Non-union is a challenging complication of distal humerus fractures and has a reported incidence of 8% to 25% in recent series.1-6 The most important factor for hardware failure is poor initial fixation, which can be difficult to achieve in the presence of extensive comminution and osteopenia. Recent advances in surgical techniques and implant fixation, such as pre-contoured locking plates, have lessened the incidence of hardware failure and humeral non-union.7,8 Other contributing factors to non-union include smoking, poor soft tissue envelope, medication that inhibits bone formation, immunosuppression, and poor compliance with postoperative rehabilitation protocols.
Most non-unions occur at the supracondylar level, and the articular components may be healed in their reduced position (Figures 1a-1b). Bone stock may be severely compromised secondary to ongoing bone reabsorption. Loose hardware may further accelerate bone loss by a "windshield wiper" effect. A synovial pseudarthrosis may develop, characterized by reactive sclerosis on both sides of the non-union, erosion, and bone reabsorption of the distal fragment. Capsular contracture invariably develops in the presence of a non-union.
Figures 1a-1b. Non-union at supracondylar level
Review of all previous imaging will allow better understanding of the fracture pattern and quality of initial fixation. Standard AP and lateral radiographs help determine whether enough bone stock remains to warrant internal fixation or if total elbow arthroplasty is required. If internal fixation is considered, a CT scan with three-dimensional reconstruction is valuable to assess remaining bone stock and articular congruity and to aid in preoperative planning.
Suspected infection should be further investigated by assessment of white blood count, erythrocyte sedimentation rate, C-reactive protein, and aspiration of the joint and nonunion site.
Open reduction with stable internal fixation is the treatment of choice for most patients with adequate remaining bone stock (Figures 2a-2b). Utilizing a previous posterior midline incision will facilitate the revision operation. A posterior midline incision can still be considered in the presence of previous medial and lateral incisions if the soft tissue envelope is adequate.
Figures 2a-2b. Post-revision ORIF with medial and lateral plating technique (images courtesy of Dr. G. King)
Transposition of the ulnar nerve is recommended. Many patients will have had a transposition with their index procedure. If a previously transposed nerve is asymptomatic, further dissection should be avoided unless extended exposure is required to carry out the procedure. However, if the previous ulnar nerve transposition is symptomatic, neurolysis may result in improved outcome.9
There are a number of options for deep surgical exposure, and the choice is influenced by the index surgical approach. An olecranon osteotomy offers excellent exposure.10 The olecranon osteotomy should be elevated carefully, as existing fibrosis can tear the trochlear hyaline cartilage off the subchondral bone.11 The bilatero-tricipital approach (working on either side of the triceps) can be used for extra-articular non-union.12 A triceps reflecting (Bryan-Morrey)13 or TRAP14 (triceps reflecting anconeus pedicle) can be utilized; both are useful approaches if one anticipates the possibility of converting from internal fixation to total elbow arthroplasty intra-operatively. Adequate release of the contracture (including the anterior capsule, posterior capsule, and posterior bundle of the medial collateral ligament) is essential to regain full motion and decrease stress transmitted to the non-union site.
Current standard principles for ORIF of acute fractures should also be utilized for non-unions.1,8 Bone reabsorption may necessitate metaphyseal shortening, in which case the distal fragment should be translated anteriorly to allow room for the coronoid and the radial head during elbow flexion. A new olecranon fossa may need to be excavated to facilitate extension.1 Parallel plates are applied medially and laterally,1,8 and a third posterolateral plate can be considered.15 Autogenous cancellous bone graft or osteoinductive bone graft substitute can be placed in the non-union site. The need for structural graft is dictated by the extent and the location of bone loss.
Careful surgical technique, modern implants, and attention to capsular contracture and the ulnar nerve have resulted in improved outcomes in the recent literature.1,7 Helfet et al7 reported union in 51 of 52 patients with a final arc of motion of 94 degrees. However, 30% of patients required further surgery for hardware removal, contracture, or ulnar nerve symptoms. Suboptimal results have been reported with unstable and osteochondral non-unions.16,17
Total elbow arthroplasty is an excellent option for patients with fracture non-unions not amenable to ORIF. Indications include low-demand older patients with pre-existing cartilage pathology or patients with distal non-unions, severe osteopenia, bone loss, and articular damage. Total elbow arthroplasty has provided good results in appropriately selected patients.18,19,20 Cil et al20 reviewed 92 consecutive elbow replacements for non-union with an average follow-up off 6.5 years. Seventy-nine percent of patients reported minimal to no pain, with 85% patient satisfaction. Aseptic loosening was the most frequent implant complication (n=16), followed by implant fracture. Implant survivorship was reported as 96% at 2 years, 82% at 5 years, and 65% at 10 and 15 years. Risk of failure was increased in patients less than 65 years of age, and those with multiple previous surgeries and history of infection.
Distal humeral non-unions remain a challenging problem and are most often a result of poor initial fixation. Most non-unions can be addressed by stable internal fixation with modern surgical implants, capsular contracture release, and careful evaluation of the ulnar nerve. Total elbow arthroplasty is an effective salvage procedure in select patients.
- Sanchez-Sotelo J, Torchia ME, O’Driscoll SW. Complex distal humeral fractures: Internal fixation with a principle-based parallel-plate technique. J Bone Joint Surg Am 2007;89:961-969
- Henly MB. Intra-articular distal humeral fractures in adults. Orthop Clin North Am 1987;18:11-23
- McKee MD, Wilson TL, Winston L, Schemitsch EH, Richards RR. Functional outcome following surgical treatment of intra-articular distal humeral fractures through a posterior approach. Bone Joint Surg Am 2000;82:1701-1701
- Pajarinen J, Bjorkenheim JM. Operative treatment of type C intercondylar fractures of the distal humerus: Results after a mean follow-up of 2 years in a series of 18 patients. J Shoulder Elbow Surg 2002;11:48-52
- Sanders RA, Raney EM, Pipkin S. Operative treatment of bicondylar intraarticular fractures of the distal humerus. Orthopedics 1992;15:159-163
- Soon JL, Chan BK, Low CO. Surgical fixation of intra-articular fractures of the distal humerus in adults. Injury 2004;35:44-54
- Helfet D, Kloen P, Anand N, Rosen H. Open Reduction and Internal Fixation of Delayed Unions and Nonunions of Fractures of the Distal Part of the Humerus. J Bone Joint Surg Am 2003;85:33-40
- Sanchez-Sotelo J, Torchia ME, O’Driscoll SW. Complex distal humeral fractures: Internal fixation with a principle-based parallel-plate technique. Surgical Technique. J Bone Joint Surg Am 2008;90:31-46
- McKee M, Jupiter J, Bosse G. Outcome of neurolysis during post traumatic reconstruction of the elbow. J Bone Joint Surg Br 1998;80B:100-105
- Ring D, Gulotta L, Chin K. Olecranon osteotomy for exposure of fractures and nonunions of the distal humerus. J Orthop Trauma 2004;18:446-44
- Jupiter J. The management of nonunion and malunion of the distal humerus – A 30 year experience. J Orthop Trauma 2008;22:742-750
- Alonso-Llamas M. Bilaterottricipital approach to the elbow: It’s application in the osteosynthesis of supracondylar fractures of the humerus in children. Acta Orthop Scand 1072;43:479-490
- Bryan R. Morrey B. Extensive posterior exposure of the elbow. A triceps sparing approach. Clin Orthop Relat Res 1982;166:188-192
- O’Driscoll S. The triceps reflecting anconeus pedicle (TRAP) approach for distal humeral fractures and nonunions. Orthop Clin North Am 2000;31:91-101
- Jupiter J, Goodman I. The management of complex distal humerus nonunion in the elderly by elbow capsulectomy, triple plating, and ulnar nerve neurolysis. J Shoulder Elbow Surg 1992;1:37-46
- Ring D, Gulotta L, Jupiter J. Unstable nonunions of the distal part of the humerus. J Bone Joint Surg Am 2003;85A:1040-1046
- Ring D, Jupiter J. Operative treatment of osteochondral nonunion of the distal humerus. J Orthop Trauma 2006;20:56-59
- Figgie M, Inglis A, Mow C, Figgie H. Salvage of non-union of supracondylar fracture of the humerus by total elbow arthroplasty. J Bone Joint Surg Am 1989;71:108-65
- Morry B, Adams R. Semiconstrained elbow replacement for distal humeral nonunion. J Bone Joint Surg Br 1995;77:67-72
- Cil A, Veillette C, Sanchez-Sotelo J, Morrey B. Linked elbow replacement: A salvage procedure for distal humeral nonunion. J Bone Joint Surg Am 2008;90:1939-1950
Reprinted with permission from the Summer 2010 issue of COA Bulletin