In vivo cervical facet joint capsule deformation during flexion-extension.

STUDY DESIGN: Nonrandomized controlled cohort. OBJECTIVE: To characterize subaxial cervical facet joint kinematics and facet joint capsule (FJC) deformation during in vivo, dynamic flexion-extension. To assess the effect of single-level anterior arthrodesis on adjacent segment FJC deformation. SUMMARY OF BACKGROUND DATA: The cervical facet joint has been identified as the most common source of neck pain, and it is thought to play a role in chronic neck pain related to whiplash injury. Our current knowledge of cervical facet joint kinematics is based on cadaveric mechanical testing. METHODS: Fourteen asymptomatic controls and 9 C5-C6 arthrodesis patients performed full range of motion flexion-extension while biplane radiographs were collected at 30 Hz. A volumetric model-based tracking process determined 3-dimensional vertebral position with submillimeter accuracy. FJC fibers were modeled and grouped into anterior, lateral, posterior-lateral, posterior, and posterior-medial regions. FJC fiber deformations (total, shear, and compression-distraction) relative to the static position were determined for each cervical motion segment (C2-C3 through C6-C7) during flexion-extension. RESULTS: No significant differences in the rate of fiber deformation in flexion were identified among motion segments (P = 0.159); however, significant differences were observed among fiber regions (P < 0.001). Significant differences in the rate of fiber deformation in extension were identified among motion segments (P < 0.001) and among fiber regions (P = 0.001). The rate of FJC deformation in extension adjacent to the arthrodesis was 45% less than that in corresponding motion segments in control subjects (P = 0.001). CONCLUSION: In control subjects, FJC deformations are significantly different among vertebral levels and capsule regions when vertebrae are in an extended orientation. In a flexed orientation, FJC deformations are different only among capsule regions. Single-level anterior arthrodesis is associated with significantly less FJC deformation adjacent to the arthrodesis when the spine is in an extended orientation. LEVEL OF EVIDENCE: 4.

Synovial chondromatosis of the temporomandibular joint: an asymptomatic case report and literature review.

Synovial chondromatosis of the temporomandibular joint (TMJ) is a rare lesion characterized by the presence of loose bodies in the glenoid fossa. Swelling, unilateral pain, occlusal changes, clicking, crepitation, deviation, and limited mandibular function are the most common characteristics, although this combination is not always apparent. Radiopacities of the TMJ should be thoroughly investigated as some signals and symptoms may be not present or combined, taking months or even years to confirm a diagnosis. A case report is presented here with a brief literature review, where surgical removal was the therapy of choice, calling attention to the absence of symptoms and some signals, which may mislead final diagnosis.

Vacuum phenomenon in the temporomandibular joint: a clinical, computed tomography and magnetic resonance case report.

A 28-year-old woman presented with a history of clicking and mandibular clenching. She was studied clinically and with axial and coronal CT. The patient was going through a tense emotional period and reported tightening of her teeth (clenching); she was under psychological and neurological treatment for depression including pharmacological therapy. She presented slight pain only at maximum mouth opening at the right temporomandibular joint (TMJ) and in the lateral pole on palpation; there was no coincidence between initial and maximal interocclusal contacts because of premature dental contacts. She showed occlusal group function in the right side and canine guidance in the left side with a right contact of balance, local muscular pain in the right deep masseter muscle and in the superior and middle portion of the right trapezium on palpation. On CT, a spherical area of 3 mm diameter with an average density of -647 HU (SD+/-4.7) was found in the upper and posterior area of the lower space of the right TMJ, together with a thicker lower synovial tissue. This observation was confirmed by MRI. Like other joints, the TMJ could present vacuum phenomenon images inside synovial tissue in the presence of degenerative disease. It is important for radiologists to recognize this rare entity.

Ultrasound and tomographic evaluation of temporomandibular joints in adolescents with and without signs and symptoms of temporomandibular disorders: a pilot study.

OBJECTIVES: Condylar position in the glenoid fossa has been linked to temporomandibular disorders (TMDs); however its importance in TMD aetiology is still unclear. The purpose of this study was to determine joint spaces and condylar position in adolescents with TMDs using ultrasound static images and linear corrected tomograms at the mandibular rest position. METHODS: Craniomandibular index (CMI) and a symptom questionnaire were assessed in 217 subjects aged 12-18 years. Those with the lowest and the highest scores were divided into control (n=20) and SSTMD (presence of signs and symptoms of TMD) groups (n=20). Ultrasound images and tomography were used to measure the distance between the capsule and the lateral surface of the condyle and to determine the condyle location at the mandibular resting position, respectively. RESULTS: The mean distances obtained from ultrasound images did not correlate with CMI scores and they did not differ between the two groups (P>0.05). Posterior positioned condyles were determined on tomograms, and they were more prevalent both in the SSTMD group (P=0.05) and in girls (P<0.05). CONCLUSIONS: Even though there was a significant difference in condyle position between the control and SSTMD groups, determined by axially corrected tomograms, it cannot be inferred that posteriorly positioned condyles can predict TMDs. In addition, there was no association between the articular capsule and the lateral condyle surface distances measured by ultrasound using a 10 MHz linear transducer and the clinical diagnosis of TMD. Further studies in diagnostic imaging of TMJs with ultrasound should be encouraged, since it has some useful diagnostic applications and does not require special facilities.

Ultrasound in adhesive capsulitis of the shoulder: is assessment of the coracohumeral ligament a valuable diagnostic tool?

OBJECTIVE: To determine the accessibility of the coracohumeral ligament (CHL) by ultrasound (US) and to determine CHL thickness in adhesive capsulitis of the shoulder. DESIGN AND PATIENTS: US examinations were carried out in 498 consecutive shoulders of 306 individuals (194 women and 112 men), mean age 47.4 years (range 15-92 years), in order to identify and measure the maximum thickness of the CHL. The patients were divided into three study groups: asymptomatic shoulders (n=121), painful shoulders (n=360) and shoulders with arthrographic evidence of adhesive capsulitis (n=17). The mean maximal thickness of CHL was compared among the 3 study groups (non-parametric test of Kruskal-Wallis, p<0.05). RESULTS: The CHL was visualized in 92 out of 121 shoulders in the asymptomatic group (76.0%), in 227 out of 360 shoulders in the painful shoulder group (63.0%), and in 15 out of 17 shoulders in the adhesive capsulitis group (88.2%). The average thickness of the CHL was significantly greater in adhesive capsulitis (3 mm) than in the asymptomatic (1.34 mm) and painful (1.39 mm) shoulders. No significant difference was found between asymptomatic and painful shoulders. CONCLUSION: CHL depiction can be achieved in a reasonable proportion of shoulders. A thickened CHL is suggestive of adhesive capsulitis. More studies are needed for clinical validation of these data.

Roentgenographic assessment of acromial morphologic condition in rotator cuff impingement syndrome.

Patients with an isolated diagnosis of rotator cuff impingement syndrome were prospectively entered into the study. Each of the 23 subjects was refractory to conservative therapy, had preoperative roentgenograms, and underwent an open acromioplasty. The roentgenograms included anteroposterior, axillary, 30 degrees caudal tilt, and supraspinatus outlet views. The roentgenograms were measured by four independent readers. The separate views were then scored for reliability, and the correlation of the measurements with intraoperative acromial measurements was assessed. Interobserver reliability was highest for the caudal tilt view (0.84) and lowest for the axillary view (0.09). The supraspinatus and caudal tilt views correlated significantly with distinct intraoperative measurements of acromial spur size. We continue to advocate the evaluation of both views for preoperative assessment of the acromial spur in the rotator cuff impingement syndrome.