1. 61 yo M with knee pain. ? Medial meniscal tear

3. Knee pain

26. Intramuscular dissection of Popliteal Cyst Pop Cyst – fluid distension of the gastrocnemius-semimembranosus bursa Joint fluid through a weakened posteromedial joint capsule Usually extend inferomedially- path of least resistance ? weakened fascia around muscle- predispose to IM dissection Skeletal Radiol. 2004 Jun;33(6):367-71. Epub 2004 Mar 9.

27. Sag PD 38 yo M with mass that developed over 6-8 weeks. No history of trauma

28. Sag T2 38 yo M with mass that developed over 6-8 weeks. No history of trauma

29. Sag T2 FS 38 yo M with mass that developed over 6-8 weeks. No history of trauma

30. Sag T1FS Gd 38 yo M with mass that developed over 6-8 weeks. No history of trauma

31. Axail PD 38 yo M with mass that developed over 6-8 weeks. No history of trauma

32. Axail T1 38 yo M with mass that developed over 6-8 weeks. No history of trauma

33. Axail T1FS Gd 38 yo M with mass that developed over 6-8 weeks. No history of trauma

34. Axail T1FS Gd 38 yo M with mass that developed over 6-8 weeks. No history of trauma

35. 13 y.o male with right knee pain for several months. Osgood-Schlatter’s clinically. ? Osteochondral lesion

47. OCD Juvenile OCD usually between 10-20 yrs Athletically active children Classic location – lateral aspect of medial femoral condyle Believed to be due to repetitive microtrauma

48. OCD Stable lesions in skeletally immature pts – conservative management Subchondral bone attached to cartilage or not - Hyaline cartilage lacks blood vessels and has limited ability to heal

49. Osteochondritis (osteochondrosis) dissecans: a review and new MRI classification. Eur Radiol. 1998;8(1):103-12. Review. Evolution of OCD

50. Osteochondritis dissecans of the knee in children.Curr Opin Pediatr. 2003 Feb;15(1):38-44. Review Osteochondritis dissecans of the knee in children.Curr Opin Pediatr. 2003 Feb;15(1):38-44. Review

51. Osgood Schlatter’s Tendinosis or partial tear Distended deep infrapatellar bursa was a frequent finding – assc pain and inflammation Ossicle seen only in 32% cases - remained non united in some after relief of Sx. Most cases of OS - insult to the tendon and associated soft tissues, rather than avulsion fracture Radiology. 1992 Dec;185(3):853-8. Osgood-Schlatter lesion: fracture or tendinitis? Scintigraphic, CT, and MR imaging features.

52. Osgood Schlatter’s Distended deep infrapatellar bursa was seen on MRI in 71% of cases Average DIB dimensions on T2WI AP 2.1-2.7 mm craniocaudal 7.3-9.1 mm

53. Calf pain

54. Feathery appearance of the medial head of the gastrocnemius Adjacent hematoma Grade II partial tear of the medial head of the gastrocnemius

55. Tennis leg Intact plantaris tendon on axial images

56. Tennis leg

57. US findings in the 141 patients rupture of the medial head of the gastrocnemius muscle (66.7%), fluid collection between the medial gastrocnemius and soleus muscles without muscle rupture (21.3%), rupture of the plantaris tendon (1.4%), partial rupture of the soleus muscle (0.7%). Deep venous thrombosis (9.9%). Tennis Leg: Clinical US Study of 141 Patients and Anatomic Investigation of Four Cadavers with MR Imaging and US1 Gonzalo J. Delgado, MD2, Christine B. Chung, MD, Nitaya Lektrakul, MD, Patricio Azocar, MD, Michael J. Botte, MD, Daniel Coria, MD, Enrique Bosch, MD and Donald Resnick, MD2

58. 9 yr old ballerina with anterior knee pain

60. Possible stress fracture Stress fractures in athletes tibia (50%) tarsal bones (25%) metatarsals (9%), femur (7%) fibula (6%), pelvis (1.5%), sesamoids (0.9%), and spine (0.6%)..[[ Mata SG, Grande MM, Ovejero AH. Transverse stress fracture of the patella. Clin J Sport Med 1996;6:259–61

61. Patellar stress fracture Described with bone-patellar tendon- bone anterior cruciate ligament reconstructions patella resurfacing in total knee arthroplasty

62. Childhood patellar stress fracture Unusual. 16 cases described Transverse patellar stress fractures Rare Dickason JM, Fox JM. Fracture of the patella due to overuse syndrome in a child. Am J Sports Med 1982;10:248-249 Mata G, et al. Transverse stress fracture of the patella in a child. J Pediatr Orthop B. 1999 Jul;8(3):208-11.

63. Patellar stress fractures Case report :35 yo recreational tennis player Anterior Knee Pain Declined surgical management Sudden onset of increased pain after walking down stairs Propagation of stress fracture of the patella – Crowther et al_ 39 (2) e6 -- British Journal of Sports Medicine

64. Considerations Stress fracture on the tensile superficial surface of the patella is at risk of complete fracture Non-operative treatment for those not immediately returning to activity patients involved in high demand sports require prophylactic internal fixation