Flexor Digitorum Profundus and Flexor Digitorum Superficialis Repair Superior for Zone II Flexor Tendon Repair

Editor’s note: The following content was originally scheduled for the AAOS Now Daily Edition, which publishes each year onsite at the AAOS Annual Meeting, but this year’s meeting in March was canceled due to COVID-19. Despite the cancellation, members can access virtual content from the Annual Meeting by visiting the Academy’s Annual Meeting Virtual Experience webpage at aaos.org/VirtualAAOS2020.

A study that was presented as part of the Annual Meeting Virtual Experience compared flexor digitorum profundus (FDP) repair versus FDP and flexor digitorum superficialis (FDS) repair in Hispanic patients with flexor tendon laceration of FDP and FDS in zone II. The researchers concluded that FDP/FDS primary repair was more effective than FDP repair and FDS excision at three months.

“Hand flexor zone II injuries have been reported as the most common area of all flexor tendon zones injuries,” Eduardo J. Natal-Albelo, MD, a post-graduate year-5 orthopaedic surgery resident at the University of Puerto Rico Medical Sciences Campus, told AAOS Now. “Nonetheless, little is known about a possible standard of care in this population due to the ambiguity on the surgical repair of zone II lacerations.”

The researchers conducted a prospective cohort study of 25 zone II flexor tendon injury patients, who were stratified into two groups: primary FDP tendon repair (FDP group; n = 14) and primary FDP and FDS tendons repair (FDP/FDS group; n = 11). Postoperative range of motion (ROM) and patient outcomes were recorded; other factors studied included demographics, clinical neurovascular examination outcomes, and complications.

The FDP/FDS group had superior 12-week patient outcomes and ROM. Metacarpal-phalangeal joint ROM was higher in the FDP group (P = 0.02), whereas the FDP/FDS group had higher ROM in the proximal (P < 0.02) and distal (P < 0.01) interphalangeal joints. Disabilities of the Arm, Shoulder, and Hand (DASH) scores were better in the FDP/FDS group (10.1 versus 23.3; P < 0.01), as was total active motion (TAM) (57.9 percent versus 44.0 percent; P < 0.01). At 24 weeks, both cohorts demonstrated further improvement. DASH scores remained better in the FDP/FDS group (6.4 versus 10.4; P = 0.07), as did TAM (76.2 percent versus 73.4 percent). See Table 1 for all outcomes.

“FDP/FDS primary repair resulted in more effective results, providing less restrictions on their daily activities and increasing overall functional performance,” said Dr. Natal-Albelo. “This study emphasizes the importance of the use of DASH and TAM scores as measuring tools in patients undergoing surgical repair of zone II lacerations.”

The study is limited by its small patient population. In addition, due to the limited timeframe, the researchers could not closely analyze psychological aspects of the trauma.

Dr. Natal-Albelo recently published this study in the September issue of the Journal of the AAOS Global Research & Reviews ®.

Dr. Natal-Albelo’s coauthors of “Functional and Disability Assessment Among Hispanics With Zone 2 Flexor Tendon Injuries: Comparative Study Between Flexor Digitorum Superficialis Repair and Flexor Digitorum Superficialis Excision” are Gerardo Olivella, MD, MPH; Giovanni U. Paraliticci-Márquez, MD; Lenny Rivera, MD; Gabriel Echegaray, MD; Norman Ramirez, MD; and Christian A. Foy-Parrilla, MD, FAAOS.

Kaitlyn D’Onofrio is the associate editor for AAOS Now. She can be reached at kdonofrio@aaos.org.