The increasing prevalence of obesity in the population has a pronounced effect on the progression of a broad spectrum of musculoskeletal disorders. Obesity is also associated with increased operative risks in the management of surgical procedures for musculoskeletal disorders (Amin et al., 2006). The prevalence of musculoskeletal disorders causing frequent pain is currently increasing. At the same time, the occurrence of second-degree obesity, that is, obesity with a body mass index BMI (35,0–39,9) (Anandacoomarasamy et al., 2008), is also increasing.
Obesity is associated with many musculoskeletal disorders in children and adults. Increased prevalence of obesity impacts reduced quality of life, linked to the economic costs required for proper healthcare and to the frequent chronicity of musculoskeletal disorders (Townsend, Scriven, 2014). On the basis of body mass index, the population can be divided into groups: undernutrition (below 18,5 kg/m2), normal weight (18,5-24,9 kg/m2), overweight (25-29,9 kg/m2), and obesity (over 30 kg/m2). Obesity can be divided into classes: class I (30,0-34,9), class II (35,0-29,9), and class III (>40,0) (Kozłowska-Wojciechowska, 1996). Patients diagnosed with obesity suffer from pain and discomfort, increased risk of injury, thermoregulation difficulties, and an increased risk of developing osteoarthritis and other diseases (Shultz et al., 2014). A study from 2006 by McTigue et al. stated that a patient's weight is an important modifiable risk factor for health risk in the development of musculoskeletal disorders. Mortality cases increase proportionally with obesity class. Patients with diagnosed third-degree obesity have an increased risk of mortality at disease onset compared with patients with a lower obesity class, overweight, or normal weight (McTigue et al., 2006).
Musculoskeletal disorders are defined as damage to the locomotor apparatus triggered by external influences, high biomechanical exposure, psychosocial and psychological factors. Disorders of the musculoskeletal system manifest as acute or chronic states, with pronounced pain symptoms and reduced physical performance (Lentz et al., 2019). Among the most significant risk factors that condition the risk of developing these diseases are age, sex, a sedentary lifestyle and the related insufficient physical activity, and especially anthropometric indicators such as body mass index. Weight gain considerably loads weight-bearing joints. Obese individuals are exposed to a higher risk of joint injury due to biochemical changes in the body associated with higher body weight during everyday activities. A lack of physical activity combined with increased body weight increases the probability of incorrect movement and physiological positioning of joints and muscles, while the risk of developing musculoskeletal defects rises (Faghri, Momeni, 2014).
Pediatric obesity and its impact on the musculoskeletal system
Regular physical activity is an essential factor for optimal growth and development of a child. The development of obesity in children is linked to a range of functional problems, including pain, discomfort and stiffness of lower limb joints, loss of muscle mass, and the occurrence of chest and spinal deformities. Obese children and adolescents are most often affected by gait deviations, deformities in the alignment of the lower limbs, and slipped epiphysis of the femoral head (Gettys et al., 2011). A high prevalence of musculoskeletal disorders such as lumbar hyperlordosis, acquired knee alignment deformity and knee hyperextension is seen to a greater extent in obese children compared with children with normal weight (O'Malley et al., 2012).
Orthopedic complications and physical activity contribute to pain and discomfort in individuals with obesity, which has a direct link to reduced motivation to perform physical activity and to increased body weight. Pediatric patients with obesity and chronic musculoskeletal pain have an increased risk of anxiety and development of depression (Gettys et al., 2011).
Podeszwa et al. in their 2006 study focused on determining the overall health status of obese children. They assessed presence of pain and the ability to participate in daily life activities and intense exercise. The study confirmed in girls with obesity aged 11 to 18 a significant reduction in musculoskeletal function and mobility with marked pain. Boys with obesity in the study showed a marked reduction in mobility, but without increased pain compared with boys with normal weight. The results indicated a higher prevalence of disability development in adulthood (Podeszwa et al., 2006).
Hainsworth et al. (2009) examined the health impacts in a population of obese children in whom pronounced chronic musculoskeletal pain was present. The results showed that in 48 % of obese children musculoskeletal pain is more frequently present than other types of pain, such as headache or abdominal pain. The study was based on the hypothesis that the combination of chronic pain and obesity has a negative effect on mobility and function of the musculoskeletal system. The research confirmed a mutual relationship between chronic pain, obesity, and level of physical activity. Lack of physical activity contributes to a negative effect, whereby overweight and obese children with existing chronic pain continue to reduce physical activity and exercise, potentially contributing to further weight gain (Hainsworth et al., 2009).
Obesity in adults and its impact on the musculoskeletal system
Body composition together with muscle mass plays a key role in functional fitness of movement in obese individuals. A high proportion of body fat negatively affects the fatigue resistance of the body. Clinical studies indicate that the obese population suffers from lower gait cadence and shorter step length, with a prolongation of gait cycle duration (Vaara et al., 2012). Patients with obesity suffer progressive loss of physical performance. This is expressed as weakness, fatigue and insufficient physical activity, which again contributes to further weight gain. Inflammatory and oxidative metabolic disorders due to excessive adiposity, together with catabolic changes in skeletal muscle proteins, lead to muscle mass loss and reduced physical performance (Reyes et al., 2016).
Osteoarthritis
Among the most common pathological changes of the musculoskeletal system in adults with diagnosed obesity are degenerative inflammatory joint changes. Excessive body weight alters the structure and function of knee cartilage, which directly affects the progression of osteoarthritis.
Osteoarthritis can be defined as a multifactorial disease that leads to dysfunction and complete joint alteration caused by joint degeneration (Brooks, 2002). Its symptomatology is marked pain, reduced mobility, which has a negative impact on quality of life. The pathogenesis is linked to excessive joint loading together with hormonal and biochemical dysregulation of the organism. Excessive body weight in individuals with obesity contributes to increased joint loading, resulting in a negative impact on joint function.
Weight reduction substantially affects clinical pain relief and can delay progression of structural joint damage (King et al., 2013). Increasing weight loads and damages joint cartilage beyond its biological capacity and causes degenerative changes. A risk factor for the onset of early-stage osteoarthritis directly correlates with an increase of only 1 kg of total body fat (Teichtahl et al., 2015).
The study by Misra et al. (2019) followed participants in a cohort study who showed increased risk for development of osteoarthritis. Using DEXA (dual-energy X-ray absorptiometry), participants were categorized based on body composition and the amount of muscle mass and fat. The study dealt with the relationship between body composition, amount of body fat, and risk of osteoarthritis development during the 60-month duration of the study. The analytical cohort consisted of 1653 individuals. A significant increase in osteoarthritis risk was observed in the group of obese women without clinical osteoarthritis at study start (Misra et al., 2019).
Hinman et al. in their study (2023) focused on comparing the influence of physiotherapeutic exercise and physical activity on improving condition in patients with diagnosed knee osteoarthritis. The qualitative study compared the effects of physical activity and exercise in a randomized sample of 26 patients. It observed pain symptom relief and improvement in movement function over 9 months. Study results confirmed the positive effect of physical activity on alleviating clinical manifestations of the disease (Hinman et al., 2023).
Sarcopenic obesity
Sarcopenic obesity is considered a clinical state in which, in patients with obesity, muscle tissue becomes infiltrated by adipose tissue, causing loss of bone and muscle mass. Age, sex, excessive alcohol intake and an inappropriately chosen poor-quality diet with low protein content are risk factors associated with increased risk of developing sarcopenic obesity (Pang et al., 2021). In skeletal muscle of patients with confirmed obesity, metabolic changes occur that negatively affect the function of muscle mass. Alterations of adipose tissue, skeletal muscle, and bone are closely interrelated, with vitamin D playing a key metabolic role in maintaining homeostasis and health of the musculoskeletal system (Liu et al., 2022). Vitamin D deficiency is a widespread global public health problem. One third of the world's population suffers from vitamin D deficiency, affecting more than 20% of the population in northern Europe, 30–60% of the population in western, southern, and eastern Europe, and up to 80% in countries of the Middle East (Lips et al., 2019). Inflammation and oxidative stress in cells are able to induce anabolic resistance in skeletal muscle, ectopic fat accumulation with fat infiltration. Infiltration leads to lipotoxicity and changes in muscle stem cells. Adipocyte differentiation, mitochondrial dysfunction, and growth of body weight with obesity development lead to reduced energy production, increased oxidative stress, functional limitations, and musculoskeletal complications (Barazzoni et al., 2018).
Currently, 19 % of the population is affected by sarcopenic obesity. The prevalence of sarcopenic obesity varies by population and its increase is primarily related to age despite physiological loss of muscle mass. Patients with diagnosed metabolic syndrome, excessive adiposity, and insulin resistance have double the risk of developing osteosarcopenic obesity. Other risk factors in the etiology of sarcopenic obesity include sex, excessive alcohol consumption, low calcium intake, and poor diet. Individuals exposed to excessive glucocorticoids due to Cushing's disease, patients with type 2 diabetes mellitus, kidney transplant recipients, and long-term anabolic steroid users are exposed to the risk of developing osteosarcopenic obesity. Patients recovering from severe COVID-19, due to treatment with high-dose steroids and increased adiposity, are also at risk of developing sarcopenic obesity. Individuals with osteosarcopenic obesity with increased visceral fat have a higher risk of fracture compared with individuals in whom subcutaneous fat predominates (Di Fillipo et al., 2022).
Discussion
Sufficient physical activity and an active lifestyle are especially important for children of all age groups and contribute to a higher probability of proper physiological development of motor skills. Reduced physical activity disturbs the development of basic movement abilities. The result is insufficient formation of motor skills needed for participation in everyday movement activities (Fisher et al., 2005).
Many studies show a significant impact of obesity on bone and joint health, especially the etiology of pathological states such as bone demineralization, deformation, and dysfunction associated with pain caused by structural changes in the organism. The study by Taylor et al. (2006), when examining orthopedic complications, reported a markedly higher prevalence of fractures in children and adolescent patients with overweight and obesity compared with the group of children and adolescents with normal weight (Taylor et al., 2006).
The study by De Sá Pinto et al. (2006) reports the occurrence of degenerative joint changes in patients with second- and third-degree childhood obesity based on BMI (body mass index) values. The results showed frequent cases of degenerative joint changes with pronounced pain and higher frequency of genu recurvatum (excessive extension of the knee joint) compared with the normal-weight population. The study indicates the presence of serious risk of musculoskeletal dysfunctions, deformities, and pronounced pain in patients with diagnosed obesity (De Sá Pinto et al., 2006).
Reijman et al. (2007), in a population cohort study, investigated the relationship between body mass index, incidence and progression of knee and hip osteoarthritis development. The study results confirmed the impact of overweight on the occurrence of knee osteoarthritis. A relationship between overweight and the etiology of hip osteoarthritis could not be demonstrated. Obesity in patients was associated with progression of knee osteoarthritis, while the relationship between obesity and hip osteoarthritis was not proven. Progression of osteoarthritis was assessed based on narrowing of joint space on radiographic imaging (Reijman et al., 2007).
Weight reduction substantially reduces pain and improves musculoskeletal function in obese individuals with diagnosed knee osteoarthritis. Gudbergsen et al. (2012) demonstrated in their study the effect of weight reduction on symptomatic relief of knee osteoarthritis in obese individuals, independent of the severity of joint damage. The study assessed 175 individuals with third-degree obesity and clinical knee osteoarthritis. Results were evaluated using MRI (magnetic resonance imaging) after 16 weeks of a prescribed low-energy diet. Patients achieved substantial weight loss, and 64 % of patients reported significant symptomatic improvement of the disease. Pain relief was associated with weight loss, yet no structural changes were observed. The results suggest the possibility of clinical improvement in patient condition with weight loss, despite pronounced knee joint degeneration (Gudbergsen et al., 2012).
Conclusion
Obesity has a pronounced effect on many disorders of the musculoskeletal system and reduced quality of life. Weight reduction is key to alleviating manifestations of musculoskeletal disorders. Obesity is associated with pain, joint dysfunction, and more frequent bone fractures. Progression of osteoarticular changes in the adult population with obesity leads to a need for long-term orthopedic therapy. The growing prevalence of obesity currently contributes to a greater societal burden, the development of chronic musculoskeletal diseases, and declining quality of life related to health and healthcare costs (Anandacoomarasamy et al., 2008).
Authors: *MVDr. Martina Tejová doc. MUDr. Kvetoslava Rimárová, CSc., mim. prof. prof. Mgr. MUDr. Erik Dorko, Phd., MPH, MBA***
The work is supported by KEGA 008UPJŠ-4/2020 grant Multimodal Technologies in Teaching Cardiovascular Risk Studies and Population Health Status for University Students Using Freely Available Software Applications and by KEGA 010UPJŠ-4/2021 grant Implementation of E-learning Preventive Interventions in the Education of Medical and Non-Medical Disciplines.
List of bibliographic references
AMIN, Anish K. – SALES, James D. – BRENKEL, Ivan J. 2006. Obesity and total knee and hip replacement. In Current orthopaedics. 1941-7551, 2006, 20, 3, 216–221.
ANANDACOOMARASAMY, Ananthila, et al. 2008. The impact of obesity on the musculoskeletal system. In International journal of obesity. 1476-5497, 2008, 32, 2, 211-222.
BARAZZONI, Rocco, et al. 2018. Sarcopenic obesity: time to meet the challenge. In Obesity facts. 1662-4033, 2018, 11, 4, 294-305.
BROOKS, Peter M. 2002. Impact of osteoarthritis on individuals and society: how much disability? Social consequences and health economic implications. In Current opinion in rheumatology, 1531-6963, 2002, 14, 5, 573-577.
DE SÁ PINTO, Ana L, et al. 2006. Musculoskeletal findings in obese children. In Journal of paediatrics and child health, 1440-1754, 2006, 42, 6, 341-344.
DI FILLIPO, et al. 2022. Vitamin D in Osteosarcopenic Obesity. In Nutrients, 2072-6643, 2022, 14, 9, 1816.
FAGHRI, PD – MOMENI, K. 2014. Musculoskeletal diseases, overweight and obesity, and aging workforce: how to encounter the problem. In Journal of obesity and weight loss therapy, 2473-7372, 2014, 4, 2.
FISHER, Abigail, et al. 2005. Fundamental movement skills and habitual physical activity in young children. In Medicine & Science in Sports & Exercise, 1530-0315, 2005, 37, 4, 684-688.
GETTYS, F Keith, et al. 2011. Obesity in pediatric orthopaedics. In Orthopedic Clinics, 0030-5898, 2011, 42, 1, 95-105.
GUDBERGSEN, H, et al. 2012. Weight loss is effective for symptomatic relief in obese subjects with knee osteoarthritis independently of joint damage severity assessed by high-field MRI and radiography. In Osteoarthritis and Cartilage, 1522-9653, 2012, 20, 6, 495-502.
HAINSWORTH, Keri R, et al. 2009. Co-occurring chronic pain and obesity in children and adolescents: The impact on health-related quality of life. In The Clinical journal of pain, 1536-5409, 2009, 25, 8, 715-721.
HINMAN, Rana S, et al. 2023. Why don't some people with knee osteoarthritis improve with exercise? A qualitative study of responders and non‐responders. Arthritis Care & Research, 2151-4658, 2023.
KING, Lauren K – MARCH, Lyn – ANANDACOOMARASAMY, Ananthila. 2013. Obesity & osteoarthritis. In The Indian journal of medical research, 0971-5916, 2013, 138, 2, 185.
KOZŁOWSKA-WOJCIECHOWSKA, M. Zasady racjonalnego żywienia. 1996. In Nowa Medycyna, 1731-2485, 1996, 3, 21, 48-59.
LENTZ, Trevor A, et al. 2019. Factors associated with persistently high-cost health care utilization for musculoskeletal pain. In PLoS ONE, 1932-6203, 2019, 14, 11, e0225125.
LIPS, Paul, et al. 2019. Current vitamin D status in European and Middle East countries and strategies to prevent vitamin D deficiency: a position statement of the European Calcified Tissue Society. In European journal of endocrinology, 1479-683X, 2019, 180, 4, 23-54.
LIU, Yanhui – CHEN, Schuchun. 2022. Interpretation and Clinical Significance of the Definition and Diagnostic Criteria for Sarcopenic Obesity: ESPEN and EASO Consensus Statement. In Chinese General Practice, 1007-9572, 2022, 0.
MCTIGUE, Kathleen, et al. 2016. Mortality and cardiac and vascular outcomes in extremely obese women. In Jama, 0098-7484, 2006, 296, 1, 79–86.
MISRA, Devyani, et al. 2019. Risk of knee osteoarthritis with obesity, sarcopenic obesity, and sarcopenia. In Arthritis & Rheumatology, 1529-0131, 2019, 71, 2, 232-237.
O'MALLEY, Grace - HUSSEY, Juliette - ROCHE Edna. 2012. A pilot study to profile the lower limb musculoskeletal health in children with obesity. In Pediatric Physical Therapy, 1538-005X, 2012, 24, 3, 292-298.
PANG, Benedict Wei Jun, et al. 2021. Coexistence of osteoporosis, sarcopenia and obesity in community-dwelling adults–The Yishun Study. In Osteoporosis and Sarcopenia, 2405-5255, 2021, 7, 1, 17-23.
PODESZWA, David A, et al. 2006. An analysis of the functional health of obese children and adolescents utilizing the PODC instrument. In Journal of Pediatric Orthopaedics, 1539-2570, 2006, 26, 1, 140-143.
REIJMAN, Max, et al. 2007. Body mass index associated with onset and progression of osteoarthritis of the knee but not of the hip: the Rotterdam Study. In Annals of the rheumatic diseases, 0003-4967, 2007, 66, 2, 158-162.
REYES, Carlen, et al. 2016. Association between overweight and obesity and risk of clinically diagnosed knee, hip, and hand osteoarthritis: a population-based cohort study. In Arthritis Rheumatol, 1529-0131, 2016, 68, 8, 1869–75.
SHULTZ, Sarah P – BYRNE, Nuala M – HILLS, Andrew P. 2014. Musculoskeletal Function and Obesity: Implications for Physical Activity. In Current obesity reports 3, 2162-4968, 2014, 355–360.
TAYLOR, Erica D, et al. 2006. Orthopedic complications of overweight in children and adolescents. Pediatrics, 1098-4275, 2006, 117, 6, 2167-2174.
TEICHTAHL, Andrew J, et al. 2015. Weight change and change in tibial cartilage volume and symptoms in obese adults. In Annals of the rheumatic diseases, 0003-4967, 2015, 74, 6, 1024-1029.
TOWNSEND, Nick – SCRIVEN, A. 2014. Public health mini-guides: obesity London: Churchill Livingston. In Elsevier, 0346-251X, 2014.
VAARA, Jani P, et al. 2012. Associations of maximal strength and muscular endurance test scores with cardiorespiratory fitness and body composition. In The Journal of Strength & Conditioning Research, 1533-4287, 2012, 26, 8, 2078-2086.