Parecoxib impairs early tendon repair but improves later remodeling.
BACKGROUND
Cyclooxygenase-2 inhibitors inhibit bone repair.


OBJECTIVE
Cyclooxygenase inhibitors might also have a negative effect on early tendon repair, although a positive effect on late tendon repair previously has been shown.


METHODS
Controlled laboratory study.


METHODS
Achilles tendon transection was performed on 80 rats. Sixty rats were given daily intramuscular injections of either parecoxib (6.4 mg/kg body weight) or saline for the first 5 days after surgery and sacrificed either at 8 or 14 days. The remaining 20 rats were given intramuscular parecoxib or saline injections from day 6 until sacrifice at 14 days.


RESULTS
At 8 days, early parecoxib treatment caused a 27% decrease in force at failure (P = .007), a 25% decrease in maximum stress (P = .01), and a 31% decrease in energy uptake (P = .05). Stiffness and transverse area were not significantly affected. At 14 days, early parecoxib treatment caused a decrease in stiffness (P = .004). In contrast to early treatment, late parecoxib treatment caused a 16% decrease in cross-sectional area (P = .03) and a 29% increase in maximum stress (P = .04).


CONCLUSIONS
During early tendon repair, a cyclooxygenase-2 inhibitor had a detrimental effect. During remodelling, however, inflammation appears to have a negative influence, and cyclooxygenase-2 inhibitors might be of value.


CONCLUSIONS
The results suggest that cyclooxygenase-2 inhibitors should be used with care in the early period after tendon injury.
Virchenko
Olena
O
Section for Orthopaedics and Sports Medicine, Department of Neuroscience and Locomotion, Faculty of Health Sciences, Linköping, Sweden.
Skoglund
Björn
B
Aspenberg
Per
P
D000125:Achilles Tendon / Q000187:drug effects / Q000254:growth & development* / Q000293:injuries*; D000818:Animals; D001696:Biomechanical Phenomena; D016861:Cyclooxygenase Inhibitors / Q000009:adverse effects* / Q000494:pharmacology* / Q000627:therapeutic use; D005260:Female; D007273:Injections, Intramuscular; D007555:Isoxazoles / Q000009:adverse effects* / Q000494:pharmacology* / Q000627:therapeutic use; D019637:Orthopedic Procedures; D051381:Rats; D017207:Rats, Sprague-Dawley; D013708:Tendon Injuries / Q000534:rehabilitation / Q000601:surgery*; D016474:Weight-Bearing
D016861:Cyclooxygenase Inhibitors; D007555:Isoxazoles; C409945:parecoxib