Arthroereisis and Pes planovalgus. Tool of the devil or novel implant?

BackgroundThe primary aim of surgical flatfoot management is to correct deformity, provide dynamic support to the medial longitudinal arch and stabilise the hindfoot to allow normal heelstrike and propulsion for toe off. The correction aims to place the calcaneal tuberosity in line with the midsagittal tibia and reduce the talonavicular joint.Materials and MethodsThe standard procedure involves a heel cord lengthening or calf release if indicated. Bony correction involves a varising calcaneal osteotomy. The medial soft tissue correction involves repair of the tibialis posterior tendon and augmentation with a flexor digitorum longus tendon transfer. The arthroereisis implant is inserted into the sinus tarsi via a 2 cm skin incision over a guide wire. The primary role of the arthroereisis is to block the non-physiologic eversion of the subtalar joint by limiting pronation. Thus, the implant acts as an internal arch support, protecting the medial soft tissue repair.ResultsThe senior author has reviewed 84 feet over 7 years of late stage tibialis posterior dysfunction treated in the above technique. No infections were recorded and 30% of implants were removed after 6 months for subtalar discomfort. Less favourable outcome was associated with over- or undersizing of the implant.ConclusionArthroereisis allows for a good correction adult onset pes planovalgus. It provides an additional tool in the armamentarium of the foot and ankle surgeon for the management of a difficult condition     

Talar neck fracture—A rare but important complication following subtalar arthroereisis

Subtalar arthroereisis is a technique for treating symptomatic flexible flatfeet by means of inserting an implant or stent into the sinus tarsi. The goals are to reduce pain, deformity and instability of the foot.However, there are recognised complications associated with this technique which include malposition of the implant, undercorrection/overcorrection of the deformity, persistent sinus tarsi pain, deep medial heel pain, foreign body synovitis, avascular necrosis of the talus, intraosseous cystic formation in the talus, migration of the implant, device extrusion and subtalar joint arthrosis.In this report an unusual complication of fracture of the neck of the talus in a teenager who competes recreationally in ‘at risk’/impact sports, who had previously had arthroereisis screw insertion some years before is presented.     

Das Sinus-tarsi-Syndrom

Sinus tarsi syndrome, described by O'Connor in 1958 and Brown in 1960, is a clinical finding often seen after an accident, consisting of a painful reaction to pressure on the sinus tarsi. This syndrome has also been described in dancers, volleyball and basketball players, overweight individuals, and patients with foot deformities (flatfoot). We looked for mechanical and functional macroscopic structures in the canalis and sinus tarsi that can be associated with sinus tarsi syndrome in order to deduce therapeutic consequences.We found a complex fibrous layer in the sinus and canalis tarsi that forms slips around the synovial sheats of the extensor tendons under the inferior extensor retinaculum. Both limbs run deep to the base of the sinus and canalis tarsi. The lateral band inserts into the sinus tarsi at the calcaneus, while the medial band inserts at the canalis tarsi at the talus and calcaneus. Instead of the term "interosseous ligaments," we recommend referring to the "fundiform ligament" with one lateral and one medial band.Regarding function, one can assume that the medial band of these fundiform ligaments controls the talus at eversion and inversion together with the well-vasculated and well-innervated interarticular fat pads in the sinus and canalis tarsi. While contracting the long extensor muscles of the toes, the ligament forms a control mechanism for the longitudinal arch of the foot in the moving phase.A question is how variations in vascularization or disorders in innervation will alter the turgor of the pads of fat tissue. That is, such alterations would influence the distribution of synovia in the neighboring joints as well as the tension of the involved ligaments.     

How does the postoperative medial arch height influence the patient reported outcomes of stage Ⅱ acquired adult flatfoot deformity?

BackgroundThis study aimed to assess how the postoperative medial arch height influenced postoperative patient-reported clinical outcomes after surgery for stage Ⅱ acquired adult flatfoot deformity.MethodsA total of 30 feet of 30 patients (7 males, 23 females) who underwent surgery for stage Ⅱ acquired adult flatfoot deformity and could be followed up for at least 2 years were included. The average age at surgery was 60.0 (standard deviation, 13.0) years, and the average follow-up period was 40 (standard deviation, 15.4) months. Among them, 16 patients underwent lateral column lengthening and 14 patients did not. Patient-reported clinical outcomes were evaluated using the Self-Administered Foot Evaluation Questionnaire. Radiographic alignment was evaluated by the talonavicular coverage angle, lateral talo-1st metatarsal angle, medial cuneiform height, medial cuneiform to 5th metatarsal height, and calcaneal pitch. The correlation between postoperative Self-Administered Foot Evaluation Questionnaire and radiographic alignment was assessed with Pearson's correlation analysis.ResultsSelf-Administered Foot Evaluation Questionnaire and radiographic alignment significantly improved postoperatively in all patients (P < 0.0001). In patients with severe deformity who needed lateral column lengthening, lateral talo-1st metatarsal angle was negatively and medial cuneiform to 5th metatarsal height was positively correlated with physical functioning Self-Administered Foot Evaluation Questionnaire subscales (r = ?0.56 and 0.55), and medial cuneiform height was positively correlated with physical functioning, social functioning and general health Self-Administered Foot Evaluation Questionnaire subscales (r = 0.70, 0.55 and 0.73, respectively).ConclusionPostoperative medial arch height could influence physical functioning, social functioning, and general health in patients with severe stage II adult-acquired flatfoot deformity.     

Spontaneous Subtalar Fusion: An Irreversible Complication of Subtalar Arthroereisis

Subtalar arthroereisis has been used for the treatment of symptomatic flexible flatfoot deformities in both pediatric and adult patients. Chronic sinus tarsi pain is the most common complication of this procedure and can be relieved by removal of the implant. We describe a case of spontaneous fusion of the subtalar joint after arthroereisis. This is an irreversible complication that should be described to the patient as a rare, but possible, outcome of arthroereisis of the subtalar joint.     

HyProCure跗骨螺钉治疗成年人柔韧性扁平足早期疗效分析

背景：成人柔韧性扁平足的有效治疗方法目前仍存在争议。距跗关节稳定机制这一概念的提出和HyProCure跗骨螺钉的发明,给成人柔韧性扁平足治疗带来了新的理念和方法。目的：评价HyProCure跗骨螺钉治疗成年人柔韧性扁平足的早期临床疗效。方法：2012年9月至2013年3月,对27例（34足）成人柔韧性扁平足患者采用HyProCure跗骨螺钉实施距下关节稳定术治疗。男20例,女7例,年龄18-77岁,平均（33．8±11．6）岁。术后定期随访,随访内容包括临床并发症评估、x线和CT检查及基于PACS5．0系统的图像测量,并采用美国足踝外科协会（American Orthopedic Foot and Ankle Society,AO—FAS）踝与后足功能评分和视觉模拟评分（visual analogue score,VAS）进行术后疗效评定。结果：所有患者均获随访,随访时间3-6个月,平均（4．7±1．8）个月。除1例术后1个月因HyProCure脱出跗骨窦行更换手术外,余无明显围手术期并发症发生。随访期间无一例永久移除HyProCure。手术前后距骨第1跖骨角（14．1°±6．0°vs 4．7°±2．8°,P〈0．01）、跟骨倾斜角（16．1°±2．0°VS20．4°±2．2°,P〈0．05）、距舟覆盖角（24．9°±3．3°vs15．0°士2．1°,P〈0．01）和距骨第2跖骨角（32．3°±4．2°VS14．6。土1．9。,P〈0．01）改善明显,患足内侧纵弓高度显著提升（P〈0．01）,VAS疼痛评分明显改善（P〈0．05）,术后AOFAS踝与后足功能评分较术前提高了74．9％（44．2±11．1w77．3±10．7,P〈0．01）。结论：采用HyProCure跗骨螺钉治疗成年人柔韧性扁平足可以有效恢复正常足部骨性结构关系、手术创伤小、术后可早期负重、患足疼痛改善明显、功能提高显著,但远期疗效仍需进一步观察。     

Calcaneo-stop procedure for paediatric flexible flatfoot

Background  

Flexible flatfoot is a frequent deformity found in children. The aim of this study is to evaluate the pedographic outcome of the percutaneous arthroereisis with the use of a screw through the sinus tarsi into the talus.     

The severe flexible flatfoot: a combined reconstructive procedure with rerouting of the tibialis anterior tendon.

A combined procedure is described that addresses all the components at fault in the severely flexible flatfoot deformity in children. The Evans calcaneal distraction wedge osteotomy will lengthen the lateral column, correcting the heel valgus and forefoot abduction. A naviculo--first cuneiform wedge resection (medial and plantar) and fusion will shorten and reshape the collapsed medial arch. This is augmented by reconstruction and plication of the lengthened plantar ligaments, with plantar rerouting of the tibialis anterior tendon to act as a strong plantar ligament. In addition, shifting the tibialis anterior's pull proximally acts as a sling to the talar head. Z plasty of the tight tendo Achillis is always needed. Nineteen feet in 11 patients were the subject of this study. The period of follow-up ranged from 8 to 42 months. The results were assessed according to the relief of foot strain and calf pains, improvement in shoewear, general activity, and foot shape. To evaluate foot shape, reconstruction of the medial arch and heel posture were assessed. The children and parents were satisfied with the final results in 17 feet (89.5%). Improvement of the radiological measurements was evident and was statistically significant.     

Subtalar arthroereisis for posterior tibial tendon dysfunction: a preliminary report

BACKGROUND: The purpose of this study was to evaluate preliminary results with Kalix subtalar arthroereisis in sinus tarsi for stage II posterior tibial tendon dysfunction. METHODS: Twenty-one patients with stage II posterior tibial dysfunction, according to Johnson and Storm, underwent surgical treatment between July 1999 and December 2000. All patients were evaluated clinically using the America Orthopaedic Foot and Ankle Society (AOFAS) hindfoot-ankle score. We performed a tendon repair depending on the type and location of the injury and implanted a Kalix endorthesis in the sinus tarsi. RESULTS: Nineteen patients attended for clinical review with an average follow-up of 27.31 months (range, 19-36). AOFAS scale improved from a preoperative average of 47.2 to an average of 81.6 at revision. The most important improvement was observed in pain (16.3 preoperative to 31.6 postoperative). Two cases required removal of the endorthesis for pain, probably because the endorthesis was too big, without any loss of correction. Patient satisfaction was "satisfied" or "very satisfied" in 17/19. All except three patients would have elected to undergo the same procedure. CONCLUSIONS: Subtalar arthroereisis by means of implantation of a Kalix endorthesis in the sinus tarsi, with prior correction of the deformity and tendon repair, offers an alternative to bone operations such as calcaneal osteotomies, lengthening the external column, or arthodesis in patients with stage II posterior tibial dysfunction.     

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.     

Is There a Role for Subtalar Arthroereisis in the Management of Adult Acquired Flatfoot?

Subtalar arthroereisis, often combined with Achilles tendon lengthening, is a simple and effective way to treat flexible flatfoot in adults. The most common complication is pain in sinus tarsi, which usually disappears after removal of the implant. Midterm results are good and it does not hinder other treatments in the future.     

成人获得性平足的软组织重建

目的总结成人获得性平足(adult-acquired flatfoot deformity,AAFD)软组织重建的基础和临床研究进展。方法广泛查阅近年关于AAFD软组织修复和肌腱转移的相关文献,并进行综述。结果针对AAFD的软组织重建手术可分为静力性和动力性重建两种,其中静力性重建以弹簧韧带的修复重建为主;动力性重建术式较多,趾长屈肌腱转移术常用,但其生物力学效果欠佳,对于胫后肌功能正常的患者Cobb手术效果更佳。结论对于AAFD需根据畸形类型和分期选择软组织重建术式。     

Lateral column osteotomy versus subtalar arthroereisis in the correction of Grade IIB adult acquired flatfoot deformity: A clinical and radiological follow-up at 24 months

BackgroundAdult acquired flat foot deformity (AAFD) is a spectrum of conditions which can be progressive if untreated. Surgical correction and restoration of anatomical relationship are often required in the treatment of symptomatic Grade II AAFD after a failed course of conservative treatment. There is a paucity of literature recommending best practice–especially in the adult population. The authors aim to compare radiological and clinical outcomes of two widely employed surgical techniques in the treatment of symptomatic AAFD.MethodsA retrospective study of 76 patients with Grade IIB AAFD and had undergone either lateral column lengthening (LCL) or subtalar arthroereisis (STA) surgical correction of their symptomatic AAFD. Each technique was augmented with both bony osteotomy and soft tissue transfer as determined by on table assessment. Clinical and radiological outcomes were reviewed 24 months after surgery.ResultsLCL and STA groups had comparable radiological outcomes at 24 months after surgery. However, LCL group demonstrated superior American Orthopaedic Foot and Ankle Society (AOFAS) midfoot (90.3 ± 12.6 vs 81.1 ± 20.6, p < 0.001) as well as Visual Analogue Scale (VAS) midfoot scores (0.5 ± 1.6 vs 1.3 ± 2.4, p < 0.001) at 24 months compared to the STA group. STA had a higher complication rate (20.6% vs 4.4%), with all cases complaining of sinus tarsi pain requiring subsequent removal of implant.ConclusionThere is a role for either techniques in the treatment of symptomatic AAFD. LCL whilst more invasive has demonstrated superior outcome scores and lower complication rates at 24 months compared to STA. Patients need to be counselled appropriately to appreciate the benefits of each technique.     

Arthroereisis for Symptomatic Flexible Flatfoot Deformity in Young Children: Radiological Assessment and Short-Term Follow-Up

The purpose of this study is to recognize those young patients with symptomatic flexible flatfoot deformity who need treatment and to provide radiological evidence that arthroereisis is capable of relocating the talus properly over the calcaneus. We included 28 feet in 14 children who underwent subtalar arthroereisis in association with percutaneous triple-hemisection Achilles tendon lengthening. Selected for arthroereisis were children with symptomatic flexible flatfoot deformity who complained of foot and leg pain, had decreased endurance in sports activities and long walks, who did not respond to conservative treatment modalities for at least 6 months, and in whom at radiological assessment on stance position with the medial arch support orthosis the talonavicular joint lateral subluxation still remained, with Meary's angle in anteroposterior (A/P) and lateral view remaining increased. The mean age at surgery was 10.71 ± 1.58 (range 8 to 14) years. The minimum follow-up duration was 19 months, with mean follow-up duration of 35.14 ± 9.82 (range 19 to 60) months. For estimation of the efficacy of the surgical procedure, the American Orthopaedic Foot and Ankle Society (AFOAS) rating scale was used preoperatively and postoperatively in all patients. The mean preoperative AFOAS ankle-hind foot rating score was 65.14 ± 7.16 (range 58 to 75) points. The mean postoperative AFOAS score was 88.851 ± 5.61 (range 83 to 97) points and the 2-tailed p value <.0001. After arthroereisis surgical treatment, all AOFAS scores and all foot angles improved significantly, except the calcaneal inclination angle which improved slightly.     

Radiographic Analysis of the Lateral Column Lengthening Procedure in Stage II Adult Acquired Flatfoot Deformity

Adult acquired flat foot deformity (AAFD) is a progressive, tri-planar deformity involving collapse of the medial longitudinal arch, valgus deformity of the rear foot, and abduction of the mid-foot on the rear foot. There are a wide variety of surgical treatment options for this deformity, including lateral column lengthening (LCL) which results in tri-planar correction of AAFD. We retrospectively reviewed weightbearing preoperative radiographs and weight-bearing 6-week postoperative radiographs of 34 patients with stage II AAFD who underwent LCL (with and without concurrent procedures) with a minimum of 1-year of follow up. Outcomes, including complications and postoperative differences in 6 types of angle measurements were evaluated. Radiographic evaluation showed statistically significant differences in preoperative and postoperative measures in the following angles: calcaneal inclination, Meary's, Simmons, talocalcaneal, and metatarsus adductus (each p ≤ .05). Postoperative Engel's angle difference did not reach statistical significance (p = .07). Paired t tests showed TN coverage angles increased greater with LCL plus a Cotton osteotomy as compared to isolated LCL. Additionally, there was no significant difference in TN coverage angle based on LCL graft size (p = .20). Furthermore, the distance of the osteotomy from the calcaneocuboid joint on anteroposterior and lateral radiographs did not significantly predict TN coverage angle change.Our study suggests that LCL corrects AAFD in three planes while decreasing the metatarsus adductus angle. LCL appears to be more effective when performed with a Cotton osteotomy. Wedge size (6 mm, 8 mm, 10 mm) and osteotomy location did not demonstrate a relationship with postoperative TN coverage angle or incidence of lateral column overload.     

Subtalar arthroereisis and its role in pediatric and adult population

Subtalar joint arthroereisis is a surgical procedure that addresses symptomatic flexible flatfoot deformities using an extraarticular implant within the sinus tarsi. Three groups of implants have been developed for this procedure: self-locking wedges, axis-altering devices, and impact-blocking devices. The self-locking wedge implants are the focus of this article, relative to its use, limitations, and controversies in the pediatric and adult population.     

Dynamic medial column stabilization using flexor hallucis longus tendon transfer in the surgical reconstruction of flatfoot deformity in adults

BackgroundA common challenge in flatfoot reconstruction arises when there are multiple locations of collapse within the medial column. An extension of arthrodesis may lead to complications such as stiffness or adjacent joint arthritis. The purpose of this study was to report outcomes of flatfoot reconstruction using the dynamic medial column stabilization (DMCS) technique, which transfers the flexor hallucis longus (FHL) tendon to the first metatarsal base to support the entire medial column.MethodsWe retrospectively reviewed 14 consecutive patients (14 feet) who underwent DMCS as an adjunct to flatfoot reconstruction. In all cases, a medial displacement calcaneal osteotomy and gastrocnemius recession were performed to address hindfoot valgus deformity and heel cord tightness, respectively. Deformity correction was assessed using preoperative and postoperative weightbearing radiographs. The newly defined metatarsal-cuneiform articular angle (MCAA) and naviculo-cuneiform articular angle (NCAA) were measured to assess correction at each medial column joints. Clinical outcomes included the FFI and VAS scores. Any complications related to the surgery were investigated.ResultsAll radiographic parameters significantly improved postoperatively. The sagittal plane correction occurred at all three joints within the medial column. Clinically, both FFI and VAS improved significantly at the final follow-up. One patient developed plantar pain under the first metatarsal head that may have been associated with the overtightening of the transferred tendon.ConclusionDMCS using FHL tendon transfer to the first metatarsal base was a useful technique for restoring the medial arch and correcting three planar deformities in the setting of flatfoot deformity.     

Biomechanical evaluation of the efficacy of external stabilizers in the conservative treatment of acquired flatfoot deformity

This study quantified and compared the efficacy of in-shoe orthoses and ankle braces in stabilizing the hindfoot and medial longitudinal arch in a cadaveric model of acquired flexible flatfoot deformity. This was addressed by combining measurement of hindfoot and arch kinematics with plantar pressure distribution, produced in response to axial loads simulating quiet standing. Experiments were conducted on six fresh-frozen cadaveric lower limbs. Three conditions were tested: intact-unbraced; flatfoot-unbraced; and flatfoot-braced. Flatfoot deformity was created by sectioning the main support structures of the medial longitudinal arch. Six different braces were tested including two in-shoe orthoses, three ankle braces and one molded ankle-foot orthosis. Our model of flexible flatfoot deformity caused the calcaneus to evert, the talus to plantarflex and the height of the talus and medial cuneiform to decrease. Flexible flatfoot deformity caused a pattern of medial shift in plantar pressure distribution, but minimal change in the location of the center of pressure. Furthermore, in-shoe orthoses stabilized both the hindfoot and the medial longitudinal arch, while ankle braces did not. Semi-rigid foot and ankle orthoses acted to stabilize the medial longitudinal arch. Based on these results, it was concluded that treatment of flatfoot deformity should at least include use of in-shoe orthoses to partially restore the arch and stabilize the hindfoot.     

Flexible flatfoot in children and adolescents

Flexible flatfoot is a normal foot shape that is present in most infants and many adults. The arch elevates spontaneously in most children during the first decade of life. There is no evidence that a longitudinal arch can be created in a child’s foot by any external forces or devices. Flexible flatfoot with a short Achilles tendon, in contrast to simple flexible flatfoot, is known to cause pain and disability in some adolescents and adults. Joint-preserving, deformity-correcting surgery is indicated in flexible flatfeet with short Achilles tendons when conservative measurements fail to relieve pain under the head of the plantar flexed talus or in the sinus tarsi area. Osteotomy is the fundamental and central procedure of choice. In almost all cases, Achilles tendon lengthening is required. In some cases, rigid supination deformity of the forefoot is present, requiring identification and concurrent treatment.     

A surgical approach for flexible flatfeet in adults including a subtalar arthroereisis with the MBA sinus tarsi implant

BACKGROUND: The purpose of this study was to determine the functional outcomes and radiographic results of adult patients who had an operation for flexible flatfeet without any hindfoot osteotomies or fusions. METHODS: Twenty-eight feet in 23 patients with problems caused by their flexible flatfoot deformities had reconstructive foot and ankle surgery that included a subtalar arthroereisis (the restriction of the range of motion of a joint) with the Maxwell-Brancheau Arthroereisis (MBA) sinus tarsi implant. The American Orthopedic Foot and Ankle Society (AOFAS) Hindfoot Scale and a patient assessment questionnaire were obtained from all patients before surgery and at final follow-up. Preoperative and postoperative standing radiographs were analyzed to determine radiographic correction of the deformities. The average followup was 44 months. The MBA implant was surgically removed in 11 of 28 feet (39%) because of sinus tarsi pain. RESULTS: The average preoperative AOFAS score was 52 and had improved to 87 (p<0.00001) at final followup. The average response to four of five questions in the patient assessment had significantly improved (p<0.05). On a 10-point scale, average patient satisfaction was 8.3 points; 78% said that they would have the surgery again. Correction after surgery was significant (p<0.0001) in each of the three radiographic parameters evaluated for 'correction with MBA' and 'final correction.' With the numbers available, no significant differences could be detected after the MBA was removed. Complications included sinus tarsi pain in 46% (13) of the 28 feet in this study; after implant removal, 73% (8) of 11 feet had less discomfort than before surgery with AOFAS scores 80 or better. CONCLUSIONS: Reconstructive foot and ankle surgery that included a subtalar arthroereisis with the MBA sinus tarsi implant resulted in favorable clinical outcomes and patient satisfaction in 78% (18) of 23 patients. In spite of the high incidence of temporary sinus tarsi pain until the implant was removed, this operative approach compares favorably with other operations for flexible flatfoot deformities in adults.