title: The effect of a collagen-elastin matrix on adhesion formation after flexor tendon repair in a rabbit model.
abstract: OBJECTIVE
  The outcome of flexor tendon surgery is negatively affected by the formation of adhesions which can occur during the healing of the tendon repair. In this experimental study, we sought to prevent adhesion formation by wrapping a collagen-elastin scaffold around the repaired tendon segment.
  
  
  METHODS
  In 28 rabbit hind legs, the flexor tendons of the third and fourth digits were cut and then repaired using a two-strand suture technique on the fourth digit and a four-strand technique on the third digit. Rabbits were randomly assigned to study and control groups. In the control group, the operation ended by closing the tendon sheath and the skin. In the study group, a collagen-elastin scaffold was wrapped around the repaired tendon segment in both digits. After 3 and 8 weeks, the tendons were harvested and processed histologically. The range of motion of the digits and the gap formation between the repaired tendon ends were measured. The formation of adhesions, infiltration of leucocytes and extracellular inflammatory response were quantified.
  
  
  RESULTS
  At the time of tendon harvesting, all joints of the operated toes showed free range of motion. Four-strand core sutures lead to significantly less diastasis between the repaired tendon ends than two-strand core suture repairs. The collagen-elastin scaffold leads to greater gapping after 3 weeks compared to the controls treated without the matrix. Within the tendons treated with the collagen-elastin matrix, a significant boost of cellular and extracellular inflammation could be stated after 3 weeks which was reflected by a higher level of CAE positive cells and more formation of myofibroblasts in the αSMA stain in the study group. The inflammatory response subsided gradually and significantly until the late stage of the study. Both the cellular and extracellular inflammatory response was emphasized with the amount of material used for the repair.
  
  
  CONCLUSIONS
  The use of a collagen-elastin matrix cannot be advised for the prevention of adhesion formation in flexor tendon surgery, because it enhances both cellular and extracellular inflammation. Four-strand core sutures lead to less gapping than two-strand core sutures, but at the same time, the cellular and extracellular inflammatory response is more pronounced.
authors.affiliation: Abteilung für Unfall-, Hand- und Wiederherstellungschirurgie, Chirurgische Universitätsklinik Rostock, Schillingallee 35, 18055, Rostock, Germany. alice.wichelhaus@med.uni-rostock.de.
authors.forename: Dagmar Alice
authors.initials: DA
authors.lastname: Wichelhaus
authors.affiliation: Abteilung für Unfall-, Hand- und Wiederherstellungschirurgie, Chirurgische Universitätsklinik Rostock, Schillingallee 35, 18055, Rostock, Germany.
authors.forename: Sascha Tobias
authors.initials: ST
authors.lastname: Beyersdoerfer
authors.affiliation: Abteilung für Unfall-, Hand- und Wiederherstellungschirurgie, Chirurgische Universitätsklinik Rostock, Schillingallee 35, 18055, Rostock, Germany.
authors.forename: Philip
authors.initials: P
authors.lastname: Gierer
authors.affiliation: Rudolf-Zenker-Institut für Experimentelle Chirurgie und zentrale Versuchstierhaltung, Universitätsmedizin Rostock, Schillingallee 69a, 18057, Rostock, Germany.
authors.forename: Brigitte
authors.initials: B
authors.lastname: Vollmar
authors.affiliation: Abteilung für Unfall-, Hand- und Wiederherstellungschirurgie, Chirurgische Universitätsklinik Rostock, Schillingallee 35, 18055, Rostock, Germany.
authors.forename: Th
authors.initials: T
authors.lastname: Mittlmeier
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D003094:Collagen / Q000009:adverse effects / Q000494:pharmacology*; D004549:Elastin / Q000009:adverse effects / Q000494:pharmacology*; D005260:Female; D011817:Rabbits; D016059:Range of Motion, Articular; D013536:Suture Techniques / Q000009:adverse effects; D013708:Tendon Injuries / Q000601:surgery*; D013710:Tendons / Q000601:surgery*; D000267:Tissue Adhesions / Q000209:etiology / Q000517:prevention & control*; D054457:Tissue Scaffolds / Q000009:adverse effects / Q000737:chemistry*; D014945:Wound Healing
chemical_list: D003094:Collagen; D004549:Elastin
keywords: Elastin-collagen-scaffold; Flexor tendon repair; Inflammatory response; Peritendinous adhesion formation