Wrist injuries in young adults: The diagnostic impact of CT and MRI

Abstract

Purpose

To evaluate the diagnostic impact of MRI or/and multidetector CT in young patients with wrist injury and inconclusive or negative clinical examination and X-rays and to analyze variations in imaging strategies between a district general hospital (GH) and a university hospital (UH).

Materials and methods

A retrospective analysis of 34 young patients (mean age 23 years) with wrist trauma who underwent CT or/and MRI was performed. The injury was acute in 24, and chronic in 10 patients. Twenty-two patients were from a GH and 12 from a UH. Two experienced musculoskeletal radiologists blindly reviewed the imaging studies. The effect of cross-sectional imaging on patient care and treatment plan was evaluated.

Results

In 9 of 34 patients one or more fractures were diagnosed on cross-sectional imaging. The scaphoid was fractured in four patients, the lunate and/or the trapezium in three patients, the scaphoid together with the lunate in one patient, and finally the distal radius in one patient. Ligamentous trauma was identified solely on MRI in 11 patients (involving the TFCC in eight cases). In four patients with both imaging methods, CT revealed one fracture of the trapezium not seen on MRI, and one scapholunate fracture with MRI findings of distal radial fracture only. In two patients with normal CT, MRI revealed bone marrow oedema of the scaphoid in one and of the distal radius, lunate and triquetrum in the other.

Conclusion

Both CT and MRI might be considered in patients with acute or chronic wrist injury, clinical dilemma and normal initial radiographs, depending on the availability and the individual institution policies.

Introduction

The evaluation of patients with wrist injuries is a diagnostic challenge. In many cases the clinical examination does not provide diagnostic certainty and radiographs traditionally used in the initial investigation might be negative as some fractures are often occult on X-rays. Therefore missed diagnoses of fracture or ligamentous injury are not uncommon and may lead to inadequate treatment and complications [1]. For further diagnostic investigation, magnetic resonance imaging (MRI) and/or multidetector computed tomography (CT) might be considered depending on the availability and the policy in radiological departments [2]. Significant differences to patient management have already been shown to result from the information conducted by cross-sectional imaging. Many institutions consider CT as the second step of imaging wrist trauma, regardless of access to MRI. CT has been shown to be superior to MRI for the detection of occult cortical scaphoid fractures and inferior to MRI for identifying trabecular bone and ligamentous injury [3]. Others prefer MRI, particularly if the clinical diagnosis is focused on occult scaphoid fractures [4]. The availability of dedicated MR scanners in the emergency departments, with their inherent easy performance, has contributed to such an approach [5], [6], [7].

Despite differences in strategies, it is crucial that the treating physician is aware of the exact injury pattern, especially in cases with a high index of clinical suspicion [8]. To the best of our knowledge, there is controversy in the literature for the cross-sectional investigation of choice in patients with wrist injury. There seems to be no sufficient evidence on an established or generally accepted diagnostic imaging algorithm, for the assessment of wrist pathology following trauma in a well-documented clinical scenario [9].

In a literature search, we did not find many reports making a definitive statement about the value of both CT and MRI for the assessment of the post-traumatic wrist. Given the fact that the wrist is an anatomically complex area, the clinicians might place great value on the imaging method that would refine the diagnosis, especially in the emergency department setting [10]. In addition, it is admittedly even more substantial to provide a young patient with wrist trauma a clear diagnosis and reassurance about the further care plan. In this context we sought to assess the effect of CT and MRI on diagnostic certainty in young patients with a strong clinical suspicion and negative radiographs (initial and follow-up). The study was designed to evaluate the link between the cross-sectional imaging findings and the alteration of management and to highlight the differences of the diagnostic process in a university hospital (UH) and a district general hospital (GH) in two European countries, respectively.