Aims. The rationale for exacting restoration of skeletal anatomy after unstable ankle fracture is to improve outcomes by reducing complications from malunion; however, current definitions of malunion lack confirmatory clinical evidence. Methods. Radiological (absolute radiological measurements aided by computer software) and clinical (clinical interpretation of radiographs) definitions of malunion were compared within the Ankle Injury Management (AIM) trial cohort, including people aged ≥ 60 years with an unstable ankle fracture. Linear regressions were used to explore the relationship between radiological malunion (RM) at six months and changes in function at three years. Function was assessed with the Olerud-Molander Ankle Score (OMAS), with a minimal clinically important difference set as six points, as per the AIM trial. Piecewise linear models were used to investigate new radiological thresholds which better explain symptom impact on ankle function. Results. Previously described measures of RM and surgeon opinion of clinically significant malunion (CSM) were shown to be related but with important differences. CSM was more strongly related to outcome (-13.9 points on the OMAS; 95% confidence interval (CI) -21.9 to -5.4) than RM (-5.5 points; 95% CI -9.8 to -1.2). Existing malunion thresholds for talar
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
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. This is a single-centre retrospective review of patients who underwent primary total ankle arthroplasty (TAA) with a Vantage implant between November 2017 and February 2020, with a minimum of two years’ follow-up. Four surgeons contributed patients. The primary outcome was reoperation and revision rate of the Vantage implant at two years. Secondary outcomes included radiological alignment, peri-implant complications, and pre- and postoperative patient-reported outcomes.Aims
Methods
Objectives. To evaluate the applicability of MRI for the quantitative assessment
of anterior talofibular ligaments (ATFLs) in symptomatic chronic
ankle instability (CAI). Methods. Between 1997 and 2010, 39 patients with symptomatic CAI underwent
surgical treatment (22 male, 17 female, mean age 25.4 years (15
to 40)). In all patients, the maximum diameters of the ATFLs were
measured on pre-operative T2-weighted MR images in planes parallel
to the path of the ATFL. They were classified into three groups based
on a previously published method with modifications: ‘normal’, diameter
= 1.0 - 3.2 mm; ‘thickened’, diameter >
3.2 mm; ‘thin or absent’,
diameter <
1.0 mm. Stress radiography was performed with the
maximum manual force in inversion under general anaesthesia immediately
prior to surgery. In surgery, ATFLs were macroscopically divided
into two categories: ‘thickened’, an obvious thickened ligament
and ‘thin or absent’. The imaging results were compared with the
macroscopic results that are considered to be of a gold standard. Results. Agreement was reached when comparison was made between groups,
based on MRI and macroscopic findings. ATFLs were abnormal in all
39 cases and classified as ten ‘thickened’ and 29 ‘thin or absent’.
As to talar
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. 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.Aims
Methods
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
Preoperative talar valgus deformity ≥ 15° is considered a contraindication for total ankle arthroplasty (TAA). We compared operative procedures and clinical outcomes of TAA in patients with talar valgus deformity ≥ 15° and < 15°. A matched cohort of patients similar for demographics and components used but differing in preoperative coronal-plane tibiotalar valgus deformity ≥ 15° (valgus, n = 50; 52% male, mean age 65.8 years (SD 10.3), mean body mass index (BMI) 29.4 (SD 5.2)) or < 15° (control, n = 50; 58% male, mean age 65.6 years (SD 9.8), mean BMI 28.7 (SD 4.2)), underwent TAA by one surgeon. Preoperative and postoperative radiographs, Ankle Osteoarthritis Scale (AOS) pain and disability and 36-item Short Form Health Survey (SF-36) version 2 scores were collected prospectively. Ancillary procedures, secondary procedures, and complications were recorded.Aims
Methods
The purpose of this study is to examine the adductus impact on the second metatarsal by the nonosteotomy nonarthrodesis syndesmosis procedure for the hallux valgus deformity correction, and how it would affect the mechanical function of the forefoot in walking. For correcting the metatarsus primus varus deformity of hallux valgus feet, the syndesmosis procedure binds first metatarsal to the second metatarsal with intermetatarsal cerclage sutures. We reviewed clinical records of a single surgical practice from its entire 2014 calendar year. In total, 71 patients (121 surgical feet) qualified for the study with a mean follow-up of 20.3 months (SD 6.2). We measured their metatarsus adductus angle with the Sgarlato’s method (SMAA), and the intermetatarsal angle (IMA) and metatarsophalangeal angle (MPA) with Hardy’s mid axial method. We also assessed their American Orthopaedic Foot & Ankle Society (AOFAS) clinical scale score, and photographic and pedobarographic images for clinical function results.Aims
Methods
Tibiotalocalcaneal (TTC) fusion is used to treat a variety of conditions affecting the ankle and subtalar joint, including osteoarthritis (OA), Charcot arthropathy, avascular necrosis (AVN) of the talus, failed total ankle arthroplasty, and severe deformity. The prevalence of postoperative complications remains high due to the complexity of hindfoot disease seen in these patients. The aim of this study was to analyze the relationship between preoperative conditions and postoperative complications in order to predict the outcome following primary TTC fusion. We retrospectively reviewed the medical records of 101 patients who underwent TTC fusion at the same institution between 2011 and 2019. Risk ratios (RRs) associated with age, sex, diabetes, cardiovascular disease, smoking, preoperative ankle deformity, and the use of bone graft during surgery were related to the postoperative complications. We determined from these data which pre- and perioperative factors significantly affected the outcome.Aims
Methods
To evaluate the donor site morbidity and tendon morphology after harvesting whole length, full-thickness peroneus longus tendon (PLT) proximal to the lateral malleolus for ligament reconstructions or tendon transfer. A total of 21 eligible patients (mean age 34.0 years (standard deviation (SD) 11.2); mean follow-up period 31.8 months (SD 7.7), and 12 healthy controls (mean age, 26.8 years (SD 5.9) were included. For patients, clinical evaluation of the donor ankle was performed preoperatively and postoperatively. Square hop test, ankle strength assessment, and MRI of distal calf were assessed bilaterally in the final follow-up. The morphological symmetry of peroneal tendons bilaterally was evaluated by MRI in healthy controls.Aims
Methods
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. A total of 39 patients (12 women, 27 men; mean age 47 years (28 to 72)) with a distal tibial recurvatum deformity were treated with a flexion osteotomy, between 2010 and 2015. Nine patients (23%) subsequently required conversion to either a total ankle arthroplasty (seven) or an arthrodesis (two) after a mean of 21 months (9 to 36). A total of 30 patients (77%), with a mean follow-up of 30 months (24 to 76), remained for further evaluation. Functional outcome, sagittal ankle joint OA using a modified Kellgren and Lawrence Score, tibial lateral surface (TLS) angle, and talar offset ratio (TOR) were evaluated on pre- and postoperative weight-bearing radiographs.Aims
Patients and Methods
The aim of this study was to present a series of patients with
aseptic failure of a total ankle arthroplasty (TAA) who were treated
with fusion of the hindfoot using a nail. A total of 23 TAAs, in 22 patients, were revised for aseptic
loosening and balloon osteolysis to a hindfoot fusion by a single
surgeon (NH) between January 2012 and August 2014. The procedure
was carried out without bone graft using the Phoenix, Biomet Hindfoot
Arthrodesis Nail. Preoperative investigations included full blood
count, CRP and ESR, and radiological investigations including plain
radiographs and CT scans. Postoperative plain radiographs were assessed
for fusion. When there was any doubt, CT scans were performed.Aims
Patients and Methods
Hindfoot arthrodesis with retrograde intramedullary nailing has
been described as a surgical strategy to reconstruct deformities
of the ankle and hindfoot in patients with Charcot arthropathy.
This study presents case series of Charcot arthropathy patients
treated with two different retrograde intramedullary straight compression
nails in order to reconstruct the hindfoot and assess the results
over a mid-term follow-up. We performed a retrospective analysis of 18 consecutive patients
and 19 operated feet with Charcot arthropathy who underwent a hindfoot
arthrodesis using a retrograde intramedullary compression nail.
Patients were ten men and eight women with a mean age of 63.43 years
(38.5 to 79.8). We report the rate of limb salvage, complications requiring
additional surgery, and fusion rate in both groups. The mean duration
of follow-up was 46.36 months (37 to 70).Aims
Patients and Methods
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:
Sporting injuries around the ankle vary from
simple sprains that will resolve spontaneously within a few days
to severe injuries which may never fully recover and may threaten
the career of a professional athlete. Some of these injuries can
be easily overlooked altogether or misdiagnosed with potentially
devastating effects on future performance. In this review article,
we cover some of the common and important sporting injuries involving
the ankle including updates on their management and outcomes. Cite this article:
The purpose of this study was to compare the clinical and radiographic
outcomes of total ankle arthroplasty (TAA) in patients with pre-operatively
moderate and severe arthritic varus ankles to those achieved for
patients with neutral ankles. A total of 105 patients (105 ankles), matched for age, gender,
body mass index, and follow-up duration, were divided into three
groups by pre-operative coronal plane tibiotalar angle; neutral
(<
5°), moderate (5° to 15°) and severe (>
15°) varus deformity.
American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot
score, a visual analogue scale (VAS), and Short Form (SF)-36 score
were used to compare the clinical outcomes after a mean follow-up period
of 51 months (24 to 147).Aims
Patients and Methods
Most posterior hindfoot procedures have been
described with the patient positioned prone. This affords excellent access
to posterior hindfoot structures but has several disadvantages for
the management of the airway, the requirement for an endotracheal
tube in all patients, difficulty with ventilation and an increased
risk of pressure injuries, especially with regard to reduced ocular
perfusion. We describe use of the ‘recovery position’, which affords equivalent
access to the posterior aspect of the ankle and hindfoot without
the morbidity associated with the prone position. A laryngeal mask
rather than endotracheal tube may be used in most patients. In this
annotation we describe this technique, which offers a safe and simple alternative
method of positioning patients for posterior hindfoot and ankle
surgery. Cite this article:
Our study describes the clinical outcome of total ankle replacement (TAR) performed in patients with moderate to severe varus deformity. Between September 2004 and September 2007, 23 ankles with a varus deformity ≥ 10° and 22 with neutral alignment received a TAR. Following specific algorithms according to joint congruency, the varus ankles were managed by various additional procedures simultaneously with TAR. After a mean follow-up of 27 months (12 to 47), the varus ankles improved significantly in all clinical measures (p <
0.0001 for visual analogue scale and American Orthopaedic Foot and Ankle Society score, p = 0.001 for range of movement). No significant differences were found between the varus and neutral groups regarding the clinical (p = 0.766 for visual analogue scale, p = 0.502 for American Orthopaedic Foot and Ankle Society score, p = 0.773 for range of movement) and radiological outcome (p = 0.339 for heterotopic ossification, p = 0.544 for medial cortical reaction, p = 0.128 for posterior focal osteolysis). Failure of the TAR with conversion to an arthrodesis occurred in one case in each group. The clinical outcome of TAR performed in ankles with pre-operative varus alignment ≥ 10° is comparable with that of neutrally aligned ankles when appropriate additional procedures to correct the deformity are carried out simultaneously with TAR.
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:
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.
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.
Moderate to severe hallux valgus is conventionally
treated by proximal metatarsal osteotomy. Several recent studies
have shown that the indications for distal metatarsal osteotomy
with a distal soft-tissue procedure could be extended to include
moderate to severe hallux valgus. The purpose of this prospective randomised controlled trial was
to compare the outcome of proximal and distal Chevron osteotomy
in patients undergoing simultaneous bilateral correction of moderate
to severe hallux valgus. The original study cohort consisted of 50 female patients (100
feet). Of these, four (8 feet) were excluded for lack of adequate
follow-up, leaving 46 female patients (92 feet) in the study. The
mean age of the patients was 53.8 years (30.1 to 62.1) and the mean
duration of follow-up 40.2 months (24.1 to 80.5). After randomisation,
patients underwent a proximal Chevron osteotomy on one foot and
a distal Chevron osteotomy on the other. At follow-up, the American Orthopedic Foot and Ankle Society
(AOFAS) hallux metatarsophalangeal interphalangeal (MTP-IP) score,
patient satisfaction, post-operative complications, hallux valgus
angle, first-second intermetatarsal angle, and tibial sesamoid position
were similar in each group. Both procedures gave similar good clinical
and radiological outcomes. This study suggests that distal Chevron osteotomy with a distal
soft-tissue procedure is as effective and reliable a means of correcting
moderate to severe hallux valgus as proximal Chevron osteotomy with
a distal soft-tissue procedure. Cite this article:
The main object of this study was to use a geometric morphometric
approach to quantify the left-right symmetry of talus bones. Analysis was carried out using CT scan images of 11 pairs of
intact tali. Two important geometric parameters, volume and surface
area, were quantified for left and right talus bones. The geometric
shape variations between the right and left talus bones were also
measured using deviation analysis. Furthermore, location of asymmetry
in the geometric shapes were identified. Numerical results showed that talus bones are bilaterally symmetrical
in nature, and the difference between the surface area of the left
and right talus bones was less than 7.5%. Similarly, the difference
in the volume of both bones was less than 7.5%. Results of the three-dimensional
(3D) deviation analyses demonstrated the mean deviation between
left and right talus bones were in the range of -0.74 mm to 0.62
mm. It was observed that in eight of 11 subjects, the deviation
in symmetry occurred in regions that are clinically less important
during talus surgery. Objective
Methods
Results
Severe hallux valgus deformity is conventionally
treated with proximal metatarsal osteotomy. Distal metatarsal osteotomy
with an associated soft-tissue procedure can also be used in moderate
to severe deformity. We compared the clinical and radiological outcomes
of proximal and distal chevron osteotomy in severe hallux valgus deformity
with a soft-tissue release in both. A total of 110 consecutive female
patients (110 feet) were included in a prospective randomised controlled
study. A total of 56 patients underwent a proximal procedure and
54 a distal operation. The mean follow-up was 39 months (24 to 54)
in the proximal group and 38 months (24 to 52) in the distal group.
At follow-up the hallux valgus angle, intermetatarsal angle, distal
metatarsal articular angle, tibial sesamoid position, American Orthopaedic
Foot and Ankle Society (AOFAS) hallux metatarsophalangeal-interphalangeal
score, patient satisfaction level, and complications were similar
in each group. Both methods showed significant post-operative improvement
and high levels of patient satisfaction. Our results suggest that
the distal chevron osteotomy with an associated distal soft-tissue
procedure provides a satisfactory method for correcting severe hallux
valgus deformity. Cite this article:
We investigated 60 patients (89 feet) with a
mean age of 64 years (61 to 67) treated for congenital clubfoot deformity,
using standardised weight-bearing radiographs of both feet and ankles
together with a functional evaluation. Talocalcaneal and talonavicular
relationships were measured and the degree of osteo-arthritic change
in the ankle and talonavicular joints was assessed. The functional
results were evaluated using a modified Laaveg-Ponseti score. The
talocalcaneal (TC) angles in the clubfeet were significantly lower
in both anteroposterior (AP) and lateral projections than in the
unaffected feet (p <
0.001 for both views). There was significant
medial subluxation of the navicular in the clubfeet compared with
the unaffected feet (p <
0.001). Severe osteoarthritis in the
ankle joint was seen in seven feet (8%) and in the talonavicular
joint in 11 feet (12%). The functional result was excellent or good
(≥ 80 points) in 29 patients (48%), and fair or poor (<
80 points)
in 31 patients (52%). Patients who had undergone few (0 to 1) surgical
procedures had better functional outcomes than those who had undergone
two or more procedures (p <
0.001). There was a significant correlation
between the functional result and the degree of medial subluxation
of the navicular (p <
0.001, r2 = 0.164), the talocalcaneal
angle on AP projection (p <
0.02, r2 = 0.025) and extent of osteoarthritis
in the ankle joint (p <
0.001). We conclude that poor functional outcome in patients with congenital
clubfoot occurs more frequently in those with medial displacement
of the navicular, osteoarthritis of the talonavicular and ankle
joints, and a low talocalcaneal angle on the AP projection, and
in patients who have undergone two or more surgical procedures. However,
the ankle joint in these patients appeared relatively resistant
to the development of osteoarthritis.
Metatarsalgia is a recognised complication following iatrogenic shortening of the first metatarsal in the management of hallux valgus. The traditional surgical treatment is by shortening osteotomies of the lesser metatarsals. We describe the results of lengthening of iatrogenic first brachymetatarsia in 16 females. A Scarf-type osteotomy was used in the first four cases and a step-cut of equal thicknesses along the axis of the first metatarsal was performed in the others. The mean follow-up was 21 months (19 to 26). Relief of metatarsalgia was obtained in the six patients in whom 10 mm of lengthening had been achieved, compared to only 50% relief in those where less than 8 mm of lengthening had been gained. One-stage step-cut lengthening osteotomy of the first metatarsal may be preferable to shortening osteotomies of the lesser metatarsals in the treatment of metatarsalgia following surgical shortening of the first metatarsal.
We present the outcomes in 38 consecutive patients who had total ankle replacement using the Ankle Evolution System with a minimum follow-up of four years. Pain and function were assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) score and regular standardised anteroposterior and lateral weight-bearing radiographs were obtained. Patient satisfaction and complications were recorded and the survival of the implants was demonstrated by the Kaplan-Meier method. The mean follow-up was for 57.8 months (48 to 80). The cumulative survival rate at six years was 94.7% (95% confidence interval 80.3 to 98.7). The mean total AOFAS score was 88.1 (53 to 100). The mean score for pain was 35.8 (20 to 40). Ten patients presented with edge-loading of whom nine had corrective surgery. Two ankles were revised, one to an arthrodesis and the other to replace the tibial component. Nine patients showed radiological evidence of osteolysis. They had minimal non-progressive symptoms and further surgery was not undertaken. Nevertheless, the concerns about osteolysis led to the implant being withdrawn by the manufacturer. The medium-term results of the ankle evolution system ankle replacement are satisfactory with high patient satisfaction, but the rate of osteolysis is of some concern. The long-term benefit of this procedure has yet to be determined.
Hallux rigidus was first described in 1887. Many aetiological factors have been postulated, but none has been supported by scientific evidence. We have examined the static and dynamic imbalances in the first metatarsophalangeal joint which we postulated could be the cause of this condition. We performed a finite-element analysis study on a male subject and calculated a mathematical model of the joint when subjected to both normal and abnormal physiological loads. The results gave statistically significant evidence for an increase in tension of the plantar fascia as the cause of abnormal stress on the articular cartilage rather than mismatch of the articular surfaces or subclinical muscle contractures. Our study indicated a clinical potential cause of hallux rigidus and challenged the many aetiological theories. It could influence the choice of surgical procedure for the treatment of early grades of hallux rigidus.