[MR imaging for the evaluation of accompanying injuries in cases of distal forearm fractures in children and adolescents]

Anatomy and injuries of the pediatric wrist: beyond the basics

Ligamentous injuries of the pediatric wrist, once thought to be relatively uncommon, are increasingly recognized in the context of acute high-energy mechanism trauma and chronic axial loading, including those encountered in both recreational and high-performance competitive sports. Recent advances in MR-based techniques for imaging the pediatric wrist allow for sensitive identification of these often radiographically occult injuries. Detailed knowledge of the intrinsic and supportive extrinsic ligamentous complexes, as well as normal developmental anatomy and congenital variation, are essential to accurately diagnose injuries to these structures. Early identification of ligamentous injury of the pediatric wrist is essential within the conservative treatment culture of modern pediatric orthopedics because treatment of these lesions often necessitates surgery, and outcomes often depend on early and sometimes aggressive intervention. In this article, we review MR arthrogram technique and pediatric wrist anatomy, and correlate appearances on MR and selected ligamentous pathologies of the pediatric wrist.

Ulnar styloid process nonunion and outcome in patients with a distal radius fracture: a meta-analysis of comparative clinical trials

PURPOSE

There is no consensus on the relation between ulnar styloid process nonunion and outcome in patients with distal radius fractures. The aim of this study was to analyze whether patient-reported outcome is influenced by the nonunion of the accompanying ulnar styloid fracture in distal radius fracture patients.

METHODS

A meta-analysis of published studies comparing outcomes after distal radius fractures with a united versus a non-united ulnar styloid process was performed. In addition, if provided by the authors, the raw data of these studies were pooled and analysed as one study. The outcome measures of the analyses included patient-reported outcome, functional outcome, grip-strength, pain, and distal radioulnar joint (DRUJ) instability.

RESULTS

Data from six comparative studies were included, concerning 365 patients with a distal radius fracture. One hundred and thirty-five patients with an ulnar styloid union were compared with 230 patients with a nonunion of the ulnar styloid. No significant differences were found between groups regarding any outcome measure.

CONCLUSION

Based on this meta-analysis, there is no relation between the nonunion of the ulnar styloid process and function in patients with a distal radius fracture.

Impact of ulnar styloid fractures in nonoperatively treated distal radius fractures

PURPOSE

The effect of an ulnar styloid fracture (USF) on the stability of nonoperatively treated distal radius fractures (DRF) is unknown. The aim of this study was to evaluate the influence of USFs on the dislocation of DRFs treated by closed reduction.

METHODS

Standardized radiographs of 100 nonoperatively treated DRFs were evaluated. DRFs with a USF were compared to DRFs without a USF with respect to dorsal tilt, radial inclination, and ulnar variance.

RESULTS

We evaluated the radiographs of 100 DRFs in 99 consecutive patients, of whom 84 were women. An accompanying USF was present in 58 wrists, of which 49 were displaced. On the trauma radiograph, the USF group showed significantly more overall dislocation. After closed reduction, fracture position improved, and no significant differences in dislocation were observed between groups. After a mean of 42 days, radial inclination significantly decreased if a USF was present. When USF displacement was taken into account, significantly more ulnar variance occurred in the displaced USF group on the trauma and follow-up radiograph compared to the nondisplaced USF group and no-USF group.

CONCLUSIONS

The results of this study show that presence of a dislocated USF in patients with a DRF is associated with a worse position directly after trauma, and with recurrence of radial shortening after adequate reduction. These results warrant early radiologic follow-up in patients with reduced combined DRFs and USFs in order to evaluate the redislocation of the distal radius. Early detection of redislocation in these combined fractures may induce early surgical intervention.

The Influence of Non-union of the Ulnar Styloid on Pain, Wrist Function and Instability after Distal Radius Fracture

The influence of non-union on the outcome of distal radius fractures is debated. We tested the null hypothesis that there is no difference in pain, wrist function, or instability between patients with union or non-union of an ulnar styloid base fracture after operative treatment of a fracture of the distal radius. Eighteen adults with an ulnar styloid base non-union were compared to 16 patients with union of an ulnar styloid base fracture with a mean post-operative follow-up of 30 months. None of the patients had distal radioulnar joint instability, there were no significant differences in pain, complications, or function, and patients with nonunion had significantly greater grip strength. Ulnar styloid nonunion is not associated with pain, instability, or diminished function after fracture of the distal radius.

The treatment of upper limb fractures in children and adolescents

BACKGROUND

The treatment of fractures in children and adolescents must be based on an adequate knowledge of the physiology of the growing skeleton. Treatment failures usually do not result from technical deficiencies, but rather from a misunderstanding of the special considerations applying to the treatment of fractures in this age group.

METHODS

We selectively reviewed recent publications on the main types of long bone fracture occurring in the period of skeletal development.

RESULTS

Alleviating pain is the first step in fracture management, and due attention must be paid to any evidence of child abuse. The goals of treatment are to bring about healing of the fracture and to preserve the function of the wounded limb. The growth that has yet to take place over the remaining period of skeletal development also has to be considered. Predicting the growth pattern of fractured bones is a basic task of the pediatric traumatologist. During the period of skeletal development, conservative and surgical treatments are used in complementary fashion. Particular expertise is needed to deal with fractures around the elbow, especially supracondylar humeral fractures, displaced fractures of the radial condyle of the humerus, radial neck fractures, and radial head dislocations (Monteggia lesions). These problems account for a large fraction of the avoidable cases of faulty fracture healing leading to functional impairment in children and adolescents.

CONCLUSION

The main requirements for the proper treatment of fractures in children and adolescents are the immediate alleviation of pain and the provision of effective treatment (either in the hospital or on an outpatient basis) to ensure the best possible outcome, while the associated costs and effort is kept to a minimum. Further important goals are a rapid recovery of mobility and the avoidance of late complications, such as restriction of the range of motion or growth disorders of the fractured bone. To achieve these goals, the treating physician should have the necessary expertise in all of the applicable conservative and surgical treatment methods and should be able to apply them for the proper indications.

Clinical impact of United versus nonunited fractures of the proximal half of the ulnar styloid following volar plate fixation of the distal radius

PURPOSE

Distal radius fractures are often associated with a fracture of the ulnar styloid at its base. This study tested the null hypothesis that there is no difference in outcome between patients with union and nonunion of a fracture of the proximal half of the ulnar styloid 6 months after volar plate fixation of a fracture of the distal radius.

METHODS

A total of 36 consecutive patients with fractures of both distal radius and the proximal half of the ulnar styloid enrolled in 1 of 2 clinical trials evaluating volar plate fixation of the distal radius had no treatment of the ulnar styloid fracture. Six months after surgery, wrist function was assessed using the Mayo wrist score and the Gartland and Werley score system, and arm-specific health status was measured using the Disabilities of the Arm, Shoulder, and Hand questionnaire. Pain was assessed on a 10-point ordinal scale. Nonunion of the fracture of the proximal half of the ulnar styloid was defined as no signs of consolidation on 6-month postoperative radiographs. At the 6-month follow-up, patients were assessed for overall wrist function but not specifically for ulnar-sided wrist problems or stability.

RESULTS

Sixteen ulnar styloid fractures had united, and 20 had not. There were no differences in demographic and injury characteristics. There were no significant differences in motion; strength; Gartland and Werley scores; Mayo scores; Disabilities of the Arm, Shoulder, and Hand scores; or pain scores 6 months after fracture.

CONCLUSIONS

Nonunion of a fracture of the proximal half of the ulnar styloid has no effect on wrist function, pain, and upper extremity-specific health status 6 months after volar plate fixation of a fracture of the distal radius.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic III.

Bone bruising of the distal forearm and wrist in children

Bone bruising represents a new category of bone injury that can only be demonstrated by magnetic resonance imaging (MRI) with fat suppression. This study proposed the nature of non-radiographically evident injuries of the distal radius and wrist in children whose symptoms did not resolve after 5 weeks. We aimed to describe and classify the lesions and delineate the importance and potential complications of the injuries. Bone bruising was diagnosed in 20 patients (mean age: 11.6 years; range: 9-13 years). Bone bruises were classified according to anatomical location and whether they were solitary lesions or were combined with other injuries. Injuries of the distal radius were classified according to location: type 1 was localised to the metaphysis, close to the physeal plate; type 2 involved both the metaphysis and diaphysis; and type 3 extended on both sides of the distal radial growth plate. The type 1 injuries were consistent with complete, un-displaced Salter-Harris type I fractures, whilst type 3 lesions were potentially Salter-Harris type V injuries. Our data indicate that an MRI should be considered for a child with an injury to the distal radius or wrist whose symptoms do not resolve after 5 weeks of immobilisation.

The effect of an associated ulnar styloid fracture on the outcome after fixation of a fracture of the distal radius

A total of 118 consecutive patients with a fracture of the distal radius were treated with a volar locking plate; 50 patients had no ulnar styloid fracture, 41 had a basal ulnar styloid fracture, and 27 had a fracture of the tip of the ulnar styloid. There were no significant differences in radiological and clinical results among the three groups. The outcome was good and was independent of the presence of a fracture of the ulnar styloid. A total of five patients (4.2%) had persistent ulnar-sided wrist pain at final follow-up. Nonunion of the ulnar styloid fracture did not necessarily lead to ulnar wrist pain. Patients with persistent ulnar pain had a higher mean initial ulnar variance and increased post-operative loss of ulnar variance.

The presence of an associated ulnar styloid fracture of the ulnar styloid does not adversely affect the outcome in patients with a fracture of the distal radius treated by volar plating.

Correction of forearm malunion guided by the preoperative complaint

Diaphyseal malunion of the forearm may cause loss of pronation and supination, a painful distal radioulnar joint, and aesthetic problems. Seventeen patients (10 males, seven females; mean age, 20.6 +/- 9.3 years) were operated on because of symptomatic malunion after a pediatric forearm fracture. Six patients had predominant loss of pronation (Group 1), four had predominant loss of supination (Group 2), and seven had a painful distal radioulnar joint (Group 3). An osteotomy of the radius was performed in seven patients and of both forearm bones in 10. All patients were available for clinical and radiologic assessments at a minimum followup of 6 months (mean +/- standard deviation, 3.7 +/- 2.3 years; range, 0.5-9.9 years). Release of the contracted interosseous membrane frequently was necessary for patients in Groups 1 and 2 to allow for correction and did not result in weakness, instability of the distal radioulnar joint, or synostosis. The overall improvement in range of motion after osteotomies for patients with a supination deficit was much better than in those with a pronation deficit. All patients in Group 3 gained a pain-free and stable distal radioulnar joint and their range of motion was unchanged. Therefore, ability to improve overall range of motion through forearm osteotomies is dependent on the patients' preoperative complaint.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.