Patient Population:

Patellar or Achilles tendinopathy. RCTs and CCTs comparing loading programs: participants mean age was 27 years and 77% were male.  All were active in sports.

Intervention:

Eccentric, eccentric-concentric and isolated concentric muscle loading programs for the treatment of patellar tendinopathy. 6/10 patellar tendon studies examined the use of isolated eccentric loading programs in at least one of the designated treatment groups. 2 patellar studies used the eccentric-concentric loading model. 2 patellar studies investigated “heavy-slow resistance” (HSR) (slow double leg isotonic eccentric-concentric contractions).

Comparison:

There were 33 studies identified that either compared two loading programs or evaluated at least one non-clinical outcome (potential mechanism associated with loading programs).  Mean quality assessment was reported as a percentage of the possible total score – 54% (range 26-83%).  Studies scoring <40% were not included in the analysis (n=5).  Eleven (11) of the studies included examined patellar loading, though one of these also included Achilles tendon loading as well.

Outcome:

1. Comparison of Loading Programs:  6 RCTs or CCTs compared loading programs used in the treatment of patellar tendinopathy.  These were all small studies with a total of 112 participants.  Based on the results of 2 high-quality studies, they conclude that there is moderate evidence that HSR and eccentric loading provide similar results in terms of pain/function (VISA), but patient satisfaction is higher post HSR. There was also limited evidence (3 low-quality studies) that clinical outcomes associated with eccentric loading may be superior to those associated with Stanish and Curwin loading or concentric loading (although Standish and Curwin may be superior to isotonic). The use of a decline board may also be associated with additional benefit in programs of eccentric loading (limited evidence – 1 very low quality study).

2. Eccentric Loading: (2 high-quality studies) Moderate evidence of improved clinical outcomes associated with increased knee extensor torque, increased leg press L-repetition maximum and increased quadriceps muscle CSA.  There is conflicting evidence regarding the association between jump performance and clinical outcome.

3. HSR Loading: (2 high-quality studies) Strong evidence of improved clinical outcome associated with increased knee extensor torque.  Moderate evidence (1 high quality study) that improved outcomes are associated with increased quad muscle CSA.

4. Stanish and Curwin: (1 low-quality study) Limited evidence that improved clinical outcomes are associated with increased knee flexor (not extensor) torque.

5. Other: There is limited evidence that torque deficits may resolve post-isokinetic loading (low quality study) and improved outcomes are associated with increased eccentric force on a flywheel device (one low quality study).