Joint diseases are one of the most common causes of disability in old age and the consequences of joint injuries in professional athletes, which manifest themselves decades after the injury.
The general term for such diseases is osteoarthritis.
The market for drugs to treat it is currently one of the largest in terms of sales volume.
Main thoughts:
Official recommendations from health authorities for the prevention of joint diseases include maintaining a normal body weight, regularly engaging in physical exercise, and avoiding joint injuries.
Note: physical exercise serves both as a means of preventing joint diseases and a potential cause of their occurrence.
If everything is more or less clear regarding elderly people, then young and middle-aged individuals, especially those leading an active lifestyle, should be concerned about at least a few reasonable questions:
- what kind of sports to engage in (and is it even possible) to avoid harming the joints?
- how to protect oneself from joint diseases?
- what to do when the degenerative process has already begun and pain hinders sports activities?
The most common solution to these questions is the intake of medications for the treatment and strengthening of joints and ligaments (or chondroprotectors), which promise restoration and strengthening of cartilage in the joints and pain relief.
For active and healthy individuals, such prevention allows for reassurance and the continuation of their favorite sports, while for those already suffering from joint pain, it offers hope for recovery.
The aim of this article is to understand the causes of joint diseases (osteoarthritis), whether athletes are at a higher risk of injury, and if so, which sports are the most dangerous in this regard, how to protect the joints from degenerative processes in the form of osteoarthritis, and if it has already developed, how to treat it.
In most cases, joint pain in athletes and elderly people is osteoarthritis
Osteoarthritis (or arthrosis, osteoarthrosis, degenerative arthritis) is a general term for degenerative-dystrophic diseases of the joints, characterized by damage to the articular cartilage and changes in the structure of the bones, leading to pain and inflammatory processes in the joints, bone deformation, and ultimately, impaired mobility.
Osteoarthritis is one of the most common health problems in the modern world 1.
It is most often perceived as an issue for adults and the elderly.
However, some factors may predispose to its onset at a young age: genetics, excess weight, joint injuries, gender, race, professional activities (athletes, workers in heavy physical labor) 2.
Osteoarthritis clearly shows an age dependence: in the USA, it occurs in 7% of the population under 44 years old, in 29% of those aged 45-64, and in 63-50% of those over 65 12.
Among young patients with osteoarthritis, men are predominant, while among the elderly, women.
Osteoarthritis is the most common joint disease in both the elderly and athletes. It is a general term for a group of degenerative-dystrophic diseases in which the articular cartilage is damaged and the bones are deformed.
Anatomy of the Joint and the Mechanism of Osteoarthritis Development
To understand the causes of joint diseases in athletes and the elderly, as well as to comprehend the origins of the market for drugs to treat these diseases (chondroprotectors), it is necessary to take an excursion into the anatomy of the joint and understand what happens during their injury.
A joint is the place where bones connect. It consists of a capsule filled with fluid (synovial), into which the ends of the bones are “inserted,” “dressed” in cartilage.
Articular cartilage is composed of 80% water, with the remaining 20% being collagen and other protein molecules 1.
Synovial fluid acts as a lubricant, similar to oil in an engine. The cartilage at the ends of the bones serves as a damper that absorbs load on one side and reduces friction on the other.
Under load, the fluid in the joint cartilage slowly moves, effectively redistributing the load.
Moreover, the slower the load is applied, the more time there is for such redistribution, and the lower the likelihood of damage.
Conversely, the greater the load and the higher the speed of application to the joint, the higher the likelihood of injury 20.
This is key to understanding which sports are the most dangerous in terms of joint injuries and the development of their diseases in the future: intensive weight-bearing exercises, especially when performed with improper technique.
The greater the load on the joint and the higher the speed of application, the higher the likelihood of injury. Sports in which joints “work” according to this scenario are the most dangerous in terms of their injury and the development of osteoarthritis.
If we look at cartilage under a microscope, we will see cells called chondrocytes, placed in a matrix of collagen fibers, the space between which is filled with large molecules – proteoglycans.
Chondrocytes are mini-factories for producing the building material for cartilage. Thanks to their activity, the structure of cartilage is renewed: they create collagen and elastin fibers, as well as proteoglycans.
Proteoglycans are large molecules, the central element of which is hyaluronic acid, to which so-called glycosaminoglycans (chondroitin, heparin, keratan) are attached via protein bonds 42.
Proteoglycans fill the space between collagen fibers. They act as a connecting force in joint tissues and are responsible for filling cartilage with fluid: their structural components “attract” water molecules.
Water in the space between collagen fibers somewhat pushes them apart, creating mechanical tension. Collagen fibers resist this pressure, increasing the stiffness of the structure 15.
In addition, proteoglycans form a kind of reservoir for nutrients and growth factors. They connect with collagen fibers and, by nourishing them, make them stronger 15.
Cartilage has one important feature: it lacks blood vessels. This complicates the entry of nutrients for their renewal and recovery in case of damage.
The basic structural components of cartilage penetrate them only through diffusion. This means that their concentration in the surrounding joint tissues must be very high 42.
In the case of joint damage due to osteoarthritis, complex changes occur in its structural elements (bones, joint capsule, cartilage), but the most critical are the changes in the structure of cartilage.
At the first stage, the metabolism in cartilage cells is disrupted, leading to damage to the collagen matrix. At this point, the cartilage becomes inflamed and loses its ability to dampen physical load.
The thickness of the cartilage gradually decreases, the ends of the bones “become exposed,” leading to their deformation and pain.
The two most popular today for the treatment and prevention of joint diseases – chondroitin and glucosamine – are structural components of joint cartilage.
Joint injuries – the primary cause of osteoarthritis development
Under the same conditions, the likelihood of a joint injury in an athlete is lower than in an ordinary untrained person.
However, any joint damage can trigger a process of gradual degeneration, even if it is subsequently used normally 20.
It has been proven that ligament or meniscus injuries in the knee joint result in osteoarthritis in 50% of cases after 10-20 years, characterized by joint pain and mobility impairment 21,22.
“Even minor joint injuries are not dangerous, as the body knows how to heal them. However, when the damage is serious, exceeding the capacity of the recovery mechanism, the injury can easily lead to osteoarthritis.” – says Professor Alan Silman, a medical expert in an interview with the BBC news agency 13.
Due to the fact that there are no nerves in cartilage, the presence of damage can remain hidden from the athlete for a long time, predisposing them to even greater complications of joint disease due to ongoing and, most likely, progressive load 23.
The fact that there is pain in the joint in the absence of nerve endings also indicates that pain is a consequence not only of damage to the joint cartilage.
As will be shown below, some athletes are at a higher risk of joint injuries than others.
Risk factors include the type of sport, body weight, muscle mass (strength of the muscular framework), and genetics. There is a direct correlation between body weight and the likelihood of developing osteoarthritis 24.
Sumo wrestlers and American football players, for whom body weight is one of the defining “working” parameters, have a high predisposition to joint injuries and the development of degenerative diseases in the future.
According to some data, ligament and meniscus injuries in the knee joint lead to the development of degenerative osteoarthritis in at least 50% of cases after several decades.
Which athletes are more susceptible to joint disease (osteoarthritis)?
Finnish scientists conducted an interesting study aimed at determining which types of physical exercises are the most traumatic for the knee joints and are more likely to cause the development of osteoarthritis in the future 4.
To this end, they examined 117 professional athletes aged 45-68 for knee joint damage.
The study involved athletes from the following sports: 28 long-distance runners, 29 football players, 29 weightlifters, and 29 shooters.
As a result, osteoarthritis of the knee joint was found in:
- 3% of shooters;
- 29% of football players;
- 31% of weightlifters;
- 14% of long-distance runners.
Football players had the highest incidence of osteoarthritis of the tibiofemoral joint (between the femur and the lower leg) – 26%, while weightlifters (including bodybuilders) had the highest incidence of patellofemoral joint osteoarthritis (between the kneecap and the femur) – 28%.
Thus, among athletes, the highest risk of developing degenerative joint diseases is found in football players and weightlifters (bodybuilders).
The lowest risk, despite some apparent illogicality, is among representatives of cyclic sports – runners (who may also include cyclists).
These conclusions are supported by other studies: for football players 5-7,10, for weightlifters 6, for runners 6,8,9.
Moreover, despite the fact that in most cases osteoarthritis is preceded by joint injuries, some studies indicate that the risk of osteoarthritis in football players is 10 times higher than that of the general population, even in the absence of injuries 11.
Statistical data also confirm a significantly higher incidence of osteoarthritis among professional athletes compared to non-athletes of the same age group 18.
Research shows that cartilage destruction in the joint occurs under a force of 25 MPa or higher.
In sports such as running and jumping, where joints are actively engaged, the load on them is less than 25 MPa and the likelihood of cartilage damage is low 19.
It is evident that one of the most injury-prone sports is bodybuilding. Here, the likelihood of joint damage is proportional to the weights the athlete works with and the intensity of the exercises performed.
The most dangerous sports in terms of joint diseases are football and weightlifting (bodybuilding), while the least dangerous is running.
Causes of Joint Diseases (Osteoarthritis)
With some caveats, the following statement is valid: the more physically active a person is, and the more time they spend engaging in sports, the higher the risk of developing joint problems 1.
One of the confirmations of this fact is the results of a study conducted by scientists on active military personnel in the USA, which showed a significantly higher likelihood of developing joint diseases (osteoarthritis) among military personnel compared to the same age group of the general population 3.
The risk factors in this study were shown to be gender, age, race, type of armed forces (level of physical activity), and rank.
At the same time:
- the risk of osteoarthritis in women is 20% higher than in men;
- among soldiers over 40 years old, the incidence of joint diseases is 19 times higher than in young people under 20;
- among African American soldiers, the risk is significantly higher than among “whites” and other nationalities.
The cause of osteoarthritis in older adults and athletes (or military personnel) is quite obvious: natural wear and tear of the joints. In the former, it is due to age; in the latter, due to high physical activity and injuries.
With age, cartilage loses its physical properties and becomes more “soft.” It loses its ability to recover, and changes occur in its structure: the connections between individual collagen fibers strengthen, which increases stiffness in the joint 42.
Also, with age, muscle mass in the body decreases. Muscles and ligaments relieve the load on the cartilage by stabilizing all the converging elements in the joint; their weakening facilitates the displacement of these elements relative to each other, which increases the load on the cartilage and accelerates its destruction. It is clear that in the case of excess body weight, which is characteristic of older adults, all these processes are accelerated.
In the study mentioned in the previous section 4, scientists also compiled a list of the most likely causes of joint diseases (osteoarthritis) in ordinary people:
- knee joint injuries;
- high body mass;
- heavy physical labor (proportional to the number of years);
- work that requires kneeling or squatting;
- playing football (as a hobby).
According to scientific research, genetics plays a very significant role in the development of osteoarthritis. Some estimates suggest its role is around 40-65%.
Scientists say that several genetic disorders may be responsible for the onset and development of osteoarthritis, which manifest in defects in the structure of cartilage tissue and metabolic disturbances in the joint 42.
At the same time, experts note that there is still much that is unclear regarding the understanding of the causes of osteoarthritis.
The main causes of degenerative joint damage are injuries, a high level of physical activity (sports, physical labor), during which joints are subjected to high loads, and genetics.
Can you exercise with osteoarthritis? Opinions of doctors and scientists
Not only can you, but you should.
“Overall, physical exercise is beneficial for joint health because cartilage and bones need load,” said Professor Alan Silman, a medical expert, in an interview with the BBC news agency 13.
“Swimming, cycling, walking – an example of a good combination of exercises for the joints for the treatment and prevention of arthritis.” – Tom Saw, a doctor in sports medicine 13.
Why?
They engage large muscles, which is beneficial for weight loss (reducing body mass); they are aerobic, which is good for heart and vascular health; they do not overload the joints, and the movements are anatomically correct.
Dr. Simon Till, a consultant in sports medicine at the Royal Hallamshire Hospital in Sheffield:
“It is much more important to be active throughout the day than to go to the gym. For example, walk more instead of using a car or bus, work in the garden.”
For those who have already developed osteoarthritis, it is recommended to lift lighter weights and engage in aerobic exercises.
At the same time, Dr. Simon Till notes that although some chondroprotectors may be useful for preventing and treating osteoarthritis for both professional athletes and amateurs, it is much more important to engage in sports that do not overload the joints.
Experts also emphasize the importance of warming up and stretching before training, which reduces the likelihood of joint injuries and subsequent development of osteoarthritis 13,14.
Reviews from doctors and experts on the treatment and prevention of osteoarthritis: “Physical exercises are beneficial for joint health… a good combination of exercises includes swimming, cycling, and walking… it is important to engage in sports that do not overload the joints… as well as to warm up and stretch before training“
Symptoms of Deforming Osteoarthritis of the Joints
A large number of people with structural changes in the joints do not feel any symptoms. However, the symptoms listed below are likely to indicate the progression of degenerative processes in the joints.
1 Pain
One of the most obvious signs is pain. However, pain is a rather subjective parameter and not very indicative for assessing the degree of joint damage.
Different people have different pain sensitivities: some calmly endure severe pain, while others cry at a slight bruise. With age, pain sensitivity increases 25.
This means that for young people and athletes with a high pain threshold, diagnosing joint injuries at early stages may be complicated.
Moreover, progress in sports subconsciously implies the ability to endure pain and act against it.
In bodybuilding, for example, it is believed that muscle growth occurs through pain. And everyone knows that fractures make bones stronger, at least at the fracture sites.
But the situation with joints is different. Pain in them, especially chronic pain, is a clear sign that “something is not right there.”
At the same time, joint pain in deforming osteoarthritis is usually dependent on physical activity: it may occur during or after physical exertion, and then gradually subside.
In the early stages of joint damage (osteoarthritis), pain may be episodic and appears one or two days after “active use” of the joint (such as during sports activities, for example).
In severe cases of osteoarthritis, the pain may become continuous.
Joint pain in deforming osteoarthritis, occurring during or after physical exertion, or constant – is one of the clear signs of degenerative joint damage
2 Impaired Joint Mobility
Poor joint mobility, especially in the morning after sleep, is another characteristic symptom of osteoarthritis.
Most often, the functionality of the joint “recovers” after half an hour or an hour after waking up and may be disrupted again after a period of rest.
The more osteoarthritis progresses, the more pronounced this symptom becomes.
3 Creaking and Cracking
Other signs of joint damage include sensations of cracking and creaking, as well as roughness of the joint surfaces during the movement of the corresponding limbs 1.
Signs of Osteoarthritis of the Knee Joint and Hand Joints
The American College of Rheumatology published signs for diagnosing osteoarthritis of the knee joint in 1986 based on the analysis of a large number of joint disease cases 26:
| Signs of Osteoarthritis of the Knee Joint |
|---|
| Pain in the knee joint and at least three symptoms from the following list: |
|
Similar criteria were later described for diagnosing osteoarthritis in the hand joints 27 and hip 28.
| Signs of Osteoarthritis of the Hand Joints |
|---|
| Dull pain in the hand, poor mobility, and 3 or 4 of the following symptoms: |
|
* 10 selected joints are the second and third distal interphalangeal joints (between the second and third phalanges of the fingers (counted from the base of the finger)), the second and third proximal interphalangeal joints (between the first and second phalanges of the fingers), and the first carpometacarpal joints of both hands (the junctions of the wrist bones with the bases of the metacarpal bones at the base of the palms)
** Metacarpophalangeal joints are the junctions of the fingers with the palm
How to treat osteoarthritis? Joint disease prevention
The treatment of osteoarthritis pursues two goals: to reduce pain and restore joint functionality.
1 Physical exercises
For a long time, doctors have recommended physical exercises for the treatment of osteoarthritis both for pain relief and for improving joint functionality 29,30.
However, in some studies, the long-term effect of exercises has been questioned by researchers 31, but was confirmed by the results of a meta-analysis of scientific studies on this issue 32.
Based on the analysis of more than 8000 cases of osteoarthritis, researchers showed that types of sports that increase muscle strength (including strength training in water), flexibility, and aerobic capacity are the most effective for treating joint diseases of the lower extremities (osteoarthritis of the knee and hip joints) 32.
Here, “treatment” refers to the improvement of joint functionality and the elimination of pain.
Scientists note the need for an individual approach in choosing the type of exercises and developing a training program, as different exercises affect different aspects of the disease.
For example, professional athletes may be recommended strength training exercises, as they reduce pain, allowing them to return to training and competitions faster 1.
At the same time, the effect of aerobic exercises for them is not very obvious.
Engaging in certain types of sports (for muscle strength, flexibility, aerobic capacity) is the first recommended treatment by doctors and scientists for osteoarthritis of the lower extremity joints. Scientific studies confirm the effectiveness of exercises in alleviating joint pain and improving their functionality.
2 Joint medications and chondroprotectors
Usually, physical exercises are combined with the intake of non-steroidal joint medications to reduce inflammatory processes in the joints and pain, as well as to stimulate cartilage recovery 33.
They can be effective in the early stages of osteoarthritis; however, with prolonged use, some of them may cause digestive disorders, while the effectiveness of others has very weak scientific support.
The goal of taking chondroprotectors is to restore or prevent the destruction of joint cartilage. Many of them, even the most popular ones, also lack unequivocal scientific confirmation of effectiveness.
The effectiveness of most non-steroidal drugs for relieving pain and inflammatory processes in the joints, as well as for restoring cartilage, lacks unequivocal scientific confirmation.
3 Bandages, Supports, Orthoses
Bandages, supports, and orthoses are designed to limit movements in the joints in unnecessary directions, facilitate movements in necessary ones, and maintain distances between the structural elements of the joints.
Their use is important, as osteoarthritis leads to distortion in the positioning of the joint components and impairment of their functionality 34,35.
The effectiveness of using bandages, supports, and orthoses is scientifically supported and is common practice among athletes. They help reduce pain, correct biomechanical disturbances in the joint, and shorten recovery time.
There is a wide variety of bandages and supports available on the market, and just like with exercises, their selection for each specific case should be individualized under the guidance of a physician.
4 Corticosteroid Injections in Joints
Steroid injections have anti-inflammatory effects and are often used for quick pain relief in the joints.
They are relatively safe for short-term use and are frequently utilized by professional athletes for rapid restoration of joint functionality during competitions 36.
However, it is important to keep in mind that some types of steroids have a toxic effect on cartilage cells (chondrocytes) and therefore cannot be used for extended periods 37.
Steroid injections in joints are used for pain relief only for a short time. Steroids are toxic to cartilage cells.
5 Diet
Some scientific studies indicate that diet can have a significant impact on the progression of osteoarthritis and its symptoms, particularly pain.
Interesting results come from the following study on the impact of a low-carbohydrate diet on joint pain in osteoarthritis 41.
In a 12-week experiment, 21 individuals aged 65-75 with knee joint diseases and severe pain participated.
The participants were divided into three groups: the first – ate as usual, the second – was on a low-fat diet (800-1200 kcal per day), the third – on a low-carbohydrate diet (only 20 g of carbohydrates per day, but could eat as much as they wanted).
Results: the degree of perceived joint pain after the experiment was significantly lower in those on the low-carbohydrate diet compared to the other two groups.
Interestingly, the scientists named reasons for this effect. One of them is quite obvious – a significantly greater reduction in body weight. It is worth noting that low-carbohydrate diets are among the most effective for weight loss and beneficial for health.
Another less obvious reason is the reduction of free radical activity in the body, which is the cause of many diseases and related inflammatory processes and pain.
The low-carbohydrate diet significantly activates the protective function of antioxidants, which neutralize free radicals.
A low-carbohydrate diet can be an effective method for treating and preventing joint diseases (osteoarthritis), particularly – reducing joint pain
6 Surgical Intervention
Surgical intervention is a last resort and is applied in cases where previous methods have failed, and severe pain and dysfunction of the joint make its use impossible.
Arthroscopy is the primary surgical procedure recommended for osteoarthritis.
The effectiveness of the procedure is highly controversial; some studies indicate that it is minimal 38,39.
Arthroscopy is mainly performed for diagnosing joint injuries and treating painful tears and other meniscus injuries.
A recent study published in the New England Journal of Medicine shows that about 60% of such tears are completely painless and resolve without symptoms, which generally questions the appropriateness of performing arthroscopy to address such injuries 40.
Moreover, in the case of poorly performed surgery, the harm from it may outweigh the questionable benefits.
Other surgical interventions for treating knee osteoarthritis include osteotomy of the tibia, partial and total joint replacement.
Arthroscopy of the knee joint is a primary surgical procedure that is prescribed for serious joint damage in osteoarthritis. Its effectiveness is highly questionable: some experts claim that the harm it may cause can outweigh the benefits.
Conclusion
Most often, joint diseases or osteoarthritis are the result of past joint injuries.
Osteoarthritis is one of the leading causes of disability in old age, and the market for its treatment and prevention (chondroprotectors and analgesics) is one of the largest today.
Recommendations from doctors and scientists for the prevention of joint diseases in athletes and ordinary people, as well as for the treatment of osteoarthritis, can be summarized as follows:
- if you have joint injuries, do not delay visiting a doctor: scientific data indicate that joint injuries often precede osteoarthritis;
- normalize your body weight: this will help reduce the daily load on the joints;
- change your eating habits: experiment with low-carbohydrate diets, which are very effective for weight loss, beneficial for health, and may reduce the sensation of pain in the joints;
- engage in sports regularly: strengthening muscles and developing flexibility reduces the likelihood of joint and ligament injuries and also aids in recovery;
- do not overload your joints: certain types of physical labor (e.g., tile laying) and sports (e.g., bodybuilding) create increased stress on the joints and increase the risk of their diseases.
