title: [The effect of low-molecular-weight heparin on rat tendon healing].
abstract: OBJECTIVE
  We investigated the effect of low-molecular-weight heparin (LMWH) on the healing of tendons.
  
  
  METHODS
  Forty-five adult Wistar rats weighing 300 g were randomized into three groups equal in number. All the rats underwent full-thickness surgical incision of the Achilles tendon followed by primary repair. After the operation, two groups received daily subcutaneous LMWH injections (nadroparin calcium) for four weeks at high or low doses (group I, 6 mg/kg, 170 IU AXa; group II, 3 mg/kg, 85 IU AXa). Group III remained untreated as the control group. Histologically, the specimens were examined under light and electron microscopy with regard to the amount of fibrillar collagen synthesis, mitochondrial degeneration, and the composition of the extracellular matrix collagen. Biomechanically, maximum load to failure and correspondent elongation of the tendons were measured.
  
  
  RESULTS
  Compared to the control group, histologically, both LMWH-treated groups exhibited increased number of fibroblasts, increased fibrillar collagen formation in the extracellular matrix, and higher counts of granular endoplasmic reticula in cytoplasmic contents of fibroblasts as well as decreased mitochondrial vacuolization and degeneration. Biomechanical assessments showed that tendons in group I had significantly higher maximum load to failure and elongation values than group II and III (31 N vs. 24.6 N and 23.1 N; 25 mm vs. 19.6 mm and 17.3 mm, respectively; p<0.05). Groups II and III did not differ significantly in this respect (p>0.05).
  
  
  CONCLUSIONS
  Daily administration of single dose LMWH improves tendon healing through increasing the number of fibroblasts and fibrillar collagen synthesis and decreasing mitochondrial degeneration.
authors.affiliation: Gazi Universitesi Tip Fakültesi, Ortopedi ve Travmatoloji Anabilim Dali, Arkara, Turkey. erdinc@gazi.edu.tr
authors.forename: Erdinç
authors.initials: E
authors.lastname: Esen
authors.forename: Erdal
authors.initials: E
authors.lastname: Cila
authors.forename: Candan
authors.initials: C
authors.lastname: Ozoğul
authors.forename: Arzu Gül
authors.initials: AG
authors.lastname: Taşçi
authors.forename: Serkan
authors.initials: S
authors.lastname: Sipahioğlu
authors.forename: Halil Can
authors.initials: HC
authors.lastname: Gemalmaz
authors.forename: Akif Muhtar
authors.initials: AM
authors.lastname: Oztürk
authors.forename: Yunus
authors.initials: Y
authors.lastname: Doğramaci
mesh_terms: D000125:Achilles Tendon / Q000187:drug effects* / Q000502:physiology; D000818:Animals; D004305:Dose-Response Relationship, Drug; D005343:Fibrinolytic Agents / Q000627:therapeutic use; D006495:Heparin, Low-Molecular-Weight / Q000627:therapeutic use*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors; D016896:Treatment Outcome; D014945:Wound Healing / Q000187:drug effects* / Q000502:physiology
chemical_list: D005343:Fibrinolytic Agents; D006495:Heparin, Low-Molecular-Weight