These are the main diseases that affect bone tissue in humans.
The skeletal system allows us human beings to enjoy freedom of movement, posture and relationship with the environment from a mechanical perspective. This structural conglomerate is made up of 206 different pieces, a figure that is not negligible if we factor in the weight and height of our species.
Thus, the skeleton represents a total of 12% of the weight of the adult individual. In a 75-kilogram person, this corresponds to 9 kilograms of bone structures. To put this figure in perspective, the nerve command center (the brain) weighs an average of a kilo and little.
There is no doubt that the skeleton allows our existence as we know it today. After all , what would our species be if we couldn’t stand upright? Unfortunately, there are a number of diseases of the skeletal system to take into account throughout the life of the adult individual.
It should be noted that in this space we are going to focus on purely bone diseases, that is, they mainly affect bone structures. Pathologies such as osteoarthritis, gout or pseudogout can lead to bone damage, but affect the cartilaginous structure in its early stages. Here we present the main diseases of the bone system purely linked to the bone tissue.
4 diseases of the skeletal system: our structural base endangered
First of all, it is necessary to note that musculoskeletal diseases and disorders are much more common than might initially be expected. The world health organization (WHO) throws up a series of interesting figures regarding the subject:
- Musculoskeletal disorders are the leading cause of disability worldwide, with low back pain being the type most represented on Earth.
- Between one in three and one in five people suffer from a painful and disabling osteoarticular or muscular condition.
- They represent the highest proportion of persistent painful conditions (without taking into account carcinogenic processes).
- Up to half of the cases are related to underlying pathologies, that is, they are multimorbile disorders.
From birth to 20 years of age, the body synthesizes and adds more bone tissue than is degraded by cell death and wear. As time progresses, the body may not deposit bone as quickly as it is lost, leading to various complications from a bone point of view. Although it is true that the elderly are the age group that most experience this type of pathology, they are not the only ones. Here are the most common diseases of the skeletal system.
Osteoporosis is the most common type of bone disease. It occurs when the body breaks down more bone tissue than it can replace, which weakens the bones and promotes injury and fracture. In Spain alone, this disease is blamed for 500,000 fractures and 800,000 hospital stays per year. Furthermore, it is estimated that by the age of 79, 40% of women suffer from lumbar osteoporosis.
According to the World Health Organization, this pathology becomes official in the individual when he presents a bone mineral density (BMD) less than or equal to 2.5 standard deviation below the average bone mass of healthy 20-year-olds. This pathology encourages bone porosity (hence its name), but it is asymptomatic until the lesions occur.
In addition to age (an essential factor) there are other physical parameters that can promote the development of osteoporosis in the individual, such as bone cancer, some types of chemotherapy, family history, steroid therapies or prolonged periods of physical inactivity. It should be noted that women have a greater predisposition to this pathology, since after menopause there are imbalances in the levels of estrogen, a hormone that helps maintain bone density.
2. Osteogenesis imperfecta
We completely change the paradigm, because just as osteoporosis is a disease that responds to a physical deterioration in the individual and occurs in a relatively common way, osteogenesis imperfecta is caused by genetic mutations and is considered a rare disease.
90% of cases of this disease are caused by autosomal dominant mutations, and generally affects one in 15,000 newborns. This pathology is widely associated with a heterogeneous connective tissue disorder, mainly caused by poor synthesis and deposition of collagen (essential structural protein). Unfortunately, a person with osteogenesis imperfecta has a 50% chance of passing the causative gene to their son or daughter.
This pathology translates into bone fragility of a variable spectrum, which can manifest itself with abnormal bone breaks without apparent explanations. Just as osteoporosis is the queen of diseases of the bone system, osteogenesis imperfecta is considered an unfortunate exception.
3. Bacterial infections
Few people know that, as it is a tissue of a cellular and organic nature (no matter how many minerals it contains and how hard it is), bone can also be affected by microorganisms such as bacteria. This is the case of osteomyelitis, a pathology caused by the Staphylococcus aureus bacteria in 90% of infections.
We are dealing with pathogenic microorganisms settled in the bone tissue that have generally arrived by hematogenous route, that is, through the patient’s bloodstream. Once the bone is infected, the leukocytes enter it with the intention of fighting the bacteria, but along the way they release enzymes that end up corroding the bone tissue.
The pus produced by the infection spreads through the blood vessels that supply the bone, causing abscesses and preventing the arrival of nutrients and oxygen to the bone cells. As you can guess, this results in cell death and necrosis of the affected area. Of course, we are facing a pathology of a very unpleasant nature, which may also require antibiotic treatment for weeks or months due to its difficult elimination.
Finally, in the most severe cases, surgery may be required to remove the necrotized bone tissue. This is later filled with a prosthesis or graft, which stimulates the healing and recovery of the affected area. Like the rest of severe bacterial infections, the symptoms of bone infections are expressed in the first place with fevers, tremors and malaise on the part of the patient.
4. Bone cancer
As it could not be otherwise, it seems that no tissue with cell division is spared the possibility of developing a cancerous tumor. Bones are no different, as they contain living cells that can divide uncontrollably by abnormal mutations, leading to the dreaded bone cancer.
Osteosarcoma is the most common variant of this disease, and mainly affects young people between 10 and 19 years of age, since only 10% of those affected are over 60 years of age. This type of tumor is most commonly located in the bones of the arms, legs, and pelvis.
It should be noted that many types of cancer metastasize to the bone, but this does not mean that we are dealing with bone cancer as such. A malignant breast tumor that has spread to the skeletal system is a metastatic breast cancer, not a bone cancer in the strict sense.
As we have seen, in this space we have played all possible clubs. We have given the example of a “natural” bone disease, another genetically heritable and very strange, a third of infectious origin and the last due to a carcinogenic process.
Of course, this highlights the wide spectrum of diseases that can affect the skeletal system of the human being. In any case, the symptoms are more or less homogeneous in almost all pathologies: greater ease of fracturing of the bones or possible pain and swelling located in the affected area is observed.
- Bone cancer, cancer.org. Collected on September 8 at https://www.cancer.org/es/cancer/cancer-de-bone/deteccion-diagnostico-clasificacion-por-etapas/senales-sintomas.html
- Cramer, JA, Gold, DT, Silverman, SL, & Lewiecki, EM (2007). A systematic review of persistence and compliance with bisphosphonates for osteoporosis. Osteoporosis International, 18 (8), 1023-1031.
- Bone Diseases, MedlinePlus.gov. Retrieved September 8 from https://medlineplus.gov/spanish/osteogenesisimperfecta.html
- Gutiérrez-Díez, MP, Molina Gutiérrez, MA, Prieto Tato, L., Parra García, JI, & Bueno Sánchez, AM (2013). Osteogenesis imperfecta: new perspectives. Rev Esp Endocrinol Pediatr, 4 (160), 75-85.
- Osteoporosis, cancer.net. Collected on September 8 at https://www.cancer.net/es/asimilaci%C3%B3n-con-c%C3%A1ncer/efectos-f%C3%ADsicos-emocionales-y-sociales-del-c% C3% A1ncer / management-of-side-effects-f% C3% ADsics / osteoporosis
- Musculoskeletal Disorders, World Health Organization (WHO). Retrieved September 8 at https://www.who.int/es/news-room/fact-sheets/detail/musculoskeletal-conditions#:~:text=Los%20trastornos%20de%20este%20tipo,sist%C3 % A9mic% 2C% 20as% 20la% 20rheumatoid arthritis% 20.