Can nerve entrapment cause weight loss, muscle wasting and muscle weakness.

No and Yes. Motor nerve entrapment can definitely cause muscle wasting & weakness - but only of a particular muscle or muscle group innervated by that nerve. It's unlikely to cause weight loss except if you lose a large amount of muscle mass.If generalized weight loss &/or generalized muscle weakness is occurring, you need a proper medical evaluation to determine cause; it's unlikely to be nerve entrapment.
Yes. Whichever part of the body is suffering the nerve entrapment, can go for muscle wasting and weakness ,if nerves are trapped by bands, scars .Pl get evaluated by an orthopedician/neurologist /PCP, get nerve condn studies and electromyogram to confirm the entrapment. But if the muscle weakness and wasting occur in different parts of the body, cause is not local but systemic ,eg MS,motor neuron disea.