Hip and knee conditions

Definitions

Acquired pediatric conditions

Conditions that develop after birth and do not have a link to genetic abnormalities.

Unlike congenital disorders, which are present at birth due to genetic or developmental causes, acquired conditions develop afterward from causes such as trauma, growth-related stress, or infection. This chapter covers common acquired conditions affecting the hip, knee, spine, and neuromuscular system, along with the physical therapy interventions used to manage each one.

PTA role reminder: For each condition below, the PTA carries out the plan of care established by the supervising PT - applying prescribed bracing, orthotics, or equipment; collecting data on the patient’s response; and communicating any changes to the PT - rather than evaluating, prescribing, or modifying the plan.

Legg-Calve-Perthes disease

Definitions

Legg-Calve-Perthes disease

A condition that occurs when there is a temporary interruption in blood flow to the femoral head, causing femoral head death and eventual collapse of the femoral joint. The cause of the interruption is idiopathic (unknown); repetitive minor trauma and blood-clotting abnormalities are proposed contributing factors.

Medical confirmation is performed through physical examination, MRI, and X-ray. The condition is most common in children under 10 years old.

Phases of Legg-Calve-Perthes disease

1. Necrosis: part of the femoral head has died
2. Fragmentation: the body attempts to clean up the broken pieces of bone from the area
3. Re-ossification: blood flow is restored to the femoral head, and the bone begins to regrow
4. Remodeling: new bone is now in place

Each phase can last from months to years, but it indicates the body has the potential to heal itself once temporary blood flow is restored.

Symptoms

• Antalgic gait
• Pain/stiffness in thigh/groin
• Leg length discrepancy
• Limitations in range of motion - abduction, flexion, and internal rotation

Physical therapy interventions for Legg-Calve-Perthes disease

• Activity modifications
• Bracing/splinting to keep the femoral head in contact with the acetabulum
• Strengthening and range of motion activities of the hip

Medical management of Legg-Calve-Perthes disease

• Use of anti-inflammatory medications
• Surgical containment (femoral or pelvic osteotomy) to keep the femoral head seated in the acetabulum - generally reserved for children over 6

Slipped capital femoral epiphysis (SCFE)

Definitions

Slipped capital femoral epiphysis (SCFE)

A condition in which the femoral head slips from the femoral plate at the growth plate.

Etiology can be due to hormonal changes during puberty, a growth spurt, obesity, weakening of the growth plate, and family history. The most common age of injury is between 10-16 years of age.

Symptoms

• Inability to bear weight on the extremity
• Pain in the groin/thigh
• Leg length discrepancy
• Limitations in range of motion - flexion, internal rotation, and abduction

Medical management for SCFE

Surgery is indicated once confirmed through physical examination and X-ray imaging. Delay in intervention can cause serious damage such as avascular necrosis, arthritis, or deformity of the hip joint. Surgery entails the implementation of a metal screw to maintain the position of the femoral neck through the growth plate.

Physical therapy interventions for SCFE

Physical therapy interventions are dependent upon the surgeon’s protocol post-op and will gauge the progression of activities until return to full weight bearing. Increased pain, inability to tolerate the next weight-bearing stage, or new limping during progression should be reported to the supervising PT rather than advanced independently.

The following table compares Legg-Calve-Perthes disease and slipped capital femoral epiphysis by age, typical child, what happens in the hip, findings, and management.

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Feature	Legg-Calve-Perthes disease	Slipped capital femoral epiphysis
Typical age	Under 10 years, most often 4-8	10-16 years, around the pubertal growth spurt
Typical child	More often boys; often small for their age	More often boys; obesity is a major risk factor
What happens	Blood flow to the femoral head is interrupted, so part of the head dies and collapses	The femoral head slips at the growth plate
Findings	Groin or thigh pain, antalgic gait, leg length discrepancy, limited abduction, flexion, and internal rotation	The same, and the child may be unable to bear weight
Management	Containment: activity modification, bracing, ROM and strengthening; surgical containment in older children	Urgent: non-weight-bearing and surgical screw fixation; PT follows the surgeon’s post-op protocol

Osgood-Schlatter disease

Definitions

Osgood-Schlatter disease

A condition in which an individual experiences knee pain and swelling at the tibial tuberosity due to increased pulling by the quadriceps on the patellar tendon.

Common causes are repetitive movements, excessive growth during puberty, and participation in sports that require increased running and jumping. Age of onset is typically after age 12, during puberty. Confirmation of diagnosis is through physical examination and X-ray.

Symptoms

• Palpable swelling at the tibial tuberosity
• Pain at anterior knee
• Increased pain during running and jumping activities, with relief of pain during rest

Physical therapy interventions for Osgood-Schlatter disease

• Conservative care: activity modification (reducing high-impact running/jumping until pain improves), ice therapy, and over-the-counter pain relievers as directed by the plan of care
• Strengthening of lower extremity muscles to create an even pull of muscles
• Dynamic balance activities to mimic times of exacerbation
• Postural re-education when performing running, jumping activities