Sex & Gender in Acute Care Medicine

Sex & Gender in Acute Care Medicine Chapter 8: Orthopedics and Sports Medicine

Chapter 8: Orthopedics and Sports Medicine NehaRaukar Kimberly Templeton

Introduction • This chapter focuses on the effects of sex and gender on the epidemiology, pathophysiology, diagnosis, and treatment of acute orthopedic and sport-related injuries • Exercise is part of a balanced lifestyle • Women who play sports are healthier, get better grades, are less likely to experience depression and to use alcohol, cigarettes, and drugs than their sedentary counterparts

Introduction • Women who begin playing sports during high school or college are more likely to remain physically active as adults • Women’s participation in athletic activities has increased significantly in the past few decades • There has been a concomitant increase in the incidence of women presenting with a variety of musculoskeletal complaints

Introduction • Sex and gender differences in musculoskeletal injury patterns have attracted research support and clinical endorsement • Since the passage of Title IX of the Educational Amendment of 1972, there has been a more than tenfold increase in women’s participation in high school and collegiate athletics

Introduction • Male and female athletes have different injury patterns because of anatomic, hormonal, neuromuscular, and sport-specific differences • Current research has demonstrated that knee injuries, especially those of the anterior cruciate ligament (ACL) and the patellofemoral joint, have consistent gender specificity

Case • A 17-year-old basketball player presents with a painful, swollen right knee • She is unable to bear weight on the right leg because of pain in her knee, which she cannot flex or extend • She sustained this injury twisting her knee while landing a jump during a game

Clinical Questions • How would you approach this patient? • Is there a physical exam maneuver that will help identify the injury? • What are gender-specific elements in diagnosis and management that you should consider?

Knee – Anterior Cruciate Ligament • The anterior cruciate ligament (ACL) provides sagittal and rotational stability to the knee • According to the orthopedic literature, women are 2 to 8 times more likely to sustain a tear of the ACL than men • More than 38,000 ACL injuries occur in women every year • ACL tears can have significant short- and long-term impact on athletes

Knee – Anterior Cruciate Ligament • ACL tears can interfere with participation in sports and precipitate early onset osteoarthritis • Men are more likely to sustain an ACL injury from contact-related trauma • Women, from non-contact injury • Non-contact injuries typically occur when the athlete attempts to cut/pivot, decelerate rapidly, or land a jump

Knee – Anterior Cruciate Ligament • These activities often result in what has been termed the “point of no return” (Buschbacher et al. 2008): • Loss of control of the hip/pelvis while the hip is internally rotated, the knee is in valgus, the tibia is externally rotated, and the foot is pronated and externally rotated relative to the ankle • This puts abnormal strain on the ACL immediately after initial foot contact

Knee – Anterior Cruciate Ligament • Women’s sports most associated with ACL injury are basketball, soccer, alpine skiing (almost all women who compete for five years will sustain an ACL tear), and lacrosse • But every sport that involves running, turning, or jumping puts women athletes at risk • The relative impacts of anatomy, sex hormone levels, and neuromuscular control on the risk of ACL injury have been the subject of considerable investigation

Knee – Anterior Cruciate Ligament • Lower extremity alignment differs between the sexes in multiple planes • The impact of this difference on risk of ACL injury remains controversial • Women have great hip adduction, knee valgus, and foot pronation than men • These differences increase strain on the ACL

Knee – Anterior Cruciate Ligament • Other differences in lower extremity anatomy between men and women that have been studied with regards to ACL injury include: • Differences in femoral condyle width, tibial slope, lateral compartment alignment, and size of the femoral “notch” • These anatomic factors may increase the inherent instability of women’s knee joints when landing or pivoting

Knee – Anterior Cruciate Ligament • Most studies note significant overlap for both men and women between athletes with some or all of these risk factors and actual likelihood of sustaining an ACL injury • None of these factors has proven to be a significant prognostic indicator of an athlete’s potential for ACL injury

Knee – Anterior Cruciate Ligament • Women’s connective tissue tends to be more lax than men’s due to sex hormone concentrations • Temporal variations in sex hormone levels in individual women also seem to increase risk of ACL injury • Estrogen decreases collagen production • Rising serum estrogen concentrations increase laxity and impair the athlete’s ability to repair microtrauma to the ACL

Knee – Anterior Cruciate Ligament • Relaxin increases soft tissue laxity • Joint laxity appears to be greatest during the luteal phase of the menstrual cycle • A variety of studies have suggested that risk of ACL injuries increases during this phase and varies throughout the menstrual cycle • Unfortunately, most of these studies have been retrospective • More recent prospective studies have not supported this finding

Knee – Anterior Cruciate Ligament • Women athletes should not modify their sports activities during the menstrual cycle • No evidence supports the use of exogenous hormones to regulate the menstrual cycle to decrease risk of ACL injury

Knee – Anterior Cruciate Ligament • Some researchers have suggested that inherent sex differences in neuromuscular control can explain women’s increased risk of ACL injury • Gender-based variability in approaches to conditioning and training may contribute • Recent research strongly correlates lower extremity landing positions with ACL injury risk

Knee – Anterior Cruciate Ligament • When an athlete lands with her hips and knees extended, there is anterior translation of the tibia on the femur and increased valgus stress on the knee • Both hamstring activation and stiffness provide resistance to anterior tibial translation and valgus stress, leading to reduced strain on the ACL

Knee – Anterior Cruciate Ligament • Prior to menarche, girls land their jumps with the same body kinesthetics as boys • Afterward, for reasons still unknown, women tend to land jumps with their hips in internal rotation, their feet flat, and their hips and knees fully extended • This landing position, when combined with static hip adduction and valgus stress of the knee, places considerable strain on the ACL

Knee – Anterior Cruciate Ligament • Women’s post-menarchal landing pattern also reflects sex differences in neuromuscular activation • Women exhibit less hamstring strength than quadriceps strength and have a longer activation time to reach peak hamstring force • Men’s quadriceps and hamstring strength and activation time are equal

Knee – Anterior Cruciate Ligament • Athletes who consistently land in positions that represent the extremes of normal ranges have the greatest risk of ACL injury • Patients who have sustained an ACL tear present with pain and acute hemarthrosis • Their knees swell immediately after the injury • They may or may not be able to bear weight

Knee – Anterior Cruciate Ligament • Pain, swelling, and guarding all interfere with a comprehensive knee examination, especially the Lachman or anterior drawer test • Patients with a history and exam consistent with ACL tear should be immediately referred for further evaluation and management • Evaluation involves obtaining an MRI to confirm the diagnosis and assess for additional joint injury, particularly menisceal tears

Knee – Anterior Cruciate Ligament • The ACL can be reconstructed after injury, stabilizing the knee • This does not protect patients from developing secondary osteoarthritis (OA) as a direct result of articular cartilage injury • Women are at greater risk for developing OA of the knee after ACL injury • Development of OA can be life-altering, therefore, prevention of ACL injury is crucial

Knee – Anterior Cruciate Ligament • Effective prevention programs incorporate strengthening of the muscles and ligaments that support the knee and protect the ACL and PCL • Stretching exercises, balance training, plyometrics • Emphasis on learning and practicing safe landing positions (i.e., landing with both hips and knees flexed, on the balls of the feet)

Other Knee Injuries • The anatomic lower extremity alignment in women that predisposes them to ACL injury also creates excessive force on the patellofemoral joint • Increases women’s risk of patellofemoral subluxation • Women have an increased Q angle (17 degrees vs. 14 in men), which places them at greater risk

Other Knee Injuries • There is some controversy about the relative impact of the Q angle, which is measured statically when the athlete is at rest • May not accurately reflect active alignment • Incidences of patellar and knee dislocation do not differ by sex • These injuries always result from significant impact rather than the repetitive trauma that leads to patella subluxation

Ankle/Foot • Sex differences in the neuromuscular control of landing mechanisms also affect foot and ankle loading • This variable loading mechanism is thought to underlie the increased risk of 5th metatarsal fractures and Achilles tendon ruptures in men • Overall, men sustain more ankle sprains than women • Yet in specific sports, such as basketball, women are 4 times more likely to sustain type 1 ankle sprains

Ankle/Foot • Sex hormones do not seem to play a role in women’s propensity for ankle sprains • One of the most common pathologies of the foot is hallux valgus, a painful syndrome caused by lateral deviation of the great toe • Women are 2x as likely to have hallux valgus • The pathogenesis is complex but seem to be related to wearing shoes with a small toe box

Upper Extremity • Almost no data compares male and female athletes’ upper extremity injury rates • Upper extremity injury rates appear to reflect the kinesthetics and motor tasks associated with particular sports and their attendant risks • Sports involving repetitive overhead throwing motion (softball, baseball) consistently demonstrate high incidence of shoulder or elbow injury

Case • A 17-year-old woman who is right-hand dominant presents to the ED with obvious right shoulder deformity • She was pitching a softball game and suddenyl felt her shoulder “lock” • Since then, she has been holding her arm close to her side, adducted, with her shoulder externally rotated

Clinical Questions • How should you approach the work up in this patient? • What are the sex-specific elements in diagnosis and management that you should consider?

Shoulder • Fewer sex-specific injuries have been reported for the shoulder than for the knee • The shoulder is the most commonly dislocated joint • Traumatic dislocations are more common in men and demonstrate unidirectional instability • Atraumatic dislocations are more common in women with multidirectional injury patterns

Shoulder • Shoulder instability (including dislocation and subluxation) occurs 2.64 times more frequently in men than women • The shoulder is a complete ball and socket joint • Multidirectional instability is characterized by global laxity of the glenohumoral joint and is believed to be more prevalent in women

Shoulder • Female athletes are thought to have greater glenohumoral instability because their shoulders demonstrate more anterior glenohumoral laxity, less anterior joint stiffness, and more joint hypermobility

Shoulder • Women have decreased proprioceptive responsiveness in their shoulder joints • This leads to slowing of the reactive contraction of supporting muscles • Increased risk of structural damage • Shoulder joint laxity is also asymmetric in both sexes • It is not known whether this plays a role in injury risk for either sex

Shoulder • Most rotator cuff injuries suffered by overhead throwing athletes involve articular-sided partial-thickness tears of the rotator cuff • Caused by acute tensile overload, repetitive microtrauma, or both • This pattern of injury is common found at the junction of the infraspinatus (IS) and supraspinatus (SS) tendon insertions

Shoulder • As women age, the risk of rotator cuff injuries involving the IS and SS tendons increases • The most common etiologies of rotator cuff-related pain or injury in both men and women are subacromial impingement syndromes or repetitive microtrauma • This type of injury is much more common in women, especially women aged 55-59

Elbow • Most elbow injuries in athletes are due to repetitive overuse from overhead throwing or elbow weight-bearing sports (e.g., gymnastics) • The biomechanics of throwing often lead to a constellation of elbow injuries referred to as “valgus overload syndrome”

Elbow • Injuries include ulnar collateral ligament sprains or tears, common flexor tendon inflammation or tear, ulnar neuritis, and osteoarthritic changes of ulnohumeral joint • Because of the excessive stress placed on the elbow during the overhand pitching motion of baseball (as opposed to softball) severe elbow injuries, such as UCL tears, are more common in male athletes

Hand and Wrist • Contact injuries in sports such as ice or field hockey or lacrosse can result in fractures of the hand or wrist • Overuse injuries to the wrist are common in gymnastics, golf, weightlifting, racquet sports, and bicycling • Studies have found wrist pain incidence in gymnasts to be as high as 73% • In gymnastics, the upper extremity becomes a weight-bearing limb

Hand and Wrist • The differential diagnosis in chronic wrist pain in any athlete includes: • Triangular fibrocartilage tears • Ulnar impaction syndrome • Dorsal wrist ganglion • Dorsal wrist capsulitis • Carpal instability

Hand and Wrist • This constellation of injuries appears to be sports specific • No consistent data demonstrates sex-based differences in incidence or prevalence of these hand and wrist injuries

Musculoskeletal Pain Syndromes • In 2004, 13.8% of the 110 million ED visits were directly attributable to a primary musculoskeletal disorder • More than 1/3 of these visits were semi-urgent or non-urgent • Patients with chronic neck or low back pain who have no inciting trauma, systemic symptoms, or neurologic deficits do not require acute evaluation or intervention

Musculoskeletal Pain Syndromes • Chronic regional pain syndrome (CRPS) is an occasional sequela of orthopedic trauma, including fractures and crush injuries • Can also be seen after minimal injuries, including needlesticks • Patients present with pain out of proportion to the inflicting injury

Musculoskeletal Pain Syndromes • Patients can present at any time after their event • The cause of pain in CRPS has not been elucidated • Treatment is challenging • CRPS is much more common in women • Prevalence ratio of 4:1 females:males

Musculoskeletal Pain Syndromes • Contractures are a permanent tightening of soft tissue caused by fibrosis of ligaments, tendons, and muscles • Examples of contractures include: • Depuytren’s(palmar fascia)* • Ledderhose (plantar fascia)* • Adhesive capsulitis (glenohumoral joint capsule)** *More common in men **More common in women

Case • A 17-year-old woman has been training for the past 6 months to make the varsity high school track team • She has been running 6-7 miles per day, 6 days a week, and biking on the 7th day • She has not changed her diet and eats as much as she did before she started training • Her parents report she is strict about limiting her fat intake

Case • She presents with a 4-week history of progressive right leg pain that started at the end of one of her runs • The pain now occurs as soon as she starts running and is there even when she walks • Physical exam reveals bony point tenderness along the mid-shaft of the right tibia • No warmth or erythema

Sex & Gender in Acute Care Medicine