Monthly Pain Update – August 2023
Loss of Cervical Lordosis Its Connection to Headaches
According to a 2015 study, 85.7% of headache patients also experience neck pain, a percentage about 50% greater than the non-headache population. Additionally, several studies have shown that treatment to address musculoskeletal issues in the neck can reduce the frequency, intensity, and duration of several types of headaches, including migraines. One of the most important aspects of the neck is the cervical spine, which serves to protect the spinal cord and support the head with its unique curved shape, also known as cervical lordosis.
At birth, the shape of the spine resembles the letter C, and around the age of three months, the cervical spine starts to become lordotic (reversed C) as the baby learns to raise its head. At around six months of age, as the infant adopts seated and standing postures, the lower back or lumbar spine also becomes lordotic. By age one, a baby’s spine includes the three normal curves: cervical lordosis, thoracic kyphosis, and lumbar lordosis.
However, a combination of mechanical overloading, structural degeneration, neck extensor muscles weakness and atrophy, and even trauma can affect the curve of the cervical spine. This can lead the head to rest forward of the sagittal plane, causing the muscles and soft tissues at the back of the neck and shoulders/upper back to work harder to keep the head upright, which can contribute to headaches.
In a March 2023 study, researchers compared headache characteristics of patients with normal cervical lordosis and patients with loss of cervical lordosis. While the research team found no differences between the groups with respect to frequency, severity, localization, lateralization, and spread, they did observe that loss of lordosis is associated with longer headache duration. The authors concluded that the loss of cervical lordosis resulted in longer lasting headaches, and this unique finding should be addressed in the headache management process when present.
As each patient is unique and each doctor of chiropractic brings their own clinical experience and training (including post-grad training) to the table, the treatment process for restoring cervical lordosis can vary from patient to patient. However, treatment will likely include a multimodal approach that includes strengthening of the cervical extensor muscles (often weak in patients with loss of cervical lordosis), cervical spinal manipulation, extension cervical traction, and at-home exercises and posture training. As demonstrated in a February 2022 case report, a 26-year-old female with a history of headaches and loss of cervical lordosis experienced a resolution of her headaches following an eight-week treatment plan to restore the cervical curve.
Consider Chiropractic Care for Post-Surgical Spine Pain
While treatment guidelines recommend exhausting conservative approaches—such as chiropractic care—before considering surgery, this doesn’t always happen. In fact, hundreds of thousands of surgeries for low back-related conditions are performed each year in the United States alone, and it’s estimated that—depending on the criteria used—between 4% and 50% of patients may continue to report ongoing low back pain and other symptoms. In the past, this condition was known as failed back surgery syndrome but has since been reframed as persistent spinal pain syndrome type-2 (PSPS-2). Can chiropractic care benefit the PSPS-2 patient?
In April 2023, researchers published a study that looked at a decade of data concerning 81,291 patients who had received chiropractic spinal manipulation and were treated at academic health centers in the United States. The data show that 10.8% of these patients had a history of at least one prior spine surgery. Further analysis revealed that these patients were more likely to be older with multiple medication prescriptions and a history of spinal injections.
A study published the previous year looked at the charts of 6,589 low back pain patients from twenty chiropractic clinics. Just over four-in-five (81%) of patients with a previous history of back surgery had undergone a laminectomy with discectomy, and fusion procedures accounted for the remainder. These patients generally received a multimodal treatment approach that included spinal manipulation (100%), drop technique (81%), passive modalities (65%), soft tissue manipulation (13%), flexion distraction (13%), and mechanical traction (13%). At the conclusion of treatment, all patients reported clinically important improvements in pain and disability, and 48% continued to report such improvements a year later. Upon further analysis, the researchers found that characteristics linked to the best long-term outcomes for PSPS-2 patients under chiropractic care include younger age, shorter history of back pain, and higher pain and/or disability levels at the onset of treatment.
The findings from this pair of studies suggest that a significant number of patients who undergo back surgery may continue to experience back pain, and many of these patients seek chiropractic care. The good news is that most (if not all) report clinically significant relief, and up to half may continue to report reduced pain and disability for a year or longer without additional care.
Of course, in a perfect world, your doctor of chiropractic would prefer you seek care for low back pain before considering surgery because, not only is chiropractic a recommended front-line treatment for low back pain, but a 2013 study found that patients who received chiropractic care first were nearly 29 times less likely to eventually have back surgery than those who initially consulted with a surgeon!
A Brief Summary of Carpal Tunnel Syndrome
Carpal tunnel syndrome (CTS) is the most common peripheral nerve entrapment neuropathy, meaning the compression of a nerve beyond the brain and spinal cord. In this case, the median nerve is compressed as it passes through the carpal tunnel of the wrist, which is comprised of eight small carpal bones that form the roof and walls of the tunnel and the transverse carpal ligament that acts as the floor of the tunnel. Let’s discuss the effect that compression of the median nerve has on an individual and how it can be managed without surgery.
The median nerve transmits motor instruction into the thumb, index, middle and thumb-side half of the ring finger, and parts of the palm. It also relays sensory information from those parts of the hand back to the brain. In addition to the median nerve, other soft tissues pass through the carpal tunnel, and if anything reduces the available space in the tunnel, it can compress or restrict the movement of the median nerve, negatively affecting its function. Initially, the patient may experience brief episodes of pain, numbness, tingling, and weakness. Over time, symptoms can become more frequent, intense, and longer lasting to the point that they transition from a minor annoyance to a real problem that interferes with normal activities.
Individuals born with a smaller carpal tunnel may be more prone to develop the condition. Likewise, hormonal conditions that may cause swelling or fluid retention can place added pressure in the carpal tunnel. But in most instances, the most common cause is inflammation caused by the repetitive work or leisure movements with insufficient rest combined with awkward wrist postures and/or excessive vibration exposure.
When a patient seeks care for CTS at a chiropractic clinic, their first step is to complete paperwork that can provide their chiropractor with information on the patient’s overall health history, as well as data specific to their hand and wrist symptoms. Based on this information, their doctor of chiropractic will conduct an examination to get a better idea as to possible pain generators. This will include a thorough look at the full course of the median nerve from the neck and through the shoulder, elbow, and forearm as compression in these areas can not only stimulate symptoms akin to CTS, but they can also increase the risk for compression at the wrist. In order to achieve a satisfactory outcome, each compression site will need to be addressed. If non-musculoskeletal causes are suspected, the doctor of chiropractic may co-manage the patient with a medical physician or specialist.
Treatment may focus on the application of manual therapies, modalities, specific exercises/stretches, work modifications, and nutritional recommendations aimed to either restore normal movement in the affected joint/s or reduce inflammation. The good news is that in cases of mild-to-moderate CTS, a conservative multimodal approach is likely to lead to a good outcome for the patient. In more severe cases, total resolution may not be possible, even if the patient elects for surgery. Hence, the common refrain among healthcare providers to opt for care early in the course of the disease and not to put off treatment until it’s unbearable.
The Biceps Tendon and Shoulder Pain
The bicep muscle could be imagined as two muscles side by side that ultimately separate into two “heads” that attach to tendons and connect into the shoulder complex. The short head of the bicep connects to the scapula and is rarely a pain generator. On the other hand, the long head of the bicep attaches to the glenoid, which is where the humerus connects to the shoulder blade, or the area we more often call the rotator cuff. If the tendon that connects the long head of the bicep to the glenoid becomes inflamed due to excessive friction or overloading of the muscle-tendon unit—more accurately described as long head of the biceps tendosynovitis or LHBT—it can be experienced as pain in the anterior (front) of the shoulder.
This tendinopathy often co-occurs with other shoulder conditions such as rotator cuff disease or subacromial impingement. As such, LHBT is typically addressed as part of a multimodal treatment approach starting with conservative care first before healthcare professionals consider more invasive options, like surgery. In a chiropractic setting, non-surgical LHBT management begins with a case history and careful examination of the shoulder and adjacent sites of the body to determine all potential causes of the patient’s pain and disability.
In-office treatment may involve both thrust and non-thrust manipulative therapy techniques applied to the shoulder joints, as well as the cervical and thoracic spinal regions. Soft tissue techniques may also be used to address issues found in the muscles surrounding the shoulder region. Treatment may also include modalities like ultrasound, electrotherapy, laser therapy, extracorporeal shockwave therapy, pulsed magnetic field, and iontophoresis.
Patients will also be advised to remain active within pain tolerances and be provided with assurance that their condition will improve. These instructions are very important because it’s natural for people with a painful condition to modify or even cease activities to avoid pain, but these practices are more likely to prolong pain and disability and lead to additional problems. In addition to diet and supplement recommendations to reduce inflammation, patients may also be asked to perform exercises at home to facilitate the treatment process. This can include resistance training and/or stretches, depending on the patient’s unique case.
As with many musculoskeletal conditions, the earlier in the course of the disease you seek treatment, the more likely you’ll receive a satisfactory outcome with conservative approaches. However, if the condition does not improve, the patient’s chiropractor may co-manage the case with a medical physician or specialist if pharmaceuticals, injections, or surgery may be required.
Does Arthritis Worsen Whiplash Outcomes?
Cervical spondylosis—also known as cervical osteoarthritis (OA)—is the most common age-related disorder of the cervical spine, which is characterized by degeneration of the intervertebral disks and facet joints as well as spur formation off the vertebral body endplates. Studies have shown that X-rays of 95% of adults over the age of 65 will show signs of cervical OA, even in the absence of neck pain or other symptoms. Because whiplash is a process that affects the cervical spine, how might pre-existing cervical OA impact whiplash recovery?
A comprehensive literature search conducted in 2021 identified nine studies that included 894 patients. An analysis of the data from these studies revealed a statistically significant association between moderate facet joint degeneration (with or without concurrent disk degeneration) and non-recovery. Past studies involving both cadavers and medial branch nerve blocks have demonstrated that degenerative changes to the facet joints can alter biomechanics in the spine and are commonly a pain source for patients experiencing spinal pain, including neck pain. In four of the studies, researchers observed a significant correlation between cervical OA and poor prognosis following whiplash injury with a higher risk than the general population for persistent whiplash associated disorders (WAD) symptoms up to two years following their whiplash event. Interestingly, the data did not show a link between isolated disk degeneration and non-recovery.
Current research suggests that nearly 50% of WAD patients will continue to experience symptoms that include neck pain, stiffness, paresthesia, dizziness, deafness, tinnitus, depression, sleep disturbance, and posttraumatic stress disorder. The 2021 literature review mentioned above suggests that cervical spondylosis may be a risk factor for chronic WAD. This is potentially troubling as studies have shown that excessive device use may result in signs of cervical OA at younger ages.
These new findings, in addition to other risk factors for chronic WAD—central sensitization, high initial pain and disability, current low back pain at time of whiplash event, history of neck pain, new onset headaches, post-injury anxiety, and cold hyperalgesia (high sensitivity to cold)—can help doctors identify patients at elevated risk for worse WAD outcomes so a more aggressive treatment plan can be adopted. Doctors of chiropractic are well equipped to manage WAD cases with a multimodal treatment approach in conjunction with allied healthcare providers, when necessary.
Is Habitual Knuckle Cracking Healthy or Harmful?
Voluntary knuckle cracking is a common habit for between 25-45% of the adult population in the United States. Some people think it’s a harmless occurrence while others say it can cause arthritis in the hands. What does the available research say on the topic?
Before the late 1930s, researchers thought that only unhealthy joints cracked. But a study published in 1938 proved that cracking can also occur in normal joints. In 1947, scientists used radiography (x-rays) to visualize the cracking of the metacarpal phalangeal joint (large knuckle in hand). A slight separation occurred when a distracting force was applied. Once it reached a certain point, a cracking sound was heard when the joint space widened suddenly. This was followed by a twenty-minute period called the "refractory phase," during which the joint gradually returned to its original resting position. Researchers described a “clear space” on the x-ray that they hypothesized to represent a vapor cavity or “bubble” arising from dissolved gas emitted from the synovial fluid.
However, a study published in 1971 refuted this finding with a conclusion that the formation of the clear space, or bubble, was not the source of joint cracking but rather, the crack was caused by the collapse of the bubble, which they felt could damage the surfaces adjacent to the bubble. Controversy continued over the years with some investigators claiming that joint cracking occurs through ligamentous recoil while others described an additional mechanism known as viscous adhesion, or tribonucleation. This is a process that occurs when two closely opposed surfaces are separated by a thin film of viscous fluid, and when rapidly distracted, viscous adhesion or tension between them releases, causing a negative pressure and creates a vapor cavity within fluid. More recently, a 2015 study using motion MRI found that joint cracking is associated with cavity inception rather than collapse of the bubble.
A 1990 study that included 300 osteoarthritis patients with functional hand impairment found no difference in arthritic symptoms between habitual knuckle crackers and non-knuckle crackers. But, the researchers did observe that the patients in the knuckle cracker group were more prone to hand swelling and weaker grip strength. A pair of 2017 studies found no difference in grip strength between knuckle crackers and non-knuckle crackers in another set of hand osteoarthritis patients, but the patients in the knuckle cracking group did exhibit increased cartilage thickness and a slight increase in range of motion in these knuckle joints. There’s even a study published in 2011 that found habitual knuckle crackers may have a slightly lower risk for osteoarthritis of the hand.
In 1998, Dr. Donald Unger wrote that he spent a half-century cracking the knuckles of his left hand but never his right. After fifty years, he reported no arthritis or other problems in either hand, despite cracking the knuckles in his left hand over 36,500 times. Ultimately, it appears that habitual knuckle cracking is probably safe. That being said, if excessive knuckle cracking stimulates symptoms, then stop and talk to your doctor of chiropractic to see if a more serious condition may be at play or if it may be time to adopt a new habit.
This information should not be substituted for medical or chiropractic advice. Any and all healthcare concerns, decisions, and actions must be done through the advice and counsel of a healthcare professional who is familiar with your updated medical history.
