Pulley Tears

Fig. 11.46a,b. Acute complete A3 and A4 pulley tears in an extreme rock climber, a Longitudinal 12-5 MHz US image with b Tl-weighted MR imaging correlation shows coexistent volar displacement (double arrows) of the flexor digitorum superficialis (arrows) over the head of the proximal phalanx (PP) and of the flexor digitorum profundus (asterisk) at the level of the head of the proximal phalanx and over the proximal half of the middle phalanx (MP). This is because the flexor digitorum superficialis has a more proximal insertion into the shaft of the middle phalanx... 

US findings of annular pulley tears correlate well with the MR imaging findings (Bodner et al. 1999). 

Other imaging modalities, such as MR imaging and CT scan, are able to identify annular pulley tears (Le Viet et al. 1996 Parelleda et al. 1996 Hauger et al. 2000), but are expensive and time-consuming. US can be considered an effective and less expensive alternative, capable of static and dynamic observations. 

Manthey DE,StorrowAB,Milbourn JM et al (1996) Ultrasound versus radiography in the detection of soft-tissue foreign bodies. Ann Emerg Med 28 7-9 Markham DE, Wood MR (1980) Ultrasound for Dupuytren s contracture. Physiotherapy 66 55-58 Martinoli C, Bianchi S, Derchi LE et al (2000) Sonographic evaluation of digital annular pulleys tears. Skeletal Radiol 29 387-391... 

Split-tear test pieces were prepared by die stamping on a thin flat sheet of vulcanized rubber of uniform thickness. The test piece was clamped by a grip, and a dead load apphed to the other end of the test piece via a fiictionless pulley. A dead load, which... 

Fig. 11.43a,b. Postsurgical findings in a patient previously operated on for flexor tendon tear, a Transverse and b longitudinal 15-7 MHz US images obtained over the palmar aspect of the proximal phalanx (PP) demonstrate palmar discontinuity of the A2 pulley as a result of surgical section. Arrows indicate the free edges of the pulley. The medial and lateral limbs of the pulley are thickened and hypoechoic. Note the presence of surgical stitches (arrowheads) in the repaired flexor tendons (ft)... 

Acute tears of the annular pulleys are mainly secondary to maximal resisted flexion of the fingers. These injuries are typically encountered in rock climbers, who must hold the body weight on the flexed fingers during climbing (Bollen 1990). In... 

In high-level professional climbers, the A2 and A4 pulleys should be usually reconstructed after a complete tear to restore efficient biomechanical characteristics of the flexor apparatus, whereas laceration of the other, less critical, pulleys would usually not require surgical repair. Multiple loops of free tendon or retinaculum grafts are used for digital pulley reconstruction, placing the grafts in the same location as the native pulley. A segment of pal-... 

Apart from the traumatic setting, loosening of the pulleys may be secondary to inflammatory or infectious tenosynovitis. In these disorders, chronic inflammation can lead to distension of the pulleys with secondary functional impairment rather than true tears. A typical case of pulley involvement occurs in patients with rheumatoid arthritis due to pannus activity (see paragraph Sect. 11.5.4.2). 

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