Kyphosis exists in nearly everyone’s upper spine in various degrees, but too much outward curve—sometimes called a “hunchback” or “dowager’s hump”—can reduce movement range of motion and increase the risk of some joint disorders and diseases. Like other types of postures, such as lordosis and scoliosis, many manual therapists and personal trainers encounter clients or patients with kyphosis and may suggest different types of treatments and care.
While posture does play a role in contributing back pain, shoulder pain, hip pain, and other types of musculoskeletal pain, the significance of posture may be exaggerated by both healthcare and fitness professionals, which makes patients and clients pay for treatments that have little to no effectiveness. This article examines the nature of kyphosis and pain and what the scientific literature says about treatment effectiveness and efficacy for kyphosis.
Kyphosis is the excessive outward curvature of the upper spine, which is also known as hyperkyphosis or thoracic kyphosis. Some research finds that the “normal” range of curvature of the thoracic spine falls between 20 to 40 degrees. This is measured by using the Cobb angle, which takes the most tilted vertebra in the highest and lowest kyphotic curve.
Oftentimes, some clinicians compare kyphosis vs. lordosis as a way to see if there are any relationships between the two types of posture for back pain, hip pain, and other types of joint pain. While there is some evidence that supports this idea, there are many variables among each person that makes predictions and treatments challenging.
Types of kyphosis
Different types of kyphosis have different origins and characteristics, which should be considered when seeking treatment.
There are two types of congenital kyphosis. Type 1 is the failure of formation of the posterior arch of the vertebrae and the spinal canal where the spinal cord and cerebral fluid pass through. Type 2 is the failure of separation of the anterior section of two vertebrae where they fuse together.
Although congenital kyphosis is uncommon compared to other types of kyphosis, it has a higher risk of developing neurological problems at an early age. A 1999 study of 112 subjects with congenital kyphosis found that 10 subjects at an average age of 14 had compression at the spinal cord that led to “spontaneous neurological deterioration.” One 28-year-old subject developed spastic paraplegia, which is the progression of weakness and stiffness in the legs.
A 2015 case study from India of an 18-month-old boy found that he developed congenital kyphosis because he was missing two vertebrae in his thoracic spine (T6 and T7). His mother noticed a “swelling” in his upper back when he was six months old, even though he was normal at birth and later developed normal walking and other motor skills. In this case, the researchers from the Mahatma Gandhi Institute of Medical Sciences concluded that such “growth deficits of the centrum during late stages of chondrification and ossification” as the child develops and grows, which may cause complications in movement later in life.
Postural kyphosis often develops during adolescence and adulthood. In most cases, the spine is normally developed but the curvature is exaggerated. This may be caused by a number of factors, such as chronic sitting or standing posture, accidents, stress and other psychosocial issues, and pain.
Scheuermann’s kyphosis usually develops during early puberty where the curve is noticeable between T7 and T9 and sometimes at T10 to T12. Although the hardening of the endplates of the thoracic segment may contribute to kyphosis, hereditary factors may also be contributors. Even so, there is still some dispute about how much hereditary factors play a role in developing Scheuermann’s kyphosis.
A large 2011 study of more than 11,000 pairs of twins in Denmark found that there is almost a 75% chance that Scheuermann’s kyphosis is hereditary with men having lower heritability rate than women. The researchers cautioned that some studies may “overrepresent” monozygotic twins and concordant pairs.
Another study in 2015 covered 27 different hospitals and research centers across Europe with more than a total of more than 4,400 men and 5,600 women. About 8% has Scheuermann’s kyphosis with the highest prevalence in the U.K., Germany, France, and Sweden and the lowest prevalence in Hungary, Slovakia, and Poland. The researchers found that bone density of the spine and hip is not a significant factor for developing Scheuermann’s kyphosis and neither was gender. They emphasized that future research should look at “new genetic and environmental determinants of this disease” beyond just X-rays and structure.
Kyphoscoliosis is a hybrid of both kyphosis and scoliosis where there is excessive curvature on both the sagittal plane and frontal plane. The prevalence of this condition varies in different countries and populations.
In the U.S., about 1 in 1,000 people have mild kyphoscoliosis and 1 in 10,000 people have a severe version. In a 2011 Turkish study of more than 1.7 million people in the Turkish Armed Forces who applied for military service between 2009 to 2011, about 0.4% of this population had kyphoscoliosis (about 7100 people). However, this huge sample is entirely young men and does not represent other populations, such as older people, women, and civilians.
Cervical kyphosis, also known as “military neck,” is an uncommon condition where there is no or almost no lordotic curvature of the cervical spine. This can cause a reduction in range of motion in neck flexion and extension. While this may cause some concern for people to seek treatment for cervical kyphosis, some evidence indicates that it is not strongly correlated with neck pain.
Because there are several types of kyphosis, this article focuses on thoracic kyphosis.
Classification of kyphosis
While there has been a classification system of lordosis since around 2005, there is not a stand one for thoracic kyphosis. In 2018, a group of researchers from Ganga Hospital in Coimbatore, India, started a classification system based on the curvature of the upper spine and the integrity of the anterior and posterior structures of the thoracic vertebra. Led by Dr. Shanmuganathan Rajasekaran, the team analyzed 180 X-rays and records of patients who required osteotomy and used 76 of those patients as part of their prospective study.
They classified three categories of kyphosis with each category having one or more sub-groups:
- Type IA: spinal column has no abnormalities with enough disc space to allow normal mobility and flexibility.
- Type IB: spinal column has no abnormalities with some segments of the vertebrae fused together.
- Type IIA: spinal abnormalities in the anterior part of the vertebrae.
- Type IIB: spinal abnormalities in the posterior part of the vertebrae.
- Type III: spinal abnormalities in both parts of the vertebrae with kyphotic curvature of equal to or less than 60 degrees (A), more than 60 degrees (B), or “buckling collapse” (C).
Spinal abnormalities in the anterior section refer to the loss of bone, disc, or both. The posterior part has more issues, including loss of function due to facet joint dislocation or loss of ligaments and bone.
In 2020, 12 spine surgeons from six different Asian countries independently examined the kyphosis classification system by evaluating 30 sets of X-rays, computed tomography scans, and magnetic resonance imaging scans on SurveyMonkey. Most of them were able to classify the extremes of the classification (Types IA, IB, 3C) but not so well on the remaining ones.
Causes of kyphosis
Besides the factors of congenital kyphosis and Scheuermann’s kyphosis, there are other internal and external factors that can affect the development of postural kyphosis.
Spina bifida is a birth defect where the neural tube, a structure that develops into the baby’s brain, spinal cord, and other neural tissues, does not develop fully or fails to close while in the womb. The most severe type of spina bifida is myelomeningocele, where there is a fluid-filled sac in the upper spine with nerves from the spinal cord inside it.
If this is not treated early in life, people with this condition would likely adopt a hunchback posture to avoid pain. Surgery to treat myelomeningocele has many complications yet it may improve thoracic kyphosis for some patients.
Osteogenesis imperfecta is a rare genetic disease that makes bones break easily with no apparent reason or causes. Similar to the character “Mr. Glass” that actor Samuel L. Jackson plays in the 2000 film “Unbreakable,” people with osteogenesis imperfecta produce too little or low-quality type 1 collagen.
About 40% to 80% people who have this condition have some sort of spinal deformities with kyphosis, scoliosis, and kyphoscoliosis being the most common, due to the “collapse” of the vertebral column.
Age is another factor that increases the risk of having kyphosis, likely because of various diseases and lifestyles, such as osteoporosis and being sedentary due to illness and disability.
A group of American and Iranian researchers reviewed the literature (1955-2016) behind the potential causes and clinical effects of kyphosis. They find that thoracic kyphosis is not caused by any single factor, rather, each person has different contributors to the posture. These include degenerative disc disease, genetic factors, injuries and accidents, and weakness in the back extensor muscles from muscle atrophy and/or weak electrical signals in the muscles and nerves.
Cancerous tumors may contribute to getting kyphosis via compression of the nerves in the spinal column and other physiological processes as the tumor develops and grows in the vertebrae. Symptoms include hip pain and back pain, tenderness to the affected area when touched, and pathological fractures. These may cause some people to adopt a kyphotic posture in response to pain as well as psychological stress.
Kyphosis and pain
Most mild forms of thoracic kyphosis are not not life-threatening or inhibit many people from living an independent life. Some people may, however, seek preventive treatments to delay the onset of kyphosis and its implications. While kyphosis and other types of postures, like anterior pelvic tilt and posterior pelvic tilt, can contribute to back pain and neck pain, scientific evidence shows that their role may likely be much smaller than many clinicians and patients believe.
A 1994 study of 610 women (ages 65 to 91) found that those with higher degrees of kyphosis had no greater risk of back pain or disability than those with less kyphotic posture.
“However, kyphotic women had no greater back pain, disability caused by back problems, or poorer health. This cross-sectional study suggests that kyphosis is associated with decreased [bone mineral density] and loss of height but does not cause substantial chronic back pain, disability, or poor health in older women,” the researchers reported.
Among children and teenagers, Dr. Torulf Widhe from Huddinge University Hospital in Sweden examined 116 children’s posture and spinal mobility at ages five and six. Ten years later, he was able to follow up with 90 of them. On average, he found that the kyphotic curve had increased by an average of six degrees.
Like the study with older women, higher kyphotic and lordotic angle correlated with reduced shoulder and spinal mobility. However, low back pain “was reported by 38% of the children at the age of 15-16 years, but back pain was not related to posture, spinal mobility or physical activity,” Widhe reported in 2001.
A 2016 systematic review found that thoracic kyphosis “may not be an important contributor to the development of shoulder pain,” but when the kyphotic angle is reduced closer to normal range, there is more range of motion in the shoulders. Out of the ten studies, four had a low risk of bias, three had moderate risk, and three had high risk. However, these findings are from single-session studies and have not been reliably replicated.
“Even if the studies had reported significant differences in thoracic kyphosis between groups, it would not have been possible to establish whether the thoracic hyperkyphosis preceded the shoulder symptoms or if the thoracic hyperkyphosis was a postural adaptation to shoulder pain,” lead researcher Eva Barrett and her colleagues wrote.
“The scope of these designs can only provide evidence on the immediate effects of changing thoracic kyphosis on shoulder symptoms and/or provide information regarding the prevalence of thoracic hyperkyphosis in groups with and without pain.”
In 2007, researchers Sanne T. Christensen and Jan Harvigsen from the University of Southern Denmark evaluated 54 qualified studies on the relationship between the sagittal plane curvature of the spine and back. Pooling data from more than 20,700 subjects, they found “insufficient evidence for an association” between spinal curves–including kyphosis and lordosis–with low back pain, symptomatic degenerative lumbar disc disease, disc herniation, upper back pain, headaches, bone mass loss, and breathing disorders.
As recent as March of 2020, The Journal of Biomechanics published a systematic review of systematic reviews that attempts to find a relationship between spinal postures or physical activity and low back pain. A team of researchers from Australia and Germany sifted through thousands of reviews from early 1990 to mid-2018. They included 41 systematic reviews with 11 of them including a meta-analysis. These research examined various factors, including standing, sitting, “awkward spine postures,” bending and twisting of the spine during movement, spinal curvature, and whole body vibration.
Based on three meta-analyses and two systematic reviews of spinal posture and low back pain, they concluded that there is some evidence of an association between the two but only for a short period of time and the “findings are not consistent.”
Because these studies have different methods of examining the evidence, the results are “conflicting.” The researchers explained that those analyses examined posture with radiographs and the definition of posture was “narrowly defined,” the result was that there was some association. Non-invasive measuring techniques, however, found no association.
Since systematic reviews and meta-analyses are supposed to be objective and the highest level of scientific evidence in research, the authors said these reviews they did “seems helpful to no one that a simple consensus is not available.” Thus, they concluded that while some postures may expose some people to risk getting low back pain, “there is no simple, clear link to [low back pain].”
Like most types of pain, there are no cookie-cutter treatments or a “one-cause” theory to explain why stuff hurts. Thus, the treatment for kyphosis would depend on the type, severity, and individual health factors, such as age, gender, health history, and behavior. This section reviews some of the major findings for each treatment and should not be used for self-diagnosis or treatment. Always consult with a qualified medical professional to find the best treatment for you.
For Scheuermann’s kyphosis, there is some evidence that supports its usage can reduce the curvature of the upper spine. In a review published in 2009, researchers Weiss, Turnbull, and Bohr found that there are no studies at the time that compare patients with a back brace and those without one. It is possible that this set up would be unethical because such studies would deny patients with kyphosis a potentially successful treatment.
Most studies that they cited showed improvements in reducing the kyphotic curvature. In a 1974 U.S. study in Minneapolis, Minn., 75 out of 223 patients who completed the trial had an average of 40% improvement in kyphosis and a 36% improvement in lordosis. Scoliosis did not affect the outcome.
About 12 years later at the same testing location, the same researchers followed up with 120 out of 274 patients who wore the back brace since the beginning of their diagnosis and treatment. They found that 76 of them showed improvements since the beginning, 24 patients had worsened, and ten of them had no changes.
Seven of the 24 patients who had worsened had a surgery for kyphosis before the study. Ten of the patients had inconsistent use of the back brace in which two of them had improvements while the others had worsened.
Photos of braces for Scheuermann’s kyphosis in the 1970s.
However, a back brace treatment would work better if Scheuermann’s kyphosis is detected earlier in life. Weiss et al. reported that back brace treatment is “almost always successful in patients with kyphosis between 55 degrees and 80 degrees if the diagnosis is made before skeletal maturity.” It would not likely to work if the angle is more than 80 degrees without surgery in patients with symptoms.
In 2014, researchers from the Clinic of Neurosurgery, in Izmir, Turkey, reviewed the literature of both conservative and surgical treatments for different types of kyphosis suggests that, for Scheuermann’s kyphosis, the back brace should be worn more than 20 hours a day for at least 18 months. When the postural correction is achieved, the time can be reduced to 12 to 14 hours a day. The researchers Onur Yaman and Sedat Dalbayrak did not report how long patients should continue to wear one afterwards, but from the previous long-term studies, it is likely that they would have to wear it for a few decades.
Exercise may help reduce the kyphotic angle. In a 2019 systematic review and meta-analysis of 10 randomized controlled trials, researchers from Universidad Católica de Murcia in Spain found that exercise has “a large, statistically significant, effect of exercise improving thoracic kyphosis angle” but not so much for lordosis. Strengthening exercises are likely to be more effective than stretching alone, which should be done two to three times a week for eight to twelve weeks to see any significant improvements.
Because this is the first systematic review and meta-analysis of this topic, the researchers pointed out that there are many differences in how the experiments were done, such as how the angle of the postures were measured, which may influence the actual outcome if the angles were measured consistently instead. The sample sizes were small in some of the trials, and there is also risk of publication bias. This review may apply primarily to postural kyphosis.
Surgery should be done to correct kyphosis if it is symptomatic and severe, such as Type III kyphosis. Yaman and Dalbayrak suggests surgery “should be considered for symptomatic patients when the thoracic kyphosis exceeds 80 degrees and thoracolumbar kyphosis exceeds 65 degrees.” Other considerations for surgery include failure of conservative treatments and “rapid curve progression.”
They identified a few indications for surgery.
- Postlaminectomy kyphosis: Surgery should be considered for patients with several compressions or tumors in the cervical spine. Patients with cervical lordosis are at higher risk of developing postlaminectomy kyphosis than those without such severe curvature.
- Post-traumatic kyphosis: Accidents, injuries, and other types of physical trauma can cause fractures, neural damage, and other problems in the spine. Yaman and Dalbayrak wrote that the goal of surgery is “to remove the existing neurological compression and bring the sagittal balance back to normal range.”
- Ankylosing spondylitis: This is one of several types of inflammatory rheumatic diseases. This condition affects the entire spine and sometimes other joints, including the sacroiliac joint, knee, and hips. The goal of this surgery is to correct the “chin-brow vertical angle) to allow patients to look straight ahead.
- Congenital kyphosis: For this type, surgery is a bit more complicated because the patients are mostly young children about five years or younger. Fusion of the posterior aspect of the spine can control the rate of changes of kyphosis as the child grows. They warned that paraplegia might develop because of a decrease of blood supply to the spinal cord during spinal extension and compression.
- Neuromuscular kyphosis: Causes of this condition include neuropathic and injury to the spinal cord, which include cerebral palsy, spinal cord injury, and syringomyelia. The goal of surgery is to “restore spinal balance, increase the respiratory capacity, and relieve pain.”
(This is not a substitute for medical advice from a qualified healthcare professional. Consult with your physician for options for your personal needs.)
Should I still learn how to fix kyphosis?
Other than severe forms of kyphosis that would restrict movement, exacerbate back pain and other types of pain, and reduce your quality of life, you may not necessarily need to “fix” your posture. Remember that many factors contribute to the pain experience, as summarized in the biopsychosocial model of pain. Some people may have a slouched posture, but that does not necessarily mean they have disability or inhibited independence, as demonstrated in previous population studies.
Because strength exercises may help reduce the kyphotic curve in the long run, it probably would not hurt to do regular back and shoulder exercises. The analgesic effect of exercise may also alleviate some musculoskeletal pain, one of many positive side-effects of exercise.
Since there is a lack of a strong association between pain and posture, a better alternative may be to seek activities that you enjoy doing regularly without or with minimal pain and discomfort. Managing psychosocial factors, such as anxiety, sleep quality, and social connections may also help alleviate pain.