Muscle dysfunction and exercise limitation in adolescent idiopathic scoliosis

Abstract

Adolescent idiopathic scoliosis (AIS) can lead to ventilatory restriction, respiratory muscle weakness and exercise limitation. However, both the causes and the extent of muscle dysfunction remain unclear. The aim of our study is to describe muscle weakness and its relationship to lung function and tolerance to exercise in AIS patients.Lung and muscle function, together with exercise capacity, were assessed in 60 patients with pronounced spinal deformity (.40u) and in 25 healthy volunteers.Patients with AIS had only mild to moderate abnormal ventilatory patterns, the most frequent of which were restrictive abnormalities. The function of respiratory and limb muscles and exercise capacity were below normal limits in AIS patients, and were significantly lower than in controls. Exercise capacity was found to correlate with the function of inspiratory, expiratory, upper limb and lower limb muscles which, in addition, were reciprocally interrelated. Multivariate analysis showed that lower limb muscle function is the main contributor to exercise intolerance. There appeared to be no connection between spinal deformity and lung function, muscle function or exercise capacity.We conclude that AIS patients show generalised muscle dysfunction which contributes to the reduction in their exercise capacity, even in the absence of severe ventilatory impairment.

Thoracic changes and exercise capacity in patients with adolescent idiopathic scoliosis

“…In our study, we observed that AIS patients had a decrease in VO2, VO2kg, VE and VT when compared to the control group, as observed in previous studies that also used an incremental exercise protocol [11,12,20,22]. The peak of oxygen consumption is an important indicator of an individual's exercise capacity [23].…”

“…As well, changes in the chest wall and spine are related to poorer performance during exercise. Other studies have compared the exercise capacity of AIS patients and non-affected individuals, however, they used the six-minute walk test [5] or cycle ergometer test [11,12,20]. Few studies used the ISWT to assess aerobic capacity in this population [21], but they did not assess the influence of the thoracic deformity on exercise variables.…”

“…Pulmonary dysfunction is not the only limitation in exercise in patients with scoliosis. The physical deconditioning, the reduction of muscle mass and the compensatory postures adopted are also consequences of the physical activity reduction [1,11,12].…”

Skeletal Muscle Dysfunction: From Chronic Respiratory Disease to Critically Ill Patients

“…Furthermore, compared to healthy age-matched controls, a significant decrease in respiratory and limb muscle function was also observed in patients with adolescent idiopathic scoliosis that was associated with poorer exercise capacity, regardless of lung function 76 . Indeed, patients with adolescent idiopathic scoliosis exhibited significant alterations in body composition 77,78 .…”

Effects of corrective, therapeutic exercise techniques on adolescent idiopathic scoliosis. A systematic review

“…6 Studies on AIS prevalence have demonstrated that between 27% and 59% of patients suffer pain. 5,7 In addition, it may be associated with other conditions, such as restricted ventilation, respiratory muscle weakness, reduced quality of life, 8 and even psychological problems. 9 At present, according to the 2016 AIS consensus, 1 follow-up and management include observation, bracing or surgery.…”