In addition to its increased sensitivity for fracture detection, MRI has been shown to be useful in characterizing fracture morphology. Seemingly isolated fractures of the greater trochanter diagnosed on radiography frequently have intertrochanteric extension when evaluated with MRI [22]. In a classic study of 30 patients, Schultz et al [40] demonstrated the use of MRI to accurately depict the extent of the fracture line in these radiographically occult intertrochanteric fractures. There is an increasing trend to treat incomplete intertrochanteric fractures conservatively. For example, in a small series of 8 patients, Alam et al [41] found that of the 5 patients treated conservatively, none went on to complete their fracture. Several authors have suggested that with its ability to depict fracture morphology with accuracy, MRI may have a continued role to play in directing treatment [22,40]. Specific scanning protocols have emphasized either speed or comprehensiveness. A 2003 study of 93 cases found 100% sensitivity for the coronal short tau inversion-recovery (STIR) sequence alone [42], and a more recent study found 99% sensitivity of the coronal STIR sequence with increasing confidence and specificity with the addition of a coronal T1 sequence [43]. Given the increasing throughput pressures in the emergency department and the Acute Hip Pain-Suspected Fracture difficulty of older patients in tolerating long scan times, there continues to be interest in developing rapid and accurate MRI protocols. With the diagnostic accuracy of noncontrast MRI approaching 100%, there has been little need to explore the addition of IV gadolinium contrast solely for the purposes of fracture detection. Rather, the interest has been in the use of dynamic MRI to evaluate femoral head perfusion for prognostic purpose to estimate the risks of impaired perfusion, such as osteonecrosis and nonunion.
Acute Hip Pain Suspected Fracture PCAs. In addition to its increased sensitivity for fracture detection, MRI has been shown to be useful in characterizing fracture morphology. Seemingly isolated fractures of the greater trochanter diagnosed on radiography frequently have intertrochanteric extension when evaluated with MRI [22]. In a classic study of 30 patients, Schultz et al [40] demonstrated the use of MRI to accurately depict the extent of the fracture line in these radiographically occult intertrochanteric fractures. There is an increasing trend to treat incomplete intertrochanteric fractures conservatively. For example, in a small series of 8 patients, Alam et al [41] found that of the 5 patients treated conservatively, none went on to complete their fracture. Several authors have suggested that with its ability to depict fracture morphology with accuracy, MRI may have a continued role to play in directing treatment [22,40]. Specific scanning protocols have emphasized either speed or comprehensiveness. A 2003 study of 93 cases found 100% sensitivity for the coronal short tau inversion-recovery (STIR) sequence alone [42], and a more recent study found 99% sensitivity of the coronal STIR sequence with increasing confidence and specificity with the addition of a coronal T1 sequence [43]. Given the increasing throughput pressures in the emergency department and the Acute Hip Pain-Suspected Fracture difficulty of older patients in tolerating long scan times, there continues to be interest in developing rapid and accurate MRI protocols. With the diagnostic accuracy of noncontrast MRI approaching 100%, there has been little need to explore the addition of IV gadolinium contrast solely for the purposes of fracture detection. Rather, the interest has been in the use of dynamic MRI to evaluate femoral head perfusion for prognostic purpose to estimate the risks of impaired perfusion, such as osteonecrosis and nonunion.