AAP National Conference & Exhibition 2022
Section on Orthopaedics-POSNA Young Investigator Awards
Epidemiology of Preschool-Age Children Presenting to the Orthopaedic Clinic with Limping
Boston Children’s Hospital, Boston, MA
Volume 5, Number 2, May 2023
Hip/Lower Extremity
Recipient: Blair Stewig, BS
Abstract
Background: Limping in preschool-age children is a common chief complaint in the orthopaedic clinic. Given the breadth of limping etiologies, there is variability in the evaluation of these patients. The objectives of our study are: 1) to describe the epidemiology of preschool-age children presenting with limp and 2) to determine predictors identifying children at risk for non-benign etiologies.
Methods: This is a retrospective study of children <6 years old presenting to a tertiary care pediatric orthopaedic clinic with a chief complaint of limping from 1/1/2019 to 12/31/2020. Subjects were identified from the electronic medical record using natural language processing. Exclusion criteria included: limp >3 weeks, lower extremity fracture or surgery <12 weeks, or chronic conditions affecting the lower extremity (i.e., malignancy, neuromuscular disorder, sickle cell disease). Patient demographic and clinical characteristics were collected. Outcome diagnoses were classified as “benign,” “receiving advanced treatment (i.e., antibiotics, steroids, surgery),” or “inconclusive.” We calculated frequencies of outcomes and compared them using the Chi-square test. Bivariate analyses were conducted using Student’s t-test, the Mann-Whitney U-test, or chi-square test. We conducted a multivariable logistic regression analysis to determine predictors associated with the outcome of receiving advanced treatment vs. benign/inconclusive diagnoses while controlling for patient characteristics.
Results: We identified 169 children <6 years old with limping: 105 benign causes (62%), 27 receiving advanced treatment (16%), and 37 inconclusive diagnoses (22%). The most common diagnoses among those receiving advanced treatment were juvenile idiopathic arthritis (8/27, 30%) and Lyme disease (7/27, 26%) (Table 1). On bivariate analysis, increased odds for requiring advanced treatment were identified for females (OR 2.8, 95% CI 1.20, 6.44) and presence of joint edema (OR 5.3, 95% CI 2.11, 13.47) (Table 2). Multivariate logistic regression found increased odds of receiving advanced treatment for females (OR 3.05, 95% CI 1.13, 8.24), joint edema (4.49, 95% CI 1.48, 13.61), and limp >9 days (OR 3.43, 95% CI 1.24, 9.51).
Table 1. Patient and Diagnosis Characteristics
All subjects (N=169) | Advanced treatment (n=27) | Benign/inconclusive (n=142) | |||||
---|---|---|---|---|---|---|---|
Characteristic | Freq. | (%) | Freq. | (%) | Freq. | (%) | P |
Age at presentation (years; mean (SD)) | 3.3 | (1.44) | 3.5 | (1.63) | 3.3 | (1.40) | 0.57 |
Sex (% male) | 110 | (65%) | 12 | (44%) | 98 | (69%) | 0.03 |
Diagnosis | |||||||
Juvenile idiopathic arthritis | 8 | (5%) | 8 | (30%) | 0 | (0%) | |
Lyme | 7 | (4%) | 7 | (26%) | 0 | (0%) | |
Other | 6 | (4%) | 3 | (11%) | 3 | (2%) | |
Legg-Calves-Perthes disease | 3 | (2%) | 3 | (11%) | 0 | (0%) | |
Reactive arthritis | 2 | (1%) | 2 | (7%) | 0 | (0%) | |
Developmental dysplasia of the hip | 1 | (1%) | 1 | (4%) | 0 | (0%) | |
Septic arthritis | 1 | (1%) | 1 | (4%) | 0 | (0%) | |
Stress Fracture | 1 | (1%) | 1 | (4%) | 0 | (0%) | |
Kohler disease | 1 | (1%) | 1 | (4%) | 0 | (0%) | |
Transient synovitis | 64 | (38%) | 0 | (0%) | 64 | (45%) | |
Toddler fracture | 19 | (11%) | 0 | (0%) | 19 | (13%) | |
Soft tissue injury or contusion | 9 | (5%) | 0 | (0%) | 9 | (6%) | |
Toddler fracture (foot) | 6 | (4%) | 0 | (0%) | 6 | (4%) | |
Reactive synovitis | 3 | (2%) | 0 | (0%) | 3 | (2%) | |
No conclusive diagnosis | 38 | (23%) | 0 | (0%) | 38 | (27%) |
Conclusion: The majority of preschool-age children presenting with limp had benign diagnoses. Understanding predictors for specific etiologies of limping “receiving advanced treatment” may assist in standardizing care for preschool children with limping.
Reprinted with Permission from AAP. The Young Investigator Awards (YIA) recognize the best abstract presentations by residents, fellows, and students at the annual scientific session during the National Conference & Exhibition.
Table 2. Presentation and Clinical Characteristics by Diagnosis Category
All subjects (N=169) | Advance treatment (n=27) | Benign/ inconclusive (n=142) | |||||
---|---|---|---|---|---|---|---|
Characteristic | Freq. | (%) | Freq. | (%) | Freq. | (%) | P |
Laterality | 0.39 | ||||||
Left | 71 | (42%) | 14 | (52%) | 57 | (40%) | |
Right | 89 | (53%) | 11 | (41%) | 78 | (55%) | |
Unclear | 9 | (5%) | 2 | (7%) | 7 | (5%) | |
Presenting location | 0.26 | ||||||
Orthopaedic clinic | 113 | (67%) | 15 | (56%) | 98 | (69%) | |
Urgent clinic | 56 | (33%) | 12 | (44%) | 44 | (31%) | |
Previous treatment | 143 | (85%) | 23 | (85%) | 120 | (85%) | 0.50 |
PCP | 117 | (81%) | 19 | (83%) | 98 | (82%) | >0.99 |
ED | 31 | (21%) | 4 | (17%) | 27 | (23%) | 0.79 |
Duration of limp (days; median (IQR)) | 5 | (2-10) | 6 | (2-13) | 5 | (2-10) | 0.39 |
Pain | 90 | (53%) | 18 | (67%) | 72 | (51%) | 0.20 |
Morning stiffness | 12 | (7%) | 4 | (15%) | 8 | (6%) | 0.25 |
Tick bite | 3 | (2%) | 1 | (4%) | 2 | (1%) | 0.98 |
Previous infection | 56 | (33%) | 11 | (41%) | 45 | (32%) | 0.49 |
Upper respiratory infection | 34 | (61%) | 4 | (36%) | 30 | (67%) | 0.13 |
Strep | 4 | (7%) | 0 | (0%) | 4 | (9%) | 0.71 |
Flu | 4 | (7%) | 2 | (18%) | 2 | (4%) | 0.35 |
viral infection | 7 | (13%) | 2 | (18%) | 5 | (11%) | 0.90 |
Ear infection | 9 | (16%) | 2 | (18%) | 7 | (16%) | >0.99 |
Hand foot, and mouth disease | 2 | (4%) | 1 | (9%) | 1 | (2%) | 0.85 |
Minor trauma | 28 | (17%) | 4 | (15%) | 24 | (17%) | 0.99 |
Fall | 17 | (57%) | 3 | (75%) | 14 | (58%) | 0.94 |
Blunt injury | 1 | (3%) | 1 | (25%) | 0 | (0%) | 0.30 |
Sport/playground | 9 | (30%) | 0 | (0%) | 9 | (38%) | 0.36 |
Hx of refusal to bear weight | 111 | (66%) | 16 | (59%) | 95 | (67%) | 0.59 |
Weight-bearing | 0.50 | ||||||
No | 12 | (7%) | 3 | (11%) | 9 | (6%) | |
Yes, fully | 56 | (33%) | 6 | (22%) | 50 | (35%) | |
Yes, with limp | 96 | (57%) | 18 | (67%) | 78 | (55%) | |
Yes, partially | 3 | (2%) | 0 | (0%) | 3 | (2%) | |
Unknown | 2 | (1%) | 0 | (0%) | 2 | (1%) | |
Swelling/edema | 27 | (16%) | 11 | (41%) | 16 | (11%) | <0.001 |
Skin sign | 11 | (7%) | 2 | (7%) | 9 | (6%) | >0.99 |
Bruising | 3 | (27%) | 1 | (50%) | 2 | (22%) | >0.99 |
Rash | 3 | (27%) | 0 | (0%) | 3 | (33%) | 0.94 |
Abrasions | 2 | (18%) | 0 | (0%) | 2 | (22%) | >0.99 |
Redness | 1 | (9%) | 1 | (50%) | 0 | (0%) | 0.39 |
Warm to touch | 1 | (9%) | 0 | (0%) | 1 | (11%) | >0.99 |
Other | 1 | (9%) | 0 | (0%) | 1 | (11%) | >0.99 |
Localized tenderness | 33 | (20%) | 6 | (22%) | 27 | (19%) | 0.74 |
Time from limp onset to presentation (days; median (IQR)) | 5 | (2-10) | 6 | (2-13) | 5 | (2-10) | 0.42 |
Time from presentation to diagnosis (days; median (IQR)) | 0 | (0-4) | 4 | (0-26) | 0 | (0-0) | <0.001 |
Time from presentation or follow-up (days; median (IQR); N=88)* | 28 | (12-197) | 306 | (31-655) | 22 | (8-58) | 0.003 |
*The number in parentheses represents the number of patients with available data for the given characteristic.
IQR, interquartile range; SD, standard deviation.