1. Joint Pain – week 1 Case #1 for post-clinic group 1

2. Patient presentation #1 Brett is a 14 year old boy who presents in the office with knee pain. What questions would you want to elicit during the medical interview? 2

3. More of the story The pain occurs in both knees and has been going on for 6 weeks off and on. There was no initial injury but the pain became worse after he played soccer a couple of days ago. Rest helps a little. He hasn’t tried any medicines. He hasn’t noticed any fever or redness in his knees. 3

4. Identify the bony structures in the following diagram: 4

5. Physical exam What are the key components of a focused examination of the knee? What are the steps to performing them? How will they help you distinguish among various causes of knee pain? 5

6. Physical exam Brett has full range of motion of his hip, knee and ankle There is no tenderness along the major ligaments of the knee There is no effusion, redness or warmth The ligaments to stable to provocative testing You do notice some swelling on the anterior shin about 2-3 cm below the knee cap 6

7. Physical exam Why do we examine the hip and ankle when he is only complaining of knee pain? What are the major ligaments? Identify them in a diagram What tests can be done to assess for joint stability? How are they done? 7

8. What structure is the arrow pointing to? 8

9. What is happening in these x-rays? 9

10. Diagnosis Your attending physician examines Brett and tells him that he has Osgood-Schlatter disease, an apophysitis of the tibial tubercle – What is an apophysitis? – Why is it important that Brett is 14 years old? – What is the histologic structure of bone in a child? An adolescent? An adult? How are they different? 10

11. Pathology What are the muscles that control flexion and extension of the knee? What are their insertion points? Why do patients at this age have pain in this particular location? Brett has knee pain due to this injury. Discuss how the pain signal gets from his knee to his brain, tracing the anatomic pathway of the nerves. 11

12. Treatment Your attending tells Brett to rest for 1 week and take ibuprofen every 6 hours. – What is ibuprofen’s mechanism of action? – How might it exert its effects in this particular case? – The mother stops you to ask whether the ibuprofen will have any side effects for her son. How do you answer? 12

13. Patient presentation #2 A 2 year boy comes into the office for a health maintenance visit. His mother is concerned that his legs are bowed. What questions do you want to elicit during the medical interview? 13

14. More of the story On interview you learn that his legs have appeared bowed for several months and gradually seem to be getting worse. He also seems to have difficulty walking. The remainder of his development is appropriate. His past medical history is unremarkable. He is up to date on all his vaccines. He takes no medications and has no allergies. 14

15. More of the story He lives at home with his mother and two older sisters. His family emigrated from Somalia 3 years ago. He eats a variety of fruits and vegetables and drinks mainly breast milk. 15

16. Physical Exam On physical exam you notice a dark-skinned toddler with a waddling gait. His skull seems soft and “spongy”. His ears, nose and throat are unremarkable His chest is notable for bumpy lesions along his costochondral junctions. He has a varus deformity at the knees and his legs are bowed. 16

17. Physical Exam On physical exam you notice a dark-skinned toddler with a waddling gait. His skull seems soft and “spongy”. His ears, nose and throat are unremarkable His chest is notable for bumpy lesions along his costochondral junctions. He has a varus deformity at the knees and his legs are bowed. 17

18. X-rays 18

19. Diagnosis Your attending physician makes a diagnosis of vitamin D deficiency rickets. He orders some confirmatory lab tests and places the child on high dose vitamin D. – What would you expect on laboratory testing for a child with this condition? Why? – How might this disease have been prevented in this child? 19

20. Vitamin D Divide into groups and discuss the various ways that vitamin D can enter the body. Where is it processed? Why does it have an effect on bone formation? Draw a diagram illustrating the pathways of vitamin D absorption, activation and effect 20

21. Patient presentation #3 A 4 year old boy is brought to the emergency room complaining of pain in his left arm after falling at the playground. What additional questions would you want to elicit during the medical interview? 21

22. More of the Story The patient was climbing the monkey bars at preschool an hour prior to arrival when he slipped and fell. Per the daycare provider he fell on an outstretched left arm and started c/o pain immediately. His mother was called and noticed that his left wrist looked swollen. She brought him right to the emergency room. 22

23. Additional history The patient is otherwise healthy. He has had no previous injuries or chronic illnesses He takes no medications and has no known allergies. He lives with his mother and an older sister who is 7 years old and in 2 nd grade. He is up to date on immunizations. 23

24. Physical examination On physical exam he is a well appearing, well nourished child who is apprehensive when you approach him. You note swelling in the distal part of his left arm and wrist. You leave that part for last. His elbow, arm, fingers and hands all appear to have full range of motion and no tender areas. His right wrist is extremely tender on the thumb side—he refuses to move his wrist 24

25. X-ray Your attending physician is concerned about a possible fracture. He orders an x-ray. 25

26. X-ray 26 "Salter Harris 1 demo" by Gilo1969 - I (Gilo) created this work entirely by myself.. Licensed under CC BY 3.0 via Wikipedia - https://en.wikipedia.org/wiki/File:Salter_Harris_1_demo.jpg#/media/File:Salter_Harris_1_demo.jpg

27. Bone growth Draw a picture of a long bone labelling the following parts; epiphysis, diaphysis, metaphysis, physis. Describe how bone growth occurs in children including specifically the role of osteoblasts and osteoclasts. 27

28. Diagnosis Even though the x-ray does not show any fracture, the physician strongly suspects a Salter-Harris fracture to the distal radius based on the patient’s clinical presentation. He applies a cast and asks the patient to come back in 2 weeks for a follow up visit. 28

29. Treatment Discuss the healing process in bone after a fracture. What is remodeling? Why do we put a cast on patients who have a fracture? 29