Musculoskeletal Pain

Pain in one arm or leg, from an injury, or start on its own.  Here we don’t describe specific body parts (knee, forearm, etc.), but rather illustrate how we can identify the body structure involved (e.g. bone, tendon, etc.), wherever it might be.  For generalized pain all over, see separate topic Body Aches.  For Back Pain or Neck Pain, see those symptoms. See also Joint Pain if it’s a joint that hurts.

First, a very brief summary, which says it all, but may seem confusing.  Then definitions of terms, body structures, and a Table which also says it all.  For more depth, and explanations of how we examine, see Musculoskeletal Pain — Full Text.

Summary

A patient has pain in an arm or leg; let’s say it’s around a joint.  We may see some swelling, but no obvious deformity.  We proceed as follows, seeking the maneuver provoking maximal pain:

1.  Be sure there’s no Bone Disease.  Inspect the limb: no obvious deformity? Palpate the bones gently.  Not tender?  Palpate more firmly.  Percuss.  Pound (within reason).  Still no tenderness?  No bone disease (so probably no x-ray).  If one spot on a bone seems tender ➙ x-ray.

2.  Passive Range of Motion (PROM) to seek joint disease or ligament injury.  We wiggle the joint (patient must relax fully).  If no problem, we bend & straighten it a bit more.  More.  If PROMs don’t hurt (except maybe when bent fully), there’s no Dislocated Joint or Inflammatory Arthritis.

• PROM hurts in only one direction, suspect a Ligament Sprain, esp. if also tender to palpation.
• Osteoarthritis may not cause pain with Passive ROM until a certain point in the range.

3.  Strength-Against-Resistance  —  Without moving the joint, we test strength in all the possible directions.  If one movement brings out the patient’s pain, that’s a Tendon Strain or Tendonitis.

• If testing strength-against-resistance causes pain over a Muscle, that’s the source.

4.  Active ROM (AROM)  —  We have patient perform this if we haven’t identified a structure yet.  If AROM of a joint hurts, but not PROM, & also not strength-against-resistance testing, it’s probably a Bursitis.  Tenderness to palpation over the bursa confirms it.

5. After trauma, beware the Compartment Syndrome. Part of limb below (distal to) injury becomes more & more numb & weak within hours after injury. Even cool. Surgical emergency! Very rare.

Definitions of Terms

• “ROM” = “Range of Motion” (movement of a joint)
• Passive ROM (PROM) = Patient relaxes, examiner moves the joint
• Active ROM (AROM) = Patient moves the joint themselves
• Percussion = Tapping, or pounding
• Palpation = Pressing or pushing on (either gently or firmly)
• Point Tenderness = Tender in just one spot
• Strength-Against-Resistance = Examiner yanks while patient resists
• Proximal = Upstream. Closer to center of body (shoulder is proximal to upper arm)
• Distal = Downstream. Further from center of body (wrist is distal to forearm)

Body Structures

Here’s a list of body structures, and the findings on physical exam lead us to identify them as the source of pain.  See also our handy little reference table below, and a crude Anatomical Sketch of Musculo-Skeletal Structures below.

Note that the strategy outlined here is relative; we focus on the maneuver which elicits the most tenderness. Also, patients must cooperate; serious athletes usually do this well. But many people, so traumatized by pain, simply say everything “hurts,” which doesn’t help us narrow things down.

TABLE — The Musculoskeletal Exam

xxxxInvolved Structure   a) Bone x x x  b) Joint c) Ligament d) Muscle x x e)Tendon x x x f) Bursa x x g) Fascia (Compartments) x x x x x h) Skin / subcutaneous tissue i) Blood Vessels x j) Nervesx x

xxxxxxFunction a) Give structure to body x x x b)Space between bones c) Tie bone to bone across joint d) Power source to move distal part of limb x e) Connect muscle to distal bone (across a joint) x x f) Protect muscle and tendon from bony prominences x g) Separation and organization of anatomic structures x x x h) Protection & beauty i) Carry blood to hands / feet x j) Allow hands / feet to movex x

xxxxExam Findings a) Point tenderness to percussion Radiating tenderness to percussion. b) Tender to any passive ROM. c) Tender to passive ROM that stretches the injury. d) Tender to palpation. Tender to strength-against-resistance (at site of muscle). e) Tender to strength-against-resistance (across joint, at site of tendon), Tender to palpation. f) Tender to all Active ROM Not to Passive ROM, May be Painful at Rest. g) Compartment Syndrome: Progressive pain soon after trauma.  Distal numbness/tingling Distal losses of sensation or motor strength. h) Tender to superficial palpation. i) Hand / foot cool / blue No pulse j) Loss of movement that’s not due to painx x

Injured Arm & Leg Emergencies

** Obviously deformed limb — Call 911

** Fractured femur (thigh bone) — Can cause major hemorrhage. Call 911

** Compartment Syndrome — Tingling / loss of movement in hand / foot distal to injury
……….x • Progressing over hours. Worst is when hand / foot turns cold or blue
……….x • Needs emergency surgery to prevent permanent nerve / tendon / artery loss

** Dislocated Joint — Call 911
……….x • Severe pain, can’t move joint at all (neither AROM nor PROM)
……….x• Needs emergency treatment to replace joint in socket, prevent permanent nerve damage

** Open Fracture — broken bone with a wound directly over it
……….x • Needs IV antibiotics ASAP to prevent bone infection

** Don’t Forget the Neck !!! — broken necks can paralyze !!! Call 911.
……….x • No matter how bad the arm / leg looks, if head or neck injury, Check the Neck

X-Rays & MRI’s

We only X-Ray if suspect Bone Disease or Osteoarthritis. Almost nothing else shows on X-ray.

MRI — can show torn ligaments, tendons, cartilage, and more. BUT — many false-positive findings.

• We only order if history and physical exam indicate a specific abnormality, not “just to see”
• Usually not worth ordering unless patient would opt for surgery

See Musculoskeletal Pain — Full Text for more in-depth explanations and discussions.