Wide-Awake Tenolysis for Tendon Entrapment in a Distal Radial Epiphyseal Separation (Volar Displacement Type): A Case Report

Abstract

The patient was a 13-year-old male who fell while riding a bicycle and was initially diagnosed with a distal radial epiphyseal separation (volar displacement type) that was conservatively managed. Four months post-injury, he complained of limited movement in his left index finger and was referred to our hospital. Upon examination, the patient also complained of limited movement of the left index finger in wrist flexion. The wrist range of motion was 50° of volar flexion, 50° of dorsiflexion, 90° of pronation, and 90° of supination with the fingers extended. The X-ray revealed a radiolucent area in the distal radius. Ultrasound, computed tomography, and magnetic resonance imaging scans demonstrated entrapment of the extensor tendon within the medullary cavity of the radius. Five months post-injury, surgery was performed using the wide-awake local anesthesia no-tourniquet (WALANT) technique. A dorsal wrist approach was utilized, and the extensor digitorum communis tendon was found to be trapped within the medullary cavity of the radius. The tendon was released using an air drill, and sufficient improvement in the left index finger flexion was confirmed with active movement before concluding the surgery. At the 11-month postoperative follow-up, the patient showed excellent outcomes with a wrist range of motion of 75° of volar flexion, 85° of dorsiflexion, 90° of pronation, and 90° of supination. Tendon entrapment of the extensor tendons has been reported as a long-standing complication associated with distal radius fractures, particularly with volar displacement types. A benefit of the WALANT technique is the ability to communicate with the patient during surgery, allowing for active movements of the fingers and wrist. This is particularly useful in tendon surgeries for determining tendon tension. We report a case of successful tenolysis surgery using the WALANT technique for a patient with a conservatively managed distal radial epiphyseal separation (volar displacement type), who experienced a limited flexion of the index finger due to tendon entrapment.

Keywords: distal radial epiphyseal separation; extensor digitorum communis tendon; tendon entrapment; volar displacement type; walant technique.

Figure 1. X-ray at the time of injury (yellow arrow)

Figure 2. X-rays after manual reduction and immobilization (yellow arrow)

Figure 3. Limited flexion of the index finger in wrist flexion (yellow arrow)

Figure 4. X-ray showing a radiolucent area in the distal radius (red box)

Figure 5. Computed tomography scans (sagittal view) showing a radiolucent area in the distal radius (yellow arrow)

Sagittal view: from A to E, ulnar to radial

Figure 6. Ultrasound of the wrist showing EDC entrapment within the medullary cavity of the radius

A: Normal. B: EDC entrapment within the medullary cavity of the radius (yellow arrow). EDC, extensor digitorum communis

Figure 7. Magnetic resonance imaging scans showing EDC entrapment within the medullary cavity of the radius (yellow arrow)

From A to D, cranial to caudal. EDC, extensor digitorum communis

Figure 8. Extensor tendon tenolysis performed (four months post-injury)

A: preoperative. B: postoperative.

Figure 9. Surgery performed using the WALANT technique, confirming improvement in the index finger flexion with intraoperative active movement

A: finger extension. B: finger flexion. C: wrist dorsiflexion. D: wrist volar flexion.

Figure 10. Wrist range of motion at 11 months post-operation

A: 75°of volar flexion. B: 85°of dorsiflexion. C: 90°of supination. D: 90°of pronation (yellow arrow: injured side)

Figure 11. No recurrence of the limited index finger flexion at 11 months post-operation

A: finger flexion. B: finger extension.

Figure 12. A. Normal. B. At the time of injury. C. Tendon entrapment after reduction

The image was created by Ken Yamamoto.