Study guide
15.3 Mechanical Modalities (Traction, Compression, CPM)
BOC Certification Exam for Athletic Trainers ATC
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1 Introduction & Exam Overview
1.1 Current BOC ATC Exam Facts 1.2 Item Types, Clinical Reasoning & Study Planning
2 Screening, PPE & Risk Identification
2.1 Pre-Participation Physical Examination 2.2 Injury Surveillance, Epidemiology & Intrinsic/Extrinsic Risk 2.3 Protective Equipment Fitting & Safety Standards
3 Prevention Programs, Facility Safety & Health Literacy
3.1 Evidence-Based Injury Prevention Programs 3.2 Facility, Playing Surface & OSHA Safety 3.3 Health Literacy, Communication & Patient Advocacy
4 Environment & Wellness
4.1 Heat Illness Prevention & WBGT Monitoring 4.2 Lightning, Cold, Altitude & Air Quality 4.3 Nutrition, Hydration & Sleep 4.4 Wellness Promotion & Mental Health
5 History, Exam Framework & Neurological Screen
5.1 Patient History & Interview Techniques 5.2 Physical Examination Framework & Diagnostic Accuracy 5.3 Neurological Screening & Cranial Nerve Assessment
6 Upper Extremity & Cervical/Thoracic Spine Assessment
6.1 Shoulder Complex Assessment 6.2 Elbow, Wrist & Hand Assessment 6.3 Cervical & Thoracic Spine Assessment
7 Lumbar Spine, Hip & Knee Assessment
7.1 Lumbar Spine Assessment 7.2 Hip, Groin & Pelvis Assessment 7.3 Knee Joint Assessment
8 Foot/Ankle, Imaging, General Medical & Diagnosis
8.1 Foot & Ankle Assessment 8.2 Diagnostic Imaging & Clinical Decision Rules 8.3 Cardiovascular, Pulmonary, Abdominal & Dermatologic Assessment 8.4 Clinical Diagnosis, Differential Diagnosis, Plan of Care & Patient Education
9 Emergency Action Plans, Scene Assessment & Triage
9.1 Emergency Action Plans 9.2 Scene Assessment & Safety 9.3 Triage & Primary/Secondary Survey
10 Cardiac, Airway & Medical Collapse
10.1 Sudden Cardiac Arrest, High-Performance CPR & AED 10.2 Airway & Breathing Management 10.3 Medical Collapse: Anaphylaxis, Asthma, Diabetes, Sickle Cell & ECAST
11 Spine, Hemorrhage & Head Trauma
11.1 Cervical Spine Trauma, Equipment Removal & Spine Boarding 11.2 Hemorrhage Control, Shock, Fractures & Dislocations 11.3 Acute Head Trauma & Concussion Sideline Triage
12 Environmental Catastrophe & Mental Health Emergencies
12.1 Exertional Heat Stroke, Hyponatremia & Cold Injury Emergencies 12.2 Mental Health Emergencies, Suicide Risk & Transfer of Care
13 Rehab Design & Therapeutic Exercise
13.1 Tissue Healing Stages & Rehabilitation Plan of Care 13.2 Patient Education, Adherence & Shared Decision-Making 13.3 Therapeutic Exercise: ROM, Flexibility & Strength
14 Neuromuscular Training, Functional Testing & Return-to-Play
14.1 Neuromuscular Control, Plyometrics & Sport-Specific Training 14.2 Functional Testing & Return-to-Play Criteria 14.3 Concussion Return-to-Learn & Return-to-Sport
15 Therapeutic Modalities
15.1 Cryotherapy & Thermotherapy 15.2 Electrotherapy & Therapeutic Ultrasound 15.3 Mechanical Modalities (Traction, Compression, CPM)
16 Manual Therapy, Pharmacology & Medical Management
16.1 Manual Therapy Techniques 16.2 Taping, Bracing & Orthoses 16.3 Pharmacological Principles & Common Medications 16.4 Managing General Medical Conditions During Activity
17 Documentation, Privacy, Policy & Quality
17.1 Clinical Documentation & Medical Records 17.2 HIPAA, FERPA & Privacy 17.3 Policies, Quality Improvement & Budgeting
18 Legal, Ethics & Professional Practice
18.1 State Practice Acts, Scope of Practice & Legal Risk 18.2 BOC Standards, Ethics, EBP & Interprofessional Care
15.3 Mechanical Modalities (Traction, Compression, CPM)
Key Takeaways Explain This Topic AI
Acute or suspected DVT contraindicates intermittent pneumatic compression until the athlete is medically cleared; compressing a clot can embolize. Keep cuff pressure below diastolic blood pressure.
Commonly taught traction doses: cervical trial about 10–15 lb, distraction about 20–30 lb (~7–10% body weight); lumbar stretch/spasm about 25% body weight, separation about 50% on a split table.
Do not apply lumbar traction in pregnancy or to an unstable spine. Cervical traction: screen rheumatoid atlantoaxial instability, osteoporosis, TMJ dysfunction, and dentures (remove them; prefer occipital harness).
CPM after surgery is physician-directed (often TKA). Long-term outcome evidence is modest; it is not a substitute for active rehabilitation. Massage guns are mechanical devices with nerve, bone, acute-injury, and DVT precautions.
Trap: lumbar traction on a pregnant patient or unstable spine. Gravity-assisted inversion is still traction—same screens apply.
Last updated: August 2026
Quick Answer: Intermittent pneumatic compression (IPC) is contraindicated with acute or suspected DVT until cleared. Cervical traction for distraction is commonly about 20–30 lb ; lumbar separation is often about 25–50% of body weight . Do not lumbar-traction a pregnant athlete or an unstable spine . CPM is physician-directed . Trap: lumbar traction in pregnancy or on an unstable segment.
Mechanical modalities apply force : compression, distraction, or passive motion. Task 0404 still applies—parameters, screens, and documentation—not a 'set it and walk away' cycle.
Intermittent compression and cold-compression units
IPC inflates a sleeve in distal-to-proximal chambers (sequential) or as a single chamber, then deflates so the veins refill. Clinic goals: post-traumatic or postoperative edema , residual-limb shaping, and, in medical settings, DVT prevention in immobilized patients . Athletic recovery boots are the same physics with marketing.
Commonly taught parameters (Cameron/Prentice-style; follow the device manual):
- Setting Typical teaching range Why it matters
- Pressure, upper extremity About 30–60 mmHg Below diastolic blood pressure so arteries still fill
Pressure, lower extremity About 40–80 mmHg Athletic recovery units may go higher; still respect arterial disease and pain
On:off Often about 3:1 (for example 90 s inflate / 30 s deflate) Deflation is when arterial inflow and venous refill occur
Time About 20–30 minutes (lymphedema protocols can be longer) Recheck skin, fingers/toes, and symptoms
Measure blood pressure first. A cuff above diastolic pressure is an arterial tourniquet with extra steps. Elevate the limb. Use a stockinette. Watch fingers and toes for color and sensation.
DVT is the headline contraindication. If a clot is present or reasonably suspected (unilateral calf swelling, warmth, positive Wells-type picture, recent surgery plus dyspnea), do not compress that limb until vascular medicine has ruled out or treated the clot. IPC on an existing DVT can embolize . After a cleared, treated DVT, follow the physician—do not freelance.
Other IPC stops: decompensated heart failure / pulmonary edema (you are pushing fluid centrally), acute infection or open wound in the sleeve, acute fracture you are not ready to compress, compartment syndrome , and severe peripheral arterial disease . Game Ready–style cold-compression units add cryotherapy contraindications (Raynaud, cold urticaria, regenerating nerve) on top of the DVT rule. They do not get a free pass because the water is cold.
Traction: cervical versus lumbar, mechanical versus gravity
Traction applies a distractive force along the long axis of the spine. Proposed effects, as taught: separate vertebrae a few millimeters, unload a disc bulge, gap facet joints, stretch muscle and ligament, and reduce radicular compression. Evidence for lasting disc reduction is mixed ; many athletes get temporary relief. Dose it as a trial, not as a cure for every backache.
Mechanical traction uses a motorized unit and harnesses (occipital/chin for cervical; thoracic and pelvic belts for lumbar) on a table, often a split table for lumbar so friction does not eat the force. Manual traction is the AT's hands—useful as a test dose. Gravity-assisted traction (inversion table, hanging from a stall bar, some home pneumatic devices) uses body weight. It is still traction. Pregnancy, unstable spine, uncontrolled hypertension, and glaucoma/orbital issues still matter. Inversion is not 'natural' and therefore safe.
Textbook-conventional forces
These are commonly taught Kisner/Colby and Prentice numbers, not a license to yank.
Goal Cervical (typical teaching) Lumbar (typical teaching)
First-visit trial / muscle spasm About 10–15 lb (do not start at 30 lb on a 110-lb gymnast) About 25% of body weight (enough to beat table friction on a split table)
Joint distraction / disc About 20–30 lb , often framed as ~7–10% of body weight ; many sources cap cervical near 30 lb About 50% of body weight (range often ~30–60% as tolerated); older texts quote 65–200 lb depending on body size
Angle Upper cervical nearer neutral ; lower cervical often 20–30° flexion Flexion bias (supine 90/90) for stenosis/facet; some disc protocols use prone/neutral
Mode Intermittent (often ~3:1 hold:rest) common for disc; static sometimes for spasm Intermittent common for disc herniation teaching; static for some stiffness protocols
Time About 10–20 minutes About 10–20 minutes
Position and pathology. A locked facet (acute wry neck, sharp local pain, guarded rotation) may respond to a gentle flexion-and-rotation bias or a small distractive trial— not a maximum-poundage yank. A disc herniation with progressive neurologic deficit, saddle anesthesia, or myelopathy is not a traction candidate; that is a medical emergency. Midline massive herniation and worsening radiculopathy are precautions/contraindications in most EPA lists. If symptoms peripheralize (pain moves farther down the limb), stop and regress —that is the mechanical-diagnosis cousin of a failed traction trial.
Traction screens the exam loves
Do not apply traction (especially lumbar) in:
Pregnancy (lumbar belts over a gravid abdomen; ligamentous laxity; this is a hard teaching contraindication )
Unstable spine (fracture, acute severe sprain, postsurgical instability, high-grade spondylolisthesis as directed by the physician)
- Rheumatoid arthritis of the cervical spine ( atlantoaxial instability —a chin-strap pull can be catastrophic)
- Osteoporosis / osteopenia sufficient to fracture
Spinal infection, malignancy, myelopathy , uncontrolled hypertension, severe anxiety/claustrophobia that makes the harness unsafe
Cervical-specific: TMJ dysfunction and dentures . A mandibular (chin) strap loads the jaw. Remove dentures , ask about TMJ, and prefer an occipital harness that unloads the chin. Vertebral-basilar insufficiency symptoms (dizziness, drop attacks, visual change) with cervical positioning mean stop .
Herniation versus facet is a precaution story , not a single poundage. Facet-oriented pain often likes flexion and intermittent motion. Acute, angry disc with neurological worsening does not get 50% body-weight lumbar traction because a protocol PDF said 'disc.'
CPM and percussive devices
Continuous passive motion (CPM) is a motorized cradle that cycles a joint through a physician-set arc, classically after total knee arthroplasty and some cartilage or ACL procedures. Salter's animal work argued that motion nourishes cartilage. Human Cochrane-style reviews after TKA show at most small, short-term ROM differences of questionable clinical importance. Teach it as physician-directed adjunctive motion , not as a replacement for quadriceps activation, swelling control, and gait. Set the device to the written ROM, check skin and incision, and do not crank flexion past the surgeon's lock because the athlete is 'tough.'
Massage guns (percussive/vibration devices) are mechanical modalities . Limited high-quality outcome data support them as recovery toys more than as disease-modifying therapy. Precautions still count: do not percuss over acute injury or fracture , DVT , bony prominences , the anterior neck , the spine/spinous processes with aggressive force, impaired sensation , anticoagulation (bruise risk), or an open area. A gun on a calf 'knot' that is actually a DVT is a disaster.
Putting the mechanical cluster together
Screen first: pregnancy, DVT, instability, RA neck, osteoporosis, pacemaker (if combining with e-stim), skin, and cognition. Then pick the force that matches the goal —edema emptying is not vertebral separation, and a CPM arc is not traction. Reassess symptoms during the bout; peripheralizing pain, dyspnea, calf pain, jaw pain, or dizziness ends the session.
Exam trap: lumbar traction on a pregnant patient or an unstable spine. A second trap is treating gravity-assisted inversion as exempt from the same list. A third is using IPC to 'treat' a DVT . Mechanical force is only as safe as the screen.