Adult-acquired flatfoot deformity following posterior tibialis to dorsum transfer: a case report

A previous study showed that flatfoot deformity does not develop after posterior tibialis to dorsum transfer in patients with peroneal nerve palsy. Their conclusion was that it is the unopposed pull of the peroneus brevis which leads to the flatfoot deformity in posterior tibial tendon dysfunction. This case report presents a patient who developed a flatfoot deformity after posterior tibialis to dorsum transfer despite nonfunctioning peroneal muscles.     

Tibialis posterior tendon dysfunction: a primary or secondary problem?

Seventeen patients with a mean follow-up of 64.4 months following a tibialis posterior tendon transfer to regain active foot dorsiflexion were clinically examined specifically for signs of tibialis posterior tendon dysfunction. The results show that 8 patients (47%) had Grade 4 or better power of eversion but none had a clinical flatfoot on the Harris-Beath footprints. Only 6% had forefoot abduction; 17% exhibited hindfoot valgus and 82% were able to perform the single-heel rise. Tibialis posterior tendon dysfunction therefore does not appear to be an inevitable sequel of tibialis posterior tendon transfer even in the presence of a functioning peroneal muscle. Other studies have noted that a pre-existent flatfoot was often present in patients with tibialis posterior tendon dysfunction. None of the patients in this study had pre-existent flatfoot. We suggest that a predisposition, in the form of a pre-existent tendency to flatfoot may also be a factor in the pathogenesis of tibialis posterior tendon dysfunction. This may explain the long-term failure of flexor digitorum longus and flexor hallucis longus tendon transfers in the treatment for tibialis posterior tendon dysfunction when the biomechanics of the foot has not been altered.     

Rückfu?valgus

The clinical finding of flatfoot is characterized by a flattening of the medial longitudinal arch and valgus deformity of the hindfoot. The differential diagnosis of flatfoot is the physiological, flexible, contracted flatfoot, which occurs as a congenital or acquired deformity. Congenital flatfoot deformity requires early intensive therapy, while a flexible flatfoot in children has a good prognosis and conservative treatment usually leads to a stable and sufficient load-bearing foot. Severe flatfoot in children can be corrected successfully by simple, minimally invasive procedures. In adults with symptomatic flatfoot, which usually occurs due to an insufficiency of the tendon of the tibialis posterior, conservative therapy with insoles, shoe modifications and physiotherapeutic measures can lead to significant improvement, otherwise surgical correction is recommended. Early, stage-appropriate therapy helps to prevent an impending decompensation of the hindfoot.     

Hindfoot valgus. Diagnosis and therapy of flatfoot

The clinical finding of flatfoot is characterized by a flattening of the medial longitudinal arch and valgus deformity of the hindfoot. The differential diagnosis of flatfoot is the physiological, flexible, contracted flatfoot, which occurs as a congenital or acquired deformity. Congenital flatfoot deformity requires early intensive therapy, while a flexible flatfoot in children has a good prognosis and conservative treatment usually leads to a stable and sufficient load-bearing foot. Severe flatfoot in children can be corrected successfully by simple, minimally invasive procedures. In adults with symptomatic flatfoot, which usually occurs due to an insufficiency of the tendon of the tibialis posterior, conservative therapy with insoles, shoe modifications and physiotherapeutic measures can lead to significant improvement, otherwise surgical correction is recommended. Early, stage-appropriate therapy helps to prevent an impending decompensation of the hindfoot.     

Medial flexor digitorum longus tendon augmentation and lateral foot column lengthening or reorienting triple arthrodesis as surgical therapy of posterior tibial tendon dysfunction

QUESTION: The purpose of this study was to evaluate the alignment and functional outcome after surgical augmentation of the tibialis posterior by tendon transfer and lateral column lengthening by osteotomy of the os calcis, calcaneo-cuboidal arthrodesis or reorientating triple arthrodesis. METHODS: From 1991 to 1999 41 patients with the clinical and radiological diagnosis of dysfunction of the tibialis posterior tendon underwent surgical exploration and repair. These 41 patients (22 women, 19 men) had an average age of 44.3 years (range, 19-69 years) and had been symptomatic for an average of 2.3 years (range, 6 months to 6 years). All patients had the symptoms of a painful flatfoot deformity without dynamic support along the medioplantar aspect. Flexor digitorum longus (FDL) tendon transfer as reconstruction of the tibialis posterior tendon was performed in the cases without major deformity (n = 77). Patients underwent FDL transfer and lengthening osteotomy (n = 15) of the os calcis or calcaneocuboidal (c-c) arthrodesis (n = 12) if passive correction of the foot deformity was still possible and reorientating triple arthrodesis (n = 7) when a fixed flatfoot deformity had developed. AOFAS score and radiological examination were used preoperatively and in the follow-up. RESULTS: The AOFAS score improved for stage 1 patients after a mean follow-up of 43 months with FDL transfer from a preoperative mean of 54 to 84 points, for stage II patients with FDL transfer and lengthening osteotomy (mean follow-up 36 m) from 47 to 92 points, with c-c arthrodesis (follow-up 66 m) from 48 to 86 points, and for stage III patients with triple arthrodesis from 42 to 72 points. In two patients, the deformity failed to improve (stage I) necessitating a revision surgery with a calceneo-cuboidal lengthening arthrodesis for relapsing deformity. CONCLUSION: In order to correct deformity and provide substantial relief of foot pain and dysfunction, we recommend the transfer of the FDL tendon in flexible flat foot deformity together with lengthening osteotomy. This treatment will provide optimal restoration of a dynamic support along the medioplantar aspect of the foot and is functionally superior to a c-c arthrodesis. Reorientating triple arthrodesis showed fair functional results and is recommended--for fixed flatfoot deformity.     

Isolated talonavicular arthrodesis in patients with rheumatoid arthritis of the foot and tibialis posterior tendon dysfunction

Background  

The foot is often affected in patients with rheumatoid arthritis. Subtalar joints are involved more frequently than ankle joints. Deformities of subtalar joints often lead to painful flatfoot and valgus deformity of the heel. Major contributors to the early development of foot deformities include talonavicular joint destruction and tibialis posterior tendon dysfunction, mainly due to its rupture.     

Nonoperative treatment of posterior tibial tendon dysfunction

One of the most common causes of acquired flatfoot deformity in adults is dysfunction of the posterior tibial tendon. The main function of the posterior tibial tendon is to invert the midfoot and lock the transverse tarsal joints (talonavicular and calcaneocuboid joints). When the tendon fails to function properly, a progressive flatfoot deformity develops. Because the disease process is a continuum, a staging system has been devised to offer guidelines for nonoperative and operative treatment of this problem. The rationale for nonoperative treatment of this disorder is to support the longitudinal arch and to decrease the valgus angulation of the calcaneus for flexible flatfoot deformity, and to immobilize and support the hindfoot and midfoot for rigid flatfoot deformities. The success of nonoperative treatment first requires the assessment of the flexibility of the flatfoot deformity. For a flexible deformity, the custom orthosis should be fitted with the foot and ankle in a corrected position as close to the neutral position as possible. Whereas, for a rigid deformity, it is imperative for the custom orthosis to be fitted with the affected foot and ankle in an in situ position.     

Tibialis posterior dysfunction as a cause of flatfeet in elderly patients

Background: Tibialis posterior is a frequent cause of an acquired flatfoot deformity and the prevalence is not known. If tibialis posterior dysfunction was found to occur frequently, a greater awareness may result leading to earlier patient diagnosis, referral and treatment.Objectives: To validate a screening questionnaire for tibialis posterior dysfunction, and to investigate the prevalence of tibialis posterior dysfunction in a high-risk patient population.Methods: The screening questionnaire was given prospectively to 65 patients (44 females, 21 males; mean age 79.6 years) attending an unrelated care of the elderly appointment. A foot and ankle surgery fellow separately examined all feet for tibialis posterior dysfunction.Results: The survey was 100% sensitive and 98.3 % specific at detecting tibialis posterior dysfunction. Six of the 65 patients (5 females, 1 male) had tibialis posterior dysfunction, and two had bilateral involvement. All six of the patients had longstanding symptoms, all had consulted their doctor and three had seen an orthopaedic surgeon; only one of the six patients had been correctly diagnosed.Conclusions: This study suggests that tibialis posterior dysfunction occurs frequently, but is seldom diagnosed in elderly women. Further epidemiologic studies are needed to determine the true prevalence.     

Long-term results of tibialis posterior tendon transfer for drop-foot

Twelve patients with drop-foot secondary to sciatic or common peroneal nerve palsy treated with transfer of the tibialis posterior tendon were followed-up for a mean of 90 (24-300) months. In 10 patients the results were 'excellent' or 'good'. In 11 patients grade 4 or 5 power of dorsiflexion was achieved, although the torque, as measured with a Cybex II dynamometer, and generated by the transferred tendon, was only about 30% of the normal side. Seven patients were able to dorsiflex their foot to the neutral position and beyond. The results appeared to be better in men under 30 years of age with common peroneal palsies. A painful flatfoot acquired in adulthood does not appear to be a significant long-term complication despite the loss of a functioning tibialis posterior tendon.     

Calcaneocuboid distraction arthrodesis for posterior tibial tendon dysfunction and flatfoot: a cadaveric study

Nine fresh-frozen foot specimens were studied to determine the mechanical behavior of the foot using calcaneocuboid distraction arthrodesis, an operation designed for treatment of posterior tibial tendon dysfunction with flatfoot deformity. Flatfoot deformity was created in cadaveric specimens, and to simulate toe-off phase of gait, loads were applied to the plantar surface of the foot and six tendons. Three-dimensional tarsal bone positions were determined with a magnetic tracking system. With ligament sectioning, flatfoot deformity was observed and average arch height decreased 53 +/- 3.5 mm. Height arch increased after calcaneocuboid distraction arthrodesis an average of 3.2 +/- 3.6 mm and was less than normal arch at an average of 2.1 +/- 2.4 mm. Metatarsotalar alignment compared with flatfoot improved after calcaneocuboid distraction arthrodesis in adduction and inversion to the extent that these were not significantly different from intact foot positions. Calcaneotalar position improved after calcaneocuboid distraction arthrodesis in adduction and inversion. Calcaneocuboid alignment compared with flatfoot improved after calcaneocuboid distraction arthrodesis in adduction, plantar flexion, and eversion, but compared with an intact foot was overcorrected in all three planes of motion. Arch alignment in simulated toe-off phase of gait in cadaveric feet was improved significantly with calcaneocuboid distraction arthrodesis but was not reduced anatomically.     

Injury of the tibialis posterior tendon: a cause of acquired valgus foot in childhood

Accidental division of the tibialis posterior tendon near the medial malleolus is easily overlooked and can, if left untreated, cause a painful planovalgus deformity of the foot. Two such patients are described, who had small wounds near the medial malleolus and in whom the tendon's damage was not initially diagnosed. Both patients came later with a painful valgus flat foot. Diagnosis of the lesion may be difficult because the inversion and supination action of the tibialis posterior tendon can be mimicked by the long flexor tendons of the toes. A patient with an intact tibialis posterior tendon can invert and supinate the foot and then plantarflex and dorsiflex the toes with the foot held in that position. Damage to the tendon should be suspected in all penetrating wounds near the medial malleolus.     

The contributions of anterior and posterior tibialis dysfunction to varus foot deformity in patients with cerebral palsy

BACKGROUND: According to traditional teaching, the posterior tibialis is the main cause of varus foot deformity in patients with cerebral palsy. However, the relative frequency of anterior and posterior tibialis dysfunction has only been reported with use of dynamic electromyography in relatively small series of patients, with contrasting results. The purpose of the current study was to determine the relative prevalence of posterior and anterior tibialis dysfunction with use of gait analysis in a large group of patients with cerebral palsy and varus foot deformity. METHODS: The muscular contributors to varus foot deformity in seventy-eight patients (eighty-eight feet) who had cerebral palsy were evaluated with use of computerized motion analysis and dynamic electromyography. Data also were examined to identify any relationships between the timing of varus during gait and the contributing muscle. RESULTS: The muscular contributor to varus deformity was the anterior tibialis in thirty feet, the posterior tibialis in twenty-nine feet, both the anterior tibialis and the posterior tibialis in twenty-seven feet, and another contributor in two feet. Seventy feet had varus deformity during both stance phase and swing phase. Of these seventy feet, twenty-five exhibited dysfunction of the anterior tibialis, twenty exhibited dysfunction of the posterior tibialis, and twenty-three exhibited dysfunction of both muscles. Therefore, the timing of varus was not predictive of the contributing muscle or muscles. CONCLUSIONS: The current study demonstrated a higher prevalence of anterior tibialis dysfunction, both alone and in combination with posterior tibialis dysfunction, as a contributor to pes varus in patients with pes varus and cerebral palsy than had been reported previously. Dynamic electromyography provides clinically useful information for the assessment of such patients.     

Calcaneocuboid joint pressure after lateral column lengthening in a cadaveric planovalgus deformity model

The purpose of this study is twofold: first, to measure the joint contact pressure across the calcaneocuboid joint in a planovalgus deformity and compare the results to pressures measured in a normal foot; and second, to determine the change in pressure across the calcaneocuboid joint after an Evan's-type calcaneal lengthening osteotomy. The effect of this procedure on the calcaneocuboid joint was evaluated using seven cadaver feet to measure peak pressure across the calcaneocuboid joint under a constant load. Each foot was sectioned medially to reproduce a deformity consistent with an adult, acquired flatfoot. Each flatfoot deformity was then corrected using a ten-millimeter lateral column lengthening osteotomy. Joint pressures were measured in the normal foot, the created flatfoot and then in the corrected flatfoot. Peak pressures across the joint increased significantly from baseline in the flatfoot (p <0.05). However, the change in pressure from the flatfoot to the corrected foot was not significant, and in some cases peak pressures in the corrected foot were actually lower than in the flatfoot. These findings indicate that calcaneal lengthening through an Evan's osteotomy does not increase pressure across the calcaneocuboid joint beyond physiologic loads in the flatfoot.     

The flexible flatfoot in the adult

The adult acquired flatfoot deformity is characterized by flattening of the medial longitudinal arch with insufficiency of the supporting posteromedial soft tissue structures of the ankle and hindfoot. While the etiology of this deformity can be arthritic or traumatic in nature, it is most commonly associated with posterior tibial tendon dysfunction (PTTD). By one estimate, PTTD affects approximately five million people in the United States. The clinical presentation of adult flatfoot can range from a flexible deformity with normal joint integrity to a rigid, arthritic foot.     

Calcaneocuboid distraction arthrodesis and first metatarsocuneiform arthrodesis for correction of acquired flatfoot deformity in a cadaver model

BACKGROUND: Lateral column lengthening has been associated with residual forefoot supination and symptomatic lateral overload in treatment of acquired flatfoot. A medial column procedure may be useful to redistribute load to the medial column. We evaluated radiographic and pressure changes in a severe flatfoot model with lateral column lengthening and investigated the effect of an added first metatarsocuneiform arthrodesis. METHODS: Ten cadaver specimens were loaded in simulated double-legged stance, and radiographic and pressure data were collected for all tested states. Calcaneocuboid arthrodesis was done with a 10-mm foam wedge. Residual forefoot varus was corrected through the first metatarsocuneiform joint. RESULTS: Differences in the mean lateral talar-first metatarsal angle, talonavicular angle, talocalcaneal angle, and calcaneal pitch were significant between the intact foot and the flatfoot. After calcaneocuboid distraction arthrodesis and tendon transfer, the lateral talar-first metatarsal angle, talonavicular angle, and calcaneal pitch were significantly different from the flatfoot. After added first metatarsocuneiform arthrodesis, the talonavicular angle was not significantly different from the intact foot. Lateral forefoot pressure increased in the flatfoot after lateral column lengthening but was not significantly different from the intact foot after first metarsocuneiform arthrodesis was added. CONCLUSIONS: Adding first metatarsocuneiform arthrodesis to calcaneocuboid distraction arthrodesis for treatment of flatfoot deformity provided improvement in radiographic and pedobarographic parameters of a severe model of stage II posterior tibial tendon dysfunction.     

Posterior tibial tendon dysfunction. Diagnosis, evaluation, and treatment

Posterior tibial tendon dysfunction (PTTD) is a complex multifaceted condition that can affect the lower extremity. Rarely mentioned 20 years ago, today it is the subject of numerous articles, books, and is a topic at most scientific seminars relating to the foot and ankle. It is a muscle imbalance initiated by a rupture, avulsion, or chronic inflammation of the tibialis posterior tendon. With time, it progresses from a flexible to rigid flatfoot deformity. Left untreated, peritalar dislocation and degenerative joint disease may develop. This article discusses the diagnosis, evaluation, and treatment of PTTD.     

Pathophysiology of Charcot-Marie-Tooth disease

The etiology of the foot deformity in patients with Charcot-Marie-Tooth disease has not previously been discussed in relation to the extrinsic muscle function around the foot and ankle. Eight adult patients with a strong familial history were evaluated, and their foot findings were remarkably similar. All demonstrated a marked cavus deformity that was secondary to a forefoot equinus associated with contracture of the plantar fascia and a varus deformity of the calcaneus. The muscle function demonstrated marked weakness of the tibialis anterior and peroneus brevis muscles, whereas the peroneus longus and posterior calf muscles were rated as good to normal. Based on the relative strengths of these muscles and the progression of weakness, the authors hypothesize that the deformity observed in patients with Charcot-Marie-Tooth disease is secondary to the weakness of the tibialis anterior, peroneus brevis, and the intrinsic muscles, with their natural antagonists, the peroneus longus and the tibialis posterior muscles causing most of the deformity noted in these adult patients.     

An anomalous hindfoot insertion of the posterior tibialis tendon

The posterior tibialis tendon has numerous insertions but none into the hindfoot has ever been reported in the literature. We present the operative and histological findings of an anomalous insertion slip into the sustentaculum tali in an adult patient with flatfoot deformity.     

Electromyographic analysis of the leg muscles in the hemiplegic patients with equinovarus deformity of the foot

A series of EMG study of the leg muscles was carried out with a wire electrode in 86 hemiplegic patients of stroke to visualize the role of each muscle either in the development of equinovarus deformity of the foot or in correcting the deformity through tendon transfer. The muscles examined were anterior tibialis, posterior tibialis, gastrocnemius, soleus, flexor digitorum longus and peroneus brevis of the affected side. Tonic discharge of those muscles was recorded as the patients were elevating the affected leg in supine, sitting or standing posture or were standing on legs. On lifting up the affected limb, most patients showed electrical activity of anterior tibialis with or without simultaneous activity of other muscles, most frequently with that of flexor digitorum longus or gastrocnemius. When the patient stood on legs electromyographic discharge appeared most frequently in soleus. Varus deformity of the foot significantly correlated to the lack of the electrical activity of peroneus brevis. Both such abnormal activity of anterior tibialis and the lack of activity of peroneus seemed to be the main causes for the varus deformity. Postoperative EMG study in the patients who underwent Watkins-Barr procedure of anterior transfer of the posterior tibialis tendon, showed that the posterior tibialis was rather inactive both in elevating the leg and in standing on legs. Varus deformity was corrected independent of the discharge of posterior tibialis. The author concluded that the correction of the varus deformity after Watkins-Barr procedure was mainly obtained from the tenodesis effect. The tenodesis provides the checkline effect on the equinus and varus deformity, which reinforces the dorsiflexing action of anterior tibialis and attenuates its inverting action of the same muscle.     

The role of medial ligaments and tibialis posterior in stabilising the medial longitudinal foot arch: a cadaveric gait simulator study

BackgroundDebate exists whether adult acquired flatfoot deformity develops secondary to tibialis posterior (TibPost) tendon insufficiency, failure of the ligamentous structures, or a combination of both.AimThe aim of this study is to determine the contribution of the different medial ligaments in the development of acquired flatfoot pathology. Also to standardise cadaveric flatfoot models for biomechanical research and orthopaedic training.MethodsFive cadaveric feet were tested on a dynamic gait simulator. Following tests on the intact foot, the medial ligaments – fascia plantaris (FP), the spring ligament complex (SLC) and interosseous talocalcaneal ligament (ITCL) – were sectioned sequentially. Joint kinematics were analysed for each condition, with and without force applied to TibPost.ResultsEliminating TibPost resulted in higher internal rotation of the calcaneus following the sectioning of FP and SLC (d>1.28, p = 0.08), while sectioning ITCL resulted in higher external rotation without TibPost (d = 1.24, p = 0.07). Sequential ligament sectioning induced increased flattening of Meary’s angle.ConclusionFunction of TibPost and medial ligaments is not mutually distinctive. The role of ITCL should not be neglected in flatfoot pathology; it is vital to section this ligament to develop flatfoot in cadaveric models.