- See:
Peroneus Longus /
Peroneus Brevis:
- Discussion:
- acute dislocation occurs by sudden forced dorsiflexion w/ concomitant eccentric contraction of the peroneal muscles;
- classic teaching that the tendon dislocation occurs from a combination of dorsiflexion and eversion (like skiing), where as other authors feel
that the injury occurs from dorsiflexion and inversion (which accounts for its association with ankle instability);
- chronic peroneal tendon dislocation is often associated w/ recurrent
ankle sprains, which lead to incompetency of peroneal retinaculum, and
subsequent tendon subluxation;
-
patho-anatomy:
- at the level of the ankle joint, the peroneal tendons lie in a groove in the posterior fibula;
- grove is present in (82%) fibulas, a transverse flat surface in 19 (11%), and a convex surface in 13 (7%);
- average width of sulcus, when present, is 6 mm;
- lateral border of the posterior fibular surface may form a bony ridge (2-4 mm) augmenting the sulcus;
- peroneus longus courses posterior to the brevis tendon, and then both tendons pass thru the common peroneal
synovial sheath, about 4 cm proximal to the lateral malleolus;
- synovial sheath passess through a fibro-osseous tunnel that is stabilized by the superior peroneal retinaculum and by calcaneofibular ligament;
-
superior peroneal retinaculum:
- primary constraint to peroneal tendon subluxation;
- retinaculum is formed as a confluence of superficial fascia, and sheath of peroneal tendons, and periosteum of distal fibula (about 2 cm proximal to fibula tip);
- formed from thickening of fascia that arises off the posterior margin of distal 1-2 cm of the fibula and runs posteriorly to blend with the Achilles tendon sheath.
- synovial sheath passes behind the distal fibula (retromalleolar sulcus), and the depth of the sulcus may be related to propensity for peroneal subluxation;
- w/ peroneal tendon dislocation there is stripping of the periosteum from the lateral malleolus which is in continuity w/ superior peroneal retinaculum;
- result is the creation of a false pouch posteriorly (similar to the false pouch created by a shoulder Bankhart lesion);
-
associated findings:
-
anterolateral instability of the ankle is associated with laxity of the superior peroneal retinaculum;
- superior peroneal retinaculum is a secondary constraint to anterolateral ankle instability;
- degenrative changes and longitudinal splitting in the peroneus brevis tendon;
- Exam:
- there will be tenderness posterior to the lateral malleolus;
- subluxation of the peroneal tendons may be provoked by having the patient dorsiflex the foot from a position of dorsiflexion and eversion;
- look for a prominence of the tendon w/ dorsiflexion and internal rotation;
- w/ chronic peroneal tendon subluxation, there will often be signs of ankle instability;
- w/ a questionable exam, consider a diagnostic lidocaine injection into the peroneal tendon sheath;
Imaging:
- need to assess mortise view of the ankle;
- look for shell-like avulsion fracture of the lateral malleolus (which indicates disruption of the peroneal retinaculum) and dislocation of the peroneal tendons;
- Tenograms and CT may be used, but MRI is of greatest value in evaluating soft tissue structures
- Non Operative Treatment:
- ensure that the tendons are reduced before immobilization;
- place in plantar flexion in slightly inverted below knee cast for 6 wks
- note that conservative treatment for acute injuries in active young athletes, generally has a relatively high recurrence rate (50%);
- Surgical Treatment:
- in active patients, surgical fixation of the disrupted sheath is treatment of choice.
- Surgical Options: peroneal groove deepening, tenoplasty, or bone block;
*- Groove Deepening with SPR repair
- if performed with care can preserve the periosteal flaps and help secure tendon sheath to posterior fibula
- Kolias and Ferkel (Am J Sports Med 1997) 95% success rate
- Mendicino et al (J Foot & Ankle Surg 2001) 100% success rate
- Surgical Technique: (Click on picture to the right to view movie of this procedure)
- osteotomize distal posterior fibula leaving medial side hinged
- curette underlying cancellous bone
- reinsert flap into deepened bed
- Advantages
- correct groove deficiency
- maintain cartilaginous gliding layer
- rare recurrence, all reinforced SPR simultaneously
- Disadvantages
- tendon irritation on bony edges, failure to correct dislocation pouch
- tenodesis should be performed 3-4 cm above the fibular tip and 5-6 cm below the fibular tip;
- in the Singapore operation, the false pouch is obliterated by suturing down the superior retinaculum to the posterior fibula;
- a secure repair, requires drill holes to be made in the distal fibula;
- in some cases, a slip of Achilles tendon may be required to augment the repair;
- hazards: note that the sural nerve lies about 1 cm distal to the distal end of the fibula;
Tendon injuries about the ankle resulting from skiing.
Static or dynamic repair of chronic lateral ankle instability. A prospective randomized study.
Recurrent dislocation of the peroneal tendon.
Traumatic dislocations of the peroneal tendons. Arrowsmith SR, Fleming LL, Allman FL: Am J Sports Med 1983;11:142.
Acute rupture of the peroneal retinaculum. Eckert WR, Davis EA: J Bone Joint Surg 1976;58A:670-673.
Dislocation of the peroneal tendons long term surgical treatment. Escalas F, Figueras JM, Merino JA: J Bone Joint Surg 1980;62A:451-453.
Dislocation of the peroneal tendons. Marti R: Am J Sports Med 1977;5:19-22.
Sliding fibular graft repair for chronic dislocation of the peroneal tendons. Micheli LJ, Waters PM, Sanders DP: Am J Sports Med 1989;17:68-71.
Ankle injuries in skiing. RE Leach and G Lower. CORR. Vol 198. 1985. p 127-133.
Peroneal tendon injuries. HD Clarke MD et al. Foot and Ankle Internation. Vol 19. No 5. May 1998. p 281.
Traumatic Peroneal Tendon Instability Rhett B. Mason and Ian J. P. Henderson. American Journal of Sports Medicine. Vol 24 No 5 Sep - October 1996
Superior peroneal retinaculoplasty: a surgical technique for peroneal subluxation.
Current Concepts Review: Peroneal Tendon Subluxation and Dislocation
