Spontaneous osteonecrosis of the knee (SONK) is a condition that tends to arrive without warning. One day you are walking, cycling, or climbing stairs without much thought, and then comes a sharp, localized pain — often in the medial femoral condyle — that does not resolve the way a muscle strain would.

If you have been told you have a bipartite patella, you've likely received one of two responses: "it's usually nothing" or "we'll manage the pain." Neither answer is particularly satisfying if your knee keeps flaring up during sport, after a long walk, or simply climbing stairs.

If you are dealing with a coronary ligament sprain, you are probably familiar with the frustrating pattern: pain along the knee joint line, sometimes present with every step, sometimes triggered only by squatting or rotating.

If you have pes anserine tendinopathy, you are probably already familiar with the standard advice: rest, ice, anti-inflammatory medication, maybe a corticosteroid injection if things get bad enough. You may have been told to lose weight, stretch your hamstrings, or strengthen your quadriceps.