Value of a new pathological classification of lumbar intervertebral disc herniation based on transforaminal endoscopic observations

Removal of herniated disc materials based on an imaging only method may not relieve symptoms in many patients. Therefore, the aim of the present study was to develop a transforaminal endoscopic method of classifying the pathological type of lumber intervertebral disc herniation and to compare the outcomes of surgery based on the pathological type with those of conventional endoscopic disc removal. The records of patients who received endoscopic transforaminal nucleotomy with foraminoplasty for symptomatic lumbar disc herniation between 2009 and 2013 were retrospectively reviewed. Patients were then divided into two groups: Group A, which consisted of 275 patients who received conventional endoscopic transforaminal nucleotomy with foraminoplasty between 2009 and 2011 and group B, which consisted of 316 patients who received ‘targeted’ endoscopic transforaminal nucleotomy with foraminoplasty between 2011 and 2013 (based on the pathological type of disc herniation identified at surgery, including fresh, calcified and scar type based on intraoperative observations). The results showed that there were no significant differences in age, gender, body mass index, symptom duration, operated segments or previous invasive therapies between the two groups. Moreover, evaluation of visual analogue scale pain scores and Oswestry disability index scores revealed that the patients in group B had a greater improvement in symptoms than those in group A (P<0.05). In addition, an age >40 years and a longer symptom duration were associated with the calcified type, and previous invasive therapy was associated with the scar type. Therefore, specific surgical treatment based on the transforaminal endoscopic pathological type can result in better outcomes for patients with lumbar disc herniation.