Bone scintigraphy for osteonecrosis of the knee in patients with non-traumatic osteonecrosis of the femoral head: comparison with magnetic resonance imaging

Abstract

Objective-To determine whether technetium bone scintigraphy (BS) is useful for screening of non-traumatic osteonecrosis of the knee (ONK), which was a major aVected site, secondary to the femoral head, among multiple osteonecrosis, in patients with non-traumatic osteonecrosis of the femoral head (ONFH). Methods-A total of 214 knee joints in 107 patients with ONFH were evaluated by BS and a comparison made with magnetic resonance imaging (MRI). ONK was classified into five sites, including the femoral condyles (ONFC), distal femoral metaphysis (ONFM), tibial plateau (ONTP), proximal tibial metaphysis (ONTM), and patella (ONP).Results-Based on the diagnosis by MRI, ONK was detected in 103 knees of 62 patients (48%). ONFC was most common (86 knees, 40%), ONFM (15%), followed by ONTM (10%), ONP (3%), and ONTP (0.9%). Sensitivity, specificity, and accuracy of BS for ONFC detection were 63%, 71%, and 68%, respectively. When the ONFC lesions on the coronal views of MRI were large or medium sized and occupied two thirds, or the entire anteroposterior joint surface on the sagittal views, the sensitivity of BS for ONFC detection increased to 89% (34/38 knees). The sensitivity of BS for ONFM, ONTM, and ONP detection was 3%, 0%, and 0%, respectively, but these lesions showed a low likelihood of collapse. Conclusion-BS is useful for screening large ONK in patients with ONFH given that 89% of patients with ONFC who had a high risk of collapse of the knee were identified.

Spontaneous Regression of Steroid-related Osteonecrosis of the Knee

“…The presence of a necrotic lesion was confirmed by a normal fat intensity area surrounded by a low-intensity band on T1-weighted MR images. 21,24,25 We excluded 15 patients (29 knees) who were lost to followup, three patients (six knees) who had the initial MRI performed with different imaging protocols, 14 patients (26 knees) who did not agree to have a second MRI, and two patients (four knees) who died. Therefore, 17 patients (30 knees) of the 51 diagnosed with ON of the knee (33%) were included.…”

“…1,2,12,19,22,24,25,28 Osteonecrosis of the knee may appear spontaneously in patients without known risk factors or may be related to steroid or alcohol use or associated with numerous well-recognized predisposing factors such as connective tissue disease, organ transplantation, corticosteroid use, and alcoholism. 4,14,16,17 Although spontaneous ON of the knee has been described, 1,2,5,15,18,28 there have been few reports of steroidrelated or alcohol-related ON of the knee.…”

“…21,23,24 It also is useful to monitor changes in the lesion, but leg rotation and knee flexion are not always uniform at each imaging session. An accurate evaluation of a change in lesion size requires precise matching of the rotation and level of MRI.…”

“…4,14,16,17 Although spontaneous ON of the knee has been described, 1,2,5,15,18,28 there have been few reports of steroidrelated or alcohol-related ON of the knee. 19,24,25,27 Most patients with steroid or alcohol-related ON are continuously exposed to risk even after the onset of ON. 9,30 Consequently, repeated ischemia and a subsequent increase in the size of the necrotic lesion may occur.…”

Bone Scintigraphy Scanning Safety and Necessity for Silent and Multifocal Osteonecrosis in Sickle Cell Disease

“…Nuclear imaging indicates regions of increased metabolic activity (hot spots) by an increased uptake of a radioactive tracer. It is useful in detecting bone metastatic disease, osteomyelitis, osteonecrosis, arthritis, and Paget's disease [23]. BSc can examine multiple bones and joints lesions at one time on total body imaging to determining whether multiple osteonecrosis develops in other parts in the body [24].…”