Aims

As an alternative to external fixators, intramedullary lengthening nails (ILNs) can be employed for distraction osteogenesis. While previous studies have demonstrated that typical complications of external devices, such as soft-tissue tethering, and pin site infection can be avoided with ILNs, there is a lack of studies that exclusively investigated tibial distraction osteogenesis with motorized ILNs inserted via an antegrade approach.

Aims

This study reports updates the previously published two-year clinical, functional, and radiological results of a group of patients who underwent transfibular total ankle arthroplasty (TAA), with follow-up extended to a minimum of five years.

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, r. 2 . = 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

A total of 38 relapsed congenital clubfeet (16 stiff, 22 partially correctable) underwent revision of soft-tissue surgery, with or without a bony procedure, and transfer of the tendon of tibialis anterior at a mean age of 4.8 years (2.0 to 10.1). The tendon was transferred to the third cuneiform in five cases, to the base of the third metatarsal in ten and to the base of the fourth in 23. The patients were reviewed at a mean follow-up of 24.8 years (10.8 to 35.6). A total of 11 feet were regarded as failures (one a tendon failure, five with a subtalar fusion due to over-correction, and five with a triple arthrodesis due to under-correction or relapse).

In the remaining feet the clinical outcome was excellent or good in 20 and fair or poor in seven. The mean Laaveg-Ponseti score was 81.6 of 100 points (52 to 92). Stiffness was mild in four feet and moderate or severe in 23.

Comparison between the post-operative and follow-up radiographs showed statistically significant variations of the talo-first metatarsal angle towards abduction. Variations of the talocalcaneal angles and of the overlap ratio were not significant.

Extensive surgery for relapsed clubfoot has a high rate of poor long-term results. The addition of transfer of the tendon of tibialis anterior can restore balance and may provide some improvement of forefoot adduction. However, it has a considerable complication rate, including failure of transfer, over-correction, and weakening of dorsiflexion. The procedure should be reserved for those limited cases in which muscle imbalance is a causative or contributing factor.

The outcome in 83 patients with congenital clubfoot was evaluated at a mean age of 64 years using three validated questionnaires assessing both quality of life (short-form (SF)-36 and EQ-5D) and foot and ankle function (American Academy of Orthopaedic Surgeons (AAOS) Foot and Ankle questionnaire). In SF-36, male patients scored significantly better than male norms in seven of the eight domains, whereas female patients scored significantly worse than female norms in two of the eight. Male patients scored better than male norms in both the EQ-5D index (p = 0.027) and visual analogue scale (VAS) (p = 0.013), whereas female patients scored worse than female norms in the VAS (p < 0.001). Both male and female patients had a significantly worse outcome on the AAOS Core Scale than did norms. There was a significant correlation for both genders between the SF-36 Physical Component Summary Score and the AAOS Core Scale. The influence on activities of daily life was limited to foot and ankle problems in all patients, and in females there was an adverse effect in physical aspects of quality of life

Rocker bottom deformity may occur during the conservative treatment of idiopathic congenital clubfoot. Between 1975 and 1996, we treated 715 patients (1120 clubfeet) conservatively. A total of 23 patients (36 feet; 3.2%) developed a rocker bottom deformity. It is these patients that we have studied. The pathoanatomy of the rocker bottom deformity is characterised by a plantar convexity appearing between three and six months of age with the hindfoot equinus position remaining constant. The convexity initially involves the medial column, radiologically identified by the talo-first metatarsal angle and secondly by the lateral column, revealed radiologically as the calcaneo-fifth metatarsal angle. The apex of the deformity is usually at the midtrasal with a dorsal calcaneocuboid subluxation. Ideal management of clubfoot deformity should avoid this complication, with adequate manipulation and splinting and early Achilles’ percutaneous tenotomy if plantar convexity occurs. Adequate soft-tissue release provides satisfactory correction for rocker bottom deformity. However, this deformity requires more extensive and complex procedures than the standard surgical treatment of clubfoot. The need for lateral radiographs to ensure that the rocker bottom deformity is recognised early, is demonstrated

The Ponseti method of treating club foot has been shown to be effective in children up to two years of age. However, it is not known whether it is successful in older children. We retrospectively reviewed 17 children (24 feet) with congenital idiopathic club foot who presented after walking age and had undergone no previous treatment. All were treated by the method described by Ponseti, with minor modifications. The mean age at presentation was 3.9 years (1.2 to 9.0) and the mean follow-up was for 3.1 years (2.1 to 5.6). The mean time of immobilisation in a cast was 3.9 months (1.5 to 6.0). A painless plantigrade foot was obtained in 16 feet without the need for extensive soft-tissue release and/or bony procedures. Four patients (7 feet) had recurrent equinus which required a second tenotomy. Failure was observed in five patients (8 feet) who required a posterior release for full correction of the equinus deformity. We conclude that the Ponseti method is a safe, effective and low-cost treatment for neglected idiopathic club foot presenting after walking age

We report our initial experience of using the Ponseti method for the treatment of congenital idiopathic club foot. Between November 2002 and November 2004 we treated 100 feet in 66 children by this method. The standard protocol described by Ponseti was used except that, when necessary, percutaneous tenotomy of tendo Achillis were performed under general anaesthesia in the operating theatre and not under local anaesthesia in the out-patient department. The Pirani score was used for assessment and the mean follow-up time was 18 months (6 to 30). The results were also assessed in terms of the number of casts applied, the need for tenotomy of tendo Achillis and recurrence of the deformity. Tenotomy was required in 85 of the 100 feet. There was a failure to respond to the initial regimen in four feet which then required extensive soft-tissue release. Of the 96 feet which responded to initial casting, 31 (32%) had a recurrence, 16 of which were successfully treated by repeat casting and/or tenotomy and/or transfer of the tendon of tibialis anterior. The remaining 15 required extensive soft-tissue release. Poor compliance with the foot-abduction orthoses (Denis Browne splint) was thought to be the main cause of failure in these patients

The aetiology of congenital club foot is unclear. Although studies on populations, families and twins suggest a genetic component, the mode of inheritance does not comply with distinctive patterns. The Odense-based Danish Twin Registry contains data on all 73 000 twin pairs born in Denmark over the last 130 years. In 2002 all 46 418 twins born between 1931 and 1982 received a 17-page questionnaire, one question of which was ‘Were you born with club foot?’ A total of 94 twins answered ‘Yes’, giving an overall self-reported prevalence of congenital club foot of 0.0027 (95% confidence interval (CI) 0.0022 to 0.0034). We identified 55 complete twin pairs, representing 12 monozygotic, 22 dizygotic same sex (DZ. ss. ), 18 dizygotic other sex (DZ. os. ) and three unclassified. Two monozygotic and 2 DZ. ss. pairs were concordant. The pairwise concordance was 0.17 (95% CI 0.02 to 0.48) for monozygotic, 0.09 (95% CI 0.01 to 0.32) for DZ. ss. and 0.05 (95% CI 0.006 to 0.18) for all dizygotic (DZ. tot. ) twins. We have found evidence of a genetic component in congenital club foot, although non-genetic factors must play a predominant role

Continuous passive motion has been shown to be effective in the conservative treatment of idiopathic club foot. We wished to determine whether its use after operation could improve the results in resistant club feet which required an extensive soft-tissue release. There were 50 feet in the study. Posteromedial lateral release was performed in 39 feet but two were excluded due to early relapse. The mean age at surgery was eight months (5 to 12). Each foot was assigned a Dimeglio club foot score, which was used as a primary outcome measure, before operation and at 6, 12, 18 and 44 months after. Nineteen feet were randomly selected to receive continuous passive motion and 18 had standard immobilisation in a cast.

After surgery and subsequent immobilisation in a cast the Dimeglio club foot score improved from 10.3 before to 4.17 by 12 months and to 3.89 at 48 months. After operation followed by continuous passive motion the score improved from 9.68 before to 3.11 after 12 months, but deteriorated to 4.47 at 48 months. Analysis of variance adjusted for baseline values indicated a significantly better score in those having continuous passive motion up to one year after surgery, but after 18 and 48 months the outcomes were the same in both groups.

We performed CT to investigate how treatment may modify the basic skeletal pathology of congenital club foot. Two homogenous groups of patients treated by one of the authors (EI) or under his supervision were studied. The first included 32 patients with 47 club feet reviewed at a mean age of 25 years and treated by manipulation, application of toe-to-groin plaster casts and an extensive posteromedial release. The second included 32 patients with 49 club feet reviewed at a mean age of 19 years and treated by the Ponseti manipulation technique, application of toe-to-groin plaster casts and a limited posterior release. At follow-up the shape of the subtalar, talonavicular and calcaneocuboid joints was found to be altered in many feet in both groups. This did not appear to be influenced significantly by the type of treatment performed. Correction of the heel varus and the increased declination angle of the neck of the talus was better in the club feet of the second group, whereas reduction of the medial subluxation of the navicular was better in the first. There was a marked increase in the external ankle torsion angle in the first group and a moderate increase of this angle in the second group, in which medial subluxation of the cuboid on the anterior apophysis of the calcaneum was always corrected. Equinus was corrected in both groups but three-dimensional CT reconstruction of the whole foot showed that cavus, supination and adduction deformities were corrected much better in the second group

We studied in vivo the talonavicular alignment of club foot in infants using MRI. We examined 26 patients (36 feet) with congenital club foot. The mean age at examination was 9.0 months (4 to 12). All analyses used MRI of the earliest cartilaginous development of the tarsal bones in the transverse plane, rather than the ossific nucleus. The difference in the mean talar neck angle (44.0 ± 8.1°) in club foot was statistically significant (p < 0.001) when compared with that of the normal foot (30.8 ± 5.5°). The difference between the mean angles in the group treated by operation (47.9 ± 6.7°) and those treated conservatively (40.1 ± 7.5°) was also statistically significant. The anatomical relationship between the head of the talus and the navicular was divided into two patterns, based on the position of the mid-point of the navicular related to the long axis of the head. In the operative group, 18 feet were classified as having a medial shift of the navicular and none had a lateral shift. In the conservative group, 12 showed a medial shift of the navicular and six a lateral shift. All nine unaffected normal feet in which satisfactory MRI measurements were made showed a lateral shift of the navicular. Club feet had a larger talar neck angle and a more medially deviated navicular when compared with normal feet. This was more marked in the surgical group than in the conservative group

We operated on 111 patients with 159 congenital club feet with the aim of correcting the deformity and achieving dynamic muscle balance. Clinical and biomechanical assessment was undertaken at least six years after operation when the patient was more than 13 years of age. The mean follow-up was for 11 years 10 months (6 to 36 years).

Good and excellent results were obtained in 91.8%. Patients with normal function of the calf had a better outcome than those with weak calf muscles. The radiological changes were assessed in relation to the clinical outcome. The distribution of pressure under the foot was measured for biomechanical assessment.

Our results support the view that muscle imbalance is an aetiological factor in club foot. Early surgery seems to be preferable. It is suggested that operation should be undertaken as soon as possible after the age of six months, although it may be carried out up to the age of five years. The establishment of dynamic muscle balance appears to be an effective method of maintaining correction. Satisfactory long-term results can be achieved with adequate appearance and function.

We reviewed 19 children with 24 congenital club feet at a mean of 11 years after one-stage posteromedial release at the age of five years or older (mean 6.8 years). Thirteen feet had undergone previous surgery. Nineteen feet were functionally excellent or good, three were fair and two had required subtalar arthrodesis. Radiographs showed good alignment of the tarsal bones, although mild adduction or varus deformity remained in several feet. Deformities of the bones were more common in feet which had had previous surgery.

We treated 91 congenital club feet in 59 children using a modified Denis Browne splint, and followed them for an average of 6 years and 3 months. The modified splint has an aluminium crossbar holding a pair of plastic shoe inserts moulded into corrected positions, and its use was started in children whose ages ranged from four weeks to nine months. Operation was later required in only 31 feet in 20 children. We have reviewed the other 60 feet in 39 children treated by splintage alone. All 60 feet had excellent or good function and from radiographic assessment, equinus, adduction, varus and cavus deformities had all been well corrected. Our results show that the modified splint can give good results.

Forty-four feet in 28 children previously treated by a one-stage posteromedial release operation (the Turco procedure) were reviewed clinically and radiologically to determine the cause of residual adduction of the forefoot. In 21 clinically adducted feet (48%) the main cause of residual deformity was metatarsus varus alone or metatarsus varus in spite of talonavicular overcorrection; in five feet the cause was talonavicular subluxation. There was no residual adduction in 23 feet (52%) but only 12 had normal radiographic measurements. In the remaining feet, various forms of spurious correction of metatarsus varus and talonavicular subluxation or both were seen, resulting in normal-looking feet. Recession of the origin of abductor hallucis and release of the short plantar muscles and fascia at the time of posteromedial release is recommended. The forefoot adduction was satisfactorily corrected in 91% of the feet subsequently operated on using this modified procedure.

One hundred and twenty-nine unselected club feet were classified at birth into three grades of severity; 123 were followed up. The results of primary treatment were analysed and it is shown that the bad feet did worst. Serial splinting in plasters achieved lasting correction in nine in ten mild club feet, in half of the moderately deformed, but in only one in ten of the severely affected. Surgical correction succeeded in two out of three of the resistant feet, but had to be repeated in the others.

1. Seventy-three congenital club feet in fifty-one children have been reviewed between the ages of four and fourteen years to determine the incidence of residual adduction ofthe forefoot.

2. A radiological method of measuring metatarsus varus, based on the naviculo-metatarsal angle, is described.

3. On clinical examination 52 per cent of the feet had residual adduction of the forefoot, and metatarsus varus was present in 74 per cent of these.

4. There was no residual adduction in 48 per cent but only 45 per cent of these showed normal radiographic features. In the remainder various forms of spurious correction were seen.

5. For early treatment, detachment of the origin of the abductor hallucis muscle is recommended at the time of extended posterior release, with tenotomy of the tendon of insertion as an additional measure.