Peroneal Tendon Tear 726.79

synonyms: peroneal tendon tear, peroneal tendon disruption

Peroneal Tendon Tear ICD-9

• Peroneal tendinitis ICD-9 = 726.79

Peroneal Tendon Tear Etiology / Epidemiology / Natural History

Peroneal Tendon Tear Anatomy

• Superior peroneal retinaculum: primary retaining structure for the perneal tendons. Origin: posterior margin of the distal 1-2cm of the fibula. Travels posteriorly to the lateral calcaneus with extensions into the paratenon of the Achilles tendon. Most commonly avulses from the fibula often with a small fleck of bone.  (Maffuli N, AJSM 2006;34:986).
• Deficient posterior distal fibular groove may contibute to peroneal instability.  Approximately 25% of people have a flattened or convex peroneal groove.
• Hindfoot varus alignment is a predisposition to peroneal tendon injury.
• Os peroneum is a sesamoid bone present in 10% to 20% of people located along the peroneus longus near the peroneal groove of the cuboid. (Sobel M, Foot Ankle Int 1994;15:112)
• Anatomic varients in peroneal tendon sheath: low-lying peroneal brevis muscle belly; anomalous peroneal quartus tendon.

Peroneal Tendon Tear Clinical Evaluation

• Lateral ankle pain, swelling and ecchymosis.
• Tenderness posterioly along the peroneal tendons.
• Pain and weakness with active ankle dorsiflexion and external rotation.
• Lateral tenderness, no medial tenderness.
• Ankle Circumduction Test: indicates peroneal tendon instability

Peroneal Tendon Tear Xray / Diagnositc Tests

• A/P, Lateral and Mortise views of the ankle are normal.  May demonstrate a "fleck" sign: small avulsion fracture of the lateral malleolus which is pathognomonic for acute dislocation of the peroneal tendons and indicates Grade III injury to the superior peroneal retinaculum.
• MRI: demonstrates disruption of the peroneus brevis +/- peroneus longus. Partial thickness tears will demonstrate fluid accumulation (high intensity signal) within the tendon
• Dynamic ultrasound: may be indicated to evaluated for pseudosubluxation of the peroneal tendons. (Grant TH, JBJS 2005;87A:1788).

Peroneal Tendon Tear Classification / Treatment

• Acute Partial Thickness Peroneous brevis tear: brief period of immobilization followed by focused physical therapy to maintain ROM, strengthen and restore proprioception. May return to sports in ankles taped / athletic ankle brace when pain is minimal and full motion and strength have been restored.
• Chronic unrepairable peroneus brevis/longus tears with lack of foot eversion: FDL transfer (Wapner KL, Foot Ankle Int 2006;27:591)  Other options: VDL transfer or autograft/allograft tendon repair. 

Peroneal Tendon Tear Associated Injuries / Differential Diagnosis

• PER ankle fracture (Weber type C)
• SER ankle fracture (Weber type B)
• Proximal fibula fx (Maisonneuve).
• Ankle dislocation.
• Peroneal Tendon Instability
• 5th Metatarsal fracture
• Calcaneal fracture
• Ankle Tear
• Peroneal Tendon Instability

Peroneal Tendon Tear Complications

• Recurrent Tear
• Continued pain
• Stiffness
• CRPS

Peroneal Tendon Tear Follow-up Care

• Outcomes of peroneal tendon tear operative treatment:  90% return to employment at the same level. 58% scar tenderness; 54% lateral ankle swelling; 46% successfully return to sports.(Steel MW, Foot Ankle Int 2007;28:49)

Peroneal Tendon Tear Review References