MSK-11 · Knee Meniscus, Patellofemoral, and Overuse

Knee Meniscus, Patellofemoral, and Overuse. Part of the Musculoskeletal series of the Reflex PM&R Board Review podcast. Audio corrections: (1) In the audio: We also talked about how the second fracture acts as a pathognomonic sign for an anterior cruciate ligament tear. — Correct: It is the Segond fracture, a lateral tibial plateau avulsion from an internal-rotation/varus injury, that is pathognomonic for ACL tear. There is no entity called a "second fracture." (2) In the audio: Level walking on a flat surface creates a compressive force equal to 0.9 times body weight across the patella-femoral joint. — Correct: The board-keyed ladder is about 0.5 times body weight walking, 3.3 times on stairs, and 6 to 7 times in a deep squat. Modern measurements put the squat peak lower (above 3 times), but answer the exam with 0.5 / 3.3 / 6-7. (3) In the audio: The true number is above 3 times body weight. — Correct: For the exam, deep squatting is keyed at 6 to 7 times body weight; the lower modern figure is a caveat, not the answer. (4) In the audio: Because the contact area between the articular surface of the patella and the trochlear groove is maximal at that point. — Correct: Patellofemoral contact area grows with flexion. The joint reaction force is lowest in terminal extension because the quadriceps compresses the patella against the femur least near full extension, and that force climbs steeply with flexion. (5) In the audio: get 6 to 12 weeks of strict conservative management. — Correct: A stable OCD lesion with open physes is managed conservatively for about 3 to 6 months, occasionally longer, before drilling is considered; the window is consensus rather than graded evidence. (6) In the audio: You must know that asymptomatic degenerative meniscal tears appear on imaging in up to 60% of people over age 50. — Correct: The 60 percent figure applies only to people who already have radiographic knee osteoarthritis. In the Framingham MRI cohort, 60 percent of symptom-free adults with Kellgren-Lawrence grade 2 or higher had a meniscal tear, against 23 percent of those without radiographic osteoarthritis; unconditional prevalence runs from 19 percent in women aged 50 to 59 to 56 percent in men aged 70 to 90. The lesson stands: prove the tear is the pain generator before operating. The written chapter is correct. Full correction register: https://www.reflexpmr.com/errata. The full companion chapter and a linked board-style Q-bank set for this topic are at https://www.reflexpmr.com/read/MSK-11.