Epidemiology of pediatric scaphoid fractures has changed

Scaphoid fracture care should be determined by fracture location, displacement and chronicity.

For this month’s 4 Questions interview, I asked Donald S. Bae, MD, to share some of his recent work and insights into pediatric scaphoid fractures. How many of these do you see in a year? My point is that none of us see many. It is important to recognize this injury and then evaluate the type of fracture. Dr. Bae’s responses give an approach and suggestions that will help you decide if you are going to treat the young patient or refer for a second opinion.

— Douglas W. Jackson, MD
Chief Medical Editor

Douglas W. Jackson, MD: What is the typical scaphoid fracture seen in the children and adolescents in your study and how are they best demonstrated?

Donald S. Bae, MD: Historically, scaphoid fractures in children were thought to affect predominantly the distal pole, requiring neither surgical treatment nor longer term follow-up. Based upon our recent analysis of patients treated from 1995 to 2010, however, the epidemiology of pediatric scaphoid fractures has changed.

At present, waist fractures are most common, representing approximately two-thirds of all scaphoid fractures in children and adolescents. Fractures of the distal pole represent approximately one-fourth of all injuries, and proximal pole fractures are the least common, accounting for only 6% of scaphoid fractures.

Most patients present acutely with wrist pain, limited motion, “anatomic snuffbox tenderness,” and positive diagnostic studies, including plain radiographs, CT and/or MRI scans. Interestingly, 29% of the patients in our study presented late with chronic nonunions. This highlights the importance of maintaining a high index of suspicion and obtaining appropriate radiographs in the evaluation of an adolescent with traumatic wrist pain.

Donald S. Bae

Jackson: What was the study population you and your co-authors reviewed in your recent article?

Bae: We performed a retrospective analysis of 351 scaphoid fractures in 342 patients treated at our institution from 1995 to 2010. Three hundred and twelve fractures had complete clinical and radiographic follow-up. Mean age was 14.6 years, and all patients were younger than 18 years of age. Information regarding patient demographics, mechanisms of injury, fracture acuity and pattern, treatment, and subsequent time to bony union were recorded.

Jackson: What is the standard treatment you recommend for most of these fractures?

Bae: Based upon our findings, we believe treatment of scaphoid fractures in children and adolescents should be determined by fracture location, displacement and chronicity. Acute nondisplaced fractures of the waist and distal pole may be effectively managed with cast immobilization, with expected healing rates of greater than 90%. Acute displaced fractures, as well as chronic fracture nonunions, should be treated with surgical reduction and internal fixation, with or without bone grafting, to maximize union rates.

Jackson: What was the reported experience for nonunions and how were they treated?

Bae: Scaphoid fracture nonunions present several clinical challenges. There are often cystic and resorptive changes at the nonunion site and secondary carpal instability patterns, resulting in the need for surgical reduction and structural bone grafting to restore wrist anatomy and mechanics. Furthermore, there are risks of osteonecrosis and subsequent arthrosis due to the inherent limited vascularity of the scaphoid.

Of the 312 fractures in our series with complete clinical and radiographic follow-up, there were 90 chronic nonunions. Mean time interval between injury and initiation of treatment was 26.8 weeks in this cohort. While 77 of the 90 chronic nonunions were initially treated with cast immobilization, only 23% went on to demonstration bony healing. Indeed, chronic fractures were approximately 30 times less likely to heal with cast immobilization than acute injuries. For these reasons, surgery should be considered the treatment of choice for scaphoid nonunions.

Surgical treatment for chronic scaphoid nonunions achieved bony healing in 96% of patients. Longer time to union after surgery was seen in more proximal fractures, displaced fractures, patients with open physes and cases where bone graft was needed.

Reference:

• Gholson JJ, Bae DS, Zurakowski D, Waters P. Scaphoid fractures in children and adolescents: Contemporary injury patterns and factors influencing time to union. J Bone Joint Surg Am. 2011;93:1210-1219.

• Donald S. Bae, MD, can be reached at Children’s Hospital Boston, Department of Orthopedic Surgery, 300 Longwood Ave., Hunnewell 2, Boston, MA 02115, 617-355-6808; fax: 617-730-0459; email: donald.bae@childrens.harvard.edu.
• Disclosure: Bae has no relevant financial disclosures.