2015 ISAKOS Biennial Congress ePoster #130
Hindfoot Endoscopic Findings of the Posterior Intermalleolar Ligament in the Posterior Ankle Impingement Syndrome in Ballet Dancers
Eiichi Hiraishi, MD, Tokyo JAPAN
Kenichiro Takeshima, MD, Chiba JAPAN
Kanako Kudo, MD, Tokyo JAPAN
Hiroko Ikezawa, MD, Tokyo JAPAN
Norio Usami, MD, Tokyo JAPAN
Eiju General Hospital, Tokyo, JAPAN
FDA Status Cleared
Summary: PIML was not a rare structure and observed in various shape. Some of them were impinged between posterior lip of the tibia and the tendon sheath of the FHL, very similar to the Bassett’s ligament in the anterolateral aspect of the ankle.
Abstract:
Introduction
Posterior ankle pain is a common but a serious problem in ballet dancers. There have been reported various kinds of pathological conditions and bony impingement (BI) and flexor hallucis longus (FHL) pathology are well known as the major causes of the posterior ankle impingement syndrome (PAIS). Even after resection of impinged bone, tenolysis and/or a repair of the FHL tendon, there are some patients suffering from a discomfort or a pain in the hindfoot. Recently soft tissue impingement due to a posterior intermalleolar ligament (PIML) has been focused in some papers.
The purpose of this study was to clarify the impingement of PIML through hindfoot endoscopy.
[Patients and Method]
Between September 2007 and July 2014, 88 feet of 80 ballet dancers, including six feet of five male dancers, underwent hindfoot endoscopic surgery due to PAIS. Average age was 21.9 years (ranged 12-54) at the time of surgery. The shape, location, and behavior of PIML were retrospectively analyzed with operative findings. We define the PIML a ligamentous structure located below the posterior lip of the tibia medial to the FHL tendon. Surgical technique presented by van Dijk was applied to all feet.
Results
PIML were found in 59 feet (67.0%), ranging from about 1 to 5 mm in width in comparison with a probe’s tip. The majority of them were located behind the posterior malleolus like a curtain, with or without a synovium-like soft tissue. In four feet of four dancers, a meniscus-like PIML, which were slipped in the ankle joint, were observed. In another five feet of five dancers, PIML moved with a passive motion of the greater toe. And there were a certain number of dancers who had thickened synovia between PIML and FHL tendon sheath which was impinged in ankle plantar flexion.
Great majority of feet were affected two or more pathologic conditions such as combined BI with FHL pathology, and there wasn’t a case only with PIML impingement.
Discussion
Rosenberg et al (1995) reported that PIML were found in 56% of the cadaveric ankles and that its occasional extension into the ankle joint may account for development of PAIS. Oh et al (2006) reported the occurrence in 81.8% of the cadaveric ankles. Golano (20110) clearly showed the PIML impingement in a cadaveric ankle.
As for the clinical cases, Hamilton et al (1994) reported pseudomeniscus syndrome, Fiorella et al (1999), and Giannini et al (2013) presented PIML as a marsupial meniscus through the anterior ankle arthroscopy.
In this study, we found PIML in 67.0% of the feet. The occurrence was rather lower than the latest cadaveric studies, because hindfoot endoscopy may require initial taking off the soft tissue of the hindfoot. In case PIML impinged or looked degenerated, resection was indicated. But, from an outlook, it is still difficult to distinguish whether normal or not.
Conclusion
PIML was not a rare structure and observed in various shape. Some of them were impinged between posterior lip of the tibia and the tendon sheath of the FHL. Their behavior is very similar to the Bassett’s ligament in the anterolateral aspect of the ankle. It is necessary to treat PIML in case the impingement presents, in addition to BI, FHL pathologies, and so on.