Musculoskeletal disorders are injuries or dysfunctions affecting muscles, bones, nerves, tendons, ligaments, joints, cartilages, and spinal discs. Musculoskeletal disorders include sprains, strains, tears, soreness, pain, carpal tunnel syndrome, hernias, and connective tissue injuries of the structures previously mentioned (1)(2).
According to the Global Burden of Disease (GBD) 2010 study, LBP is currently the sixth highest burden on a list of 291 conditions and is the cause of more years lived with disability (YLDs) globally than any other disease (1)(3). Several factors have been associated with WMSD such as repetitive motion, excessive force, uncooperative and/or sustained postures, prolonged sitting and standing (4)(5).
Musculoskeletal disorders (MSD ‘s) are a diverse range of medical conditions that can result in inflammatory and degenerative effects on the bones, tissues, tendons, joints, blood vessels and surrounding peripheral nerves (6)(7).
Multi-causal in nature, these can present challenges in clinical diagnoses in the absence of a specific causative factor (8) declares that less than 10% of cases have an identifiable cause or can be directly attributed to a primary event. Symptoms may appear as a result of acute pain or discomfort following an activity, adapting to an awkward posture or as a result of intense physical exertion to which the person is unaccustomed resulting in strain, sprain or other biomechanical restriction. Due to the gradual onset in most cases the individual may not attribute pain to a specific scenario(9)(10).
Association with work is not always possible to establish whether work-related or work- exacerbated due to their complex pathology (11)(12). Therefore, in Europeans countries including Malaysia the occupational injuries are the most common health problems among workers worldwide, thus musculoskeletal disorder is a common cause of morbidity, disability, and poor quality-of-life. Its burden among workers in developed countries ranges from 56–90% (4)(6)(13).
As indicated (14)(10) musculoskeletal disorders (MSDs) are the second most common cause of disability in the world, with a double burden of economic costs and healthcare needs of individuals and a major social problem due to the associated disability. In African Nations, it was postulated that the burden of LBP would be greater in lower- and middle-income countries (LMICs). A systematic review published in 2007 revealed that the prevalence of LBP in Africa was comparable to that of developing nations, and was rising (10)(15). In addition to this, workers face a variety of risk factors related to repeated manual handling and the completion of repetitive work. This includes high workload, conducting the same task frequently, the speed and intensity of work, lack of involvement and participation in the design of work arrangements, low appreciation, and weak organizational strategies (e.g., risk assessment, reporting systems, training) (16)(17).
In developing countries including East African Counties, the comparison done at the level of the global prevalence of LBP was reported by Hoy et al. (2012) was calculated from a total of 165 studies conducted in 54 countries around the globe (developed and developing countries), over a period of 29 years (18)(19). This report demonstrated that the prevalence of LBP and other parts of organism is estimated to be between 30 and 80% among the general population and has been found to increase with age(12)(20). In addition, a higher prevalence of MSD has been associated with different factors including a lower socioeconomic status and lower education levels (8)(21).
However, in Rwanda, the most common individual diagnoses were joint disease (13.3%), angular limb deformity (9.7%) and fracture mal- and non-union (7.2%). 96% of all cases required further treatment. The prevalence of MSI increased with age and was similar in men and women. There were 352 cases, giving an overall prevalence for MSI of 5.2%. (95% CI 4.5–5.9). Only 8.2% of MSI cases were severe, while the majority were moderate (43.7%) or mild (46.3%) in 2018(4)(9).
Therefore, this research challenges the general consensus that biomechanical factors are the predominant causative factor. This is contrary to the clinical position taken by the National Institute of Clinical Excellence (NICE) who prescribe to: physical activity, manual therapy, invasive procedures and surgery whilst Consultant Orthopedic Surgeon Philip Sell goes further to state that back pain prevalence, general fatigue, discomfort/pain, injury, skills and knowledge, body characteristics, socio-economic status and environment (14)(11)(22).
The current trend of MSDs in Rwanda is that each taxi parks reports annually to the porters cooperative the diverse medical conditions of the members (23)(24). There is a scarcity of literature regarding MSDs especially in Rwanda and on porters including prevalence of MSDs, personal factors that can lead to MSD and ergonomic factors which should workers be exposed to the risk for the development of MSDs. Thus, only a limited number of studies from Rwanda reported musculoskeletal disorders and work-related ergonomic risk factors led to impairment (13)(7)(25). The prevalence of MSDs increased with age and was similar in men and women (13)(26).
However, it important to have a review on MSD especially or porters in order to reduce the costly impact on productivity and to increase workers' well-being. In Rwanda several studies are done on different aspects of MSD in different domain. However, the study on the factors associated with musculoskeletal disorders among porters in taxi parks of Kigali city, Rwanda is still identified as an existing knowledge gap.