Peroneal tendon subluxation although rare, is a commonly misdiagnosed cause of lateral ankle pain and instability. The orientation and depth of the lateral retromalleolar groove is a major contributor to peroneal stability, but is little understood. We attempt to quantify the groove using three directional mapping techniques.

Eight age and sex matched embalmed cadaveric feet were dissected to expose the peroneal tendons and the retromalleolar groove. A hand held digitiser was used to map the version and inclination of the groove in a 3D virtual environment. The length and depth of the groove and its orientation were calculated using the cartilage boundary and the centroid of the curved surface.

Four male and four female specimens (mean age 80 Yrs) were studied. The groove was noted to be concave in 62%, flat in 25 % and concave in 12.5 %. Flatter groove were more commonly noted in (2/4) females. There was a significant difference in length and width of the groove between male and female feet. The mean length of the groove in male specimens was 6.2cm (5.4–6.7cm), and in female specimens 5.5cm (4.4–5.9cm). The mean width in males was 5.3mm (5.0–6.1mm) and in females 4.5mm (3.7–5.3mm). There was no significant difference noted in the depth of the groove between male and female feet. The mean depth in males was 2.3mm (0.8–3.1) and in female 2.2mm (0–2.4mm).

Knowledge of peroneal groove geometry in treatment of peroneal tendon instability is important. There appears to be a consistent difference in the anatomy of the groove between the sexes. Although men have longer and wider grooves than woman, the depth is the same in both sexes.

Introduction. The exact action of the Peroneus Longus muscle on the foot is not fully understood. It is involved in a number of pathological processes like tendonitis, tenosynovitis, chronic rupture and neurological conditions. It is described as having a consistent insertion to the base of the first metatarsal, but there have also been reports of significant variations and additional slips. Our aim was to further clarify the anatomy of the main insertion of the Peroneus Longus tendon and to describe the site and frequency of other variable insertion slips. Methods and Materials. The course of the distal peroneus longus tendon and its variable insertion was dissected in 12 embalmed, cadaveric specimens. The surface area of the main insertion footprint and angle of insertion was measured using an Immersion Digital Microscribe and 3D mapping software. The site and frequency of the other insertion slips is also presented. Results. There was a consistent, main insertion to the infero-lateral aspect of the first metatarsal in all specimens. The only additional slip was to the medial cuneiform. This did not increase the total footprint. Discussion. The main footprint of the Peroneus Longus tendon is on the first metatarsal. There was an additional slip to the medial cuneiform in 33% of our specimens. Although we are unsure about the significance of this additional slip, we hope it will lead to a better understanding of the mechanism of action of this muscle and its role both in the normal and pathological foot

Background. Talar neck fractures occur infrequently and are associated with high complication rates. Anatomical restoration of articular congruity is important. Adequate exposure and stable internal fixation of these fractures are challenging. Aims. We investigate the use of an anterior extensile approach for exposure of these fractures and their fixation by screws introduced through the talo-navicular articulation. We also compare the quality and quantity of exposure of the talar neck obtained by this approach with the commonly described combined medial/lateral approaches. Materials and Methods. An anterior approach to the talus between the tibialis anterior and the extensor hallucis longus tendons protecting both the superficial and deep peroneal nerves was performed on 5 fresh frozen cadaveric ankles . The surface area of talar neck accessible was measured using an Immersion Digital Microscibe and analysed with Rhinoceros 3D graphics package. Standard antero-medial and antero –lateral approaches were also carried out on the same ankles, and similar measurements taken. Seven patients with talar neck fractures (4 Hawkins Type II and 3 Hawkins Type III) who underwent operative fixation using this approach with parallel cannulated screws through the talo-navicular joint were followed and the clinical radiological outcomes were recorded. Results. 3D mapping demonstrated that talar surface area visible by the anterior approach (mean 1200sqmm) is consistently superior to that visible by either the medial or lateral approaches in isolation or in combination (mean medial 350sqmm, mean lateral 600sqmm). Medial malleolar osteotomy does not offer any additional visualisation of the talar neck. 3D reconstruction of the area visualised by the three approaches confirms that the anterior approach provides superior access to the entirety of the talar neck. 5 male and 2 female patients (mean age -) were reviewed at a mean follow up period of 6 months. All had anatomical articular restoration, and no wound problems. None developed non or AVN. There were no symptoms referable to the talo-navicular joints which showed no evidence of any secondary changes on the radiographs. Discussion. The anterior extensile approach offers superior visualisation of the talar neck in comparison to other approaches for anatomical articular restoration. Surgical morbidity with this approach is low, and introduction of screws through the talo-navicular joint allows stable fixation of talar neck fractures along the axis of the bone. We argue that this approach is safe, adequate and has the potential to cause least vascular disruption

Aims

The morphology of medial malleolar fracture is highly variable and difficult to characterize without 3D reconstruction. There is also no universally accepeted classification system. Thus, we aimed to characterize fracture patterns of the medial malleolus and propose a classification scheme based on 3D CT reconstruction.