Musculoskeletal Diseases and Disorders

Chapter 15

Musculoskeletal System Bones

Long, short, flat, irregular Compact, spongy

Joints Bursae Muscles Tendons Ligaments

Musculoskeletal System

Two divisions:Axial skeletonAppendicular skeleton (inc. pelvic girdle)

Muscle types:Skeletal muscle (voluntary, striated)Smooth muscle (involuntary, non-striated)Cardiac muscle (involuntary, striated)

Disorders of Bone

Spinal deformities Herniated intervertebral discs Osteoporosis Osteomyelitis Paget’s Disease (osteitis deformans) Fractures

Spinal Deformities

LordosisAbnormal “inward” or anterior curvatureAccentuation of normal curve of lumbar spineFrequently gradual onsetAffects lumbar spineAlso called “swayback”

Spinal Deformities

KyphosisAbnormal “outward” curvature of the spineAccentuation of normal thoracic spine curvatureAlso called “humpback” or “roundback”Commonly due to pathological fractures of spine in

osteoporosis

Spinal Deformities

ScoliosisLateral (sideways) curvature of the spineMay go to left or rightMay involve some rotation of spinal columnMay be caused by discrepancy in leg lengthsSurgery possible if interferes with breathing or mobility

Spinal Deformities

EtiologiesPosture, leg length differences, congenital, epiphyseal

growth disturbance, trauma, tumors, infection, arthritis, TB, endocrine abn, aging

S/S: usually backache, fatigue, abnormal appearance or fitting of clothes

Treatment: PT, exercise, braces, surgery, pain relief

Herniated Intervertebral Discs Disc Anatomy

Annulus fibrosisNucleus pulposis

HerniationNucleus pulposis pushes through annulus into spinal

canal Rupture

Pieces of the disc are free in the spinal canal

Herniated Disc

S/S: Back painParesthesiasSciatica: inflammation of sciatic nerve, leg pain

Treatment:PT, exercise, pain relief meds, surgery (rarely), life

correctly

Osteoporosis

Metabolic disorder of bonesLess bone mineral (calcium) than normal

Over 10 million in US affectedPost-menopausal females most commonly

Bones are brittle, porous, easily brokenMore prone to pathological fracture

Osteoporosis

Etiology:Genetics, calcium intake & dietary, sedentary lifestyle,

estrogen, vit D, or adrenal deficiency, steroid use, alcoholism, etc

S/S: often asymptomatic until pathological fx. Treatment: calcium supplements, meds

(antiresorptive, restorative of lost bone, etc)

Osteomyelitis Acute or chronic bone infection Inflammation, edema, circulatory problems More common in children Etiology:

Trauma most commonly with bacterial invasion from the skin

Infection may also spread from adjacent tissues or blood supply

Osteomyelitis

Risk factors:Diabetes, orthopedic hardware, splenectomy & SSA,

hemodialysis, IV drug users S/S: may be asymptomatic for years Treatment:

Long-term antibiotics, sometimes surgical debridement

Paget’s Disease

Osteitis Deformans Chronic metabolic bone disease

High rate of bone turnover (reabsorption & deposition) Thicker but softer bone is the result Patients typically over 40 YOA One or many bones

Usually lower torse involve

Paget’s Disease

Etiology: Unknown S/S: graduation onset of swelling & pain Treatment:

PT, pain management, surgeryMedications (biphosphonates or calcitonin) Joint replacements

Fractures Closed/simple Open/compound Greenstick Displaced Comminuted Segmental Spiral Pathological

Fractures

Etiology: trauma or disease S/S: usually pain and swelling Treatment:

Rest, decreased useSplint, sling, castSurgery (ORIF, etc)

Joint Diseases

Osteoarthritis Rheumatoid Arthritis Gout (gouty arthritis)

Osteoarthritis

Most common form of arthritis Chronic inflammation causing degeneration and

new bone formation Weight-bearing joints most common

Knees, hips Common in older patients (over 55 YOA)

In over 70 YOA, females more frequently affected

Osteoarthritis Etiology:

Mechanical, chemical, genetic, autoimmune, metabolic Aging seems to be important

S/S: May be asymptomatic indefinitely Pain, swelling, sometimes erythema, limitation of motion

Treatment: Anti-inflammatories, PT, exercise, surgical

Rheumatoid Arthritis

Chronic, systemic, polyarticular inflammatioy diseaseDestruction (erosion) of bone & cartilageCauses ankylosis (fibrous fusion of joints, immobile)

Exacerbations and remissions unpredictable Affects mostly females

Increasing risk with advancing age

Rheumatoid Arthritis (RA) Etiology: autoimmune, genetics S/S: symmetric pain, swelling of hands & fingers,

also other LE joints, systemic (fever, fatigue, wt. Loss)

Dx testing: Rheumatoid factor blood test Treatment:

Antiinflammatories, PT, antimetabolites, antirheumatic drugs

Gout Gouty arthritis Chronic uric acid metabolism disorder

Uric acid crystals deposited in joints Tophi formation (urate compounds) around joints

Acute, severe episodes of arthritis Mostly male patients Other associated problems:

Kidney stones, renal failure, hyperuricemia

Gout Etiology:

Metabolic, renal, some genetics S/S:

Severe signs & symptoms of inflammationBig toe is classical site

Treatment:Pain relief, antiinflammatories, colchicine, diet low in

purines, alopurinol

Muscles & Connective Tissue Diseases

Sprains & strains Bursitis & tendonitis Carpal Tunnel Syndrome Myasthenia Gravis (MG) Polymyositis Systemic Lupus Erythematosus (SLE) Duchenne’s Muscular Dystrophy

Sprains & Strains

SprainLigamentous tearing/stretching after a tortion injury

StrainTearing/stretching of tendon or muscle

Etiology: trauma or overuse S/S: localized pain, swelling, limitation of motion Treatment: supportive, pain relief

Bursitis & Tendonitis Bursitis

Inflammation of fluid-filled bursae near joints Shoulder, hip, elbow, knee

Tendonitis Inflammation of tendon or tendon-muscle attachementShoulder, wrist, Achilles, hamstring

Etiology: trauma, excessive use, other diseases S/S: pain, swelling, LOM, fluid accumulation

Bursitis & Tendonitis

TreatmentVaries with anatomic location & degree of disabilityAnti-inflammatories & pain relievers, splinting,

exercise, orthotics, steroid injections, PT

Carpal Tunnel Syndrome

Compression of median nerve within the carpal tunnel of the wrist

Common syndrome with repetitive use work Involves pain, sensory & motor symptoms Etiology: edema within the carpal tunnel, causing

inflammation of the nerve & other structures there

Carpal Tunnel Syndrome

S/S:Wrist pain, burning or tingling paresthesias, numbnessWeakness of hand graspTinel’s sign

Treatment:Wrist immobilization, anti-inflammatoriesRarely surgery

Myasthenia Gravis

Rare, autoimmune disorder of the neuromuscular junction

Antibodies against the acetylcholine receptors (post-synaptic)

Chronic, progressive disease causing sporadic weakness of the skeletal muscles

Most common in females, ages 20-40 YOA

Myasthenia Gravis (MG)

Reduced muscle strength & longer recovery time with repeated useSymptoms late in the dayBulbar (eye & facial) muscles involved firstFacial expression, drooping lids, etc.

Thymomas in 15% MG patients75% have some thymic abnormality (hyperplasia)

MG Diagnostic testing:

Tensilon test (edrophonium challenge will increase muscle strength)

Treatment: Oral anticholinergic meds (pyridostigmine,

neostigmine), immune suppressives, cholinesterase inhibitors like edrophonium

Prognosis: normal life expectancy in modern times

Polymyositis

Chronic, idiopathic inflammatory disease of connective tissues and muscles

Exacerbations & remissions May have skin involvement (dermatomyositis) females more than males Bimodal peak of onset: 5-15 YOA & 50-70YOA

Polymyositis S/S: sudden or slow weakness of muscle group over

weeks to months Often have trouble arising from sitting or raising arms above

head, also voice changes Fever, fatigue, weight loss Skin: lilac-colored rash of eyelids, nose and face

Dx via EMG & muscle biopsy Treatment: immune suppressive

Systemic Lupus Erythematosus

Lupus or SLE Multisystem, autoimmune, inflammatory disease

due to antibodies against cell nuclei Females outnumber male patients ( 9 to 1) Genetics may also be involved Arthralgias are first complaint in most patients

SLE

Organ involvement:Skin, renal, CNS, GI, blood, musculoskeletal, CV,

pulmonary, vascular endothelium (Raynaud’s) Four criteria at any time:

Malar rash or discoid rash, photosensitivity, arthritis, renal disease, neuro, skin, hematologic, or immune disorders, +ANA blood test

SLE

Treatment:Anti-inflammatories, pain relief, immune suppressives

Duchenne’s Muscular Dystrophy Inherited, x-linked, recessive disorder

Seen only in malesOccasionally no family history

Rapidly progressive wasting of skeletal musclesFirst in lower extremity & pelvis, then generalizes

Usually appears by 6 YOA Cause of death: respiratory insufficiency usually

by 25 YOA

Duchenne’s Muscular Dystrophy

At first muscles appear largerDue to fat and CT infiltration

Then atrophy (wasting, decrease in size) Then scarring & contractures Cardiomyopathy present in almost all cases

Neoplasms

Osteogenic sarcoma Chondrosarcoma Malignant giant-cell tumor

Osteogenic Sarcoma

Most common bone cancer 3rd most common cancer in adolescence Slightly more males Risk factors: radiation therapy, genetics Treatment: surgical, but mets later in 80% Most in long bones

Femur, tibia, humerus (in that order)

Chondrosarcoma

2nd most frequent primary bone cancer (25%) Malignant tumor of cartilage Mostly over 40 YOA (mostly geriatric) Affects pelvis, femur, humerus, ribs

Giant Cell Tumor

Multinucleated cells 5-10% of all giant cell tumors are malignant Recurs locally about 50% of the time Only 4-5% of all bone tumors Mostly long bones Mostly 20-40YOA Relatively good Px after tumor excision