Triangular fibrocartilage and intercarpal ligaments of the wrist: MR imaging. Cadaveric study with gross pathologic and histologic correlation.

Abstract

To provide further understanding of the magnetic resonance (MR) signal intensities in the triangular fibrocartilage (TFC) and interosseous ligaments of the wrist, the authors performed MR imaging with gross pathologic and histologic analysis in 10 cadaveric wrists. Spin-echo T1- and T2-weighted coronal images were obtained, and 3-mm coronal sections of the specimens were then made that correlated precisely with the MR images. Normal portions of the TFC showed asymmetrical bow tie-like low signal intensity, except near the radial and ulnar attachments. Degeneration of the TFC, present in all cases, was more severe on the proximal surface and was characterized by high signal intensity on T1-weighted images and less high signal intensity on T2-weighted images. These findings differed from those in TFC perforation, which showed high signal intensity on T2-weighted images. Similar signal intensity characteristics could allow differentiation of degeneration and perforation of the scapholunate and lunotriquetral ligaments. These findings suggest that in vivo MR imaging may accurately delineate degeneration and perforation of the TFC and intercarpal ligaments.

Prevalence of Triangular Fibrocartilage Complex Abnormalities on MRI Scans of Asymptomatic Wrists

“…Furthermore, we identified focal regions of centrally increased intrasubstance signal in 8 subjects, a finding that may be linked to mucinous degeneration of the TFCC. 11,26 Because we found a correlation between TFCC abnormalities and age, and because our study population was relatively young (mean age of 34 Ϯ 10 y), we expect that in time some of the degenerative TFCCs may develop a tear and that a correlation between the age and the presence of a full-thickness tear may become evident.…”

Characteristics of Triangular Fibrocartilage Defects in Symptomatic and Contralateral Asymptomatic Wrists

“…This dense distally located fibrous connective tissue seems less likely to undergo degeneration than the proximal-sided cartilage of the TFC and the proximally located laminae (20). The predominance of the degeneration of the proximal side of the TFC also has been explained by more intensive biomechanical forces in this region (20). We hypothesize that, as long as the dense distally located laminae are intact, a noncommunicating defect appears more likely to occur than a communicating defect.…”

“…The more distal laminae extend beyond the ulna and blend with the dense fibrous connective tissue of the prominent sheath of the extensor carpi ulnaris tendon (19). This dense distally located fibrous connective tissue seems less likely to undergo degeneration than the proximal-sided cartilage of the TFC and the proximally located laminae (20). The predominance of the degeneration of the proximal side of the TFC also has been explained by more intensive biomechanical forces in this region (20).…”

MR imaging of the traumatic triangular fibrocartilaginous complex tear

“…Mucoid degeneration will render the TFCC high signal intensity on short TE sequence, i.e., T1-weighted and proton-density sequences simulating tears (49). This alteration in signal intensity reflects alteration in the water binding property of the TFCC disk (50).…”