Your physio may also need to assess you for Wikipedia reference-linkSIJ dysfuntion.You sought physio primarily b/c of your lower back pain.SIJ dysfn could throw an LLD and pain at the low back as well. This apparent LLD could be corrected by squaring both or one of the lower limb or by the method your physio adopted.Your physio has done well by determining the nature of your limb discrepancy but a probe to SIJ might be quite revealing on your way to getting solution to the pain at the low back .yelufem.