Practical ultrasonographic technique to precisely identify and differentiate tendons and ligaments of the elbow at the level of the humeral epicondyles: anatomical study.

OBJECTIVES: To develop a practical step-by-step technique to precisely identify and differentiate tendons and ligaments attaching to the humeral epicondyles, to confirm through gross anatomical study the accurate structure identification provided by this technique and to determine the frequency at which each structure can be identified in healthy volunteers. MATERIALS AND METHODS: First, ten fresh frozen cadavers (6 men, age at death = 58-92 years) were examined by two musculoskeletal radiologists and a step-by-step technique for the identification of tendons and ligaments at the level of humeral epicondyles was developed. Second, the accurate identification of structures was confirmed through gross anatomical study including anatomical sections on five specimens and layer-by-layer dissection technique on five others. Finally, 12 healthy volunteers (6 men, average age = 36, range = 28-52) were scanned by two radiologists following the same technique. RESULTS: An ultrasonographic technique based on the recognition of bony landmarks and the use of ultrasonographic signs to differentiate overlapping structures was developed and validated through gross anatomical study. In healthy volunteers, most tendons and ligaments were identified and well-defined in ≥ 80% of cases, except for the extensor carpi radialis brevis and extensor digiti minimi tendons on the lateral epicondyle (having common attachments with the extensor digitorum communis) and the palmaris longus tendon on the medial epicondyle (absent, or common attachment with the flexor carpi radialis). CONCLUSION: A step-by-step approach to the ultrasonographic assessment of tendons and ligaments at the humeral epicondyles allowed accurate identification of and differentiation among these structures, in particular those relevant to pathological conditions.

Deep and superficial infrapatellar bursae: cadaveric investigation of regional anatomy using magnetic resonance after ultrasound-guided bursography.

OBJECTIVE: To demonstrate the anatomy of the deep and superficial infrapatellar bursae using magnetic resonance (MR) imaging and anatomic correlation in cadavers. DESIGN: MR imaging of the infrapatellar bursae of nine cadaveric knees was performed after ultrasound-guided bursography. The images were compared with those seen on anatomic sectioning. Histologic analysis was obtained in two specimens. RESULTS: The deep infrapatellar bursa (DIB) was visualized in all specimens (n=9) and the superficial infrapatellar bursa (SIB) in five specimens (55%). The mean dimensions of the DIB in the craniocaudal, mediolateral, and anteroposterior planes were respectively 25, 28.7, and 6 mm, and for SIB 19.5, 21.2 and 2.2 mm. A fat apron dividing the DIB was depicted in eight knees (89%). Lateral extension of the DIB beyond the patellar tendon was observed in 100% of cases. Cadaveric analysis depicted a thin septum in the SIB in four of five cases (80%). CONCLUSIONS: The DIB is generally present and extends beyond the lateral margin of the patellar tendon. A fat apron partially separating this structure is usual. The SIB is not an unusual finding and may have a septum separating its compartments.

Radial and ulnar bursae of the wrist: cadaveric investigation of regional anatomy with ultrasonographic-guided tenography and MR imaging.

OBJECTIVE: To demonstrate the anatomy of the radial and ulnar bursae of the wrist using MR and US images. DESIGN: Ultrasonographic-guided tenography of the tendon sheath of flexor pollicis longus (FPL) and the common tendon sheath of the flexor digitorum of the fifth digit (FD5) of ten cadaveric hands was performed, followed by magnetic resonance imaging and gross anatomic correlation. Patterns of communication were observed between these tendon sheaths and the radial and ulnar bursae of the wrist. RESULTS: The tendon sheath of the FPL communicated with the radial bursa in 100% (10/10) of cases, and the tendon sheath of the FD5 communicated with the ulnar bursa in 80% (8/10). Communication of the radial and ulnar bursae was evident in 100% (10/10), and presented an "hourglass" configuration in the longitudinal plane. CONCLUSIONS: The ulnar and radial bursae often communicate. The radial bursa communicates with the FPL tendon sheath, and the ulnar bursa may communicate with the FD5 tendon sheath.