Notes and Illustrations
Children and adolescents 10-14 years
Knee pain aggravated by activity
Tenderness and soft tissue swelling over the inferior pole of the patella.
Probably traumatic (traction injury) origin
Closely related to Osgood-Schlatters
Tendinitis, followed by calcification or ossification.
X-ray - osseous fragmentation at lower pole patella
NOT an apophysitis or osteochondritis.
Patellar fracture or avulsion infrequent.
The calcifications are usually incorporated into the inferior pole of the patella, and the natural course of the condition is 3-12 months.
No need follow up x-ray in most
Treated symptomatically
Also responds to quads strengthening exercises
Rarely, debridement of patellar tendon needed

JBJS A 60-A #8 1113 (1978) Full Text
In a prospective study of children with pain in the knee, eight patients (ten knees) were seen with the clinical and roentgenographic findings of Sinding-Larsen-Johansson disease. The etiology appears to be a traction tendinitis with de novo calcification in the proximal attachment of the patellar tendon, which had been partially avulsed. The patients were followed through the course of the disease, which was found to be self-limited and benign like Osgood-Schlatter disease.

Google search string allintitle: site:www.ncbi.nlm.nih.gov Sinding-Larsen-Johansson
Note this is not a comprehensive PubMed Search and only looks for SLJ in the title

TIBIA VARA Alternative titles; symbols BLOUNT DISEASE OSTEOCHONDROSIS DEFORMANS TIBIAE TEXT Little is known about this condition which bears some similarity to osteochondritis of various sites (165800) and which may be heterogeneous. Blount (1937) suggested the existence of an infantile type with onset in the first year or two of life and an adolescent type developing just before puberty. The report by Blount (1937) concerned 22 cases of bowlegs in infants, with progressive deformity and radiologic findings of sloping proximal tibial epiphysis and a medial beak of the metaphysis. The description by Tobin (1957) of tibia vara beginning at puberty with osteochondritis dissecans of the knees in father and 2 sons strengthens the view that the 2 disorders are fundamentally identical.