BACKGROUND: Dislocation or subluxation of the peroneal tendons out
of the peroneal groove under a torn or avulsed superior peroneal retinaculum
has been well described. We identified a new subgroup of patients with
intrasheath subluxation of these tendons within the peroneal groove and with
an otherwise intact retinaculum.
METHODS: The cases of fifty-seven patients with painful snapping of
the peroneal tendons posterior to the fibula were reviewed. Of these,
forty-three had tendons that could be reproducibly subluxated out of the
groove with a dorsiflexion-eversion maneuver of the ankle. Fourteen patients
who could not subluxate the tendons out of the groove underwent a dynamic
ultrasound examination of the tendons. While the same dorsiflexion and
eversion maneuver was being performed, the tendons were seen to switch their
relative positions (the peroneus longus came to lie deep to the peroneus
brevis tendon) with a reproducible painful click. All fourteen patients
underwent a peroneal groove-deepening procedure with retinacular reefing.
Intraoperatively, thirteen patients were found to have a convex peroneal
groove and all fourteen had an intact peroneal retinaculum. All patients
subsequently underwent a follow-up dynamic ultrasound examination and an
American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score
evaluation at a minimum of twenty-four months after surgery.
RESULTS: All fourteen patients were female, with an average age of
thirty-five years. Two subtypes of intrasheath subluxation were found. Type A
(ten patients) involved intact tendons with relative switching of their
anatomic alignment. Type B (four patients) involved a longitudinal split
within the peroneus brevis tendon through which the longus tendon subluxated.
Intraoperative confirmation of the ultrasound findings was 100%. At an average
follow-up interval of thirty-three months, the average AOFAS score had
improved from 61 points preoperatively to 93 points, and the average score on
the 10-cm visual analog pain scale had improved from 6.8 to 1.2. Follow-up
ultrasound evaluation revealed healed tendons without persistent subluxation
in thirteen patients. Nine patients rated the result as excellent, four rated
it as good, and one rated it as fair.
CONCLUSIONS: Patients with retrofibular pain and clicking of the
peroneal tendons may not have demonstrable subluxation on physical examination
and may have an intact superior peroneal retinaculum. They may have an
intrasheath subluxation of the peroneal tendons, which can be confirmed with
use of a dynamic ultrasound. Surgical repair of tendon tears combined with a
peroneal groove-deepening procedure with retinacular reefing is a reproducibly
effective procedure for this condition.
LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions
to Authors for a complete description of levels of evidence.