[1] Karolinska Inst, Dept Clin Neurosci, S-17177 Stockholm, Sweden
[2] Lowenstromska Hosp, Stockhom Spine Ctr, S-19489 Upplands Vasby, Sweden
[3] Karolinska Inst, Dept Oncol Pathol, S-17177 Stockholm, Sweden
[4] Swedish Natl Board Forens Med, S-17165 Solna, Sweden
[5] Univ Calgary, McCaig Inst Bone & Joint Hlth, Calgary, AB T2N 1N4, Canada
[6] Karolinska Inst, Dept Physiol & Pharmacol, S-17177 Stockholm, Sweden