Presentation and diagnosis
This condition usually occurs because of repetitive strain, a sports injury or occupational hazard. The patient complains of pain in the line of the tendon. On examination there may be some swelling and crepitus palpated on movement of the thumb. Diagnosis is confirmed by asking the patient to make a fist while flexing the thumb into the palm and ulnar-deviating the flexed wrist. This reproduces the pain. The pain also occurs on abduction and resisted extension of the thumb.
Functional anatomy
De Quervain’s tenosynovitis affects the abductor pollicis longus and extensor pollicis brevis tendons, which have become inflamed. These tendons fuse as they cross the radial styloid and share a common synovial sheath, which forms the anterior border of the ‘snuffbox’. The tendons are lined with a synovial sheath, and in tenosynovitis the synovial surfaces become roughened, which causes pain and crepitus on movement of the tendon. The aim of the injection is to introduce the steroid, mixed with local anaesthetic, into the space between the tendon and the sheath.
Injection technique
Use 1ml steroid mixed with 1ml lidocaine 1% plain in a 2ml syringe, using a 1.6cm needle. Insert the needle along the line of the tendon just distal to the point of maximal tenderness, advancing it proximally into the substance of the tendon, when resistance to injection will be felt.
It is more painful for the patient if this injection is introduced distally.
Slowly withdraw the needle, while maintaining pressure on the plunger until the resistance disappears. At this point, the needle tip is in the tendon sheath and the whole 2ml of solution may be injected. The sheath may visibly expand along its course as the solution is injected.
You can choose any of the steroids for this purpose. Pain relief is usually dramatic and immediate.
This extract is taken from Joint and Soft Tissue Injection 5th Edition, by Dr Trevor Silver which is now available to purchase from Radcliffe Publishing.
- Confidently diagnose conditions of the joints and soft tissue.
- Understand the benefits and pitfalls of steroid injections.
- New content – sports physiotherapy, elbow joint, iliotibial band syndrome and updates on greater trochanter pain syndrome.
This book has been adapted into an interactive app, bringing to life the high-quality illustrations and diagrams. It allows you to effortlessly navigate through the detailed explanations of technique.
