Session I - Upper Extremity

Nerve Injury after Greater Tuberosity Fracture Dislocation

Ashima Garg, MD; Margaret M. McQueen, MD; Charles M. Court-Brown, MD, Royal Infirmary of Edinburgh, Edinburgh, Scotland

Objective: To determine the incidence of nerve injury after isolated greater tuberosity fracture dislocation of the proximal humerus and its recovery rate.

Method: Fifty consecutive isolated greater tuberosity fracture dislocations were prospectively followed. Radiographs and clinical examination were done at the time of injury, 2, 13, 26, and 52 weeks after. All patients were seen by an orthopaedic trauma surgeon.

Results: Forty-seven of the fifty patients were available for follow-up. There were 24 men and 23 women with an average age of 58 years (23-85 years). Forty-four patients were right-hand dominant (93.6%), yet only 25 patients (53.2%) injured their dominant side. Forty-six fractures had an anterior dislocation and one was an inferior dislocation. Looking at all 47 fractures, the maximum pre-reduction greater tuberosity fracture displacement varied from 2 to 32mm and averaged 11mm, and after reduction the displacement varied from 1 to 20mm for an average of 3mm.

There were 16 nerve injuries: 10 axillary, 3 brachial plexus, 1 median, and 1 ulnar. Three injuries did not recover. The average time for recovery was 9 weeks (2-24 weeks) for the remaining 13 nerve injuries. Six patients underwent surgery for displacements greater than 10mm post-reduction: greater tuberosity reduction and screw placement (2) or greater tuberosity excision and rotator cuff repair (4). Four patients who did not undergo surgical intervention developed shoulder impingement syndrome 3 or 6 months after injury, and all recovered without any surgical intervention after 6 months.

Two patterns of greater tuberosity fractures were seen: 21 had marked comminution of the greater tuberosity fragment, while 24 had a large fragment present. The average maximum pre-reduction and post-reduction displacement between the two groups did not vary. Pre-reduction it was 10 and 13mm for the comminution and large fragment groups, respectively, and post-reduction it was 3 and 2mm for each group. Functional outcome, as assessed by the Neer score, was also similar throughout the year in both groups. Only a satisfactory outcome (Neer score 80-89) was achieved one year after injury: 85 in the comminuted group and 82 in the large fragment group.

Conclusion: Isolated greater tuberosity fracture dislocation is not a benign injury and has a 34% risk of nerve injury with only a 81.2% recovery rate.