The Musculoskeletal System

Musculoskeletal System: Bones

• Functions of the Musculoskeletal System:     * Support: Providing structural framework for the body.     * Assist with movement: Working in conjunction with muscles to facilitate locomotion.     * Protection: Shielding internal organs from injury (noted as "protect alot" in supplemental notes).     * Hematopoiesis: The production of blood cells within the bone marrow.     * Storage: Acts as a reservoir for essential minerals, specifically calcium and phosphorous.

• Gross Structure of Bone:     * Diaphysis: Defined as the main staff or shaft of the bone.     * Epiphysis: The end portions of a long bone.     * Metaphysis: The flared area of the bone located between the diaphysis and epiphysis.     * Epiphyseal plate: Known as the growth zone or growth plate.

Musculoskeletal System: Joints and Muscles

• Joints (Articulations):     * Definition: The points where bones meet; they provide stabilization and permit a variety of body movements.     * Classification by Degree of Movement:         * Synarthroses: Immovable joints, such as those found in the skull.         * Amphiarthroses: Slightly movable joints, such as the vertebrae.         * Diarthroses: Freely movable joints, such as the shoulder.

• Muscles:     * Functions: Provides shape to the body, protects bones, maintains posture, and facilitates movement through contraction.     * Types of Muscle Tissue:         * Cardiac: Involuntary muscle found exclusively in the heart; responsible for propelling blood through the circulatory system.         * Smooth: Involuntary muscle found in the walls of hollow structures.         * Skeletal (striated): Voluntary muscle responsible for body movement.

Growth, Metabolism, and Chemical Regulation

• Calcium and Phosphorous: These minerals maintain an inverse relationship within the body.

• Vitamin D: Required for the efficient absorption of Calcium ($Ca$) from the intestines.

• Calcitonin:     * Secreted when blood Calcium levels are too high.     * Functions: Decreases bone resorption (the breakdown of bone) and increases the renal excretion of calcium.

• Parathyroid Hormone (PTH):     * Secreted when blood Calcium levels are too low.     * Functions: Increases bone resorption to release Calcium into the blood and decreases the renal excretion of Calcium.

• Growth Hormone: Secreted from the pituitary gland; it is the primary determinant of bone growth and size/height.

Nursing Assessment and Clinical Interventions

• Health History: Focuses on the presenting problem and the patient's lifestyle.

• Physical Examination:     * Inspection: Observing for posture, gait, movement, and limb length.     * Palpation: Checking for tenderness or abnormalities.     * Range of Motion (ROM): Assessing abduction, adduction, flexion, and extension. Includes evaluation for passive muscle pain or weakness.

• Nursing Interventions (RICE Protocol): Used to treat injuries to decrease edema, pain, and mobilize fluid removal from the injured area.     * Rest: Stop activity immediately.     * Ice: Apply to the injured area ($20 - 30\,\text{min}$).     * Compress: Use compression to manage swelling.     * Elevation: Lift the injured area above the level of the heart.

Serology and Diagnostic Studies

• Alkaline Phosphatase: Elevated levels are an indicator of bone damage.

• Muscle Enzymes: Creatine Kinase (CK) is specific for skeletal muscle; elevation indicates muscle damage.

• C-reactive protein (CRP): A protein produced by the liver in response to tissue injury or inflammation.

• CBC (Complete Blood Count): Leukocytosis (elevated WBC count) is primarily seen with bacterial infections, such as a "septic joint."

• Calcium Monitoring: Bone is the primary storage organ for Calcium. Low levels may be seen in kidney disease, while high levels may occur in hyperthyroid conditions or cancer.

• Diagnostic Imaging:     * Basic X-rays: Standard imaging for fractures and bone structure.     * CT Scans: Uses an X-ray beam and computer to provide a $3\text{D}$ picture; can be performed with or without contrast medium.     * MRI: Utilizes radio waves and magnetic fields to view soft tissue and detect soft tissue abnormalities.     * Bone Scans: Involves the injection of a radioisotope to detect skeletal problems (e.g., osteoporosis, avascular necrosis). Post-procedure, patients must drink fluids to rid the body of the dye.

Interventional Studies and Procedures

• Biopsy (Muscle or Bone):     * Can be open or closed.     * Major risk: Bleeding post-procedure.     * Intervention: Apply a compression dressing.

• Arthrocentesis:     * Involves the aspiration of synovial fluid for analysis using a local anesthetic.     * Nursing focus: Assess CMTS (Color, Motion, Temperature, Sensation).

• Arthroscopy:     * Insertion of an arthroscope into a joint for interior visualization or joint repair (e.g., meniscus tears).     * Performed under local or general anesthesia.     * Nursing focus: Cover the wound post-op and monitor CMTS.

Strains, Sprains, and Genetic Bone Disorders

• Strains: Excessive stretching of a muscle, often involving the tendon. Often occurs in the back or large muscle groups.     * Classified as mild, moderate, or severe.     * Severe strains may require surgery.

• Sprains: Injury to the ligaments surrounding a joint, usually caused by wrenching or twisting (common in ankles, wrists, and knees).     * Classified as mild, moderate, or severe.     * More likely to require immobilization.

• Manifestations for both Strains and Sprains: Pain, edema, decreased function, and bruising.

• Osteogenesis Imperfecta:     * A genetic disorder categorized into Types $1 - 4$.     * Symptoms: Frequent fractures, short stature, and spinal deformities.

Bone Tumors: Types, Manifestations, and Care

• Classification: Malignant vs. Benign; Primary vs. Secondary (metastatic) tumors.

• Osteosarcoma: An aggressive malignant tumor of the metaphysis, commonly affecting the femur, tibias, and humerus. Often necessitates amputation.

• Ewing’s Sarcoma: A malignant tumor usually found in the medullary cavity of long bones (arms, legs, pelvis).

• Clinical Considerations: Both typically occur in children and young adults.     * Manifestations: Pain, swelling, and elevated WBC count.     * Diagnosis: X-ray, CT, MRI, Bone biopsy, and Serum alkaline phosphatase.     * Treatment: Surgery and Chemotherapy.     * Nursing Care: Administering chemo and meds, ensuring safety (fracture risk), pain management, and addressing anticipatory grieving and anxiety.

Muscular Dystrophy

• Definition: A group of genetic diseases characterized by progressive symmetric wasting of skeletal muscles without neurologic involvement.

• Duchenne Type: The most common form of the disorder.     * Primarily affects boys with an onset before age $5$.     * Sign: Gower’s sign (using hands to "walk up" the legs to stand).     * Clinical progression: Frequent falls, waddling gait, and typically terminal by the $20\text{s}$.

• Diagnosis: Muscle biopsy (confirms diagnosis), EMG, and elevated CK-mm levels.

• Management: No known cure; focus on maintaining optimal functioning, evaluating abilities, and supporting the family/patient.

Disorders of the Spine: Scoliosis

• Structural Scoliosis:     * Characterized by an "S-shaped" curve of the spine.     * Usually idiopathic and involves structural changes that do not disappear with position changes.     * Commonly seen in adolescent girls.     * Diagnosis: X-ray to reveal the degree of the curve.

• Management:     * Monitoring the degree of the curve; curves of $25^{\circ}$ or more require intervention.     * Bracing: Worn at night or for up to $23\,\text{hours}$ a day to stop curve progression.     * Surgical Intervention: Spinal fusion for severe cases.

• Nursing Interventions: Address compliance issues, maintain skin integrity, and provide diversional activities.

Amputation: Indications and Postoperative Care

• Clinical Indications: Circulatory impairment from Peripheral Vascular Disease (PVD) or peripheral ulcers, traumatic injuries, battle injuries, thermal injuries, tumors, infection (osteomyelitis), and congenital limb disorders.

• Postoperative Management:     * Assess for Post-Traumatic Stress Disorder (PTSD).     * Manage "phantom pain": The feeling that the limb is still there due to nerve endings.     * Monitor Vital Signs (VS) and assess dressings for hemorrhage.

• Prevention of Flexion Contractures:     * Do not sit in a chair for more than $1\,\text{hour}$ with hips flexed.     * Do not place pillows under the surgical extremity.     * Position the patient prone (on their abdomen) for $30\,\text{minutes}$, $3-4\times/\text{day}$.

• Compression Bandage: Initially worn at all times (except during PT and bathing) to foster shaping and molding for a prosthesis.

Fractures: Classification and Manifestations

• Classification:     * Trauma vs. Pathological: Pathological fractures are often due to conditions like osteoporosis.     * Open vs. Closed: Open fractures involve the bone being exposed through the skin.

• Manifestations: Pain, decreased function, inability to bear weight, bone deformity, bruising, swelling, and muscle spasms.

• Intervention: Requires reduction (realignment) and immobilization.

Fracture Management: Reduction, Fixation, and Traction

• Reduction and Fixation:     * Closed Reduction: Non-surgical, manual realignment; patient may be sedated or given meds to sleep through it.     * Open Reduction: Surgical realignment via incision.     * Internal Fixation: Use of hardware (wires, pins, screws, nails) inserted into the bone.     * External Fixation: Use of external rods with pins inserted into the bone from the outside.

• Traction:     * Application of a pulling force to reduce spasms, immobilize the area, reduce the fracture, or treat a pathologic condition.     * Buck’s Traction: A specific type of traction most often used for hip or femur fractures.

Fracture Management: Casting and Compartment Syndrome

• Casting:     * Provides temporary circumferential immobilization.     * Cast Care: Apply ice for swelling, dry with a hair dryer (if plaster), elevate above the heart. Do not get wet (unless fiberglass), remove padding, or insert objects.

• Compartment Syndrome:     * Occurs when swelling increases pressure within a limited space (lower extremity is common), compromising neurovascular function.     * The 6 P's (Manifestations): Pain (out of proportion to injury), Pressure (increased), Paresthesia (numbness/tingling), Pallor, Paralysis (loss of function), and Pulselessness.     * Treatment: Do NOT elevate above the heart and do NOT use ice (causes vasoconstriction). Surgical intervention is a fasciotomy (surgical decompression) to allow the compartment to "breathe."

Osteomyelitis and the Fracture Healing Process

• Osteomyelitis:     * Severe infection of the bone, bone marrow, and soft tissue, usually caused by Staphylococcus aureus.     * Leads to necrosis and bone death.     * Manifestations: Fever, night sweats, chills, bone pain, swelling, and warmth.     * Treatment: Long-term IV and PO antibiotics (e.g., Vancomyocen for $6\,\text{weeks}$) and Hyperbaric oxygen ($100{\%}$ oxygen).

• Fracture Healing Stages:     1. Hematoma     2. Granulation tissue     3. Callus formation     4. Ossification     5. Consolidation     6. Remodeling

• Healing Time Frames:     * Neonate: $2 - 3\,\text{weeks}$.     * Early Childhood: $4\,\text{weeks}$.     * Adolescence: $8 - 10\,\text{weeks}$.     * Adults & Elderly: Generally longer, significantly impacted by comorbidities.

Hip Fractures: Specialized Care and Complications

• Occurrence: Extremely common in older adults; $95{\%}$ result from falls.

• Clinical Manifestations: External rotation, muscle spasms, shortening of the affected extremity, and severe pain/tenderness.

• Management:     * Pre-op: Analgesics or muscle relaxants; comfortable positioning.     * Post-op: Monitor VS, I&O, and Neurovascular status (Color, Temp, Cap refill, Pulses, Sensation, Motor, Pain/CTMS).     * Recovery Rules: Do not cross legs at the knees. Use an elevated toilet seat. Use an abductor pillow between the legs for the first $6\,\text{weeks}$ post-surgery.

VTE Prevention and Pharmacological Monitoring

• Intraoperative: keeping BP lower to manage risks.

• Anticoagulation Medications: Warfarin (Coumadin), LMWH (Lovenox), ASA (Aspirin), Factor Xa inhibitors (Eliquis).

• Mechanical Prevention: Early ambulation and Sequential Compression Devices (SCDs).

• Lab Monitoring for Coumadin (Warfarin):     * Prothrombin Time (PT): Baseline is roughly $13$.     * Therapeutic Goal: $1.5 - 2.0 \times$ the baseline.     * Calculation Example:         * $13 \times 1.5 = 19.5$         * $13 \times 2.0 = 26$         * Therapeutic Range: $19.5 - 26$

• International Normalized Ratio (INR): Target therapeutic range is typically $2.5$, or between $2 - 3$.

• Note on Heparin: Monitored via pTT labs; the antidote is Protamine Sulfate. For Coumadin, the antidote is Vitamin K.