When Women Present with Musculoskeletal Pain, Assess Hormonal Factors

LAS VEGAS—Anatomic variability in women predisposes them to specific musculoskeletal conditions, which differ during life stages. Rehabilitation strategies to treat muscular imbalance and core weakness can be highly effective in all musculoskeletal conditions. That's the conclusion of a Wednesday session, titled “Musculoskeletal Pain in Women,” which focused on differences in pain presentation in adolescence, childbearing years, and mid-late life and on rehabilitation treatment options for common musculoskeletal conditions.

“There are important differences between the sexes for many clinical pain disorders which may be explained, at least in part, by hormonal mechanisms,” said Colleen M. Fitzgerald, MD, MS, Associate Professor in the Department of Obstetrics and Gynecology & PM&R, Division of Female Pelvic Medicine and Reconstructive Surgery, Loyola University Chicago Stritch School of Medicine, Chicago, Illinois.

“Therefore, assessment of hormonal factors may be important in both evaluating and researching pain conditions in women. Many pain conditions are associated with menstrual cycle-related fluctuations in pain complaints.” Hormonal effects on female physiology relate to strength, neuromuscular control, aerobic capacity, lean body mass, bone mineral density, and joint hypermobility. Exogenous hormone use, at least in the formulations of hormone replacement therapy previously in widespread use, appears to increase the risk of certain pain disorders, she added.

Musculoskeletal conditions that can affect women include those of the lower extremity (patellofemoral pain, anterior cruciate ligament injury, and stress fracture), upper extremity (shoulder), and spine/pelvis. Extrinsic risk factors for stress fractures, for example, include osteoporosis, menstrual dysfunction, poor nutrition, eating disorders, strength, flexibility, and limb length.

Prepuberty, girls have muscle strength equal to boys, similar neuromuscular control about the hip and knee, and equal peak hamstring and quad torque, knee stiffness, and maximum keen valgum during landing from a jump, Dr. Fitzgerald noted. At puberty between the ages of 9 through 12, release of estrogen results in stronger bones in girls, while testosterone produces stronger muscles in boys. Neuromuscularly, girls have less dynamic hip and knee stability during landing and pivoting, increased knee valgum, decreased hip control, greater hip adduction, and greater hip internal rotation following puberty.

These pelvic and lower extremity structural differences predispose young women to certain injuries; specifically knee injuries such as patellofemoral syndrome and lower extremity injuries, including anterior cruciate ligament injury. Bone health, stress fractures, and the high prevalence of urinary stress incontinence in young girls highlights that continence mechanisms is a musculoskeletal issue, even in women who have not yet had children.

Girls who are particularly athletic are an increased risk for stress fractures as they may have amenorrhea caused by caloric restriction, excessive exercise, low body fat, emotional stress, or genetic profile. Others may present with the female athlete triad, a combination of disordered eating, amenorrhea, and osteoporosis.

During childbearing years, biomechanical, hormonal, and anatomical changes occur. Pregnancy, labor, and delivery all inherently disrupt the core musculature, causing differing pain presentations, such as pelvic girdle pain, delivery-induced pelvic floor myofascial pain, and diastasis rectus abdominous, which can affect posture, pelvic joint stability, spinal motions, respiration, and elimination. In middle age and later life, women are more likely to have osteoarthritis, osteoporosis-related fractures, and tendonitis/bursitis, and have various causes of low back pain.

Dr. Fitzgerald discussed realistic treatment options for a woman with the variant musculoskeletal conditions that predominate in each phase of her lifespan. For example, to prevent knee injuries, extrinsic conditioning training and prevention programs may emphasize balance, stretching, plyometrics, positioning education, and strengthening of the hamstring, glut medius, and hip abductor muscles.

Exercise-associated urinary incontinence is caused by an excessive rise in intraabdominal pressure that overwhelms normal continence mechanisms. Women with a diagnosis of stress urinary incontinence related to exercise may wish to change the exercise technique, stop the activity, or wear a pad.

During pregnancy, women may use manual therapy and self-mobilization to promote postural alignment and symmetrical body mechanics (ie, no bending or twisting). Finally, regardless of age, all women may benefit from Tai Chi and strength training exercises that include lumbar stabilization.