Secondary Logo

Share this article on:

Male and Female Differences in Musculoskeletal Disease

Wolf, Jennifer Moriatis MD; Cannada, Lisa MD; Van Heest, Ann E. MD; O’Connor, Mary I. MD; Ladd, Amy L. MD

JAAOS - Journal of the American Academy of Orthopaedic Surgeons: June 2015 - Volume 23 - Issue 6 - p 339–347
doi: 10.5435/JAAOS-D-14-00020
Review Article

Gender differences exist in the presentation of musculoskeletal disease, and recognition of the differences between men and women’s burden of disease and response to treatment is key in optimizing care of orthopaedic patients. The role of structural anatomy differences, hormones, and genetics are factors to consider in the analysis of differential injury and arthritic patterns between genders.

Musculoskeletal disorders are characterized by a lack of ease of function and movement,1 and in men and women, the presentation of these disorders differs. Furthermore, there are differences in how men and women communicate with physicians, as well as differences in how male and female healthcare providers relate to patients. On average, female physicians spend 2 minutes longer with patients;2 however, patient perceptions of female physicians are consistently more likely to be negative compared with male physicians.3 Recent and ongoing investigations characterize the effect of gender specific to ligaments, bone quality, and susceptibility to osteoarthritis (OA). Identifying both similarities and differences will yield better analyses of disease, provide opportunities for improved treatment methods and outcomes, and ultimately deliver better musculoskeletal care to every orthopaedic patient.

Back to Top | Article Outline

Ligament and Tendon Injuries and Disease

The balance between stability and mobility of joints is critically dependent on the soft tissues that stabilize the joints. The observed gender differences in joint injury, best known at the knee, may derive in part from structural tissue differences at either the cellular or the molecular level.

Back to Top | Article Outline

Anterior Cruciate Ligament Injuries

The incidence of anterior cruciate ligament (ACL) injury in young athletes is highest in cutting sports, such as soccer, basketball, and football.4 Arendt et al5 and others have shown a significantly higher incidence of ACL tears in women compared with age- and sport-matched men, with a ratio of approximately 3:1. The reason for this difference in injury occurrence is not completely understood, although a combination of factors is likely contributory. Flaxman et al6 noted neuromuscular differences and significantly greater activation of knee joint stabilizing muscles, including the tensor fascia lata and the rectus femoris, in women compared with men. Other authors report gender differences in knee abduction angle and flexion velocity in jump landing and propose that these findings contribute to the differences in the tear rate of the ACL.

Anatomic factors have also been proposed to explain the gender difference in ACL injury. In 1993, Souryal and Freeman7 reported that the width of the intercondylar notch was inversely related to the incidence of ACL tear; thus, a stenotic or narrowed notch, seen more frequently in women, was a risk factor for injury (Figure 1). Additionally, an increased quadriceps angle and tibial slope have been proposed as risk factors in women (Figure 2).

Figure 1

Figure 1

Figure 2

Figure 2

The influence of reproductive hormones has also been hypothesized to play a role. The presence of estrogen, androgen, and relaxin receptors has been confirmed in ACL fibroblasts,8,9 but receptor binding and the potential impact on the ligament itself are not specifically known. In a study of 26 healthy women, Park et al10 noted increased knee joint laxity during the ovulation phase of the menstrual cycle and reduced stiffness in the knee. These findings suggest that a shift in the levels of estrogen and progesterone may have an impact on the ACL. Relaxin, a hormone that increases ligament laxity in women during pregnancy, is also normally circulating in nonpregnant women and in men. Dragoo et al11 prospectively evaluated relaxin levels in female athletes and the incidence of ACL tear over a period of 4 years; the authors noted higher serum relaxin levels in athletes who sustained an ACL injury compared with athletes who did not sustain an injury.

After ACL reconstruction, women are less likely to return to sport than men.12 In addition, prospective studies show that women have a higher rate of contralateral ACL injury after sustaining an ACL tear.13

Back to Top | Article Outline

Ankle Instability

Ankle sprain is an extremely common injury, occurring in both athletes and the general population, and many persons go on to develop chronic ankle instability. This instability is thought to be multifactorial, with insufficiency of the stabilizing ligaments, altered proprioception, and neuromuscular deficit all playing a role.14 In stance and gait studies, men and women have different stabilizing strategies, suggesting that these differences may affect joint stability during injury.15 Ligamentous laxity of the ankle joint has been shown to be greater in women; talar tilt stress radiography results revealed that talar tilt in 58 athletes averaged 1.07° in men and 3.20° in women.16 In an epidemiologic meta-analysis, Doherty et al17 noted that women sustain ankle sprains nearly twice as often as men: 13.6 sprains compared with 6.94 sprains, respectively, per 1,000 exposures. Other studies show that girls and women have higher rates of chronic ankle instability in both high school and collegiate settings.18

Back to Top | Article Outline

Shoulder Instability

Multidirectional shoulder instability (MDI) is thought to occur more commonly in women. Interestingly, a review of the literature about MDI noted that women make up less than half the population reported in clinical series.19 However, Beasley et al20 reported on MDI in the female athlete and attributed the condition to the greater overall joint laxity seen in women.

In traumatic shoulder dislocation, most data indicate minimal differences between males and females.21 However, Borsa et al22 tested anterior shoulder joint laxity using glenohumeral instrumentation in healthy men and women; the authors noted that women had greater anterior glenohumeral laxity than men (women, 11.4 ± 2.8 mm, and men, 8.3 ± 2.2 mm; P < 0.001) and decreased stiffness (women, 16.3 ± 4.2 N × mm[−1], and men, 20.5 ± 5.0 N × mm[−1]; P < 0.01). Kaipel et al23 evaluated outcomes after arthroscopic Bankart stabilization and noted inferior outcomes in women, including lower Constant-Murley scores.

Back to Top | Article Outline

de Quervain Tenosynovitis

In de Quervain disease, tenosynovitis is thought to occur more frequently in women. Wolf et al24 reported on a database examining 11,000 cases of de Quervain tenosynovitis. Women had a significantly higher rate of de Quervain tenosynovitis, with 2.8 cases per 1,000 person years compared with men at 0.6 cases per 1,000 person years. de Quervain tenosynovitis has also been reported to be more common in pregnant women and those who are postpartum.25

Back to Top | Article Outline

Osteoporosis and Fragility Fractures

Defining the Problem

Osteoporosis is characterized by low bone mass and micro architectural deterioration of bone tissue, leading to bone fragility and an increased risk of hip fractures.26 The World Health Organization has defined osteoporosis in terms of bone mass that is >2.5 standard deviations below the mean of peak bone mass in healthy young adults.27 Based on bone mineral density measurements at the hip or spine, the prevalence of osteoporosis in the United States in persons aged ≥50 years is reported to be 4% in men and 16% in women.28

Back to Top | Article Outline

Osteoporotic Hip Fractures

The etiology of osteoporosis between men and women differs. Estrogen metabolism is thought to be important in bone health, and once a woman enters menopause, there is an estrogen deficiency.29 Postmenopausal osteoporosis is the most common cause of osteoporosis in women and is linked to the occurrence of hip fractures. In contrast, when older men sustain a hip fracture, osteoporosis is only one of several likely diagnoses; the etiology of hip fracture is often the result of underlying disease, including rheumatoid arthritis, alcoholism, or gonadal deficiencies.30 Other risk factors that contribute to osteoporosis in men include tobacco use, low physical activity, corticosteroid use, hypothyroidism, hyperparathyroidism, and hypercalciuria.31 Overall, the risk of hip fracture is three times lower in men compared with women based on age and other risk factors; therefore, men who sustain hip fractures are thought to have a greater magnitude of bone loss. Men fare worse than women after hip fractures, with increased morbidity and a twofold increase in mortality. In addition, undertreatment and under-recognition of osteoporosis has been documented in men.30,32 Evaluation of the literature shows a relative lack of information regarding knowledge about osteoporosis in men.

Back to Top | Article Outline

Bone Mass Differences by Gender

During growth, periosteal expansion is greater in males, thus establishing a gender difference in bone at an early age. In young adulthood, men have a bone area that is 35% to 42% larger than women, consistent with their larger body size.33 At full maturity, men’s bones are, in general, wider and longer than women's bones. Over time, trabecular bone loss is similar in both men and women, but the cortical resorption is greater in women (25%) than in men (18%).33 Interestingly, in men with hip fractures, the width of the femoral neck is smaller.34

Back to Top | Article Outline

Upper Extremity Fractures

Fracture patterns in the hand and forearm also show different epidemiologic and frequency patterns for men and women. Chung and Spilson35 reported on 1.5 million cases of hand and forearm fractures in 1998. This large database analysis showed that women made up a significantly higher proportion of the population who sustained radius and ulna fractures (52%) and carpal fractures (67%), whereas men made up a significantly higher proportion of those presenting with metacarpal fractures (76%) and phalangeal fractures (58%).

The prevalence of distal radius fractures is also greater in females, particularly wrist fractures occurring from low-energy trauma, termed fragility fractures. Females have a 6:1 preponderance of age-related increases in wrist fractures compared with males. Decreased bone density, as well as decreased resistance to compressive and bending load with aging, occurs more rapidly in women than in men and accounts for the increased preponderance of distal radius fractures as fragility fractures for women.33

Back to Top | Article Outline

Treatment Differences After Osteoporotic Fractures

The gender gap in diagnosis and treatment of osteoporosis after a fragility fracture is wide. In Canada, 10.3% of men who sustained a fragility fracture reported a diagnosis of osteoporosis at 5-year follow-up,36 indicating that approximately 90% of men were untreated. In the primarily male veteran population under care in the Veterans Health Administration system, a study of patients with hip fractures showed that only 1.2% of patients who sustained a hip fracture underwent bone mineral density testing and that 14.5% received osteoporosis therapy within 12 months of sustaining a fracture.37

In a claims-based study of Medicare data, the results demonstrated that postfracture osteoporosis care was uncommon, particularly in men and in African Americans.38 This gap in care is demonstrated in multiple studies. Making the connection of a possible diagnosis of osteoporosis in an elderly male who sustained a hip fracture is important, and it allows for identification of the etiology and subsequent treatment to prevent further fractures. The treatment of osteoporosis is important for longevity and for preventing future fractures.

Back to Top | Article Outline

Gender Differences in Recovery

It is well known that hip fractures represent an injury with risk of morbidity and mortality. The range of complications after hip fracture include admission to an intensive care unit, deep vein thrombosis, wound dehiscence, bedsores, pneumonia, failure of fixation, and death.39 Pugely et al40 developed a 30-day risk calculator for morbidity and mortality following hip fracture surgery. Factors associated with an increased morbidity and mortality included age >80 years and male gender. This model supported previous studies regarding significantly increased mortality after hip fractures in men. In all age groups, there is excess mortality after hip fractures in men compared with women. One study indicated that males with hip fractures were younger and had greater comorbidity at the time of fracture.41

The number of osteoporotic fractures of the hip is increasing as the population ages; thus, they are considered to be a major health problem with a significant cost burden to society. When a patient sustains an osteoporotic fracture, prompt evaluation and treatment with a team approach is important. The elderly have less tolerance for repeat procedures; therefore, minimizing complications and morbidities is paramount. The orthopaedic surgeon should be proactive in recognizing the underlying etiology and have a system in place for treatment plans and/or referrals because evaluation and treatment of osteoporosis, regardless of gender, can help save lives.

Back to Top | Article Outline

Gender Differences in Arthritis

Osteoarthritis of the Knee

OA of the knee develops more frequently in women compared with men.42 MRI studies confirm this epidemiologic finding. In asymptomatic women between ages 50 and 79 years, MRI studies showed that women lose cartilage in the tibia at four times the annual rate of men.43 Furthermore, patellofemoral arthritis is more common and severe in women compared with men. After adjusting for age, body mass index, and patella bone volume at baseline, Brennan et al44 showed that women lose patellar cartilage at an annual rate of 3.3% compared with 1.4% for men (P = 0.03) based on MRI studies in patients with symptomatic OA of the knee over a period of 4.5 years.

Why women have this higher disease burden for OA of the knee is unclear. Because human articular cartilage contains estrogen receptors45 and the incidence of OA of the knee is higher in postmenopausal women, the role of estrogen in OA of the knee has been studied. Hormone replacement therapy has been noted to decrease joint pain46 but was not shown to be protective against the development of radiographic OA of the knee at 14 years in the Framingham study.47 Furthermore, in the Women’s Health Initiative cohort of more than 26,000 women, estrogen replacement appeared to prevent some knee arthroplasties (ie, approximately 13% decrease), but this finding was not significant when analyzed by intent to treat; no decrease was seen in women given estrogen plus progestin.48 Certainly, other biologic processes (eg, inflammation) and physical factors (eg, obesity, physical activity) can influence the development and progression of OA of the knee. Obesity is a predictor of onset and progression of OA of the knee; this association is stronger in women than in men and may modulate OA via an increase in inflammatory cytokines and mechanical factors within the joint.49 Understanding gender-based biologic differences that relate to the higher burden of disease in women remains an area of active investigation.

With the introduction of a gender-specific knee implant, considerable interest was generated relative to the differences between genders in total knee arthroplasty (TKA) outcomes. Merchant et al50 concluded that women “achieve essentially equal results compared with men” based on a review of primary TKA studies in which the focus was primarily implant survival/failure, with a few studies showing no significant difference in outcomes scores. Likewise, Ritter et al51 concluded that “improvement after TKA is similar for men and women, with few clinically significant differences.” However, data show that differences are seen between men and women both before and after surgery depending on the parameter selected.

Some studies have demonstrated that women had statistically significantly greater pain before surgery (Table 1).51-53 Two studies reported a statistically significant difference in postoperative pain at 5 years after TKA, but the clinical differences were small.51,52 However, Singh and Lewallen54 reported that moderate to severe levels of pain were higher in women than in men after primary TKA at 2 and 5 years (9% versus 6.6% and 7.9% versus 6.5%, respectively). Women were more likely to use opioid pain medication at 2 years and 5 years after primary TKA compared with men.55,56 These data support the conclusion that women report more pain before TKA and are more likely to have continued pain after surgery.

Table 1

Table 1

Does a gender-specific TKA implant improve outcomes? Although differences between the bony anatomy of the knee joint of men and women are well documented, a technology review by the American Academy of Orthopaedic Surgery57 in 2008 did not “consistently show differences between men and women in most of the outcomes of tricompartmental total knee replacement surgery,” calling into question the need for a gender-specific implant. Moreover, a systemic review of the MEDLINE database by Johnson et al58 in 2011 concluded that function and satisfaction scores did not differ with use of gender-specific implants compared with unisex implants.

Women also do not have the same functional outcome as men following TKA; female gender was noted to be a predictor of moderate to severe functional limitation at 2 and 5 years in a large registry study.56 Even with adjustment for preoperative functional limitation, demographics, and comorbidities, women were noted to have poorer function and higher dependence on gait aids compared with men.56 At a minimum of 5 years following surgery, several studies noted significant differences in function using The Knee Society and the Western Ontario and McMaster Universities Osteoarthritis Index scores.51,52

Worse preoperative function in women may be related to gender-based differences in neuromuscular activation. Arthrogenic muscle inhibition is a process in which a change in the discharge of sensory receptors in the knee joint influences other neural pathways (including the central nervous system), resulting in neural inhibition that prevents the quadriceps from being fully activated.59 Such arthrogenic muscle inhibition has been found to be more severe in women with OA.60 Petterson et al60 studied quantitative physical functional tests in TKA candidates and found that women had reduced function compared with men in both the surgical and normal control group, but this difference was magnified in women. Researchers have suggested that women undergo TKA when the disease is in a more advanced state.

In women undergoing TKA, societal and gender issues may contribute to women having worse preoperative function and pain compared with men. In contrast to studies that show that women access preventive care more frequently than men,61 women may be less willing to undergo surgery than men, or they present at an older age. Based on a survey of 1,722 patients undergoing primary total hip arthroplasty or TKA in Canada, Gandhi et al62 reported that women living alone more commonly delayed surgery and had poorer 1-year outcomes. Surgeon recommendation for TKA may also be a factor in women undergoing surgery at a more advanced disease state. In a study of standardized male and female patients with moderate knee OA, the odds of an orthopaedic surgeon recommending surgery to the male patient were 22 times that of the female patient.63 The authors concluded that unconscious bias on the part of the physician contributed to disparities between men and women in rates of use of TKA. A study of surgical consultation rates among patients with hip or knee OA is supportive of this concept; results showed that men visited surgeons at a higher rate than women.64 More research into the role of unconscious bias relative to gender, race, and ethnicity is needed to better understand the potential impact of such bias on health outcomes.

In summary, differences between men and women exist relative to knee OA. Women have a higher burden of disease, greater pain, and functional impairment at the time of TKA, and they do not appear to recover to the same level as men following TKA. Unconscious bias on the part of physicians may contribute to this disparity. Further research is needed to better understand these differences and develop effective strategies to improve outcomes for all patients.

Back to Top | Article Outline

Basilar Thumb Arthritis

Gender differences exist for thumb carpometacarpal (CMC) arthritis, the most common site for OA in the upper extremity. In persons older than 75 years, the prevalence of radiographic CMC degeneration is 25% in men and 40% in women.65 The etiology of CMC joint arthritis is multifaceted; causes may include ligament hypermobility, hormonal influences, and anatomic structural differences. In a study of 50 patients by Jónsson et al,66 the authors reported that thumb CMC arthritis correlated with joint hypermobility (ie, measured by passive extension of the fifth finger >90°). In the authors’ study, women exhibited a higher amount of joint laxity and a higher incidence of CMC joint arthritis. Wolf et al67 examined 163 subjects and reported that in normal volunteers, generalized joint laxity, as measured by the Beighton score, was positively correlated with increased mobility of the CMC joint.

Reproductive hormone differences, such as prolactin, relaxin, and estrogen, have been postulated as etiologies for increased laxity and subsequent arthritis of the thumb CMC joint. In a 2014 study by Wolf et al,68 49 patients undergoing CMC arthroplasty underwent laxity examination, testing of blood levels for relaxin, and analysis for relaxin receptors on the anterior oblique ligament. Although women demonstrated more joint laxity than men, conclusive data regarding the role of laxity in sex hormones in thumb CMC arthritis were lacking, and further investigation into the role of relaxin hormone was suggested. The sex differences of other reproductive hormones have also been investigated as to whether they may account for the disparities in increased prevalence of OA in women; to date, there are no conclusive results.

The unique anatomy of the thumb CMC joint may also make it particularly susceptible to osteoarthritic change. Although the thumb interphalangeal and metacarpophalangeal joints are primarily hinged joints in a flexion and extension plane, the thumb CMC joint provides a breadth of motion in multiple planes to perform tasks that are uniquely human, including grasp and pinch (Figure 3). The joint morphology of the metacarpal on the trapezium is a saddle joint with two opposing saddles perpendicular to each other. The CMC joint works biomechanically as a universal joint. The anatomy of the joint allows the motions of flexion, extension, adduction, and abduction. These motions can be combined to form the complex movements of opposition, retropulsion, palmar abduction, radial abduction, palmar adduction, and radial adduction.69

Figure 3

Figure 3

The wear patterns for articular cartilage loss in the progression of thumb CMC arthritis show that with increasing stages of OA, cartilage degeneration is initiated on the radial quadrant of the metacarpal and progresses to the volar quadrant. On the trapezium, wear is seen on the dorsal radial quadrant and progresses to the volar quadrant in late-stage OA, as well.70 In a study of 46 osteoarthritic thumb CMC joints, Xu et al71 reported that the joint topography in women is less congruent, has smaller contact areas, and is more likely to experience higher contact stresses than the joint topography in men.

Back to Top | Article Outline

Summary

Gender differences exist in many areas of musculoskeletal disease. The role of hormones, differential anatomy, joint stability, and bone quality must be considered when caring for orthopaedic patients, and the differences in recovery after injury and surgery are also important to consider. Gender must be considered as a factor in the diagnosis and treatment of many common diseases.

Back to Top | Article Outline

References

References printed in bold type are those published within the past 5 years.

1. Merriam Webster's Dictionary. Online volume 2014.
2. , : Physician gender and patient-centered communication: A critical review of empirical research. Annu Rev Public Health 2004;25:497–519
3. , , , , : Satisfaction, gender, and communication in medical visits. Med Care 1994;32(12):1216–1231
4. , , , , , : A multisport epidemiologic comparison of anterior cruciate ligament injuries in high school athletics. J Athl Train 2013;48(6):810–817
5. , , : Anterior cruciate ligament injury patterns among collegiate men and women. J Athl Train 1999;34(2):86–92
6. , , : Sex-related differences in neuromuscular control: Implications for injury mechanisms or healthy stabilization strategies? J Orthop Res 2014;32(2):310–317
7. , : Intercondylar notch size and anterior cruciate ligament injuries in athletes: A prospective study. Am J Sports Med 1993;21(4):535–539
8. , , , , : Quantitation of estrogen receptors and relaxin binding in human anterior cruciate ligament fibroblasts. In Vitro Cell Dev Biol Anim 2006;42(7):176–181
9. , : Effect of testosterone on the female anterior cruciate ligament. Am J Physiol Regul Integr Comp Physiol 2005;289(1):R15–R22
    10. , , , , : Changing hormone levels during the menstrual cycle affect knee laxity and stiffness in healthy female subjects. Am J Sports Med 2009;37(3):588–598
    11. , , , , , : Prospective correlation between serum relaxin concentration and anterior cruciate ligament tears among elite collegiate female athletes. Am J Sports Med 2011;39(10):2175–2180
    12. , , , : Return to play and future ACL injury risk after ACL reconstruction in soccer athletes from the Multicenter Orthopaedic Outcomes Network (MOON) group. Am J Sports Med 2012;40(11):2517–2522
    13. , , , , : Incidence of contralateral and ipsilateral anterior cruciate ligament (ACL) injury after primary ACL reconstruction and return to sport. Clin J Sport Med 2012;22(2):116–121
    14. : Commentary: Functional ankle instability revisited. J Athl Train 2002;37(4):512–515
    15. , , , : Gender differences in lower extremity gait biomechanics during walking using an unstable shoe. Clin Biomech 2010;25(10):1047–1052
    16. , : Differences in men’s and women’s mean ankle ligamentous laxity. Iowa Orthop J 2000;20:46–48
    17. , , , , , : The incidence and prevalence of ankle sprain injury: A systematic review and meta-analysis of prospective epidemiological studies. Sports Med 2014;44(1):123–140
    18. , , , , : Prevalence of chronic ankle instability in high school and division I athletes. Foot Ankle Spec 2014;7(1):37–44
    19. , , : Arthroscopic treatment of multidirectional glenohumeral instability: 2- to 5-year follow-up. Arthroscopy 2001;17(3):236–243
    20. , , : Multidirectional instability of the shoulder in the female athlete. Clin Sports Med 2000;19(2):331–349
    21. , , , , , : The incidence and characteristics of shoulder instability at the United States Military Academy. Am J Sports Med 2007;35(7):1168–1173
    22. , , : Patterns of glenohumeral joint laxity and stiffness in healthy men and women. Med Sci Sports Exerc 2000;32(10):1685–1690
    23. , , , , : Sex-related outcome differences after arthroscopic shoulder stabilization. Orthopedics 2010;33(3
    24. , , : Incidence of de Quervain’s tenosynovitis in a young, active population. J Hand Surg Am 2009;34(1):112–115
    25. : Occurrence of de Quervain’s disease in postpartum women. J Fam Pract 1991;32(3):325–327
    26. : Knowledge about osteoporosis: Assessment, correlates and outcomes. Osteoporos Int 2005;16(2):115–127
    27. NIH Consensus Development Panel on Osteoporosis Prevention, Diagnosis, and Therapy: Osteoporosis prevention, diagnosis, and therapy. JAMA 2001;285(6):785–795
    28. , , , , : Estimating prevalence of osteoporosis: Examples from industrialized countries. Arch Osteoporos 2014;9(1):182
    29. : Gender differences in osteoporosis and fractures. Clin Orthop Relat Res 2011;469(7):1900–1905
    30. , , , : Sex and gender considerations in male patients with osteoporosis. Clin Orthop Relat Res 2011;469(7):1906–1912
    31. , , , : Osteoporosis in men: Epidemiology, diagnosis, prevention, and treatment. Clin Ther 2004;26(1):15–28
    32. , , , ; Osteoporotic Fractures in Men (MrOS) Research Group: Loss of hip BMD in older men: The osteoporotic fractures in men (MrOS) study. J Bone Miner Res 2009;24(10):1728–1735
      33. , , , : Population-based analysis of the relationship of whole bone strength indices and fall-related loads to age- and sex-specific patterns of hip and wrist fractures. J Bone Miner Res 2006;21(2):315–323
      34. : The growth and age-related origins of bone fragility in men. Calcif Tissue Int 2004;75(2):100–109
      35. , : The frequency and epidemiology of hand and forearm fractures in the United States. J Hand Surg Am 2001;26(5):908–915
      36. , , , ; CaMos Research Group: The osteoporosis care gap in men with fragility fractures: The Canadian Multicentre Osteoporosis Study. Osteoporos Int 2008;19(4):581–587
      37. , , , : Testing and treatment for osteoporosis following hip fracture in an integrated U.S. healthcare delivery system. Osteoporos Int 2011;22(12):2973–2980
      38. , , , : Quality of osteoporosis care of older Medicare recipients with fragility fractures: 2006 to 2010. J Am Geriatr Soc 2013;61(11):1855–1862
      39. , , , , , : Use of medical comorbidities to predict complications after hip fracture surgery in the elderly. J Bone Joint Surg Am 2010;92(4):807–813
      40. , , , , , : A risk calculator for short term morbidity and mortality following hip fracture surgery. J Orthop Trauma 2014;28(2):63–69
      41. , , , et al: Cigarette smoking, birthweight and osteoporosis in adulthood: Results from the Hertfordshire cohort study. Open Rheumatol J 2008;2:33–37
      42. , , , , , : The prevalence of knee osteoarthritis in the elderly: The Framingham Osteoarthritis Study. Arthritis Rheum 1987;30(8):914–918
      43. , , , : Women have increased rates of cartilage loss and progression of cartilage defects at the knee than men: A gender study of adults without clinical knee osteoarthritis. Menopause 2009;16(4):666–670
      44. , , , : Women lose patella cartilage at a faster rate than men: A 4.5-year cohort study of subjects with knee OA. Maturitas 2010;67(3):270–274
      45. , , , , : Expression of genes for estrogen receptors alpha and beta in human articular chondrocytes. Osteoarthritis Cartilage 1999;7(6):560–566
      46. , , , ; Women’s Health Initiative Investigators: Menopausal symptoms and treatment-related effects of estrogen and progestin in the Women’s Health Initiative. Obstet Gynecol 2005;105(5 Pt 1):1063–1073
      47. , , , : Estrogen replacement therapy and worsening of radiographic knee osteoarthritis: The Framingham Study. Arthritis Rheum 1998;41(10):1867–1873
      48. , , , : Effect of hormone therapy on risk of hip and knee joint replacement in the Women’s Health Initiative. Arthritis Rheum 2006;54(10):3194–3204
      49. , , , : Mechanical contributors to sex differences in idiopathic knee osteoarthritis. Biol Sex Differ 2012;3(1):28
      50. , , , : The female knee: Anatomic variations and the female-specific total knee design. Clin Orthop Relat Res 2008;466(12):3059–3065
      51. , , , , : The clinical effect of gender on outcome of total knee arthroplasty. J Arthroplasty 2008;23(3):331–336
      52. , , , : Analysis of the outcome in male and female patients using a unisex total knee replacement system. J Bone Joint Surg Br 2009;91(3):357–360
        53. , , , , , : The John Insall Award: Gender-specific total knee replacement: Prospectively collected clinical outcomes. Clin Orthop Relat Res 2008;466(11):2612–2616
          54. , : Predictors of use of pain medications for persistent knee pain after primary total knee arthroplasty: A cohort study using an institutional joint registry. Arthritis Res Ther 2012;14(6):R248
          55. , , : The impact of gender, age, and preoperative pain severity on pain after TKA. Clin Orthop Relat Res 2008;466(11):2717–2723
          56. , , , : Predictors of moderate-severe functional limitation after primary total knee arthroplasty (TKA): 4701 TKAs at 2-years and 2935 TKAs at 5-years. Osteoarthritis Cartilage 2010;18(4):515–521
          57. Gender-specific knee replacements: A technology overview. J Am Acad Orthop Surg 2008;16(2):63–67
          58. , , : Do we need gender-specific total joint arthroplasty? Clin Orthop Relat Res 2011;469(7):1852–1858
          59. , : Quadriceps arthrogenic muscle inhibition: Neural mechanisms and treatment perspectives. Semin Arthritis Rheum 2010;40(3):250–266
          60. , , , : Disease-specific gender differences among total knee arthroplasty candidates. J Bone Joint Surg Am 2007;89(11):2327–2333
          61. , , : Gender differences in utilization of preventive care services in the United States. J Womens Health (Larchmt) 2012;21(2):140–145
          62. , , , , Effect of sex and living arrangement on the timing and outcome of joint replacement surgery. Can J Surg 2010;53(1):37–41
          63. , , , , , : The effect of patients’ sex on physicians’ recommendations for total knee arthroplasty. CMAJ 2008;178(6):681–687
          64. , , , : Effect of sociodemographic factors on surgical consultations and hip or knee replacements among patients with osteoarthritis in British Columbia, Canada. J Rheumatol 2011;38(3):503–509
          65. , , : The prevalence of degenerative arthritis of the base of the thumb in post-menopausal women. J Hand Surg Br 1994;19(3):340–341
          66. , , , : Hypermobility associated with osteoarthritis of the thumb base: A clinical and radiological subset of hand osteoarthritis. Ann Rheum Dis 1996;55(8):540–543
          67. , , , , : Radiographic laxity of the trapeziometacarpal joint is correlated with generalized joint hypermobility. J Hand Surg Am 2011;36(7):1165–1169
          68. , , , : Relationship of relaxin hormone and thumb carpometacarpal joint arthritis. Clin Orthop Relat Res 2014;472(4):1130–1137
          69. , : Thumb carpal metacarpal arthritis. J Am Acad Orthop Surg 2008;16(3):140–151
          70. , , , , , : Sequential wear patterns of the articular cartilage of the thumb carpometacarpal joint in osteoarthritis. J Hand Surg Am 2003;28(4):597–604
          71. , , , , , : Topography of the osteoarthritic thumb carpometacarpal joint and its variations with regard to gender, age, site, and osteoarthritic stage. J Hand Surg Am 1998;23(3):454–464
          © 2015 by Lippincott Williams & Wilkins, Inc.