Hyperkyphosis in older persons

INTRODUCTION — Hyperkyphosis is excessive curvature of the thoracic spine, commonly known as the "dowager's hump." Although it is also referred to simply as kyphosis, the term kyphosis is meant to describe the normal sagittal convexity, or forward curvature, of the thoracic spine which can range from normal to abnormal. Kyphosis tends to progress with age [1].

The evaluation and treatment of hyperkyphosis is challenging due to the lack of standardized diagnostic criteria and evidence-based treatment options. Exercise programs, spinal orthotics, and other interventions have been studied that may help delay the progression of age-related kyphosis. However, stronger evidence of efficacy with improved clinical outcomes is needed prior to widespread use of many of these interventions.

This topic will focus on the etiology, evaluation, and management of hyperkyphosis in older adults. Hyperkyphosis in children and adolescents is discussed separately. (See "Back pain in children and adolescents: Causes".)

PREVALENCE — There is no widely accepted definition of hyperkyphosis, and therefore the prevalence of hyperkyphosis in older persons is not precisely known. Estimates range between 20 and 40 percent among community-dwelling individuals aged ≥60 years [2-4].

The prevalence of hyperkyphosis increases with age in all adults, with the greatest change in the angle of kyphosis occurring among women age 50 to 59 years [5]. In a study of 154 adults aged 60 and older living in Italy, kyphosis increased by about 8 to 9 degrees per decade [6].

ETIOLOGY AND PATHOGENESIS — The vertebral bodies and intervertebral discs are the major anatomical structures that contribute to spinal contour (figure 1). Thus, any process that affects either supporting structure can lead to hyperkyphosis. Deformities that result in anterior wedge-shaped vertebra will accentuate the angle of kyphosis. As with other age-related conditions, hyperkyphosis occurs as a result of multiple contributing factors.

●Vertebral fractures – Vertebral bodies account for the majority of height in the spinal column, and it is commonly believed that age-associated hyperkyphosis mainly results from vertebral fractures. Patients with vertebral fractures have worse kyphosis compared with those without vertebral fractures [7-9]. However, only 36 to 38 percent of older persons with the worst degrees of kyphosis have underlying vertebral fractures [7,10]. Nonetheless, large observational studies report that with each vertebral fracture, kyphosis increases by about 3.7 to 3.8 degrees [11-13]. Modeling studies have demonstrated that wedge-shaped vertebral fractures increase biomechanical stress and compressive load on adjacent vertebrae [14,15].

Unlike limb fractures, vertebral fractures represent a continuum of deformity. There is no defined cut-point that distinguishes a vertebral fracture from another deformity that is not due to osteoporosis. In fact, achieving an acceptable level of radiologic agreement in defining a vertebral fracture is challenging. Vertebral compression fractures are discussed in detail separately. (See "Osteoporotic thoracolumbar vertebral compression fractures: Clinical manifestations and treatment".)

●Low bone density – Multiple studies have demonstrated that low bone density, even in the absence of underlying vertebral fractures, contributes to worse kyphosis in older adults [12,16,17]. Greater rates of bone density loss have been associated with worse kyphosis progression in older women, and a lower trabecular bone score, reflecting cancellous bone quality of the lumbar spine, has been associated with hyperkyphosis in males [12,18]. It is hypothesized that low bone density may exacerbate the slight wedge shape present in normal thoracic vertebral bodies, in which the height of the anterior side of the vertebra tends to be shorter than the posterior side.

●Short vertebral height – Causes of vertebral deformity other than fractures or osteoporosis are collectively called "non-fracture" deformities. These deformities may be the result of developmental abnormalities with or without degenerative changes. The most common developmental hyperkyphosis is Scheuermann's disease, an inherited kyphotic deformity of the spine that usually occurs in early adolescence [19-21]. Scheuermann's disease is defined by a thoracic Cobb angle of >45 degrees with anterior vertebral wedging of three or more consecutive vertebrae, end-plate irregularity with Schmorl's nodes and disc space narrowing, and has an estimated population prevalence of 8.3 percent [22]. (See "Back pain in children and adolescents: Causes", section on 'Scheuermann (juvenile) kyphosis'.)

●Degenerative disc disease – The intervertebral discs in the thoracic spine range from 1 to 2 cm in thickness. With age, the discs can desiccate and lose height, and anterior wedging may occur. There is a significant association between degenerative disc disease and the degree of kyphosis [7,12,23].

●Postural changes – The postural configuration of the cervical, lumbar, and sacral spine may influence thoracic curvature [24]. Subjects with thoracic hyperkyphosis are more likely to have cervical or lumbar lordosis [25,26].

Postural flexibility, which decreases with age, likely contributes to hyperkyphosis. Compared with younger women, women aged 66 years and older had greater flexicurve kyphosis and were less able to actively correct their usual relaxed posture to an erect position [27]. Spinal proprioceptive sense also has been reported to impaired in older persons with hyperkyphosis defined as >50 degrees compared with those with kyphosis angles ≤50 degrees [28].

●Muscle weakness – It is unclear whether hyperkyphosis precedes or results from muscle weakness. Most [29-38], but not all [39-41], studies report an inverse correlation between muscle strength and hyperkyphosis. A study of 1172 older adults aged 70 to 79 years assessed spinal extensor muscle cross-sectional area and density using computed tomography (CT) and found that lower spinal muscle density was associated with hyperkyphosis (defined as >40 degrees) [42]. Data from 1087 participants of the Framingham Heart Study confirm that smaller thoracic trunk muscle area was associated with worse kyphosis by 3.7 degrees in women and 2.5 degrees in men, though loss of muscle density as ascertained by CT scan was not associated with kyphosis progression over an average of six years of follow-up [38]. However, using magnetic resonance imaging (MRI), another study of lumbar paravertebral muscle fatty infiltration in a small sample of 28 adults ranging in age from 55 to 84 reported that erector spinae fatty infiltration was significantly correlated with thoracic kyphosis [43]. Furthermore, they demonstrated that there was a positive correlation between muscle fatty infiltration and increase of kyphosis with ambulation.

●Intervertebral ligaments – With aging, intervertebral ligaments that provide stability to the spine are susceptible to loss of elastic tissue, calcification, and ossification [44,45]. Diffuse idiopathic skeletal hyperostosis (DISH) is diagnosed by the presence of ossification of the ligaments in the anterolateral thoracolumbar spine involving at least four contiguous segments, without evidence of intervertebral disc degeneration. Studies have found that older persons with DISH tend to have greater degrees of thoracic kyphosis [46,47].

●Genetic/metabolic conditions – Early-onset hyperkyphosis is often observed in inherited genetic conditions including osteogenesis imperfecta, Ehlers-Danlos Syndrome, Marfan syndrome, cystic fibrosis, mucopolysaccharidoses, spondylo-epiphyseal dysplasia, and Scheuermann's disease.

Age-associated hyperkyphosis is most likely a complex inherited trait. In a population-based cohort, investigators found that those who reported a family history of dowager's hump were more likely to have greater kyphosis [12]. A twin study comparing monozygotic and dizygotic older twin women reported a significant genetic influence on the degree of thoracic kyphosis, with a heritability estimate of 61 percent (95% CI 46-72) [24]. Analysis of data from the Framingham Study, based on CT images in over 2000 adults, estimated the hereditable component at 54 percent (95% CI 43-64%) [48].

Mouse knock-out and transgenic models suggest that hyperkyphosis may be a common physiologic phenotype that results from mutations involving genes important for DNA repair and delaying senescence. These knock-out mice develop early senescence and often suffer from pronounced hyperkyphosis [49-53]. In humans, it is commonly believed that poor posture can worsen kyphosis, but kyphotic mice demonstrate that gravitational forces may play a minor role in the development of hyperkyphosis, as mice spend their lives in a prone position.

●Other causes – Other causes of hyperkyphosis that arise in childhood include congenital kyphosis and neurofibromatosis. Later-onset causes can include spondylolisthesis, ankylosing spondylitis, spinal tuberculosis, post laminectomy syndrome, and other complications from spinal surgical procedures [54].

ASSOCIATED HEALTH CONSEQUENCES — The health conditions associated with hyperkyphosis are varied. The most important conditions include impairment of lung function, decreased functional capacity, and increased mortality.

Impaired pulmonary function — Several studies have shown that increasing kyphosis leads to modest, but predictable, declines in forced vital capacity, as well as other measures of pulmonary function [55-59]. In a study of 323 community-dwelling adults age 65 and older, those with hyperkyphosis were more likely to have restrictive ventilatory dysfunction (odds ratio [OR] 2.3, 95% CI 1.1-4.8), obstructive ventilatory dysfunction (OR 3.3, CI 1.7-6.5), and self-reported dyspnea (OR 2.5, CI 1.1-5.8) [60]. Another study of 56 patients found that, in addition to worse forced vital capacity and forced expiratory volume, those with a kyphotic angle ≥40 degrees had worse duration of exercise than those patients with <40 degrees [61]. Baseline kyphosis severity was associated with a greater decline in FEV1 in women but not in men, in a prospective study over 275 persons aged 50 to 79 years, followed for over 16 years [62]. The lack of effect in men may have been due to the small sample size (n = 82) and survivor bias because the men were more likely to smoke and had higher mortality than women during the time of the study (1970s to 1980s). (See "Chest wall diseases and restrictive physiology", section on 'Kyphosis and scoliosis'.)

Diminished physical function — Multiple observational studies suggest that hyperkyphosis is associated with poor physical function [3,30-32,34,39,40,63-70]. In studies that have examined muscle strength directly, most have demonstrated a significant negative correlation between kyphosis and back extensor strength [29,31,32,39] or grip strength [67]. Hyperkyphosis is also associated with worse physical performance functional measurements, including walking speed [3,65,66,68], the timed get up and go test [66,69], and the standing from a chair test [67,68,70]. Problems with daily functioning such as dressing oneself, cooking, and bathing have also been reported [63-65,67]. Three out of four prospective studies of kyphosis reported declining function over time, though one of the largest that included 1100 adults reported no differences in measured walking speed, chair-stand time, and grip strength after an average of 3.4 years of follow-up [71-74]. Notably, those 1100 adults were on average younger than those in other studies (mean age 61) and they had less severe kyphosis than reported in other studies.

Falls — It has been hypothesized that hyperkyphosis fundamentally alters balance, thus increasing fall risk [32,75,76]. However, several studies have not consistently demonstrated an association between various measures of balance and hyperkyphosis [33,77-79]. Differences in study results may stem from the wide age range of people studied (from just over 50 to 85) to differences in the kyphosis measures, balance assessments, and fall ascertainment methods used. Alternatively, it may be that with age-related increases in kyphosis, there are compensations in pelvic alignment that serve to stabilize the skeleton such that fall risk is not increased [80]. The association between thoracic kyphosis and falls, if present, appears to be minimal, although one study of 72 older community-dwelling persons who provided monthly communication regarding incident falls did report a twofold increased fall risk per standard deviation increase in kyphosis [81-83]. Another study of 1220 community-dwelling older adults that documented incident falls on a weekly basis for two years and found that the increased fall risk was only significant in those over the age of 77 [84].

Increased fractures — Hyperkyphosis is associated with thoracic vertebral fractures, and it is presumed that the fracture leads to hyperkyphosis [8,85-87]. However, with forward-bent posture, changes in gravitational loads may increase the risk of sustaining a spinal or other osteoporotic fracture.

In prospective cohort and case-control studies in older women, hyperkyphosis was associated with increased risk of fracture [88-91]. As an example, in a study of 596 older women followed prospectively over four years, women with hyperkyphosis were at increased risk for future fracture (OR 1.7, 95% CI 1.0-3.0) compared with those without hyperkyphosis [90]. A larger study in older women found that a baseline measure of kyphosis was associated with a 50 percent (95% CI 1.10-2.06) increased risk of future non-spine fracture, and worsening kyphosis was also associated with an increased fracture risk [91]. Analyses were adjusted for age, bone mineral density, prior fracture, and prevalent vertebral fractures.

The greater the degree of kyphosis, the higher the biomechanical load on vertebrae, suggesting that older persons with hyperkyphosis would be at increased risk for vertebral fractures [15]. However, three large prospective studies report conflicting results. While all three did demonstrate that those with worse kyphosis were at increased risk for future vertebral fractures, only two out of three were able to demonstrate that the effect was due to the spinal curvature and not underlying baseline spine fractures (an established future fracture risk factor) [13,92,93].

Other health-related consequences — Age-related hyperkyphosis may be associated with other adverse health effects.

●Pain symptoms, particularly back pain, is associated with hyperkyphosis [8,63,94]. In addition, there are many case reports of associations between hyperkyphosis and insufficiency fractures of the sternum where patients tend to present with chest pain that is at first confused with that of acute myocardial infarction or pulmonary embolism [95,96].

●Multiple gastrointestinal problems including dysphagia, reflux esophagitis, hiatal hernia, Barrett's esophagus, and intrathoracic stomach have been associated with hyperkyphosis [97-101].

●The risk of pelvic prolapse and stress incontinence may increase with greater kyphosis [102-104].

●In one study examining osteoporosis and quality of life, patients with osteoporosis and self-reported postural changes had increased physical difficulty, made more adaptations to daily life, and had more fears about their future [105]. Women with postural changes and no osteoporosis had significantly more physical difficulty and lifestyle adaptations than those with a prior fracture and no postural changes, demonstrating that the ill effects of hyperkyphosis are not necessarily due to underlying fractures.

●Kyphosis may be associated with poor sleep health, although the effect may differ between women in men. In a study of older adults, only women with worse kyphosis reported shorter sleep duration (<7 hours) and were more likely to report regular use of sleep medications [106]. Similarly, in a study that included only older men, there were no associations between worse kyphosis and poorer subjective or objective sleep quality measures [107]. (See "Evaluation of sleep-disordered breathing in adult patients with neuromuscular and chest wall disorders", section on 'Kyphoscoliosis'.)

Increased mortality — Hyperkyphosis is associated with increased mortality in older adults [2,10,85,108]. Until recently, most have assumed that the degree of hyperkyphosis simply represents the severity of underlying vertebral fractures. However, in a prospective cohort of 610 women, each standard deviation increase in kyphosis was associated with an increased risk of all-cause mortality (relative risk [RR] 1.15, 95% CI 1.01-1.30) [108]. This association was adjusted for age, bone mineral density, and prior vertebral fracture, suggesting that low bone density and underlying vertebral fractures were not the only causes for the increased mortality risk. This study, and a smaller study in patients with end-stage kidney disease, also demonstrated that the combination of hyperkyphosis and vertebral fracture is an added risk factor for mortality [108,109].

EVALUATION — Unlike other geriatric syndromes, such as osteoporosis and incontinence, the hyperkyphotic phenotype is immediately obvious from appearance, making observation an important clinical tool (picture 1).

Most primary care clinicians do not have experience assessing the clinical and radiologic tests described in this section. Thus, it is reasonable to refer patients to a clinician with experience in treating hyperkyphosis (eg, physiatrist, rheumatologist, orthopedic surgeon) once hyperkyphosis is suspected on history and/or physical examination. As kyphosis is clinically apparent early in the disease process and likely takes years to progress, early recognition and treatment may help improve the health and quality of life of a substantial portion of the older population.

Measuring kyphosis — If hyperkyphosis is suspected, objective measurement of kyphosis is performed to determine severity.

In the sagittal plane, the normal spine contains three curves: the cervical region that is convex anteriorly, or lordotic; the thoracic region that is concave anteriorly, or kyphotic; and the lumbar region that is convex anteriorly, also lordotic (figure 1). The degree of kyphosis can be measured clinically or radiographically.

Clinical methods use devices such as the flexicurve ruler [1], goniometer [29], inclinometer [110], or Debrunner kyphometer (in which a protractor is applied to the upper back) (picture 2) [111]. Among these devices, the flexicurve ruler is the least expensive and relatively easy to use. Less precise but more practical clinical measures of kyphosis include: the distance from the occiput-to-wall [112], the number of 1.7 cm blocks between the head and exam table while lying flat with the neck in a neutral position (figure 2) [2], and qualitative visual measures [3,4].

The radiologic methods generally use lateral spine radiographs with either manual or computer-assisted calculation of an angle of curvature, termed the Cobb angle. The Cobb angle is measured by drawing perpendicular lines from two lines: (1) a line from the upper border of the vertebral body marking the beginning of the thoracic curve (commonly T4); and (2) a line from the inferior border of the vertebral body representing the interface between the thoracic-lumbar curves (commonly T12). The Cobb angle is then calculated as the angle of intersection of these perpendicular lines (figure 3). Although the Cobb angle was first developed to assess scoliosis angles on spinal radiographs, it was later modified to measure kyphosis and is considered by some to be the gold standard of kyphosis measurement [113]. Unless specifically requested, radiologists do not routinely calculate the Cobb angle of kyphosis from lateral spine radiographs. With artificial intelligence tools beginning to impact health care, work is underway to develop and validate computer-aided diagnoses of sagittal spinal curves, including thoracic kyphosis [114].

Defining hyperkyphosis — Defining hyperkyphosis is challenging as there are no standardized, age-adjusted reference ranges to distinguish between hyperkyphosis and normal age-related kyphosis.

In older adults, the mean kyphotic angle is 48 to 50 degrees in women [7,8,86] and 44 degrees in men [7] and continues to increase with age [1,6,7,25,87,115-125]. While there are no widely accepted thresholds for defining hyperkyphosis and many studies use different measurement techniques, several studies have used the cutoff of ≥40 degrees in older adults [61,126,127].

Ongoing large prospective cohort studies may provide longitudinal data to better define hyperkyphosis. One study found that a Cobb angle >53 degrees was associated with a 50 percent increased risk of future non-spine fracture compared with women with lower degrees of kyphosis, and another found that a Cobb angle ≥50 degrees was associated with increased rate of falls in those over the age of 77 years [84,91].

Assessing other conditions — All patients with hyperkyphosis require an evaluation for osteoporosis. This topic is reviewed in detail separately. (See "Screening for osteoporosis in postmenopausal women and men" and "Clinical manifestations, diagnosis, and evaluation of osteoporosis in postmenopausal women" and "Clinical manifestations, diagnosis, and evaluation of osteoporosis in men".)

If clinical parameters are used to measure kyphosis, a plain spine radiograph should be performed to rule out underlying osteoporotic vertebral fractures. Ideally, a musculoskeletal radiologist should read the film since interrater reliability in reading vertebral fractures is rather poor, even among skilled radiologists [128]. The radiologist should also assess for previously undiagnosed Scheuermann's disease, anterior wedge compression of the intervertebral discs, or other spinal pathologies.

MANAGEMENT — We suggest exercise-based interventions focused on the rehabilitation of postural abnormalities as first-line treatment for hyperkyphosis. There are no standardized management guidelines. Other treatments include spinal orthoses, postural taping, manual therapy, pharmacologic therapy, and surgery.

Patients without severe symptoms — Patients without severe symptoms should be offered exercise-based treatments. Examples of mild to moderate symptoms include difficulty lifting one’s head up, difficulty seeing forward while walking, and impaired balance. Although some patients may be asymptomatic due to lack of pain or overt functional impairment, signs such as the inability to lie flat (including on an examining table) identify patients who may benefit from treatments aimed at preventing disease progression.

Exercise-based interventions — We suggest exercise as an initial treatment, under the guidance of a physical therapist if possible. Exercise should focus on postural alignment, as well as flexibility and core strengthening, including the back extensor muscles. Once learned, exercises should be continued over the patient’s lifetime, with short daily practices.

If a physical therapist is not available to instruct that patient, the following exercises can be demonstrated in the clinician’s office for daily home practice:

●Have the patient stand up with their back and feet against the wall to obtain as upright a posture as possible, with their eye gaze straight forward. Once positioned correctly, teach them to engage the diaphragm for deep breathing to make them aware of their core abdominal muscles. Next, instruct them to take five deep breaths, paying attention to their posture so they can continue to practice good posture throughout the day.

Secondly, instruct the patient to raise their arms above their head and then into a cactus position, extending their chest upwards and forwards, and repeat the breathing exercises.

●Have the patient transition to an “all fours” posture on the floor, and instruct them to practice the cat-cow positions (alternating spinal rounding and extension). With the cow, take a deep breath, and with the cat, exhale. Repeat about five times (figure 4).

In the primary care setting, clinical response to exercise can be measured by having the patient return to the office to demonstrate the movements. The clinician can then record their own subjective impression of the ease of performance and flexibility, as well as elicit patient feedback.

There are increasing data to suggest the benefit of exercise in hyperkyphosis. Four systematic reviews that included from 10 to 28 intervention studies evaluated the effectiveness of exercise on hyperkyphotic posture. In the most comprehensive review and meta-analysis with GRADE assessment that included only older adults with kyphosis of at least 40 degrees, among 24 included studies, exercise or physical therapy improved kyphosis with moderate-certainty evidence and increased back extensor muscle strength and endurance with low-certainty evidence [129]. In general, a frequency of two to three sessions per week during an 8- to 12-week period has been shown to improve at least one measure of posture, although potential study biases (non-blinding and incomplete outcome data) limit the reliability of these findings [129-132]. In terms of adverse events, there was low-certainty evidence as to whether there might be an increased risk of falls, and only one study (not included in the systematic reviews) reported increased vertebral fracture severity and incident vertebral fractures among men who were randomized to receive machine-based isometric axial compression (IAC) training compared with high-intensity progressive resistance and impact training (HiRIT) [133].

At least seven randomized exercise trials demonstrate that exercise interventions in older adults may improve kyphosis by 3 to nearly 7 degrees, as determined by radiographic Cobb angle measurement or dual-energy x-ray absorptiometry (DXA) imaging [131,134-136]. Specific exercise interventions were performed two to three times weekly for three to eight months under supervision of a physical therapist and ranged from one-hour sessions of spinal strengthening and postural training to 30-minute HiRIT and impact loading exercises (dead lift, squat, and overhead press). Low-impact strength training exercises are not thought to be harmful in patients with osteoporosis. Two trials that included both sexes and persons with osteoporosis who participated in supervised HiRIT did not report any significant adverse effects [133,136].

For those without access to a physical therapist, digital technologies involving mobile phones and mobile apps are being developed and tested that deliver short instructional video clips (45 to 60 seconds long) on best posture and spinal strengthening. Pilot testing demonstrate promising results with improvements in kyphosis of up to 8 degrees, though randomized controlled trials are needed to confirm these initial findings [137].

Additional treatments

Spinal orthosis — There are a wide variety of flexible spinal orthoses (back braces) designed to improve posture [138-140]. In addition, spinal orthoses may facilitate stimulation of proprioception to improve unconscious muscle strengthening [141]. One study compared three types of trunk orthoses ranging from rigid to semi-rigid to soft thoracolumbosacral orthoses (TLSO) on the degree of kyphosis in older persons with osteoporotic hyperkyphosis. Because trunk orthoses may adversely affect balance and function, functional measures including forward reach test, timed up and go test, and posture stability were also assessed. While all three orthoses served to reduce the kyphosis angle, only the rigid orthosis adversely affected functional reach [142].

Two randomized trials have tested whether the use spinal orthoses in older women with osteoporosis has a favorable effect on either hyperkyphosis or back extensor muscle strength [143,144]. In one trial, the year-long use of a brace for 12 hours a day (not used in resting or sleeping positions) resulted in a decrease in kyphosis of seven degrees. In the other trial, in which participants wore a brace for at least two hours a day, there was a 27 percent improvement in back extensor strength at six months but no change in kyphosis. In a third randomized trial of a semi-rigid thoracolumbar orthosis involving 48 adults aged >60 years with kyphosis >50 degrees, compared with the control group, those assigned to wear the orthotic for two to four hours daily for three months demonstrated improvement in kyphosis of 14.8 degrees with associated improvements in back muscle performance [145].

Other orthoses — Based upon prior studies that demonstrate improvements in gait speed and low back pain, investigators postulated that a heel lift could increase the lumbar angle as well as improve spinal kyphosis and walking ability. In a small study of 33 older persons of mean age 78 with hyperkyphosis defined as >53 degrees, using a 10 mm heel lift significantly decreased the thoracic angle by about 7 degrees, improved the walking speed by 0.1 m/s, and increased step length by an average of 3 cm. Though a small study, consideration of using a 10 mm heel orthotic to improve posture is a feasible and affordable intervention [146].

Postural taping — Therapeutic spinal postural taping involves tape applied from the anterior aspect of the acromioclavicular joint, over the muscle bulk of the upper trapezius, and then diagonally towards and just past the spinous process of T6. The tape is applied bilaterally, intersecting at T6 (figure 5). In a study of therapeutic postural taping, control taping, or no taping in 15 women over the age of 50 with vertebral fractures, therapeutic tape significantly decreased kyphosis compared with control taping [147]. It is unclear whether the immediate effects of therapeutic taping lead to longer-term beneficial effects. Taping is usually performed by a physical therapist.

Manual therapy — Manual techniques including massage, mobilization, muscle energy, and myofascial release may potentially improve kyphosis, as suggested by a trial in women aged 18 to 30 years [148], but studies in older adults are not available.

Pharmacologic therapies — Few data are available showing benefit of pharmacologic therapies in treating hyperkyphosis. In the Fracture Intervention Trial of 4432 postmenopausal women with low bone density, those randomly assigned to alendronate had reduced height loss compared with those randomly assigned to placebo (7.0 versus 8.5 mm) [149]. However, in a secondary analysis of the Fracture Intervention Trial, there was no benefit of alendronate in delaying kyphosis progression over an average of 4.2 years [150].

A study that combined results from two randomized trials reported that treatment with strontium ranelate decreased progression in kyphosis index over three years compared with placebo (3.7 versus 4.7 percent, respectively) [92]. Kyphosis index was defined as the percentage ratio between the maximum depth of thoracic curvature and the height measured from the T4 to the T12 vertebrae. As the difference in kyphosis index progression was only 1 percent, the beneficial effect of strontium on delaying kyphosis progression, if present, is likely of minimal consequence.

Patients with severe symptoms — We define severe symptoms as those impairing breathing (restrictive lung disease), significant pain, or severe functional impairment.

Surgical interventions — We recommend not using surgical interventions unless patients have intractable pain, disability, significant pulmonary function impairment, or progressive neurologic deficits, as these interventions are associated with high rates of perioperative complications, including 13 percent for revision surgery, 16 percent for implant-related complications, 21 percent for medical complications, and 29 percent for proximal junctional kyphosis (PJK) reported in a 2022 systematic review and meta-analysis of adult spinal deformity surgery [151,152]. If surgery is performed, a posterior-only approach is recommended as it is associated with decreased blood loss and shorter surgical times compared with anterior or combined approaches. Techniques with reported success include pedicle screw fixation combined with Smith-Petersen osteotomies [153]. In the systematic review, surgical treatment for adult spinal deformities has increased linearly, with interbody fusions and three-column osteotomies becoming more common over time. Less invasive interventions such as vertebroplasty and kyphoplasty have not demonstrated long-term benefits [154-156]. The clinical diagnosis and management of vertebral compression fractures are reviewed separately. (See "Osteoporotic thoracolumbar vertebral compression fractures: Clinical manifestations and treatment".)

Prevention — Exercise and maintaining good posture have been suggested as measures to prevent hyperkyphosis [157,158]. However, there are no prospective studies or randomized trials evaluating their effects.

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Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topics (see "Patient education: Kyphosis in adults (The Basics)")

SUMMARY AND RECOMMENDATIONS

●Hyperkyphosis is excessive curvature of the thoracic spine that tends to worsen with age. Since there is no widely accepted definition of hyperkyphosis, the prevalence of hyperkyphosis in older persons is not precisely known. However, estimates range between 20 to 40 percent among community-dwelling elders. (See 'Prevalence' above.)

●Hyperkyphosis is associated with several adverse health conditions including thoracic pain, decreased pulmonary function, limited physical functioning, increased fractures, and increased mortality. (See 'Associated health consequences' above.)

●The degree of kyphosis can be measured clinically with devices such as a kyphometer or radiographically with plain film (figure 1 and picture 2). While there are no widely accepted thresholds for assessing hyperkyphosis, many clinicians consider ≥40 degrees the defining cutoff for hyperkyphosis. (See 'Evaluation' above.)

●In patients with hyperkyphosis, we suggest using an exercise-based treatment program focused on postural alignment, as well as flexibility and strengthening of back extensor muscles (Grade 2C). (See 'Exercise-based interventions' above.) There are limited data showing benefit of other treatment options, including spinal orthosis, postural taping, pharmacologic therapies, and surgery. (See 'Additional treatments' above.)