Gregory D. Cramer

Zygapophyseal joint adhesions after induced hypomobility.

OBJECTIVE Adhesions (ADH) have been previously identified in many hypomobile joints, but not in the zygapophyseal (Z) joints of the spine. The objective of this study was to determine if connective tissue ADH developed in lumbar Z joints after induced intervertebral hypomobility (segmental fixation). METHODS Using an established rat model, 3 contiguous segments (L4, L5, L6) were fixed with specially engineered, surgically implanted, vertebral fixation devices. Z joints of experimental rats (17 rats, 64 Z joints) with 4, 8, 12, or 16 weeks of induced hypomobility were compared with Z joints of age-matched control rats (23 rats, 86 Z joints). Tissue was prepared for brightfield microscopy, examined, and photomicrographed. A standardized grading system identified small, medium, and large ADH and the average numbers of each per joint were calculated. RESULTS Connective tissue ADH were characterized and their location within Z joints described. Small and medium ADH were found in rats from all study groups. However, large ADH were found only in rats with 8, 12, or 16 weeks of experimentally induced intervertebral hypomobility. Significant differences among study groups were found for small (P < .003), medium (P < .000), and large (P < .000) ADH. The average number of medium and large ADH per joint increased with the length of experimentally induced hypomobility in rats with 8 and 16 weeks of induced hypomobility. CONCLUSIONS We conclude that hypomobility results in time-dependent ADH development within the Z joints. Such ADH development may have relevance to spinal manipulation, which could theoretically break up Z joint intra-articular ADHs.

Dimensions of the lumbar intervertebral foramina as determined from the sagittal plane magnetic resonance imaging scans of 95 normal subjects

OBJECTIVES This was a 2-part study. Part 1 evaluated the reliability of measurements of the intervertebral foramina (IVF) from magnetic resonance imaging (MRI) scans, and part 2 developed a morphometric database of IVF dimensions from normal living subjects. DESIGN Part 1 was a blinded reliability study using 7 observers, and part 2 developed a morphometric database using 2 teams of 3 observers, all blinded to the results of each other. SUBJECTS Ninety-five normal subjects (46 women, 49 men) were stratified by age (range 14-84 years, average 38.8 years). OUTCOME MEASURES Part 1: Interclass correlation coefficients (ICCs) were calculated for intraobserver and interobserver reliability for 3 dimensions of the lumbar IVFs. Part 2: A database was developed using the same measures. In addition, the relationships between IVF dimensions and age, height, weight, sex, and left versus right sides of subjects were evaluated. RESULTS Part 1: All ICCs were very high (> 0.94). Part 2: 8550 measurements were made, and a morphometric database of 95 subjects, stratified by age and sex, was completed. Differences in IVF size associated with age, height, weight, sex, and side were described. CONCLUSIONS Measurements taken from MRI scans of IVFs were performed reliably. The morphometric database and IVF relationships should aid clinicians and researchers in evaluating patients with suspected foraminal stenosis and help further investigate IVF pathology and treatment of such pathology.

Evaluating the relationship among cavitation, zygapophyseal joint gapping, and spinal manipulation: an exploratory case series.

OBJECTIVE This project determined the feasibility of conducting larger studies assessing the relationship between cavitation and zygapophyseal (Z) joint gapping following spinal manipulative therapy (SMT). METHODS Five healthy volunteers (average age, 25.4 years) were screened and examined against inclusion and exclusion criteria. High-signal magnetic resonance imaging (MRI) markers were fixed to T12, L3, and S1 spinous processes. Scout images were taken to verify the location of the markers. Axial images of the L4/L5 and L5/S1 levels were obtained in the neutral supine position. Following the first MRI, accelerometers were placed over the same spinous processes; and recordings were made from them during side-posture positioning and SMT. The accelerometers were removed, and each subject was scanned in side-posture. The greatest central anterior to posterior Z joint spaces (gap) were measured from the first and second MRI scans. Values obtained from the first scan were subtracted from those of the second, with a positive result indicating an increase in gapping following SMT (positive gapping difference). Gapping difference was compared between the up-side (SMT) joints vs the down-side (non-SMT) joints and between up-side cavitation vs up-side noncavitation joints. RESULTS Greater gapping was found in Z joints that received SMT (0.5 ± 0.6 mm) vs non-SMT joints (-0.2 ± 0.6 mm), and vertebral segments that cavitated gapped more than those that did not cavitate (0.8 ± 0.7 vs 0.4 ± 0.5 mm). CONCLUSIONS A future clinical study is quite feasible. Forty subjects (30 in an SMT group and 10 in a control group) would be needed for appropriate power (0.90).

Quantification of cavitation and gapping of lumbar zygapophyseal joints during spinal manipulative therapy

OBJECTIVES The purpose of this study was to use previously validated methods to quantify and relate 2 phenomena associated with chiropractic spinal manipulative therapy (SMT): (1) cavitation and (2) the simultaneous gapping (separation) of the lumbar zygapophyseal (Z) joint spaces. METHODS This was a randomized, controlled, mechanistic clinical trial with blinding. Forty healthy participants (18-30 years old) without a history of low-back pain participated. Seven accelerometers were affixed to the skin overlying the spinous processes of L1 to L5 and the S1 and S2 sacral tubercles. Two additional accelerometers were positioned 3 cm left and right lateral to the L4/L5 interspinous space. Participants were randomized into group 1, side-posture SMT (n = 30), or group 2, side-posture positioning (SPP, n = 10). Cavitations were determined by accelerometer recordings during SMT and SPP (left side = upside for both groups); gapping (gapping difference) was determined by the difference between pre- and postintervention magnetic resonance imaging scan joint space measurements. Results of mean gapping differences were compared. RESULTS Upside SMT and SPP joints gapped more than downside joints (0.69 vs -0.17 mm, P < .0001). Spinal manipulative therapy upside joints gapped more than SPP upside joints (0.75 vs 0.52 mm, P = .03). Spinal manipulative therapy upside joints gapped more in men than in women (1.01 vs 0.49 mm, P < .002). Overall, joints that cavitated gapped more than those that did not (0.56 vs 0.22 mm, P = .01). No relationship was found between the occurrence of cavitation and gapping with upside joints alone (P = .43). CONCLUSIONS Zygapophyseal joints receiving chiropractic SMT gapped more than those receiving SPP alone; Z joints of men gapped more than those of women, and cavitation indicated that a joint had gapped but not how much a joint had gapped.

A Pilot Randomized Controlled Trial of Flexion-Distraction Dosage for Chiropractic Treatment of Lumbar Spinal Stenosis

OBJECTIVE The purpose of this pilot clinical trial was to assess the feasibility of recruiting older adults with lumbar spinal stenosis (LSS) into a clinical trial that used different dosages of flexion-distraction manipulation. METHODS This randomized controlled trial used a 4-group design. Three groups consisted of chiropractic flexion-distraction manipulation applied at different dosages (8, 12, or 18 treatments). The fourth group was given 8 treatments of placebo care. Feasibility measures included recruitment goals, adherence to various treatment schedules, credibility of the placebo treatment, and rates of adverse events. The primary outcome measure was the Swiss Spinal Stenosis Questionnaire, a validated self-report of LSS symptom severity and physical function. RESULTS The recruitment and adherence goals of the study were met with a total of 60 subjects randomized (n = 15 per group) and most subjects attending at least 75% of their scheduled visits. No adverse events were reported by any of the subjects in the trial. Our placebo treatment did not appear to be credible; most subjects correctly guessed that they were receiving a placebo treatment. Between-group effect size estimates were small, indicating larger samples are needed for future studies. CONCLUSION This pilot study showed that it is feasible to recruit patients with LSS and that most subjects will adhere to a 6-week treatment schedule. The information gained from this trial will be useful to inform the design of larger trials.

Recruitment Methods and Costs for a Randomized, Placebo-Controlled Trial of Chiropractic Care for Lumbar Spinal Stenosis: A Single-Site Pilot Study

OBJECTIVE The purpose of this article is to describe the methods for recruitment in a clinical trial on chiropractic care for lumbar spinal stenosis. METHODS This randomized, placebo-controlled pilot study investigated the efficacy of different amounts of total treatment dosage over 6 weeks in 60 volunteer subjects with lumbar spinal stenosis. Subjects were recruited for this study through several media venues, focusing on successful and cost-effective strategies. Included in our efforts were radio advertising, newspaper advertising, direct mail, and various other low-cost initiatives. RESULTS Of the 1211 telephone screens, 60 responders (5.0%) were randomized into the study. The most successful recruitment method was radio advertising, generating more than 64% of the calls (776 subjects). Newspaper and magazine advertising generated approximately 9% of all calls (108 subjects), and direct mail generated less than 7% (79 subjects). The total direct cost for recruitment was

Development of a student-mentored research program between a complementary and alternative medicine university and a traditional, research-intensive university.

40 740 or

Distribution of Cavitations as Identified with Accelerometry During Lumbar Spinal Manipulation

679 per randomized patient. The costs per randomization were highest for direct mail (

Reliability of Zygapophysial Joint Space Measurements Made from Magnetic Resonance Imaging Scans of Acute Low Back Pain Subjects: Comparison of 2 Statistical Methods

995 per randomization) and lowest for newspaper/magazine advertising (

Introducing the External Link Model for Studying Spine Fixation and Misalignment: Current Procedures, Costs, and Failure Rates

558 per randomization). CONCLUSIONS Success of recruitment methods may vary based on target population and location. Planning of recruitment efforts is essential to the success of any clinical trial.