CLINICAL PEARLS

It is NOT the Gastrocnemius, Soleus, or Achilles I. What Could It Be? A Plantaris Muscle Injury

Laura A. Zdziarski, LAT, ATC and Kevin R. Vincent, MD, PhD, FACSM, CAQSM

The plantaris muscle originates from the lateral supracondylar ) Relative rest, ice, compression, and elevation line of the in the posterior of the and courses ) Short-course nonsteroidal anti-inflammatory distally in an inferomedial direction near the medial head of drugs (patient dependent) the gastrocnemius and along the medial border of the Achilles & Physical Therapy . The tendon of the plantaris muscle either inserts with the or can have its own independent ) Range of motion insertion on the (4). The mechanism of injury ) Cross-training exercises to the plantaris muscle typically occurs during forceful ) Progression towards strengthening plantarflexion or when an eccentric load is experienced at the ) Prognosis for isolated plantaris muscle injury during dorsiflexion as is experienced during running or ) Return to play determined by pain and ability jumping, or merely stepping off a curb with no apparent to perform sport-specific activity trauma (Figure) (2Y4). ) Return to full activity generally within 3 to 8 wk Patient Signs and Symptoms (1,2,4,5): ) Full recovery anticipated & Posterior lower leg pain that increased over the past 24 h & Some swelling in the lower leg (not always) & Says ‘‘I felt a pop’’ or ‘‘It felt like someone kicked me in the back of my leg’’ & Depending on the severity, they may have had to cease playing & Pain with plantar flexion & Pain with resistive plantar flexion & Little to no strength loss Diagnostic Tests (3,4) & Negative Thompson Test & Ultrasound to rule out Achilles tendon pathology and document plantaris involvement & Magnetic resonance imaging to confirm plantaris involvement and/or eliminate Achilles pathology Treatment &Acute: ) Weight bearing as tolerated h Protected weight bearing: crutches or walking boot

Department of Orthopaedics and Rehabilitation, University of Florida, Gainesville, FL 32610

Address for correspondence: Kevin R. Vincent, MD, PhD, University of Florida, 3450 Hull Road, Gainesville, FL; E-mail: [email protected].

1537-890X/1402/84Y85 Current Sports Medicine Reports Copyright * 2015 by the American College of Sports Medicine Figure: Plantaris muscle.

84 Volume 14 & Number 2 & March/April 2015 Clinical Pearls

Copyright © 2015 by the American College of Sports Medicine. Unauthorized reproduction of this article is prohibited. References Plantaris_Tendon_in_a_High_School_Track_Athlete. Accessed September 1. Hamilton W, Klostermeier T, Lim EVA, Moulton JS. Surgically documented 29, 2014. rupture of the plantaris muscle: a case report and literature review. 4. Spina AA. The plantaris muscle: anatomy, injury, imaging, and treatment. J. Y Ankle Int. 1997; 18:522 3. doi:10.1177/107110079701800813. Can. Chiropr. Assoc. 2007; 51:158Y65. 2. Helms CA, Fritz RC, Garvin GJ. Plantaris muscle injury: evaluation with MR Y 5. Wiegerinck JI, Rukavina A, Made AD, et al. The calf muscle complex. In: imaging. Radiology. 1995; 195:201 3. doi:10.1148/radiology.195.1.7892469. Kerkhoffs GMMJ, Servien E, eds. Acute Muscle Injuries. Springer Interna- 3. Isolated rupture of the plantaris tendon in a high school track athlete. tional Publishing; 2014:81Y91. Available at: http://link.springer.com/chapter/ Available at: http://www.academia.edu/1406114/Isolated_Rupture_of_the_ 10.1007/978-3-319-03722-6_6. Accessed September 11, 2014.

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