This can result in frequent falls, difficulty in running, climbing stairs and rising from the floor. As the condition progresses, people can have problems with walking. Shoulder and arm weakness can lead to difficulties in raising the arms above the head, and shoulder blade winging may be present (scapular winging).
As the condition progresses, the distal muscles (hand and forearm muscles in upper limbs and ankle and calf muscles in the lower limbs) can also be involved. People may experience difficulty in doing simple tasks owing to hand weakness (for example opening bottles) and in walking because of foot weakness (foot drop) which causes them to stumble frequently.
Some people complain of muscle pain, especially in the legs. Less often, calf hypertrophy (large calves) may be present. As the condition progresses, people may develop joint contractures (tightening) in the arms (elbows) and legs (ankles). Facial and neck muscles are not usually involved. However, some people may show mild facial weakness, with difficulties in inflating their cheeks, whistling and may experience fatigue in chewing.
People with LGMD1B are at risk of heart problems. These heart problems can be mild to severe even when weakness does not have an impact on a person’s daily activities. Problems with the heart can begin at the onset of weakness and would tend to increase with time.
The heart involvement in LGMD1B usually consists of rhythm and conduction disturbances and less frequently dilated cardiomyopathy. People with heart problems can experience symptoms of breathlessness, tiredness or palpitation (funny beats). However, some people can have heart problems even when they do not show symptoms.
Less frequently, people with LGMD1B may develop respiratory muscle weakness and experience breathing difficulties with the progression of the condition. Breathing symptoms can include; poor sleep, nightmares, tiredness or headaches after waking up in the morning, lack of appetite and falling asleep during the day.
LGMD1B is quite a variable condition in terms of severity and the weakness, but usually the progression is slow to moderate and people remain on their feet and able to walk (ambulant).