MIS (minimally invasive surgery) aims to improve cosmesis and facilitate early recovery by using a small skin incision with minimal soft tissue disruption. When using MIS in the forefoot, there is concern about neurovascular and tendon damage and cutaneous burns. The aim of this anatomical study was to identify the structures at risk with the proposed MIS techniques and to determine the frequency of iatrogenic injury. 10 paired normal cadaver feet were used. All procedures were performed using a mini C-arm in a cadaveric lab by 2 surgeons: 1 consultant who has attended a cadaveric MIS course but does not perform MIS in his regular practice (8 feet), and 1 registrar who was supervised by the same consultant (2 feet). In each foot, the surgeon performed a lateral release, a MICA (minimally invasive chevron and Akin) procedure for the correction of The dorsal medial cutaneous and the plantar interdigital nerves were intact in all specimens. There was no obvious damage to the arterial plexus supplying the first metatarsal head. No flexor or extensor tendon injuries were identified. There is a significant learning curve to performing the osteotomy cuts in the desired plane. In the DMO, the dissection also revealed some intact soft tissue at the osteotomy site indicating that the metatarsal heads were not truly floating.Materials and Methods
Results
Determination of ankle stability is straightforward when the injury involves both the medial and lateral For the study 10 fresh-frozen cadaveric lower limbs were used. Mortise radiographs were taken at neutral, 15 and 30 degrees of plantarflexion and neutral external rotation. These measurements were repeated after dividing the deltoid ligament. To ensure consistent ankle position, the ankle was placed in a specially constructed rig, which recreated the above positions. The medial clear space and talar tilt were measured. Differences in the means between the groups were determined with the paired âtâ test and ANOVA within the groups. Statistical significance was set a p-value of 0.05. Increasing the plantarflexion from neutral to 30 degrees in both groups resulted in increase in the medial clear space and talar tilt. The mean increase in medial clear space became statistically significant at 30 degrees when compared to neutral. Between the groups there was a significant difference in medial clear space at 30 degrees plantarflexion. Dividing the deltoid ligament also had a significant effect on talar tilt. Plantarflexion has an influence on the medial clear space in ankle mortise views therefore pre and post ankle fixation radiographs must be interpreted with caution.
