61 yo M with knee pain. ? Medial meniscal tear

Knee pain

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 Jun;33(6): Epub 2004 Mar 9.

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

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

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

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

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

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

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

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

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

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

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

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

Osteochondritis dissecans of the knee in children.Curr Opin Pediatr Feb;15(1): Review Osteochondritis dissecans of the knee in children.Curr Opin Pediatr Feb;15(1): Review

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 Dec;185(3): Osgood-Schlatter lesion: fracture or tendinitis? Scintigraphic, CT, and MR imaging features.

Osgood Schlatter’s Distended deep infrapatellar bursa was seen on MRI in 71% of cases Average DIB dimensions on T2WI AP mm craniocaudal mm

Calf pain

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

Tennis leg Intact plantaris tendon on axial images

Tennis leg

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

9 yr old ballerina with anterior knee pain

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

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

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: Mata G, et al. Transverse stress fracture of the patella in a child. J Pediatr Orthop B Jul;8(3):

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

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