Detection of occult wrist fractures by quantitative radioscintigraphy: a prospective study on selected patients.

OBJECTIVE: To determine the value of quantitative radioscintigraphy (QRS) in the diagnosis of wrist trauma occult fractures.

PURPOSE: Because of the risk of non-union, the diagnosis of wrist fractures, including scaphoid fractures, is essential but remains difficult despite many imaging modalities. The aim of the study was to assess the benefits of QRS in the diagnosis of occult post-trauma wrist fractures.

METHODS: This prospective study included all patients presenting at the orthopaedic department at Brest University Hospital for wrist pain after trauma with initial normal plain radiographs. Patients with normal radiographs but strongly suspected of fracture underwent QRS consisting of three-phase bone scintigraphy with quantitative analysis. When a fracture was suspected the radiograph and scintigraphy were fused to precisely locate the fracture if the index was higher than 2. If the index was lower than 1.9, fracture was excluded. Between these two indices, other investigations, such as magnetic resonance imaging, were performed. All patients were followed for at least 3 months and reviewed by the same surgeon. Patients underwent a physical examination and possibly other investigations.

RESULTS: From April 2006 to July 2008, 87 patients were enrolled (34 women, 53 men; median age 29 years; range, 15-87 years). Among the 46 pathologic bone scintigrams, 55 occult fractures were highlighted. At follow-up, none presented non-union. One had an undetermined QRS. Among the 40 negative results for QRS at follow-up, only one had a non-union. Sensitivity and negative predictive value were 97 and 98%, respectively for carpal fractures.

CONCLUSION: This study highlights the benefit of QRS, which allows the detection of most occult carpal fractures and reduces the risks of complications such as pseudoarthritis.