Peroneus Brevis Tendon Variant Insertion on the Calcaneus

Direct Observation of a Single Peroneal Myotendinous Unit Anatomic Variant: A Case Report and Systematic Review

CASE

A 29-year-old woman with acute peroneal tendon subluxation underwent superior retinacular repair. On exposure, a single peroneal myotendinous unit was encountered, as opposed to the usual presence of independent peroneal tendons arising from separate muscle bellies. At 3-year follow-up, she has had no recurrence with full return to activity and no limitations.

CONCLUSION

Multiple peroneal myotendinous variants have been described; however, this report is the first to describe direct intraoperative observation of a single peroneal myotendinous unit. Whether this anatomic variant contributed to the patient's problem or has other potential clinical sequelae remains to be elucidated.

Endoscopic Resection of Peroneus Quartus

The peroneus quartus is the most common supernumerary muscle of the foot and ankle. It can be symptomatic and associated with splits or tears in the peroneus brevis, subluxation or dislocation of the peroneal tendon, tendinous calcification, chronic peroneal compartment syndrome, and painful hypertrophy of the retrotrochlear eminence. The purpose of this Technical Note was to describe the details of endoscopic resection of the peroneus quartus. This technique has the advantages of better cosmetic results, less pain, less surgical trauma, and the possibility of dealing with associated pathologies endoscopically.

Anatomical variations related to pathological conditions of the peroneal tendon: evaluation of ankle MRI with a 3D SPACE sequence in symptomatic patients

OBJECTIVE

To evaluate anatomical variations in the lateral ankle and their relationships with pathological conditions of the peroneal tendon on magnetic resonance imaging (MRI) in symptomatic patients.

MATERIALS AND METHODS

Sixty-nine ankles MRIs of 60 adult patients with symptomatic ankles were included. The presence and sizes of peroneal tubercle and retrotrochlear eminence (RTE), the prevalence of peroneus quartus (PQ), os peroneum, and boomerang-shaped peroneus brevis (PB) tendon, the shape of the retromalleolar fibular groove (RMFG), and the location of the PB muscle-tendon junction were evaluated. The relationships of these variations with peroneal tendinopathies were assessed. The correlations between pathological peroneal conditions on MRI and clinical findings were evaluated.

RESULTS

Peroneal tubercle (mean size, 3.2 mm) and RTE (mean size, 4.5 mm) were identified in 58 (84%) and 69 (100%) ankles respectively. PQ muscle, os peroneum, and boomerang-shaped PB tendon were found in 9 (13%), 7 (10%), and 24 (34.8%) ankles respectively. The RMFG was concave, flat, convex, and irregular in 14 (20.3%), 40 (58%), 13 (18.8%), and 2 (2.9%) ankles respectively. Sixteen (23.2%) patients had low-lying PB muscle belly. Only boomerang-shaped PB tendons showed a significant relationship with peroneal tendinopathies. MRI and clinical findings had a poor correlation in pathological peroneal conditions and both had low sensitivity in diagnosis.

CONCLUSION

Lateral ankle anatomical variations are common and cannot be attributed to pathological conditions of the peroneal tendon, except for boomerang-shaped PB tendons. Both clinical and MRI findings have low sensitivity in the diagnosis of peroneal tendinopathies, which are often incidental findings on MRI.