NSG210 Hinkle Ch. 35: Assessment of Musculoskeletal Function

Source: Hinkle & Cheever, Brunner & Suddarth’s Medical-Surgical Nursing 15e, Chapter 35, pp. 1096-1112 (textbooks/HINKLE_MS_CH35.pdf, also in textbooks/exam03/). Week 08 reading (alterations in activity and rest); on Exam 3. Numbering note: the syllabus lists “Ch. 36” for musculoskeletal assessment, which is the 16th edition number; in the 15th edition it is Ch. 35 (see nsg210-textbook-chapter-crosswalk). Disorders built on this chapter: nsg210-hinkle-ch34-inflammatory-rheumatic-disorders, nsg210-hinkle-ch36-musculoskeletal-disorders, nsg210-hinkle-ch37-musculoskeletal-trauma. Lecture slides: raw/nsg210_AlterationActivityRestRheumaticDiseases2026.md, nsg210-week-08-rheumatic-diseases-lecture.

Learning Outcomes

1. Describe the basic structure and function of the musculoskeletal system.
2. Discuss the significance of the health history to musculoskeletal assessment.
3. Recognize and evaluate the major manifestations of musculoskeletal dysfunction from history and physical findings.
4. Explain indications, patient preparation and nursing implications for common musculoskeletal tests and procedures.

Key Terms

• Atonic: without tone; denervated muscle that atrophies
• Atrophy: decrease in muscle size. Hypertrophy: increase in muscle size
• Bursa: fluid-filled sac in connective tissue near joints
• Callus: cartilaginous or fibrous tissue at a fracture site
• Cancellous (trabecular) bone: latticelike. Cortical bone: compact
• Cartilage: tough, elastic, AVASCULAR tissue at bone ends
• Clonus: rhythmic contractions of a muscle
• Contracture: abnormal shortening of muscle, joint or both (fibrosis)
• Crepitus: grating or crackling sound or sensation (broken bone ends or irregular joint surfaces)
• Diaphysis: shaft of a long bone. Epiphysis: end of a long bone
• Effusion: excess fluid in a joint
• Fascia (epimysium): fibrous tissue covering and separating muscles
• Fasciculation: involuntary twitch of muscle fibers
• Flaccid: limp, no tone. Spastic: greater than normal tone
• Isometric contraction: tension increases, length unchanged, no joint motion. Isotonic contraction: muscle shortens, tension unchanged, joint moves
• Kyphosis: increased convex curve of the thoracic spine. Lordosis: increased concave curve of the lumbar spine. Scoliosis: lateral curve
• Ligament: collagen bundles connecting BONE to BONE. Tendon: fibrous cord connecting MUSCLE to BONE
• Osteoblast: forms bone. Osteoclast: resorbs bone. Osteocyte: mature bone cell
• Osteon: microscopic functional unit of bone (haversian system)
• Osteopenic: bone mass below normal
• Paresthesia: burning, tingling or numbness
• Periosteum: fibrous covering of bone. Endosteum: thin vascular membrane lining the marrow cavity
• Remodeling: simultaneous resorption and formation that maintains bone
• Synovium: joint membrane that secretes lubricating fluid
• Tone (tonus): normal resting tension in muscle

I. Overview

• System: bones, joints, muscles, tendons, ligaments, bursae. Functions: support and protect, movement, heat production, venous return (muscle massage of veins), blood cell production, mineral storage (calcium, phosphorus, magnesium, fluoride). More than 98% of body calcium is in bone
• Components are integrated: disease of one affects the others (septic arthritis destroys articular surfaces and causes local muscle atrophy)
• Musculoskeletal disorders are a leading cause of US disability (over $980 billion a year); arthritis is the chief cause (54.4 million adults, projected 78 million by 2040)

II. Skeletal System

A. Bone types and structure

• 206 bones; four shapes:
  • Long (femur): diaphysis of cortical bone; epiphyses of cancellous bone; epiphyseal (growth) plate in children, calcified in adults; ends covered by articular cartilage
  • Short (metacarpals, ankle): cancellous bone covered by cortical bone
  • Flat (sternum, skull): cancellous bone between compact layers; important sites of hematopoiesis and protection
  • Irregular (vertebrae, jaw)
• Cortical bone where support is needed; cancellous bone where hematopoiesis and bone formation occur
• Bone cells: osteoblasts secrete matrix (collagen and ground substance, mineralized with calcium and phosphorus); osteocytes in lacunae maintain bone; osteoclasts in Howship lacunae dissolve and resorb bone
• Osteon (haversian system): central haversian canal with a capillary, ringed by lamellae; osteocytes in lacunae fed by canaliculi
• Periosteum: nourishes bone, allows growth, carries nerves, vessels and lymphatics, anchors tendons and ligaments
• Red marrow (adults: sternum, ilium, vertebrae, ribs) makes RBCs, WBCs and platelets; adult long bones contain yellow fatty marrow
• Bone is highly vascular (metaphyseal, epiphyseal, periosteal and nutrient arteries; Volkmann canals). Loss of blood supply causes necrosis

B. Bone formation and maintenance

• Ossification: matrix forms and calcium phosphate crystals (hydroxyapatite) bind to collagen. Minerals give strength; collagen gives resilience
• Remodeling: bone added faster than removed in childhood and adolescence until peak bone mass at about age 20; complete skeletal turnover about every 10 years
• Factors in the balance: physical activity, calcium intake, and hormones (calcitriol, PTH, calcitonin, thyroid hormone, cortisol, growth hormone, estrogen, testosterone)
• Weight-bearing activity stimulates formation; bed rest and immobility increase resorption and calcium loss, so bones become osteopenic and fracture easily
• Calcium 1,000 to 1,200 mg/day for adults (low-fat dairy, fortified juice, cereals, bread)
• Vitamin D 600 IU/day for young adults; 800 to 1,000 IU/day at age 50 and older (fortified milk and cereal, egg yolks, saltwater fish, liver)

Hormones:

• Calcitriol (active vitamin D): raises blood calcium by increasing GI absorption; mineralizes osteoid. Deficiency causes poor mineralization, deformity, fracture
• PTH: low blood calcium raises PTH, which mobilizes calcium from bone (demineralization, bone cysts)
• Calcitonin (thyroid): released for HIGH blood calcium; inhibits resorption and increases calcium deposit in bone
• Excess thyroid hormone (Graves disease) and excess cortisol both increase resorption and decrease formation; long-term corticosteroids (prednisone) cause steroid-induced osteopenia and fractures
• Growth hormone and IGF-1 drive childhood growth; low levels with aging contribute to osteopenia
• Estrogen stimulates osteoblasts and inhibits osteoclasts; testosterone builds bone and muscle and converts to estrogen in fat (protects older men)
• RANKL (made by osteoblasts and activated T cells) turns on osteoclasts; osteoprotegerin (OPG) blocks RANKL. Inflammation can override OPG and cause bone loss

C. Bone healing

• Bone regenerates itself rather than scarring
• Primary healing: with internal or external fixation the fragments touch and heal by cortical (haversian) remodeling with little callus
• Four stages of simple fracture repair:
  1. Hematoma formation (days 1 to 2): bleeding, vasoconstriction, clot; cytokines start healing; fibroblasts, angiogenesis, granulation tissue
  2. Inflammatory phase: granulation tissue; fibroblasts and osteoblasts form a fibrocartilaginous soft callus bridging the fragments; maximum girth by week 2 to 3 but NOT strong enough for weight bearing
  3. Reparative phase (starts week 3 to 4, continues to firm bony union): mature bone replaces the callus; fracture feels immovable and looks aligned on x-ray; usually safe to remove a cast
  4. Remodeling: osteoclasts remove necrotic bone; compact bone replaces spongy bone; months to years; a thickened area may remain
• Serial x-rays track healing. Healing rate depends on bone type, blood supply, fragment condition, immobilization, age and health. Immobilize until x-ray shows ossification

III. Articular System (Joints)

• Synarthrosis (fibrous): immovable (skull sutures)
• Amphiarthrosis (cartilaginous): limited motion (vertebral joints, symphysis pubis)
• Diarthrosis (synovial): freely movable
  • Ball-and-socket (hip, shoulder): full freedom of movement
  • Hinge (elbow, knee): flexion and extension in one direction
  • Saddle (base of the thumb): two planes at right angles
  • Pivot (radius and ulna): rotation, such as turning a doorknob
  • Gliding (carpal bones): limited movement in all directions
• Synovial joint: hyaline cartilage on bone ends; joint capsule lined by synovium, which secretes lubricating, shock-absorbing synovial fluid; some have fibrocartilage discs (medial meniscus of the knee)
• Ligaments and tendons crossing the joint provide stability; interosseous ligaments (cruciate ligaments of the knee) add anterior and posterior stability. Ligaments TEAR rather than stretch under excess stress
• Bursae (elbow, shoulder, hip, knee) cushion movement; bursitis causes pain, swelling and limited motion

IV. Skeletal Muscle System

• Muscles attach by tendons; made of fasciculi wrapped in fascia; more fasciculi, more precise movement
• Functions: movement, posture, heat production
• Contraction: nerve impulse at the motor end-plate leads to an action potential, release of calcium from the sarcoplasmic reticulum, and actin and myosin sliding in the sarcomere. Relaxation when calcium is pumped back. No calcium, no contraction
• Isometric (pushing a wall; almost all energy released as heat) vs isotonic (flexing the forearm). Walking combines both
• Energy: ATP from oxidative metabolism at rest; strenuous activity shifts to anaerobic lactic acid. Fatigue comes from glycogen depletion and lactic acid buildup. Shivering generates heat
• Red muscles (high myoglobin) contract slowly and powerfully (respiratory, postural); white muscles contract quickly (extraocular)
• Tone: maintained by partially contracted fibers, monitored by muscle spindles; minimal in sleep, increased with anxiety
  • Upper motor neuron lesions (cerebral palsy): increased tone, spasticity, hyperactive reflexes
  • Lower motor neuron lesions (muscular dystrophy): atonic, flabby, atrophied muscle
• Actions: prime mover causes the motion; synergists assist; antagonists oppose and must relax (biceps flexes the elbow, triceps is the antagonist)

Exercise, disuse and repair:

• Hypertrophy: repeated near-maximum tension enlarges existing fibers (not more fibers); persists only with continued exercise
• Disuse and age: fibrous tissue replaces contractile tissue (atrophy); bed rest and immobility cause loss of mass and strength
• During immobilization (cast, traction, bed rest): isometric exercises of the immobilized part, especially quadriceps setting (tighten the thigh) and gluteal setting (tighten the buttocks) to preserve muscles needed for walking; active and resistance exercise of uninjured parts
• Injured muscles need rest and immobilization, then progressive exercise

V. Gerontologic Considerations (Table 35-1)

• Women lose more bone than men; menopause (estrogen loss) and inactivity drive osteoporosis
• Old compensated problems (post-polio) may resurface as compensation fails
• Hand and wrist disorders (osteoarthritis, trigger finger, carpal tunnel) are common; older adults often delay care until ADLs suffer (Nursing Research Profile). Screen for them
• Healthy, active lifestyle slows age-related changes

VI. Health History

• Present illness: onset, character, severity, location, duration, frequency, associated complaints, aggravating and relieving factors, progression, family history

Pain:

• Bone pain: dull, deep, boring ache; not related to movement; may disturb sleep
• Muscle pain: soreness or aching (“cramps”)
• Fracture pain: sharp, piercing; relieved by immobilization
• Sharp pain also from bone infection with spasm or nerve pressure
• Joint pain: around or in the joint; worse with movement
• Rest relieves most musculoskeletal pain
• Pain that increases with activity: sprain, strain or compartment syndrome
• Steadily increasing pain: infection (osteomyelitis), malignant tumor or neurovascular complication
• Radiating pain: pressure on a nerve root
• Timing: inflammatory rheumatic disease worst in the morning on waking; tendonitis worse early morning, eases by midday; osteoarthritis WORSENS as the day goes on
• Assess alignment, symmetry and deformity; inflammation (swelling, warmth, tenderness, redness); pressure from traction, linens, casts or appliances; skin tension at pin sites. Uncontrolled pain leads to withdrawal and dependence

Altered sensation:

• Paresthesias (burning, tingling, numbness) from nerve pressure or circulatory impairment
• Ask: type of sensation, comparison with the unaffected limb, onset and progression, associated pain

Past, social and family history: occupation (lifting), exercise, alcohol, tobacco, calcium and vitamin D intake, comorbidities (diabetes, heart disease, COPD, infection, disability), genetic conditions, prior trauma, falls.

FRAX (Fracture Risk Assessment Tool, WHO 2008): predicts 10-year risk of hip or major osteoporotic fracture (spine, forearm, shoulder). Inputs:

• Age (risk rises with age); female sex; LOW BMI
• Previous fracture; parental hip fracture
• Current smoking; current corticosteroid use; rheumatoid arthritis; 3 or more alcoholic drinks a day
• Secondary causes: type 1 diabetes, osteogenesis imperfecta, untreated long-standing hyperthyroidism, hypogonadism or premature menopause, chronic malnutrition or malabsorption, chronic liver disease
• Hip BMD can be added but is not required
• Assess men and postmenopausal women over 50, people with known low BMD, and people with secondary risk factors

Genetics (Chart 35-2): autosomal dominant (achondroplasia, nail-patella syndrome, osteogenesis imperfecta, polydactyly, van der Woude); Duchenne and Emery-Dreifuss muscular dystrophy are X-linked; also Marfan, Ehlers-Danlos, Stickler, ALS, spina bifida. Clues: short stature (achondroplasia), tall stature with long fingers, pectus excavatum or scoliosis (Marfan), unexplained fractures, hypermobile joints, hypotonia.

VII. Physical Assessment

The nursing assessment is primarily FUNCTIONAL, focused on the ability to perform ADLs. Uses inspection and palpation of posture, gait, bone integrity, joint function, muscle strength and size, skin and neurovascular status.

A. Posture and spine

• Normal: thoracic convex; cervical and lumbar concave
• Kyphosis (hunchback): degenerative disease, osteoporotic fractures, trauma, neuromuscular disease
• Lordosis (swayback): tight low back muscles, visceral fat, pregnancy
• Scoliosis: congenital, idiopathic or from paraspinal muscle damage (muscular dystrophy). Signs: lateral curve, uneven shoulders, asymmetric waist, prominent scapula that is accentuated by bending forward
• Exam: expose back, buttocks and legs; inspect from behind and the side; compare shoulder and iliac crest heights; check standing, bending forward and bending backward (support the posterior iliac spine)
• Measure adult height at every screening (loss from cartilage thinning and compression fractures)

B. Gait

• Patient walks away from the examiner; observe smoothness and rhythm
• Limp: usually painful weight bearing (patient can point to the spot) or a shorter leg (pelvis drops on the affected side)
• Knee should flex during normal gait
• Neurologic gaits: spastic hemiparesis (stroke), steppage (lower motor neuron disease), shuffling (Parkinson disease)

C. Bone integrity

• Compare symmetric parts; note deformity, tumors, shortening, amputation, malalignment
• Fracture signs: abnormal angulation, motion where there is no joint, crepitus. Minimize movement of fragments
• Compare with the unaffected limb: movement, sensation and motion of each finger or toe, skin temperature, color distal to the injury (pale, dusky, mottled, cyanotic), capillary refill, distal pulse, edema, constrictive devices, effect of elevation or position

D. Joint function

• Assess ROM (active and passive), deformity, stability, tenderness, nodules; goniometer for precise ROM
• Limited ROM: deformity, joint disease or contracture
• Painful or limited joint: check for effusion, swelling and warmth (inflammation). Effusion is suspected when bony landmarks are obscured; the KNEE is the most common site
  • Balloon sign: milk the medial and lateral knee downward; fluid fills the space below the patella
  • Ballottement: milk downward, push the patella toward the femur and watch for fluid return above the patella; patella elevates with large effusions
  • Suspected fluid or inflammation: refer to an orthopedist or rheumatologist
• Deformity: contracture, dislocation (complete separation of joint surfaces), subluxation (partial separation), or disrupted supporting structures (may need a brace)
• Palpate during passive motion: smooth is normal; a snap may be a ligament slipping over bone; crepitus with roughened arthritic surfaces

Nodules:

E. Muscle strength and size

• Assess strength, coordination, size and ability to change position
• Weakness of a muscle group: polyneuropathy, electrolyte imbalance (potassium, calcium), myasthenia gravis, polio, muscular dystrophy
• Tone: palpate while passively moving the relaxed limb
• Strength: maneuvers with and without resistance (flex the biceps against resistance); a handshake estimates grasp
• Clonus: elicited by sudden, forceful, sustained dorsiflexion of the foot or extension of the wrist
• Fasciculations may be visible
• Girth: measure the unaffected limb as the reference; same site and position, muscle at rest, at the maximum circumference; record the distance from a landmark (for example, 10 cm below the medial knee) and mark the skin. A difference greater than 1 cm is significant

F. Skin

• Edema, temperature (warm = increased perfusion or inflammation; cool = decreased perfusion), color, cuts, bruises, signs of poor circulation

G. Neurovascular status (CMS: circulation, motion, sensation)

• Frequent checks for patients with musculoskeletal disorders, especially fractures
• Compartment syndrome: pressure in a muscle compartment cuts off microcirculation, causing nerve and muscle anoxia and necrosis; function can be lost permanently if anoxia lasts more than 6 HOURS (details in nsg210-hinkle-ch37-musculoskeletal-trauma)

Chart 35-4, indicators of peripheral neurovascular dysfunction:

• Circulation: pale, cyanotic or mottled color; cool temperature; capillary refill more than 3 seconds
• Motion: weakness, paralysis
• Sensation: paresthesia, unrelenting pain, pain on PASSIVE STRETCH, absence of feeling

Chart 35-3, peripheral nerve function:

VIII. Diagnostic Evaluation

A. Imaging

• X-ray: density, texture, erosion, cortical changes; joint fluid, spurs, narrowing. Multiple views; serial films for healing
• CT (with or without contrast): tumors, soft tissue, ligament and tendon injury, severe trauma; fractures hard to see on x-ray (acetabulum)
• MRI: magnetic field and radio waves; torn muscles, ligaments and cartilage, herniated discs, hip and pelvic problems. Painless, noisy (knocking), 30 to 90 minutes. Open MRI is easier for claustrophobia but gives lower-quality images

Quality and Safety Nursing Alert, MRI:

• Remove jewelry, hair clips, hearing aids, credit cards and other metal (projectiles, burns; cards erased)
• Most metal implants and clips, and nonremovable cochlear implants, are contraindications
• Remove transdermal patches with aluminized backing (nicotine, nitroglycerin, scopolamine, clonidine) because they cause burns; notify the provider before removing them

Nursing for all imaging studies: the patient must lie still; assess for pregnancy, claustrophobia, inability to hold the position, metal implants; assess for allergies before contrast (CT, MRI, arthrography).

• Arthrography: contrast or air injected into a joint, which is moved through ROM during x-rays; contrast leaking out shows a tear. Afterward: compression bandage if ordered, rest the joint 12 hours, avoid strenuous activity until cleared, mild analgesia and ice; clicking or crackling for 24 to 48 hours is normal until the contrast is absorbed
• Bone densitometry: DXA (DEXA) is the most common and best predicts fracture risk (hip and spine); QCT and quantitative ultrasound; peripheral DXA (forearm, finger, heel) is less accurate for hip and spine risk. BMD can differ by site
• Bone scan: IV radioisotope, scan 2 to 3 hours later; increased uptake (“hot spots”) in osteosarcoma, metastases, osteomyelitis, some fractures, nonhealing fractures, aseptic necrosis; detects disease before x-ray (stress fracture with negative x-ray). Nursing: ask about allergies, pregnancy and breastfeeding; may feel flushing or warmth; no radiation hazard; drink plenty of fluids; EMPTY THE BLADDER before the scan (a full bladder blocks pelvic images)

B. Procedures

• Arthroscopy: fiberoptic scope in the OR under local or general anesthesia; joint distended with saline; allows biopsy and repair. Complications (rare): infection, hemarthrosis, neurovascular compromise, thrombophlebitis, stiffness, effusion, adhesions, delayed healing. After: compression dressing, ice, keep the joint extended and elevated, neurovascular checks, analgesia, avoid strenuous use; report fever, bleeding, swelling, numbness, cool skin
• Arthrocentesis (joint aspiration): to examine synovial fluid or relieve effusion pain; may inject anti-inflammatory drugs; aseptic technique, sterile dressing; infection risk. Normal synovial fluid is clear, pale, straw-colored and scanty. Diagnoses septic arthritis and other arthropathies; blood (hemarthrosis) suggests trauma or a bleeding disorder
• Electromyography (EMG): needle electrodes record muscle and nerve electrical activity; evaluates weakness, pain and disability and tells muscle from nerve problems; used when nerve function has not returned within 4 MONTHS of injury. Before: ask about ANTICOAGULANTS (usually contraindicated; bleeding into muscle) and skin infection; notify the provider; no lotions or creams that day. After: warm compresses for discomfort
• Biopsy (bone, marrow, muscle, synovium): explain and promise analgesia; monitor for edema, bleeding, pain, hematoma, infection; ice; antibiotics and analgesics; report redness, bleeding, pain, fever or chills. Hair may be removed; antispasmodics may be given; ice for 24 to 48 hours

C. Laboratory studies

• Coagulation studies before surgery (bone is vascular)
• Serum calcium: altered in osteomalacia, parathyroid dysfunction, Paget disease, bone metastases, prolonged immobilization
• Serum phosphorus: inversely related to calcium; low in osteomalacia from malabsorption
• Acid phosphatase: elevated in Paget disease and metastatic cancer
• Alkaline phosphatase (ALP): elevated in early fracture healing and with increased osteoblast activity (bone metastases)
• Thyroid studies, calcitonin, PTH, vitamin D for bone metabolism
• Creatine kinase (CK) and AST: elevated with muscle damage
• Serum osteocalcin: rate of bone turnover
• Urine calcium: increased with bone destruction (parathyroid dysfunction, bone metastases, multiple myeloma)
• Bone resorption markers (osteoclast activity): urine NTx and deoxypyridinoline (Dpd)
• Bone formation markers (osteoblast activity): serum bone-specific ALP, osteocalcin, PINP

High-Yield Numbers

• 206 bones; more than 98% of body calcium in bone
• Peak bone mass by about age 20; full skeletal turnover every 10 years; bone loss begins after 30
• Calcium 1,000 to 1,200 mg/day; vitamin D 600 IU (young adults), 800 to 1,000 IU (50 and older)
• Fracture healing: hematoma days 1 to 2; soft callus maximum girth by week 2 to 3 (not weight bearing); reparative phase from week 3 to 4 (cast removal usually safe); remodeling months to years
• Capillary refill normal within 3 seconds; more than 3 seconds is abnormal
• Compartment syndrome: permanent loss after more than 6 hours of anoxia
• Limb girth difference greater than 1 cm is significant
• FRAX: 10-year fracture risk; alcohol 3 or more drinks a day is a risk factor; screen men and postmenopausal women over 50
• MRI 30 to 90 minutes; bone scan 2 to 3 hours after isotope
• Arthrogram: rest joint 12 hours; clicking 24 to 48 hours is normal
• EMG if nerve function has not returned in 4 months

Priority Nursing Actions and Red Flags

• Neurovascular checks (CMS) on any extremity injury, cast or traction; compare with the other side
• Pain on passive stretch, unrelenting pain out of proportion, paresthesia, pallor, coolness or delayed capillary refill: suspect compartment syndrome and notify the provider immediately
• Steadily increasing pain: think infection, tumor or neurovascular complication
• Suspected fracture: immobilize; do not move the fragments
• MRI safety: remove metal and medication patches (notify the provider first); screen for implants
• Bone scan: void before the scan; push fluids after
• EMG: hold and report anticoagulant use
• Arthroscopy: elevate, ice, compression, neurovascular checks
• Immobilized patient: quadriceps and gluteal setting exercises; weight-bearing activity protects bone
• Long-term corticosteroids or hyperthyroidism: osteopenia and fracture risk

Medications

No chapter-specific drug therapy. Drug-related points:

• Long-term corticosteroids (prednisone): steroid-induced osteopenia and fractures; a FRAX risk factor
• Anticoagulants (warfarin): usually contraindicate EMG
• Transdermal patches with aluminized backing (nicotine, nitroglycerin, scopolamine, clonidine): remove before MRI after notifying the provider
• Calcium and vitamin D supplements: see intake targets above; osteoporosis drugs are in Ch. 36

Related

• nsg210-hinkle-ch34-inflammatory-rheumatic-disorders (RA, SLE, gout)
• nsg210-hinkle-ch36-musculoskeletal-disorders (osteoporosis, osteoarthritis, arthroplasty)
• nsg210-hinkle-ch37-musculoskeletal-trauma (fractures, compartment syndrome, amputation)
• nsg210-week-08-rheumatic-diseases-lecture
• INDEX