Pediatric Scaphoid Nonunions: A Case Series, Review of the Literature, and Evidence-Based Guidelines

Pediatric Wrist

Pediatric wrist injuries pose unique diagnostic challenges due to distinct bone characteristics in children and their diverse injury patterns. The dynamic development of the wrist, marked by changes in bone age and emerging ossification centers, is crucial to evaluate growth and identify potential pathologies. The skeletal composition, rich in cartilage, renders bones relatively weaker yet more elastic, impacting their susceptibility to fracture. Forearm fractures display diverse patterns influenced by torsional forces. Scaphoid fractures, less common in children, differ from those in adults. Conditions like Madelung's deformity and ulnar variance are more common wrist disorders in the pediatric population. In addition, the scarcity and nonspecificity of symptoms in those with tendon injuries and triangular fibrocartilage complex lesions can be diagnostically challenging. This article reviews pediatric wrist injuries, emphasizing ossification patterns, common fracture types, and developmental variants. Grasping these complexities in pediatric wrist development and associated pathologies is essential for precise diagnosis and treatment.

Paediatric fractures of carpal bones other than the scaphoid

OBJECTIVES

Fractures of carpal bones other than the scaphoid are rare in children. The aim of this study was to analyze results and identify risk factors for an unfavorable outcome.

MATERIAL AND METHODS

Children and adolescents up to the age of 16 years who sustained a carpal fracture other than in the scaphoid between 2004 and 2021 were reviewed in this single-center retrospective study.

RESULTS

In a series of 209 children and adolescents with carpal fractures, 22 had fractures other than the scaphoid. Mean age was 13 years (range 8-16) years, with a total of 41 fractures, with highest incidences for the capitate (10), trapezium (6), triquetrum (4) and pisiform (4). Twenty-nine of these 41 fractures were missed on initial X-ray. Non-displaced fractures were treated with a short arm spica cast including the thumb. Four patients were operated on for displacement fracture or carpometacarpal subluxation. All fractures united, and patients returned to full activities. At the final consultation at a median 14 months (range 6-89) post-injury, all patients with non-displaced fractures were free of symptoms, with excellent Mayo Wrist Scores (MWS). However, three patients with operated trapezium fractures developed early radiological signs of osteoarthritis, two of them with residual pain and MWS rated only good.

CONCLUSION

Non-displaced pediatric carpal fractures treated by forearm cast have excellent prognosis. Fractures of the trapezium with displacement or first carpometacarpal subluxation incur a risk of osteoarthritis despite anatomical reduction and internal fixation.

Outcomes of Pediatric Scaphoid Nonunions Treated With Distal Radius Cancellous Autograft

BACKGROUND

The optimal management of pediatric scaphoid fracture nonunions is controversial. We hypothesize that pediatric patients with scaphoid fracture nonunions will have favorable functional outcomes with the utilization of nonvascularized distal radius cancellous autograft with open reduction and internal fixation (ORIF).

METHODS

A review was performed from 2012 to 2017 identifying skeletally immature patients with scaphoid fracture nonunions treated with ORIF and nonvascularized distal radius cancellous autograft, including demographic data, mechanism of injury, length of time from injury to treatment, operative procedure, length of immobilization, time to union, and complications.

RESULTS

Ten patients (9 males, 1 female) met inclusion criteria. Mean age was 14.3 SD 1.5 years. The majority of fractures were sustained during sports or secondary to a fall. Mean time between injury and orthopaedic evaluation was 33 weeks (SD 20 wk). Eight fractures occurred at the waist, and 2 occurred at the proximal pole. Four patients had a humpback deformity, and three presented with a dorsal intercalated segmental instability deformity. Nine patients were treated with a single cannulated compression screw with distal radius autograft. One patient also received a single Kirschner wire fixation in addition to a single cannulated screw and graft. Patients underwent a mean postoperative immobilization period of 14 SD 5 weeks. Two patients received a bone stimulator postoperatively. Radiographic union was documented after initial surgery in nine patients, with mean time to union of 17 SD 5 weeks. The 1 patient with persistent radiographic nonunion underwent revision fixation and repeat nonvascularized distal radius autograft, achieving union and resolution of symptoms. All patients ultimately reported full return to activity.

CONCLUSIONS

Pediatric scaphoid fracture nonunions that undergo ORIF using nonvascularized distal radius cancellous autograft have favorable rates of consolidation and functional outcomes. Surgeons should consider this source of grafting in operative management of scaphoid nonunions in children and adolescents.

LEVEL OF EVIDENCE

Level IV, therapeutic.

Epidemiology of scaphoid fractures and non-unions: A systematic review

BACKGROUND

The scaphoid is the most commonly fractured carpal bone in adults as well as in children. Previous studies have reported a wide range of fracture incidences. Scaphoid fractures and non-unions in children have been sparsely investigated.

AIM

To perform a systematic review of the current literature on epidemiology of scaphoid fractures and non-unions in adults and children.

METHODS

An electronic literature search was conducted investigating all studies in the literature published between January 1989 and June 23 2020. The systematic review following the PRISMA guidelines and searching in PubMed, Embase, Web of Science and Cochrane library databases was done in June 2020.

RESULTS

42 studies met our inclusion criteria, 6 studies were prospective, 32 were retrospective and 4 were register studies. The majority of studies relied on conventional radiographs for diagnosis. Scaphoid fractures in adults are predominately found in males with a peak incidence in the age group from 20 to 29 years. Incidence rates in males are reported from 107 to 151/100 000. Females have an earlier peak, in the age group 10 to 19 years, with an incidence from 14 to 46/100 000. Most fractures occur in the middle third of the scaphoid representing 60-69 % of cases. Scaphoid fractures in children are predominately found in boys age 12 and above, while it seldomly occur for children younger than 9 years. In adults the risk for developing a scaphoid non-union is between 2 % and 5 %, the majority affecting males and predominately located at the middle third of the scaphoid. Non-unions among children are rare and mainly due to missed or delayed diagnosis of a fracture in the middle third of the scaphoid.

CONCLUSION

This review revealed a substantial heterogeneity among studies concerning study population, diagnosis criterial and outcome measures. Currently, evidence on epidemiology for scaphoid fractures and non-unions are low.