(22) Musculoskeletal Lecture 3: Pediatric Disorders; Muscular Dystrophy, Developmental Hip Dysplasia, Con

Pediatric Musculoskeletal Disorders

Overview of Disorders Discussed:

• Muscular Dystrophy: A group of genetic diseases characterized by progressive weakness and degeneration of skeletal muscles. Duchenne Muscular Dystrophy (DMD) is the most common form, primarily affecting boys.

• Developmental Hip Dysplasia (DDH): A condition in which the hip joint does not properly fit into the hip socket, leading to potential dislocation. It can range from mild cases to severe dislocation and is more prevalent in females.

• Congenital Talipes Equinovarus (Clubfoot): A congenital deformity involving the foot being twisted out of shape or position. It may occur in one foot (unilateral) or both feet (bilateral).

Key Areas to Cover:

• Etiology: Genetic factors, environmental influences, and familial trends play a role in the development of these conditions.

• Pathophysiology: Each disorder has distinct mechanisms, such as the genetic mutation in DMD leading to a lack of dystrophin protein, which is crucial for muscle membrane stability. In DDH, misalignment of the femoral head within the acetabulum leads to joint instability.

• Types: Different subtypes of muscular dystrophies exist, while DDH can be classified into teratologic, positional, or idiopathic forms.

• Clinical Manifestations: Symptoms vary widely; for DMD, common signs include gait changes and frequent falls. DDH may present as uneven leg lengths or limited hip movement.

• Diagnostic Tests: Diagnosis can include genetic testing, X-rays, and physical assessments such as the Barlow and Ortolani maneuvers for DDH.

• Medical Management: Options include braces or surgical interventions for DDH, supportive therapies, and medications for muscular dystrophies aimed at improving quality of life.

• Nursing Interventions: Care approaches often focus on early detection, patient education, emotional support, and teamwork with families.

• Patient Teaching: Teaching families about the importance of early intervention and management strategies to improve outcomes is vital.

• Prognosis: Early diagnosis generally leads to better management outcomes. Muscular dystrophies like DMD have a poorer long-term prognosis, often impacting life expectancy and quality of life significantly.

Characteristics of Musculoskeletal System in Children

• Bone Structure Differences:

  • Growth plates (epiphyses) are present and continue to allow for bone growth until skeletal maturity (approximately 18-25 years).

  • Children have a higher cartilage content, providing increased flexibility and decreased fracture risk compared to adults.

  • Children heal faster due to thicker periosteum, which aids in bone remodeling.

  • Lower bone density leads to less mineralization and increased porosity, raising the risk for deformities.

• Muscle Development:

  • Muscle fibers increase in size with growth, while the number remains constant until maturity.

  • Higher elasticity in muscle tissues allows for greater resistance to strains and tears compared to adults, although muscle mass is less.

  • Children recover from muscle exertion more quickly, which contributes to a higher capacity for repeated activities.

• Common Musculoskeletal Issues:

  • Often arise from genetic predisposition, rapid growth phases, or increased physical activity.

  • Conditions such as Osgood-Schlatter disease and Sever's disease are commonly seen in active children and may be temporary as children grow.

  • Thorough assessments are imperative to ascertain musculoskeletal health in pediatric patients, noting that many conditions may resolve spontaneously with time.

Assessment Techniques:

• Perform comprehensive head-to-toe assessments, including observing gait, muscle tone, and any signs of discomfort.

• Palpate muscles and bones in areas exhibiting pain, swelling, or abnormal alignment.

• Evaluate range of motion in affected areas, especially when assessing for DDH or other mobility issues.

Developmental Dysplasia of the Hip (DDH)

• Definition: DDH involves malformation of the hip joint, where the femoral head is improperly positioned within the acetabulum, leading to variable degrees of dislocation, from mild instability to complete dislocation.

• Increased Occurrence: Notable in females, especially those with a family history of hip dysplasia, as well as in cases associated with breech deliveries and conditions like spina bifida.

• Causes: Tight swaddling, abnormal uterine positioning, and maternal hormones may increase the risk by affecting the hip's stability.

• Signs and Symptoms: Indicators may include a shortened femur on the affected side, asymmetrical thigh or gluteal folds, and in walking children, a noticeable limp or waddling gait.

• Diagnosis: Early diagnosis is vital and includes physical assessments. The Barlow and Ortolani maneuvers are key techniques, supported by imaging when necessary (ultrasound or X-ray).

• Treatment: Timely intervention is essential; less than six months old, a Pavlik harness may be utilized, while older children may require hip spica casts or surgical procedures if conservative measures fail.

• Nursing Role: Nurses play a crucial role in recognizing symptoms, providing education to families, ensuring the proper use of assistive devices, and monitoring for potential complications.

Congenital Talipes Equinovarus (Clubfoot)

• Epidemiology: The most common congenital foot deformity, occurring in approximately 1 in every 1000 live births, with a higher incidence in males.

• Condition Description: The foot appears to be twisted, with the toes pointing down and inward, possibly affecting one or both feet. Muscles, tendons, and ligaments in the affected area may be shorter or weaker.

• Diagnosis: Physical examination effectively identifies the deformity; confirmation may involve X-ray imaging to assess severity.

• Management: Early intervention is key for better outcomes, which may include initial casting and manipulation followed by stretching exercises and corrective measures like orthotic shoes. Surgical correction (tenotomy) might be needed for persistent deformities.

• Nursing Interventions: Nurses provide comprehensive support, educate families about the treatment process, ensure proper casting techniques, and monitor for signs of skin irritation or circulation issues.

Muscular Dystrophy (Focusing on Duchenne Muscular Dystrophy - DMD)

• Overview: DMD is the predominant type of muscular dystrophy, usually manifesting in early childhood around ages 2-3, with gradual progression leading to significant physical disability.

• Etiology: DMD is a hereditary condition caused by mutations in the dystrophin gene found on the X chromosome, which is essential for muscle cell integrity.

• Symptoms: It presents with characteristic signs such as a waddling gait, frequent falls, and muscle weakness, most notably in the pelvic and leg muscles. Calf muscles may appear enlarged (pseudohypertrophy), falsely suggesting strength.

• Diagnosis: Blood tests reveal elevated levels of creatine kinase (CK), an enzyme released during muscle breakdown. Confirmatory genetic testing for dystrophin mutations solidifies the diagnosis.

• Management Goals: While there is no cure, goals focus on maximizing mobility and independence through physical therapy, respiratory support, and preventive measures against complications.

• Nursing Involvement: Nurses provide ongoing supportive care, facilitate family education, discuss coping strategies, and prepare families for potential progression related to respiratory and cardiac challenges that impact longevity (life expectancy is often reduced to around 20 years).

Final Remarks

• Key Points Recap: Early recognition and intervention of pediatric musculoskeletal disorders are vital for optimizing treatment outcomes and quality of life.

• Engagement with Families: Active involvement of families in care plans and education significantly enhances adherence to treatment protocols and fosters confidence in managing their child's condition.

• Q&A Invitation: Open the floor for questions and case discussions to clarify concepts and increasingly engage with current learning.