Introduction. Charcot neuroarthropathy is a debilitating condition that frequently leads to skeletal instability, and has an increased risk of ulceration leading to infection and amputation. However, surgical reconstruction may offer limb salvage and restauration of an ulcer-free, plantigrade stable foot for functional weight-bearing. We report on our case series according to a prospective protocol and analyse factors leading to a favourable outcome. Methods. We report a prospective follow-up of 62 patients undergoing Charcot reconstruction, May 2014- Jan 2022, by two surgeons. Peripheral vascular disease was routinely assessed using Duplex scan and major arterial disease was treated before reconstruction. Utilising 3D modelling, pre-operative planning and standardised osteotomies, we performed anatomical correction with radiological evidence. Definitive fixation was undertaken with internal fixation to stabilise the hindfoot. Multivariant analysis was performed to assess risk factors for failure (P>0.05 statistical significance). Results. 59 feet were included, 3 patients did not progress to definitive surgery and 3 patients had bilateral surgery. 62.7% patients were male with an average age of 56, 88.13% had Type 2 diabetes, 56% were hypertensive, 14% were on dialysis. Twenty (54.1%) single stage reconstructions had pre-operative ulceration, 3 pts had ischaemic heart disease and 36 pts had evidence of peripheral arterial disease. 81% of patients achieved normalisation of the 3 out of 4 anatomical angles (P<0.05). Two patients (3.1%) required metalwork removal for infection and limb salvage, 11 (18.6%) had delayed wound healing. Survivorship was 97% at 3yrs, and 94% at 6yrs, however if pre-existing vascular disease was present, it was 94% at 3yrs 85.3% at 6yrs. All patients were mobile at a 3 years mean follow up. Conclusion. Careful patient selection, multidisciplinary team and anatomic reconstruction led to predictable outcomes and functional limb salvage. Pre-operative vascular compromise led to a slight reduction in survivorship, but no major amputation

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.

Aims

The ideal management of acute syndesmotic injuries in elite athletes is controversial. Among several treatment methods used to stabilize the syndesmosis and facilitate healing of the ligaments, the use of suture tape (InternalBrace) has previously been described. The purpose of this study was to analyze the functional outcome, including American Orthopaedic Foot & Ankle Society (AOFAS) scores, knee-to-wall measurements, and the time to return to play in days, of unstable syndesmotic injuries treated with the use of the InternalBrace in elite athletes.

Aims. The aim of this prospective study was to evaluate the intermediate-term outcomes after revision anatomical ankle ligament reconstruction augmented with suture tape for a failed modified Broström procedure. Patients and Methods. A total of 30 patients with persistent instability of the ankle after a Broström procedure underwent revision augmented with suture tape. Of these, 24 patients who were followed up for more than two years were included in the study. There were 13 men and 11 women. Their mean age was 31.8 years (23 to 44). The mean follow-up was 38.5 months (24 to 56) The clinical outcome was assessed using the Foot and Ankle Outcome Score (FAOS) and the Foot and Ankle Ability Measure (FAAM) score. The stability of the ankle was assessed using stress radiographs. Results. The mean FAOS and FAAM scores improved significantly to 87.5 (73 to 94) and 85.1 (70 to 95) points at final follow-up, respectively (p < 0.001). The mean angle of talar tilt and anterior talar translation improved significantly to 2.8° (0° to 6°) and 4.1 mm (2 to 7) at final follow-up, respectively (p < 0.001). Side to side comparison in stress radiographs at final follow-up showed no significant difference. The revision failed in one patient who underwent a further revision using allograft tendon. Conclusion. The revision modified Broström procedure augmented with suture tape is an effective form of treatment for recurrent instability of the ankle following a failed Broström procedure. This technique provides reliable stability and satisfactory clinical outcomes at intermediate-term follow-up. Cite this article: Bone Joint J 2017;99-B:1183–9

Introduction. Minimally invasive Achilles tendon repair has recently gained popularity amongst foot and ankle surgeons. This study aims to quantify the risk of sural nerve injury when using the Achillon device (Integra), as well as delineate its anatomical relationship to the Achilles tendon. Methods. In 15 cadaveric specimens, the Achilles tendon was transected through a 2cm transverse incision made 4cm proximal to the palpable Achilles tendon insertion point. The Achillon device was inserted beneath the paratenon both proximally and distally and six needle passers mounted with sutures were introduced percutaneously into the tendon (x3 proximal and x3 distal). We dissected around the Achillon jig to determine whether the needle and suture had punctured the sural nerve. We also documented the position of the sural nerve in relation to the Achilles tendon. Results. The mean horizontal distance from the Achilles tendon insertion to the sural nerve was 22.5mm (15.9mm–30.2mm). The mean vertical distance from the Achilles tendon insertion to the point where the sural nerve crosses the lateral border of the tendon was 96.1mm (77.4mm–134.9mm). In 4 out of 15 cadaveric specimens (27%) the sural nerve was punctured. In total, the sural nerve was punctured 6 times (twice in 2 specimens) in 90 needle passes (6.7%). Five out of the 6 punctures occurred when the Achillon device was inserted into the distal tendon portion with the most proximal hole being responsible for 3 of the punctures. Conclusions. The sural nerve displays a highly variable anatomical course and our findings highlight a significant risk of puncture during percutaneous Achilles tendon repair using the Achillon device. More studies are needed to clarify whether this risk equates to a significant clinical problem and whether a change in technique or instrumentation can decrease this risk

Isolated talonavicular arthrodesis is a common procedure particularly for posttraumatic arthritis and rheumatoid arthritis. Two surgical approaches are commonly used: the medial approach and the dorsal approach. It is recognized that access to the lateral aspect of the talonavicular joint can be limited when using the medial approach and it is our experience that using the dorsal approach addresses this issue. We performed an anatomical study using cadaver specimens, to compare the amount of articular surface that can be accessed, and therefore prepared for arthodesis, by each surgical approach. Medial and dorsal approaches to the talonavicular joint were performed on each of 10 cadaveric specimens. Distraction of the joint was performed as standard for preparation of articular surfaces during talonavicular arthrodesis. The accessible area of articular surface was marked for each of the two approaches. Disarticulation was performed and the marked surface area was quantified using a digital Microscribe allowing a three dimensional virtual model of the articular surfaces to be assessed. This study will provide quantifiable measurements of the articular surface accessible by the medial and dorsal approaches to the talonavicular joint. These data may provide support for the use of the dorsal approach for talonavicular arthrodesis

Introduction:. Peroneal muscle weakness is a common pathology in foot and ankle surgery. Polio, charcot marie tooth disease and spina bifida are associated with varying degrees of peroneal muscle paralysis. Tibialis Posterior, an antagonist of the peroneal muscles, becomes pathologically dominant, causing foot adduction and contributes to cavus foot posture. Refunctioning the peroneus muscles would enhance stability in toe off and resist the deforming force of tibialis posterior. This study determines the feasibility of a novel tendon transfer between peroneus longus and gastrocnemius, thus enabling gastrocnemius to power a paralysed peroneus tendon. Method:. 12 human disarticulated lower limbs were dissected to determine the safety and practicality of a tendon transfer between peroneus longus and gastrocnemius at the junction of the middle and distal thirds of the fibula. The following measurements were made and anatomical relationships quantified at the proposed site of the tendon transfer: The distance of the sural nerve to the palpable posterior border of the fibula; the angular relationship of the peroneus longus tendon to gastrocnemius and the achilles tendon; the surgical field for the proposed tendon transfer was explored to determine the presence of hazards which would prevent the tendon transfer. Results:. The mean angle between the tendons of peroneus longus and gastrocnemius/achilles tendon was 3°. The sural nerve lies on average 30 mm posterior to the palpable posterior border of the fibula. There were no significant intervening structures to prevent the proposed tendon transfer. Conclusion:. The line of action of peroneus longus and gastrocnemius are as near parallel as to be functionally collinear. The action of gastrocnemius may be harnessed to effectively power a paralysed peroneus longus tendon, without significant loss of force owing to revectoring of forces. The surgical approach to effect such a tendon transfer is both safe and practical

We dissected 12 fresh-frozen leg specimens to identify the insertional footprint of each fascicle of the Achilles tendon on the calcaneum in relation to their corresponding muscles. A further ten embalmed specimens were examined to confirm an observation on the retrocalcaneal bursa. The superficial part of the insertion of the Achilles tendon is represented by fascicles from the medial head of the gastrocnemius muscle, which is inserted over the entire width of the inferior facet of the calcaneal tuberosity. In three specimens this insertion was in continuity with the plantar fascia in the form of periosteum. The deep part of the insertion of the Achilles tendon is made of fascicles from the soleus tendon, which insert on the medial aspect of the middle facet of the calcaneal tuberosity, while the fascicles of the lateral head of the gastrocnemius tendon insert on the lateral aspect of the middle facet of the calcaneal tuberosity. A bicameral retrocalcaneal bursa was present in 15 of the 22 examined specimens.

This new observation and description of the insertional footprint of the Achilles tendon and the retrocalcaneal bursa may allow a better understanding of the function of each muscular part of the gastrosoleus complex. This may have clinical relevance in the treatment of Achilles tendinopathies.

Cite this article: Bone Joint J 2014; 96-B:1344–8

We performed a retrospective study to assess the long-term outcome of non-augmented anatomical direct repair of the lateral ankle ligaments, as originally described by Duquennoy et al, for the treatment of chronic lateral instability of the ankle. This procedure aims to restore stability by the re-insertion and tightening of the original talofibular and calcaneofibular ligaments without division of the ligament. We examined the outcome in terms of the post-operative quality of life, the function of the joint and the development of osteoarthritis. Between 1985 and 2002, 23 patients (11 males, 12 females) with a mean age of 32 years (15 to 58) who had undergone this procedure completed the Short-Form 36 assessment of quality of life and the Olerud and Molander Ankle score for the subjective evaluation of symptoms. Clinical re-evaluation, including examination of the ankle and the completion of the American Orthopaedic Foot and Ankle Society questionnaire was performed on 21 patients after a mean follow-up of 13 years (3 to 22.2). At the final follow-up radiographs of both ankles were taken to assess the development of osteoarthritis. The mean total Short-Form 36 and Olerud and Molander Ankle scores in 23 patients at final follow-up were 79.6 points (37 to 100) and 81.6 points (40 to 100), respectively. The mean total post-operative American Orthopaedic Foot and Ankle Society score in 21 patients was 89.7 points (72 to 100). We found a significant post-operative reduction in talar tilt and anterior drawer sign (chi-squared test, p < 0.001). The functional outcome of the procedure was excellent in ten patients (48%), good in seven (33%) and fair in four (19%). The results in terms of ankle function and stability did not deteriorate with time and there was little restriction in movement. This procedure is simple and effective with a very low rate of complications

We describe a medial midline portal between the tendons of extensor hallucis longus and tibialis anterior for arthroscopy of the ankle. We dissected 20 cadaver specimens to compare the risk of neurovascular injury using this approach with that of using standard arthroscopic portals. Compared with the anterocentral portal, the medial midline was a mean of 11.2 mm further from the nearest branch of the superficial peroneal nerve and 10.3 mm further from the dorsalis pedis artery.

This portal allows good access to the joint surface and intra-articular structures and has a lower risk of injury to the dorsalis pedis artery, deep peroneal nerve or the medial branch of the superficial peroneal nerve.

Aims. The Manchester-Oxford Foot Questionnaire (MOxFQ) is an anatomically specific patient-reported outcome measure (PROM) currently used to assess a wide variety of foot and ankle pathology. It consists of 16 items across three subscales measuring distinct but related traits: walking/standing ability, pain, and social interaction. It is the most used foot and ankle PROM in the UK. Initial MOxFQ validation involved analysis of 100 individuals undergoing hallux valgus surgery. This project aimed to establish whether an individual’s response to the MOxFQ varies with anatomical region of disease (measurement invariance), and to explore structural validity of the factor structure (subscale items) of the MOxFQ. Methods. This was a single-centre, prospective cohort study involving 6,637 patients (mean age 52 years (SD 17.79)) presenting with a wide range of foot and ankle pathologies between January 2013 and December 2021. To assess whether the MOxFQ responses vary by anatomical region of foot and ankle disease, we performed multigroup confirmatory factor analysis. To assess the structural validity of the subscale items, exploratory and confirmatory factor analyses were performed. Results. Measurement invariance by pathology was confirmed, suggesting the same model can be used across all foot and ankle anatomical regions. Exploratory factor analysis demonstrated a two- to three-factor model, and suggested that item 13 (inability to carry out work/everyday activities) and item 14 (inability to undertake social/recreational activities) loaded more positively onto the “walking/standing” subscale than their original “social interaction” subscale. Conclusion. This large cohort study supports the current widespread use of the MOxFQ across a broad range of foot and ankle pathologies. Our analyses found indications that could support alterations to the original factor structure (items 13 and 14 might be moved from the “social interaction” to the “walking/standing” subscale). However, this requires further work to confirm. Cite this article: Bone Joint J 2024;106-B(3):256–261

Background. The Manchester-Oxford Foot Questionnaire (MOxFQ) is a condition specific patient reported outcome measure (PROM) for foot and ankle surgery. It consists of 16 items across three subscales measuring distinct, but related traits: walking/standing ability, pain, and social interaction. Although it is the most used foot and ankle PROM in the UK, initial MOxFQ validation involved analysis of only 100 individuals undergoing hallux valgus surgery. This project aimed to establish whether an individual's response to the MOxFQ varies with anatomical region of disease (measurement invariance), and to explore structural validity of the factor structure (subscale items) of the MOxFQ. Methods. This was a single-centre, prospective cohort study involving 6640 patients (mean age 52, range 10–90 years) presenting with a wide range of foot and ankle pathologies between 2013 and 2021. Firstly, to assess whether the MOxFQ responses vary by anatomical region of foot and ankle disease, we performed multi-group confirmatory factor analysis. Secondly, to assess the structural validity of the subscale items, exploratory and confirmatory factor analyses were performed. Results. Measurement invariance by pathology was confirmed suggesting the same model can be used across all foot and ankle anatomical regions. Exploratory factor analysis demonstrated a 2–3 factor model, and suggested that item 13 (inability to carry out my work/everyday activities) and item 14 (inability to undertake social/recreational activities) loaded more positively onto the walking/standing subscale than their original social interaction subscale. Conclusions. This large-cohort study supports the current widespread use of the MOxFQ across a broad range of foot and ankle pathologies. Items 13 and 14 might be better moved from the “social interaction” to the “walking/standing” subscale and this may have future implications for deriving/analysing subscale scores

Talar body fractures are high energy intraarticular injuries that are best management by anatomical reduction and secure fixation to improve outcomes. The talus is relatively inaccessible surgically and requires extensive soft tissue dissection and/or osteotomies to gain adequate open visualisation. There are a small number of case reports on arthroscopic assisted fixation in the literature. This case series reports on the technique and early outcomes of six patients all of whom presented with significant intraarticular displacement and who were managed entirely arthroscopically. The fractures were of the main body of the talus involving the ankle and subtalar joints and all had preoperative CT scans. All six patients underwent posterior ankle and subtalar arthroscopy with cannulated screws used to stabilise the fractures after reduction. Visualisation of the fracture reduction was excellent. After 10 days in a backslab, the patients were protected in a boot and encouraged to actively move their ankles. Weight bearing was permitted once union appeared complete. There were no early complications of infection, avascular necrosis or VTE. There was one patient that had a non-clinically significant migration of a screw. Two patients were lost to follow up early due to being visitors. The mean length of follow up was 12 months in the remainder. The remaining four patients all returned to their preoperative level of activity. All had demonstrable subtalar stiffness. There was no early post-traumatic arthritis. This series represents the largest so far published. The main flaw in this report is the lack of long term follow up. While this report cannot state superiority over open techniques it is a safe, effective and acceptable technique that has significant conceptual benefits

Introduction. Tibial nerve anatomy has not been studied profoundly in comparison to Tarsal Tunnel Syndrome (TTS). Assuming symptoms are caused by an anatomical variant or mechanical cause regarding the tibial nerve, it is essential to investigate the anatomy of this structure taking in consideration that surgical and conservative treatments have shown poor results. Methods. 40 lower-leg specimens were obtained. Dissection started 20 centimeters proximal to the Dellon-McKinnon (DM) line towards the medial aspect of the naviculo-cuneiform joint distally. Anteriorly, dissection began at the tibio-talar medial gutter until the medial aspect of the Achilles tendon posteriorly. The plantar aspect extended from medial to lateral within the parameters previously described, ending at the level of the second metatarsal. Results. The flexor retinaculum had a denser consistency in 22.5% of the cases and the average length was 51.9 mm. The flexor retinaculum as an independent structure was found absent and 77.2% of cases as undistinguished extension of the crural fascia. The lateral plantar nerver (LPN) and abductor digiti minimi (ADM) nerve shared same origin in 80% of cases, 34.5% bifurcated proximal to the DM line, 31.2% distally and 34.3% at the same level. The medial calcaneal nerve (MCN) emerged proximal to the DM line in 100% of specimens. The medial plantar nerve (MPN) has its origin proximal to the DM line in 95% of cases. Conclusion. The flexor retinaculum is an extension of the crural fascia and not an independent structure. The LPN and ADM have the same origin in most cases and this presents as an important finding that must be studied in detail for clinical correlations between the motor and sensatory affections of the ADM and LPN respectively. Finally, the branches of the MCN and MPN are the most constant in their distribution and proximal origin in relation to the Dellon-McKinnon line

Background. Many approaches to management of medial malleolar fractures are described in the literature however, their morphology is under investigated. The aim of this study was to analyse the morphology of medial malleolar fractures to identify any association with medial malleolar fracture non-union or malunion. Methods. Patients who had undergone surgical fixation of their MMF were identified from 2012 to 2022, using electronic patient records in a single centre. Analysis of their preoperative, intraoperative, and postoperative radiographs was performed to determine their morphology and prevalence of non-union and malunion. Lauge-Hansen classification was used to characterise ankle fracture morphology and Herscovici classification to characterise MMF morphology. Results. A total of 650 patients were identified across a 10-year period which could be included in the study. The overall non-union rate for our cohort was 18.77% (122/650). The overall malunion rate was 6.92% (45/650). There was no significant difference in union rates across the Herscovici classification groups. Herscovici type A fractures were significantly more frequently malreduced at time of surgery as compared to other fracture types (p=.003). Medial wall blowout combined with Hercovici type B fractures showed a significant increase in malunion rate. There is a higher rate of bone union in patients who have been anatomically reduced. Conclusion. The morphology of medial malleolar fractures does have an impact of the radiological outcome following surgical management. Medial wall blowout fractures were most prevalent in adduction-type injuries; however, it should not be ruled out in rotational injuries with medial wall blowouts combined with and Herscovici type B fractures showing a significant increase in malunions. Herscovici type A fractures had significantly higher malreductions however the clinical implications of mal reducing small avulsions is unknown

Introduction. Unstable ankle fractures are routinely managed operatively. Due to soft-tissue and implant related complications, there has been recent literature reporting on the non-operative management of well-reduced medial malleolus fractures following fibular stabilisation, but with limited evidence supporting routine application. This trial assessed the superiority of internal fixation of well-reduced (displacement ≤2mm) medial malleolus fractures compared with non-fixation following fibular stabilisation. Methods and participants. Superiority, pragmatic, parallel, prospective randomised clinical trial conducted over a four year period. A total of 154 adult patients with a bi- or trimalleolar fractures were recruited from a single centre. Open injuries and vertical medial malleolar fractures were excluded. Following fibular stabilisation, patients were randomised intra-operatively on a 1:1 basis to fixation or non-fixation after satisfactory fluoroscopic fracture reduction was confirmed. The primary outcome was the Olerud Molander Ankle Score (OMAS) at one-year post-randomisation. Complications and radiographic outcomes were documented over the follow-up period. Results. Among 154 participants (mean age, 56.5 years; 119 women [77%]), 144 [94%] completed the trial. At one-year the median OMAS was 80 (IQR, 60–90) in the fixation group compared with 72.5 (IQR, 55–90) in the non-fixation group (p=0.17). Complication rates were comparable. Significantly more patients in the non-fixation group developed a radiographic non-union (20% vs 0%; p<0.001), with the majority (n=8/13) clinically asymptomatic and one patient required surgical re-intervention for this. Fracture type and reduction quality appeared to influence fracture union and patient outcome. Conclusions. In this randomised clinical trial comparing internal fixation of well-reduced medial malleolus fractures with non-fixation, following fibular stabilisation, fixation was not superior according to the primary outcome. However, 1 in 5 patients following non-fixation developed a radiographic non-union and whilst the re-intervention rate to manage this was low, the future implications require surveillance. These results may support selective non-fixation of anatomically reduced medial malleolus fractures

Introduction. Ankle fractures represent approximately 10% of the fracture workload and are projected to increase due to ageing population. We present our 5 years outcome review post-surgical management of ankle fractures in a large UK Trauma unit. Methods. A total of 111 consecutive patients treated for an unstable ankle fracture were entered into a database and prospectively followed up. Baseline patient characteristics, complications, further intervention including additional surgery, functional status were recorded during five-year follow-up. Pre-injury and post-fixation functional outcome measures at 2-years were assessed using Olerud-Molander Ankle Scores (OMAS) and Lower Extremity Functional Scales (LEFS). A p value < 0.05 was considered significant. Results. The mean age was 46 with a male:female ratio of 1:1.1. The distribution of comorbidities was BMI >30 (25%), diabetes (5%), alcohol consumption >20U/week (15%) and smoking (26%). Higher BMI was predictive of worse post-op LEFS score (p = 0.02). Between pre-injury and post fixation functional scores at 2 years, there was a mean reduction of 26.8 (OMAS) and 20.5(LEFS). Using very strict radiological criteria, 31 (28%) had less than anatomical reduction of fracture fragments intra-operatively. This was, however, not predictive of patients' functional outcome in this cohort. Within 5-year period, 22 (20%) patients had removal of metalwork from their ankle, with majority 13 (59%) requiring syndesmotic screw removal. Further interventions included: joint injection (3), deltoid reconstruction (1), arthroscopic debridement (1), superficial sinus excision (2), and conversion to hindfoot nail due to failure of fixation (1). Reduction in OMAS was predictive of patients' ongoing symptoms (p=0.01). Conclusion. There is a significant reduction in functional outcome after ankle fracture fixation and patients should be counselled appropriately. Need for removal of metalwork is higher in patients who require syndesmosis stabilisation with screw(s)

Background. Anatomical reduction of unstable Lisfranc injuries is crucial. Evidence as to the best methods of surgical stabilization remains sparse, with small patient numbers a particular issue. Dorsal bridge plating offers rigid stability and joint preservation. The primary aim of this study was to assess the medium-term functional outcomes for patients treated with this technique at our centre. Additionally, we review for risk factors that influence outcomes. Methods. 85 patients who underwent open reduction and dorsal bridge plate fixation of unstable Lisfranc injuries between January 2014 and January 2019 were identified. Metalwork was not routinely removed. A retrospective review of case notes was conducted. The Manchester-Oxford Foot Questionnaire summary index (MOXFQ-Index) was the primary outcome measure, collected at final follow-up, with a minimum follow-up of 24 months. The American Orthopedic Foot and Ankle Society (AOFAS) midfoot scale, complications, and all-cause re-operation rates were secondary outcome measures. Univariate and multivariate analyses were used to identify risk factors associated with poorer outcomes. Results. Mean follow-up 40.8 months (24–72). Mean MOXFQ-Index 27.0 (SD 7.1). Mean AOFAS score 72.6 (SD 11.6). 48/85 patients had injury patterns that included an intra-articular fracture and this was associated with poorer outcomes, with worse MOXFQ and AOFAS scores (both p < 0.001). 18 patients (21%) required the removal of metalwork for either prominence or stiffness. Female patients were more likely to require metalwork removal (OR 3.89, 95% CI 1.27 to 12.0, p = 0.02). Eight patients (9%) required secondary arthrodesis. Conclusions. This is the largest series of Lisfranc injuries treated with dorsal bridge plate fixation reported to date and the only to routinely retain metalwork. The technique is safe and effective. The presence of an intraarticular fracture is a poor prognostic indicator. Metalwork removal is more likely to be needed in female patients but routine removal may not be essential

Background. The cavovarus foot is a complex 3-dimensional deformity. Although a multitude of techniques are described for its surgical management, few of these are evidence based or guided by classification systems. Surgical management involves realignment of the hindfoot and soft tissue balancing, followed by forefoot balancing. Our aim was to classify the pattern of residual forefoot deformities once the hindfoot is corrected, to guide forefoot correction. Methods. We included 20 cavovarus feet from adult patients with Charcot-Marie-Tooth who underwent weightbearing CT (mean age 43.4 years, 14 males). Patients included had flexible deformities, with no previous surgery. Previous work established majority of rotational deformity in cavovarus feet occurs at the talonavicular joint, which is often reduced during surgery. Using specialised software (Bonelogic 2.1, Disior) a 3-dimensional, virtual model was created. Using data from normal feet as a guide, the talonavicular joint of the cavovarus feet was digitally reduced to a ‘normal’ position. Models of the corrected position were exported and geometrically analysed using Blender 3.6 to identify anatomical trends. Results. We identified 3 types of cavovarus forefoot morphotypes. Type 1 was seen in 13 cases (65%) and was defined as a foot where only the first metatarsal was relatively plantarflexed to the rest of the foot, with no significant residual adduction after talonavicular correction. Type 2 was seen in 4 cases (20%) and was defined as a foot where the second and first metatarsals were progressively plantarflexed, with no significant adduction. Type 3 was seen in 3 cases (15%) and was defined as a foot where the metatarsals were still adducted after talonavicular de-rotation. Conclusion. We classify 3 forefoot morphotypes in cavovarus feet. It is important to recognise and anticipate the residual forefoot deformities after hindfoot correction as different treatment strategies may be required for different morphotypes to achieve balanced correction

Introduction. Hindfoot intramedullary nail fixation (HFN) or fibula pro-tibial screw fixation (PTS) are surgical options for ankle fractures in patients with multiple co-morbidities; we compared their outcomes. Methods. A retrospective review of 135 patients who underwent HFN fixation (87 patients) or PTS fixation (48 patients) for ankle fractures (AO/OTA A/B/C) from 5 major trauma centres. Patient demographic data, co-morbidities, Charlson Co-morbidity Index Score (CCIS), weight-bearing, and post-operative complications were recorded. Radiographs were assessed for non-union and anatomical reduction. Results. HFN estimated 10-year survival was 27±31% and was 48±37% for PTS (p<0.001). Average time to full weightbearing (FWB) in the HFN group was 1.7±3.3 weeks compared to 7.8±3.8 weeks in the PTS group (p<0.001). Despite this, HFN fixation carried a greater VTE risk (p=0.02). HFN accompanied by joint preparation had greater risk of infection (p=0.01), metalwork failure (p=0.02) and wound breakdown (p=0.01). The overall complication rate in diabetic patients was 56%, but 76% in HFN patients. In the HFN group 17 (20%) patients died at 1 year. Patients with open fractures(p=0.01), dementia (p<0.05), and a higher CCIS (p=0.04) were more likely to die after HFN surgery. Age and co-morbidity matched data showed a higher rate of complications and mortality in those above 75 years fixed with a HFN, irrespective of CCIS. In those between 60–75 years, there was a greater risk of superficial infection and mortality after HFN, irrespective of CCIS. These complications were not seen after PTS. Conclusion. HFN carries a greater risk of superficial infections, VTE and mortality compared to PTS, independent of age and CCIS. Diabetes leads to a greater comparative risk of deep infections, wound breakdown and non-union in HFN. Alternative methods of fixation (e.g. PTS) should be considered before HFN. HFN may be suitable in selective indications where other methods are not appropriate