Hutchins, Keith L. DHSc, PA-C
A 14-year-old male patient with a history of Down syndrome came for orthopedic evaluation after being referred by his pediatrician. The patient's parents related that he had intermittent right hip pain for more than 3 months; the pain became chronic over the past 2 months resulting in increasingly painful gait. Over the past 12 months, the pediatrician saw the patient on several occasions and told the parents that their son probably had a hip muscle strain that would improve over time. The parents related no trauma history or increased activity for the patient during this time period.
During the initial orthopedics visit, the parents also relate having discussed with the pediatrician a need for increased speech therapy for their son and his significant weight gain over the past 12 months. They said that no screening tests were conducted. Three weeks before this initial orthopedics visit, the parents insisted on obtaining a radiograph of the patient's right hip. This was obtained by the pediatrician, and read by the hospital radiologist as normal. Again at the insistence of the parents, child was referred to orthopedics for further evaluation of his hip pain.
History The patient was born full-term weighing 6 pounds, 8 ounces. He had no complications at birth and was diagnosed with Down syndrome shortly after delivery. His development history has been delayed; at the time of referral, he was in a special education program. He has no history of hospitalizations since birth. He has chronic constipation that is treated with laxatives, and a history of ear infections treated in outpatient care. Family history includes type 2 diabetes on the maternal side of the family, and no history of hypertension, hypercholesterolemia, or thyroid disease on either side of the family.
The patient started to have difficulties with speech, swallowing, and weight gain about 12 months before the development of right hip pain. The parents reported these concerns to their son's pediatrician. They deny that any specific testing or referral for hip or speech evaluation have been performed. He also reportedly gained about 30 pounds during this period and became less active according to his parents. They reported that over 3 to 4 months before the orthopedic evaluation, their son started to complain of intermittent right hip pain that gradually worsened, causing him to limp and further decreasing his activity level.
Orthopedic evaluation The patient was seen in the orthopedic clinic 3 weeks after referral by his pediatrician. He entered the clinic with an obvious limp and painful gait. The parents related his history; although the patient is pleasant and attempts to answer questions put to him directly, his poor speech and verbal skills mean that he essentially can only answer yes and no to questions.
Examination of the pelvis and lower extremities revealed no tenderness to palpation of the lumbar spine, sacroiliac joints, bony pelvis, greater trochanteric areas, the muscle groups of the upper or lower leg, knee, ankle, or feet bilaterally. He did exhibit pain in the right hip with attempts at internal and external rotation. Arc of motion showed zero degrees with internal rotation, and 40 degrees with external rotation. No discomfort or decreased arc of motion was noted on examination of the left hip. Neurovascular examination noted no sensory or motor deficits in the upper or lower extremities. He was also noted to have very dry skin, no lymphadenopathy, an apparent thickened tongue, and difficulty swallowing water (observed after the patient indicated he was thirsty while in clinic); no enlarged thyroid or nodules were found on examination. His weight was 151 pounds (68 kg) and height was 57 inches (144.8 cm), with a calculated body mass index of 34. No other abnormal findings were noted on the remainder of the examination.
A review of plain film anteroposterior and frog-leg lateral radiographs of both hips, ordered by the pediatrician, showed an abnormal-appearing right femoral epiphysis as compared to the left (Figure 1 shows a similar abnormality in another patient). The abnormality did not have the clear appearance of a slipped capital femoral epiphysis, and an MRI study of the right hip was ordered and done on the same day of the visit. MRI results showed a grade I (0% to 33%) slipped capital femoral epiphysis of the right hip. Comparison MRI views of the left hip showed no abnormalities.
Treatment The patient was admitted to the hospital for immediate surgical treatment of the slipped capital femoral epiphysis. He was taken to the OR, where a single cannulated screw was used for in situ fixation of the slipped capital femoral epiphysis. He had an uneventful recovery.
While in the hospital, the patient had screening bloodwork done for thyroid disease and diabetes. Results of these tests showed a significantly elevated thyroid stimulating hormone (TSH) level of 97 μIU/mL (normal value 0.3 to 5 μIU/mL), and a non-fasting glucose of 120 mg/dL (normal range, 70 to 105 mg/dL). He was discharged on postoperative day two on crutches and partial weight bearing on the right leg. He was not placed on any thyroid medications, but was urgently referred to a pediatric endocrinologist for evaluation and treatment of his thyroid disorder and elevated glucose level.
Four days after his hospital discharge, the patient was seen by a pediatric endocrinologist. The parents again related his history and he had a full physical examination. Additional laboratory work was ordered with the following results: anti-thyroglobulin thyroid AB, positive (normal is negative); antimicrosomal thyroid AB, positive (normal is negative); TSH, 96.95 μIU/mL (normal range, 0.34 to 5.66 μIU/mL); free thyroxine, 0.33 ng/dL (normal range, 0.52 to 1.21 ng/dL); hemoglobin A1C, 5.9% (normal range, 4.3% to 6%); insulin, 96.3 μU/mL (normal range, 1.9 to 23 μU/mL); glucose, 98 mg/dL (normal range, 70 to 110 mg/dL); C-peptide, 15.9 ng/mL (normal range, 0.9 to 4.5 ng/mL).
He was started on levothyroxine sodium at 12.5 mcg daily, graduating up 100 mcg over the next 4 months. His primary diagnosis from endocrinology was hypothyroidism, insulin resistance, and Down syndrome. He was also scheduled to receive additional screening in the Down syndrome clinic. Repeat laboratory testing at 4 months revealed a TSH of 10.95 μIU/dL, A1C of 5.3%, and free thyroxine of 0.80 ng/dL.
Routine follow-up in the orthopedic clinic at 3 months revealed an adolescent male with no limp, and able to walk and bend well. Repeat radiographs of the pelvis showed the cannulated screw in the right hip to be in place and the left hip to be stable without evidence of a slipped capital femoral epiphysis. The parents were advised that he should be followed yearly for the next 2 to 3 years to ensure no complications of the right hip and reevaluate the left hip as needed for slipped capital femoral epiphysis.
Early screening and detection should be a hallmark of primary care and prevention programs, especially for patients at high risk for associated diseases. The initial provider in this case had the opportunity to do early screening for his patient, but apparently did not. Both slipped capital femoral epiphysis and hypothyroidism require a high level of suspicion, screening, and early referral to avoid long-term complications (Table 1).
Down syndrome is associated with cardiac, gastrointestinal, skeletal, thyroid, and hearing disease and disorders, as well as diabetes and dementia (Table 2). Children with Down syndrome are at higher risk for thyroid disorders and slipped capital femoral epiphysis. Although no direct correlation between thyroid disease and slipped capital femoral epiphysis exists, they do occur at a higher rate individually in patients with Down syndrome than in the general population.1 Routine screening for thyroid disorders (and other disorders related to Down syndrome) has been recommended by the American Academy of Pediatrics, but many providers have failed to do so unless regularly reminded.2 Two studies of the cost and effectiveness of screening for hypothyroidism concluded that the cost is minimal and if done routinely can be very effective in identifying children with thyroid disorders.3,4
Providers should be vigilant and suspect slipped capital femoral epiphysis in any child who presents with hip, thigh, or knee pain. Misdiagnosing this condition as a pulled muscle or sprain of the hip or knee without careful examination of the hip and leg puts the patient at risk for long-term complications, such as avascular necrosis and early degenerative changes that may lead to the need for total hip arthroplasty at a young age.5 Two articles provide detailed evaluations of hip radiographs for the diagnosis of slipped capital femoral epiphysis and other hip disorders, along with their treatments and outcomes if diagnosis is missed.5,6
Primary care providers must be vigilant for these two conditions, especially in children under age 15 and those with conditions such as Down syndrome. Routine screening and examination is important for patients who are at higher risks for diseases than the general population. Providers also should be more willing to refer patients for further evaluation if in any doubt as to the cause of the patient's complaints. Listen to patients (or as in this case, their parents or guardians) and address their concerns early with screening examinations or testing. When making a diagnosis, don't fully rely on the results of tests (in this case, radiographs) that may have been incorrectly interpreted. Leaving this patient's conditions untreated could have resulted in serious complications.
1. Brenkel I, Dias J, Iqbal S, Gregg P. Thyroid hormone levels in patients with slipped capital femoral epiphysis. J Pediatr Orthopedics
2. Carroll K, Arbogast P, Dudley J, Cooper W. Increase in incidence of medically treated thyroid disease in children with Down syndrome following re-release of American Academy of Pediatrics Health Supervision Guidelines. Pediatrics
3. Danese M, Powe N, Sawin C, Ladenson P. Screening for mild thyroid failure at the pediatric health examination: A decision and cost effectiveness analysis. JAMA
4. Murphy J, Philip M, Macken S, et al. Thyroid dysfunction in Down's syndrome and screening for hypothyroidism in children and adolescents using capillary TSH measurement. J Pediatr Endocrinol Metabolism
7. Dietz F, Albanese S, Katz D, et al. Slipped capital femoral epiphysis in Down syndrome. J Pediatr Orthopedics
8. Green D, Reynolds R, Khan S, Tolo V. The delay in diagnosis of slipped capital femoral epiphysis: a review of 102 patients. HSSJ
© 2013 American Academy of Physician Assistants.