Review Concludes Facet Joint Osteoarthritis Likely Caused by Whole-Joint Failure

Facet Joint Osteoarthritis

A 2012 review 1 concerning facet joint osteoarthritis (FJ OA) explicates the current understanding of the ailment and concurs with the widely-held view that OA represents a failure of the entire facet joint, rather than only the facet joint cartilage.

 

About Osteoarthritis (OA)

Spinal OA occurs in the facet or zygapophyseal joints—paired joints at the back of the vertebral column— and is closely linked to degenerative disc disease. Though FJ OA has not been as widely studied as knee OA, the most recent view that knee OA is not caused by cartilage degeneration alone but involves a systemic imbalance that inhibits the repair of joint tissues and creates whole-joint failure may also be true of spinal FJ OA.  

 

Facet Joint Osteoarthritis (FJ OA)

FJ OA is the result of a failure in the synovial facet joints, including the surrounding cartilage, ligaments, subchondral bone, synovium, capsule, and periarticular paraspinal soft tissues and muscles. Because the FJ is part of a segmented intervertebral disc, there is an association between degenerative disc disease and FJ OA, which is most often found in the lumbar region of the spine.

Typical cross-sectional imaging (radiograph, CT, and MR) of patients with FJ OA demonstrate narrowing of the space between the facet joints, subarticular bone marrow lesions (BML), erosion, and cysts, enlargement of the articular tissues, formation of osteophytes, and disc degeneration.  

 

The Spine Sections’ Interdependence

Because the facet joint is part of a three-joint motion segment (one disc, two facet joints) of the spine, it is completely distinct from the intervertebral fibrocartilaginous disc articulation. The spine is made up of interconnected motion segments, and joint alignment and load distribution throughout the spinal column are considered integral in the progression of FJ OA.

The three joints in each segment are functionally interdependent. What affects one joint will ultimately affect the others. Injuries or diseases of the disc will cause biochemical or mechanical alterations in the facet joint, and any injury to the posterior structure will affect the disc. Facet joint problems usually start with disc injuries. The three-joint complex may fail due to insult to any of its parts. Because each three-joint segment is connected to another spinal segment, injury to any one section may lead to changes in the segments above or below the injured facet joint.

The discs are usually responsible for bearing loads, and in a healthy spine, the facet joints may carry up to 33 percent of the weight. In cases where the lumbar disc space is severely narrowed, the facet joints may bear up to 70 percent of a spinal load. The muscles around the spine help to stabilize the vertebral column and provide a sense of where the spine is positioned in space. These functions may significantly decrease with age, compromising the motion of the spinal segments and contributing to FJ OA, as well as adult degenerative scoliosis and spondylolisthesis.

 

Degeneration

Degeneration of the facet joints may begin during youth and progress over many years. Early disruption of the articular cartilage, capsule, and synovium can lead to subchondral bone and bony joint margins in later years. Thinning of the articular cartilage leads to narrowing of the space between the joints, and the cartridge can develop lesions, pitting, fissures, and flaking as it slowly erodes. The joint capsule may receive decreased blood and become fibrous and inflamed. In time, the entire posterior capsule becomes fibrous and inflamed.

 

Who is at Risk?

Age appears to be a strong correlate the development of FJ OA. Though women are more prone to a diagnosis of FJ OA based upon a lumbar CT, there is no statistically significant difference between genders when it comes to developing FJ OA. Weight—or a high BMI—plays a significant role in the progression of lumbar FJ OA, but it is only slightly relevant as a determinant in the development of cervical FJ OA. African-Americans are less likely than Caucasian Americans to develop FJ OA. Heavy lifting, carrying, or pulling objects has not been studied as a possible correlate, and other occupational motions are most likely not associated with cervical FJ OA. There is a significant correlation between disc-height narrowing and the development of FJ OA in patients of any age, weight, or sex. Patients with disc-height narrowing are twice as likely than disc-height unaffected patients to develop FJ OA. Smoking and other risky habits appear to have little bearing on the development of FJ OA, but there is an apparent correlation between lumbar FJ OA and abdominal aortic calcifications.

 

Symptoms of FJ OA

FJ OA—alone, or in combination with other disc-related ailments— may cause significant neck or lower back pain (LBP), especially in adults and older patients. This pain can be caused by nociceptors in the bone or surrounding joints. Mechanical pressures on the bone, distension of the surrounding capsules, small fractures, and synovial inflammation can contribute to muscular spasms that sensitize the nerves, creating a chronic cycle of spinal pain.

Diagnosis procedures may include lumbar hyperextension, flexion-straightening, and extension-rotation to determine whether the patient’s pain increases with these exercises. Other types of pain may also indicate FJ OA.

Fat-suppressed MRI spinal sequence studies have shown BML—a common cervical spine finding— in the lumbar FJ articular processes of up to 41 percent of back pain patients. This suggests a link between back pain and FJ BMLs. Many FJ features are easily detectable using fat-suppressed MRI’s. These include FJ effusions and periarticular and ligament edema, though these observations are currently not used to grade or evaluate FJ OA in patients.  The role of heredity in the development of FJ OA has not been adequately studied.

FJ OA can contribute to narrowing of the central spinal canal, intervertebral foramina, and the lateral recess, and spinal nerve roots in these areas may be pressed. This situation may be compounded by the development of synovial cysts.

 

Conclusions

Injury to any part of a spinal motion segment may contribute to whole-joint and/or segment failure, causing neck or back pain. Any change that affects the spinal segments, particularly disc degeneration and unbalanced joint alignment or muscle weakness, may contribute to the development of FJ OA. Aging appears to increase the risk of developing FJ OA.

Real-Time MR Imaging Shows Effects of Lumbar Traction on the Spine

Lumbar Traction on the Spine

Lumbar traction – alone, or in combination with physical therapy – has been employed for decades as a therapeutic measure in treating back pain. Numerous studies have shown that the procedure stretches muscles and ligaments, increases intervertebral space, and enlarges the foramina and apophyseal joints, but the effects of traction on herniated lumbar discs and the surrounding intervertebral areas have been difficult to study in “real time” with magnetic resonance imaging (MR) because traditional traction devices contain metal, which disrupts the magnets in MR machines.

A 2012 study 1 used a nonmagnetic traction device to study 48 patients—13 men and 35 women— with lumbar disc herniation. The purpose of the study was to determine if the effects of traction on herniated disc patients could be visualized as they were occurring.

 

The Study

Subjects in the study had all been previously diagnosed with lumbar disc herniations and were treated using 30 kg of sustained traction before MR and at 10 minute intervals for a half-hour during lumbar spine imaging. The axial and sagittal images were later reviewed to check for any significant changes that occurred during the procedure. Using the lumbar vertebral column elongation and disc reduction ration as measurements, researchers were able to identify quantitative changes caused by the traction procedure.

Applicants who were pregnant or had previously undergone back surgery, had hypertension, severe osteoporosis, cardiac pacemakers, intracranial clips, lumbar instability, disc inflammation or tumors, were excluded from this study.

 

The Results

Real-time effects of continuous traction are clearly visible when using MR imaging on patients. The study subjects demonstrated significant changes in disc shape, reductions within the openings of intervertebral discs and of herniated disc volumes, as well as widening of the facet joints and separation of the discs and their connected nerve roots, post-traction. The mean lumbar vertebral column length also increased in correspondence with the amount of time a patient underwent traction. The ability to visualize the effects of traction during real-time procedures could be a helpful treatment tool.

Back or Legs?—Load Position more Important than Technique in Reducing LBP

Reducing LBP

Frequent heavy lifting can be a major contributing factor in lower back pain (LBP), but researchers disagree when it comes to the most effective lifting mechanism to reduce spinal loads and avoid injury. While the adage, “Lift from the legs, not from the back,” sounds like good advice, recent study findings 1 suggest the benefits of “squat” lifting over “stoop” lifting may have more to do with how the load is positioned than which muscles are engaged in picking it up. The results of the in vivo study indicate a need for further research on the topic, as LBP caused by heavy lifting is responsible for missed work and high disability rates—especially in the male population. Understanding the biochemical processes involved in the different lifting techniques and how to best position loads in preparation for lifting could help alleviate injuries that cause pain and represent a tremendous cost to society.

The Study

While numerous previous studies have compared stoop lifting (using the back, keeping knees straight) and squat lifting (bending the knees, keeping the back straight), with conflicting results, this study utilized a telemeterized vertebral body replacement (VBR) to acquire in vivo measurements of lumbar spinal compression and implant forces during different spinal loading scenarios, with several study subjects. The purpose of the study was to determine if the initial weight location of a load had a significant bearing upon the amount of lumbar compression and if lifting a weight from the side with one hand would result in a lighter implant force than lifting the same load from the front.

Four male patients with compression fractures of the lumbar vertebral body were informed prior to the study that they would receive modified VBRs. Three of the subjects received the VBR in the first lumbar vertebra (L1), and one of the subjects received his VBR in the third lumbar vertebra (L3). Over the course of two surgeries, their fractures were stabilized with a fixation device which, along with the fractured vertebral body and adjacent discs, was subsequently removed. The VBR devices were then implanted and bone material was used to assist in the fusion process.

The patients were instructed on the proper mechanics of both lifting techniques (stoop and squat) and were measured over the course of 17 sessions as they employed the two techniques a total of 104 times. The patients lifted a crate with two hands from a position in front of the body, and they lifted the identical crate from a lateral position, using one hand. The crate location measurements were compared over nine sessions. The data collected identified the resultant force – the sum of three measured force components—as the determinant mode acting upon the VBR during the experiments, in which stoop—and squat-lifting were performed equal or near-equal amounts of time.

Results

The results of the study suggest that lifting from the side with a single hand results in slightly less (14%) VBR force than lifting from the front, but there is no significant difference (4%) between stoop and squat lifting in the effects of spinal loading. The study’s authors point out that there was significant variance in each patient’s lifting execution, fitness level, coordination, and flexibility, and this and other differences in loading techniques might have influenced the study’s findings. Since load-lifting efficacy may be dependent on different spinal sections (lower or upper lumbar), the study’s authors point to the need for a broader and more detailed study to determine with more certainty the effects of various load-lifting techniques on the lumbar spine’s biochemical and structural forces. Nevertheless, results of the study suggest that lateral, single-handed lifting and –more significantly—reducing a weight’s distance in anterior-posterior lifting may help reduce the effects of spinal loading.

Twin Study Suggests Non-Causal Link Between LBP and Depression

Suggests Non-Causal Link Between LBP and Depression

Chronic lower back pain (LBP) is a frequently-reported disability worldwide and may contribute to anxiety and depression when it interferes with a person’s overall quality of life. While some LBP resolves within a matter of weeks or months, patients who experience long-term or chronic LBP are more likely to report accompanying psychological distress, including symptoms of depression, because of their chronic disability. Depression is ranked second behind LBP in those living with a disability, with an estimated 85 percent of depressive patients living with some form of physical pain in addition to their psychological disturbance. The disorder, characterized by a lack of enjoyment in daily living, a reduction of interest in things, and a persistent low mood, can be precipitated or accompanied by anxiety, nervousness, or worry.

A longitudinal study of identical twins 1 conducted in Spain examined the link between chronic LBP and depression and found that the apparent correlations between psychological and LBP is most likely not causative. Rather, the relationship between the two conditions may be related to a genetic or historical predisposition to certain lifestyle factors and latent neurological susceptibilities that can be triggered by the effects of those manifested tendencies.

The Study

The study sample included 1269 adult twins born between 1940 and 1966 who were not experiencing LBP symptoms or anxiety at their initial baseline reading. The female, male, and opposite twin sets filled out questionnaires over a two-year period between 2009 and 2011, and were then queried over 2,3, or 4 year-periods as to their lifestyle, health, and other demographics.  While each of the participants were asked how often they experienced LBP or if a doctor had ever diagnosed them with the condition, the question was embedded within several unrelated questions, so as not to influence their future results on a psychological level. For the purposes of this study, the term “chronic” was defined as lasting 6 months or more.

The twin sets were assessed for symptoms of anxiety or depression in follow-up questionnaires, using the Depression and Anxiety dimension of the EQ-5D, a generic quality of life instrument wherein the answers to questions about mobility, self-care, usual activities, pain/discomfort, and anxiety or depression are used to rate the level of psychological discomfort. Patients were asked to answer a question that described how they were feeling (psychologically) on a day, and their answers were dichotomized into one of two responses: “I am not anxious or depressed,” or “I am moderately/extremely anxious or depressed.”

Potential Confounding factors were also examined, including whether the subject smoked, had sleep disorders, exercised frequently or infrequently, led a sedentary lifestyle or took part in occasional sports or light physical activities, or were engaged in frequent or infrequent mild, moderate, or vigorous recreational activities. Using logistic regression models and adjusting for confounders and all variables, researchers analyzed the collected data to determine if there existed a link between chronic LBP and depression.

Results & Conclusion

Of the study’s participants, female subjects were much more likely to smoke, experience less physical activity, have sleep disturbances, and experience more chronic LBP than their male counterparts. Though chronic LBP was associated with anxiety and depression in the unadjusted total sample data, once the confounders and variants were accounted for, this relationship was less pronounced. When the data were compared with co-twin case-controls, however, there appeared no increase in the statistics related to a link between depression and chronic LBP. This may suggest that shared familial history could influence the occurrence of LBP and of depression.

The study suggests a non-causal relationship between LBP and future symptoms of anxiety or depression. Instead, a shared nature/nurture relationship may account for both LBP and the accompanying psychological discomfort. Though the study correlates statistically with previous, non-twin studies in identifying a link between LBP and depression, it refutes the causal link and instead proposes that shared familial and biological mechanisms are more likely at play when it comes to chronic LBP and psychological distress.

Study Suggests Lumbar RFN May Contribute to Disc Degeneration

RFN, Radiofrequency Neurtotomy

Lumbar medial branch radiofrequency neurotomy (RFN), a common treatment for zygapophyseal joint pain, may be therapeutically ineffective and could contribute to disc degeneration, according to a recent study, 1 which considered the therapeutic and/or potentially negative effects of the procedure on the lumbar multifidus muscle cross-sectional area (CSA), including facet joint degeneration, or intervertebral disc degeneration. The findings of the study suggest that while the procedure remains an effective low-back pain deterrent, patients undergoing RFN show little-to-no difference in multifidus cross-sectional rates of deterioration in the zygapophyseal joints and have a greater potential for progressive disc degeneration than than untreated subjects.

The Study

Retrospective data from an academic spine treatment center was collected from 27 patients who had been treated over the course of six years. The subjects in the study had completed at least one RFN lumbar medial branch procedure, had never undergone spinal surgery, and had received magnetic resonance (MR) imagery prior to and after their RFN procedure. Each patient’s gender, age, back pain duration, pre-and post-RFN imagery, and date of RFN were recorded, as well as the history of potentially contributive medical conditions affecting the lumbar spine. The mean age of the observed subjects was 55.6 years old, and 40 percent of the subjects were male.

The MR images were viewed and analyzed by a single, unblended physician investigator, and measurements of the intervertebral disc and facet joint degeneration grade were taken for all lumbar segmental levels. The Pfirrmann grading scale was used to identify and measure any noted disc degeneration. The Weishapt lumbar facet joint disease severity grading scale, which uses a rating of 0-3 to classify any noted facet joint degeneration, was used to identify and grade evidence of joint disease present in the pre-and post-RFN imagery. The data was then further classified into two groups—those affected by RFN treatment, and those whose levels appeared unaffected by treatment.

Results

Though there appeared to be a clinically insignificant trend toward CSA, the reviewed data suggested no real change in facet degeneration but a significant increase in post-RFN rates of disc degeneration in the study subjects. The authors of the study emphasize the importance of RFN in the treatment of lower back pain and demur from concluding that the risks of the procedure outweigh the benefits of treatment. However, they claim the findings suggest a need for further research to determine the efficacy and risks of RFN as it relates to multifidus morphology, segmental anatomy, and degenerative disc disease.

Study Finds Chronic Pain Patients and Their Physicians Have Different Treatment Goals

Chronic Pain Patients

Musculoskeletal pain is a chronic and debilitating condition in the United States, and recent changes in therapeutic recommendations are changing the goals of physicians in treating their patients. As opioid-reliance and addiction have become a widespread phenomenon in our country over the past 30 years, clinical guidelines have turned away from pain-treatment as a primary outcome and moved instead towards improving physical functionality and limiting the negative effects of medication on patients. While physicians have changed their patient-related goals to comply with recent recommendations that seek to limit opioid addiction, patients continue to view pain-reduction as a primary goal of treatment, followed by diagnosis of the cause of their pain.

A recent study 1 examined the agreement between patient and doctor-centered therapeutic goals, since goal-agreement is thought to be a positive indicator of the future success of therapy.

The Study

Patients and physicians in the story were chosen from two sets of primary care residents and their patients at the University of California, Davis Medical Center, in Sacramento. The researchers sought to determine the level of agreement between doctors’ and patients’ overall treatment goals, the correlation between goal-agreement and physician-reported patient difficulty, and the amount in which any lack of goal-agreement affected the patient’s sense of satisfaction with their physicians.

Baseline measures included physician and patient demographic information, including pain-related measures typically used, physical and mental health, the propensity for catastrophizing, income, and risk for opioid misuse. The physicians completed a questionnaire immediately after each patient visit rating the overall difficulty associated with patient dissatisfaction during the visit, the patients’ symptomatic burden and need for healthcare, and a rating of which goals the doctor employed in treating the patients. The goal-ratings ranged from reducing the patients’ pain intensity, improving the patients’ overall function, minimizing medicinal side-effects, decreasing the debilitating effects of pain on the patients’ lives, and diagnosing the cause of pain.

Patients were asked to complete a questionnaire immediately after their physician visits appraising their doctors’ communication skills and the amount of trust the patients placed in their doctors. They were assessed as to the length of their association with the doctors and asked to consider the goals they felt were most important in their treatment.

The Results

The study revealed a correlation between pain and lower-income subjects that was statistically significant. There also appeared to be a link between lower physical and mental health—particularly depression and anxiety— in patients suffering from chronic pain, as compared to the U.S. population. Two-thirds of the patients reported a current or prior history of substance abuse, and approximately one quarter of the patients reported being prescribed opioids and benzodiazepines at the same time.

Conclusions

Physicians are most likely responding to the changing recommendations that reduce potential opioid abuse or reliance and are instead emphasizing improved physical functionality and a reduction in medicinal risks when treating chronic pain patients. Patients, however, continue to seek symptomatic relief as their primary treatment goal, with diagnosis as their secondary goal. Though the study concluded that patients and their doctors no longer share the same primary and secondary goals, researchers found that the discrepancy between patient- and doctor-reported therapeutic goals has little bearing in overall patient-doctor satisfaction.

Study Finds Preparing Patients for Pain May Lead to Less Emotional Distress and Catastrophic Thinking

Catastrophic Thinking

Numerous studies have noted a link between catastrophizing, depression, emotional distress, and pain expectancies. A new study 1 looks at how pain expectancy affects the mental, physical, and emotional experience of pain and finds that predicting one’s own pain response may have a significant effect in the perception of actual pain.

The Study

The study involved 120 previously pain-free students between the ages of 18-32. The students were informed, prior to the study, that they would be involved in pain research—specifically, in correlating the effects of discomfort—and that the study would not physically harm them in any way. Two researchers used moveable armrests to immerse the students’ arms in the ice water at regular intervals. The students were asked to self-measure their own pain catastrophizing using the Pain Catastrophizing Scale (PCS), with questions related to the frequency of 13 feelings they experience during pain. They were also asked to measure their depression levels using the Beck Depression Inventory (BDI), which consists of 21 questions rating symptoms of depression. The students were further asked to predict the amount of pain they would experience during the immersion using a scale of 0-10. During the cold-press immersion, the subjects were asked to describe their levels of pain at 20-second intervals, using a rating scale from 0-10. The scale was posted on the wall in front of them as a visual aid.

Findings

While the findings of the study indicate that, as in previous research, there exist a correlation between catastrophizing, accelerated pain, and emotional distress, and that there is a relationship between depression and the experience of emotional distress in response to pain, researchers found little correlation between the experience of pain and depression. Instead, a more accurate predictor of emotional distress in relation to experienced pain is the measure of pain expectancy. When a subject expected less pain than experienced, he reacted to that pain with more emotional distress. Interestingly, the subjects with higher BDI scores tended to self-predict lower pain expectancies and higher levels of emotional distress in relation to the experienced pain.

Indication

Researchers theorized that the relationship between emotional distress, depression, catastrophizing, and pain is multifaceted: subjects who expect to feel more pain are prepared for the pain they experience and therefor are less likely to be emotionally distressed by it, while patients who believe they will experience less pain react with emotional distress when confronted with actual pain and are more likely to associate distress with future painful encounters. Further, subjects who rated high on the DPI were more likely to score low on the index that predicted the amount of pain they expected to experience, perhaps suggesting that those prone to depression have a defense mechanism that compels them to anticipate less pain than other subjects might expect. When their actual pain levels are higher than they expected, they react with more emotional distress than subjects scoring lower on the BDI, which, in turn, causes them to have more catastrophic thinking. In other words, these subjects experience their emotional distress due to actual pain, rather than merely imagining more pain due to a depressive nature.

The results of the experiment could mean that patients whose pain expectancy is realistically prepared prior to a procedure will experience less emotional distress in relation to physical pain and even a reduction in the amount of pain experienced. Interventions that target catastrophic thinking may lead to less pain and less emotional distress.