What Causes Sudden Pain And Stiffness Of Legs?
The exact location of problem needs to be identified first.
Detailed Answer:
Thanks for asking on HealthcareMagic.
I have gone through the details and understand your concerns. Let me approach the problem step by step. The first step is to identify whether the problem is involving the joints or whether it is involving the muscles in between. If the problem involves the joints, the orthopedician or more importantly, a rheumatolgist would be be able to look into the problem. But if the problem involves muscular weakness, the problem could actually be either in the muscles (myopathy), neuromuscular junction, or the end-nerves or motor neurons supplying the muscles. A neurologist can evaluate your child and tell you the exact focus of the problem. You can proceed accordingly thereafter.
I would not worry about the ESR. It is not very high and is a very non-specific marker.
Feel free to ask me back in case of further queries.
Regards