Here’s an English version of the article on “Effective Physical Therapy Methods for Patients with Cervical Disc (Neck Disc) — Principles and Evidence for Traction, Electrical, and Heat Therapies”.
I’ve preserved the structure (introduction, numbered sections, conclusion), and cited up‑to‑date scientific sources (without direct links). Let me know if you’d like further adjustments!

1. Introduction: When Your Neck Feels Heavy and Painful

When a patient tells me, “My neck feels stiff and heavy, especially in the morning, and turning it hurts,” I sense an alarm. Neck discomfort is so common in daily life that many shrug it off as stress or muscle tension. Yet sometimes the culprit is deeper: a cervical disc problem (neck disc) that presses on nerves, causing pain, numbness, or tingling. In such cases, physical therapy plays a key role in non‑surgical management. But “physical therapy” is a broad term — which modalities work best for cervical disc issues? In this article, we focus on three widely used methods — traction therapy, electrical stimulation therapy, and heat therapy — and explain their mechanisms, practical use, and evidence. Through this, patients and clinicians alike can better understand which approach fits which situation.

2. Pathophysiological Background: Why Physical Therapy Matters

A cervical disc problem occurs when one of the intervertebral discs in the neck (cervical spine) bulges, protrudes, or herniates and impinges on adjacent neural structures (nerve roots or spinal cord). This compression can provoke pain, numbness, weakness, or reflex changes in the arms or hands.

Physical therapy does not reverse the disc pathology itself, but it helps by relieving pressure on the nerve, reducing inflammation, relaxing muscle tension, and improving local circulation and tissue health. In other words, physical therapy aims to create a more favorable environment around the spine so symptoms are alleviated and further damage is minimized.

Given this background, each modality — traction, electrical stimulation, and heat — has its theoretical role. Let’s explore each in turn.

3. Traction Therapy

3.1 Mechanism of Traction

Traction therapy involves applying a longitudinal pull (a distraction force) to the cervical spine, aimed at gently separating adjacent vertebrae. The goals include:

• Increasing the intervertebral space and foraminal opening, thus reducing compression on nerve roots

• Reducing mechanical stress and tension in ligaments and soft tissues

• Promoting relaxation of muscle tone

• Improving circulation to adjacent tissues

In sum, the idea is that a mild, controlled stretching of the neck can relieve nerve compression and reduce symptoms.

The theoretical basis is well documented in review sources: traction may widen the intervertebral foramina and indirectly reduce nerve root impingement. (Source: Cervical Traction – StatPearls)
Source: Cervical Traction – StatPearls

3.2 Application Methods of Traction

Traction can be delivered in multiple forms. Key parameters include:

• Continuous vs. intermittent traction: Continuous traction applies a steady pull; intermittent alternates periods of pull and rest.

• Position: Many studies contrast supine (lying down) position vs seated position. Some evidence suggests that supine traction yields better clinical effect, possibly because muscles relax more fully in that posture. (Source: A randomized controlled trial comparing sitting vs supine cervical traction)
  Source: A randomized controlled trial of intermittent cervical traction in sitting vs supine position

• Force magnitude, angle of pull, duration, and frequency must all be calibrated.

• Home traction vs clinical traction units: Over‑door pulley systems, motorized clinic devices, or simpler home kits are used depending on context.

The effectiveness depends heavily on these parameter choices and patient selection.

3.3 Clinical Evidence and Limitations

Multiple clinical trials and meta‑analyses have assessed traction’s value, especially for cervical radiculopathy (nerve root symptoms originating from the neck).

• A meta‑analysis of seven trials (589 patients) found that adding traction to other treatments achieved a small but statistically significant reduction in pain intensity (mean difference ≈ –5.93 on a numeric scale) compared to controls. Yet the authors judged the quality of evidence as low, and the effect sizes might lack clinical importance. (Source: Traction Therapy for Cervical Radicular Syndrome meta‑analysis)
  Source: Traction Therapy for Cervical Radicular Syndrome meta‑analysis

• A retrospective study of home cervical traction (3–5 minutes, twice daily) reported symptomatic improvement in 81% of mild-to-moderate cases, though retrospective design limits strength. (Source: Efficacy of home cervical traction therapy)
  Source: Efficacy of home cervical traction therapy

• Some systematic reviews indicate that spinal manipulation (manual therapy) may outpace traction in short‑term outcomes (pain, disability) in cervical radiculopathy cases. (Source: Systematic Review comparing manipulation vs cervical traction)
  Source: Systematic Review and Meta‑Analysis of the Evaluation of the ...

• Recent studies also show that even a single session of cervical traction can temporarily reduce muscle stiffness in the upper trapezius, which may contribute to subjective relief. (Source: The effect of acute cervical traction on neck muscle stiffness)
  Source: The effect of acute cervical traction on neck muscle stiffness

Overall, traction often provides short-term symptomatic relief, particularly when applied appropriately. But evidence for long-term structural improvement or sustained symptom remission is lacking. (Source: StatPearls review)
Source: Cervical Traction – StatPearls

Thus traction should be regarded as a component of a multimodal plan — not a stand-alone cure.

4. Electrical Stimulation Therapy

4.1 Mechanism: How Electrical Stimulation Works

Electrical stimulation (electrotherapy) involves passing controlled currents through tissues. Its key effects include:

• Modulating pain signals (gate control, inhibitory pathways)

• Stimulating proprioceptive feedback

• Reducing hyperalgesia (sensitization)

• Promoting local circulation

• Inducing muscle contraction (in the case of EMS) for muscle re-education

Typical modalities in cervical disc management include TENS (transcutaneous electrical nerve stimulation), EMS (electrical muscle stimulation), and medium-frequency or interferential currents.

4.2 Practical Application and Parameters

• TENS: Electrodes placed over or near painful regions deliver low-voltage currents to modulate pain perception.

• EMS / NMES: Stronger currents evoke muscle contraction, assisting in strengthening or retraining weak musculature.

• Frequency, pulse width, intensity, and duration must be carefully selected based on patient tolerance and therapeutic goals.

4.3 Clinical Evidence of Electrical Therapy

Evidence is somewhat mixed but indicates modest support for electrical modalities as adjunctive tools.

• A comprehensive review on neck pain concluded that TENS may relieve pain better than placebo, though it did not outperform exercise or infrared modalities in many comparisons. (Source: Electrotherapy for neck pain review)
  Source: Electrotherapy for neck pain – PMC

• A 2024 study of electrotherapy’s short-term effects reported improved cervical proprioception (sense of neck position) and reduced pain when TENS was applied. (Source: Effects of Electrotherapy on Pain, Anxiety, Mobility)
  Source: Effects of Electrotherapy on Pain, Anxiety, Mobility, and ...

• Another study (though in patients with spinal pain broadly) found that six sessions of supra-threshold electrotherapy improved spinal mobility (flexibility) though pain and disability scores did not change significantly. This suggests more impact on movement than symptom relief. (Source: Effect of Regular Electrotherapy on Spinal Flexibility)
  Source: Effect of Regular Electrotherapy on Spinal Flexibility and ...

Hence, electrical stimulation is best viewed as a supportive modality to help with pain control, desensitization, and neuromuscular function, rather than a primary structural fix.

5. Heat Therapy

5.1 Mechanism: Why Heat Helps

Heat therapy elevates tissue temperature locally, leading to:

• Vasodilation and increased blood flow

• Reduced stiffness in connective tissues

• Lowered muscle tone and relaxation

• Slowed conduction in pain fibers (less pain sensitivity)

• Enhanced metabolic activity for healing

Methods range from superficial heat (hot packs, heat wraps, infrared) to deep heating (diathermy, shortwave, microwave, ultrasound thermal effect). The deeper methods may affect tissues beyond surface layers.

5.2 Application Modalities

• Superficial heating: e.g. hot packs, moist heat, heat wraps applied externally over neck.

• Deep heating: electromagnetic or ultrasonic modalities that deliver heat into deeper musculature, sometimes reaching spinal regions.

• The choice depends on target depth, tissue condition, and safety considerations (temperature control, duration).

5.3 Evidence for Heat Therapy

Heat therapy is commonly used in musculoskeletal pain, though evidence specific to cervical disc is limited.

• In a randomized trial, patients with chronic mechanical neck pain used a heat pad (mud-pack) daily for 20 minutes over 14 days; results showed pain relief and improved sensory function, though major functional scores did not always change significantly. (Source: Thermotherapy self-treatment for neck pain relief)
  Source: Thermotherapy self-treatment for neck pain relief — randomized controlled trial

• A broader review on superficial continuous low‑level heat in low back pain found modest short-term benefits in pain relief, flexibility, and function, suggesting heat is a safe, low-cost adjunct. (Source: Role for Superficial Heat Therapy review)
  Source: A Role for Superficial Heat Therapy in the Management ...

• However, in certain contexts (e.g. whiplash injuries), heat therapy evidence is conflicting, and its routine recommendation remains uncertain. (Source: RECOVER Injury Research Centre)
  Source: Heat Therapy – RECOVER Injury Research Centre

Given its relatively low risk, heat therapy is often used as a comfort and adjunctive intervention, especially early in pain management.

6. Integrating the Three Modalities & Clinical Strategy

6.1 Comparative Strengths and Roles

• Traction offers a mechanical unloading effect on nerve roots — potentially the most “structural” of the three methods.

• Electrical therapy is focused primarily on pain modulation and neuromuscular control.

• Heat therapy contributes to comfort, muscle relaxation, and preparatory facilitation (i.e. making tissues more responsive to subsequent interventions).

They complement each other: for instance, heat may soften tissues before traction; electrical therapy can reduce pain that impairs patient tolerance to traction or exercise.

6.2 Evidence for Combination Approaches

• Studies combining traction with exercise therapy show better outcomes than exercise alone in reducing pain in cervical radiculopathy, though evidence remains inconsistent. (Source: The Effectiveness of Cervical Traction and Exercise)
  Source: The Effectiveness of Cervical Traction and Exercise in Decreasing ...

• Some protocols integrate electro/thermal therapies plus manual therapy or spinal manipulation, yielding superior results to single interventions. (Source: Inclusion of thoracic spine manipulation into e‑thermal program)
  Source: Inclusion of thoracic spine thrust manipulation into an electrotherapy/thermal program

Thus, a multimodal plan tailored to the individual tends to be favored in practice.

6.3 Treatment Strategy Over Time

A typical therapeutic progression might be:

1. Acute pain control: Start with heat and gentle electrical stimulation to reduce pain and muscle guarding.

2. Traction introduction: Once symptoms stabilize, apply traction (often in supine, intermittent form) to reduce nerve compression.

3. Therapeutic exercise: Combine with stretching, strengthening, postural correction, and neuromuscular retraining.

4. Maintenance: Modulate the use of all modalities (traction, heat, electrical) based on symptom changes, aiming to reduce reliance gradually.

Always monitor for adverse responses, and adjust intensity, duration, or discontinue modality when necessary.

7. Case Example: Translating Theory Into Practice

Consider a 50‑year‑old male patient presenting with neck pain radiating into the right arm, with MRI evidence of a C5–6 disc protrusion and classic nerve root irritation symptoms.

• In the first week, severe pain and guarding limit tolerance for traction. We apply heat packs and low-intensity TENS to reduce pain and relax tissues.

• In week 2, we introduce intermittent supine traction sessions (e.g. 10 minutes twice daily), adjusting force gradually.

• Concurrently, mild cervical stabilization and scapular exercises are added.

• By week 4, symptoms (pain, numbness) are substantially reduced, and traction may be reduced in frequency, with continued electrical therapy and periodic heat as needed.

• Over subsequent weeks, the plan transitions toward active rehabilitation (strength, flexibility, posture) with occasional adjunctive modalities for flare-ups.

Such phased integration is typical in clinical protocols.

8. Limitations, Contraindications, and Precautions

While these modalities are widely used, they carry caveats:

• Evidence limitations: Many studies focus on short-term outcomes; long-term effects remain uncertain.
  (Source: StatPearls, cervical traction review)
  Source: Cervical Traction – StatPearls

• Traction risks: Excessive force or inappropriate patient selection may provoke worsening symptoms, dizziness, or nerve irritation. Use is contraindicated in cases of spinal instability, severe osteoporosis, cord compression, or acute fracture.
  (Source: Cleveland Clinic summary)
  Source: What to Know About Neck Traction – WebMD / Cleveland Clinic

• Electrical therapy risks: Skin irritation, discomfort, or inadvertent stimulation risks (especially in patients with implanted devices) demand caution.

• Heat therapy risks: Burns or overheating if temperature/duration is poorly controlled; avoid in acute inflammation or in area with impaired sensation.

• In severe disc herniation with neurological deficits (e.g. motor weakness, progressive signs) or failed conservative treatment, surgical referral should be considered.

9. Conclusion

For patients with cervical disc (neck disc) problems, physical therapy is a cornerstone of nonoperative care. Traction, electrical stimulation, and heat therapies each carry unique mechanisms and strengths. Traction provides mechanical unloading, electrical therapy modulates pain and improves neuromuscular function, and heat promotes comfort and tissue readiness. The most effective outcomes typically arise from individualized, multimodal protocols rather than reliance on a single modality. Clinicians should choose parameters carefully, monitor response, and remain alert to contraindications or the need for escalation.