Open Reduction and Internal Fixation of Posterior Fracture Dislocation of the Shoulder Made Easy!

INTRODUCTION: Posteriorly dislocated humeral head fracture has a great implication, as it is associated with high risk of avascular necrosis, limited access through the deltopectoral approach, and posterior approach to the posteriorly dislocated humeral fracture increases the risk to the remaining blood supply. TECHNICAL TIP: Posteriorly dislocated humeral fracture is approached through deltopectoral approach. Schanz pin is inserted into the humeral head to achieve purchase in the humeral head. Applying laterally directed force the humeral head is disengaged from the lateral margin of glenoid. A rotatory force then repositions the humeral head into a congruous position. Open reduction internal fixation is then carried out in a standard fashion.
CONCLUSION: Retrieving the humeral head from the posteriorly dislocated position in patients with posterior fracture dislocation of the shoulder can be challenge to a trauma surgeon. With this novel technique, humeral head is reduced through deltopectoral approach without increasing the risk to the remaining blood supply.

Posterior dislocated humeral fracture can be reduced by schanz screw through deltopectoral approach without increasing risk to remaining blood supply.

Introduction

Proximal humeral fractures rank as second most common fractures of the upper extremity accounting for 4–5% of all fractures [1]. About 20% of displaced proximal humeral fractures require surgery [2]. However, functional outcome mainly depends on the age of the patient and less on the deformity [3, 4]. In fractures where adequate reduction and stable fixation cannot be achieved, and the vascularity of the head fragment is impaired or at risk, primary arthroplasty has to consider. Using anterograde, intramedullary nailing for complex fractures has considerable disadvantage of affecting rotator cuff function. For fractures where there is no significant displacement of the tuberosities, intramedullary locking nails are best option to consider in displaced two-part fractures or three- and four-part fractures [5]. Locking plate fixation has proved to be the gold standard, especially when the displacement of the tuberosities is present.

Retrieving locked posteriorly dislocated humeral head can be a challenge from an anterior deltopectoral approach [6]. Insertion of rotator cuff, biceps tendon and neighboring neurovascular structures, and extramedullary fixation of proximal humeral fractures mainly has to be approached from lateral aspect [7, 8]. Only way to achieve reduction ofthe medial fracture zone is through indirect manipulation or across the fracture line [9]. Fluoroscopy is mandatory as direct visual control is not possible [9]. Posteriorly dislocated humeral head fracture and associated comminution has a great implication as it is associated with high risk of avascular necrosis [10]. The standard deltopectoral approach provides limited access to the posterior aspect of the proximal humerus [11] and posterior approach to the posteriorly dislocated humeral fracture increases the risk to the remaining blood supply. This poses a dilemma for the operating surgeon. We suggest a technical tip to help reduce the humeral head without increasing the risk to the remaining blood supply

3D computed tomography reconstruction.

Technical Tip

Posteriorly dislocated humeral fracture (Fig. 1 and 2) is approached through deltopectoral approach. Schanz screws are intended for use with external fixator system. With the help of universal drill chuck with a T-handle, Schanz screw is manually screwed into the middle of the fracture surface the posteriorly dislocated humeral head to achieve purchase in the humeral head (Fig. 3). Applying laterally directed force, the humeral head is disengaged from the lateral margin of the glenoid (Fig. 4). A rotatory force then repositions the humeral head into a congruous position. Open reduction internal fixation is then carried out in a standard fashion.

Figure 1

Computed tomography scan of the posteriorly dislocated proximal humerus fracture with fragment engaged on glenoid

Figure 3

Diagram showing engaged posteriorly dislocated humeral fracture.

Figure 4

Diagram showing disengaged posteriorly dislocated humeral fracture.

Discussion

Undisplaced proximal humerus fractures which can be treated and managed non-operatively with favorable outcome, fractures with intra-articular extension and severe comminution require surgical fixation [2, 12]. Fracture reduction is of paramount importance in orthopedic surgery which holds true even for proximal humerus fracture [13].

Conclusion

During the deltopectoral approach, soft-tissue stripping damage the local blood supply and integrity of deltoid, which may increase the risk of avascular necrosis and delay postoperative functional recovery [14, 15, 16]. Retrieving the humeral head from the posteriorly dislocated position in patients with posterior fracture dislocation of the shoulder can be challenge to a trauma surgeon.

With this novel technique, the humeral head is reduced via deltopectoral approach without increasing the risk to the remaining blood supply.