title: Treatment options and outcome after bony avulsion of the flexor digitorum profundus tendon: a review of 29 cases.
abstract: BACKGROUND
  The objective of this retrospective review was to evaluate the functional and esthetic outcomes in patients with non- or minimally (<2 mm), and severely (>2 mm) displaced bony avulsions of the flexor digitorum profundus (FDP) tendon.
  
  
  METHODS
  Between 1996 and 2010, 29 patients with a bony avulsion of the FDP tendon were treated. The displacement magnitude of the avulsed fragment determined, whether conservative or surgical treatment was performed. Persisting functional deficit, radiological findings, remaining disabilities using the Disability of the Arm, Shoulder, and Hand (DASH) score, as well as treatment-related deformities and complications were evaluated retrospectively and at a mean follow-up of 7 years.
  
  
  RESULTS
  In 16 patients, conservative therapy by initial static splinting due to a fragment displacement of <2 mm was conducted. These patients reported no functional impairment at follow-up. In 13 cases, major displacement (>2 mm) of the bony fragment led to an open reconstruction of the avulsion injury either by screw fixation or a Lengemann pull-out wire. In a majority, an extension deficit in the DIP joint and a decrease of tip pinch strength by 25% was present at follow-up. In five patients, peri- or short-term postoperative complications occurred and in five, a nail deformity remained. DASH score revealed satisfying results after both therapeutic approaches.
  
  
  CONCLUSIONS
  Conservative treatment in non- or minimally displaced avulsions leads to satisfying functional results. Patients receiving surgery after major fragment displacement need to be aware of a possible impaired ROM at the DIP joint. The use of the Lengemann pull-out wire may place patients at an increased complication risk and frequently induces nail deformities.
  
  
  METHODS
  Therapeutic, level IV.
authors.affiliation: University Clinic for Trauma Surgery, Medical University Vienna, Währinger Gürtel, 18-20, 1090, Vienna, Austria. gabriel.halat@meduniwien.ac.at.
authors.forename: Gabriel
authors.identifier: http://orcid.org/0000-0002-2480-7381
authors.initials: G
authors.lastname: Halát
authors.affiliation: University Clinic for Trauma Surgery, Medical University Vienna, Währinger Gürtel, 18-20, 1090, Vienna, Austria.
authors.forename: Lukas
authors.initials: L
authors.lastname: Negrin
authors.affiliation: University Clinic for Trauma Surgery, Medical University Vienna, Währinger Gürtel, 18-20, 1090, Vienna, Austria.
authors.forename: Jochen
authors.initials: J
authors.lastname: Erhart
authors.affiliation: Section for Medical Statistics, Center for Medical Statistics, Informatics, and Intelligent Systems, Medical University Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria.
authors.forename: Robin
authors.initials: R
authors.lastname: Ristl
authors.affiliation: University Clinic for Trauma Surgery, Medical University Vienna, Währinger Gürtel, 18-20, 1090, Vienna, Austria.
authors.forename: Stefan
authors.initials: S
authors.lastname: Hajdu
authors.affiliation: University Clinic for Trauma Surgery, Medical University Vienna, Währinger Gürtel, 18-20, 1090, Vienna, Austria.
authors.forename: Patrick
authors.initials: P
authors.lastname: Platzer
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001863:Bone Screws; D001864:Bone Wires; D005260:Female; D005383:Finger Injuries / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000379:methods*; D012189:Retrospective Studies; D013708:Tendon Injuries / Q000601:surgery*; D055815:Young Adult
keywords: Bony flexor digitorum profundus tendon avulsion treatment; Flexor digitorum profundus tendon repair; Flexor tendon injury; Jersey finger