The Diagnostic Utility and Clinical Implications of Wrist MRI in the Pediatric Population

Etiology and Diagnostic Challenges of Ulnar Wrist Pain in Pediatric and Adolescent Patients

PURPOSE

Diagnosing the cause of ulnar-sided wrist pain can be difficult in the pediatric and adolescent age group. While frequently used, the diagnostic accuracy of magnetic resonance image (MRI), as compared with intraoperative arthroscopic findings, is not well-described in this population. This study aimed to determine concordance rates between magnetic resonance and arthroscopic findings depending on the specific ulnar wrist pathology.

METHODS

A retrospective review was performed to identify pediatric and adolescent patients who underwent operative treatment of ulnar wrist pain between 2004 and 2021. Patients were included in the analysis if they were <18 years of age, complained of ulnar-sided wrist pain, underwent MRI of the affected wrist with an available report interpreted by a consultant radiologist, and had a diagnostic arthroscopy procedure within one year of imaging. Ulnar pathologies analyzed included triangular fibrocartilage (TFCC) tears, ulnotriquetral (UT) ligament tears, lunotriquetral ligament abnormalities, and ulnocarpal impaction.

RESULTS

A total of 40 patients with a mean age of 15-years-old (range 11 to 17) were included in the analysis. Twenty-four were female, and approximately half had their dominant extremity affected. Most had a history of antecedent trauma (n = 34, 85%), but only 15/40 (38%) had a history of fracture. The mean duration of symptoms prior to presentation was six months (standard deviation, 7). The most common etiologies were Palmer 1B TFCC tears (n = 27, 68%) followed by UT split tears (n = 11, 28%). MRI overall demonstrated high specificity (82% to 94%), but low sensitivity (14% to 71%) for ulnar-sided wrist conditions. Accuracy varied between 70% and 83% depending on the specific injury.

CONCLUSION

While MRI is a useful adjunct for determining the cause of ulnar wrist pathologies, findings are often discordant when compared with diagnostic arthroscopy. Surgeons should have a high degree of suspicion for TFCC-related pathology in the setting of positive provocative clinical examination despite negative MRI findings in young patients.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic IIb.

Pediatric Ulnar-sided Wrist Pain: A Review of the Current Literature

Patients presenting with ulnar-sided wrist pain can pose a diagnostic and therapeutic challenge to physicians because there are several pathologies with similar signs and symptoms. In comparison with adult patients, other etiologies must be considered in the pediatric patient, given the skeletal immaturity and potential for known or unrecognized syndromes. In addition, these patients may not be able to articulate their symptoms as clearly as an adult patient, further stressing the importance of obtaining a pertinent history and performing a focused physical examination. Having a thorough understanding of the anatomy, the varying pathologies, and the indications for surgical and nonsurgical management will assist in improved patient outcomes.

Triangular Fibrocartilage Complex Injuries in Children and Adolescents

Triangular fibrocartilage complex (TFCC) tears can cause ulnar-sided wrist pain in children and adolescents following acute rotational injury or prior distal radius fracture. Surgical treatment, guided by the Palmer classification, is considered after activity modification and occupational therapy. All concomitant wrist pathologies, such as distal radioulnar joint instability, ulnocarpal impaction, and distal radius malunion, must be recognized and addressed at the time of TFCC debridement or repair. This article reviews recent literature guiding clinical evaluation and surgical treatment of children and adolescents with TFCC injuries. The authors' techniques for arthroscopic-assisted outside-in repair of Palmer 1B and 1D tears are described.

The clinical significance of magnetic resonance imaging of the hand: an analysis of 318 hand and wrist images referred by hand surgeons

Magnetic resonance imaging (MRI) is a common diagnostic tool in hand surgery. However, there is limited knowledge on the kind of findings that are relevant in treatment planning. We analysed the findings and utility of arm, wrist, metacarpal, and finger MRIs taken in a tertiary hand surgery clinic of 318 consecutive images from 316 patients referred by a hand surgeon or hand surgeon resident. Ganglions (28%), findings on the extensor carpi ulnaris tendon (18%) and on the triangular fibrocartilage (18%) were the most common findings and increased with patient age; the clinical significance of these findings was minimal. The correlation between the clinical scaphoid shift test or the fovea sign test and MRI was also non-significant. Despite findings on MRI, the diagnosis remained unsolved in 76 (24%) cases. However, MRI had a role in reassuring the patient, and in 70% of the cases, further follow-up was unnecessary. This study demonstrates that the indications for wrist and hand MRI must be considered thoroughly and interpretation of the MRI report requires knowledge.

MRI Utility in Hand Surgery

Background: Magnetic resonance imaging (MRI) is frequently used in the diagnosis of upper extremity conditions. We hypothesize that the results often do not change treatment. The purpose of the present study was to prospectively assess the extent to which MRI findings alter patient management. Methods: Ten hand surgeons who were ordering an MRI (elbow or distal) completed a standardized questionnaire. Prior to obtaining the MRI, the surgeon recorded their pre-MRI diagnosis and recommended treatment if no MRI could be obtained. Following the MRI, the surgeon recorded their post-MRI diagnosis and ultimate treatment recommendation. Finally, the surgeon answered whether the MRI was helpful, and if so, how it helped guide their treatment. Descriptive statistics were performed. Results: One hundred eighty-seven MRIs were ordered. The most common reasons for ordering an MRI were the evaluation of presumed occult scaphoid fracture, ulnar wrist pain, metacarpophalangeal joint collateral ligament injury, and mass. The surgeon agreed with the radiologist's interpretation of the MRI in 88% of cases. Overall, surgeons found the MRI to be helpful in 92% of cases, and the recommended treatment changed as a result of the MRI findings in 19% (35/187) of patients. Of these 35 patients, 9 had a pre-MRI diagnosis that was concordant with the MRI findings, but the proposed management of the patient changed after the MRI. Conclusions: Hand surgeons infrequently change their treatment plan based on MRI findings. Given the importance of cost-efficient care, indications for use of MRI may need to be re-evaluated.

Review article: the differential diagnosis of bone marrow edema on wrist MRI

There is a large variety of conditions that can result in 'bone marrow edema' or 'bone marrow lesions' (BML) in the wrist on magnetic resonance imaging (MRI). The combination of clinical history and the distribution of the BML can serve as a valuable clue to a specific diagnosis. This article illustrates the different patterns of BML in the wrist to serve as a useful guide when reviewing wrist MRI studies. Imaging artefacts will also be briefly covered.