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. Methods. We retrospectively reviewed 537 consecutive cases of ankle fractures involving the medial malleolus treated in our institution. 3D fracture maps were produced by superimposing all the fracture lines onto a standard template. We sliced fracture fragments and the standard template based on selected sagittal and coronal planes to create 2D fracture maps, where angles α and β were measured. Angles α and β were defined as the acute angles formed by the fracture line and the horizontal line on the selected planes. Results. A total of 121 ankle fractures were included. We revealed several important fracture features, such as a high correlation between posterior collicular fractures and posteromedial fragments. Moreover, we generalized the fracture geometry into three recurrent patterns on the coronal view of 3D maps (transverse, vertical, and irregular) and five recurrent patterns on the lateral view (transverse, oblique, vertical, Y-shaped, and irregular). According to the fracture geometry on the coronal and lateral view of 3D maps, we subsequently categorized medial malleolar fractures into six types based on the recurrent patterns: anterior collicular fracture (27 type I, 22.3%), posterior collicular fracture (12 type II, 9.9%), concurrent fracture of anterior and posterior colliculus (16 type III, 13.2%), and supra-intercollicular groove fracture (66 type IV, 54.5%). Therewere three variants of type IV fractures: transverse (type IVa), vertical (type IVb), and comminuted fracture (type IVc). The angles α and β varied accordingly. Conclusion. Our findings yield insight into the characteristics and recurrent patterns of medial malleolar fractures. The proposed classification system is helpful in understanding injury mechanisms and guiding diagnosis, as well as surgical strategies. Cite this article: Bone Joint J 2021;103-B(5):931–938

There is an increasing acceptance that the clinical outcomes following posterior malleolar fractures are less than satisfactory. Current ankle classification systems do not account for differences in fracture patterns or injury mechanisms, and as such, the clinical outcomes of these fractures are difficult to interpret. The aim of this study was to analyse our posterior malleolar fractures to better understand the anatomy of the fracture. In a series of 42 consecutive posterior malleolar, who all underwent CT imaging, we have described anatomically different fracture patterns dictated by the direction of the force and dependent on talus loading. We found 3 separate categories. Type 1 – a rotational injury in an unloaded talus resulted in an extraarticular posterior avulsion of the posterior ligaments. This occurred in 10 patients and was most commonly associated with either a high fibular spiral fracture or a low fibular fracture with Wagstaffe fragment avulsion. The syndesmosis was usually disrupted in these patients. Type 2 – a rotational injury in a loaded talus resulting in a posterolateral articular fracture, of the posterior incisura. This occurred in 16 patients and was most commonly associated with a posterior syndesmosis injury, low fibular spiral fracture and an anterior collicular fracture of the medial malleolus. Type 3 – axially loaded talus in plantarflexion causing a posterior pilon. This occurred in 16 patients and was most commonly associated with a long oblique fracture of the fibular and a Y shape fracture of the medial malleolus. The syndesmosis was usually intact in these patients. In conclusion, the anatomy of the posterior malleolar should not be underestimated and requires careful consideration during treatment and categorisation in outcome studies to prevent misinterpretation

The AO Foundation advocates the use of partially threaded lag screws in the fixation of fractures of the medial malleolus. However, their threads often bypass the radiodense physeal scar of the distal tibia, possibly failing to obtain more secure purchase and better compression of the fracture. We therefore hypothesised that the partially threaded screws commonly used to fix a medial malleolar fracture often provide suboptimal compression as a result of bypassing the physeal scar, and proposed that better compression of the fracture may be achieved with shorter partially threaded screws or fully threaded screws whose threads engage the physeal scar. We analysed compression at the fracture site in human cadaver medial malleoli treated with either 30 mm or 45 mm long partially threaded screws or 45 mm fully threaded screws. The median compression at the fracture site achieved with 30 mm partially threaded screws (0.95 kg/cm. 2. (interquartile range (IQR) 0.8 to 1.2) and 45 mm fully threaded screws (1.0 kg/cm. 2 . (IQR 0.7 to 2.8)) was significantly higher than that achieved with 45 mm partially threaded screws (0.6 kg/cm. 2. (IQR 0.2 to 0.9)) (p = 0.04 and p < 0.001, respectively). The fully threaded screws and the 30mm partially threaded screws were seen to engage the physeal scar under an image intensifier in each case. The results support the use of 30 mm partially threaded or 45 mm fully threaded screws that engage the physeal scar rather than longer partially threaded screws that do not. A 45 mm fully threaded screw may in practice offer additional benefit over 30 mm partially threaded screws in increasing the thread count in the denser paraphyseal region. Cite this article: Bone Joint J 2013;95-B:1662–6

Introduction. We performed a longitudinal outcome study involving the operative management of ankle fractures at two university teaching hospitals. This was a retrospective review of the quality of reduction and a prospective study into the functional outcome. Methods. All patients undergoing open reduction internal fixation of the ankle between November 2006 and November 2007 at one centre, and January to December 2009 at the other were included. Adequacy of reduction was assessed on the initial post-operative radiographs using Pettrone's criterion. The post-operative functional outcome was recorded using the Lower Extremity Functional Scale (LEFS), completed by postal or telephone follow-up at 64 months post injury (60–74 months). Results. There were 261 patients in the cohort, with a mean age of 47 years (17–91). Weber B fractures were sustained in 193 patients compared to 68 Weber C fractures. The medial malleolus was fractured in 43 cases, and a large posterior malleolar fragment (>20%) was found in 13 cases. Malreduction of the Weber B cohort was identified in 61 ankles (31%): Malreduction of the Weber C cohort was identified in 25 cases (37%): At time of follow-up 26 patients were not traceable or had died. Of the surviving 235 patients, 139 responded to the LEFS questionnaire (60%). The mean LEFS was 58 (out of 80) in the Weber B cohort and 61 in the Weber C cohort. Significantly lower LEFS were found in patients who had a malreduction in 2 or more criteria. Conclusion. Our study shows that there is high incidence of malreduction in the operative treatment of ankle fractures which leads to a significantly poorer functional outcome. We strongly recommend that adequate care and supervision are used in theatre together with post-operative independent review of intra-operative fluoroscopy images

Aims

The Vantage Total Ankle System is a fourth-generation low-profile fixed-bearing implant that has been available since 2016. We aimed to describe our early experience with this implant.

Aim. A prospective cohort of patients undergoing total ankle arthroplasrty for arthritis following pilon fractures was included in the present study. This group of patients generally have poor soft tissue envelope and have had previous surgical interventions prior to the ankle arthroplasty, making the arthroplasty more difficult as well as prone to complications. Methods. The data collected included patient demographics, American Orthopaedic Foot and Ankle Score (AOFAS) and patient reported outcomes (FAOS, SF-36, patient satisfaction) The data was collected preoperatively and at 1 & 2 years postoperatively. The minimum follow-up period was 2 years post-operatively. Results. A total of 167 total ankle arthroplasties were performed by the senior author between Jan 2006 and June 2010. Of this cohort, the indication for 12 arthroplasties was arthritis following pilon fractures of the distal tibia. The average of the patients at the time of the surgery was 64.2yrs. The average number of previous surgeries prior to the ankle arthroplasty was 1.5. There were significant improvements in the AOFAS scores from an average of 18 to 75 at final review. The WOMAC scores improved from 31 to 71 for pain, stiffness improved from 31 to 60 and function improved from 33 to 63. The improvement of the SF36 and patient satisfaction score is similar to the ones for primary ankle osteoarthritis. The complications were: 1 case of superficial wound infection which settled with antibiotics, one fracture of medial malleolus and one case of undisplaced distal tibial fracture treated conservatively to union. Conclusion. The Indications for TAR can be safely broadened to include younger patients with arthritis following pilon fractures of the tibia. The Outcomes after TAR for patients with arthritis following pilon fractures are comparable to those for primary osteo arthritis of the ankle

Aims

We report the medium-term outcomes of a consecutive series of 118 Zenith total ankle arthroplasties (TAAs) from a single, non-designer centre.

The incidence of periprosthetic fractures of the ankle is increasing. However, little is known about the outcome of treatment and their management remains controversial. The aim of this study was to assess the impact of periprosthetic fractures on the functional and radiological outcome of patients with a total ankle arthroplasty (TAA).

A total of 505 TAAs (488 patients) who underwent TAA were retrospectively evaluated for periprosthetic ankle fracture: these were then classified according to a recent classification which is orientated towards treatment. The outcome was evaluated clinically using the American Orthopedic Foot and Ankle Society (AOFAS) score and a visual analogue scale for pain, and radiologically.

A total of 21 patients with a periprosthetic fracture of the ankle were identified. There were 13 women and eight men. The mean age of the patients was 63 years (48 to 74). Thus, the incidence of fracture was 4.17%.

There were 11 intra-operative and ten post-operative fractures, of which eight were stress fractures and two were traumatic. The prosthesis was stable in all patients. Five stress fractures were treated conservatively and the remaining three were treated operatively.

A total of 17 patients (81%) were examined clinically and radiologically at a mean follow-up of 53.5 months (12 to 112). The mean AOFAS score at follow-up was 79.5 (21 to 100). The mean AOFAS score in those with an intra-operative fracture was 87.6 (80 to 100) and for those with a stress fracture, which were mainly because of varus malpositioning, was 67.3 (21 to 93). Periprosthetic fractures of the ankle do not necessarily adversely affect the clinical outcome, provided that a treatment algorithm is implemented with the help of a new classification system.

Cite this article: Bone Joint J 2015;97-B:950–6.

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.

In a retrospective study we compared 32 HINTEGRA total ankle replacements (TARs) and 35 Mobility TARs performed between July 2005 and May 2010, with a minimum follow-up of two years. The mean follow-up for the HINTEGRA group was 53 months (24 to 76) and for the Mobility group was 34 months (24 to 45). All procedures were performed by a single surgeon.

There was no significant difference between the two groups with regard to the mean AOFAS score, visual analogue score for pain or range of movement of the ankle at the latest follow-up. Most radiological measurements did not differ significantly between the two groups. However, the most common grade of heterotopic ossification (HO) was grade 3 in the HINTEGRA group (10 of 13 TARs, 76.9%) and grade 2 in the Mobility group (four of seven TARs, 57.1%) (p = 0.025). Although HO was more frequent in the HINTEGRA group (40.6%) than in the Mobility group (20.0%), this was not statistically significant (p = 0.065).The difference in peri-operative complications between the two groups was not significant, but intra-operative medial malleolar fractures occurred in four (11.4%) in the Mobility group; four (12.5%) in the HINTEGRA group and one TAR (2.9%) in the Mobility group failed (p = 0.185).

Cite this article: Bone Joint J 2013;95-B:1075–82.

The Bologna–Oxford (BOX) total ankle replacement (TAR) was developed with the aim of achieving satisfactory pain-free movement of the ankle. To date, only one single multicentre study has reported its clinical results. The aim of this study was to conduct an independent review of its mid-term results.

We retrospectively reviewed a total of 60 prospectively followed patients in whom 62 BOX TARs had been implanted between 2004 and 2008. We used the American Orthopedic Foot and Ankle Society (AOFAS) score to assess the clinical results. Standardised radiographs taken at the time of final follow-up were analysed by two observers. The overall survival was 91.9% at a mean follow-up of 42.5 months (24 to 71). The mean AOFAS score had improved from 35.1 points (sd 16.6; 4 to 73) pre-operatively to 78.0 (sd 10.7; 57 to 100) at final follow-up (p < 0.01). Tibial radiolucencies < 2 mm in width were seen around 16 TARs. Talar radiolucencies < 2 mm were seen around four TARs. A total of 47 patients (78.3%) were very satisfied or satisfied with the outcome. Five patients required revision for functional limitation or continuing pain.

We describe the early results of a prospective study of 100 total ankle replacements (96 patients) at a single centre using the Mobility Total Ankle Replacement. At final review, six patients had died and five ankles (5%) had been revised, two by fusion and three by exchange of components. All remaining patients were reviewed at a minimum of three years. The mean follow-up was 43 months (4 to 63). The three-year survival was 97% (95% confidence interval (CI) 91 to 99). The four-year survival was 93.6% (95% CI 84.7 to 97.4). The portion of bony interface that was visible on plain radiograph was divided into 15 zones and a radiolucent line or osteolytic cavity was seen in one zone in 14 ankles. It was not seen in more than one zone. In five ankles it was > 10 mm in width.

This study suggests that the early outcome of ankle replacement is comparable to that of other total joint replacements.

In this retrospective study, using the prospectively collected database of the AO-Documentation Centre, we analysed the outcome of 57 malunited fractures of the ankle treated by reconstructive osteotomy. In all cases the position of the malunited fibula had been corrected, in several cases it was combined with other osteotomies and the fixation of any non-united fragments. Patients were seen on a regular basis, with a minimum follow-up of ten years. The aim of the study was to establish whether reconstruction improves ankle function and prevents the progression of arthritic changes.

Good or excellent results were obtained in 85% (41) of patients indicating that reconstructive surgery is effective in most and that the beneficial effects can last for up to 27 years after the procedure. Minor post-traumatic arthritis is not a contraindication but rather an indication for reconstructive surgery. We also found that prolonged time to reconstruction is associated negatively with outcome.

We describe the medium-term results of a prospective study of 200 total ankle replacements at a single-centre using the Scandinavian Total Ankle Replacement. A total of 24 ankles (12%) have been revised, 20 by fusion and four by further replacement and 27 patients (33 ankles) have died. All the surviving patients were seen at a minimum of five years after operation. The five-year survival was 93.3% (95% confidence interval (CI) 89.8 to 96.8) and the ten-year survival 80.3% (95% CI 71.0 to 89.6).

Anterior subluxation of the talus, often seen on the lateral radiograph in osteoarthritic ankles, was corrected and, in most instances, the anatomical alignment was restored by total ankle replacement. The orientation of the tibial component, as seen on the lateral radiograph, also affects the position of the talus and if not correct can hold the talus in an abnormal anterior position. Subtalar arthritis may continue to progress after total ankle replacement. Our results are similar to those published previously.

The precise localisation of osteoarthritic changes is crucial for selective surgical treatment. Single photon-emission CT-CT (SPECT-CT) combines both morphological and biological information. We hypothesised that SPECT-CT increased the intra- and interobserver reliability to localise increased uptake compared with traditional evaluation of CT and bone scanning together. We evaluated 20 consecutive patients with pain of uncertain origin in the foot and ankle by radiography and SPECT-CT, available as fused SPECT-CT, and by separate bone scanning and CT. Five observers assessed the presence or absence of arthritis. The images were blinded and randomly ordered. They were evaluated twice at an interval of six weeks. Kappa and multirater kappa values were calculated.

The mean intraobserver reliability for SPECT-CT was excellent (κ = 0.86; 95% CI 0.81 to 0.88) and significantly higher than that for CT and bone scanning together. SPECT-CT had significantly higher interobserver agreement, especially when evaluating the naviculocuneiform and tarsometatarsal joints.

SPECT-CT is useful in localising active arthritis especially in areas where the number and configuration of joints are complex.