Objective: To report experience with use of humeral locked nails in treating humeral delayed unions and nonunions. The following techniques yielded encouragingly good results: static locking, short-to-long segment nailing, bone grafting, fracture compression, and minimal surgical trauma.
Design and Methods: A total of 41 consecutive patients with 13 delayed unions and 28 nonunions were treated with humeral locked nails. Delay from trauma to surgery averaged 4.2 months for delayed union and 15.5 months for nonunion. The average age of patients was 50.2 years; average follow-up time was 23.2 months. There were 7 proximal-third fractures, 21 middle-third fractures, and 13 distal-third fractures. The antegrade approach was used for 13 fractures and retrograde for 28. Open nailing was performed in 39 fractures and closed nailing in 2. If the fracture motion was still present after nail insertion, axial compression of the fracture site was specially applied. Bone grafting was performed in the fractures with open nailing. Thirty-four fractures were nailed with 8-mm nails, and 7 fractures were nailed with 7-mm nails.
Results: With a single operation, all but two patients achieved osseous union in, on average, 5.6 months. One of these two patients eventually gained union after another surgery with fracture compression along the original nail and concurrent bone grafting. The second patient, undergoing hemodialysis for chronic renal failure, had persistent nonunion. At follow-up, for patients with antegrade nailing, all but four patients had less than 20 degrees limitation of shoulder abduction. For patients with retrograde nailing, all but two had less than 10 degrees limitation of elbow motion. Only the patient with persistent nonunion had continual pain and significant impairment of arm function.
Conclusions: Humeral locked nailing seems to be effective for humeral delayed unions or nonunions. It may be an acceptable alternative for fractures unsuited for plate fixation, such as those with comminution, osteoporosis, or a severely adhered radial nerve.
Despite operative or nonoperative means of treatment, certain humeral shaft fractures are slow to heal, some even failing to heal. 1–9 Surgery, the most generally accepted method of treatment for these difficult problems, continues to be fraught with complications. 10–12
Various operative treatments of humeral delayed unions or nonunions have been reported with different success rates and complications. 1,3,10,11,13–20 Compression plating, with its high union rate and good functional recovery, has been the most common practice of late. 10,14,19 However, this procedure has the disadvantages of extensive soft-tissue dissection, unsightly scarring, and risk of radial nerve injury. 15,18,20–23 Additionally, the rugged bone surface at the nonunion site also makes contouring of the plate more difficult. 23 For patients with osteoporosis, the screw purchase on the bone is unreliable and prone to failure. 20–25 Moreover, among patients who need removal of the plate, operation on the severely adhered or scarred soft tissue surrounding the nerve carries an even higher risk of radial nerve injury and causes more healing problems. 24
Compared with plating, intramedullary nailing has the advantages of less soft-tissue trauma and less postoperative infection. It is particularly beneficial for acute fractures or nonunions that are associated with osteoporosis or bone comminution, 16,24 and for patients requiring crutch walking. 8,15 However, unlocked nailing is complicated by poor rotational control of nails. 1,3,8,22,25,26 Unlocked nailing can be an alternative for certain selected delayed unions but is not recommended for nonunions. 18,19 Recently, the Seidel locked nail, with its improved rotational stability, has been used for delayed union and nonunion, 17 but resulting impairment of shoulder function and less than satisfactory fixation of the spreading mechanism have discouraged its use, especially for atrophic nonunions. 17,26–28
To date, there have been very few reports of the use of locked nails with transfixing locking screws at both ends to treat humeral delayed unions or nonunions, and results have been inconsistent. 11,15 In this study, the authors describe their experience in surgically treating humeral fractures of this sort with the use of a cannulated humeral locked nail, which was designed and manufactured at the National Taiwan University Hospital. The device has a small diameter for less tissue trauma and transfixing screws for more reliable stability. 24,29,30