Medical Guidance: Professor He Yiting, Rheumatology Department, Guangdong Hospital of Traditional Chinese Medicine
When discussing ankylosing spondylitis, most patients immediately think of bamboo-like spinal changes. However, beyond stiffness in the axial spine and limb joints, there exists a silent "invisible killer"—osteoporosis—that quietly follows those with ankylosing spondylitis.
Case Study: Bathing Leads to Fracture?
Du Lin, a 40-year-old man with nearly 10 years of ankylosing spondylitis, experienced only occasional morning back pain and paid little attention to it.One Sunday while traveling for work, he took a shower in his hotel room. As he stood up, the bathtub was unexpectedly slippery. He stumbled suddenly and fell heavily onto the edge of the tub, feeling a dull ache in his lower back... The next day, he went to the hospital. Doctor: "You have a fracture!" Du Lin: "What? You can fracture just from taking a shower?" Doctor: "Look at the X-ray. L4-L5, a stress fracture.Look here too—your osteoporosis is extremely severe!" Du Lin exclaimed, "What?! I have osteoporosis?! Premature aging?!"...
Osteoporosis doesn't exclusively affect the elderly; patients with ankylosing spondylitis are also prime targets for this condition.
What is Ankylosing Spondylitis?
Ankylosing spondylitis (AS) is a progressive chronic inflammatory osteoarthropathy primarily affecting axial joints like the spine, sacroiliac joints, and hips. It's characterized by new bone formation, spinal stiffness, and sacroiliac joint osteophytes, leading to spinal deformity, joint pain, and disability.Osteoporosis (OP) is a recognized major complication of AS, potentially causing spinal fractures and progressive spinal destruction even in early, mild stages. Recent research indicates that 40%-60% of AS patients worldwide develop varying degrees of osteoporosis concurrently with spinal and sacroiliac joint ankylosis.This occurs because localized bone proliferation is accompanied by excessive systemic bone loss. Consequently, osteoporosis associated with systemic inflammation poses a silent threat even in younger patients, significantly increasing fracture risk.
What are the symptoms of ankylosing spondylitis?
Primary symptoms: pain, tenderness, swelling, and functional impairment.
Distinctive features: deformities, crepitus, and abnormal mobility.
Associated changes: short stature, scoliosis, or kyphosis. Patients with longer disease duration should be particularly vigilant.
Why are AS patients prone to osteoporosis?
AS patients exhibit a high incidence of osteoporosis. Reduced bone density in the lumbar spine and femur often appears during youth and middle age, or in the early to mid-stages of the disease. This leads to complications such as spinal fractures, kyphotic deformity, and neurological impairment, severely impacting quality of life.However, the exact pathophysiology of AS-related OP remains incompletely understood. Contributing factors include gender, treatment methods, hormonal imbalances, disease duration, and reduced physical activity.
Bone density testing: Single-energy X-ray absorptiometry (DXA) and dual-energy X-ray absorptiometry (DXA). The former is simpler and used for screening; the latter is more accurate and serves as the gold standard for diagnosis.
Laboratory tests: Complete blood count, urinalysis, calcium and phosphorus levels, alkaline phosphatase, sex hormones, PTH, P1NP, CTX...
How is ankylosing spondylitis treated?
Current clinical therapies include: realignment, immobilization, functional exercises, and osteoporosis treatment. Medications such as active vitamin D, bisphosphonates, calcitonin, estrogen, and parathyroid hormone can partially improve osteoporosis symptoms.
For ankylosing spondylitis patients, osteoporosis and heterotopic ossification are like twin sisters—intertwined and inseparable. While widespread osteoporosis occurs, ossification of soft tissues and new bone formation already develop around the spine.How should bone changes in ankylosing patients be addressed? Let's hear what Traditional Chinese Medicine (TCM) has to say!
TCM's Dual Approach to Causes
Ancient TCM texts describe conditions like "tortoise-back wind," "bone bi," "kidney bi," "hunchback," "severe stoop," "back stoop," and "bamboo-joint wind"—all resembling modern-day ankylosing spondylitis.
The kidneys store essence and govern bone marrow production. When kidney qi is deficient, bones become dry and marrow becomes depleted. Bones lose their nourishment, leading to bone damage, erosion, and atrophy—manifesting as joint destruction and osteoporosis.Medical Forest Corrections states: "The kidneys store essence, essence generates marrow, marrow generates bones—thus bones are the union of the kidneys; marrow is the product of essence... When marrow is strong, bones are strong."Thus, kidney deficiency with essence depletion and marrow deficiency is the primary cause of osteoporosis. Additionally, the spleen is the foundation of acquired constitution and the source of qi and blood generation. Spleen deficiency leads to insufficient transformation and transportation, causing inadequate nourishment of bone marrow—this is the secondary cause of osteoporosis.
The Governor Vessel is one of the Eight Extraordinary Vessels, running along the middle of the back and governing all yang meridians of the body."When the Governor Vessel is diseased, the spine stiffens and bends backward." Kidney deficiency with insufficient essence leads to hollow marrow cavities, making one susceptible to external pathogens—especially cold pathogens. When the Governor Vessel is invaded, yang qi cannot open and close properly. Cold stagnates in the Governor Vessel, causing tendons and vessels to contract and stiffen, resulting in spinal rigidity that cannot be extended. This manifests as spinal ossification and even ankylosing changes.Additionally, prolonged bi syndrome with phlegm-stasis obstructing collaterals—where obstruction causes pain—is another key factor in persistent stiffness and unrelenting pain. Thus, the pathogenesis of "kidney deficiency with cold in the Governor Vessel" effectively explains the seemingly contradictory changes of bone loss and bone formation in ankylosing spondylitis, while also encompassing the full spectrum of skeletal alterations observed clinically.
Herbal Therapy: Strengthening the Du Meridian and Tonifying the Kidneys
The pathogenesis of ankylosing spondylitis involves kidney-Du yang deficiency and deep invasion by cold pathogens. Professor He Yiting of our hospital's Rheumatology Department, a disciple of Professor Jiao Shude—the foremost authority on treating bi syndrome in China—has innovated upon classical principles. Guided by Professor Jiao's "tonify the kidneys and strengthen the Du" approach, she has achieved significant therapeutic efficacy in treating ankylosing spondylitis.For over a decade, Director He Yiting has led her team in dedicated research on ankylosing spondylitis, masterfully applying the "Tonify Kidney and Strengthen Du" method to treat patients from across the country.This method combines multiple Chinese herbs including Dipsacus asper, Psoralea corylifolia, Epimedium, Drynaria fortunei, Notopterygium, Angelica pubescens, Saposhnikovia divaricata, processed Ephedra, and Atractylodes lancea. It achieves the effects of tonifying the kidneys, dispelling cold, warming the Du Meridian, strengthening tendons, invigorating blood circulation, and fortifying bones.
Clinical efficacy data demonstrate that the Kidney-Strengthening and Du-Channel-Fortifying Formula not only effectively controls symptoms, reduces or eliminates inflammatory activity, and improves osteoporosis, but also significantly increases bone density, regulates bone metabolism, enhances joint function, controls disease progression, and improves quality of life and long-term outcomes. Furthermore, it has led to noticeable radiographic improvements in bone spur formation in some patients before and after treatment.It is disclosed that Guangdong Hospital of Traditional Chinese Medicine has treated hundreds of ankylosing spondylitis cases using integrated TCM protocols with remarkable efficacy. Additionally, data indicates that the Kidney-Strengthening and Du-Channel-Fortifying formula effectively prevents bone loss and regulates bone metabolism, thereby achieving optimal control and adjustment of bone changes in AS patients.Director He Yiting emphasized that the "Kidney-Strengthening and Du-Channel-Fortifying Approach" provides personalized treatment plans for ankylosing spondylitis patients. It simultaneously inhibits bone ossification progression and bone loss, preventing bone changes from developing in either direction. Instead, it guides bone changes toward a positive trajectory of strengthening and fortifying bones, offering distinct therapeutic advantages.