Minimally invasive distal metaphyseal metatarsal osteotomy (DMMO) for symptomatic forefoot pathology - Short to medium term outcomes from a retrospective case series.

BACKGROUND: Minimally invasive distal metaphyseal metatarsal osteotomy (DMMO) may be used to treat metatarsalgia and forefoot pathology. Few large series report its results or examine the degree of metatarsal shortening with this technique. The clinical and radiographic results of a cohort of patients treated with DMMOs at our unit are reported. METHODS: This was a single-centre retrospective study looking at the outcome of consecutive patients undergoing DMMOs. Demographics, radiological and clinical outcomes, complications and patient reported outcome measures (PROMs) were analysed. RESULTS: DMMOs on 106 toes in 43 feet were included. Mean age was 60.2±10.2 years and median follow-up was 38 months. Concurrent procedures were performed in 26 cases (60%). DMMO was performed on multiple toes in 42 cases (97%). Mean shortening achieved was 3.6±2.2mm, 4.1±1.6mm, and 3.6±1.6mm for the second, third and fourth metatarsals respectively. Mean time to fusion was 11.4±7.8 weeks and union occurred in 105 toes (99%). The single non-union was asymptomatic at 12 months. Two patients required a subsequent additional DMMO for transfer metatarsalgia. Minor complications were seen in 11 patients (26%). At final follow-up PROMs data was available for 42 cases: mean MOxFQ was 28.8±27.6, mean EQ-5D was 0.789±0.225, mean EQ-VAS was 68.5±20.3, mean VAS-Pain score was 3.1±2.8, and patients were satisfied overall in 40 cases (95%). CONCLUSIONS: The authors demonstrate excellent radiological and clinical outcomes in the short to medium term with DMMOs and present data on metatarsal shortening achieved with this technique.

Is It Possible to Overcompress the Syndesmosis?

The case we present suggests that it might be possible to overcompress the syndesmosis, causing subluxation of the talus within the ankle mortise. A 26-year-old female patient had had a Weber Type C ankle fracture internally fixed with a lateral plate and syndesmosis screws. Despite the fibula appearing well reduced and computed tomography imaging showing a well-aligned fibula within the fibular notch, anteromedial subluxation of the talus was present in the ankle mortise. Examination with the patient under anesthesia revealed a stable syndesmosis fixation; however, talar malpositioning was not affected by the foot position. The syndesmosis fixation was revised sequentially. As the fixation was relaxed sequentially, the talus appeared to reduce within the ankle mortise, with restoration of the previously obliterated medial clear space. The syndesmosis was stabilized with a single 3.5-mm cortical screw in a reduced position. The patient had made a full recovery at the 12-month follow-up examination, having undergone elective syndesmosis screw removal at 12 weeks postoperatively. Several studies have suggested that it might not be possible to overcompress the syndesmosis and have even advocated the use of a lag screw technique for syndesmosis fixation. Based on the present case, we would advise a degree of caution with this approach, because it might be possible to overcompress the syndesmosis and cause significant subluxation of the tibiotalar articulation.

A rare Lisfranc-type injury involving dorsal dislocation of the intermediate cuneiform.

Lisfranc injuries occur at the tarsometatarsal joint resulting from direct or indirect force to the midfoot. They account for only 0.2% of all fractures, with diagnoses easily missed on presentation. The resultant instability is often associated with significant morbidity to the patient. This report describes a Lisfranc injury sustained by a healthy gentleman who suffered indirect trauma to the foot when he fell from a standing height. Plain film radiographs and CT revealed dorsal dislocation of the intermediate cuneiform associated with fractures at the base of the third and fourth metatarsals. He underwent open reduction and internal fixation the following day. His Foot and Ankle Disability Index (FADI) score improved from 16.3 1 week postoperatively to 58.7 6 months postoperatively. This report describes a rare injury pattern resulting from indirect, low-energy trauma. We provide a guide to appropriate radiological imaging and evaluation in the assessment of these complex injuries.