse shoulder replacement which could also be complicated by instability. Images below demonstrate a case that was approached with ORIF although by radiographic criteria a hemiarthoplasty could have been offered as well.
After reduction of the dislocated humeral head it is demonstrated that there is bone loss at the greater tuberosity area.
The fibular allograft was placed laterally instead of medially (calcar area) because the bone loss was more severe laterally closer to the greater tuberosity.