Injections for pain can be a scary topic for many people. But the truth is, if you are suffering from a tendon injury, muscle tear, plantar fasciitis, bursitis, or shin splints, understanding what injections can and cannot do is an important part of making informed decisions about your care.
Types of Injections Used in Lower-Limb Rehabilitation
Corticosteroid (Cortisone) Injections
Corticosteroids are powerful anti-inflammatory agents. They work by suppressing the local inflammatory response at the injection site. In acute, reactive tendinopathy or plantar fasciitis, they can provide rapid, significant pain relief — making it easier to participate in rehabilitation exercises.
However, there are important limitations. Repeated corticosteroid injections into a tendon can weaken the collagen matrix, increasing rupture risk. For this reason, most clinicians limit Achilles tendon injections to 1–2 over a 12-month period, and avoid direct intra-tendinous injection in favour of peritendinous delivery.
Platelet-Rich Plasma (PRP)
PRP involves drawing a small amount of the patient's blood, centrifuging it to concentrate the platelets and growth factors, and injecting this concentrate into the injured tissue. The theoretical basis is sound — platelets contain growth factors that stimulate tissue repair. The clinical evidence, however, is mixed. PRP appears more effective for chronic tendinopathy than for acute presentations, and the quality of evidence supporting its use continues to evolve.
Prolotherapy
Prolotherapy involves injecting an irritant solution (typically dextrose) into the injured tissue to stimulate a localised inflammatory response, theoretically jump-starting the healing cascade. Evidence for prolotherapy in Achilles and plantar fascia conditions is growing but remains limited compared to PRP and corticosteroids.
When Injections Are Indicated
Injections are generally considered when: pain is severe enough to prevent participation in rehabilitation exercises; conservative management (load management, physiotherapy, bracing) has been consistently applied for 6–12 weeks without adequate improvement; or imaging confirms specific pathology amenable to injection (e.g. retrocalcaneal bursitis, reactive tendinopathy).
When Injections Are Not the Answer
Injections do not replace load management and progressive rehabilitation. A corticosteroid injection that provides pain relief is only valuable if that relief is used to improve rehabilitation quality and load tolerance. Without this, the underlying biomechanical drivers of the condition persist, and pain will recur when the injection effect wears off — often within 6–12 weeks.
For most lower-limb overuse conditions, the evidence consistently shows that structured physiotherapy and load management produce better long-term outcomes than injections alone. Injections are most valuable as an adjunct to, not a replacement for, structured rehabilitation.
A Note on Sever's Disease
Corticosteroid injections are generally not recommended for Sever's Disease (calcaneal apophysitis) due to the proximity of the growth plate and the paediatric population involved. Load management, bracing, and structured rehabilitation are the recommended first-line treatments.
From Pain to Performance — The Orthopaedic Sleeve Society (TOSS)