1) Nociception Pain

In this category of pain, there is no tissue damage, and therefore no inflammation. This is the type of pain one would experience if someone
stepped on your toe; one would have pain but no tissue damage or inflammation. This type of pain does not require a healthcare provider to
diagnose the cause of the pain. The cause of the pain is obvious: someone is standing on your toe.

Likewise, this type of pain does not require healthcare provider treatment. The treatment is obvious: get the person’s foot off your toe. The
patient self-treats.

With this type of pain, once the person’s foot is off your toe, you experience immediate and lasting relief. The prognosis is excellent. This is the type of pain that most patients (and insurance companies) hope they are experiencing, hoping for instant relief. Sadly, this type of pain rarely makes it into a doctor’s office because it is self-diagnosed and treated.

2) Algogenic or Inflammatory Pain

Instead of someone stepping on your toe, they smacked your toe with a hammer. Even though the hammer is no longer actually on your toe, your toe still hurts. The hammer added something to the equation: trauma, tissue damage, and inflammation. This disruption of the tissues and blood vessels by the trauma produces and releases inflammatory chemicals that are often collectively called algogenic exudates.

The inflammatory algogenic chemicals alter the thresholds of the nociceptive afferent system, increasing the pain electrical signal to the brain. Instant relief for this type of pain is not possible. The pain subsides as inflammation resolves and the nociceptive afferents system becomes sub-threshold.

Individuals suffering from this type of pain often go to healthcare providers for relief. Treatment often involves anti-inflammatory efforts
(controlled motion, drugs, omega-3s, ice, electrical modalities, low–level laser therapy, etc.) and efforts to accelerate healing (low-level laser
therapy). Depending upon the degree of tissue injury and a myriad of individual unique characteristics, response can last days, week, or months.

Importantly, for the Doctors of Osteopathy or the chiropractic profession, there is credible evidence that mechanically-based
interventions, including spinal adjusting, can disperse the accumulation of inflammatory chemicals, reducing that person’s pain. This is particularly well documented when the source of the pain is the patient’s intervertebral disc (2).

Since the intervertebral disc is avascular, only improved motion can disperse the inflammatory chemicals. Spinal adjusting improves spinal
motion, and improved spinal motion disperses the accumulation of the inflammatory chemicals. This model was profiled by Vert Mooney, MD, in his Presidential Address International Society for the Study of the Lumbar Spine (2). Dr. Mooney states:

“Mechanical events can be translated into chemical events related to pain.”

“The fluid content of the disk can be changed by mechanical activity.”

“Mechanical activity has a great deal to do with the exchange of water and oxygen concentration [in the disc].”

“Research substantiates the view that unchanging posture, as a result of constant pressure such as standing, sitting or lying, leads to an
interruption of pressure-dependent transfer of liquid. Actually, the human intervertebral disk lives because of movement.”

“In summary, what is the answer to the question of where is the pain coming from in the chronic low-back pain patient? I believe its source,
ultimately, is in the disk. Basic studies and clinical experience suggest that mechanical therapy is the most rational approach to relief of this painful condition.”

“Prolonged rest and passive physical therapy modalities no longer have a place in the treatment of the chronic problem.”

As noted with the hammer analogy, inflammatory pain subsides as the injured tissues heal. Without controversy, injured tissues heal in three
distinct steps, as follows (3, 4, 5, 6, 7, 8):

Once again, quite important to the Doctors of Osteopathy or the chiropractic profession and their patients, these phases of healing and the
concomitant pain are greatly benefited from controlled motion (9, 10, 11, 12, 13, 14, 15, 16, 17, 18). This would include adjusting (19, 20, 21).

3) Neuropathic Pain

This category of pain is pain caused from injury and damage of the nerve itself. Neuropathic pain has the potential to become chronic and
debilitating. Neuropathic pain affects approximately 3–17% of the chronic pain population in the world (22). Important for this discussion,
neuropathic pain includes compressive neuropathology. Compressive Neuropathology

Compressive neuropathology:

Compressive neuropathology

• Peripheral compressive neuropathology, also known as compressive neuropathy. An example of compressive neuropathy is carpal tunnel syndrome. The median nerve is compressed at the wrist.

• Nerve root compressive neuropathology, also known as compressive radiculopathy. Between every spinal segmental level there is a spinal nerve root.

In compressive radiculopathy, the spinal nerve root is compressed at the level of exit from the spinal column. In the neck, the spinal nerve root extends down the shoulder and into the arm(s). In the low back, the spinal root extends down the pelvis and into the leg(s).

When a spinal nerve root is compressed (radiculopathy), it generates symptoms (pain, numbness, tingling, hypersensitivity, burning, achiness, etc.) and/or functional disturbances (weakness, atrophy, etc.) in the arm(s) and/or leg(s).

Compressive radiculopathy is often a concerning clinical syndrome seen in clinical practices. This is because excessive or prolonged compression may lead to death of some of the nerve fibers resulting in permanent functional impairments. The most common cause of nerve root compression is herniation of the intervertebral disc.

Spinal manipulation, Osteopathy, or the chiropractic profession care have a long history in the management of discogenic compressive
radiculopathy. However, these patients often require longer treatment duration and more frequent visits. To understand the magnitude of the compression, doctors often make use of diagnostic imaging, such as x-rays, MRI, CT, etc.

Statistically, compressive radiculopathy is rare, being found in less than 10% of clinical practice patients (20). Sometimes, patients suffering
from compressive radiculopathy will require a surgical decompression. Doctors of Osteopathy or the chiropractic profession are trained to monitor patient progress for any symptoms or signs that might benefit from or require a surgical consultation.

Review of Selected Studies

For decades, numerous studies have shown that spinal adjusting is appropriate and usually successful in the management of compressive
radiculopathy.

In 1954, an article was published in the Instructional Course Lectures of the American Academy of Orthopedic Surgeons, titled (23):

Conservative Treatment of Intervertebral Disk Lesions

The author states:

“From what is known about the pathology of lumbar disk lesions, it would seem that the ideal form of conservative treatment would theoretically be a manipulative closed reduction of the displaced disk material.”

“Many forms of manipulation are carried out by orthopaedic surgeons and by cultists and this form of treatment will probably always be a
controversial one.”

In 1969, a study was published in the British Medical Journal, titled (24):

Reduction of Lumbar Disc Prolapse by Manipulation

The patients in this study presented with an acute onset of low back and buttock pain that did not respond to rest. Diagnostic epidurography
showed a clinically relevant small disc protrusion, along with antalgia and positive lumbar spine nerve stretch tests. These patients were then treated with rotation manipulations of the lumbar spine, accompanied with a thrust maneuver. The manipulations were repeated until abnormal symptoms and signs had disappeared. Following the manipulations there was resolution of signs, symptoms, antalgia, and reduction in the size of the protrusions. The authors state:

“Rotation manipulations apply torsion stress throughout the lumbar spine. If the posterior longitudinal ligament and the annulus fibrosus are intact, some of this torsion force would tend to exert a centripetal force, reducing prolapsed or bulging disc material.”

“The results of this study suggest that small disc protrusions were present in patients presenting with lumbago and that the protrusions were diminished in size when their symptoms had been relieved by manipulations.”

Also, in 1969, a study was published in the Australian Journal of Physiotherapy, titled (25):

Low Back Pain and Pain Resulting from Lumbar Spine Conditions: A Comparison of Treatment Results

The author compared the effectiveness of heat/massage/exercise to spinal manipulation in the treatment of 184 patients that were grouped
according to the presentation of back and leg pain. The further the sciatic pain radiated down the leg, the greater the benefit of spinal manipulation. This study was reviewed in the 1990 book, Clinical Biomechanics of the Spine, which stated (26):

“A well-designed, well executed, and well-analyzed study.”

In the group with central low back pain only, “the results were acceptable in 83% for both treatments. However, they were achieved with spinal manipulation using about one-half the number of treatments that were needed for heat, massage, and exercise.”

In the group with pain radiating into the buttock, “the results were slightly better with manipulation, and again they were achieved with about half as many treatments.”

In the groups with pain radiation to the knee and/or to the foot, “the manipulation therapy was statistically significantly better,” and in the group with pain radiating to the foot, “the manipulative therapy is significantly better.”

“This study certainly supports the efficacy of spinal manipulative therapy in comparison with heat, massage, and exercise. The results (80–95% satisfactory) are impressive in comparison with any form of therapy.”

In 1977, the third edition of Orthopaedics, Principles and Their Applications was published. This reference book includes a section
pertaining to the protruded disc with compressive radiculopathy, titled (27):

“Treatment of Intervertebral Disc Herniation with Manipulation”

“Some orthopaedic surgeons practice manipulation in an effort at repositioning the disc. This treatment is regarded as controversial and a form of quackery by many men. However, the author has attempted the maneuver in patients who did not respond to bed rest and were regarded as candidates for surgery. Occasionally, the results were dramatic.”

In 1987, a study was published in the journal Clinical Orthopedics and Related Research, titled (28):

Treatment of Lumbar Intervertebral Disc Protrusions by Manipulation

This study involved 517 patients with protruded lumbar discs with compressive radiculopathy who were treated with manipulation. Eighty-four percent of the patients achieved a successful outcome and only 9% did not respond. The authors stated:

“Manipulation of the spine can be effective treatment for lumbar disc protrusions.”

“Most protruded discs may be manipulated.”

“Gapping of the disc on bending and rotation may create a condition favorable for the possible reentry of the protruded disc into the intervertebral cavity, or the rotary manipulation may cause the protruded disc to shift away from pressing on the nerve root.”

In 1989, a study was published in the Journal of Manipulative and Physiological Therapeutics, titled (29):

Lumbar Intervertebral Disc Herniation:
Treatment by Rotational Manipulation

This was a case study of a patient with an “enormous central herniation lumbar disc” who underwent a course of side posture manipulation.
The patient improved considerably with only 2 weeks of treatment. The authors state:

“It is emphasized that manipulation has been shown to be an effective treatment for some patients with lumbar disc herniations.”

In 1993, a “Review of the Literature” was published in the Journal of Manipulative and Physiological Therapeutics, titled (30):

Side Posture Manipulation for Lumbar Intervertebral Disk Herniation

The authors state:

“The treatment of lumbar disk herniation by side posture manipulation is not new and has been advocated by both medical manipulators.”

“The treatment of lumbar intervertebral disk herniation by side posture manipulation is both safe and effective.”

In 1995, a study was published in the Journal of Manipulative and Physiological Therapeutics, titled (31):

A Series of Consecutive Cases of Low Back Pain with Radiating Leg Pain Treated

The authors retrospectively reviewed the outcomes of 59 consecutive patients complaining of low back and radiating leg pain, and were clinically diagnosed as having a lumbar spine disk herniation with compressive radiculopathy: 90% of these patients reported improvement of their complaint after manipulation. The authors state:

“Based on our results, we postulate that a course of non-operative treatment including manipulation may be effective and safe for the treatment of back and radiating leg pain.”

In 2006, a study was published in The Spine Journal, titled (32):

Manipulation in the Treatment of Acute Back Pain and Sciatica with Disc Protrusion: A Randomized Double-blind Clinical Trial of Active and Simulated Spinal Manipulations

The purpose of this study was to assess the short- and long-term effects of spinal manipulations on acute back pain and sciatica with disc
protrusion. It involved 102 patients. The manipulations or simulate manipulations were done 5 days per week by experienced doctors for up to a maximum of 20 patient visits, “using a rapid thrust technique.” Re- evaluations were done at 15, 30, 45, 90, and 180 days. The authors state:

“At the end of follow-up a significant difference was present between active and simulated manipulations in the percentage of cases becoming pain-free.”

“Patients receiving active manipulations enjoyed significantly greater relief of local and radiating acute LBP, spent fewer days with moderate-to- severe pain, and consumed fewer drugs for the control of pain.”

“No adverse events were reported.”

In 2010, a study was published in the Journal of Manipulative and Physiological Therapeutics, titled (33):

Manipulation or Microdiskectomy for Sciatica?
A Prospective Randomized Clinical Study

Forty consecutive consenting patients with lumbar disc herniation and radiculopathy who failed at least 3 months of nonoperative management including treatment with analgesics, lifestyle modification, physiotherapy, massage therapy, and/or acupuncture, were randomized to either surgical microdiskectomy or standardized spinal manipulation. The authors state:

“Sixty percent of patients with sciatica who had failed other medica management benefited from spinal manipulation to the same degree as if they underwent surgical intervention…. Patients with symptomatic lumbar disk herniation failing medical management should consider spinal manipulation followed by surgery if warranted.”

In 2014, a study was published in the Annals of Internal Medicine, titled (34):

Spinal Manipulation and Home Exercise with Advice for Subacute and Chronic Back-Related Leg Pain

This study included 192 patients who were suffering from back-related leg pain for at least 4 weeks. The authors state:

“For leg pain, spinal manipulative therapy plus home exercise and advice had a clinically important advantage over home exercise and advice (difference, 10 percentage points) at 12 weeks.”

“For patients with subacute and chronic back-related leg pain, spinal manipulative therapy in addition to home exercise and advice is a safe and effective conservative treatment approach, resulting in better short-term outcomes than home exercise and advice alone.”

Also in 2014, a study was published in the Journal of Manipulative and Physiological Therapeutics, titled (35):

Outcomes of Acute and Chronic Patients with Magnetic Resonance Imaging

–Confirmed Symptomatic Lumbar Disc Herniations

Receiving High-Velocity, Low-Amplitude, Spinal Manipulative Therapy

The purpose of this study was to document outcomes of patients with confirmed, symptomatic lumbar disc herniations and compressive radiculopathy that were treated with side posture high-velocity, low-amplitude, spinal manipulation to the level of the disc herniation. The authors state:

“The proportion of patients reporting clinically relevant improvement in this current study is surprisingly good, with nearly 70% of patients
improved as early as 2 weeks after the start of treatment. By 3 months, this figure was up to 90.5% and then stabilized at 6 months and 1 year.”

“A large percentage of acute and importantly chronic lumbar disc herniation patients treated with spinal manipulation reported clinically relevant improvement.”

“Even the chronic patients in this study, with the mean duration of their symptoms being over 450 days, reported significant improvement,
although this takes slightly longer.”

“A large percentage of acute and importantly chronic lumbar disc herniation patients treated with high-velocity, low-amplitude side posture spinal manipulative therapy reported clinically relevant ‘improvement’ with no serious adverse events.”

“Spinal Manipulative therapy is a very safe and cost-effective option for treating symptomatic lumbar disc herniation.”

In 2021, a study was published in the American Journal of Medicine titled (36):

Spinal Manipulation for Subacute and Chronic Lumbar Radiculopathy

The objective of this study was to evaluate the efficacy of spinal manipulation for the management of subacute and/or chronic lumbar
radiculopathy. Forty-four patients, with unilateral radicular low back pain lasting more than 4 weeks, were randomly allocated to a treatment group (manipulation + physiotherapy) and a control group (physiotherapy only). The authors state:

“Spinal manipulation improves the results of physiotherapy over a period of 3 months for patients with subacute or chronic lumbar radiculopathy.”

“Minimum side effects, ease of administration, and patient satisfaction are the expected benefits of manipulation.”

In 2022, a study was published in the BMJ Open, titled (37):

Association Between Spinal Manipulation and Lumbar Discectomy in Adults with Lumbar Disc Herniation and Radiculopathy

The authors assessed matched cohorts of 5,785 patients with a mean age of 37 years. They note that it is common for patients with lumbar disc herniations and compressive radiculopathy to receive care or undergo surgery to remove herniated disc material, a procedure called discectomy. Prior studies have found that patients who initiate care for low back pain have significantly reduced odds of having discectomy.

In this study, the relative odds for discectomy were significantly reduced in the compared with the cohort receiving other care over 1-year (by
69%) and 2-year follow-up (by 77%). This study shows that patients initially receiving care for lumbar disc herniation with radiculopathy have reduced odds of discectomy over 1-year and 2-year follow-up.

Conclusions

It is understood that some patients suffering from discogenic compressive radiculopathy (neuropathic pain syndrome) will require some form of decompressive spinal surgery. The studies presented here support that prior to surgery, spinal manipulation should be tried in an effort to avoid surgery. Spinal manipulation, especially by those expertly trained is safe and often very effective. Doctors are also trained to monitor patient progress for any symptoms or signs that might benefit from a surgical consultation.

This Report is a monthly publication by myself, Dan Murphy, DC. I am a 1978 graduate of Western States Chiropractic College in Portland, OR. I have managed about 10,000 whiplash-injury cases. In the past 32 years, I have taught more than 500 12-hour post graduate continuing education classes pertaining to whiplash and spinal trauma, including 21 years of coordinating a year-long certification program in spine trauma, certified through the International Chiropractic Association. Additionally, I am board certified in chiropractic orthopedics (DABCO), and I am on the faculty at Life Chiropractic College West in Hayward, CA (28 years).

The purpose is to keep you updated as to relevant academic concepts pertaining to whiplash-injured patients. The hope is that the information is useful in terms of enhanced understanding, as well as helping the personal injury attorney deal with insurance claim adjusters and adverse medical experts.

Dr. Rand McClain, D.O. sending you this Report is an Osteopathic Medical Physician, and well versed and trained in these concepts, and can be a valuable asset in personal injury cases in terms of both academics and treatment. I hope that you find this Report and the referring doctor a valuable resource.

Sincerely,

Daniel J. Murphy DC, DABCO

REFERENCES:

1. Gunn CC; The Gunn Approach to the Treatment of Chronic Pain: Intramuscular Stimulation for Myofascial Pain of Radiculopathic Origin; Churchill Livingston; 1996.
2. Mooney V; Where Is the Pain Coming From?; Spine; October 1987; Vol. 12; No. 8; pp. 754-759.
3. Oakes BW; Acute Soft Tissue Injuries; Nature and Management; Australian Family Physician; July 1981; Vol. 10; Supplement 7; pp. 3-16.
4. Roy S, Irvin R; Sports Medicine: Prevention, Evaluation, Management, and Rehabilitation; Prentice-Hall, Inc; 1983.
5. Frank C, Amiel D, Woo S, Akeson W; Normal ligament Properties and Ligament Healing; Clinical Orthopedics and Related Research; June 1985.
6. Kellett J; Acute soft tissue injuries-a review of the literature; Medicine and Science of Sports and Exercise; American College of Sports Medicine; October 1986; Vol. 18; No.5; pp. 489-500.
7. Woo S, Buckwalter J; Injury and Repair of the Musculoskeletal Soft Tissues; American Academy of Orthopaedic Surgeons; 1988.
8. Cohen IK, Diegelmann RF, Robert F, Lindbald WJ; Wound Healing, Biochemical & Clinical Aspects; WB Saunders; 1992.
9. Stearns ML; Studies on development of connective tissue in transparent chambers in rabbit’s ear; American Journal of Anatomy; Vol. 67; 1940; p. 55.
10. Cyriax, J; Orthopaedic Medicine, Diagnosis of Soft Tissue Lesions; Bailliere Tindall; Vol. 1; 1982.
11. Salter R; Continuous Passive Motion, A Biological Concept for the Healing and Regeneration of Articular Cartilage, Ligaments, and Tendons; From Origination to Research to Clinical Applications; Williams and Wilkins; 1993.
12. Buckwalter J; Effects of Early Motion on Healing of Musculoskeletal Tissues; Hand Clinics; Vol. 12; No. 1; February 1996.
13. Hildebrand K, Frank C; Scar Formation and Ligament Healing; Canadian Journal of Surgery; December 1998; Vol. 41; No. 6; pp. 425-429.
14. Kannus P; Immobilization or Early Mobilization After an Acute Soft-Tissue Injury?; The Physician And Sports Medicine; March, 2000; Vol. 26; No 3; pp. 55-63.
15. Hildebrand KA, Gallant-Behm CL, Kydd AS, Hart DA; The Basics of Soft Tissue Healing and General Factors that Influence Such Healing; Sports Medicine Arthroscopic Review September 2005; Vol. 13; No. 3; pp. 136–144.
16. Walsh W; Orthopedic Biology and Medicine; Repair and Regeneration of Ligaments, Tendons, and Joint Capsule; Orthopedic Research Laboratory; University of New South Wales, Sydney, Australia; Humana Press; 2006.
17. Schleip R; Fascia; The Tensional Network of the Human Body; The Scientific and Clinical Applications in Manual and Movement Therapy; Churchill Livingstone; 2012.
18. Hauser RE, Dolan EE, Phillips HJ, Newlin AC, Moore RE, Woldin BA; Ligament Injury and Healing: A Review of Current Clinical Diagnostics and Therapeutics; The Open Rehabilitation Journal; 2013; No. 6; pp. 1-20.
19. Haldeman S; Modern Developments in the Principles and Practice of Chiropractic; Appleton-Century-Crofts; New York; 1980.
20. Kirkaldy-Willis WH, Cassidy JD; Spinal Manipulation in the Treatment of Low back Pain; Canadian Family Physician; March 1985; Vol. 31; pp. 535-540.
21. Fishgrund JS; Neck Pain; American Academy of Orthopedic Surgeons; 2004.
22. van Hecke O, Austin SK, Khan RA, Smith BH, Torrance N; Neuropathic Pain in the General Population: A Systematic Review of Epidemiological Studies; Pain; April 2014; Vol. 155; No. 4; pp. 654–662.
23. Ramsey RH; Conservative Treatment of Intervertebral Disk Lesions; American Academy of Orthopedic Surgeons; Instructional Course Lectures; Vol. 11; 1954; pp. 118-120.
24. Mathews JA and Yates DAH; Reduction of Lumbar Disc Prolapse by Manipulation; British Medical Journal; September 20, 1969; No. 3; pp. 696-697.
25. Edwards BC; Low back pain and pain resulting from lumbar spine conditions: a comparison of treatment results; Australian Journal of Physiotherapy; September 1969; Vol. 15; No. 3; pp. 104-110.
26. White AA, Panjabi MM; Clinical Biomechanics of the Spine; Second edition; JB Lippincott Company; 1990.
27. Turek S; Orthopaedics, Principles and Their Applications; JB Lippincott Company; 1977; page 1335.
28. Kuo PP, Loh ZC; Treatment of Lumbar Intervertebral Disc Protrusions by Manipulation; Clinical Orthopedics and Related Research; February 1987; No. 215; pp. 47-55.
29. Quon JA, Cassidy JD, O’Connor SM, Kirkaldy-Willis WH; Lumbar intervertebral disc herniation: treatment by rotational manipulation; Journal of Manipulative and Physiological Therapeutics; June 1989; Vol. 12; No. 3; pp. 220-227.
30. Cassidy JD, Thiel HW, Kirkaldy-Willis WH; Side posture manipulation for lumbar intervertebral disk herniation; Journal of Manipulative and Physiological Therapeutics; February 1993; Vol. 16; No. 2; pp. 96-103.
31. Stern PJ, Côté P, Cassidy JD; A series of consecutive cases of low back pain with radiating leg pain treated by chiropractors; Journal of Manipulative and Physiological Therapeutics; Jul-Aug 1995; Vol. 18; No. 6; pp. 335-342.
32. Santilli V, Beghi E, Finucci S; Chiropractic manipulation in the treatment of acute back pain and sciatica with disc protrusion: A randomized double-blind clinical trial of active and simulated spinal manipulations; The Spine Journal; March-April 2006; Vol. 6; No. 2; pp. 131–137.
33. McMorland G, Suter E, Casha S, du Plessis SJ, Hurlbert RJ; Manipulation or Microdiskectomy for Sciatica? A Prospective Randomized Clinical Study; Journal of Manipulative and Physiological Therapeutics; October 2010; Vol. 33; No. 8; pp. 576-584.
34. Bronfort G, Hondras M, Schulz CA, Evans RL, Long CR, Grimm R; Spinal Manipulation and Home Exercise With Advice for Subacute and Chronic Back-Related Leg Pain: A Trial With Adaptive Allocation; Annals of Internal Medicine; September 16, 2014; Vol. 161; No. 6; pp. 381-391.
35. Leemann S, Peterson CK, Schmid C, Anklin B, Humphreys BK; Outcomes of Acute and Chronic Patients with Magnetic Resonance Imaging–Confirmed Symptomatic Lumbar Disc Herniations Receiving High-Velocity, Low Amplitude, Spinal Manipulative Therapy: A Prospective Observational Cohort Study with One-Year Follow-Up; Journal of Manipulative and Physiological Therapeutics; March/April 2014; Vol. 37; No. 3; pp. 155-163.
36. Ghasabmahaleh SH, Rezasoltani Z, Dadarkhah A, Hamidipanah S, Mofrad RK, Sharif Najafi S; Spinal Manipulation for Subacute and Chronic Lumbar Radiculopathy: A Randomized Controlled Trial; The American Journal of Medicine; January 2021; Vol. 134; No. 1; pp. 135−141.
37. Trager RJ, Daniels CJ, Perez JA, Casselberry RM, Dusek JA: Association Between Chiropractic Spinal Manipulation and Lumbar Discectomy in Adults with Lumbar Disc Herniation and Radiculopathy: Retrospective Cohort Study Using United States’ Data; BMJ Open; December 16, 2022; Vol. 12; No. 12; Article e068262.

“Authored by Dan Murphy, D.C..– This publication is not meant to offer treatment advice or protocols. Cited material is not necessarily the opinion of the author or publisher.”

Neuropathic Pain vs. Soft Tissue Pain

All perceptions (e.g., hot, cold, loud, bright, smelly, hard, soft, sour, sweet, pain, etc.) are cortical, meaning perceived in the brain. All pain is perceived in the brain (1).

Pain perception is brought to the brain by nerves. Structures that do not have a nerve supply (like articular hyaline cartilage,fingernail)
cannot send the pain signal to the brain. All structures that do have a nerve supply can initiate a pain signal and send it to the brain.

The pain signal is an electrical phenomenon. As an analogy, the pain “wire” for the electrical signal is the neuron.
The pain “wire” (neuron) has specific parts that are important to this discussion:

The Pain Receptor

The receptor is found at the end of the sensory neuron. This includes soft tissues (ligament, muscles, skin, fascia, intervertebral disc, etc.).
It also includes hard tissues (bone).

The receptor has the ability to take an environmental stress and convert it to an electrical signal.

Soft tissue injuries, inflammations, and/or irritations can initiate the pain electrical signal at the receptor, and the receptor will propagate the electrical signal along the axon to the brain where the signal is perceived.

The Axon

As noted above, the primary responsibility of the axon is to propagate the electrical signal from the receptor to the brain.
There is an important exception to this, which will be explained later in this publication.

The Brain

Also, as noted above, it is the brain that perceives the pain electrical signal that is delivered to it by the axon.

Soft Tissue Injury and Repair

When watching sports, like the Super Bowl, one will observe numerous injuries. The sportscasters will often tell their audience the reason why a number of a team’s top players are not in the game, detailing the injuries that the absent player is recovering from. It is rare for these injuries to be fractures, or what is referred to as hard tissue injury. The majority of these injuries are considered to be a soft tissue injury.

Soft tissues include ligaments, muscles, skin, fascia, intervertebral disc, etc. Essentially, all injuries that are not to the bone are considered
to be a soft tissue injury. Technically, an injury to the nerve itself is a soft tissue injury. However, important for this discussion, an injury to the nerve itself will not be considered to be a soft tissue injury. This discussion will consider a nerve injury to be in a separate category of
injury called neuropathic injury.

Injured soft tissues heal in three distinct phases (2, 3, 4, 5, 6, 7,
8, 9, 10, 11, 12):

• Phase 1:     the acute inflammatory phase
• Phase 2:    the repair or proliferation phase
•  Phase 3:   remodeling phase

Stages of Healing Following soft Tissue Injury

Phase 1: The Acute Inflammatory or Reaction Phase

This phase of healing lasts up to about 72 hours. It is characterized by vasodilation, immune system activation of phagocytosis by macrophages to remove debris, and the release of prostaglandins and other inflammatory molecules.

The inflammatory chemicals play a prominent role in pain production, the increase in capillary permeability, and swelling. The wound is hypoxic because the blood vessels have been disrupted, but immune system macrophages perform their phagocytosis duties anaerobically.

Phase 2: The Repair or Regeneration Phase

This phase begins at about 48 hours and continues for approximately 6 to 8 weeks. This phase is characterized by the synthesis and deposition of collagen, which literally glues the margins of the healing breach together. The collagen that is deposited in this phase is not fully oriented in the direction of tensile strength. Rather, it is laid down in an irregular, non- physiological pattern.

Phase 3: The Remodeling Phase

This phase may last up to “12 months or more” (12). The remodeling phase is mostly influenced and controlled through the use of controlled motion. This is an important clinical application for doctors who use controlled motion as a benefit of joint manipulation (specific and controlled line-of-drive motion). This point is emphasized in the following publications:

“Early mobilization, guided by the pain response, promotes a more rapid return to full activity.”

“Early mobilization, guided by the pain response, promotes a more rapid return to full functional recovery.”

“Following this acute inflammatory phase and largely guided by the pain response of the patient, early mobilization is commenced, based upon the premise that the stress of movement on repairing collagen is largely responsible for the orientation and tensile strength of the tendons and ligaments.”

“The goal of stressing repairing tissues with controlled motion is to induce adaptive response of functionally stronger connective tissues.”

“Collagen fiber growth and realignment can be stimulated by early tensile loading of muscle, tendon, and ligament.”

“The large scar tissue mass gradually remodels, likely under the influence of the mechanical environment.”

“Maturation of the scar tissue requires mechanical loading to continue the remodeling phase of healing.”

“Normal connective tissues that function in a mechanically active environment (actually most tissues) subscribe to the ‘use it or lose it’ paradigm of tissue integrity.”

“Increased loading leads to adaptation, whereas decreased loading below a threshold leads to atrophy.”

“Mechanobiology is likely important in the healing outcome in tissues such as ligaments, tendons, and related tissues. That is, depriving healing ligaments of mechanical loading likely has a detrimental impact on healing outcome.”

“For [the] collagen network to attain an almost identical construction of the original tissue, the tissue in this phase of wound healing must be confronted with its normal physiological stress.”

“An important task for the therapist is to apply gradually increasing levels of force without causing pain, in order to promote the healing and regeneration processes and in this way restore mobility and stability.”

Most healed soft tissue injuries are asymptomatic. However, it is universally accepted that the healed tissue is weaker than the pre-injured
tissue. Consequently, acute flare-ups of pain or exacerbations of pain

and/or spasm often occur as a consequence of increased use or stress of the once injured but now healed tissues. Good early treatment improves the quality and timing of soft tissue injury. Best early treatment appears to include ice and early controlled motion. This would include soft-tissue, Osteopathic or chiropractic care involving adjusting of the injured joints.

Problem Solving

A common and legitimate question is “Why do some soft tissue injuries take a prolonged period of time to heal?” It is a reality: some patients do not recover as expected and/or take a longer period of time to become maximumly improved. This question is asked by all parties involved: the patient, doctors, insurance companies, claims adjusters, health plan administrators, lawyers, courts, family and friends, etc. The answer may b right in front of all involved. It has been described in the scientific literature for decades:

Neuropathic Pain Syndrome

The prior discussion pertained to soft tissue injuries that cause inflammations and/or irritations to the nerve receptors. These nerve
receptors reside within those tissues. As mentioned above, technically, neuropathic pain is a soft tissue injury. But in contrast to other soft
tissue injuries, the consequences and prognosis for neuropathic injury are far more difficult and less optimistic.

Simply stated, neuropathic pain is pain caused from injury, damage, or dysfunction of the nerve itself. Neuropathic pain is distinct from the pain caused by soft tissue injury. Neuropathic pain tends to become chronic and debilitating. “Neuropathic pain affects approximately 3–17% of the chronic pain population in the world” (13).

There are several Clinical Questionnaires to help establish the presence and clinical outcomes for neuropathic pain. An example of a popular
one, the DN-4, is included on page 10 of this publication.

Most musculoskeletal practitioners are unfamiliar with the concept of neuropathic pain. Yet, a search of the U.S. National Library of Medicine, using the PUBMED search engine and the words “neuropathic pain,” identifies 56,609 citations (as of February 6, 2024). The oldest of these publications appeared in the 1930s. In 2015, the International Association for the Study of Pain (IASP) declared that year to be the “global year against neuropathic pain” (14).

Typical neuropathic pain categories include:

• Lumbosacral radiculopathy
•  Piriformis sciatica
•  Carpal tunnel syndrome
•  Cervical radiculopathy
•  Neurogenic thoracic outlet syndrome
•  Chemotherapy-induced peripheral neuropathy
•  Spinal cord injury
•  Diabetic polyneuropathy
•  Post stroke pain
•  Chronic inflammatory demyelinating polyneuropathy
•  Entrapment neuropathy
•  Trigeminal neuralgia

Several of these are rarely or never seen in clinical practice (chemotherapy-induced peripheral neuropathy, spinal cord injury, diabetic
polyneuropathy, post stroke pain, demyelinating polyneuropathy).

In contrast, some of these are quite common in clinical practice and often successfully resolved or acceptably improved with osteopathic care,
including spinal adjusting (lumbosacral radiculopathy, piriformis sciatica, cervical radiculopathy, neurogenic thoracic outlet syndrome, carpal tunnel syndrome, entrapment neuropathy, trigeminal neuralgia). The radiculopathy neuropathic pain syndromes are particularly relevant to the osteopathic or chiropractic community because the nerve roots exit between the spinal vertebrae. Disc pathology, facet injury, uncinate joint injury, and spinal arthrosis and/or spondylosis all have the ability to injure, inflame, and/or irritate the adjacent nerve root axions.

A subjective hallmark of neuropathic pain has the patient complaining of multiple characteristics. These might include burning, painful cold,
electric shocks, tingling, pins and needles, numbness, itching, etc. No two patients are exactly alike. Each patient will present uniquely different.

The clinical assessment of neuropathic pain syndrome is not a simple task. Credible studies on the topic of neuropathic pain syndrome often use similar but often somewhat different questionnaires to determine the presence of neuropathic pain syndrome (15, 16). A representative example of a commonly used questionnaire is attached at the end of this publication.

In 1958, the Journal of the American Medical Association published a study titled (17):

Whiplash Injuries:
Neurophysiological Basis for Pain
and Methods Used for Rehabilitation

The author, Beverly Hills neurosurgeon Emil Seletz, MD, states:

“The person’s body (in the car that is struck) continues to move forward, while the head, being hinged at the neck, snaps backwards. The average head weighs about 8 lbs., and the cervical vertebrae are very delicate; the force that is pushing the head backwards is even greater than believed, since the base of the neck acts as a fulcrum and the leverage is applied near the top of the head.”

“Therefore, the head snaps back with the equivalent of several tons of force—without any support, since ‘the muscular control of the neck is caught off guard.’”

“The end-result, with the neck in acute hyperextension, is a momentary posterior subluxation of the various joints with fleeting narrowing of the foramina, so that the nerve root is caught in a pinchers between the superior and inferior facets.”

This discussion, “the nerve root is caught in a pinchers between the superior and inferior facets,” presents a plausible argument for the
etiology of neuropathic pain from whiplash mechanism injuries.

A recent publication (2022) in the journal Pain quantified the incidence of neuropathic pain following whiplash collisions in a study titled (18):

Nerve Pathology and Neuropathic Pain After Whiplash Injury: A Systematic Review and Meta-Analysis

This study is quite large. It reviewed 54 studies reporting on 390,644 patients and 918 controls.

The authors note that about 50% of patients suffering from whiplash injuries will suffer from chronic pain. They note that an explanation for
this high rate of chronicity is that the patients are suffering not from soft-tissue injury alone, but rather from neuropathic pain syndrome.

The authors note that the prevalence of neuropathic pain in these whiplash-injured subjects was 34% to 75%. They state:

“There is no clear understanding of the mechanisms causing persistent pain in patients with whiplash associated disorder (WAD).”

“There is increasing evidence of nerve involvement and neuropathic pain in patients with chronic WAD.”

“Our systematic review including 54 studies in 390,644 patients suggests that after whiplash injury, a subset of people demonstrate signs of peripheral nerve injury and/or neuropathic pain.”

“Neuropathic pain is reported by a significant group of patients with WAD.”

“Our data suggest that nerve pathology and signs of neuropathic pain are present in a subset of patients after whiplash injury.”

The DN-4 Questionnaire Estimates the Probability of Neuropathic Pain

This questionnaire has been well validated in a number of studies and is considered to be one of the most suitable neuropathic pain screening tools for clinical use:

7 symptom items are scored by interviewing the patient.

3 items are scored by means of clinical examination.

The scores are added and a score of 4 or more out of 10 is suggestive of neuropathic pain. YES = 1 Point; NO = 0 Points; Patient’s Score_______

Interviewing the Patient

QUESTION 1: Does the pain have one or more of the following characteristics?

Burning   ……………………………………………………………       YES      NO
Painful Cold……………………………………………………….        YES      NO
Electric shocks……………………………………………………        YES      NO

QUESTION 2: Is the pain associated with one or more of the following symptoms in the same area?

Tingling……………………………………………………………         YES      NO
Pins and needles…………………………………………………       YES      NO
Numbness…………………………………………………………        YES      NO
Itching……………………………………………………………..         YES      NO

Examination of the Patient

QUESTION 3: Is the pain located in an area where the physical examination may reveal one or more of the following characteristics?

Hypoesthesia to touch………………………………………….      YES     NO

Hypoesthesia to pinprick………………………………………      YES    NO

QUESTION 4: In the painful area, can the pain be caused or increased by?

Brushing……………………………………………………………..      YES    NO

Future Directions and Concepts

Cytokines are protein molecules that are produced by immune system cells. Cytokines can be pro-inflammatory or anti-inflammatory.

Interleukins are a category of cytokines. Like cytokines, interleukins can be either be pro-inflammatory or anti-inflammatory. Interleukins are abbreviated “IL.”

IL-27 and IL-10 are both anti-inflammatory cytokines. An important article pertaining to neuropathic pain was published in the journal
Frontiers in Immunology in 2020, titled (19):

IL-27 Counteracts Neuropathic Pain Development

Through Induction of IL-10

These authors propose that, ideally, following axonal nerve injury, the immune system cells will increase production of anti-inflammatory
cytokine IL-27. In turn, IL-27 will induce an increase in the anti- nociceptive cytokine IL-10, which inhibits neuropathic pain development
following injury. The authors state:

“These results provided evidence that IL-27 is a cytokine produced after peripheral nerve injury that counteracts neuropathic pain development through induction of the antinociceptive cytokine IL-10.”

The authors conclude that interventions that increase IL-27 and IL-10 “could emerge as possible therapeutic approaches for the prevention of neuropathic pain development after peripheral nerve injury.”

This science and perspective has a lot of relevance for Doctors of Osteopathy or the chiropractic profession and for their patients suffering
from neuropathic pain. In 2016, the World Federation of Chiropractic award winning paper was published in the Journal of Manipulative and Physiological Therapeutics, titled (20):

Attenuation Effect of Spinal Manipulation on Neuropathic and Postoperative Pain Through Activating Endogenous Anti-Inflammatory Cytokine Interleukin-10 in Rat Spinal Cord

Using animal models, these authors showed that repetitive spinal manipulative therapy “significantly reduced simulated neuropathic and
postoperative pain, inhibited or reversed the neurochemical alterations, and increased the anti-inflammatory IL-10 in the spinal cord.” They concluded:

“These findings show that spinal manipulation may activate the endogenous anti-inflammatory cytokine IL-10 in the spinal cord and thus has the potential to alleviate neuropathic and postoperative pain.”

•••••

The benefits of osteopathic or chiropractic care, including spinal adjusting, are unquestioned in the management of neuropathic pain syndromes, especially for spinal radiculopathy syndromes. Perhaps, this elevation of IL-10 following spinal adjusting is a plausible explanation.

•••••

      This Report is a monthly publication by myself, Dan Murphy, DC. I am a 1978 graduate of Western States Chiropractic College in Portland, OR. I have managed about 10,000 whiplash-injury cases. In the past 32 years, I have taught more than 500 12-hour post graduate continuing education classes pertaining to whiplash and spinal trauma, including 21 years of coordinating a year-long certification program in spine trauma, certified through the International Chiropractic Association. Additionally, I am board certified in chiropractic orthopedics (DABCO), and I am on the faculty at Life Chiropractic College West in Hayward, CA (28 years).

The purpose is to keep you updated as to relevant academic concepts pertaining to whiplash-injured patients. The hope is that the information is useful in terms of enhanced understanding, as well as helping the personal injury attorney deal with insurance claim adjusters and adverse medical experts.

Dr. Rand McClain, D.O. sending you this Report is an Osteopathic Medical Physician, and well versed and trained in these concepts, and can be a valuable asset in personal injury cases in terms of both academics and treatment. I hope that you find this Report and the referring doctor a valuable resource.

Sincerely,
Daniel J. Murphy DC, DABCO

REFERENCES

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11) Schleip R; Fascia: The Tensional Network of the Human Body; The Scientific and Clinical Applications in Manual and Movement Therapy; Churchill Livingstone; 2012.

12) Hauser RA, Dolan EE, Phillips HJ, Newlin AC, Moore RE, Woldin BA; Ligament Injury and Healing: A Review of Current Clinical Diagnostics and Therapeutics; The Open Rehabilitation Journal; 2013; No. 6; pp. 1- 20.

13) van Hecke O, Austin SK, Khan RA, Smith BH, Torrance N; Neuropathic Pain in the General Population: A Systematic Review of Epidemiological Studies; Pain; April 2014; Vol. 155; No. 4; pp. 654–662

14) IASP; Global year against neuropathic pain. 2015; Available at: http://www.iasp-pain.org/GlobalYear/NeuropathicPain? avItemNumber5580.

15) Finnerup NB, Haroutounian S, Kamerman P, Baron R, Bennett DLH, Bouhassira D, Cruccu G, Freeman R, Hansson P, Nurmikko T, Raja SN, Rice ASC, Serra J, Smith BH, Treede RD, Jensen TS; Neuropathic Pain: An Updated Grading System for Research and Clinical Practice; Pain August 2016; Vol. 157; No. 8; pp. 1599–1606.

16) Madani SP, Abdolmaleki K, Ahadi T, Mansoori K, Raissi GR; Neuropathic Pain Symptom Inventory (NPSI) Questionnaire-Persian Version Can Differentiate Neuropathic from Non-Neuropathic Pain; Pain Management Nursing; February 2023; Vol. 24; No. 1; pp. 96-101.

17) Seletz E; Whiplash Injuries: Neurophysiological Basis for Pain and Methods Used for Rehabilitation; Journal of the American Medical
Association; November 29, 1958; Vol. 168; No. 13; pp. 1750-1755.

18) Fundaun J, Kolski M, Baskozos G, Dilley A, Sterling M, Schmid AB; Nerve Pathology and Neuropathic Pain After Whiplash Injury: A
Systematic Review and Meta-Analysis; Pain; July 1, 2022; Vol. 163; No. 7; pp. e789-e811

19) Fonseca MM, Davoli-Ferreira M, Santa-Cecília F, Guimarães RM, Oliveira FFB, Kusuda R, Ferreira DW, Alves-Filho JC, Cunha FQ, Cunha TM; IL-27  Counteracts Neuropathic Pain Development Through Induction of IL-10;Frontiers in Immunology; January 28, 2020; Vol. 10; Article 3059.

20) Song XJ, Huang ZJ, Song WB, Song XS, Fuhr AF, Rosner AL, Ndtan H, Rupert RL; Attenuation Effect of Spinal Manipulation on Neuropathic and Postoperative Pain Through Activating Endogenous Anti-Inflammatory Cytokine Interleukin-10 in Rat Spinal Cord; Journal of Manipulative and Physiological Therapeutics; January 2016; Vol. 39; No. 1; pp. 42- 53.

“Authored by Dan Murphy, D.C..– This publication is not meant to offer treatment advice or protocols. Cited material is not necessarily the
opinion of the author or publisher.”