[A special type of discogenic low back pain: normal signal intensity of magnetic resonance imaging with abnormal discography].

OBJECTIVE: To report a group of special patients showing a normal signal intensity of MRI with a positive discography and discuss its pathogenesis and clinical significance. METHODS: From August 2003 to November 2008, 288 patients with chronic low back pain were treated. Of these patients, 12 showed a normal intensity signal of MRI in lumbar intervertebral discs with a positive discography. There were 7 males and 5 females aged 20 - 44 years with an average of 29.6 years. The duration of disease was 8 months to 3 years with an average of 1.8 years. Dallas CT grading method was used for assessing the degree of annular disruption. RESULTS: Of these 12 patients, 33 lumbar discs underwent discography. Twelve discs in 12 patients showed annular disruption and low back pain reproduction. Among 12 painful discs, 3 showed grade 2 annular disruption and 9 showed grade 3 annular disruption. CONCLUSION: Patients who are refractory to conservative care and have normal signal intensity in lumbar disc MRI and who are suggested as discogenic origin and might need further treatment such as minimal invasive surgery or lumbar interbody fusion should still be examined by discography.

[Natural history and prognosis of discogenic low back pain].

OBJECTIVE: To understand the natural history and prognosis of patients with discogenic low back pain so as to offer a better guide on its clinical treatment. METHODS: From December 2003 to November 2004, we consecutively hospitalized 72 patients with discogenic low back pain diagnosed by lumbar discography. These patients were randomized into two groups. One group (n = 36) received an intradiscal methylene blue (MB) injection immediately after discography while another group (n = 36) received a placebo. Both Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) were used to assess the back pain symptoms and the lumbar function respectively during a 4-year follow-up period. RESULTS: In total, 32 of 36 patients who received a placebo injection underwent a 4-year follow-up. Of these patients, 4 cases (12.5%) had their low back pain symptoms alleviated, 1 case (3.1%) slightly improved, 3 cases (9.4%) aggravated and 22 cases (68.8%) had no change in symptoms. According to VAS and ODI scores taken at different time points, these two scores gradually decreased over time; however, no statistical significances were found (VAS: F = 3.049, P > 0.05; ODI: F = 2. 272, P > 0.05). CONCLUSION: The disease course of discogenic low back pain is chronic and persistent so that its symptoms show no improvement over time.

[Diagnosis and surgical treatment of back pain originating from endplate].

OBJECTIVE: To explore the methods of diagnosis and surgical treatment for patients with back pain originating from endplate. METHODS: All patients received examinations of radiography, CT, and MR imaging. Pain level of disc was decided by discography in each patient. The principal outcome judgment were pain and disability, and the efficacy of surgical treatment was assessed by visual analog scale (VAS) for pain, and the Oswestry disability index (ODI) for functional recovery. RESULTS: All patients with a diagnosis of back pain originating from endplate according to discography were treated with anterior or posterior fusion surgery. The mean follow-up period was three years and five months (from 2 to 6 years). Among of the 21 patients, 20 (95%) reported a disappearance or marked alleviation of low back pain, and experienced a definite improvement in physical function. A statistically significant and clinically meaningful improvement on the ODI and the VAS scores were obtained in the patients with chronic low back pain originating from endplate (P = 0.0001) after treatment. CONCLUSIONS: The study suggests that the discography and fusion surgery may be very effective methods for the diagnosis and treatment of chronic back pain originating from endplate respectively.

Crossing anastomosis of nerve bundles near innervated organs to treat irreparable nerve injuries.

OBJECTIVE: To study the therapeutical effects of crossing anastomosis of nerve on the peripheral and central nerve injuries. METHODS: Twelve kinds of central and peripheral nerve disorders and their complications were treated with 11 kinds of crossing anastomosis of nerve bundles near the innervated organs. After nerve injury and repair, somatosensory evoked potentials (SEPs) and horseradish peroxidase (HRP) retrograde tracing studies were used to investigate the rabbit's nerve function and morphology. RESULTS: The ulcers of all patients healed. Sensation, voluntary movement, and joint function recovered. Four weeks after the anastomosis of distal stump of radialis superficialis nerve and median nerve, pain sensation regained and SEPs appeared. HRP retrograde tracing studies demonstrated sensory nerve ending of medial nerve formed new connection with the body of neuron. CONCLUSION: Crossing anastomosis of nerve is an effective method to treat peripheral and central nerve injuries.