Utility of ultrasound imaging in the diagnosis of postoperative complications following upper extremity tendon repair

Abstract

Operated tendons are impacted by an inciting trauma and the subsequent treatment and will never again appear as they were prior to the insult. Post-operative tendons have unique ultrasound (US) findings that can be helpful to the surgeon in evaluating the success of repair, status of healing and confirmation that the repair remains intact. The advantage of US over physical exam or other imaging modalities is that it offers both static and dynamic assessment. The latter is of particular benefit in evaluating tendon function and gliding, which are meant to be visualized dynamically in order to provide information for the hand surgeon in defining the post-operative course. The goal of the pictorial review is to comprehensively present the US findings for postoperative complications in this field including tendon rupture, gapping, adhesion, suture granuloma and pulley disruption. Competence with ultrasound-assisted diagnosis in these domains can provide prompt feedback for providers and insight to improve patient care.

Keywords: Rupture; Suture; Tendon; Ultrasound.

Fig. 1

Sonographic Image of Physiologic Postoperative Tendon Healing Figure I. Case of physiologic healing following primary suture repair of the third digit common extensor tendon at the level of the metacarpal head. Longitudinal sonographic image showing that the proximal (thin arrows) and distal (thick arrows) portions of the tendon are united without a gap. Echogenic material (curved arrow) within the tendon is consistent with suture material. This is compatible with successful tendon repair.

Fig. 2

Sonographic Images of Complete Tendon Rupture Figure II. Case of tendon rupture following repair of a fifth digit flexor digitorum profundus (FDP) tendon that had been repaired primarily 2 weeks prior. The patient had removed her splint and felt a popping sensation in the digit. Transverse (A) and longitudinal (B) US images of the surgical area confirm the diagnosis. On the right, the proximal stump (thin arrows) and distal stump (thick arrows) are separated by a gap (G) measuring 9 ​mm long. Echogenic material in the distal stump (curved arrow on the left-hand image) is consistent with suture material. This is compatible with complete tendon rupture and retraction after failed repair. The imaging findings were later confirmed intraoperatively during a re-repair.

Fig. 3

Sonographic Images of Suture Gapping Figure III. Case of a woman who lacerated her fourth digit FDP tendon after breaking a glass cup. She had the tendon repaired primarily in the operating room. Approximately a month and a half afterwards, she demonstrated an inability to flex her distal phalanx. Longitudinal (A) and transverse (B) US images show a gap at the repair site. The sharp edges of the proximal (thin arrow) and distal (thick arrow) transected tendon are displaced by 1.1 ​cm. On the left, there is a hypoechoic gap (G) filled with fluid between the tendon margins. The echogenic sutures still attached to the tendons are clearly visible crossing the gap and in the tendon margin (curved arrows in both images). An echogenic linear structure deep to the tendon is the middle phalangeal cortex (arrow heads).

Fig. 4

Sonographic Image of Postoperative Scar Adhesion Figure IV. Case of a young woman who accidently cut the volar aspect of her thumb with a knife and severed the flexor pollicis longus (FPL) tendon. She underwent primary suture repair of the tendon. Several weeks after the repair, she was unable to flex the tip of her thumb and was sent for evaluation. Longitudinal US image reveals restriction in gliding of the FPL tendon at the level of the proximal phalangeal base after repair. Sutures (curved arrows) are visualized in the mid substance of the tendon (straight arrows). A hypoechoic mass (arrow heads) is slightly compressing the superficial surface of the tendon and is consistent with restricting adhesions.

Fig. 5

Sonographic Images of a Repair-site Suture Granuloma Figure V. Case of a patient who lacerated a common extensor tendon from a piece of broken glass. She underwent uneventful primary suture repair. A few months later, she noticed a palpable, occasionally tender dorsal hand mass overlying the metacarpophalangeal (MCP) joint. She was referred for sonographic analysis. Longitudinal (A) and transverse (B) US images demonstrate a curved echogenic structure with a braided texture (curved arrows). This is consistent with a suture knot from the repaired tendon ends (between the thin arrows) at the MCP joint level. The superficial portion of the suture is curving within the hypoechoic mass (between the arrow heads) suggestive of a suture granuloma.

Fig. 6

Sonographic Image of Pulley Disruption Figure VI. Case of a patient who sustained a laceration to the fifth digit FDP tendon and underwent primary suture repair in the operating room. Several weeks following the repair, she noticed only minimal flexion across the distal interphalangeal joint, and there was no appreciable change with therapy. Rupture of the repair was suspected, and she was sent for US. Longitudinal US image demonstrates that the repaired FDP tendon (between the long arrows) was lifted from the volar surface of the phalanx (arrow heads) consistent with tendon bowstringing. This is concerning for tear of the pulleys. Echogenic material in the distal aspect of the tendon (curved arrow) is consistent with suture material.