PRP Injections and Tendinopathy
Tendinopathy is a significant cause of morbidity in Australia, and accounts for around 20% of musculoskeletal complaints. Tendinopathy is defined as tendon degeneration without clinical or microscopic signs of inflammation. It is typically found to be an overuse problem, and can affect any tendon, the more common ones including:
- Achilles tendinopathy
- Patellar tendinopathy
- Rotator cuff tendinopathy in the shoulder
- Tennis and Golfer’s elbow; and
- Gluteus Medius tendinopathy of the hip, also known as trochanteric bursitis.
Sports Medicine studies have resulted in a dramatically different treatment approach to that previously used of prolonged periods of rest and high doses of anti-inflammatory medication. Rather, the preferred approach now is to encourage the tendon to strengthen and remodel through a graded strengthening programme, whilst also avoiding aggravating activities.
Unfortunately, and for a number of reasons such as poor blood supply, and the relatively small number of tendon cells present, tendon healing is slow, and is thought to be 5-6 times slower than muscle. This has lead to the search for agents which can enhance or speed up the healing process in tendons and other tissues, to achieve functional strength in the tendon earlier and return the athlete to sport and activity.
Platelet-rich Plasma (PRP) Injections
Platelet-rich Plasma (PRP) refers to the concentration of growth factors and other mediators retrieved after ‘spinning down’ blood taken from the patient. PRP has been used clinically in humans for its healing properties attributed to the increased concentrations of growth factors and proteins that may enhance the healing process on a cellular level. The hope is the PRP enhances the recruitment, proliferation and differentiation of cells involved in tissue regeneration.
There have been numerous promising basic science studies, animal studies and small case reports regarding PRP. Detailed and thorough scientific studies are currently underway, in the hope of confirming a definite benefit from the use of PRP. PRP has been used to enhance the healing of meniscus defects and muscle injuries; to stimulate chondrocytes to engineer hyaline cartilage; to improve outcomes after joint replacement and subacromial decompression; to improve the outcome of operated Achilles tendons; to reduce pain in chronic tendinopathies, and to prevent intervertebral disc degeneration
PRP is prepared from blood taken from the patient, and which is centrifuged to concentrate platelets in plasma. The intention is to augment the native healing process at the site of pain through the action of growth factors, and jumpstart healing in chronic injuries, or speed up an acute injury repair process.
Adverse Effects and Advice Post-Injection
Some patients will mount a significant inflammatory response post injection. Patients are instructed to ice regularly, elevate or rest limb for 24-48hrs if painful. Panadol or codeine can be used if needed. Anti-inflammatories should not to be used for first two weeks, as they may inhibit the inflammatory healing cascade and thus the beneficial effects stimulated by the PRP injection.
There should be one week of restricted activity; one week of stretching exercises, followed by a progressive eccentric strengthening programme, progressing onto sports specific activities once appropriate strength achieved.