High-Volume Image-Guided Injections in Achilles and Patellar Tendinopathy in a Young Active Military Population: A Double-Blind Randomized Controlled Trial
This one peaked my interest. Often, we hear stories and get told ‘never injection a tendon’ as podiatrists. This was defiantly my experience at the university and new graduate level. I don’t know if anyone else has had that. I work in an environment where injectables are a daily and consistent treatment (with Sports Doctors). I see and hear of great results. People that have an injection every 1,5 or 10 years with only positive reported effect. In most cases, people are having this injection in combination with other loading protocols and doing all the right things.
Achilles and patellar tendinopathy are prevalent conditions among populations exposed to frequent mechanical loading. They typically take a long time to get better, with some studies showing up to 40% of people have continuing symptoms 5 years later. Best practice management has progressive loading within a pain monitoring framework at its core.
So what happened, what did they do and why?
What is the efficacy of HVIGI with and without steroid relative to placebo?
A total of 62 participants. Participants were men (would like to see women in these studies) aged 18 to 55 years with Achilles or patellar tendinopathy of at least 6-month chronicity that had not improved with nonoperative management (including physical therapy and shockwave therapy), with ultrasound evidence of neovascularization, tendon thickening, and echogenic changes. Great to see this happening after other treatments had been tried. Seems relevant for most clinicians.
They were randomly assigned to the following groups:
Low-volume (3 mL) peritendinous local anesthetic (control group): 0.5% bupivacaine (3 mL = 15 mg)
HVIGI group: 0.5% bupivacaine (10 mL = 50 mg) + 30 mL of saline
HVIGI with Steroid group: 0.5% bupivacaine (10 mL = 50 mg) + 100 mg/mL of hydrocortisone (0.25 mL = 25 mg) + 29.75 mL of saline
Clinicians and assessors were blinded.
All participants were supervised through a pain-guided progressive loading program for 6 months post injection. This does make things somewhat more difficult to draw conclusions from, however, this would be what most people would recommend anyway. Not often, treatments are done in isolation. The main outcome measures were the Victoria Institute of Sport Assessments (VISA) for Achilles and patellar tendinopathy and the visual analogue scale (VAS) for pain at 6 months post injection.
Why cortisone and how?
High-volume image-guided injection (HVIGI) is proposed to target the neovascularity visible on ultrasound Doppler. Using mechanical stripping and potential toxicity from local aesthetic, HVIGI is proposed to reduce hypersensitive substance P–positive nerve fibers. A higher volume of at least 50 mL has been shown to be more effective than a lower volume of around 30 mL in consecutive case series
Where did they inject?
Under ultrasound guidance, a 21-gauge needle was placed between the anterior aspect of the Achilles tendon and Kager's fat pad or posterior aspect of the patellar tendon and Hoffa's fat pad at the area of maximum neovascularization (often associated with the greatest anterior-posterior diameter) (Figure 1A). Connecting tubing attached using a Luer lock (Becton Dickinson, Sweden) to a 10-mL syringe was then connected to the needle. Under instruction of the consultant, the assistant then delivered the contents of the syringe to separate the fat pad from the tendon.
All participants were advised to continue with a pain-guided progressive loading program. All participants were progressed along an incremental pathway of rest (initially 5 days); isometric (phase 1), isotonic (phase 2), and heavy slow (phase 3) resistance; and then elastic activities including plyometrics and return to running (phase 4) according to symptoms. A logbook was issued to all participants for them to record activity and compliance. A target score ≤30 of 100 was used for pain during prescribed loading. The same target score (≤30/100) was not to be exceeded for resting pain the following day to avoid continual overload and net collagen degradation.
Conclusion and thoughts?
The results of this double-blind RCT showed that neither an HVIGI with nor one without steroid resulted in significant differences in pain and function outcome measures at the 6-month follow-up compared with a sham-control injection. The lack of group differences across both studies, conducted using similar methods, in conjunction with the success of the control group in the current study, supports the use of pain-guided progressive loading as the mainstay of treatment. Taken together in the medium to long term, the control of pain levels in tendinopathy is a priority, but careful load prescription rather than injectable therapy may result in more enduring improvements.