The Effects of Estrogen on Material and Mechanical Properties of the Intra- and Extra-articular Knee Structures

Abstract

Background: Female athletes have a higher incidence of anterior cruciate ligament injuries than do male athletes in similar sports. Hormones, particularly estrogen, have been indicated by some studies to be correlated with the disproportionate number of anterior cruciate ligament injuries in female athletes.

Hypothesis: Estrogen does not affect the mechanical or material properties of primate anterior cruciate ligaments or patellar tendons.

Study Design: Controlled laboratory study.

Methods: Twenty-six cynomolgus monkeys (Macaca fascicularis) were divided into 2 groups: sham operated (estrogen maintained, n = 12) and ovariectomized (estrogen deficient, n = 14). After 2 years, the animals were sacrificed, and various properties of ligaments were tested. Two different ligaments were studied, the anterior cruciate ligament and patellar tendon.

Results: No differences were found between the sham-operated (sham) and ovariectomized group for failure load (anterior cruciate ligament: sham, 394 ± 67 N; ovariectomized, 392 ± 96 N; P > .74), stiffness, elongation at failure, ultimate stress (anterior cruciate ligament: sham, 115 ± 30 MPa; ovariectomized, 128 ± 36 MPa; P > .58), ultimate strain, modulus, failure sites, or energy to failure.

Conclusion: Endogenous estrogen does not directly affect the mechanical or material properties of the anterior cruciate ligament or the patellar tendon of cynomolgus macaques.

Clinical Relevance: This study supports the idea that knee ligament injury in female athletes is not a direct result of estrogen's effect on ligament properties.

Keywords

estrogen biomechanics anterior cruciate ligament (ACL)gender

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References

Agel J

Bershadsky B

Arendt EA

. Hormonal therapy: ACL and ankle injury. Med Sci Sports Exerc. 2006;38:7-12.

Arendt E

Dick R

. Knee injury patterns among men and women in collegiate basketball and soccer: NCAA data and review of literature. Am J Sports Med. 1995;23:694-701.

Arendt EA

Bershadsky B

Agel JA

. Periodicity of non-contact anterior cruciate ligament injuries during the menstrual cycle. J Gend Specif Med. 2002;5:19-26.

Belanger MJ

Moore DC

Crisco JJ III

Fadale PD

Hulstyn MJ

Ehrlich MG

. Knee laxity does not vary with the menstrual cycle, before or after exercise. Am J Sports Med. 2004;32:1150-1157.

Beynnon BD

Bernstein I

Belisle A

, et al. The effect of estradiol and progesterone on knee and ankle laxity. Am J Sports Med. 2005;33: 1298-1304.

Deie M

Sakamaki Y

Sumen Y

Urabe Y

Ikuta Y

. Anterior knee laxity in young women varies with their menstrual cycle. Int Orthop. 2002; 26:154-156.

Goodman AL

Descalzi CD

Johnson DK

Hodgen GD

. Composite pattern of circulating LH, FSH, estradiol, and progesterone during the menstrual cycle in cynomolgus monkeys. Proc Soc Exp Biol Med. 1977;155:479-481.

Gray J

Taunton JE

McKenzie DC

Clement DB

McConkey JP

Davidson RG

. A survey of injuries to the anterior cruciate ligament of the knee in female basketball players. Int J Sports Med. 1985;6:314-316.

Griffin LY

Agel J

Albohm MJ

, et al. Noncontact anterior cruciate ligament injuries: risk factors and prevention strategies. J Am Acad Orthop Surg. 2000;8:141-150.

10.

Heitz NA

Eisenman PA

Beck CL

Walker JA

. Hormonal changes throughout the menstrual cycle and increased anterior cruciate ligament laxity in females. J Athl Train. 1999;34:144-149.

11.

Hewett TE

. Neuromuscular and hormonal factors associated with knee injuries in female athletes: strategies for intervention. Sports Med. 2000;29:313-327.

12.

Hewett TE

Stroupe AL

Nance TA

Noyes FR

. Plyometric training in female athletes: decreased impact forces and increased hamstring torques. Am J Sports Med. 1996;24:765-773.

13.

Huston LJ

Wojtys EM

. Neuromuscular performance characteristics in elite female athletes. Am J Sports Med. 1996;24:427-436.

14.

Hutchinson MR

Ireland ML

. Knee injuries in female athletes.Sports Med. 1995;19:288-302.

15.

Jerome CP

Power RA

Obasanjo IO

, et al. The androgenic anabolic steroid nandrolone decanoate prevents osteopenia and inhibits bone turnover in ovariectomized cynomolgus monkeys.Bone. 1997;20: 355-364.

16.

Karageanes SJ

Blackburn K

Vangelos ZA

. The association of the menstrual cycle with the laxity of the anterior cruciate ligament in adolescent female athletes.Clin J Sport Med. 2000;10:162-168.

17.

Lane JM

Russell L

Khan SN

. Osteoporosis.Clin Orthop Relat Res. 2000;372:139-150.

18.

LaPrade RF

Bollom TS

Wentorf FA

Wills NJ

Meister K

. Mechanical properties of the posterolateral structures of the knee.Am J Sports Med. 2005;33:1386-1391.

19.

Lindenfeld TN

Schmitt OJ

Herdy MP

. Incidence of injury in outdoor soccer.Am J Sports Med. 1994;22:364-371.

20.

Liu SH

Al-Shaikh R

Panossian V

. Primary immunolocalization of estrogen and progesterone target cells in the human anterior cruciate ligament.J Orthop Res. 1996;14:526-533.

21.

Liu SH

Al-Shaikh RA

Panossian V

Finerman GA

Lane JM

. Estrogen affects the cellular metabolism of the anterior cruciate ligament: a potential explanation for female athletic injury.Am J Sports Med. 1997;25:704-709.

22.

Liu SH

Yang RS

al-Shaikh R

Lane JM

. Collagen in tendon, ligament, and bone healing: a current review.Clin Orthop Relat Res. 1995;318: 265-278.

23.

Moller-Nielsen J

Hammar M

. Women's soccer injuries in relation to the menstrual cycle and oral contraceptive use.Med Sci Sports Exerc. 1989;21:126-129.

24.

More RC

Karras BT

Neiman R

Fritschy D

Woo SL

Daniel DM

. Hamstrings: an anterior cruciate ligament protagonist. An in vitro study.Am J Sports Med. 1993;21:231-237.

25.

Myklebust G

Maehlum S

Holm I

Bahr R

. A prospective cohort study of anterior cruciate ligament injuries in elite Norwegian team handball.Scand J Med Sci Sports. 1998;8:149-153.

26.

Obasanjo IO

Clarkson TB

Weaver DS

. Effects of the anabolic steroid nandrolone decanoate on plasma lipids and coronary arteries of female cynomolgus macaques.Metabolism. 1996;45:463-468.

27.

Posthuma BW

Bass MJ

Bull SB

Nisker JA

. Detecting changes in functional ability in women with premenstrual syndrome.Am J Obstet Gynecol. 1987;156:275-278.

28.

Rau MD

Renouf D

Benfield D

, et al. Examination of the failure properties of the anterior cruciate ligament during the estrous cycle.Knee. 2005;12:37-40.

29.

Sciore P

Frank CB

Hart DA

. Identification of sex hormone receptors in human and rabbit ligaments of the knee by reverse transcription-polymerase chain reaction: evidence that receptors are present in tissue from both male and female subjects.J Orthop Res. 1998;16:604-610.

30.

Shultz SJ

Sander TC

Kirk SE

Perrin DH

. Sex differences in knee laxity change across the female menstrual cycle.J Sports Med Phys Fitness. 2005;45:594-603.

31.

Slauterbeck J

Clevenger C

Lundberg W

Burchfield DM

. Estrogen level alters the failure load of the rabbit anterior cruciate ligament.J Orthop Res. 1999;17:405-408.

32.

Slauterbeck JR

Fuzie SF

Smith MP

, et al. The menstrual cycle, sex hormones, and anterior cruciate ligament injury.J Athl Train. 2002;37: 275-280.

33.

Strickland SM

Belknap TW

Levine RE

, et al. Lack of hormonal influences on mechanical properties of sheep knee ligaments.Trans Orthop Res Soc. 2000;25:21-21.

34.

Taechakraichana N

Limpaphayom K

Ninlagorn T

. A randomized trial of oral contraceptive and hormone replacement therapy on bone mineral density and coronary heart disease risk factors in post menopausal women.Obstet Gynecol. 2000;95:87-94.

35.

Teitz CC

Hu SS

Arendt EA

. The female athlete: evaluation and treatment of sports-related problems.J Am Acad Orthop Surg. 1997;5:87-96.

36.

Wojtys EM

Huston LJ

Boynton MD

Spindler KP

Lindenfeld TN

. The effect of the menstrual cycle on anterior cruciate ligament injuries in women as determined by hormone levels.Am J Sports Med. 2002;30: 182-188.