Accurate diagnosis is very important, and can most commonly be diagnosed with pain localised to the inferior aspect of the patella, and is seen mainly in the younger caseload who participate in sports which require repetitive loading, especially in energy storage and release (plyometric) type forces through the tendon.
Rehabilitation from these can be broken down into 4 main stages when returning to full recovery. 1. Isometric loading- This should only be used if the patient reports more than 3-4/10 on the visual analogue pain scale (VAS) for isotonic loading. Try 5 sets of 45 seconds 2-3 times each day and progress up to 70% of max contraction as pain allows. Using a leg extension machine or Spanish squats held at between 30 and 60 degrees flexion at the knee can be a good method of delivery, as they target the quadriceps specifically in the mid-range which tends to be less irritable 2. Isotonic Loading- Progressed when there is minimal pain during isometric exercise. Try 3-4 sets beginning at 15RM and increasing load up to 6RM, repeating every second day. Ensure pain is kept below 3-4/10 VAS. Eccentric exercise has typically been used for this stage, but heavy slow resistance exercises (HSR) have similar outcomes at 6 months but which much better compliance and patient satisfaction than eccentric loading as it can feel more functional. Try leg single leg press, lunges with upright fore-foot tibia. 3. Energy-storage loading (Plyometric)- This can only be tried if patient starts to reach similar strength on both legs, and again has 3-4/10 VAS maximum, and returns to baseline within 24hours. Gradually increase the functionality of the exercise to replicate demands of the relevant sport that the patient is looking to return to. Try simple tasks like jumping double to single as tolerated and progress to acceleration then deceleration and finally cutting drills. 4. Return to sport- Only to be progressed once patient can tolerate plyometric forces consistently when replicating the same stresses that will be placed on in their sport. Start with full training and ensure tolerance before returning to competitive.