Treatment of Chronic Patellar Tendinopathy with Autologous Bone Marrow Stem Cells: A 5-Year-Followup

Table 1

Sonographic grading of the patellar tendinopathy. Grade ratio between injured area and whole tendon section at US scan.

Grade
1	Injured area is less than 20% of the whole tendon section
2	Injured area is between 20% and 50% of the whole tendon section
3	Injured area is more than 50% of the whole tendon section
4	Subtotal or total tear, respectively, with partial and total tendon retraction