A6-year-old girl presents with a limp. the parents noted that the girl was having difficulty walking for the past two days. they deny trauma or fever but did note a cold one week prior. on physical exam, the girl appears well and is afebrile, with the left hip held flexed and abducted. laboratory tests reveal normal erythrocyte sedimentation rate (esr), c-reactive protein (crp), and wbc. ultrasound shows the presence of joint effusion of the left hip. which of the following of the most likely diagnosis? a. myositis
b. septic arthritis
c. stress fracture
d. transient (toxic) synovitis

d. Transient (toxic) synovitis

Explanation:

From the symptoms stated in the question, the girl has suffered from  Transient (toxic) synovitis. Transient (toxic) synovitis results from inflammation in the synovium (inner linnings of the capsule) situated in the hip joint. Studies have shown that it is one of the most causes of hip pain in children.

It is known that symptoms can start suddenly before it  typically shows up within 1-2 weeks. At the earlier stage during 1-2 weeks, an upper respiratory illness is noticed in affected patients. The symptoms usually develop afterwards with acute pain in the depressed area of the thigh, the junction of the trunk at the  thigh, knee joints, hip and the srrounding region, thus the children walk with pain.

Also, in affected patient,they are often afebrile or have no or  low-grade fever.

Ultrasound shows the presence of joint effusion(fluid collection) of the left hip causing monoarticular disorder of synovial joints, Hence,the hip is held flexed or abducted. Treatment includes Clinical  administration of nonsteriodal anti-inflammatory drugs and weight barrier capable of  inducing the patient by exertion some force and pressure towards the weight should be limited.

b is the correct answer