I suffered a vertical patellar tendon tear in June 2014, what followed was probably the hardest 4 months of my life. My recommendations are if you can afford PRP treatments it's priceless but eccentric exercises such as 1/2 squats on a 45 degree board are just as invaluable.
I am very fortunate to have had expert physicians help me get back on track, so hopefully I can give insight to others who like me felt lost and wanted to give up.
I'm going to tell you right now this injury is 70% mental and 30% pain, once your knee has healed from surgery/injections its your onus to get back, there are no excuses and no days off. Don't get me wrong there is days I cried sitting in a car from the pain in my tendon, I barely wanted to walk outside and leave my house.
I started rehabilitation by building strength by starting off from the basic of quad strengthening by stepping on and off a box. Whilst incorporating physiotherapy with eccentric loading I was able to gradually increase loading with additional exercises such as a lot of theraband work, wall squats, leg press, and leg extension.
A standard rehabilitation day (at 11 months)
Foam Roll each muscle group 2 mins
Bicycle (5 mins) - warm up (Remember bicycle is zero times loading on your tendon, walking twice, jumping four times and running eight times)
1/2 squat on decline board @ 12kg Dumbbells
Leg Press 80kgs
Crab walks with theraband
Hamstring curls with ankle weight
VMO extension with ankle weight
Calf raise
Plank
Pelvic Floor on Swiss ball
Stretching 5-10mins
I cannot stress the importance of strengthening your sacroiliac joint, it's on the same level of importance as stretching. Don't take stretching for granted and continually utilise anti-inflammatory gel/ice. I can run at moderate pace for 20 minutes with no rest and pain, but still suffer from tenderness when pressure is placed on my knee. Eventually the pain will subside through progression of eccentric loading.