Peroneal tendon subluxation

Original Editors - Tess Mertens

Top Contributors - Rachael Lowe, Tess Mertens, Maarten Cnudde and Wanda van Niekerk  

Definition/Description

Subluxation or dislocation of the peroneal tendons is a disorder involving an elongation, a tear or an avulsion of the superior peroneal retinaculum[1]. There can be also subluxation of the tendons with an intact SPR (intrasheath subluxation)[2].

Clinically Relevant Anatomy

Peroneus brevis and peroneus longus are contained in the retromalleolar sulcus on the fibula. The depth of the sulcus is variable and has been noted to be absent or convex[3] The tendons are stabilized by a superior peroneal retinaculum. The SPR is formed by thickening of the superficial aponeurosis. A small fibrous ridge is occasionally seen originating from the distal fibula close to the origin of the SPR and increases the depth of the fibular groove. Distal to the fibula is the inferior peroneal retinaculum, which covers the tendons for about 2 to 3 cm distal to the tip of the fibula[4].

Epidemiology /Etiology

The most common mechanism is a dorsiflexion force on the ankle associated with a rapid and strong contraction of the peroneal tendons and with an eversion of the hindfoot. The peroneus longus and brevis tendons sublux or dislocate from the lateral retromalleolar groove. This results from a tear or avulsion or significant laxity of the SPR. Some patients have a more chronic presentation and cannot recall a traumatic episode. Also congenital factors are reported, for example the sulcus or the ridge that helps deepen the sulcus can be too shallow or even absent or the SPR can be too loose[5]. Beyond the congenital factors, the most common mechanism is a dorsiflexory force on the ankle associated with concomitant forceful contraction of the peroneal tendons combinated with and eversion of the hindfoot[5].

Peroneal tendon subluxation is commonly encountered in skiing, but also has been reported in other sports[1][6].

Characteristics/Clinical Presentation

There are three grades to classify the acute peroneal subluxation[7][3][8]

Grade I: The retinaculum, which is confluent with the periosteum on the fibula, is stripped away from the fibula, resulting in dislocation of the tendons.

Grade II: The fibrocartilaginous ridge and the SPR is avulsed from the posterior aspect of the fibula.

Grade III: Bony avulsion of the posterolateral aspect of the fibula containing the cartilaginous rim and a flake of bone permitting the tendon to slide beneath the periosteum.

Later Oden described a fourth grade:

Grade IV: The SPR elevated from the calcaneus

  • Popping or snapping sensation on the outer edge of the ankle
  • Tendons slip out of place along the lower tip of the fibula
  • Pain, swelling or tenderness below/behind lateral malleolus
  • Painful resisted ankle eversion
  • Unstable ankle[1]

Differential Diagnosis

Examination

Acute peroneal subluxation is often difficult to appreciate clinically. There is usually oedema, ecchymosis and point tenderness in the same distribution than in case of a sprained ankle, therefore making diagnosis difficult[5].

In chronic situation patients frequently complain about a painful wind glass mechanism and can typically reproduce the dislocation by active dorsiflexion-eversion of the foot[5].   In most cases, a peroneal tendon snapping around the posterior margin of the lateral malleolus can be palpated and even visualised by the examinator. These clinical findings can be enhanced by applying a slight resistance to the dorsifl exion-eversion.

Management

In infants and neonates, conservative management of subluxing peroneal tendon is the rule and spontaneous resolution is extremely high[5],[9]. In adults the treatment can be divided into non-operative and operative when considering acute or chronic injuries[5]. When an acute subluxation is diagnosed, the patient may be consider non-operative treatment[7][3]. If the conservative treatment failed or if there’s a chronic subluxation, chirurgical treatment is probably necessary[7]. Early treatment is critical, since a tendon that continues to sublux (move out of position) is more likely to tear or rupture[10].

Conservative

In particular, non-operative treatment is indicated for grade I and possibly grade III injuries, depending on the degree of displacement of the cortical fragment[7]. Conservative treatment is associated with minimal risks but also with a high rate of failure[5].
Non operative treatment consists in applying a non weight bearing cast for 4–6 weeks[7]. This conservative management aims to allow the SPR to re-adhere to the posterolateral aspect of the fibula[5].

Conservative attempts can also include adhesive strapping with a pad to restrict subluxation, J-shaped pads that anchor in front of the fibula and wrap around laterally and posteriorly to hold the tendons in place and non-weight bearing for 4-6 weeks. If the foot is kept relatively stable and the tape restricts the tendon’s movement, scar-tissue formation may allow the tendon to be managed without surgery[11].

Surgical

Less controversy exists for the management of chronic lesions because surgical repair for peroneal tendon subluxation provides good results in most cases[5].

Surgical options[7][12]:

  • Bone block procedure
  • Reattachment of the SPR with local tissue augmentation
  • Reinforcement of the SPR with local tissue transfer
  • Rerouting the tendons behind the calcaneofibular ligament[13]
  • Groove-deepening procedures

The surgical approach may differ on the basis of the grade of injury[4].

Physical therapy after surgery

With the exception of the motion precautions, rehabilitation can proceed much like that of the chronic ankle sprain. However, the rehabilitation after surgery is likely to take more time to fully restore motion, strength and function[12]

After surgery, the ankle is maintained for 4 weeks in a non-weight bearing cast, followed by 2 weeks in a weight-bearing cast.  During immobilization, cardiovascular conditioning is performed along with proximal muscle strengthening[12].

The first few physical therapy treatments are designed to help control pain and swelling from the surgery. Ice and electrical stimulation treatments may be used. The therapist may also use massage and other hands-on treatments to ease muscle spasm and pain. Soft tissue mobilization around the scar site can be employed to increase the soft tissue mobility[11].

Treatments are also used to help improve ankle range of motion by progressive resistance and ROM excercises without putting too much strain on the area[12]. Active and resisted dorsiflexion and eversion are prevented during the early rehabilitation phase to reduce stress on the SPR (approximately 6 to 8 weeks[11].

Talar mobilization exercises and active dorsiflexion and eversion begin when the patient can bear weight without pain[11].
The progression of resisted strengthening, proprioception and agility exercises is initiated when the patient can bear weight without pain and without brace. As strength and proprioception improve, the patient can progress through plyometric and functional activities that lead to a return to competition[11].

References 

  1. 1.0 1.1 1.2 Safran MR, O'Malley D. Peroneal tendon subluxation in athletes: new exam technique, case reports, and review. Med Sci Sports Exerc. 1999; 31(Suppl 7): s487-92
  2. Raikin SM, Elias I, Nazarian LN: Intrasheath subluxation of the peroneal tendons. JBJS Am. 2008 May;90(5):992-9
  3. 3.0 3.1 3.2 Roger A. Mann, Subluxation and dislocation of the peroneal tendons. Operative Techniques in Sports Medicine, Vol 7, No 1 (January), 1999: pp 2-6
  4. 4.0 4.1 Rosenberg ZS, Bencardino J, Astion D, Schweitzer ME, Rokito A, Sheskier S: MRI Features of Chronic Injuries of the Superior Peroneal Retinaculum. AJR:181, December 2003
  5. 5.0 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 Akiki A, Crevoisier X; Peroneal Tendon Dislocation: Schweizerische Zeitschrift für «Sportmedizin und Sporttraumatologie» 55 (1), 26–29, 2007
  6. Micheo W: Musculoskeletal, Sports, and Occupational Medicine, Demos Medical New York, 272p
  7. 7.0 7.1 7.2 7.3 7.4 7.5 Heckman DS, Reddy S, Pedowitz D, Wapner KL, Parekh SG: Operative Treatment for Peroneal Tendon Disorders Review. JBJS Vol 90-A nr2 February 2008
  8. Wade R, Eckert MD, Mammoth L, Earle AD: Acute Rupture of the Peroneal Retinaculum. JBJS, 1976; 58:670-672
  9. Siegel MR, Schubiner J, Sammarco VJ: A Nonoperative Treatment Technique for Peroneal Tendon Subluxation; Clinical Pediatrics
  10. American College of Foot and Ankle Surgeons (ACFAS): http://www.footphysicians.com/footankleinfo/peroneal-tendon.htm, 12/18/2009
  11. 11.0 11.1 11.2 11.3 11.4 Starkey C, PhD, ATC, Johnson G: Athletic training and sports medicine, American Academy of Orthopaedic Surgeons, 713p, 2006
  12. 12.0 12.1 12.2 12.3 Rehabilitation in sports medicine, Paul K. Canavan, Appleton & Lange, 399p, 1998
  13. Wang C-C, Wang S-J, Lien S-B, Lin L-C; A New Peroneal Tendon Rerouting Method to Treat Recurrent Dislocation of Peroneal Tendons. The American Journal of Sports Medicine (2009) Volume: 37, Issue: 3, Pages: 552-557