Functional dystonia: A pitfall for the foot and ankle surgeon.

Functional dystonia represents a condition where psychological distress is being expressed as involuntary muscle contractions. In the foot and ankle, it most commonly presents as a sudden onset of a painful fixed ankle/hindfoot deformity in a female patient with a history of trivial trauma or surgery. The "fixed deformity" found on clinical examination is usually correctable under general anesthesia. Less commonly, it can present in the toes or may present as paroxysmal muscle movements rather than a fixed deformity. CRPS may occur concurrently with the dystonia. Failure to consider the diagnosis leads to a long delay in appropriate diagnosis, patient distress and unnecessary or even harmful surgery. A better approach to this clinical syndrome is to define it as fixed abnormal posturing that is most commonly psychogenic. Early referral to a movement disorder clinic is recommended. The prognosis is generally poor as less than a quarter of patients report subjective long-term improvement even when managed in a movement disorder clinic. Foot and ankle surgeons should, whenever possible, avoid operating on patients with functional dystonia in order to avoid symptomatic deterioration.

A prospective study on surgical management of foot deformities in Charcot Marie tooth disease.

Foot deformities are frequently observed in patients with Charcot Marie tooth disease (CMT) and orthopaedic surgery is often required. Currently there is no evidence-based guideline on surgical management and only a few studies which have evaluated long-term outcomes of surgical procedures. The aim of the study was to evaluate longitudinally the effect of foot surgery in a cohort of CMT patients. Twenty-five CMT adult patients were assessed using a comprehensive group of validated scales and questionnaires before and after surgery. A wide range of surgical procedures was performed by one team of dedicated foot ankle orthopaedic surgeons. Foot alignment as measured by the foot posture index, pain, quality of life and callosities significantly improved after one year and the improvement was maintained up to 4 years after surgery. There was a trend towards a reduction in the number of falls post-operatively. Surgery had no effect on fatigue, balance and CMT examination score. Our findings showed significant improvement of pain, foot alignment, callosities and quality of life after surgery and suggested that foot deformity correction in adults with CMT performed in a specialised foot and ankle unit is beneficial.

Charcot neuroarthropathy in patients with Charcot Marie Tooth Disease.

Charcot Marie Tooth disease (CMT) is the most common inherited neuropathy and is also called Hereditary Motor Sensory Neuropathy (HMSN). Whilst both motor and sensory deficits are present, motor deficits tend to predominate over sensory deficits. Charcot neuroarthropathic joints occur in conditions, most commonly diabetes nowadays, where joints are destroyed in association with reduced protective sensation, pain in particular. Three cases of development of Charcot joint disorders in patients with CMT are discussed and the literature is reviewed. Orthopaedic surgeons should be aware that Charcot joints can occur in CMT and surgery can be complicated by Charcot joints.

Pes cavovarus in Charcot-Marie-Tooth compared to the idiopathic cavovarus foot: A preliminary weightbearing CT analysis.

BACKGROUND: Pes cavovarus is a foot deformity that can be idiopathic (I-PC) or acquired secondary to other pathology. Charcot-Marie-Tooth disease (CMT) is the most common adult cause for acquired pes cavovarus deformity (CMT-PC). The foot morphology of these distinct patient groups has not been previously investigated. The aim of this study was to assess if morphological differences exist between CMT-PC, I-PC and normal feet (controls) using weightbearing computed tomography (WBCT). METHODS: A retrospective analysis of WBCT scans performed between May 2013 and June 2017 was undertaken. WBCT scans from 17 CMT-PC, 17 I-PC and 17 healthy normally-aligned control feet (age-, side-, sex- and body mass index-matched) identified from a prospectively collected database, were analysed. Eight 2-dimensional (2D) and three 3-dimensional (3D) measurements were undertaken for each foot and mean values in the three groups were compared using one-way ANOVA with the Bonferroni correction. RESULTS: Significant differences were observed between CMT-PC or I-PC and controls (p<0.05). Two-dimensional measurements were similar in CMT-PC and I-PC, except for forefoot arch angle (p=0.04). 3D measurements (foot and ankle offset, calcaneal offset and hindfoot alignment angle) demonstrated that CMT-PC exhibited more severe hindfoot varus malalignment than I-PC (p=0.03, 0.04 and 0.02 respectively). CONCLUSIONS: CMT-related cavovarus and idiopathic cavovarus feet are morphologically different from healthy feet, and CMT feet exhibit increased forefoot supination and hindfoot malalignment compared to idiopathic forms. The use of novel three-dimensional analysis may help highlight subtle structural differences in patients with similar foot morphology but aetiologically different pathology. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Intraobserver and interobserver reliability of cone beam weightbearing semi-automatic three-dimensional measurements in symptomatic pes cavovarus.

INTRODUCTION: Pes cavovarus is a three-dimensional (3D) foot deformity. New 3D semi-automatic measurements utilising weightbearing computerised topography (WBCT) images have recently been proposed to assess hindfoot alignment, but reliability in pes cavovarus has never been investigated. The aim of this study was to assess intraobserver and interobserver reliability of the foot ankle offset (FAO), calcaneal offset (CO) and hindfoot alignment angle (HAA) in pes cavovarus. METHODS: Anonymised WBCT datasets from 51 feet (17 Charcot-Marie-Tooth related cavovarus, 17 idiopathic cavovarus and 17 controls) were retrospectively reviewed. Three observers (two senior foot and ankle fellows and one orthopaedic resident) independently measured FAO, CO and HAA using dedicated software, with measurements repeated two weeks apart. Subgroup analysis was performed to assess whether aetiology or severity of varus deformity and level of seniority affected reliability. RESULTS: Mean values for intra and interobserver reliability for FAO (r=0.98; ICC: 0.99), CO (r=0.97; ICC: 0.98) and HAA measurements (r=0.97; ICC: 0.98) were excellent. Subgroup analyses showed that FAO, CO and HAA's intra (r/ρ range, 0.77-0.95) and interobserver (ICC range, 0.88-0.98) reliability remained excellent in patients with Charcot-Marie-Tooth related cavovarus, idiopathic pes cavovarus and normal feet, regardless of the severity of deformity. No difference was found in FAO, CO and HAA mean values from three observers (p>0.05 in all cases). DISCUSSION: This study demonstrates that 3D semi-automatic measurements of WBCT images have excellent intra and interobserver reliability in the assessment of hindfoot alignment in pes cavovarus. Aetiology and severity of deformity, and level of seniority do not affect reliability of these measurements. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

The effects of weight bearing on the distal tibiofibular syndesmosis: A study comparing weight bearing-CT with conventional CT.

BACKGROUND: Syndesmotic injures are common and weight bearing imaging studies are often advocated to assess disruption. Although studies have examined the anatomical relationship between the fibula and incisura, the effect of weight-bearing on the syndesmosis has not been well reported. We characterise the changes which occur at the syndesmosis during weight-bearing. METHODS: In this retrospective review we analysed the position of the fibula at the syndesmosis in a cohort of patients who underwent both non-weight-bearing and weight-bearing CT scans. The relative position of the fibula to the incisura was analysed to determine translation and rotation in the axial plane. RESULTS: 26 patients were included. Comparison of measurements revealed statistically significant differences between groups which indicated that on weight-bearing the fibula translated laterally and posteriorly, and rotated externally with respect to the incisura. CONCLUSIONS: This is the first study to measure the differences in position of the syndesmosis during weight-bearing in a population of patients that have undergone both weight bearing and non weight bearing CT. Our study confirms that weight-bearing results in lateral and posterior translation, and external rotation of the fibula in relation to the incisura and our findings should help in future studies looking at the effect of weight bearing on syndesmotic pathology.

Gastrocnemius tightness: A population based observational study.

BACKGROUND: Gastrocnemius tightness is believed to be associated with multiple musculoskeletal pathologies such as back pain, plantar fasciitis and metatarsalgia. Although surgical treatment of gastrocnemius tightness is gaining popularity the objective definition of a gastrocnemius contracture has not been determined. The aim of our study was therefore to quantify gastrocnemius tightness in a normal population. METHODS: Adult participants with no obvious foot and ankle pathology were recruited. Gastrocnemius tightness was quantified using a weightbearing lunge test. Maximal ankle-foot dorsiflexion was measured on participants with the knee in full extension and flexed to 20° using a digital inclinometer. The ankle-foot dorsiflexion index or ADI (difference in ankle dorsiflexion with the knee extended and flexed) was calculated. The ADI values were plotted on a histogram to identify the distribution of values and were compared according to participant demographics. RESULTS: 800 limbs from 400 participants were examined. There was a wide distribution of absolute values of maximal ankle-foot dorsiflexion ranging from 8 to 52°. The ADI ranged from 0 to19° and approximated to a normal distribution. The mean ADI was 6.04±3.49° and was positively correlated with age (r=0.132, P<0.001) and negatively correlated with physical activity (r=-0.88, P=0.015). CONCLUSION(S): Our study is the first to quantify gastrocnemius tightness in a large healthy adult population with differences observed by age and physical activity. We have defined an easy and reproducible weightbearing test that can be used in both research and clinical settings. The majority of the population have some degree of gastrocnemius tightness and values of ADI greater than 13° (>2 SD of the mean), as measured by the lunge test, may be considered abnormal.

Prevalence and orthopedic management of foot and ankle deformities in Charcot-Marie-Tooth disease.

INTRODUCTION: Foot deformities are frequent complications in Charcot-Marie-Tooth disease (CMT) patients, often requiring orthopedic surgery. However, there are no prospective, randomized studies on surgical management, and there is variation in the approaches among centers both within and between countries. METHODS: In this study we assessed the frequency of foot deformities and surgery among patients recruited into the Inherited Neuropathies Consortium (INC). We also designed a survey addressed to orthopedic surgeons at INC centers to determine whether surgical approaches to orthopedic complications in CMT are variable. RESULTS: Foot deformities were reported in 71% of CMT patients; 30% of the patients had surgery. Survey questions were answered by 16 surgeons working in different specialized centers. Most of the respondents were foot and ankle surgeons. There was marked variation in surgical management. DISCUSSION: Our findings confirm that the approaches to orthopedic management of CMT are varied. We identify areas that require further research. Muscle Nerve 57: 255-259, 2018.

Treatment of first metatarsophalangeal joint arthritis using hemiarthroplasty with a synthetic cartilage implant or arthrodesis: A comparison of operative and recovery time.

BACKGROUND: First metatarsophalangeal joint (MTPJ1) hemiarthroplasty using a novel synthetic cartilage implant was as effective and safe as MTPJ1 arthrodesis in a randomized clinical trial. We retrospectively evaluated operative time and recovery period for implant hemiarthroplasty (n=152) and MTPJ1 arthrodesis (n=50). METHODS: Perioperative data were assessed for operative and anaesthesia times. Recovery and return to function were prospectively assessed with the Foot and Ankle Ability Measure (FAAM) Sports and Activities of Daily Living (ADL) subscales and SF-36 Physical Functioning (PF) subscore. RESULTS: Mean operative time for hemiarthroplasty was 35±12.3min and 58±21.5min for arthrodesis (p<0.001). Anaesthesia duration was 28min shorter with hemiarthroplasty (p<0.001). At weeks 2 and 6 postoperative, hemiarthroplasty patients demonstrated clinically and statistically significantly higher FAAM Sport, FAAM ADL, and SF-36 PF subscores versus arthrodesis patients. CONCLUSION: MTPJ1 hemiarthroplasty with a synthetic cartilage implant took less operative time and resulted in faster recovery than arthrodesis. LEVEL OF EVIDENCE: III, Retrospective case control study.

Acute Achilles tendon rupture.

This is one of a series of occasional articles highlighting conditions that may be more common than many doctors realise or may be missed at first presentation. The series advisers are Anthony Harnden, professor of primary care, Department of Primary Care Health Sciences, University of Oxford, and Richard Lehman, general practitioner, Banbury. To suggest a topic for this series, please email us at practice@bmj.com.

Toenail paronychia.

Paronychia is an inflammation of the tissues alongside the nail. It may be acute or chronic and can be seen in isolation or in association with an ingrowing toenail. Acute paronychial infections develop when a disruption occurs between the seal of the nail fold and the nail plate, providing a portal of entry for invading organisms. The treatment of paronychia associated with an ingrowing toenail is aimed at treating the causal toenail. In paronychia not associated with an ingrowing toenail, antibiotics may cure an early infection but surgical drainage of an abscess is often required. In this case, an intra-sulcal approach is preferable to a nail fold incision. Chronic paronychia is less common in the feet than in the hands. It is a form of contact dermatitis and is frequently non-infective, however the chronically irritated tissue may become secondarily colonised by fungi. A dermatology consultation should be obtained for suspected chronic paronychia. Patients with chronic paronychia that is unresponsive to standard treatment should be investigated for unusual causes, such as malignancy. An algorithm for the treatment of paronychia is presented in this review.

Comparison of dorsal and dorsomedial displacement in evaluation of first ray hypermobility in feet with and without hallux valgus.

BACKGROUND: Hypermobility of the first ray, a probable primary cause of hallux valgus, has traditionally been evaluated in the dorsal direction only although the first tarso-metatarsal joint allows movement in a dorso-medial direction. MATERIALS AND METHODS: 600 feet, divided according to the presence or absence of hallux valgus, were evaluated for both dorsal and dorso-medial displacement using a Klaue device. RESULTS: In the control group, the mean first ray displacement was 7.2mm (4.2-11.3) in the dorsal direction (sagittal plane) and 8.3mm (4.0-12.6) in the 45° dorso-medial direction. In the hallux valgus group, the mean first ray mobility was 9.8mm (5.2-14.1) in the dorsal direction compared to a mean of 11.0mm (5.9-16.2) in the 45° dorso-medial direction. CONCLUSION: It is a paradox that hypermobility of the first ray is measured in only a dorsal (vertical) direction whereas a hallux valgus angle and an intermetatarsal angle are only measured in a transverse plane. Furthermore, the weightbearing foot pronates during gait and the first metatarsal is displaced in a dorsomedial direction rather than a pure dorsal direction. It is suggested that measurement hypermobility of the first ray at a 45° dorso-medial direction is more appropriate.

Technical tip: Dorsal transmetatarsal approach to intermetatarsal and deep plantar lesions.

UNLABELLED: Synovial and chondromatous lesions can extend dorsally, intermetatarsally and deep into the vault of the longitudinal and transverse plantar arches of the foot. The lesions may prove difficult to excise even with combined approaches. Two cases where a transmetatarsal approach by excision of the base of the third metatarsal enabled successful complete excision of the lesions are presented. LEVEL OF EVIDENCE: Level V, expert opinion.

Patient satisfaction and function after bilateral ankle arthrodeses.

BACKGROUND: The optimum way to manage patients with bilateral ankle arthritis (AA) is unclear. METHODS: This review was performed to report the midterm satisfaction and functional outcome of a series of patients who have undergone bilateral staged ankle arthrodesis. RESULTS: Eight patients, median age 68.5 yrs (range 59-80) were followed-up for a median of 58.5 months (range 24-100). All fusions united in a median time of 12.8 weeks (range 10-19) Their median AOFAS hindfoot score was 79.5 (range 71-90). Six patients (75%) were very satisfied, one was satisfied, and the other neither satisfied nor dissatisfied. Two patients developed symptomatic subtalar arthritis requiring subtalar fusion. CONCLUSIONS: This is the first study to report the outcome of bilateral AA independent to that of unilateral AA. Bilateral AA appears to give patients a good functional result with high patient reported satisfaction into the medium term.

Complete spontaneous avascular necrosis of the adult navicula associated with Mee's growth arrest lines of the great and second toenails.

Spontaneous total avascular necrosis of the tarsal navicula has been well documented in children (Kohler's disease) but is uncommon in adults where partial necrosis is usually seen after trauma or in Müller-Weiss disease. A case of spontaneous complete navicular osteonecrosis in a 46 year old female is described; she had accompanying Mee's leuchonychial lines in the toenails of the great and second toes only; the lines resolved after 9 months. She has been treated with an excision of the navicula and interpositional iliac crest bone graft talo-cuneiform fusion with resolution of her pain. It is postulated that the combination of the Mee's lines and avascular necrosis of the navicula indicates an occlusion of the dorsalis pedis in a predisposed individual.

Oedema of the abductor digiti quinti muscle due to subacute denervation: report of two cases.

The clinical presentation of abductor digiti quinti (ADQ) denervation is often non-specific. The diagnosis is generally clinical and may be easily missed. This case report of two patients describes the magnetic resonance imaging (MRI) finding of unilateral oedema and fatty infiltration isolated to the ADQ. A 36-year old woman who presented with laterally located left foot pain was initially diagnosed as having plantar fasciitis. An MRI scan arranged due to the unusual site of the pain showed increased signal intensity within the ADQ muscle on T1 and T2 images indicating fatty infiltration. Short tau inversion recovery (STIR) images showed hyperintensity of the ADQ indicating oedema. The MRI scan of a 45-year old man who presented with a three month history of left heel pain revealed similar findings. These MRI appearances indicate subacute denervation, which, when involving solely the ADQ muscle suggests entrapment of the first branch of the lateral plantar nerve. Consideration of this imaging finding when examining MRI scans of patients with non-specific heel pain has the potential to facilitate diagnosis.

Open ankle arthrodeses via an anterior approach.

BACKGROUND: In open ankle arthrodesis, debate remains as to which surgical approach and fixation devices should be used. The purpose of this study was to identify union, complication, and patient satisfaction rates of ankle fusions performed at our institution, using the plane between extensor hallucis longus and tibialis anterior with medial tibiotalar screw internal fixation. MATERIALS AND METHODS: A retrospective review was performed of all isolated primary fusions between 2005 and 2009. Eighty-two ankles were identified in 73 patients. All patient records were reviewed, and 57 patients (65 ankles) attended for clinical evaluation and scoring. Age range at surgery was 18 to 75 years (mean, 56.1 years); 8 patients were smokers. Diagnoses were trauma in 52 patients (63%), osteoarthritis in 17, rheumatoid arthritis in 7, Charcot-Marie-Tooth disease in 3, congenital talipes equinovarus in 2, and talar avascular necrosis in 1. Follow-up range was 7 months to 8.3 years (mean, 4 years). RESULTS: Time to union ranged from 8 to 39 weeks (mean, 13.3) with a union rate of 100%. The AOFAS range was 12 to 93 (mean, 70). Eighty percent were "very satisfied" or "satisfied." Major complication rate was 14.6%: 7 malalignments; 3 wound problems; 2 complex regional pain syndrome; and 2 delayed unions, both smokers. CONCLUSIONS: An excellent union rate, high patient satisfaction, and low complication rate were achieved with this technique. Varus malalignment and persistent pain resulted in dissatisfaction. Many patients remained highly active, and bilaterally fused patients functioned as well as unilateral ones. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Comparison of three different fixation methods of calcaneal osteotomies.

BACKGROUND: There are various methods available to fix a calcaneal osteotomy, ranging from screws to plates and staples. It is not clear if one method is superior to the other. In this series we compare the complications and union rates of 3 different methods of fixation. METHODS: A retrospective review of the records of a consecutive series of patients who had a calcaneal osteotomy was undertaken. All patients had their osteotomy by the same technique, however the subsequent fixation was performed using 3 different methods: a lateral locking plate, a headless, or a headed screw. The screws were placed through a separate stab incision inserted from the infero-posterior heel. Records were kept of subsequent symptoms from the hardware and need for hardware removal as well as any complications. When screws were inserted, the entry point in relation to the weight-bearing surface of the calcaneus was also recorded. Sixty-seven osteotomies were investigated, of which 17 were fixed using a headed screw, 18 using a headless screw, and the remaining 32 were fixed using a lateral plate. RESULTS: There was an overall 97% union rate. The only 2 cases of delayed union were both fixed using a lateral plate. Overall, 47% of the headed screws, 11% of the headless screws, and 6% of the lateral plates were removed to address symptoms that were suspected to arise from the hardware. There was a 10% rate of wound complication in the lateral plate cohort. There were no cases of sural nerve injury or neuroma. No correlation was found between entry position of screw and subsequent hardware symptoms. CONCLUSIONS: Calcaneal osteotomies have high union rates regardless of fixation method. Fixation using a headed screw is associated with a high rate of secondary screw removal. This was unrelated to the position of the screw in relation to the weight-bearing surface of the calcaneus in our series. Hardware problems were less frequent in the headless screw or the lateral plate groups; however, the incidence of local wound complications and radiological delayed union was higher in the group fixed with a lateral plate. This may be related to the greater soft tissue dissection and lesser compression achieved at the osteotomy site. LEVEL OF EVIDENCE: Level III, retrospective case control study.

Nils Silfverskiöld (1888-1957) and gastrocnemius contracture.

Nils Silfverskiöld was an orthopaedic surgeon, Swedish aristocrat, bon vivant, Olympic gymnast, left wing intellectual and anti-Nazi who described that the force required to dorsiflex the ankle in spastic equinus contracture decreased with knee flexion in isolated gastrocnemius contracture. He advocated detaching the origins of the gastrocnemii from the femur and reattaching them to the tibia. The Silfverskiöld knee flexion test has now also been adapted to distinguish between isolated gastrocnemius contracture and combined shortening of the gastrocnemius-soleus complex in non-spastic contracture by measuring the range of ankle dorsiflexion with the knee flexed and the knee straight.

SPECT-CT imaging of obscure foot and ankle pain.

Obscure pain around the foot and ankle can be notoriously difficult to localise. Anatomical imaging studies will often require supporting evidence from functional scintigraphic studies in the more difficult cases. Single photon emission computerised tomography-computed tomography (SPECT-CT) is a novel technique combining these two studies instantaneously in a single scan. We present six cases from our ongoing experience with SPECT-CT. Caution in the use of SPEC-CT is suggested by one of these cases. Five cases extol the virtues we perceive of the technique whilst the sixth presents a note of caution. Our findings are supported in the current literature and serve to refine the place for this emerging imaging technique.