Introduction. Fibula shortening with an intact anterior tibiofibular ligament (ATFL) and medial ligament instability causes lateral translation of the talus. Our hypothesis was that the interaction of the AITFL tubercle of the fibular with the tibial incisura would propagate lateral translation due to the size differential. Aim. To assess what degree of shortening of the fibular would cause the lateral translation of the talus. Methodology. Twelve cadaveric ankle specimens were dissected removing all soft tissue except for ligaments. They were fixed on a specially-designed platform within an augmented ankle cage allowing tibial fixation and free movement of the talus. The fibula was progressively shortened in 5mm increments until complete ankle dislocation. The medial clear space was measured with each increment of shortening. Results. The larger AITFL tubercle interaction with the smaller tibial incisura caused a significant increase in lateral translation of the talus. This occurred in most ankles between 5–10mm of fibular shortening. The medial clear space widened following 5mm of shortening in 5 specimens (mean=2.0725, SD=±2.5338). All 12 specimens experienced widening by 10mm fibula shortening (Mean=7.2133mm, SD=±2.2061). All specimens reached complete dislocation by 35mm fibula shortening. Results of ANOVA analysis found the data statistically significant (p<0.0001). Conclusion. This study shows that shortening of the fibula causes a significant lateral translation of the talus provided the ATFL remains intact. Furthermore, the interaction of the fibula notch with the ATFL tubercle of the tibia appears to cause a disproportionate widening of the medial clear space due to its differential in size. Knowledge of the extent of fibula shortening can guide further intervention when presented with a patient experiencing medial clear space widening following treatment of an ankle fracture

Determination of ankle stability is straightforward when the injury involves both the medial and lateral malleolus. However it can be challenging when the medial injury involves the deltoid ligament. Radiographic diagnosis of ankle instability highly depends on the measurement of medial clear space. As the shape of talus has been postulated akin to a trapezoid, the medial clear space may be influenced by the portion of talus occupying the mortise. Hence the medial clear space may be influenced by the position of the ankle. We sought to evaluate the impact of ankle plantarflexion and division of the deltoid ligament on the medial clear space. 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 ‘t’ 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

Supination-external rotation (SER) fractures of the ankle may present with a medial ligamentous injury that is not apparent on the initial radiographs. A cadaver gravity-stress view has been described, but the manual-stress view is considered to be the examination of choice for the diagnosis of medial injuries. We prospectively compared the efficacy of these two examinations. We undertook both examinations in 29 patients with SER fractures. Of these, 16 (55%) were stress-positive, i.e. and had widening of the medial clear space of > 4 mm with a mean medial clear space of 6.09 mm (4.4 to 8.1) on gravity-stress and 5.81 mm (4.0 to 8.2) on manual-stress examination, and 13 patients (45%) were stress-negative with a mean medial clear space of 3.91 mm (3.3 to 5.1) and 3.61 mm (2.6 to 4.5) on examination of gravity- and manual-stress respectively. The mean absolute visual analgoue scale score for discomfort in the examination of gravity stress was 3.45 (1 to 6) and in the manual-stress procedure 6.14 (3 to 10). We have shown that examination of gravity-stress is as reliable and perceived as more comfortable than that of manual stress. We recommend using it as the initial diagnostic screening examination for the detection of occult medial ligamentous injuries in SER fractures of the ankle

Aims. To identify a core outcome set of postoperative radiographic measurements to assess technical skill in ankle fracture open reduction internal fixation (ORIF), and to validate these against Van der Vleuten’s criteria for effective assessment. Methods. An e-Delphi exercise was undertaken at a major trauma centre (n = 39) to identify relevant parameters. Feasibility was tested by two authors. Reliability and validity was tested using postoperative radiographs of ankle fracture operations performed by trainees enrolled in an educational trial (IRCTN 20431944). To determine construct validity, trainees were divided into novice (performed < ten cases at baseline) and intermediate groups (performed ≥ ten cases at baseline). To assess concurrent validity, the procedure-based assessment (PBA) was considered the gold standard. The inter-rater and intrarater reliability was tested using a randomly selected subset of 25 cases. Results. Overall, 235 ankle ORIFs were performed by 24 postgraduate year three to five trainees during ten months at nine NHS hospitals in England, UK. Overall, 42 PBAs were completed. The e-Delphi panel identified five ‘final product analysis’ parameters and defined acceptability thresholds: medial clear space (MCS); medial malleolar displacement (MMD); lateral malleolar displacement (LMD); tibiofibular clear space (TFCS) (all in mm); and talocrural angle (TCA) in degrees. Face validity, content validity, and feasibility were excellent. PBA global rating scale scores in this population showed excellent construct validity as continuous (p < 0.001) and categorical (p = 0.001) variables. Concurrent validity of all metrics was poor against PBA score. Intrarater reliability was substantial for all parameters (intraclass correlation coefficient (ICC) > 0.8), and inter-rater reliability was substantial for LMD, MMD, TCA, and moderate (ICC 0.61 to 0.80) for MCS and TFCS. Assessment was time efficient compared to PBA. Conclusion. Assessment of technical skill in ankle fracture surgery using the first postoperative radiograph satisfies the tested Van der Vleuten’s utility criteria for effective assessment. 'Final product analysis' assessment may be useful to assess skill transfer in the simulation-based research setting. Cite this article: Bone Jt Open 2022;3(6):502–509

Introduction. Deltoid ligament reconstruction (DLR) is an important factor in the consideration of pes planus deformity. There is little evidence in the literature determining whether DLR could mitigate the risk of patients acquiring flat foot postoperatively following deltoid ligament injury. Aim. Our objective was to establish if there was a difference in pes planus deformity in patients who underwent DLR during their ankle fracture fixation compared to those who did not. Methods. A retrospective analysis of post-operative weight bearing radiographs was performed of patients who underwent ankle fracture fixation. Inclusion criteria were confirmed deltoid instability presurgery without medial malleolar fracture and post operative weightbearing radiographs at least 6 weeks post-fixation. Patients were categorised into no deltoid ligament reconstruction (nDLR) and having DLR. Radiographic pes planus parameters involved Meary's Angle assessment. Other fracture morphology was classified. Results. A total 723 ankle fractures were screened. 122 patients were included for further analysis. There were 94 patients in the nDLR group and 28 patients in DLR group. The mean Meary's Angle was 15.81 (95% CI 14.06, 17.56) degrees in the nDLR group and −.2 (95% CI −3.86, 3.82) in the DLR group. This was statistically significant (p<.001). There was no significant difference in medial clear space measurements (2.90mm v 3.19mm, p = 0.145). There were significantly more pes planus patients in the nDLR than the DLR group (p<.001, 90.5% vs 25%). Conclusion. In this study there was significantly greater pes planus parameters in patients not undergoing DLR. Patients undergoing DLR had on average normal parameters, whilst those not undergoing DLR had on average severe pes planus. The benefits of DLR are not only maintaining ankle stability but maintaining medial arch integrity, and this should be taken into account in a future study on DLR

Introduction. The conservative management of stable Weber B fibula fractures remains variable. We thought that the current trend in our institution poses an unnecessary burden on fracture clinics. Methods. We reviewed patients referred with Weber B ankle fractures over an 18 month period. Our inclusion criteria were non-diabetic adults, with isolated stable Weber B fractures. Fractures were deemed stable if they had no evidence of talar shift on initial radiographs (< 5mm medial clear space and < 1mm variation between superior and medial clear spaces). Exclusion criteria were unstable fractures on radiographs, or no local follow-up. Management was reviewed from case notes and radiographs. Primary outcome was the stability of the fracture by the end of treatment. Secondary measures were duration of treatment, number of follow up appointments and radiographs, and complications. Results. 182 cases were reviewed. 82 were excluded leaving 100 patients for follow-up. Mean age was 53 (18–99). Mean number of outpatient appointments was 2.63 (1–6), follow up radiographs was 2.34 (0–6). 74 were treated in a walking boot and 15 in a walking cast for a mean of 6 weeks (4–9) and allowed to full weight-bear. 10 were kept non weight-bearing in a cast for 6 weeks and 1 was partially weight-bearing. Mean follow-up time was 7.3 weeks (1–30). No fractures displaced and one patient developed an ulcer from a cast. Conclusion. Our study suggests that in isolated Weber B fractures, with no radiographic instability on initial presentation, further displacement is unlikely. We propose that these injuries can be treated safely in a removable boot with full weight-bearing for 6 weeks then clinical and radiologic assessment if required. Casting or restricted weight-bearing does not confer any additional advantage. We question the necessity and rationale behind weekly clinical and radiological follow-up for such cases

During surgical reduction of ankle injuries with syndesmotic instability surgeons often use the anteroposterior (AP) and mortise radiographs to assess reduction. Current literature predicts 50% are malreduced mainly in the sagittal plane. Our aim was to develop a radiographic measure based on the lateral view to assess both the normal and abnormal fibula/tibia relationship after simulated syndesmotic malreduction and to evaluate the effect on commonly used AP and mortise measurements. Nine fresh-frozen cadaveric specimens were dissected to the level of the syndesmosis. AP, mortise and talar dome lateral radiographs were obtained before and following syndesmosis division and posterior fibula displacement. On the lateral radiograph a line was drawn (Orthoview) from the anterior border of the fibula bisecting a line drawn from the anterior to posterior lips of the distal tibia. The ratio of the anterior-posterior segments was calculated. Also a line was drawn from the posterior border of the fibula and the distance was measured to the posterior lip of the tibia. At 0, 2, 4 and 6mm of displacement the ratio measured 1.3±0.2, 1.1±0.2, 0.9±0.2 and 0.7±0.2 respectively with all pairwise comparisons being significantly different. Inter- and intra-observer variability varied from substantial to perfect. The only significant medial clear space (MCS) difference was on the mortise view between 0mm (2.0±0.3mm) and 6mm (2.4±0.4mm) displacement. Our new measure of syndesmotic reduction is reproducible and can detect from 2mm of saggital fibular displacement. At maximum fibular displacement the increase in MCS was less than 1mm. This demonstrates standard mortise radiographs are poor at detecting syndesmotic reduction. An interesting observation was in all specimens prior to any displacement, the posterior fibular line always bisected the posterior lip of the tibia or lay just anterior to it, never posterior. This could serve as a useful adjunct for surgeons when assessing syndesmotic reduction intra-operatively

Aims

There has been an evolution recently in the management of unstable fractures of the ankle with a trend towards direct fixation of a posterior malleolar fragment. Within these fractures, Haraguchi type 2 fractures extend medially and often cannot be fixed using a standard posterolateral approach. Our aim was to describe the posteromedial approach to address these fractures and to assess its efficacy and safety.