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MRI findings in regional migratory osteoporosis of the knee migrating from the femur to the tibia
Clinical Imaging 30 (2006) 428 – 430
MRI findings in regional migratory osteoporosis of the knee migrating from the femur to the tibia Fabio Minutoli, Michele Gaeta, Antonio Bottari4, Alfredo Blandino Department of Radiological Sciences, University of Messina, Viale Gazzi, 98122 Messina, Italy Received 15 April 2006; accepted 31 May 2006
Abstract Regional migratory osteoporosis (RMO) is an uncommon self-limiting disease characterized by migrating bone marrow edema and osteoporosis. RMO of the knee with intra-articular migration is very rare. In such cases, different parts of the femur are usually involved. We report a case of intra-articular RMO of the knee migrating from the femur to the tibia—a pattern of migration that has not been previously described in the literature. D 2006 Elsevier Inc. All rights reserved. Keywords: Regional migratory osteoporosis; RMO; Bone marrow edema; Magnetic resonance imaging
1. Introduction Regional migratory osteoporosis (RMO) is an uncommon self-limiting disease characterized by migrating arthralgia involving the weight-bearing joints of the lower limbs, appearing on imaging as migrating bone marrow edema associated with osteoporosis. Different patterns of bone marrow edema migration have been described. Intra-articular migration pattern is very rare; furthermore, in cases of RMO of the knee with intraarticular migration, different parts of the femur are usually involved [1]. We describe a case of intra-articular RMO of the knee migrating from the femur to the tibia—a pattern of migration that has not been specifically addressed in the English literature. 2. Case report A 49-year-old man presented with a 2-week history of pain on the left knee. 4 Corresponding author. Via Cons. Pompea 84 (Sant’ Agata), 98166 Messina, Italy. E-mail address: [email protected] (A. Bottari). 0899-7071/06/$ – see front matter D 2006 Elsevier Inc. All rights reserved. doi:10.1016/j.clinimag.2006.05.032
There was neither a history of trauma nor risk factors for osteonecrosis. Sedimentation rate, white blood cells count, and alkaline phosphatase level revealed normal results. Radiographs showed no abnormalities. The patient underwent magnetic resonance (MR) examination that showed a large ill-defined area of increased signal intensity on fat-saturated T2-weighted images consistent with bone marrow edema involving the lateral femoral condyle of the left knee. There were adjacent soft tissue edema and mild joint effusion (Fig. 1). Despite nonweight-bearing therapy, the patient complained of continued pain 3 months later. A new MR examination revealed partial resolution of bone marrow edema in the lateral femoral condyle and the appearance of bone marrow edema in the contralateral femoral condyle (Fig. 2). Radiographs showed moderate osteopenia. Because of continued pain, the patient underwent magnetic resonance imaging (MRI) 3 months later, which showed complete resolution of the bone marrow edema of the lateral femoral condyle, increase of bone marrow edema extension into the contralateral femoral condyle, and appearance of bone marrow edema involving both tibial plateaus (Fig. 3). The patient continued conservative therapy, and symptoms resolved approximately 11 months later.
F. Minutoli et al. / Clinical Imaging 30 (2006) 428 – 430
429
Fig. 1. Coronal T2-weighted fat-saturated fast spin-echo image of the knee showing bone marrow edema of the lateral femoral condyle (arrow). Note the edema of adjacent soft tissues (black arrowheads) and scant joint effusion (white arrowheads).
The MRI also demonstrated complete resolution of bone marrow edema.
3. Discussion RMO, which was first described by Duncan et al. [2], is an uncommon often mislabeled disease with an uncertain etiology. It is a temporal sequential polyarticular arthralgia of weight-bearing joints that is associated with bone marrow edema and local regional osteoporosis or, occasionally,
Fig. 3. (A and B) Coronal T2-weighted fat-saturated fast spin-echo images of the knee obtained 3 months later (cf. Fig. 2) show resolution of the bone marrow edema of the lateral femoral condyle, increase of bone marrow edema in the medial femoral condyle, and the appearance of bone marrow edema involving both tibial plateaus. Soft tissue edema and mild joint effusion are still present.
Fig. 2. Coronal T2-weighted fat-saturated fast spin-echo image of the knee obtained 3 months later (cf. Fig. 1) shows partial resolution of bone marrow edema in the lateral femoral condyle and the appearance of bone marrow edema in the medial femoral condyle. In addition, soft tissue edema is diminished on the lateral aspect of the knee and is increased on the medial side. Mild joint effusion is still appreciable.
widespread osteoporosis that is most frequently described in the lower appendicular skeleton [1]. Clinically, RMO presents with monoarticular arthralgia (not related to trauma) that moves from one joint to another. MRI shows bone marrow edema (decreased signal intensity of the affected bone marrow on T1-weighted images and increased signal intensity on T2-weighted images, particularly on T2-weighted fat-saturated Fast Spin Echo or short tau inversion recovery images) at symptomatic sites,
430
F. Minutoli et al. / Clinical Imaging 30 (2006) 428 – 430
and plain radiography demonstrates local osseous demineralization. Bone scintigraphy reveals increased bone radionuclide uptake. Therapy is conservative, since oral analgesia and nonweight-bearing strategies usually evolve to pain relief and complete resolution. Different patterns of joint involvement exist in RMO. The most common pattern is represented by the ipsilateral joint involvement of the hip, knee, and ankle; most commonly, arthralgia starts proximally in the hip and migrates distally to the ankle. Intra-articular migration, recurrent episodes affecting the same joint, and multiple bone involvement of the ipsilateral foot and ankle are three other possible, but rarer, patterns [1]. Intra-articular RMO of the knee is very rare; it has been reported only a few times [3–6]. Femoral condyles are the most commonly involved sites. In all reported cases, indeed, a femoral condyle was initially involved with a shift of the bone marrow edema of the contralateral femoral condyle. Condylar migration seems not to be due to a compensatory mechanism by the patient who shifts weight bearing to the nonedematous contralateral condyle because bone marrow edema in volunteers with altered weight bearing has been demonstrated to be less extensive than that in patients with RMO [7]. RMO diagnosis is important because it may simulate more aggressive diseases such as neoplasms, osteomyelitis, or avascular necrosis. Demonstration of osteoporosis and the shifting of bone marrow edema on follow-up examinations suggest a
diagnosis of RMO. RMO differs from transient bone marrow edema syndrome due to evidence of radiographic osteopenia, and both these entities can be distinguished from osteonecrosis by the lack of demarcation of the area of bone marrow edema [8]. Knowledge of the migration patterns of RMO, including the shifting of bone marrow edema from one bone to another within the same articulation, can permit a more confident diagnosis of this benign self-limiting condition, obviating aggressive management.
References [1] Toms AP, Marshall TJ, Becker E, Donell ST, Lobo-Mueller EM, Barker T. Regional migratory osteoporosis: a review illustrated by five cases. Clin Radiol 2005;60:425 – 38. [2] Duncan H, Frame B, Frost H, Arnstein AR. Regional migratory osteoporosis. South Med J 1969;62:41 – 4. [3] Moosikasuwan JB, Miller TT, Math K, Schultz E. Shifting bone marrow edema of the knee. Skeletal Radiol 2004;33:380 – 5. [4] Parker RK, Ross GJ, Urso JA. Transient osteoporosis of the knee. Skeletal Radiol 1997;26:306 – 9. [5] Wambeek N, Munk PL, Lee MJ, Meek RN. Intra-articular regional migratory osteoporosis of the knee. Skeletal Radiol 2000;29:97 – 100. [6] Fertakos RJ, Swayne LC, Colston WC. Three phase bone imaging in bone marrow edema of the knee. Clin Nucl Med 1995;20:587 – 90. [7] Schweitzer ME, White LM. Does altered biomechanics cause marrow edema? Radiology 1996;198:851 – 3. [8] Gaeta M, Mazziotti S, Minutoli F, Vinci S, Blandino A. Migrating transient bone marrow edema syndrome of the knee: MRI findings in a new case. Eur Radiol 2002;12:S40 – 2.
MRI findings in regional migratory osteoporosis of the knee migrating from the femur to the tibia Fabio Minutoli, Michele Gaeta, Antonio Bottari4, Alfredo Blandino Department of Radiological Sciences, University of Messina, Viale Gazzi, 98122 Messina, Italy Received 15 April 2006; accepted 31 May 2006
Abstract Regional migratory osteoporosis (RMO) is an uncommon self-limiting disease characterized by migrating bone marrow edema and osteoporosis. RMO of the knee with intra-articular migration is very rare. In such cases, different parts of the femur are usually involved. We report a case of intra-articular RMO of the knee migrating from the femur to the tibia—a pattern of migration that has not been previously described in the literature. D 2006 Elsevier Inc. All rights reserved. Keywords: Regional migratory osteoporosis; RMO; Bone marrow edema; Magnetic resonance imaging
1. Introduction Regional migratory osteoporosis (RMO) is an uncommon self-limiting disease characterized by migrating arthralgia involving the weight-bearing joints of the lower limbs, appearing on imaging as migrating bone marrow edema associated with osteoporosis. Different patterns of bone marrow edema migration have been described. Intra-articular migration pattern is very rare; furthermore, in cases of RMO of the knee with intraarticular migration, different parts of the femur are usually involved [1]. We describe a case of intra-articular RMO of the knee migrating from the femur to the tibia—a pattern of migration that has not been specifically addressed in the English literature. 2. Case report A 49-year-old man presented with a 2-week history of pain on the left knee. 4 Corresponding author. Via Cons. Pompea 84 (Sant’ Agata), 98166 Messina, Italy. E-mail address: [email protected] (A. Bottari). 0899-7071/06/$ – see front matter D 2006 Elsevier Inc. All rights reserved. doi:10.1016/j.clinimag.2006.05.032
There was neither a history of trauma nor risk factors for osteonecrosis. Sedimentation rate, white blood cells count, and alkaline phosphatase level revealed normal results. Radiographs showed no abnormalities. The patient underwent magnetic resonance (MR) examination that showed a large ill-defined area of increased signal intensity on fat-saturated T2-weighted images consistent with bone marrow edema involving the lateral femoral condyle of the left knee. There were adjacent soft tissue edema and mild joint effusion (Fig. 1). Despite nonweight-bearing therapy, the patient complained of continued pain 3 months later. A new MR examination revealed partial resolution of bone marrow edema in the lateral femoral condyle and the appearance of bone marrow edema in the contralateral femoral condyle (Fig. 2). Radiographs showed moderate osteopenia. Because of continued pain, the patient underwent magnetic resonance imaging (MRI) 3 months later, which showed complete resolution of the bone marrow edema of the lateral femoral condyle, increase of bone marrow edema extension into the contralateral femoral condyle, and appearance of bone marrow edema involving both tibial plateaus (Fig. 3). The patient continued conservative therapy, and symptoms resolved approximately 11 months later.
F. Minutoli et al. / Clinical Imaging 30 (2006) 428 – 430
429
Fig. 1. Coronal T2-weighted fat-saturated fast spin-echo image of the knee showing bone marrow edema of the lateral femoral condyle (arrow). Note the edema of adjacent soft tissues (black arrowheads) and scant joint effusion (white arrowheads).
The MRI also demonstrated complete resolution of bone marrow edema.
3. Discussion RMO, which was first described by Duncan et al. [2], is an uncommon often mislabeled disease with an uncertain etiology. It is a temporal sequential polyarticular arthralgia of weight-bearing joints that is associated with bone marrow edema and local regional osteoporosis or, occasionally,
Fig. 3. (A and B) Coronal T2-weighted fat-saturated fast spin-echo images of the knee obtained 3 months later (cf. Fig. 2) show resolution of the bone marrow edema of the lateral femoral condyle, increase of bone marrow edema in the medial femoral condyle, and the appearance of bone marrow edema involving both tibial plateaus. Soft tissue edema and mild joint effusion are still present.
Fig. 2. Coronal T2-weighted fat-saturated fast spin-echo image of the knee obtained 3 months later (cf. Fig. 1) shows partial resolution of bone marrow edema in the lateral femoral condyle and the appearance of bone marrow edema in the medial femoral condyle. In addition, soft tissue edema is diminished on the lateral aspect of the knee and is increased on the medial side. Mild joint effusion is still appreciable.
widespread osteoporosis that is most frequently described in the lower appendicular skeleton [1]. Clinically, RMO presents with monoarticular arthralgia (not related to trauma) that moves from one joint to another. MRI shows bone marrow edema (decreased signal intensity of the affected bone marrow on T1-weighted images and increased signal intensity on T2-weighted images, particularly on T2-weighted fat-saturated Fast Spin Echo or short tau inversion recovery images) at symptomatic sites,
430
F. Minutoli et al. / Clinical Imaging 30 (2006) 428 – 430
and plain radiography demonstrates local osseous demineralization. Bone scintigraphy reveals increased bone radionuclide uptake. Therapy is conservative, since oral analgesia and nonweight-bearing strategies usually evolve to pain relief and complete resolution. Different patterns of joint involvement exist in RMO. The most common pattern is represented by the ipsilateral joint involvement of the hip, knee, and ankle; most commonly, arthralgia starts proximally in the hip and migrates distally to the ankle. Intra-articular migration, recurrent episodes affecting the same joint, and multiple bone involvement of the ipsilateral foot and ankle are three other possible, but rarer, patterns [1]. Intra-articular RMO of the knee is very rare; it has been reported only a few times [3–6]. Femoral condyles are the most commonly involved sites. In all reported cases, indeed, a femoral condyle was initially involved with a shift of the bone marrow edema of the contralateral femoral condyle. Condylar migration seems not to be due to a compensatory mechanism by the patient who shifts weight bearing to the nonedematous contralateral condyle because bone marrow edema in volunteers with altered weight bearing has been demonstrated to be less extensive than that in patients with RMO [7]. RMO diagnosis is important because it may simulate more aggressive diseases such as neoplasms, osteomyelitis, or avascular necrosis. Demonstration of osteoporosis and the shifting of bone marrow edema on follow-up examinations suggest a
diagnosis of RMO. RMO differs from transient bone marrow edema syndrome due to evidence of radiographic osteopenia, and both these entities can be distinguished from osteonecrosis by the lack of demarcation of the area of bone marrow edema [8]. Knowledge of the migration patterns of RMO, including the shifting of bone marrow edema from one bone to another within the same articulation, can permit a more confident diagnosis of this benign self-limiting condition, obviating aggressive management.
References [1] Toms AP, Marshall TJ, Becker E, Donell ST, Lobo-Mueller EM, Barker T. Regional migratory osteoporosis: a review illustrated by five cases. Clin Radiol 2005;60:425 – 38. [2] Duncan H, Frame B, Frost H, Arnstein AR. Regional migratory osteoporosis. South Med J 1969;62:41 – 4. [3] Moosikasuwan JB, Miller TT, Math K, Schultz E. Shifting bone marrow edema of the knee. Skeletal Radiol 2004;33:380 – 5. [4] Parker RK, Ross GJ, Urso JA. Transient osteoporosis of the knee. Skeletal Radiol 1997;26:306 – 9. [5] Wambeek N, Munk PL, Lee MJ, Meek RN. Intra-articular regional migratory osteoporosis of the knee. Skeletal Radiol 2000;29:97 – 100. [6] Fertakos RJ, Swayne LC, Colston WC. Three phase bone imaging in bone marrow edema of the knee. Clin Nucl Med 1995;20:587 – 90. [7] Schweitzer ME, White LM. Does altered biomechanics cause marrow edema? Radiology 1996;198:851 – 3. [8] Gaeta M, Mazziotti S, Minutoli F, Vinci S, Blandino A. Migrating transient bone marrow edema syndrome of the knee: MRI findings in a new case. Eur Radiol 2002;12:S40 – 2.