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Introduction
1. Cardiovascular system
2. Pulmonary system
3. Neuromuscular system
4. Pediatrics
4.1 Pediatric foundations
4.2 Congenital disorders
4.2.1 Congenital neurological and genetic disorders
4.2.2 Congenital musculoskeletal disorders
4.3 Developmental and acquired disorders
5. Musculoskeletal system
6. Other systems
7. Non-systems
Wrapping up
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4.2.2 Congenital musculoskeletal disorders
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4. Pediatrics
4.2. Congenital disorders
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Congenital musculoskeletal disorders

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The following congenital disorders primarily affect the bones, joints, and connective tissue.

Developmental dysplasia of the hip (DDH)

Definitions
Developmental dysplasia of the hip (DDH)
A condition, usually present at birth but sometimes developing later in infancy, in which the hip joint develops abnormally, resulting in an acetabulum too shallow to properly fit the femoral head. The abnormal fit allows for recurrent dislocation, which, if untreated, can impair gait and later lead to early hip degeneration.

Factors that contribute to the development of DDH include first pregnancy, breech birth, swaddling too tightly with the legs extended, increased infant size, female sex, and family history.

Common symptoms

  • Leg length discrepancy (affected leg is shorter than the unaffected)
  • Increased folds in the skin of the thigh/buttocks of the affected extremity
  • Limited hip abduction on the affected side (the main sign after about 3 months of age, once Ortolani/Barlow are no longer positive)
  • Increased popping noted when moving the affected leg
    • Ortolani test
      • Abduction of the flexed hip reduces a dislocated femoral head back into the acetabulum, producing a palpable clunk
    • Barlow test
      • Adduction of the flexed hip provokes (dislocates) an unstable hip, producing a palpable clunk
Congenital hip dysplasia
Congenital hip dysplasia
Achievable
Ortolani test
Ortolani test
Achievable

Physical therapy interventions for DDH

  • Education provided to the family for the appropriate positioning of the infant to reduce hip dislocation occurrence
  • Gentle range of motion activities that do not cause dislocation
  • Wearing of Pavlik harness
    • The Pavlik harness is a soft splint used to allow for consistent contact between the acetabulum and the femoral head
      • Positioned in abduction of legs, hip flexion, and knee flexion through a series of straps to keep the infant in this position
    • Used for infants 6 months or younger, with a goal of 24-hour wear for the first 6 weeks, progressing to nighttime-only wear for the following 6 weeks
      • The parents must learn how to care for the baby fully during the period of continuous wear
      • Change from wearing 24 hours a day to only at night is determined by an orthopedic physician via x-ray and ultrasound
      • Developmental delay may occur in an infant due to constant positioning, as mentioned above, with decreased ability to move out of position
Pavlik harness
Pavlik harness
Achievable

Example: Pavlik harness adherence

During the 24-hour wear phase, a parent asks the PTA to remove the harness for bathing.

Answer: The PTA reinforces the current wear schedule. Changing it is a physician decision based on follow-up imaging, not something the PTA or family adjusts on their own.

Clubfoot (talipes equinovarus)

Definitions
Clubfoot (talipes equinovarus)
A congenital deformity in which the foot is fixed in plantarflexion (equinus), hindfoot inversion (varus), forefoot adduction, and a high arch (cavus), with tight posterior and medial soft tissues including the Achilles tendon. Etiology is unknown, but it may be related to imbalanced development of the tendons and muscles of the foot during pregnancy, or to spina bifida.

Phases of intervention

  • Phase 1: serial casting
    • Clubfoot is stretched/manipulated to improve the range of motion, and then a hard cast is set in place over the affected extremity
      • The hard cast is removed, and stretching occurs again, with a new cast put in place with the new range of motion that has been achieved
      • The goal is to wear the hard cast until normal alignment is achieved - can take 4-10 weeks to achieve normal alignment
      • Most infants then undergo a percutaneous Achilles tenotomy to correct the remaining equinus before the final cast
Serial casting for clubfoot
Serial casting for clubfoot
Achievable
  • Phase 2: bracing
    • Once serial casting is complete (normal alignment is achieved), bracing is put in place to aid in maintaining the normal alignment of the foot
      • A foot-abduction brace (boots on a bar) is worn about 23 hours a day for roughly 3 months, then during nighttime sleep and naps until about age 4
      • Non-adherence to bracing is the leading cause of relapse

Surgical intervention may be necessary depending on the severity of the deformity and the inability to change Achilles tendon length through conservative measures.

Metatarsus adductus is a common foot deformity usually noted at birth in which the forefoot turns inward.

Physical therapy interventions for clubfoot

Within the PT’s plan of care, the PTA may assist with stretching between casts, teach families how to put on the brace and check the skin, monitor motor milestones, and report skin breakdown, poor brace tolerance, or loss of correction to the supervising PT. Choosing or changing the brace is a PT or physician decision.

Osteogenesis imperfecta

Definitions
Osteogenesis imperfecta
A group of genetic disorders that impacts an individual’s ability to produce strong, healthy bones (most often a defect in the amount or structure of type I collagen, the most abundant protein in bone), increasing the risk of bone fractures with minimal impact.

Symptoms of osteogenesis imperfecta

  • Short stature
  • Joint laxity
  • Frequent fractures
  • Bone deformities
  • Muscle weakness
  • Hearing loss
  • Dental problems
  • Blue or gray-blue sclerae (a classic sign)

There are varying degrees of severity of osteogenesis imperfecta, ranging from mild symptoms that persist throughout life to severe symptoms in which the newborn dies within weeks of birth.

Rickets, which is usually not genetic (inherited forms such as X-linked hypophosphatemic rickets are rare), also causes soft, weak bones in children, usually because they do not get enough vitamin D, which helps growing bones absorb calcium and phosphorus. Symptoms include bone pain or tenderness, impaired growth, and deformities of the bones and teeth.

Physical therapy interventions for osteogenesis imperfecta

  • Support the trunk and limbs with open hands; never lift by the ankles or pull on a limb
  • Avoid twisting/torsional forces; use active or gentle assisted ROM only, never forceful stretching
  • Aquatic therapy allows safe strengthening with reduced joint stress
  • Education on swaddling, positioning, handling, and fall-prevention strategies as the child progresses through developmental milestones

Arthrogryposis multiplex congenita (AMC)

Definitions
Arthrogryposis multiplex congenita (AMC)
A rare, non-progressive congenital condition characterized by multiple joint contractures found in at least two different body areas, present at birth and resulting from limited fetal movement in the womb (fetal akinesia).

The condition is not a single disease but a clinical finding that may have several underlying causes, primarily involving the neuromuscular system. When a fetus does not move enough in utero, the joints do not develop normally and soft tissues such as muscles and tendons can become contracted.

Clinical presentation

  • Multiple joint contractures at birth (e.g., clubfoot, extended knees, flexed wrists, thumb-in-palm deformity)
  • Muscle hypoplasia or replacement of muscle tissue with fibrous or fatty tissue
  • Thin, atrophic limbs
  • No progressive neurological decline
  • Normal cognitive function in most cases

Medical and physical therapy management

  • Physical therapy: early passive range of motion and daily stretching to prevent worsening contractures, positioning and serial casting to correct deformities, strengthening of available muscle groups, and mobility/gait training with assistive devices (walkers, wheelchairs, KAFOs) as needed
  • Orthotic management: AFOs or KAFOs for ambulation, hand splints to improve function, and spinal orthoses if scoliosis develops
  • Surgical management: surgery (soft-tissue releases, tendon transfers, osteotomies) may follow if conservative care fails; post-op PT follows the surgeon’s protocol

AMC-related clubfoot is stiffer, more prone to relapse, and more often needs surgery than idiopathic clubfoot.

PTA role across these conditions: the PTA follows the PT’s plan - assisting with stretching, brace/orthosis wear, positioning, and ROM - rather than choosing orthoses or progressing casting independently. Report promptly: skin breakdown or loss of active knee kicking in a Pavlik harness (possible femoral nerve palsy), forced/excessive hip abduction (risk of avascular necrosis), and in OI, new pain, swelling, deformity, or refusal to move a limb (possible fracture).

Condition Core problem Key sign Main precaution
DDH Shallow acetabulum, hip instability Palpable clunk or limited abduction Avoid dislocating positions; follow Pavlik schedule
Idiopathic clubfoot Soft-tissue contracture Foot fixed down and inward at birth Maintain casting/bracing schedule
Osteogenesis imperfecta Defective bone collagen Frequent fractures, blue sclerae Gentle handling; no forceful ROM
AMC Limited fetal movement Multiple fixed contractures at birth Early, consistent stretching

Developmental dysplasia of the hip (DDH)

  • Shallow acetabulum allows femoral head to dislocate; risk factors: breech birth, first pregnancy, tight swaddling, female sex, family history
  • Key signs: leg length discrepancy, asymmetric thigh folds, limited hip abduction (>3 months); Ortolani (abduction reduces hip, clunk) and Barlow (adduction dislocates hip, clunk) tests
  • Treatment: Pavlik harness (hip flexion/abduction, knee flexion) worn 24hrs/day initially, then nights only—schedule changes only by physician via imaging, not PTA/family

Clubfoot (talipes equinovarus)

  • Foot fixed in plantarflexion, hindfoot varus, forefoot adduction, high arch; tight Achilles and medial tissues
  • Phase 1: serial casting (4-10 weeks) with repeated stretch/cast cycles, often followed by percutaneous Achilles tenotomy
  • Phase 2: foot-abduction brace (boots on bar), 23hrs/day initially tapering to nights until ~age 4; non-adherence = leading cause of relapse
  • PTA assists with stretching, brace education, skin checks; reports poor tolerance/loss of correction; brace changes are PT/physician decision

Osteogenesis imperfecta

  • Genetic disorders, most often a type I collagen defect, cause fragile bones, frequent fractures with minimal trauma
  • Symptoms: short stature, joint laxity, bone deformities, hearing loss, blue/gray-blue sclerae (classic sign)
  • PT care: support limbs with open hands (never lift by ankles/pull limbs), avoid twisting/forceful ROM, use aquatic therapy, educate on safe handling/positioning

Arthrogryposis multiplex congenita (AMC)

  • Non-progressive condition from limited fetal movement (fetal akinesia), causing multiple joint contractures in ≥2 body areas at birth
  • Features: muscle hypoplasia, thin atrophic limbs, normal cognition in most cases, no neurological decline
  • Management: early PT (passive ROM, stretching, serial casting, strengthening), orthotics (AFOs/KAFOs, hand splints), surgery if conservative care fails
  • AMC-related clubfoot is stiffer, more relapse-prone, more often needs surgery than idiopathic clubfoot

Cross-condition PTA role and precautions

  • PTA follows PT’s plan for stretching, bracing, positioning—does not independently choose/progress orthoses or casting
  • Report immediately: skin breakdown, loss of knee kicking in Pavlik (femoral nerve palsy risk), forced hip abduction (avascular necrosis risk), new pain/swelling/refusal to move in OI (possible fracture)

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Congenital musculoskeletal disorders

The following congenital disorders primarily affect the bones, joints, and connective tissue.

Developmental dysplasia of the hip (DDH)

Definitions
Developmental dysplasia of the hip (DDH)
A condition, usually present at birth but sometimes developing later in infancy, in which the hip joint develops abnormally, resulting in an acetabulum too shallow to properly fit the femoral head. The abnormal fit allows for recurrent dislocation, which, if untreated, can impair gait and later lead to early hip degeneration.

Factors that contribute to the development of DDH include first pregnancy, breech birth, swaddling too tightly with the legs extended, increased infant size, female sex, and family history.

Common symptoms

  • Leg length discrepancy (affected leg is shorter than the unaffected)
  • Increased folds in the skin of the thigh/buttocks of the affected extremity
  • Limited hip abduction on the affected side (the main sign after about 3 months of age, once Ortolani/Barlow are no longer positive)
  • Increased popping noted when moving the affected leg
    • Ortolani test
      • Abduction of the flexed hip reduces a dislocated femoral head back into the acetabulum, producing a palpable clunk
    • Barlow test
      • Adduction of the flexed hip provokes (dislocates) an unstable hip, producing a palpable clunk

Physical therapy interventions for DDH

  • Education provided to the family for the appropriate positioning of the infant to reduce hip dislocation occurrence
  • Gentle range of motion activities that do not cause dislocation
  • Wearing of Pavlik harness
    • The Pavlik harness is a soft splint used to allow for consistent contact between the acetabulum and the femoral head
      • Positioned in abduction of legs, hip flexion, and knee flexion through a series of straps to keep the infant in this position
    • Used for infants 6 months or younger, with a goal of 24-hour wear for the first 6 weeks, progressing to nighttime-only wear for the following 6 weeks
      • The parents must learn how to care for the baby fully during the period of continuous wear
      • Change from wearing 24 hours a day to only at night is determined by an orthopedic physician via x-ray and ultrasound
      • Developmental delay may occur in an infant due to constant positioning, as mentioned above, with decreased ability to move out of position

Example: Pavlik harness adherence

During the 24-hour wear phase, a parent asks the PTA to remove the harness for bathing.

Answer: The PTA reinforces the current wear schedule. Changing it is a physician decision based on follow-up imaging, not something the PTA or family adjusts on their own.

Clubfoot (talipes equinovarus)

Definitions
Clubfoot (talipes equinovarus)
A congenital deformity in which the foot is fixed in plantarflexion (equinus), hindfoot inversion (varus), forefoot adduction, and a high arch (cavus), with tight posterior and medial soft tissues including the Achilles tendon. Etiology is unknown, but it may be related to imbalanced development of the tendons and muscles of the foot during pregnancy, or to spina bifida.

Phases of intervention

  • Phase 1: serial casting
    • Clubfoot is stretched/manipulated to improve the range of motion, and then a hard cast is set in place over the affected extremity
      • The hard cast is removed, and stretching occurs again, with a new cast put in place with the new range of motion that has been achieved
      • The goal is to wear the hard cast until normal alignment is achieved - can take 4-10 weeks to achieve normal alignment
      • Most infants then undergo a percutaneous Achilles tenotomy to correct the remaining equinus before the final cast
  • Phase 2: bracing
    • Once serial casting is complete (normal alignment is achieved), bracing is put in place to aid in maintaining the normal alignment of the foot
      • A foot-abduction brace (boots on a bar) is worn about 23 hours a day for roughly 3 months, then during nighttime sleep and naps until about age 4
      • Non-adherence to bracing is the leading cause of relapse

Surgical intervention may be necessary depending on the severity of the deformity and the inability to change Achilles tendon length through conservative measures.

Metatarsus adductus is a common foot deformity usually noted at birth in which the forefoot turns inward.

Physical therapy interventions for clubfoot

Within the PT’s plan of care, the PTA may assist with stretching between casts, teach families how to put on the brace and check the skin, monitor motor milestones, and report skin breakdown, poor brace tolerance, or loss of correction to the supervising PT. Choosing or changing the brace is a PT or physician decision.

Osteogenesis imperfecta

Definitions
Osteogenesis imperfecta
A group of genetic disorders that impacts an individual’s ability to produce strong, healthy bones (most often a defect in the amount or structure of type I collagen, the most abundant protein in bone), increasing the risk of bone fractures with minimal impact.

Symptoms of osteogenesis imperfecta

  • Short stature
  • Joint laxity
  • Frequent fractures
  • Bone deformities
  • Muscle weakness
  • Hearing loss
  • Dental problems
  • Blue or gray-blue sclerae (a classic sign)

There are varying degrees of severity of osteogenesis imperfecta, ranging from mild symptoms that persist throughout life to severe symptoms in which the newborn dies within weeks of birth.

Rickets, which is usually not genetic (inherited forms such as X-linked hypophosphatemic rickets are rare), also causes soft, weak bones in children, usually because they do not get enough vitamin D, which helps growing bones absorb calcium and phosphorus. Symptoms include bone pain or tenderness, impaired growth, and deformities of the bones and teeth.

Physical therapy interventions for osteogenesis imperfecta

  • Support the trunk and limbs with open hands; never lift by the ankles or pull on a limb
  • Avoid twisting/torsional forces; use active or gentle assisted ROM only, never forceful stretching
  • Aquatic therapy allows safe strengthening with reduced joint stress
  • Education on swaddling, positioning, handling, and fall-prevention strategies as the child progresses through developmental milestones

Arthrogryposis multiplex congenita (AMC)

Definitions
Arthrogryposis multiplex congenita (AMC)
A rare, non-progressive congenital condition characterized by multiple joint contractures found in at least two different body areas, present at birth and resulting from limited fetal movement in the womb (fetal akinesia).

The condition is not a single disease but a clinical finding that may have several underlying causes, primarily involving the neuromuscular system. When a fetus does not move enough in utero, the joints do not develop normally and soft tissues such as muscles and tendons can become contracted.

Clinical presentation

  • Multiple joint contractures at birth (e.g., clubfoot, extended knees, flexed wrists, thumb-in-palm deformity)
  • Muscle hypoplasia or replacement of muscle tissue with fibrous or fatty tissue
  • Thin, atrophic limbs
  • No progressive neurological decline
  • Normal cognitive function in most cases

Medical and physical therapy management

  • Physical therapy: early passive range of motion and daily stretching to prevent worsening contractures, positioning and serial casting to correct deformities, strengthening of available muscle groups, and mobility/gait training with assistive devices (walkers, wheelchairs, KAFOs) as needed
  • Orthotic management: AFOs or KAFOs for ambulation, hand splints to improve function, and spinal orthoses if scoliosis develops
  • Surgical management: surgery (soft-tissue releases, tendon transfers, osteotomies) may follow if conservative care fails; post-op PT follows the surgeon’s protocol

AMC-related clubfoot is stiffer, more prone to relapse, and more often needs surgery than idiopathic clubfoot.

PTA role across these conditions: the PTA follows the PT’s plan - assisting with stretching, brace/orthosis wear, positioning, and ROM - rather than choosing orthoses or progressing casting independently. Report promptly: skin breakdown or loss of active knee kicking in a Pavlik harness (possible femoral nerve palsy), forced/excessive hip abduction (risk of avascular necrosis), and in OI, new pain, swelling, deformity, or refusal to move a limb (possible fracture).

Condition Core problem Key sign Main precaution
DDH Shallow acetabulum, hip instability Palpable clunk or limited abduction Avoid dislocating positions; follow Pavlik schedule
Idiopathic clubfoot Soft-tissue contracture Foot fixed down and inward at birth Maintain casting/bracing schedule
Osteogenesis imperfecta Defective bone collagen Frequent fractures, blue sclerae Gentle handling; no forceful ROM
AMC Limited fetal movement Multiple fixed contractures at birth Early, consistent stretching
Key points

Developmental dysplasia of the hip (DDH)

  • Shallow acetabulum allows femoral head to dislocate; risk factors: breech birth, first pregnancy, tight swaddling, female sex, family history
  • Key signs: leg length discrepancy, asymmetric thigh folds, limited hip abduction (>3 months); Ortolani (abduction reduces hip, clunk) and Barlow (adduction dislocates hip, clunk) tests
  • Treatment: Pavlik harness (hip flexion/abduction, knee flexion) worn 24hrs/day initially, then nights only—schedule changes only by physician via imaging, not PTA/family

Clubfoot (talipes equinovarus)

  • Foot fixed in plantarflexion, hindfoot varus, forefoot adduction, high arch; tight Achilles and medial tissues
  • Phase 1: serial casting (4-10 weeks) with repeated stretch/cast cycles, often followed by percutaneous Achilles tenotomy
  • Phase 2: foot-abduction brace (boots on bar), 23hrs/day initially tapering to nights until ~age 4; non-adherence = leading cause of relapse
  • PTA assists with stretching, brace education, skin checks; reports poor tolerance/loss of correction; brace changes are PT/physician decision

Osteogenesis imperfecta

  • Genetic disorders, most often a type I collagen defect, cause fragile bones, frequent fractures with minimal trauma
  • Symptoms: short stature, joint laxity, bone deformities, hearing loss, blue/gray-blue sclerae (classic sign)
  • PT care: support limbs with open hands (never lift by ankles/pull limbs), avoid twisting/forceful ROM, use aquatic therapy, educate on safe handling/positioning

Arthrogryposis multiplex congenita (AMC)

  • Non-progressive condition from limited fetal movement (fetal akinesia), causing multiple joint contractures in ≥2 body areas at birth
  • Features: muscle hypoplasia, thin atrophic limbs, normal cognition in most cases, no neurological decline
  • Management: early PT (passive ROM, stretching, serial casting, strengthening), orthotics (AFOs/KAFOs, hand splints), surgery if conservative care fails
  • AMC-related clubfoot is stiffer, more relapse-prone, more often needs surgery than idiopathic clubfoot

Cross-condition PTA role and precautions

  • PTA follows PT’s plan for stretching, bracing, positioning—does not independently choose/progress orthoses or casting
  • Report immediately: skin breakdown, loss of knee kicking in Pavlik (femoral nerve palsy risk), forced hip abduction (avascular necrosis risk), new pain/swelling/refusal to move in OI (possible fracture)

More from Congenital disorders

  • Congenital neurological and genetic disorders