DOI: 10.1148/rg.263055091
MR Imaging of Temporomandibular Joint Dysfunction: A Pictorial Review1
Xavier Tomas, MD,
Jaume Pomes, MD,
Juan Berenguer, MD,
Llorenç Quinto, MD,
Carlos Nicolau, MD,
Josep Maria Mercader, MD and
Vicente Castro, MD
1 From the Department of Radiology (X.T., J.P., J.B., C.N., J.M.M.), the Department of Epidemiology and Biostatistics, the Institut d’Investigació Biomèdica August Pi i Sunyer (L.Q.), and the Department of Oral and Maxillofacial Surgery (V.C.), Hospital Clínic, Facultat de Medicina, Universitat de Barcelona, Villarroel 170, Barcelona 08036, Spain. Presented as an education exhibit at the 2004 RSNA Annual Meeting. Received April 11, 2005; revision requested June 13 and received July 18; accepted August 10. All authors have no financial relationships to disclose.
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Figure 1. Drawing illustrates the anatomy of the TMJ. 1 = condyle; 2 = temporal bone, articular eminence; 3 = temporal bone, mandibular fossa; 4 = disk, anterior band; 5 = disk, intermediate zone; 6 = disk, posterior band; 7 = superior retrodiskal layer; 8 = inferior retrodiskal layer; 9 = vasculonervous structures; 10 = capsular superior attachment; 11 = capsular inferior attachment; 12 = superior joint space; 13 = inferior joint space; 14 = superior head of the lateral pterygoid muscle (LPM); 15 = inferior head of the LPM; 16 = interpterygoid space; 17 = external auditory canal.
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Figure 2. Sagittal oblique spin-echo T1-weighted magnetic resonance (MR) image obtained in the closed-mouth position shows the normal TMJ. (Reprinted, with permission, from reference 1.)
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Figure 3a. Drawings illustrate TMJ function. (a) Initial closed-mouth position. (b) At the beginning of the open-mouth position, the digastric muscle forces the condyle downward. The condyle then rotates in the lower joint space, and condylar displacement begins when the jaw is opened beyond 20–25 mm. Retrodiskal ligaments stabilize the disk. (c) Condylar protraction (maximum open-mouth position). Involvement of the inferior LPM is basic to this step, and the superior LPM can displace the disk, probably to maintain joint congruence. The superior retrodiskal layer prevents complete abnormal displacement. (d) Progression to the maximum clenching position. The inferior LPM is normally very active in this phase as well.
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Figure 3b. Drawings illustrate TMJ function. (a) Initial closed-mouth position. (b) At the beginning of the open-mouth position, the digastric muscle forces the condyle downward. The condyle then rotates in the lower joint space, and condylar displacement begins when the jaw is opened beyond 20–25 mm. Retrodiskal ligaments stabilize the disk. (c) Condylar protraction (maximum open-mouth position). Involvement of the inferior LPM is basic to this step, and the superior LPM can displace the disk, probably to maintain joint congruence. The superior retrodiskal layer prevents complete abnormal displacement. (d) Progression to the maximum clenching position. The inferior LPM is normally very active in this phase as well.
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Figure 3c. Drawings illustrate TMJ function. (a) Initial closed-mouth position. (b) At the beginning of the open-mouth position, the digastric muscle forces the condyle downward. The condyle then rotates in the lower joint space, and condylar displacement begins when the jaw is opened beyond 20–25 mm. Retrodiskal ligaments stabilize the disk. (c) Condylar protraction (maximum open-mouth position). Involvement of the inferior LPM is basic to this step, and the superior LPM can displace the disk, probably to maintain joint congruence. The superior retrodiskal layer prevents complete abnormal displacement. (d) Progression to the maximum clenching position. The inferior LPM is normally very active in this phase as well.
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Figure 3d. Drawings illustrate TMJ function. (a) Initial closed-mouth position. (b) At the beginning of the open-mouth position, the digastric muscle forces the condyle downward. The condyle then rotates in the lower joint space, and condylar displacement begins when the jaw is opened beyond 20–25 mm. Retrodiskal ligaments stabilize the disk. (c) Condylar protraction (maximum open-mouth position). Involvement of the inferior LPM is basic to this step, and the superior LPM can displace the disk, probably to maintain joint congruence. The superior retrodiskal layer prevents complete abnormal displacement. (d) Progression to the maximum clenching position. The inferior LPM is normally very active in this phase as well.
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Figure 4a. Morphologic features of the normal disk. (a) On a sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position), the anterior and posterior bands are thick and the intermediate zone (arrow) is thin, creating a biconcave disk shape. (b) Sagittal oblique gradient-echo T2-weighted MR image (open-mouth position) more clearly depicts the posterior band and retrodiskal tissue (arrow). These anatomic entities are best depicted in the open-mouth position.
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Figure 4b. Morphologic features of the normal disk. (a) On a sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position), the anterior and posterior bands are thick and the intermediate zone (arrow) is thin, creating a biconcave disk shape. (b) Sagittal oblique gradient-echo T2-weighted MR image (open-mouth position) more clearly depicts the posterior band and retrodiskal tissue (arrow). These anatomic entities are best depicted in the open-mouth position.
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Figure 5a. Drawings (sagittal oblique views) illustrate disk displacement in the closed-mouth position. (a) A pathologic condition is considered to be present if the angle between the posterior band and the vertical orientation of the condyle (twelve o’clock position) exceeds 10°. (b) Rammelsberg et al (19) recommended that anterior disk displacement of up to 30° be considered normal to better correlate disk displacement with clinical symptoms of TMJ dysfunction.
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Figure 5b. Drawings (sagittal oblique views) illustrate disk displacement in the closed-mouth position. (a) A pathologic condition is considered to be present if the angle between the posterior band and the vertical orientation of the condyle (twelve o’clock position) exceeds 10°. (b) Rammelsberg et al (19) recommended that anterior disk displacement of up to 30° be considered normal to better correlate disk displacement with clinical symptoms of TMJ dysfunction.
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Figure 6a. Abnormal morphologic features of the disk. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows a displaced disk (arrow) that has lost its typical biconcavity, having become crumpled and irregular. (Reprinted, with permission, from reference 1.) (b) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) obtained in a different patient shows a pathologic displaced disk with a rounded shape (arrow). (c) Sagittal oblique spin-echo proton-density–weighted MR image (closed-mouth position) obtained in a third patient shows a flattened displaced disk (arrow). (d) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) obtained in a fourth patient demonstrates perforation of the intermediate zone of the disk (arrow).
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Figure 6b. Abnormal morphologic features of the disk. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows a displaced disk (arrow) that has lost its typical biconcavity, having become crumpled and irregular. (Reprinted, with permission, from reference 1.) (b) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) obtained in a different patient shows a pathologic displaced disk with a rounded shape (arrow). (c) Sagittal oblique spin-echo proton-density–weighted MR image (closed-mouth position) obtained in a third patient shows a flattened displaced disk (arrow). (d) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) obtained in a fourth patient demonstrates perforation of the intermediate zone of the disk (arrow).
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Figure 6c. Abnormal morphologic features of the disk. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows a displaced disk (arrow) that has lost its typical biconcavity, having become crumpled and irregular. (Reprinted, with permission, from reference 1.) (b) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) obtained in a different patient shows a pathologic displaced disk with a rounded shape (arrow). (c) Sagittal oblique spin-echo proton-density–weighted MR image (closed-mouth position) obtained in a third patient shows a flattened displaced disk (arrow). (d) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) obtained in a fourth patient demonstrates perforation of the intermediate zone of the disk (arrow).
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Figure 6d. Abnormal morphologic features of the disk. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows a displaced disk (arrow) that has lost its typical biconcavity, having become crumpled and irregular. (Reprinted, with permission, from reference 1.) (b) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) obtained in a different patient shows a pathologic displaced disk with a rounded shape (arrow). (c) Sagittal oblique spin-echo proton-density–weighted MR image (closed-mouth position) obtained in a third patient shows a flattened displaced disk (arrow). (d) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) obtained in a fourth patient demonstrates perforation of the intermediate zone of the disk (arrow).
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Figure 7a. Abnormal disk displacement in TMJ dysfunction. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows significant disk displacement. The intermediate zone is clearly beyond the condyle, and the angle between the posterior band (dashed line) and vertical (solid line) is close to 50°. (b) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) obtained in a different patient clearly depicts anteromedial disk displacement. The disk (arrow) appears to be "floating" by itself, and the condyle is no longer visualized.
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Figure 7b. Abnormal disk displacement in TMJ dysfunction. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows significant disk displacement. The intermediate zone is clearly beyond the condyle, and the angle between the posterior band (dashed line) and vertical (solid line) is close to 50°. (b) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) obtained in a different patient clearly depicts anteromedial disk displacement. The disk (arrow) appears to be "floating" by itself, and the condyle is no longer visualized.
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Figure 8a. Normal disk mobility. (a) Sagittal oblique spin-echo proton-density–weighted MR image (closed-mouth position) shows a disk (arrow) in its normal position between the condyle and temporal bone and centered in the intermediate zone. (Reprinted, with permission, from reference 1.) (b) Sagittal oblique spin-echo proton-density–weighted MR image (open-mouth position) shows that the disk (arrow) has maintained its normal position during condylar movement. This interposition of the disk prevents abnormal contact between osseous joint surfaces.
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Figure 8b. Normal disk mobility. (a) Sagittal oblique spin-echo proton-density–weighted MR image (closed-mouth position) shows a disk (arrow) in its normal position between the condyle and temporal bone and centered in the intermediate zone. (Reprinted, with permission, from reference 1.) (b) Sagittal oblique spin-echo proton-density–weighted MR image (open-mouth position) shows that the disk (arrow) has maintained its normal position during condylar movement. This interposition of the disk prevents abnormal contact between osseous joint surfaces.
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Figure 9a. Anterior disk displacement with reduction. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows an anteriorly displaced disk (arrow). (b) Sagittal oblique gradient-echo T2-weighted MR image (open-mouth position) shows that the disk (arrow) has returned to its normal position between the condyle and the temporal bone. This return movement generally produces a clicking or popping noise.
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Figure 9b. Anterior disk displacement with reduction. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows an anteriorly displaced disk (arrow). (b) Sagittal oblique gradient-echo T2-weighted MR image (open-mouth position) shows that the disk (arrow) has returned to its normal position between the condyle and the temporal bone. This return movement generally produces a clicking or popping noise.
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Figure 10a. Anterior disk displacement without reduction. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows a disk (arrow) displaced from its normal location. (b) On a sagittal oblique gradient-echo T2-weighted MR image obtained in the open-mouth position, the disk (arrow) remains displaced from its normal location. (Reprinted, with permission, from reference 1.)
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Figure 10b. Anterior disk displacement without reduction. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows a disk (arrow) displaced from its normal location. (b) On a sagittal oblique gradient-echo T2-weighted MR image obtained in the open-mouth position, the disk (arrow) remains displaced from its normal location. (Reprinted, with permission, from reference 1.)
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Figure 11a. Stuck disk. On sagittal oblique spin-echo proton-density–weighted MR images obtained in the closed-mouth (a) and open-mouth (b) positions, the posterior band (arrow) remains close to the mandibular fossa. Opening of the jaw in this case was seriously limited.
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Figure 11b. Stuck disk. On sagittal oblique spin-echo proton-density–weighted MR images obtained in the closed-mouth (a) and open-mouth (b) positions, the posterior band (arrow) remains close to the mandibular fossa. Opening of the jaw in this case was seriously limited.
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Figure 12a. Posterior disk displacement. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows a posterior band displaced posteriorly. (b) On a sagittal oblique gradient-echo T2-weighted MR image obtained in the open-mouth position, the posterior band (arrow) remains displaced. The jaw was nearly locked in this case.
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Figure 12b. Posterior disk displacement. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows a posterior band displaced posteriorly. (b) On a sagittal oblique gradient-echo T2-weighted MR image obtained in the open-mouth position, the posterior band (arrow) remains displaced. The jaw was nearly locked in this case.
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Figure 13. Joint effusion. On a sagittal oblique gradient-echo T2-weighted MR image obtained in the closed-mouth position, joint fluid (arrow) clearly delineates the shape of the disk between the upper and lower joint spaces. This phenomenon is best seen on T2-weighted images.
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Figure 14a. Normal retrodiskal tissue. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) clearly depicts the retrodiskal layers (arrow). These structures play an important role in normal disk movement and can easily be visualized at MR imaging. (b) Sagittal oblique spin-echo proton-density–weighted MR image (open-mouth position) shows the superior retrodiskal layer (arrow) between the posterior band and the mandibular fossa. (Reprinted, with permission, from reference 1.)
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Figure 14b. Normal retrodiskal tissue. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) clearly depicts the retrodiskal layers (arrow). These structures play an important role in normal disk movement and can easily be visualized at MR imaging. (b) Sagittal oblique spin-echo proton-density–weighted MR image (open-mouth position) shows the superior retrodiskal layer (arrow) between the posterior band and the mandibular fossa. (Reprinted, with permission, from reference 1.)
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Figure 15a. Abnormal retrodiskal tissue. (a) Sagittal oblique spin-echo proton-density–weighted MR image (open-mouth position) obtained in a patient with internal derangement without reduction shows rupture of the fibers of the superior retrodiskal layer (arrow), resulting in loss of union with the posterior band. (Reprinted, with permission, from reference 1.) (b) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) obtained in a different patient again depicts rupture of the fibers of the superior retrodiskal layer (arrow).
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Figure 15b. Abnormal retrodiskal tissue. (a) Sagittal oblique spin-echo proton-density–weighted MR image (open-mouth position) obtained in a patient with internal derangement without reduction shows rupture of the fibers of the superior retrodiskal layer (arrow), resulting in loss of union with the posterior band. (Reprinted, with permission, from reference 1.) (b) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) obtained in a different patient again depicts rupture of the fibers of the superior retrodiskal layer (arrow).
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Figure 16a. Normal LPM. (a) Sagittal oblique spin-echo proton-density–weighted MR image (closed-mouth position) shows a thin attachment of the inferior LPM (arrow) just below the disk. (b) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows a thin attachment of the superior LPM (arrow) just in front of the disk. (c) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows the thin insertional area of the inferior LPM (arrow). (d) On a sagittal oblique gradient-echo T2-weighted MR image obtained in the open-mouth position, the insertional area of the inferior LPM (arrow) has increased due to contraction of the muscle during this phase.
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Figure 16b. Normal LPM. (a) Sagittal oblique spin-echo proton-density–weighted MR image (closed-mouth position) shows a thin attachment of the inferior LPM (arrow) just below the disk. (b) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows a thin attachment of the superior LPM (arrow) just in front of the disk. (c) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows the thin insertional area of the inferior LPM (arrow). (d) On a sagittal oblique gradient-echo T2-weighted MR image obtained in the open-mouth position, the insertional area of the inferior LPM (arrow) has increased due to contraction of the muscle during this phase.
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Figure 16c. Normal LPM. (a) Sagittal oblique spin-echo proton-density–weighted MR image (closed-mouth position) shows a thin attachment of the inferior LPM (arrow) just below the disk. (b) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows a thin attachment of the superior LPM (arrow) just in front of the disk. (c) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows the thin insertional area of the inferior LPM (arrow). (d) On a sagittal oblique gradient-echo T2-weighted MR image obtained in the open-mouth position, the insertional area of the inferior LPM (arrow) has increased due to contraction of the muscle during this phase.
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Figure 16d. Normal LPM. (a) Sagittal oblique spin-echo proton-density–weighted MR image (closed-mouth position) shows a thin attachment of the inferior LPM (arrow) just below the disk. (b) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows a thin attachment of the superior LPM (arrow) just in front of the disk. (c) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) shows the thin insertional area of the inferior LPM (arrow). (d) On a sagittal oblique gradient-echo T2-weighted MR image obtained in the open-mouth position, the insertional area of the inferior LPM (arrow) has increased due to contraction of the muscle during this phase.
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Figure 17a. Abnormal LPM. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) of a symptomatic TMJ shows complete disk displacement. (b) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) of the contralateral asymptomatic TMJ shows subtle disk displacement. The insertional areas of the superior (arrowhead) and inferior (arrow) LPMs are markedly thinner than those in the symptomatic TMJ (cf a).
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Figure 17b. Abnormal LPM. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) of a symptomatic TMJ shows complete disk displacement. (b) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) of the contralateral asymptomatic TMJ shows subtle disk displacement. The insertional areas of the superior (arrowhead) and inferior (arrow) LPMs are markedly thinner than those in the symptomatic TMJ (cf a).
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Figure 18. Diagram illustrates the relationship between the angle of disk displacement in degrees (x-axis) and the diameter of the inferior LPM attachment in millimeters (y-axis) in the closed-mouth position. The diagram shows a significant relationship between the two variables: As the angle of disk displacement increases, the diameter of the muscle attachment also increases. The statistical Altman test was performed.
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Figure 19a. Double disk sign. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) of a symptomatic TMJ shows complete disk displacement. The thick insertional area of the inferior LPM (arrow) is parallel to the disk (arrowhead), creating the double disk sign. (Reprinted, with permission, from reference 1.) (b) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) of a symptomatic TMJ in a different patient demonstrates severe internal derangement (arrowhead). A thick inferior LPM attachment (arrow) is again seen. The double disk sign must be recognized to distinguish between disk and muscle attachment.
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Figure 19b. Double disk sign. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) of a symptomatic TMJ shows complete disk displacement. The thick insertional area of the inferior LPM (arrow) is parallel to the disk (arrowhead), creating the double disk sign. (Reprinted, with permission, from reference 1.) (b) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) of a symptomatic TMJ in a different patient demonstrates severe internal derangement (arrowhead). A thick inferior LPM attachment (arrow) is again seen. The double disk sign must be recognized to distinguish between disk and muscle attachment.
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Figure 20a. Osteoarthritic changes in four different patients. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) obtained in a patient with internal derangement shows condylar flattening (arrow). (b) Sagittal oblique gradient-echo T2-weighted MR image (open-mouth position) obtained in a patient with internal derangement without reduction clearly depicts an osteophyte (arrow). (c) Sagittal oblique spin-echo T2-weighted MR image (closed-mouth position) obtained in a patient with internal derangement shows condylar erosion (arrow). (d) Sagittal oblique gradient-echo T2-weighted MR image (open-mouth position) obtained in a patient with internal derangement without reduction demonstrates a condylar osteophyte, flattening, sclerosis, and erosion (arrow), all of which are signs of osteoarthritic changes (cf a–c).
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Figure 20b. Osteoarthritic changes in four different patients. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) obtained in a patient with internal derangement shows condylar flattening (arrow). (b) Sagittal oblique gradient-echo T2-weighted MR image (open-mouth position) obtained in a patient with internal derangement without reduction clearly depicts an osteophyte (arrow). (c) Sagittal oblique spin-echo T2-weighted MR image (closed-mouth position) obtained in a patient with internal derangement shows condylar erosion (arrow). (d) Sagittal oblique gradient-echo T2-weighted MR image (open-mouth position) obtained in a patient with internal derangement without reduction demonstrates a condylar osteophyte, flattening, sclerosis, and erosion (arrow), all of which are signs of osteoarthritic changes (cf a–c).
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Figure 20c. Osteoarthritic changes in four different patients. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) obtained in a patient with internal derangement shows condylar flattening (arrow). (b) Sagittal oblique gradient-echo T2-weighted MR image (open-mouth position) obtained in a patient with internal derangement without reduction clearly depicts an osteophyte (arrow). (c) Sagittal oblique spin-echo T2-weighted MR image (closed-mouth position) obtained in a patient with internal derangement shows condylar erosion (arrow). (d) Sagittal oblique gradient-echo T2-weighted MR image (open-mouth position) obtained in a patient with internal derangement without reduction demonstrates a condylar osteophyte, flattening, sclerosis, and erosion (arrow), all of which are signs of osteoarthritic changes (cf a–c).
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Figure 20d. Osteoarthritic changes in four different patients. (a) Sagittal oblique gradient-echo T2-weighted MR image (closed-mouth position) obtained in a patient with internal derangement shows condylar flattening (arrow). (b) Sagittal oblique gradient-echo T2-weighted MR image (open-mouth position) obtained in a patient with internal derangement without reduction clearly depicts an osteophyte (arrow). (c) Sagittal oblique spin-echo T2-weighted MR image (closed-mouth position) obtained in a patient with internal derangement shows condylar erosion (arrow). (d) Sagittal oblique gradient-echo T2-weighted MR image (open-mouth position) obtained in a patient with internal derangement without reduction demonstrates a condylar osteophyte, flattening, sclerosis, and erosion (arrow), all of which are signs of osteoarthritic changes (cf a–c).
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Copyright © 2006 by the Radiological Society of North America.
