What is Greater Trochanteric Pain Syndrome (GTPS)? Anatomy and who gets it?

GTPS or lateral hip pain constitute a large number of musculoskeletal related presentations at the physician’s office¹. GTPS is an umbrella term encompassing different clinical entities that may contribute to chronic intermittent lateral hip pain. Multiple labels such as “trochanteric bursitis” and “tronchanteritis” have been used in the past which is now regarded as a misnomer². Invariably, the inflamed or enlarged bursa due to friction (sub-gluteal minimus/medius) is secondary or co-exist with an underlying pathology³. Gluteal tendinopathy is identified as one of the major culprits of GTPS along with iliotibial band (ITB) and tensor fascia lata (TFL) as potential causes³. Gluteal tendinopathy has a propensity for middle-aged women, between 40 and 60 years^{3 4}. Large number of patients fail non-operative treatment with significant levels of dysfunction making important to find novel treatment strategies⁵. Pain tends to be localized to the bony greater trochanter with aggravating activities such as walking, stair climbing and lying on the affected side¹.

MRI and ultrasound are useful imaging tools to evaluate abnormalities of the lateral hip. Most clinicians use ultrasound guidance to inject medicine around the side of the hip bony protuberance. The liquid is deposited directly on the bone, around the tendons and some into tendon itself especially for PRP injections to stimulate cascade of cellular natural inflammation and healing process.

Current treatment options for GTPS

Acute cases (<3 months) tend to be responsive to conservative measures such as physiotherapy, eccentric stretching exercises, acupuncture, shock-wave therapy, CSI and NSAID². CSI may provide benefit in the short term but with a high recurrence rate and poorer results in the long term⁵. Given the paucity of treatments for chronic gluteal tendinopathy (>3 months) and transient amelioration effect of CSI, there is interest whether biologic products such as PRP may provide better long term outcomes for this condition^{2 5}.  There is the consensus to reserve surgery only when conservative measures fail².  Systematic review by Koulischer et al (2015) pointed out that the time of onset of GTPS symptoms to surgery has declined over the years and still lack standardized surgical techniques for this condition².

New emerging treatment- PRP

The use of PRP has been controversial, especially in tendinopathies given its slower onset of action to see its efficacy. Some tendons respond differently to PRP. Technician skills, type on condition being treated and type of PRP used are all variables that can affect its effectiveness.

What is PRP?   How does it work?

Theory Behind It           

The aetiology of gluteal tendinopathy in GTPS has been proposed to be “failed healing” response. Ergo, lately ortho-biologics such as PRP has become popular in the musculoskeletal/orthopaedic community⁶. PRP is postulated to promote natural healing and provide a cocktail of high concentration cellular growth factors that mediate the regeneration tenocyte population in tendons³. Theoretically, the higher the concentration of platelets, the more growth factors will be present to promote healing at the desired area of injection⁶. PRP may often shorten rehab time and is an avenue to consider prior to considering surgery. High levels of platelets can be derived by centrifugation process of whole blood sample. FDA approved specific platelet harvesting centrifuge devices can increase the local concentration of platelets which is then injected into the target site⁷. Usually about 55 mLs of whole blood is extracted from the patient (from a vein in the elbow region) and mixed with anti-coagulant liquid in the centrifuge tube. This is then spun at high RPMs for 15- 30 mins depending on the centrifugation kit and desired PRP required by the clinician⁸. This process separate the blood components in order to discard elements not suitable (red blood cells which are heavy sink to the base), and to gather elements with therapeutic effects such as platelets, white cells, growth factors and fibrin⁸.

Common conditions treated with PRP

Common conditions treated with PRP – Lateral epicondylosis (tennis elbow), Medial epicondylosis (golfer’s elbow), Patellar tendinosis, Achilles tendinosis, Plantar fasciitis, Rotator cuff tendinosis, Gluteal tendinosis/Bursitis, Hip Labral tear, and Knee osteoarthritis.

Evidence for PRP

Below are some pragmatic studies done for the efficacy of PRP and other treatment modalities in GTPS.  We encourage you to read this before making your decision:

Benefits and potential Side effects

PRP is an autologous preparation, thus inherently safe, free from allergenic and transmissible infection⁷.

This makes the procedure safe and easily reproducible. Moreover, PRP injection also carries less chance for infection than an incision, with a considerably shorter recovery time than after surgery. Previous studies have only identified transient post injection soreness as a potential side effect.

Accessibility and cost in NZ- who offers it?

PRP is often done by Musculoskeletal Medicine or Orthopaedic specialists within the private healthcare system. Some insurance companies might fund part of the procedure cost. A referral letter is required from your General Practitioner to the specialist service. The cost may vary from $500 to 750$ per injection depending on the type of PRP used and preparation process. Up to 2-3 injections maybe required to achieve maximal benefit depending on clinical response.

What to expect on the day of procedure?

After a consultation, if appropriate, the procedure can be done under ultrasound guidance in the clinician’s rooms, or in a local radiology suite. It is advised to wear loose clothing to allow adequate exposure of the injection site. Any anti-inflammatory or aspirin should be stopped one week before and four weeks after. Please check with your family doctor prior to stopping your aspirin.

Post- PRP injection Care:

1. Pain- You might feel like a “bruise’ feeling 24-48 hours post-injection. Please call your doctor if you notice any numbness, redness, discharge, or fever.
2. Driving- Depending on the area injected (e.g. heel/hip/knee), you might need someone to accompany you to drive you home after the injection.
3. Activity- You should avoid strenuous activity for the first 48 hours.
4. Work- Depending on the work you do; you might only need one day off on the day of the procedure.
5. Follow up appointment- usually will be informed by your doctor/specialist.
6. Concerns- call your family doctor or physician’s office who administered the PRP injection.

Post- PRP injection Rehab Protocol:

Note: This regimen might vary depending on degree on pathology, patient response and physician advice.

Should I go for it?

The role of PRP in GTPS is open for debate. Nevertheless, some studies show promising results in the long term compared to corticosteroid injection and is a reasonable option if other conservative measures have failed.