Management of Nonunion Following Surgical Management of Scaphoid Fractures: Current Concepts

Abstract

Management of scaphoid nonunion after failed surgery for acute scaphoid fracture presents a unique treatment challenge. Prior surgery complicates patient evaluation and increases the technical difficulty of future procedures. Healing of nonunion is crucial to prevent carpal collapse and progressive arthritis. A thorough workup is required to identify technical factors or treatment decisions that may have resulted in a poor outcome after initial fixation attempts. CT is particularly useful for characterizing nonunion and planning revision surgery. Several studies have described the use of bone grafts and fixation devices for scaphoid nonunion repair, including nonvascularized and vascularized bone grafts, screws, pins, and plates. Reliable rates of union have been achieved using nonvascularized bone graft supplemented with screw or wire fixation, particularly in the absence of osteonecrosis. Although vascularized grafts are more technically challenging, they improve the odds of union in the setting of osteonecrosis.

Treatment of chronic (>1 year) fracture nonunion: Heal rate in a cohort of 767 patients treated with low-intensity pulsed ultrasound (LIPUS)

“…In short, patients may fail revision surgery for the same reasons that they failed initial surgery. Surgical revision is also technically difficult [15] and carries risks inherent to any surgery. Therefore, a non-surgical option for treating fracture nonunion could be useful, especially if it was effective in the presence of risk factors for surgical failure.…”

Current Fixation Options for Elbow, Forearm, Wrist, and Hand Fractures

“…For nonunited fractures that were initially managed surgically, management options include nonvascularized bone grafting (typically from the distal radius or iliac crest), vascularized bone grafting, arterialization, and plate fixation. 108 If screw malalignment and/or fracture malreduction is present, the screw fixation may be revised. Nonvascularized bone grafts heal by creeping substitution and resorption that may result in decreased stability and longer time to union as compared with vascularized bone grafting.…”

“…Vascularized bone grafting (which is a more technically difficult procedure) is particularly useful in cases of nonunion with osteonecrosis. 108 Arterialization involves direct implantation of additional arterial supply to the scaphoid (via the second dorsal intermetacarpal artery or dorsal index artery) and may be useful in cases in which prior bone grafting has limited the possible donor sites for vascularized bone grafting. 108 Although plate fixation may impinge the articular cartilage and/or require ultimate removal, it can provide torsional stability and may be helpful in managing nonunion with pseudoarthrosis.…”

“…108 Arterialization involves direct implantation of additional arterial supply to the scaphoid (via the second dorsal intermetacarpal artery or dorsal index artery) and may be useful in cases in which prior bone grafting has limited the possible donor sites for vascularized bone grafting. 108 Although plate fixation may impinge the articular cartilage and/or require ultimate removal, it can provide torsional stability and may be helpful in managing nonunion with pseudoarthrosis. 108,109 Scaphoid nonunion predictably results in delayed osteoarthrosis of the radioscaphoid joint and ultimately the entire wrist with use over time postinjury.…”

A Biomechanical Comparison of Screw and Plate Fixations for Scaphoid Fractures

“…13,14 Scaphoid nonunion fixation is frequently augmented with bone grafting. 4,8 Cancellous graft is the optimal graft choice because of its biologic properties. 15 However, cancellous graft does not provide the structural integrity that cortical or corticocancellous grafts provide.…”