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Common Musculoskeletal Disorders in Women

      Women are prone to certain orthopedic conditions and may present to their primary care physician for treatment. An appreciation of the physiological and anatomical differences between women and men and the musculoskeletal conditions that commonly affect active women can aid the physician in diagnosis and treatment. We discuss common musculoskeletal conditions of active women including those affecting the low back, knee, shoulder, and foot. We also discuss common stress fractures seen in women. Various treatment and prevention strategies are reviewed and include physical therapy, bracing, medications, and surgery.
      In 1996, 37.1 million people, 55% of whom were women, presented to outpatient clinics with new orthopedic conditions.
      Differences in the documented injury rates of men and women may be at least partially due to differences between the sexes in symptom reporting.
      • Almeida SA
      • Trone DW
      • Leone DM
      • Shaffer RA
      • Patheal SL
      • Long K
      Gender differences in musculoskeletal injury rates: a function of symptom reporting?.
      However, there are other contributing factors. Women not only make up a larger proportion of the US population but also are participating in athletics in ever-growing numbers. Differences in physiology between men and women, including hormonal effects on the connective tissues and decreased total muscle cross-sectional area, may play a role.
      • Knapik JJ
      • Sharp MA
      • Canham-Chervak M
      • Hauret K
      • Patton JF
      • Jones BH
      Risk factors for training-related injuries among men and women in basic combat training.
      • Bell NS
      • Mangione TW
      • Hemenway D
      • Amoroso PJ
      • Jones BH
      High injury rates among female army trainees: a function of gender?.
      Also, anatomical differences in women, such as the wider pelvis as well as their increased valgus angulation at the knee and increased foot pronation, may increase their risk of injury of the lower extremity.
      • Knapik JJ
      • Sharp MA
      • Canham-Chervak M
      • Hauret K
      • Patton JF
      • Jones BH
      Risk factors for training-related injuries among men and women in basic combat training.
      • Bell NS
      • Mangione TW
      • Hemenway D
      • Amoroso PJ
      • Jones BH
      High injury rates among female army trainees: a function of gender?.
      • Kowal DM
      Nature and causes of injuries in women resulting from an endurance training program.
      In general, men and women with similar orthopedic injuries should be treated similarly. However, many musculoskeletal injuries are seen more frequently in women or are in some way unique to women. This article discusses musculoskeletal disorders seen commonly in active women.

      EPIDEMIOLOGICAL CONSIDERATIONS

      Women make up a large proportion of the aging population in the United States because their life span averages 7 years longer than that of men. Furthermore, women are affected more commonly by certain widespread orthopedic conditions such as osteoarthritis and osteoporosis. Also, women have been increasingly active in athletic endeavors. Since enactment of Title IX of the Education Amendments of 1972, which mandated that all educational institutions receiving federal funds provide equal athletic opportunities to men and women, female participation in high school athletics has increased by more than 700%,
      with 1 in 3 high school girls participating in varsity sports in 1998.
      Similar trends have been observed in collegiate and elitelevel sports.
      Numerous benefits have been attributed to athletic participation. Studies have shown lower rates of teenage pregnancy, depression, and cigarette smoking, along with increased self-esteem and higher rates of high school and college graduation in young female athletes compared with nonathletes.
      • Asci FH
      • Kosar SN
      • Isler AK
      The relationship of self-concept and perceived athletic competence to physical activity level and gender among Turkish early adolescents.
      Women who participate in sports also have decreased risk of obesity, coronary artery disease, hypertension, diabetes, colon cancer, and osteoporosis.
      • Ford MA
      • Bass MA
      • Turner LW
      • Mauromoustakos A
      • Graves BS
      Past and recent physical activity and bone mineral density in college-aged women.
      • Warren MP
      • Stiehl AL
      Exercise and female adolescents: effects on the reproductive and skeletal systems.
      • Tanji JL
      The benefits of exercise for women.
      • Marti B
      Health effects of recreational running in women: some epidemiological and preventive aspects.
      • Hu FB
      • Sigal RJ
      • Rich-Edwards JW
      • et al.
      Walking compared with vigorous physical activity and risk of type 2 diabetes in women: a prospective study.
      • Asikainen TM
      • Kukkonen-Harjula K
      • Miilunpalo S
      Exercise for health for early postmenopausal women: a systematic review of randomised controlled trials.
      • Meyer NL
      • Shaw JM
      • Manore MM
      • et al.
      Bone mineral density of olympic-level female winter sport athletes.
      However, the increase in female athletic participation has likely contributed to an increased incidence of injury. Although most musculoskeletal injuries sustained during sporting activities are sports-specific rather than sex-specific, women appear to be more prone to spondylolisthesis, anterior cruciate ligament (ACL) injuries, patellofemoral pain, and stress fractures of the pelvis and hip.
      • Sallis RE
      • Jones K
      • Sunshine S
      • Smith G
      • Simon L
      Comparing sports injuries in men and women.
      • Ireland ML
      • Ott SM
      Special concerns of the female athlete.
      Women who participate in athletics are more likely to experience repetitive overuse injuries and microtrauma
      and are at high risk of having an abnormal eating behavior that may lead to amenorrhea and osteoporosis, a constellation of conditions known as the female athlete triad.
      • Ireland ML
      • Ott SM
      Special concerns of the female athlete.
      • Wiggins DL
      • Wiggins ME
      The female athlete.
      • Gibson JH
      • Mitchell A
      • Harries MG
      • Reeve J
      Nutritional and exercise-related determinants of bone density in elite female runners.
      • Timmerman MG
      Medical problems of adolescent female athletes.
      • Beals KA
      • Manore MM
      Disorders of the female athlete triad among collegiate athletes.
      • Lantz CD
      • Rhea DJ
      • Mesnier K
      Eating attitudes, exercise identity, and body alienation in competitive ultramarathoners.
      • Hinton PS
      • Sanford TC
      • Davidson MM
      • Yakushko OF
      • Beck NC
      Nutrient intakes and dietary behaviors of male and female collegiate athletes.

      OSTEOPOROSIS

      As defined by the World Health Organization, osteoporosis represents a bone mineral density of 2.5 SD or more below the young adult mean. This condition occurs 4 times more frequently in women than in men. Approximately 30% of postmenopausal Caucasian women in the United States have osteoporosis at any given time, and half of postmenopausal Caucasian women will experience an osteoporotic fracture during their lives.
      • Lenchik L
      • Sartoris DJ
      Current concepts in osteoporosis.
      The most common sites of fracture are the vertebrae, hip, wrist, and proximal humerus.
      • Lenchik L
      • Sartoris DJ
      Current concepts in osteoporosis.
      • Riggs BL
      • Melton III, LJ
      The worldwide problem of osteoporosis: insights afforded by epidemiology.
      The economic burden of osteoporosis in the United States exceeds $10 billion per year,
      • Lenchik L
      • Sartoris DJ
      Current concepts in osteoporosis.
      and with the aging population, this cost is likely to increase. Hospitalization for hip fracture among women aged 65 years and older increased 23% from 1988 to 1996.
      • Stevens JA
      • Olson S
      Reducing falls and resulting hip fractures among older women.
      In women older than 75 years, the most commonly performed surgical procedure is for osteoporotic hip fracture.
      Up to 20% of these patients die within 1 year of their injury, and up to 70% do not return to their preinjury functional capacity.
      • Lenchik L
      • Sartoris DJ
      Current concepts in osteoporosis.
      • Stevens JA
      • Olson S
      Reducing falls and resulting hip fractures among older women.
      Among the many risk factors for osteoporosis are advancing age, female sex, white or Asian ethnicity, and various endocrine conditions (amenorrhea, hyperthyroidism, hyperparathyroidism, hypercortisolism, and hypergonadism). Peak bone mass usually is reached between ages 18 and 25 years, with 92% of total body mineral content typically achieved before age 18 years.
      • Wiggins DL
      • Wiggins ME
      The female athlete.
      • Weaver CM
      • Teegarden D
      • Lyle RM
      • et al.
      Impact of exercise on bone health and contraindication of oral contraceptive use in young women.
      Preventive treatment of osteoporosis includes maintaining adequate calcium intake from a young age and participating in regular weight-bearing exercise.
      • Ford MA
      • Bass MA
      • Turner LW
      • Mauromoustakos A
      • Graves BS
      Past and recent physical activity and bone mineral density in college-aged women.
      • Marti B
      Health effects of recreational running in women: some epidemiological and preventive aspects.
      • Meyer NL
      • Shaw JM
      • Manore MM
      • et al.
      Bone mineral density of olympic-level female winter sport athletes.
      • Yamazaki S
      • Ichimura S
      • Iwamoto J
      • Takeda T
      • Toyama Y
      Effect of walking exercise on bone metabolism in postmenopausal women with osteopenia/osteoporosis.
      • Winters-Stone KM
      • Snow CM
      One year of oral calcium supplementation maintains cortical bone density in young adult female distance runners.
      All patients should be encouraged to limit use of tobacco and alcohol. The older population should be instructed in fall prevention including avoidance of uneven surfaces, removal of area rugs from living quarters, and use of gait aids as necessary.
      • Stevens JA
      • Olson S
      Reducing falls and resulting hip fractures among older women.
      Medical treatment of osteoporosis may include estrogen, bis-phosphonates, and calcitonin.
      • Wiggins DL
      • Wiggins ME
      The female athlete.
      • Lenchik L
      • Sartoris DJ
      Current concepts in osteoporosis.
      • Riggs BL
      • Melton III, LJ
      The worldwide problem of osteoporosis: insights afforded by epidemiology.
      • American Academy of Pediatrics Committee on Sports Medicine and Fitness
      Medical concerns in the female athlete.
      Estrogen replacement therapy reportedly increases bone mineral density in the spine and hip; however, its use is controversial because of the potential association with breast cancer and heart disease.
      • Lenchik L
      • Sartoris DJ
      Current concepts in osteoporosis.
      Bisphosphonates suppress osteoclastic activity leading to decreased bone resorption and have been shown to increase bone mineral density in the spine and hip.
      • Lenchik L
      • Sartoris DJ
      Current concepts in osteoporosis.
      • Riggs BL
      • Melton III, LJ
      The worldwide problem of osteoporosis: insights afforded by epidemiology.
      Calcitonin also inhibits osteoclast activity and has been shown to modestly increase bone mineral density in the spine.
      • Lenchik L
      • Sartoris DJ
      Current concepts in osteoporosis.
      Osteoporosis in young women may be part of the female athlete triad.
      • Marti B
      Health effects of recreational running in women: some epidemiological and preventive aspects.
      • Wiggins DL
      • Wiggins ME
      The female athlete.
      • Beals KA
      • Manore MM
      Disorders of the female athlete triad among collegiate athletes.
      • Hinton PS
      • Sanford TC
      • Davidson MM
      • Yakushko OF
      • Beck NC
      Nutrient intakes and dietary behaviors of male and female collegiate athletes.
      Loss of bone density in these young women may be irreversible and may lead to increased risk of osteoporotic fractures in the future. Of note, amenorrhea is not considered a normal consequence of exercise, and a thorough medical evaluation should ensue for any premenopausal patient with this condition. Those with functional hypothalamic amenorrhea should receive estrogen replacement therapy as well as calcium and vitamin D supplementation.
      • Wiggins DL
      • Wiggins ME
      The female athlete.
      • Gibson JH
      • Mitchell A
      • Harries MG
      • Reeve J
      Nutritional and exercise-related determinants of bone density in elite female runners.
      A multidisciplinary approach that includes specialists in nutrition, psychology, and endocrinology should be used in treating eating disorders.
      • Marti B
      Health effects of recreational running in women: some epidemiological and preventive aspects.
      • Beals KA
      • Manore MM
      Disorders of the female athlete triad among collegiate athletes.
      • Hinton PS
      • Sanford TC
      • Davidson MM
      • Yakushko OF
      • Beck NC
      Nutrient intakes and dietary behaviors of male and female collegiate athletes.

      SPINE DISORDERS

      Low back pain in active female athletes is commonly due to muscular strain. However, other potential causes of pain must be considered. A defect in the pars interarticularis (spondylolysis) may account for 47% of back pain in adolescence.
      • Micheli LJ
      • Wood R
      Back pain in young athletes: significant differences from adults in causes and patterns.
      Female athletes who repetitively load the spine in hyperextension, such as gymnasts, divers, figure skaters, and dancers, are at higher risk than the general population.
      • Omey ML
      • Micheli LJ
      • Gerbino II, PG
      Idiopathic scoliosis and spondylolysis in the female athlete: tips for treatment.
      Patients with spondylolytic low back pain define their pain as a dull aching that frequently is made worse with hyperextension. The pain is localized usually to the L4 or L5 region and may radiate to the buttocks but rarely has an associated radicular component. Physical examination should include range of motion of the spine, and a thorough neurologic examination should be performed. Pain with hyperextension and hamstring tightness may be elicited. Radiological evaluation should begin with anteroposterior, lateral, and, most importantly, oblique views of the lumbosacral spine. Flexion and extension views may help rule out spondylolisthesis, a condition of slippage of the involved vertebral body anteriorly with respect to the caudal adjacent vertebra. A bone scan or computed tomogram may be necessary to rule out a subtle pars interarticularis defect.
      Conservative treatment generally consists of rest from the offensive activity with bracing in the acute setting and a lumbar stabilization program in the more chronic setting. Treatment typically involves exercises to strengthen the trunk or “core” musculature. Patients are able to return to their usual activities when asymptomatic. Surgery is rarely necessary and generally is reserved for patients with notable spondylolisthesis, progressive neurologic deficits, or intractable symptoms despite conservative measures.
      • Omey ML
      • Micheli LJ
      • Gerbino II, PG
      Idiopathic scoliosis and spondylolysis in the female athlete: tips for treatment.
      • Lonstein JI
      Spondylolysis and spondylolisthesis.
      • d'Hemecourt PA
      • Gerbino II, PG
      • Micheli LJ
      Back injuries in the young athlete.
      Adolescent idiopathic scoliosis is more common in female patients and is generally asymptomatic. The presence of pain merits further work-up to rule out any underlying pathology such as spondylolysis, syringomyelia, tethered cord syndrome, tumor, or disk herniation. The patient's age and level of skeletal maturation, the size of the curve, and the progression of the curve predicate treatment of adolescent idiopathic scoliosis. Progressive curves in skeletally immature children generally are treated with bracing. Growing children with curves greater than 40° and skeletally mature patients with curves greater than 50° to 60° are considered for surgery.
      • Sallis RE
      • Jones K
      • Sunshine S
      • Smith G
      • Simon L
      Comparing sports injuries in men and women.
      • Omey ML
      • Micheli LJ
      • Gerbino II, PG
      Idiopathic scoliosis and spondylolysis in the female athlete: tips for treatment.
      • Tolo VT
      Surgical treatment of adolescent idiopathic scoliosis.
      In an elderly woman who presents with acute onset of back pain, an osteoporotic compression fracture is likely; plain radiographs show loss of vertebral body height. The fractures generally are treated conservatively with activity modification, external bracing for comfort, and analgesia. Vertebroplasty (injection of polymethylmethacrylate into the vertebral body) may relieve pain but does not necessarily restore vertebral body height.
      • Alvarez L
      • Perez-Higueras A
      • Granizo JJ
      • de Miguel I
      • Quinones D
      • Rossi RE
      Predictors of outcomes of percutaneous vertebroplasty for osteoporotic vertebral fractures.
      • Liliang PC
      • Su TM
      • Liang CL
      • Chen HJ
      • Tsai YD
      • Lu K
      Percutaneous vertebroplasty improves pain and physical functioning in elderly osteoporotic vertebral compression fracture patients.
      • McKiernan F
      • Faciszewski T
      • Jensen R
      Quality of life following vertebroplasty.
      • Ohlin A
      • Johnell O
      Vertebroplasty and kyphoplasty in the fractured osteoporotic spine.
      If the etiology of low back pain is determined to be muscular strain, treatment involves use of ice in the acute phase, followed by heat and massage to decrease secondary muscle spasm. Tight hamstrings, weak abdominal and paraspinal musculature, and lack of flexibility of the lumbosacral spine should be addressed with appropriate stretching and strengthening exercises.
      • d'Hemecourt PA
      • Gerbino II, PG
      • Micheli LJ
      Back injuries in the young athlete.

      DISORDERS OF THE KNEE

      Compared with men, active women more commonly experience patellofemoral pain and disruptions of the ACL. This increased incidence may be due to anatomical and physiological differences between men and women. An understanding of these differences may help guide treatment and prevention.
      • Sallis RE
      • Jones K
      • Sunshine S
      • Smith G
      • Simon L
      Comparing sports injuries in men and women.
      • Ireland ML
      • Ott SM
      Special concerns of the female athlete.
      • Ford KR
      • Myer GD
      • Toms HE
      • Hewett TE
      Gender differences in the kinematics of unanticipated cutting in young athletes.
      • Hass CJ
      • Schick EA
      • Tillman MD
      • Chow JW
      • Brunt D
      • Cauraugh JH
      Knee biomechanics during landings: comparison of pre- and postpubescent females.
      • Bergstrom KA
      • Brandseth K
      • Fretheim S
      • Tvilde K
      • Ekeland A
      Activity-related knee injuries and pain in athletic adolescents.
      The patellofemoral joint bears up to 7 times body weight with squatting and jogging and 50% of body weight with walking. Abnormal alignment of the knee extensor mechanism can increase stress at the patellofemoral articulation and contribute to softening of the articular cartilage and associated pain and inflammation.
      The Q angle is the angle formed by the intersection of the axis of the quadriceps extensor mechanism and the axis of the patellar tendon. An increased Q angle may lead to increased lateral subluxation forces and increased pressure on the lateral facet of the patella. Factors that contribute to an increased Q angle in women include a wider pelvis, increased femoral anteversion, increased knee valgus, external tibial torsion, increased ligamentous laxity, and hyperpronation of the foot.
      • Bergstrom KA
      • Brandseth K
      • Fretheim S
      • Tvilde K
      • Ekeland A
      Activity-related knee injuries and pain in athletic adolescents.
      • Livingston LA
      The quadriceps angle: a review of the literature.
      In addition, patella alta, a tight lateral patellar retinaculum, and a hypoplastic or weak vastus medialis obliquus can contribute to patellofemoral maltracking. The combination of increased femoral anteversion, external tibial torsion, and hyperpronation of the foot is often termed the miserable malalignment syndrome and is seen more commonly in women. Treatment of patellofemoral pain is aimed at relieving discomfort and addressing patellar maltracking. First-line treatment includes rest, use of ice, and judicial use of nonsteroidal anti-inflammatory medications. Patients also should begin a rehabilitation program aimed at strengthening the quadriceps and, in particular, the vastus medialis obliquus. Medially directed patellar mobilization may be indicated in patients exhibiting a tight lateral retinaculum. Stretching of the iliotibial band, hamstrings, and gastrocnemius/soleus complex may decrease forces across the patellofemoral joint. Finally, hip abductor strengthening may decrease lateral tilt of the pelvis during single-leg stance and thus decrease valgus force at the knee.
      Orthotics and braces often are used. Orthotics with medial longitudinal arch support frequently limit hyperpronation and thus decrease valgus forces at the knee.
      • Johnston LB
      • Gross MT
      Effects of foot orthoses on quality of life for individuals with patellofemoral pain syndrome.
      Knee sleeves with a patellar cutout may decrease pain and may improve stabilization of the patella within the femoral groove. Taping to improve patellar tracking and decrease patellar tilt can help the patient temporarily to participate in athletic events in conjunction with a formal rehabilitation program. Surgery is rarely necessary for patellofemoral pain. Realignment procedures are used occasionally for severe patellar maltracking problems refractory to nonoperative management.
      Athletic women participating in noncontact sports have an increased incidence of ACL disruption compared with men participating in the same activities.
      • Ford KR
      • Myer GD
      • Toms HE
      • Hewett TE
      Gender differences in the kinematics of unanticipated cutting in young athletes.
      • Baker MM
      Anterior cruciate ligament injuries in the female athlete.
      • Ferrari JD
      • Bach Jr, BR
      • Bush-Joseph CA
      • Wang T
      • Bojchuk J
      Anterior cruciate ligament reconstruction in men and women: an outcome analysis comparing gender.
      • Gwinn DE
      • Wilckens JH
      • McDevitt ER
      • Ross G
      • Kao TC
      The relative incidence of anterior cruciate ligament injury in men and women at the United States Naval Academy.
      For example, female soccer players are more than twice as likely to experience ACL injuries than are male soccer players.
      • Gwinn DE
      • Wilckens JH
      • McDevitt ER
      • Ross G
      • Kao TC
      The relative incidence of anterior cruciate ligament injury in men and women at the United States Naval Academy.
      • Arendt E
      • Dick R
      Knee injury patterns among men and women in collegiate basketball and soccer: NCAA data and review of literature.
      In basketball, the injury rate is more than 3 times higher in women.
      • Gwinn DE
      • Wilckens JH
      • McDevitt ER
      • Ross G
      • Kao TC
      The relative incidence of anterior cruciate ligament injury in men and women at the United States Naval Academy.
      • Arendt E
      • Dick R
      Knee injury patterns among men and women in collegiate basketball and soccer: NCAA data and review of literature.
      The mechanism of injury is usually a cutting movement, a sudden deceleration, or landing from a jump. Various extrinsic and intrinsic risk factors have been implicated.
      • Ford KR
      • Myer GD
      • Toms HE
      • Hewett TE
      Gender differences in the kinematics of unanticipated cutting in young athletes.
      • Arendt E
      • Dick R
      Knee injury patterns among men and women in collegiate basketball and soccer: NCAA data and review of literature.
      • Toth AP
      • Cordasco FA
      Anterior cruciate ligament injuries in the female athlete.
      • Loudon JK
      • Jenkins W
      • Loudon KL
      The relationship between static posture and ACL injury in female athletes.
      Extrinsic factors include lower levels of skill and experience as well as differences in muscle strength, endurance, and muscle recruitment.
      • Ford KR
      • Myer GD
      • Toms HE
      • Hewett TE
      Gender differences in the kinematics of unanticipated cutting in young athletes.
      • Baker MM
      Anterior cruciate ligament injuries in the female athlete.
      • Loudon JK
      • Jenkins W
      • Loudon KL
      The relationship between static posture and ACL injury in female athletes.
      • Gilchrist J
      • Jones BH
      • Sleet DA
      • Kimsey CD
      Exercise-related injuries among women: strategies for prevention from civilian and military studies.
      Intrinsic factors include anatomical and hormonal differences between men and women. In addition to differences in lower extremity alignment, women, on average, have a narrower femoral intercondylar notch. Some have argued that a woman's smaller intercondylar notch may lead to impingement of the ACL within the notch. Others have proposed that a smaller notch may contain a smaller and therefore weaker ACL. Several studies have postulated a hormonal role in ACL injuries because estrogen and progesterone receptors have been shown to be present within the ACL. Estradiol has been shown to reduce fibroblast proliferation and collagen synthesis in vitro.
      Studies also have linked ACL injury to certain phases of the menstrual cycle.
      • Arendt EA
      • Bershadsky B
      • Agel J
      Periodicity of noncontact anterior cruciate ligament injuries during the menstrual cycle.
      Treatment of ACL injuries involves rehabilitation in the acute setting to restore range of motion, strength, and proprioception (joint position sense). Functional bracing may be considered; however, data are lacking regarding the efficacy of bracing for prevention of further injury. Less active patients who do not participate in jumping, cutting, twisting, or pivoting activities may function well with nonoperative treatment. Active women involved with sports or other activities that require jumping, cutting, or pivoting are offered surgery to improve stability and to decrease the risk of subsequent meniscal tears or osteochondral injuries. Investigations show that outcomes after surgery are equally successful in male and female patients, indicating that sex should not be a factor when considering a patient as a candidate for surgical management of ACL injury.
      • Ferrari JD
      • Bach Jr, BR
      • Bush-Joseph CA
      • Wang T
      • Bojchuk J
      Anterior cruciate ligament reconstruction in men and women: an outcome analysis comparing gender.
      Prevention of ACL injuries may include improving skill level, muscle-reaction time, and quadriceps and hamstring strength.
      • Gilchrist J
      • Jones BH
      • Sleet DA
      • Kimsey CD
      Exercise-related injuries among women: strategies for prevention from civilian and military studies.
      • Irmischer BS
      • Harris C
      • Pfeiffer RP
      • DeBeliso MA
      • Adams KJ
      • Shea KG
      Effects of a knee ligament injury prevention exercise program on impact forces in women.
      Plyometric exercises and agility training programs with emphasis on educating women about proper jumping, landing, and pivoting techniques have been shown to decrease the risk of ACL injuries.
      • Irmischer BS
      • Harris C
      • Pfeiffer RP
      • DeBeliso MA
      • Adams KJ
      • Shea KG
      Effects of a knee ligament injury prevention exercise program on impact forces in women.
      • Paterno MV
      • Myer GD
      • Ford KR
      • Hewett TE
      Neuromuscular training improves single-limb stability in young female athletes.
      Prophylactic bracing has not been shown to prevent ACL injuries.
      • Tyler TF
      • McHugh MP
      Neuromuscular rehabilitation of a female Olympic ice hockey player following anterior cruciate ligament reconstruction.

      SHOULDER

      Shoulder problems commonly seen in women include impingement syndrome, rotator cuff tendinitis, instability, thoracic outlet syndrome, and adhesive capsulitis (frozen shoulder syndrome).
      Impingement of the anterior cuff and biceps tendon on the inferior surface of the acromion may cause irritation and lead to rotator cuff tendonitis or rotator cuff tears. This is seen more commonly in older women. Risk factors include degenerative changes at the acromioclavicular joint and congenital anomalies of the acromion leading to a relative decrease in the subacromial space. Treatment of these disorders initially consists of activity modification, application of ice, and nonsteroidal anti-inflammatory medications. Patients may benefit sometimes from a subacromial corticosteroid injection to decrease inflammation. Occasionally, surgical treatment in the form of a subacromial decompression is used to increase the subacromial space and decrease impingement. In younger patients, increased laxity of the shoulder often contributes to impingement. In these patients, a shoulder stabilization program that includes rotator cuff and periscapular muscle strengthening exercises should be undertaken; if this program fails, operative stabilization may be performed.
      Multidirectional shoulder instability generally is believed to be more common in women, consistent with the female tendency toward general ligamentous laxity. The typical patient with multidirectional shoulder instability is younger than 30 years and presents with acute onset of shoulder pain after an inciting event. In these patients, the pain typically is aggravated by extreme positions of the arm including abduction and external rotation that exacerbates anterior instability as well as flexion and adduction that exacerbates posterior instability. The vast majority of patients with multidirectional shoulder instability respond to nonoperative treatment including rotator cuff strengthening and scapular stabilization.
      • Sherbondy PS
      • McFarland EG
      Shoulder instability in the athlete.
      Thoracic outlet syndrome, a cause of shoulder pain seen more commonly in women, is due to compression of the subclavian artery and vein as well as the brachial plexus within the thoracic outlet. Occasionally, a cervical rib is noted to compress these structures; however, the syndrome may exist in the absence of a cervical rib. Patients typically experience pain in the shoulder and hand as well as occasional paresthesias and, rarely, weakness of the affected upper extremity. With associated vascular compromise, patients may experience coolness in the upper extremity, particularly after exercise. Risk factors for thoracic outlet syndrome include a long thin neck, large breasts, and poor posture. Nonoperative treatment frequently is successful and includes rest, anti-inflammatory medication, and rehabilitation to correct poor posture. Rarely, patients require surgery consisting of decompression with resection of the first rib.
      • Huang JH
      • Zager EL
      Thoracic outlet syndrome.
      • Degeorges R
      • Reynaud C
      • Becquemin JP
      Thoracic outlet syndrome surgery: long-term functional results.

      ADHESIVE CAPSULITIS

      Adhesive capsulitis consists of restricted active and passive range of motion of the glenohumeral joint. This condition is due to inflammation of the glenohumeral capsule and synovium that results in the development of adhesions and manifests as decreased range of motion of the shoulder. The typical patient is a woman between age 40 and 60 years. Of those affected with adhesive capsulitis, 70% are women. Other risk factors include a history of diabetes mellitus, trauma, prolonged immobilization, thyroid disease, stroke, or myocardial infarction.
      Patients present typically with progressive, painful loss of motion of the shoulder. Radiographs should be obtained to rule out glenohumeral arthritis, calcific tendinitis, or rotator cuff disease.
      • Castellarin G
      • Ricci M
      • Vedovi E
      • et al.
      Manipulation and arthroscopy under general anesthesia and early rehabilitative treatment for frozen shoulders.
      • Neviaser RJ
      • Neviaser TJ
      The frozen shoulder: diagnosis and management.
      Treatment is aimed at decreasing pain and inflammation and increasing range of motion. Activity modification and anti-inflammatory medications may be supplemented with an intra-articular glenohumeral corticosteroid injection. A formal rehabilitation program that includes postural training, therapeutic modalities to decrease pain and inflammation, and gentle, pain-free joint mobilization is indicated.
      • Neviaser RJ
      • Neviaser TJ
      The frozen shoulder: diagnosis and management.
      • Pajareya K
      • Chadchavalpanichaya N
      • Painmanakit S
      • Kaidwan C
      • Puttaruksa P
      • Wongsaranuchit Y
      Effectiveness of physical therapy for patients with adhesive capsulitis: a randomized controlled trial.
      • Buchbinder R
      • Hoving JL
      • Green S
      • Hall S
      • Forbes A
      • Nash P
      Short course prednisolone for adhesive capsulitis (frozen shoulder or stiff painful shoulder): a randomised, double blind, placebo controlled trial.
      Patients who do not respond to conservative treatment may require closed manipulation of the joint under anesthesia and/or arthroscopic release of adhesions.
      • Castellarin G
      • Ricci M
      • Vedovi E
      • et al.
      Manipulation and arthroscopy under general anesthesia and early rehabilitative treatment for frozen shoulders.
      • Neviaser RJ
      • Neviaser TJ
      The frozen shoulder: diagnosis and management.

      DISORDERS OF THE FOOT

      Among the most common foot and ankle disorders in women are hallux valgus deformities, bunionettes, hammertoes, and neuromas. In a study by Frey et al
      • Frey C
      • Thompson F
      • Smith J
      Update on women's footwear.
      in 1995, 80% of 356 women reported pain while wearing shoes, and 76% had 1 or more forefoot deformities. Anatomically, a woman's foot differs from a man's in having on average a narrower hindfoot, a relatively increased forefoot-to-hind-foot width, and increased pronation. Also, because of societal pressures and fashion trends, some women wear shoes that are narrower than the women's feet and have narrow toe boxes. High heels shift the forefoot forward into the toe box, causing crowding of the toes and tightness of the heel cords.
      • Frey C
      Foot health and shoewear for women.
      • Coughlin MJ
      • Thompson FM
      The high price of high-fashion footwear.
      The hallux valgus deformity is a lateral deviation of the great toe. It is seen in conjunction with a bunion deformity, which is a medial prominence in the region of the first metatarsal head. Hallux valgus deformity occurs 9 times more frequently in women than in men and is encountered almost exclusively in cultures in which shoes are worn. A bunionette is a lateral prominence in the region of the fifth metatarsal head and is frequently associated with varus deviation of the fifth toe. A hammertoe has a hyperextended metatarsophalangeal joint with a hyperflexed proximal interphalangeal joint and a hyperextended distal interphalangeal joint. Trauma, neuromuscular disease, and systemic disorders such as rheumatoid arthritis can cause hammertoes; however, the most common cause, similar to that of hallux valgus deformities and bunionettes, is pressure from shoewear.
      • Frey C
      Foot health and shoewear for women.
      • Coughlin MJ
      • Thompson FM
      The high price of high-fashion footwear.
      Interdigital neuromas, caused by compression of the interdigital nerve between the metatarsal heads, are significantly more common in women, presumably due to footwear differences between men and women.
      • Wu KK
      Morton's interdigital neuroma: a clinical review of its etiology, treatment, and results.
      Neuromas are most frequently located in the third interspace, with symptoms of plantar foot pain aggravated by constrictive footwear.
      • Frey C
      Foot health and shoewear for women.
      • Coughlin MJ
      • Thompson FM
      The high price of high-fashion footwear.
      The most common cause of forefoot problems in women is ill-fitting shoes; thus, the first-line treatment for all the previously mentioned disorders is footwear modification. Wide toe box shoes without seams are necessary when painful bony prominences are present. Patients with hammertoes may need extra-deep shoes to accommodate the prominent proximal interphalangeal joints. Convincing patients to change from traditional, fashionable shoes to accommodative footwear can be difficult. Educating patients from a young age about proper footwear is essential. For some patients, pain is not adequately controlled with footwear modification, and thus surgery may be indicated. Surgery involves correction of deformities and excision in the case of painful neuromas. Generally, surgery is not indicated for cosmesis alone because the risks of infection, postoperative pain, nonunion, and deformity recurrence outweigh the potential benefits.
      • Frey C
      Foot health and shoewear for women.
      • Coughlin MJ
      • Thompson FM
      The high price of high-fashion footwear.

      STRESS FRACTURES

      Studies have indicated that stress fractures are more common in women than in men, particularly in military recruits.
      • Lappe JM
      • Stegman MR
      • Recker RR
      The impact of lifestyle factors on stress fractures in female Army recruits.
      It is unclear whether this difference represents a lower level of general conditioning before the start of basic training or differences in bone density, hormonal environment, or biomechanics.
      • Lappe JM
      • Stegman MR
      • Recker RR
      The impact of lifestyle factors on stress fractures in female Army recruits.
      There is less evidence that women athletes are more predisposed to stress fractures, although it is agreed that women appear to be more prone to stress fractures of the femur, pelvis, and metatarsal.
      Female athletes who participate in certain sports may be more susceptible to particular stress fractures.
      • Munoz MT
      • de la Piedra C
      • Barrios V
      • Garrido G
      • Argente J
      Changes in bone density and bone markers in rhythmic gymnasts and ballet dancers: implications for puberty and leptin levels.
      Stress fractures are seen most commonly in women who participate in track and field, followed by those involved with crew, basketball, lacrosse, and soccer.
      • Bennell KL
      • Brukner PD
      Epidemiology and site specificity of stress fractures.
      The most common sites are the tibia, fibula, metatarsals, and sesamoid bones of the foot. Stress fractures also are seen in the tarsal navicular, pubic ramus, pars interarticularis, femoral neck and shaft, patella, calcaneus, and talus.
      • Bennell KL
      • Brukner PD
      Epidemiology and site specificity of stress fractures.
      • Hulkko A
      • Orava S
      Stress fractures in athletes.
      Athletes involved with rowing and golf may experience rib stress fractures, and those involved with pitching are at risk of humeral and olecranon stress fractures.
      • Bennell KL
      • Brukner PD
      Epidemiology and site specificity of stress fractures.
      Prevention of stress fractures may involve avoidance of overtraining, use of proper sport-specific footwear such as a running-type shoe with adequate shock-absorption capabilities for long-distance running, and attention to proper technique. An athlete beginning an exercise program should consider consulting with a physical therapist or trainer to address potential technical or training errors.
      When a stress fracture is suspected but plain radiographic findings are normal, a bone scan or magnetic resonance image may be helpful in making a diagnosis. Most stress fractures respond well to activity modification, protected weight bearing, and in some cases, immobilization. Activities that cause pain should be avoided. Fractures that exhibit delayed union may require an external bone stimulator. Fractures of the fifth metatarsal, femoral neck, and tarsal navicular are at increased risk of displacement and nonunion and therefore should be treated more aggressively with non-weight-bearing and possible surgical intervention. Fractures of the superior aspect of the femoral neck are particularly at risk of displacement and should be treated aggressively. Nonhealing fractures of the anterior tibia also may require surgery.
      • Brukner P
      • Bennell K
      Stress fractures in female athletes: diagnosis, management and rehabilitation.
      • Monteleone Jr, GP
      Stress fractures in the athlete.

      CONCLUSION

      Differences between men and women in anatomy, physiology, hormonal environment, and societal pressures lead to an increased incidence of certain injuries and musculoskeletal disorders in women. An understanding of the common musculoskeletal injuries and disorders in women as well as the unique issues surrounding women's musculoskeletal health may aid not only in treatment but also in prevention.

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