Intradiscal quantitative chemical exchange saturation transfer MRI signal correlates with discogenic pain in human patients.

Low back pain (LBP) is often a result of a degenerative process in the intervertebral disc. The precise origin of discogenic pain is diagnosed by the invasive procedure of provocative discography (PD). Previously, we developed quantitative chemical exchange saturation transfer (qCEST) magnetic resonance imaging (MRI) to detect pH as a biomarker for discogenic pain. Based on these findings we initiated a clinical study with the goal to evaluate the correlation between qCEST values and PD results in LBP patients. Twenty five volunteers with chronic low back pain were subjected to T2-weighted (T2w) and qCEST MRI scans followed by PD. A total of 72 discs were analyzed. The average qCEST signal value of painful discs was significantly higher than non-painful discs (p = 0.012). The ratio between qCEST and normalized T2w was found to be significantly higher in painful discs compared to non-painful discs (p = 0.0022). A receiver operating characteristics (ROC) analysis indicated that qCEST/T2w ratio could be used to differentiate between painful and non-painful discs with 78% sensitivity and 81% specificity. The results of the study suggest that qCEST could be used for the diagnosis of discogenic pain, in conjunction with the commonly used T2w scan.

Technical success rate of MR elastography in a population without known liver disease.

PURPOSE: MR elastography (MRE) has a low technical failure rate in patients with chronic liver disease. The failure rate in an unscreened population is unknown. The purpose of this study was to determine the technical failure rate of MRE in patients with no known liver disease. METHODS: In this prospective trial, 633 patients received 673 scans on a 1.5 T MRI using a standard gradient recalled echo MRE protocol. Four MRE images were acquired and repeated as necessary. Two investigators in consensus categorized each failure: 1. Anatomical masking failure; 2. Iron deposition; 3. No waves (connection problem); 4. Poor wave propagation; 5. Poor passive driver placement; 6. Patient breathing problems. Full exam failure was defined as no usable data in all slices. Partial failure was no usable data on at least one slice. RESULTS: 1.0% (7/673) were full failures and 7.0% (47/673) were partial failures per patient. Full failures: iron deposition-71.4% (5/7); no waves-28.6% (2/7). 4.0% (108/2733) slice failure rate: Anatomical masking failure-31.5% (34/108); Iron deposition-25.0% (27/108); No waves-13.0% (14/108); Poor wave propagation-7.4% (8/108); Poor passive driver placement-11.1% (12/108); Patient breathing problems-12.0% (13/108). CONCLUSION: The failure rate of 1% is lower than for a screened population. Iron overload was implicated in most full failures. This study demonstrates the high technical success rate of MRE in an unscreened population laying the foundation for MRE as a possible screening tool for the general public.

Thoracic costotransverse joint pain patterns: a study in normal volunteers.

BACKGROUND: Pain referral patterns of asymptomatic costotransverse joints have not been established. The objective of this study was to determine the pain referral patterns of asymptomatic costotransverse joints via provocative intra-articular injection. METHODS: Eight asymptomatic male volunteers received a combined total of 21 intra-articular costotransverse joint injections. Fluoroscopic imaging was used to identify and isolate each costotransverse joint and guide placement of a 25 gauge, 2.5 inch spinal needle into the costotransverse joint. Following contrast medium injection, the quality, intensity, and distribution of the resultant pain produced were recorded. RESULTS: Of the 21 costotransverse joint injections, 16 (76%) were classified as being intra-articular via arthrograms taken at the time of injection, and 14 of these injections produced a pain sensation distinctly different from that of needle placement. Average pain produced was 3.3/10 on a 0-10 verbal pain scale. Pain was described generally as a deep, dull ache, and pressure sensation. Pain patterns were located superficial to the injected joint, with only the right T2 injections showing referred pain 2 segments cranially and caudally. No chest wall, upper extremity or pseudovisceral pains were reported. CONCLUSION: This study provides preliminary data of the pain referral patterns of costotransverse joints. Further research is needed to compare these findings with those elicited from symptomatic subjects.

A comparison between two physical therapy treatment programs for patients with lumbar spinal stenosis: a randomized clinical trial.

STUDY DESIGN: Multicenter randomized, controlled trial. OBJECTIVE: To compare two physical therapy programs for patients with lumbar spinal stenosis. SUMMARY OF BACKGROUND DATA: Scant evidence exists regarding effectiveness of nonsurgical management programs for lumbar spinal stenosis. METHODS: Fifty-eight patients with lumbar spinal stenosis were randomized to one of two 6-week physical therapy programs. One program included manual physical therapy, body weight supported treadmill walking, and exercise (Manual Physical Therapy, Exercise, and Walking Group), while the other included lumbar flexion exercises, a treadmill walking program, and subtherapeutic ultrasound (Flexion Exercise and Walking Group). Perceived recovery was assessed with a global rating of change scale. Secondary outcomes included: Oswestry, a numerical pain rating scale, a measure of satisfaction, and a treadmill test. Testing occurred at baseline, 6 weeks, and 1 year. Perceived recovery, pain, and other healthcare resources used were collected with a long-term follow-up questionnaire. RESULTS: A greater proportion of patients in the manual physical therapy, exercise, and walking group reported recovery at 6 weeks compared with the flexion exercise and walking group (P = 0.0015), with a number needed to treat for perceived recovery of 2.6 (confidence interval, 1.8-7.8). At 1 year, 62% and 41% of the manual therapy, exercise, and walking group and the flexion exercise and walking group, respectively, still met the threshold for recovery. Improvements in disability, satisfaction, and treadmill walking tests favored the manual physical therapy, exercise, and walking group at all follow-up points. CONCLUSIONS: Patients with lumbar spinal stenosis can benefit from physical therapy. Additional gains may be realized with the inclusion of manual physical therapy interventions, exercise, and a progressive body-weight supported treadmill walking program.