Ankle injury: normal findings are still helpful.
A 27-year-old woman presented having suffered an injury to her left ankle. Approximately a week earlier she had been out running and had hurt her ankle, which was tender both medially and laterally. An X-ray did not show a fracture, and she was advised to wear a moonboot. Ultrasound examination (Philips iU22, L12-5 MHz and 15-7 MHz Hockey Stick transducers) of the lateral, medial, anterior and posterior compartments of her left ankle was performed.
The examination suggested a normal ankle examination.
Key findings (Figures below) included confirmation of tenderness at the medial aspect of the ankle, but with no abnormality seen. The anterior inferior tibiofibular ligament (AITFL), posterior inferior tibiofibular ligament (PITFL), posterior talofibular ligament (PTFL), anterior talofibular ligament (ATFL), calcaneofibular ligament (CFL), dorsal talonavicular ligament (DTNL), bifurcate and deltoid ligaments were all normal. Additionally, the peroneus longus and brevis, tibialis posterior and anterior, extensor hallucis longus (EHL), extensor digitorum longus (EDL), flexor digitorum longus (FDL) and flexor hallucis longus FHL tendons were normal. There was no joint effusion seen.
It is perhaps tempting to endorse an argument that immobilisation for this patient was not necessary, and functional rehabilitation was more closely indicated. Conversely, it is equally reasonable to suggest that immobilisation was useful given the unclear diagnosis in this case. In fact, both of these approaches appear reasonable1 and perhaps ideal might be early activation of joint stabilisers with some splinting to support mobilisation.2 Regardless of the decision ultimately made regarding management of a patient such as this one, we think that early and accurate diagnosis can inform the basis of the therapeutic reasoning process.
The use of medical imaging as a diagnostic tool in musculoskeletal medicine is a somewhat controversial topic; overuse, underuse and misuse have all been cited as problematic.3 In particular, there has been a rise in popularity of MRI and CT despite their cost.4 Diagnostic ultrasound is a non-ionizing tool that is comparatively cheap, easy to access, and has been demonstrated to be accurate in diverse body regions5, including the ankle.6 Findings indicating minor or trivial injury such as in this case may be just as helpful as those demonstrating more profound injury, when it comes to electing the most appropriate rehabilitation strategy for the patient.
Coming in the next post:
A diagnosis of a complex foot injury. What might the clinical presentation be?
- Kerkhoffs GM, Rowe BH, Assendelft WJ, Kelly KD, Struijs PA, van Dijk CN. Immobilisation for acute ankle sprain. A systematic review. Arch Orthop Trauma Surg. 2001 Sep;121(8):462–71.
- Bleakley CM, O’Connor SR, Tully MA, Rocke LG, Macauley DC, Bradbury I, et al. Effect of accelerated rehabilitation on function after ankle sprain: randomisedcontrolled trial. BMJ. 2010 May;340:c1964.
- Bussières AE, Peterson C, Taylor JAM. Diagnostic imaging practice guidelines for musculoskeletal complaints in adults–anevidence-based approach: introduction. J Manipulative Physiol Ther. 2007;30(9):617–83.
- Smith-Bindman R, Miglioretti DL, Larson EB. Rising use of diagnostic medical imaging in a large integrated health system. Health Aff (Millwood). 2008;27(6):1491–502.
- Henderson REA, Walker BF, Young KJ. The accuracy of diagnostic ultrasound imaging for musculoskeletal soft tissuepathology of the extremities: a comprehensive review of the literature. Chiropr Man Therap. 2015;23:31.
- Cao S, Wang C, Ma X, Wang X, Huang J, Zhang C. Imaging diagnosis for chronic lateral ankle ligament injury: a systemic review withmeta-analysis. J Orthop Surg Res. 2018 May;13(1):122.