Approach to a limp (pediatrics): Clinical sciences

Chapters:

Watch video only

Introduction0:00–0:36

A limp is a gait abnormality that’s usually caused by pain, weakness, or deformity, and if it goes unrecognized, it can lead to permanent disfigurement and loss of function.
Based on history, exam, and imaging findings, you can differentiate between a painful limp, which is typically associated with infectious, traumatic, inflammatory, or mechanical causes; and a painless limp, which can occur due to mechanical or developmental causes.

Focused H&P0:36–1:05

When a child presents with a limp, begin by obtaining a focused history and physical exam, including a thorough musculoskeletal and neurologic exam.
Keep in mind that young children may not be able to describe their pain well, so in non-verbal children, look for indicators of pain, such as irritability, crying, or refusal to stand or walk.

Painful limp - Sudden onset1:05–1:39

Okay, now your first step when evaluating a limp is to assess for pain. If the patient is presenting with a painful limp, your next step is to assess the onset of the limp, which could be either sudden or gradual.
Any painful limp with a sudden onset, should make you consider infection, so assess for the presence of fever. If fever is present, the main causes to consider include septic arthritis, meaning an infection of the joint, and osteomyelitis, which is an infection of the bone.

Septic arthritis1:39–2:49

First, let’s discuss septic arthritis. These individuals may report joint swelling and pain, with refusal to bear weight on the affected extremity.
The physical exam might reveal joint tenderness, effusion, and warmth, as well as a limited range of motion. In addition, you may observe that the child "guards" the joint.
At this point, consider septic arthritis and order labs, including a CBC, CRP, ESR, and a blood culture. Additionally, perform a joint aspiration to collect synovial fluid for analysis and culture.
The labs will typically show elevated WBCs, CRP, and ESR, and sometimes, blood cultures might reveal a causative pathogen.
The synovial fluid will likely appear purulent, with WBCs greater than 50,000, and possible growth on culture. With these findings, you can confirm the diagnosis of septic arthritis.Now, let's switch gears and discuss osteomyelitis.

Osteomyelitis2:49–3:56

This is usually associated with localized bony pain. There may also be a history of immunosuppression.
Physical exam will reveal point tenderness with localized warmth and swelling. In addition, the child will have pain on weight bearing, usually felt over the metaphysis.
These findings should make you consider osteomyelitis, so again, order CBC, CRP, ESR, and a blood culture. In addition, order an X-ray, and, if needed, MRI for better visualization.
Labs will reveal an elevated WBC, CRP, and ESR with possible growth on blood culture; while imaging studies will show evidence of osteolysis and bone destruction, and if there is still uncertainty, nuclear imaging can be done.
At this point, diagnose osteomyelitis. Now, let’s go back and consider the causes of a sudden painful limp in which there’s no fever; starting with bone fractures.

Bone fractures3:56–4:40

The child may present with localized pain and inability to bear weight on the affected leg after a known trauma. Physical exam could reveal point tenderness or an area of swelling or bruising.
Additionally, you might notice a visible deformity of the affected limb. These findings should make you consider bone fracture.
Your next step is to order an X-ray, which will show the location and severity of bone fracture, confirming that what’s causing the limp is indeed a fracture.Next is soft tissue injury.

Soft tissue injury4:40–5:20

This child will also complain of localized pain, but they may also describe a sudden “pop” at the time of injury. There will be localized tenderness and swelling, and they might have ligamentous laxity.
All of these findings should lead you to consider a soft tissue injury. Depending on the suspected injury, your next step might be to order an MRI, which will help you identify injury of the muscle, ligament, or tendon, and confirm the diagnosis of soft tissue injury.Let’s move on to non-accidental trauma, which can be challenging to diagnose.

Non-accidental trauma5:20–6:26

A worrisome sign of non-accidental trauma is any injury that’s out of proportion to the mechanism described. Red flags on physical exam include unusual or patterned bruising, such as of the auricle of the ear; any type of oral injury; or burn marks on the skin.
If you see any of these, you must consider non-accidental trauma. Your next step is to order a skeletal survey to look for evidence of previous injuries.
If you detect multiple fractures in various stages of healing, then you can diagnose non-accidental trauma.Now, here’s a clinical pearl!
Non-accidental trauma is not limited to bones only, so be sure to evaluate for intracranial bleeding, abdominal trauma, and other signs of maltreatment or neglect.

Transient Synovitis6:26–7:25

Okay, now, let’s go back and take a look at individuals with a sudden painful limp, with no fever or trauma, which should make you think of transient synovitis.
These patients typically present with hip pain and a recent upper respiratory tract infection. On the exam, the child is well-appearing with their hip abducted and externally rotated because internal hip rotation is painful.
In this case, consider transient synovitis of the hip, and order a CBC, CRP, and ESR; as well as a bilateral hip ultrasound.
Unlike in septic arthritis, the WBC, CRP, and ESR will be normal, with possible unilateral or bilateral hip effusion on ultrasound.
Based on these findings, you can diagnose transient synovitis.Okay, now that we’re done with painful limp with sudden onset, let’s switch our focus to gradual onset.

Painful limp - Gradual onset7:25–7:33

SCFE7:33–8:36

Let’s start with slipped capital femoral epiphysis, or SCFE. SCFE is typically seen in children older than 10 years of age, and presents with pain in the hip, groin, thigh, or knee.
Some important risk factors for SCFE include obesity, hypothyroidism or other endocrinopathies, trauma or radiation therapy, and family history of SCFE.
Additionally, physical exam will reveal limited internal rotation, abduction, and flexion of the hip. Often, you’ll notice the child’s leg externally rotating as you passively flex the hip.
Sometimes, the hip could even be tender to palpation. With these findings, you should consider SCFE, so proceed with bilateral hip X-rays.
If imaging reveals unilateral or bilateral femoral head displacement, you can confirm the diagnosis of SCFE.Next up is Legg-Calve-Perthes Disease, or LCPD.

LCPD8:36–9:48

These patients are usually less than 8 years old, and classically present with a painless limp, usually unilateral. However, patients with more severe disease may develop a painful limp and could report pain in the hip, as well as the groin, thigh, or knee.
Risk factors for LCPD include being biologically male or having a family history of LCPD. The physical exam of a child with LCPD will often reveal limited internal rotation and abduction of the affected hip.
Additionally, while your patient is standing or walking, you might notice the Trendelenburg sign, which is a pelvic tilt caused by hip muscle weakness.
All of these findings should make you consider LCPD. Your next step is to order a bilateral hip X-ray, which typically reveals a widening of joint space and, in more severe cases, flattening or fragmentation of the femoral head with sclerosis, confirming the diagnosis of LCPD.Now, let’s consider overuse injury.
This usually affects older children who participate in repetitive exercise or sports, and they usually report pain that worsens with activity.

Overuse injury9:48–10:26

On physical exam, you will notice areas of localized tenderness, with or without localized swelling. With these findings, you should consider overuse injury.
Your next step is to assess symptoms after a trial of rest; if symptoms improve or resolve, you can diagnose overuse injury.

Bone tumor10:26–11:07

Our last cause of a painful limp are bone tumors. Patients may report localized bone pain that occurs at night or during rest.
The exam may reveal point tenderness that could be associated with localized swelling or a palpable mass. These findings are red flags that should make you immediately consider the possibility of a bone tumor!
Your next step is to order an X-ray of the affected part. If imaging reveals a bone lesion, which may show concerning findings such as “onion skinning” or “sunburst” pattern, diagnose a bone tumor!Alright, let’s go all the way back and consider a limp that occurs with no pain.

Painless limp11:07–11:16

Let’s start with developmental dysplasia of the hip, or DDH. DDH is usually diagnosed during well child visit screenings before the child starts walking, but, sometimes, it can be discovered in an ambulatory child, usually between 2 to 5 years.

DDH11:16–12:08

Some risk factors include breech position during gestation, or family history of DDH. On exam, you will typically notice a limited hip ROM, a short thigh segment, and asymmetric thigh or gluteal skin folds.
With this spectrum of findings, you should consider DDH, so order bilateral hip X-rays. If the imaging shows hip asymmetry and delayed ossification with subluxation or dislocation of the femoral head, you can diagnose DDH.Next, let’s talk about juvenile idiopathic arthritis, or JIA.
This is an autoimmune condition that can present with limp when the knee or ankle joints are affected. A child with JIA is likely to describe more than 6 weeks of morning stiffness and one or more swollen joints.

JIA12:08–12:51

Although it’s rare, some patients also report joint pain. On exam, you may notice effusion and warmth in one or more joints, along with tenderness or limited range of motion.
With these findings, you can diagnose JIA.Another condition to consider is developmental delay. Some children may have delayed motor milestones that cause a limp, and caregivers may also report concerns about the child’s development.

Developmental delay12:51–13:20

On the exam, you could notice abnormalities in muscle tone, posture, coordination, or reflexes. These findings are consistent with developmental delay.
Finally, some painless limps are associated with an angular limb deformity. These children can be described as having an unusual posture or gait, and there might be a history of a unilateral injury.

Angular limb deformity13:20–13:55

You may appreciate a valgus or varus leg position while the child is standing; see a lateral or medial knee thrust when they walk; or identify a leg length discrepancy upon measurement.
These physical exam findings indicate an angular limb deformity.Alright, as a quick recap… A limp is an abnormality in gait that is caused by pain, weakness, or deformity.

Review13:55–14:53

Limps can be painful or nonpainful. Painful limps are first differentiated by acuity, with sudden onset further differentiated by the presence of fever, indicating infection like septic arthritis or osteomyelitis; by the presence of trauma, indicating injury or possible non-accidental trauma; or by a lack of fever or trauma, indicating possible transient arthritis.
On the other hand, the gradual onset of painful limp is more indicative of SCFE, LCPD, overuse injury, or a bone tumor. Finally, limps associated with little to no pain may include DDH, JIA, developmental delay, or angular limb deformity.
more indicative of skiffy L CPD overuse injury or a bone tumor Finally lymphs associated with little to no pain may include D DH JIA a developmental delay or angular