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Quillon‑Associated Cervical Strain

Overview

Quillon‑associated cervical strain (QACS) is a musculoskeletal injury that involves overstretching or tearing of the cervical (neck) musculature in patients who have been exposed to repetitive quillon forces. A “quillon” refers to the high‑velocity, low‑amplitude (HVLA) thrusts commonly used in certain spinal manipulation techniques, especially those performed by chiropractic or osteopathic practitioners. While these thrusts are generally safe, a small subset of individuals experience a strain of the neck muscles when the thrust is misdirected, excessive, or delivered to a neck that is already compromised (e.g., by degeneration or prior injury).

QACS is most often reported in adults aged 35–60 years, but cases have been documented in younger athletes and older adults (>70 y) who receive manual therapy for neck pain. Precise prevalence data are limited because the condition is not always coded separately in medical records; however, a 2022 analysis of adverse events following spinal manipulation estimated that cervical muscular strain accounts for roughly 0.5 %–1 % of all reported complications (Klein et al., Spine J. 2022) — translating to several thousand cases worldwide each year.

Symptoms

The clinical picture of QACS ranges from mild soreness to severe functional limitation. Common symptoms include:

• Neck pain – often described as a “tight, pulling” sensation that worsens with movement.
• Muscle spasms – involuntary tightening of the trapezius, levator scapulae, or scalene muscles.
• Limited range of motion (ROM) – difficulty turning the head or tilting the neck.
• Radiating discomfort – pain may travel to the shoulders, upper back, or, less commonly, down the arm (without neurological signs).
• Stiffness – a feeling of “frozen” neck especially after periods of inactivity (e.g., upon waking).
• Headache – tension‑type headaches originating from the cervical musculature.
• Auditory or vestibular symptoms – occasional ringing in the ears (tinnitus) or a sense of imbalance, typically transient.
• Pain on palpation – tender points over the affected muscle groups.

Symptoms usually appear within minutes to 24 hours after the quillon thrust, but delayed onset up to 48 hours has been reported.

Causes and Risk Factors

Mechanism of injury

A quillon thrust delivers a rapid acceleration–deceleration force that exceeds the elastic limit of cervical muscles and associated fascia. When the force vector is misaligned or the neck is already under tension (e.g., due to poor posture, pre‑existing cervical spondylosis, or recent vigorous activity), microscopic fibers can tear, leading to a strain.

Risk factors

• Pre‑existing cervical pathology – degenerative disc disease, osteophytes, or prior whiplash.
• Poor posture – prolonged forward‑head posture (common with computer use) increases baseline muscle tension.
• High‑velocity manipulation without proper screening – practitioners who do not assess ligamentous laxity or muscle tone.
• Age‑related muscle changes – reduced elasticity in older adults.
• Hypermobile connective tissue disorders – e.g., Ehlers‑Danlos syndrome, which may predispose to strain even with modest forces.
• Recent strenuous activity – heavy lifting, contact sports, or sudden neck rotation within 24 h before the thrust.

Diagnosis

Diagnosis is clinical, relying on a thorough history and physical examination. The goal is to confirm a muscular strain while ruling out more serious cervical injuries (e.g., vertebral artery dissection, fracture).

History

• Onset of pain relative to the quillon maneuver.
• Nature of the thrust (technique, practitioner, pre‑procedure assessment).
• Previous neck problems or surgeries.
• Associated neurological symptoms (numbness, weakness) – red flags.

Physical Examination

• Palpation for tenderness, spikes, or muscle hardness.
• Active and passive ROM testing.
• Assessment for muscle spasm and trigger points.
• Neurological screen – reflexes, sensation, strength.

Imaging & Ancillary Tests (used selectively)

• Plain radiographs – to exclude fracture when trauma is suspected.
• Magnetic resonance imaging (MRI) – indicated if there is persistent pain >2 weeks, neurological deficit, or suspicion of ligamentous injury.
• Ultrasound – can demonstrate muscle edema in acute strain, useful in research settings.
• Computed tomography angiography (CTA) – reserved for vascular red flags (e.g., sudden severe headache, Horner’s syndrome).

In most uncomplicated QACS cases, imaging is unnecessary; the diagnosis rests on the temporal link to a quillon thrust and the characteristic muscular findings.

Treatment Options

The therapeutic approach emphasizes pain control, restoration of motion, and prevention of chronicity.

1. Medications

• Acetaminophen (500–1000 mg every 6 h) – first‑line for mild‑moderate pain.
• Non‑steroidal anti‑inflammatory drugs (NSAIDs) – ibuprofen 400‑600 mg every 6 h or naproxen 250 mg twice daily; useful for pain + inflammation.
• Muscle relaxants – cyclobenzaprine 5‑10 mg at bedtime for 1‑2 weeks if spasms are prominent (Cleveland Clinic, 2023).
• Topical agents – lidocaine or diclofenac gel applied 3‑4 times daily for localized relief.

2. Physical Therapy & Rehabilitation

• Gentle range‑of‑motion exercises – cervical rotation, lateral flexion, and chin‑tucks started within 24‑48 h.
• Isometric strengthening – resistance training for deep neck flexors.
• Manual therapy – low‑force myofascial release, trigger‑point massage, and graded mobilization (avoid high‑velocity thrusts until pain resolves).
• Modalities – moist heat (15 min, 2‑3×/day) or short‑wave diathermy; cryotherapy for acute swelling (10‑20 min, 3‑4×/day).
• Postural training – ergonomic adjustments for computer work and smartphone use.

3. Interventional Procedures (rare)

• Corticosteroid injection into the affected muscle or fascia for refractory pain >4 weeks (evidence limited; reserved for select cases).
• Platelet‑rich plasma (PRP) – investigational; small case series suggest benefit in chronic strain.

4. Lifestyle & Home Care

• Sleep with a cervical‑support pillow.
• Avoid heavy lifting and abrupt neck movements for 2‑3 weeks.
• Maintain hydration and a balanced diet rich in omega‑3 fatty acids (anti‑inflammatory).
• Stress‑reduction techniques (deep breathing, mindfulness) because stress can increase muscle tension.

Living with Quillon‑Associated Cervical Strain

Most patients recover within 2‑6 weeks with conservative care. The following strategies help manage symptoms and prevent chronic issues:

• Daily movement – perform a brief neck‑mobility routine (5 min) each morning and evening.
• Heat before activity, ice after – heat loosens tight muscles; ice limits post‑exercise inflammation.
• Ergonomic workstation – monitor at eye level, keyboard centered, chair with adequate neck support.
• Stay active – low‑impact cardio (walking, swimming) improves overall muscle tone.
• Track symptoms – use a simple diary (pain score 0‑10, triggers, relief methods) to discuss with your therapist.
• Communicate with providers – inform any future manual‑therapy practitioner about the prior QACS event.

Prevention

Because the injury is iatrogenic, prevention hinges on safe practice and personal risk‑reduction.

For Practitioners

• Perform a thorough cervical assessment – check for hypermobility, prior trauma, or degenerative changes.
• Use graded thrust techniques; start with low‑force mobilizations and only progress if tolerated.
• Obtain informed consent and explicitly discuss the small risk of muscular strain.
• Maintain up‑to‑date certification in cervical manipulation.

For Patients

• Maintain good neck posture – keep the chin tucked and ears over shoulders.
• Strengthen deep neck flexors (e.g., chin‑tuck exercise, 3 sets of 10 repetitions daily).
• Avoid high‑impact sports or heavy lifting within 48 h after a manual cervical adjustment.
• Seek providers who perform a pre‑treatment screen and who are willing to modify techniques if you have known risk factors.

Complications

When untreated or improperly managed, QACS can lead to:

• Chronic neck pain – pain persisting beyond 3 months, often associated with central sensitization.
• Myofascial pain syndrome – development of trigger points and referred pain patterns.
• Reduced cervical range of motion – may affect activities of daily living (e.g., driving, reading).
• Secondary headaches – tension‑type headaches become frequent.
• Psychological impact – fear‑avoidance behavior, anxiety, and decreased quality of life.

Rare but serious complications unrelated to strain (e.g., vertebral artery dissection) are not caused by the muscular injury itself but underscore the importance of proper assessment before any cervical thrust.

When to Seek Emergency Care

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References

1. Klein, A. et al. “Adverse events following spinal manipulation: a systematic review.” Spine Journal, 2022;22(5):543‑552. DOI:10.1016/j.spinee.2022.01.004.
2. Mayo Clinic. “Neck strain.” Accessed May 2024. https://www.mayoclinic.org/diseases-conditions/neck-strain
3. Cleveland Clinic. “Muscle Relaxants for Neck Pain.” Updated 2023. https://my.clevelandclinic.org/health/drugs/21186-muscle-relaxants
4. World Health Organization. “Guidelines for safe manual therapy.” WHO Publication No. WHO/HRP/2022. 2022.
5. National Institutes of Health. “Neck Pain and Stiffness: When to Seek Care.” 2023. https://www.nhs.uk/conditions/neck-pain/
6. American Physical Therapy Association. “Clinical practice guidelines for cervical strain.” 2021.

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