Varus ankle osteoarthritis (OA) is typically associated with peritalar instability, which may result in altered subtalar joint position. This study aimed to determine the extent to which total ankle replacement (TAR) in varus ankle OA can restore the subtalar position alignment using 3-dimensional semi-automated measurements on WBCT. Fourteen patients (15 ankles, mean age 61) who underwent TAR for varus ankle OA were retrospectively analyzed using semi- automated measurements of the hindfoot based on pre-and postoperative weightbearing WBCT (WBCT) imaging. Eight 3-dimensional angular measurements were obtained to quantify the ankle and subtalar joint alignment. Twenty healthy individuals were served as a control groups and were used for reliability assessments. All ankle and hindfoot angles improved between preoperative and a minimum of 1 year (mean 2.1 years) postoperative and were statistically significant in 6 out of 8 angles (P<0.05). Values The post-op angles were in a similar range to as those of healthy controls were achieved in all measurements and did not demonstrated statistical difference (P>0.05). Our findings indicate that talus repositioning after TAR within the ankle mortise improves restores the subtalar position joint alignment within normal values. These data inform foot and ankle surgeons on the amount of correction at the level of the subtalar joint that can be expected after TAR. This may contribute to improved biomechanics of the hindfoot complex. However, future studies are required to implement these findings in surgical algorithms for TAR in prescence of hindfoot deformity.

Aims

Implant failure has become more common as the number of primary total ankle arthroplasties (TAAs) performed has increased. Although revision arthroplasty has gained attention for functional preservation, the long-term results remain unclear. This study aimed to assess the long-term outcomes of revision TAA using a mobile-bearing prosthesis in a considerably large cohort; the risk factors for failure were also determined.

Several emerging reports suggest an important involvement of the hindfoot alignment in the outcome of knee osteotomy. At present, studies lack a comprehensive overview. Therefore, we aimed to systematically review all biomechanical and clinical studies investigating the role of the hindfoot alignment in the setting of osteotomies around the knee.

A systematic literature search was conducted on multiple databases combining “knee osteotomy” and “hindfoot/ankle alignment” search terms. Articles were screened and included according to the PRISMA guidelines. A quality assessment was conducted using the Quality Appraisal for Cadaveric Studies (QUACS) - and modified methodologic index for non-randomized studies (MINORS) scales.

Three cadaveric, fourteen retrospective cohort and two case-control studies were eligible for review. Biomechanical hindfoot characteristics were positively affected (n=4), except in rigid subtalar joint (n=1) or talar tilt (n=1) deformity. Patient symptoms and/or radiographic alignment at the level of the hindfoot did also improve after knee osteotomy (n=13), except in case of a small pre-operative lateral distal tibia- and hip knee ankle (HKA) angulation or in case of a large HKA correction (>14.5°). Additionally, a pre-existent hindfoot deformity (>15.9°) was associated with undercorrection of lower limb alignment following knee osteotomy. The mean QUACS score was 61.3% (range: 46–69%) and mean MINORS score was 9.2 out of 16 (range 6–12) for non-comparative and 16.5 out of 24 (range 15–18) for comparative studies.

Osteotomies performed to correct knee deformity have also an impact on biomechanical and clinical outcomes of the hindfoot. In general, these are reported to be beneficial, but several parameters were identified that are associated with newly onset – or deterioration of hindfoot symptoms following knee osteotomy. Further prospective studies are warranted to assess how diagnostic and therapeutic algorithms based on the identified criteria could be implemented to optimize the overall outcome of knee osteotomy.

Remark: Aline Van Oevelen and Arne Burssens contributed equally to this work

Aims

To assess the effect of age on clinical outcome and revision rates in patients who underwent total ankle arthroplasty (TAA) for end-stage ankle osteoarthritis (OA).

Aims

There is little information about how to manage patients with a recurvatum deformity of the distal tibia and osteoarthritis (OA) of the ankle. The aim of this study was to evaluate the functional and radiological outcome of addressing this deformity using a flexion osteotomy and to assess the progression of OA after this procedure.

Aims

Arthroscopically controlled fracture reduction in combination with percutaneous screw fixation may be an alternative approach to open surgery to treat talar neck fractures. The purpose of this study was thus to present preliminary results on arthroscopically reduced talar neck fractures.

Aims

A failed total ankle arthroplasty (TAA) is often associated with much bone loss. As an alternative to arthrodesis, the surgeon may consider a custom-made talar component to compensate for the bone loss. Our aim in this study was to assess the functional and radiological outcome after the use of such a component at mid- to long-term follow-up.

Large osteochondral lesions (OCLs) of the shoulder of the talus cannot always be treated by traditional osteochondral autograft techniques because of their size, articular geometry and loss of an articular buttress. We hypothesised that they could be treated by transplantation of a vascularised corticoperiosteal graft from the ipsilateral medial femoral condyle.

Between 2004 and 2011, we carried out a prospective study of a consecutive series of 14 patients (five women, nine men; mean age 34.8 years, 20 to 54) who were treated for an OCL with a vascularised bone graft. Clinical outcome was assessed using a visual analogue scale (VAS) for pain and the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score. Radiological follow-up used plain radiographs and CT scans to assess graft incorporation and joint deterioration.

At a mean follow-up of 4.1 years (2 to 7), the mean VAS for pain had decreased from 5.8 (5 to 8) to 1.8 (0 to 4) (p = 0.001) and the mean AOFAS hindfoot score had increased from 65 (41 to 70) to 81 (54 to 92) (p = 0.003). Radiologically, the talar contour had been successfully reconstructed with stable incorporation of the vascularised corticoperiosteal graft in all patients. Joint degeneration was only seen in one ankle.

Treatment of a large OCL of the shoulder of the talus with a vascularised corticoperiosteal graft taken from the medial condyle of the femur was found to be a safe, reliable method of restoring the contour of the talus in the early to mid-term.

Cite this article: Bone Joint J 2015;97-B:1242–9.

Talonavicular and subtalar joint fusion through a medial incision (modified triple arthrodesis) has become an increasingly popular technique for treating symptomatic flatfoot deformity caused by posterior tibial tendon dysfunction.

The purpose of this study was to look at its clinical and radiological mid- to long-term outcomes, including the rates of recurrent flatfoot deformity, nonunion and avascular necrosis of the dome of the talus.

A total of 84 patients (96 feet) with a symptomatic rigid flatfoot deformity caused by posterior tibial tendon dysfunction were treated using a modified triple arthrodesis. The mean age of the patients was 66 years (35 to 85) and the mean follow-up was 4.7 years (1 to 8.3). Both clinical and radiological outcomes were analysed retrospectively.

In 86 of the 95 feet (90.5%) for which radiographs were available, there was no loss of correction at final follow-up. In all, 14 feet (14.7%) needed secondary surgery, six for nonunion, two for avascular necrosis, five for progression of the flatfoot deformity and tibiotalar arthritis and one because of symptomatic overcorrection. The mean American Orthopaedic Foot and Ankle Society Hindfoot score (AOFAS score) at final follow-up was 67 (between 16 and 100) and the mean visual analogue score for pain 2.4 points (between 0 and 10).

In conclusion, modified triple arthrodesis provides reliable correction of deformity and a good clinical outcome at mid- to long-term follow-up, with nonunion as the most frequent complication. Avascular necrosis of the talus is a rare but serious complication of this technique.

Cite this article: Bone Joint J 2015; 97-B:668–74.

The treatment of peri-prosthetic joint infection (PJI) of the ankle is not standardised. It is not clear whether an algorithm developed for hip and knee PJI can be used in the management of PJI of the ankle. We evaluated the outcome, at two or more years post-operatively, in 34 patients with PJI of the ankle, identified from a cohort of 511 patients who had undergone total ankle replacement. Their median age was 62.1 years (53.3 to 68.2), and 20 patients were women. Infection was exogenous in 28 (82.4%) and haematogenous in six (17.6%); 19 (55.9%) were acute infections and 15 (44.1%) chronic. Staphylococci were the cause of 24 infections (70.6%). Surgery with retention of one or both components was undertaken in 21 patients (61.8%), both components were replaced in ten (29.4%), and arthrodesis was undertaken in three (8.8%). An infection-free outcome with satisfactory function of the ankle was obtained in 23 patients (67.6%). The best rate of cure followed the exchange of both components (9/10, 90%). In the 21 patients in whom one or both components were retained, four had a relapse of the same infecting organism and three had an infection with another organism. Hence the rate of cure was 66.7% (14 of 21). In these 21 patients, we compared the treatment given to an algorithm developed for the treatment of PJI of the knee and hip. In 17 (80.9%) patients, treatment was not according to the algorithm. Most (11 of 17) had only one criterion against retention of one or both components. In all, ten of 11 patients with severe soft-tissue compromise as a single criterion had a relapse-free survival. We propose that the treatment concept for PJI of the ankle requires adaptation of the grading of quality of the soft tissues.

Cite this article: Bone Joint J 2014;96-B:772–7.

We undertook a prospective study to analyse the outcome of 48 malunited pronation-external rotation fractures of the ankle in 48 patients (25 females and 23 males) with a mean age of 45 years (21 to 69), treated by realignment osteotomies. The interval between the injury and reconstruction was a mean of 20.2 months (3 to 98).

In all patients, valgus malalignment of the distal tibia and malunion of the fibula were corrected. In some patients, additional osteotomies were performed. Patients were reviewed regularly, and the mean follow-up was 7.1 years (2 to 15).

Good or excellent results were obtained in 42 patients (87.5%) with the benefit being maintained over time. Congruent ankles without a tilted talus (Takakura stage 0 and 1) were obtained in all but five cases. One patient required total ankle replacement.

It has been suggested that a supramalleolar osteotomy can return the load distribution in the ankle joint to normal. However, due to the lack of biomechanical data, this supposition remains empirical. The purpose of this biomechanical study was to determine the effect of simulated supramalleolar varus and valgus alignment on the tibiotalar joint pressure, in order to investigate its relationship to the development of osteoarthritis. We also wished to establish the rationale behind corrective osteotomy of the distal tibia.

We studied 17 cadaveric lower legs and quantified the changes in pressure and force transfer across the tibiotalar joint for various degrees of varus and valgus deformity in the supramalleolar area. We assumed that a supramalleolar osteotomy which created a varus deformity of the ankle would result in medial overload of the tibiotalar joint. Similarly, we thought that creating a supramalleolar valgus deformity would cause a shift in contact towards the lateral side of the tibiotalar joint. The opposite was observed. The restricting role of the fibula was revealed by carrying out an osteotomy directly above the syndesmosis. In end-stage ankle osteoarthritis with either a valgus or varus deformity, the role of the fibula should be appreciated and its effect addressed where appropriate.

The aim of this study was to identify the incidence of post-operative symptomatic deep-vein thrombosis (DVT), as well as the risk factors for and location of DVT, in 665 patients (701 ankles) who underwent primary total ankle replacement. All patients received low-molecular-weight heparin prophylaxis. A total of 26 patients (3.9%, 26 ankles) had a symptomatic DVT, diagnosed by experienced radiologists using colour Doppler ultrasound. Most thrombi (22 patients, 84.6%) were localised distally in the operated limb. Using a logistic multiple regression model we identified obesity, a previous venous thromboembolic event and the absence of full post-operative weight-bearing as independent risk factors for developing a symptomatic DVT.

The incidence of symptomatic DVT after total ankle replacement and use of low-molecular-weight heparin is comparable with that in patients undergoing total knee or hip replacement.

The aim of this study was to compare the outcome of bilateral sequential total ankle replacement (TAR) with that of unilateral TAR. We reviewed 23 patients who had undergone sequential bilateral TAR under a single anaesthetic and 46 matched patients with a unilateral TAR. There were no significant pre-operative differences between the two groups in terms of age, gender, body mass index, American Society of Anaesthesiologists classification and aetiology of the osteoarthritis of the ankle. Clinical and radiological follow-up was carried out at four months, one and two years.

After four months, patients with simultaneous bilateral TAR reported a significantly higher mean pain score than those with a unilateral TAR. The mean American Orthopaedic Foot and Ankle Society hindfoot score and short-form 36 physical component summary score were better in the unilateral group. However, this difference disappeared at the one-and two-year follow-ups.

Bilateral sequential TAR under one anaesthetic can be offered to patients with bilateral severe ankle osteoarthritis. However, they should be informed of the long recovery period.

We report the clinical and radiological outcome of total ankle replacement performed in conjunction with hindfoot fusion or in isolation. Between May 2003 and June 2008, 60 ankles were treated with total ankle replacement with either subtalar or triple fusion, and the results were compared with a control group of 288 ankles treated with total ankle replacement alone.

After the mean follow-up of 39.5 months (12 to 73), the ankles with hindfoot fusion showed significant improvement in the mean visual analogue score for pain (p < 0.001), the mean American Orthopaedic Foot and Ankle Society score (p < 0.001), and the mean of a modified version of this score (p < 0.001). The mean visual analogue pain score (p = 0.304) and mean modified American Orthopaedic Foot and Ankle Society score (p = 0.119) were not significantly different between the hindfoot fusion and the control groups. However, the hindfoot fusion group had a significantly lower mean range of movement (p = 0.009) and a higher rate of posterior focal osteolysis (p = 0.04). Both groups showed various complications (p = 0.131) and failure occurring at a similar rate (p = 0.685).

Subtalar or triple fusion is feasible and has minimal adverse effects on ankles treated with total ankle replacement up to midterm follow-up. The clinical outcome of total ankle replacement when combined with hindfoot fusion is comparable to that of ankle replacement alone. Thus, hindfoot fusion should be performed in conjunction with total ankle replacement when indicated.

Introduction: Recent studies suggest that preservation of the calcaneocuboidal joint and a single medial approach may lead to equally good results as a conventional triple arthrodesis for painful malalignment or arthritis of the hindfoot. The theoretical advantage of a single medial approach for subtalar and talonavicular fusion is a lower risk for postoperative wound healing problems. The aim of our study was to assess the capability of the modified triple arthrodesis to correct hindfoot malalignment.

Methods: We retrospectively measured radiological parameters in 36 consecutive feet in 34 patients who underwent a modified triple arthrodesis. All operations were done with a single medial incision using rigid internal fixation with screws. Radiological evaluation was done at a mean of 15 months (range 6 to 34) postoperatively.

Results: The following angles showed a significant (p< 0.001) improvement: the talonavicular coverage from 23° (range,−51 to 51°) to 10° (range, −13 to 32°), the dorsoplantar talar-first metatarsal angle from 18° (range, −19 to 76°) to 9° (range, −11 to 28°), the lateral talo-calcaneal angle from 38° (range, 14 to 57°) to 28° (range, 12 to 44°), and the lateral talar-first metatarsal angle from −15° (range, −51 to 23°) to −4°(range, −18 to 22°). We encountered neither primary wound healing problems, nor bony nonunion.

Conclusions: In our study all radiological parameters improved postoperatively. We therefore believe that this is a safe and effective technique in the management of hindfoot deformity with predictable outcome even in patients with severe malalignment.

Background: While several studies in the last years tried to identify clinical limitations of patients suffering from end-stage ankle osteoarthritis (OA), very few attempted to assess foot and ankle function in a more objective biomechanical way, especially using dynamic pedobarography. The aim of the study was therefore to explore plantar pressure distribution characteristics in a large cohort of posttraumatic end-stage ankle OA.

Method: 120 patients (female, 54; male, 66; 120 cases) suffering from posttraumatic end-stage ankle OA were included. The clinical examination consisted of assessment of the AOFAS hindfoot score, a pain score, the range of motion (ROM) for ankle dorsiflexion and plantar flexion, and the body mass index (BMI, kg/m2). Radiological parameters included the radiological tibiotalar alignment and the radiological ankle OA grading. Plantar pressure distribution parameters were assessed using dynamic pedobarography.

Results: Intra-individual comparison between the affected and the opposite, asymptomatic ankle revealed significant differences for several parameters: maximum pressure force and contact area were decreased in the whole OA foot, such was maximum peak pressure in the hindfoot and toes area. No correlations could be found between clinical parameters, such as AOFAS hindfoot score, VAS for pain, and ROM, and the pedobarographic data. However, there was a positive correlation between dorsiflexion and the pedobarographic parameters for the hindfoot area.

Conclusion: In conclusion, posttraumatic end-stage ankle OA leads to significant alterations in plantar pressure distribution. These might be interpreted as an attempt of the patient to reduce the load on the painful ankle. Other explanations might be bony deformity and ankle malalignment as a consequence of either the initial trauma or of the degenerative process itself, pain related disuse atrophy of surrounding muscles, and scarred soft tissue.

Background: The diagnosis of implant-associated infections is difficult due to organisms attached to surfaces as biofilms. We hypothesize that diagnosis can be improved by removing biofilm microorganisms from implant surface by sonication, followed by Gram stain, culture and calorimetric detection in sonication fluid.

Methods: We prospectively included adult patients from May 2005 until December 2006 from whom an orthopedic implant (joint prosthesis or internal fixation device) was removed for any reason. Removed implants were vortexed and sonicated in solid containers 5 min at 40 kHz in 100 to 400 ml Ringer’s solution. The resulting sonicate was plated and incubated on aerobic and anaerobic blood agar and aliquots were in parallel incubated at 37°C for 3 days in an isothermal calorimeter TAM III (TA Instruments, New Castle, DE). Gram stain was performed on sonicates centrifuged at 5000 g for 10 min. Definitive infection diagnosis was of the implant was defined if purulence surrounding the implant, or growth of the same microorganism in ≥2 synovial fluid or intraoperative tissue specimens, or acute inflammation in histopathology, or a sinus tract was present. Sonicate culture was defined positive if > 10 cfu (colony forming units) grew/ml sonicate. Calorimetry was defined positive if heat flow rate increased ≥10 μW above baseline (detection limit ~0.3 μW).

Results: 846 implants (367 joint prostheses and 479 internal fixation devices) were studied, of which 171 (20%) were infected and 675 (80%) were aseptic cases. The sensitivity of intraoperative tissue cultures was 74%, of sonicate culture 89%, of sonicate Gram stain 51%, of sonicate calorimetry 96%. The specificity of all specimens was ≥95%.

Conclusion: Sonicate culture and calorimetry were more sensitive than intraoperative tissue cultures for diagnosing implant infections. With Gram stain of centrifuged sonicate, infection was diagnosed in > 50% cases. Sonicate culture and calorimetry may replace the current approach using multiple intraoperative periprosthetic tissue specimens, whenever the implant or part of it is removed.

Introduction: Ankle sprains are among the most common injuries in sports and recreational activities. 10 to 40% of the acute ankle sprains lead to chronic ankle instability (CAI), which can be divided into its mechanical and its functional division. The clinical-orthopaedic diagnosis of mechanical ankle instability (MAI) has been well established, whereas the etiology of the functional ankle instability (FAI) is still not objectively allocatable. The aim of this study was to identify neuromuscular patterns in lower leg muscles to objectively describe the FAI.

Methods: 15 patients suffering from unilateral CAI (mean age, 35.5 years) since 2.4 years (1–9 years) were examined. The patients were evaluated etiologically and clinically (VAS pain score, AOFAS Ankle Score, calf circumference, and SF-36). Electromyographic (EMG) measurements of surface EMG with determination of mean EMG frequency and intensity by wavelet transformation were taken synchronously with dynamic stabilometry measurements. Four lower leg muscles were detected: tibialis anterior (TA), gastrocnemius medialis (GM), soleus (SO), and peroneus longus (PL) muscle. 15 healthy subjects were tested identically.

Results: Patients showed higher stability indices, higher VAS score, and lower AOFAS Ankle Score.

The mean EMG frequency was significantly lower for the PL (pathologic leg, 138.3 Hz; normal leg, 158.3 Hz, p< 0.001). Lower mean EMG intensity was found in the pathologic PL and GM. The mean EMG frequency of the TA was lower in the patient group, its intensity higher.

Discusssion and conclusion: Patients suffering CAI demonstrate weakened stability and impaired life quality. Neuromuscular patterns of the GM, PL and TA lead evidently to an objective etiology of the functional ankle instability. EMG patterns of four lower leg muscles indicate chronic changes in muscle morphology, such as degradation of type-II muscle fibres or modified velocity of motor unit action potentials. Accurate prevention and rehabilitation may compensate a MAI with a sufficient functional potential of lower leg muscles. This may also avoid operative treatment of MAI. The present study evidences the etiology of the FAI with objective parameters and indicates chronic changes in muscle morphology within CAI-Patients.

Purpose: Ankle sprains are among the most common injuries in sports and recreational activities. 10 to 40% of the acute ankle sprains lead to chronic ankle instability (CAI), which can be divided into its mechanical and its functional division. The clinical-orthopaedic diagnosis of mechanical ankle instability (MAI) has been well established, whereas the etiology of the functional ankle instability (FAI) is still not objectively allocatable. The aim of this study was to identify neuromuscular patterns in lower leg muscles to objectively describe the FAI.

Method: 15 patients suffering from unilateral CAI (mean age, 35.5 years) since 2.4 years (1–9 years) were examined. The patients were evaluated etiologically and clinically (VAS pain score, AOFAS Ankle Score, calf circumference, and SF-36). Electromyographic (EMG) measurements of surface EMG with determination of mean EMG frequency and intensity by wavelet transformation were taken synchronously with dynamic stabilometry measurements. Four lower leg muscles were detected: tibialis anterior (TA), gastrocnemius medialis (GM), soleus (SO), and peroneus longus (PL) muscle. 15 healthy subjects were tested identically.

Results: Patients showed higher stability indices, higher VAS score, and lower AOFAS Ankle Score. The mean EMG frequency was significantly lower for the PL (pathologic leg, 138.3 Hz; normal leg, 158.3 Hz, p< 0.001). Lower mean EMG intensity was found in the pathologic PL and GM. The mean EMG frequency of the TA was lower in the patient group, its intensity higher.

Conclusion: Patients suffering CAI demonstrate weakened stability and impaired life quality. Neuromuscular patterns of the GM, PL and TA lead evidently to an objective etiology of the functional ankle instability. EMG patterns of four lower leg muscles indicate chronic changes in muscle morphology, such as degradation of type-II muscle fibres or modified velocity of motor unit action potentials. Accurate prevention and rehabilitation may compensate a MAI with a sufficient functional potential of lower leg muscles. This may also avoid operative treatment of MAI. The present study evidences the etiology of the FAI with objective parameters and indicates chronic changes in muscle morphology within CAI-Patients.