The location of low back pain can differ as a result of the underlying cause or the severity of symptoms. According to a 2016 study published in Pain Practice, the severity of low back pain is higher when pain is radiating all the way down the leg (Hüllemann et al., 2016). An interesting finding is surgery and medication intake is more frequent for these patients.
The findings associated with four pain radiation patterns as identified by Hüllemann and colleagues are reviewed here and acknowledged as patterns worth tracking.
Radiation patterns in low back pain
A main finding for the 2016 study is patients with low back pain can display four different pain radiation patterns. Well localized pain in the lumbar region is one. The others are pain radiating to (1) the thigh, (2) between the knee and ankle, and (3) the feet. Diagnoses in some of these pain radiation patterns include sciatica, unspecified low back pain and radiculopathy. However the diagnoses, of which there were many, is only a part of the picture. The pain drawings together with the questionnaires revealed so much more.
In addition to the pain drawings several other factors were assessed. Assessing pain intensity, sleep disturbance, depression, disability and utilization of the health services gave more clues. Worse pain conditions associated with pain radiating into both legs particularly at the level of the thigh. While, low back pain patients with pain radiating beyond the knee or into the feet showed evidence of neuropathic pain.
Pain extending down the leg is a crude description
The authors suggest that patients with pain extending to the feet may be due to a L5 or S1 root compression. In addition, patients with localized low back pain (axial pain) show an increase in neuropathic pain components. This increase was measured 3 – 6 months later. This study is the first to identify what may be critical transitions contributing to the severity of low back pain.
Considering the study findings, pain extending down the leg is a crude description. Instead encourage patients to precisely report the location of the radiating pain. Recording whether pain is present on both legs and assessing pain qualities is also insightful. Moreover tracking how pain is changing brings us a step closer to revealing whether a patient is improving.
Philipp Hüllemann MD, Thomas Keller DSc, Maria Kabelitz Dip, Rainer Freynhagen MD, Thomas Tölle MD, and Ralf Baron MD., (2016) Pain drawings improve subgrouping of low back pain patients. Pain Practice.