Relationship Between Anterior Knee Laxity and General Joint Laxity During the Menstrual Cycle.

BACKGROUND

Anterior cruciate ligament (ACL) injury has been reported to have a higher incidence in women than in men.

PURPOSE/HYPOTHESIS

The purpose was to examine the relationship of anterior knee laxity (AKL), stiffness, and generalized joint laxity (GJL) with respect to the menstrual cycle. It was hypothesized that AKL and GJL would increase during the ovulation phase, when estrogen levels are high.

STUDY DESIGN

Descriptive laboratory study.

METHODS

A total of 15 female university students aged >20 years and with normal menstrual cycles were evaluated. AKL was measured as anterior tibial displacement of the femur after application of 44-, 89-, and 133-N loads to the tibia. Stiffness was calculated as Δ force/Δ displacement at loads between 44 and 89 N and between 89 and 133 N. The University of Tokyo joint laxity test was used for evaluation of GJL. The participants' menstrual cycle was divided into the early follicular, late follicular, ovulation, and luteal phases using the basal body temperature method and an ovulation kit; AKL and GJL were measured once during each phase. Participants were also stratified according to the presence or absence of genu recurvatum (GR).

RESULTS

There was no significant difference in AKL, stiffness, or GJL among the menstrual phases. In the GR group, AKL values at 89 N and 133 N were significantly higher in the ovulation phase than in the early follicular phase (

CONCLUSION

Women with GR may have increased AKL in the ovulation phase when compared with the early follicular phase, which may be a risk factor for ACL injury.

CLINICAL RELEVANCE

The results of this study suggest that the ovulation phase may be related to the greater incidence of ACL injuries in women.

Informations de copyright

© The Author(s) 2021.

Déclaration de conflit d'intérêts

One or more of the authors has declared the following potential conflict of interest or source of funding: This study was supported by a Grant-in-Aid for Scientific Research (19K11358) from the Japan Society for the Promotion of Science (JSPS) and commissioned by the Japan Sports Agency (Female Athletes Development and Support Projects 2020). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.