Tarsal coalition in adults.

Adult tarsal coalition consists in abnormal union of two or more tarsal bones. Reported incidence ranges between 1 and 13%. It is generally a congenital condition, due to dominant autosomal chromosome disorder, but with some acquired forms following trauma or inflammatory pathology. Poorly specific clinical signs and the difficulty of screening on conventional X-ray may lead to diagnostic failure. The present review of tarsal coalition addresses the following questions: how to define tarsal coalition? How to diagnose it? How to treat it? And what results can be expected? There are 3 types of tarsal coalition, according to the type of tissue between the united bones: bony in pure synostosis, cartilaginous in synchondrosis, and fibrous in syndesmosis. Location varies; the most frequent forms are talocalcaneal (TC) and calcaneonavicular (CN), accounting for more than 90% of cases. Cuneonavicular, intercuneal and cuboideonavicular locations are much rarer, at less than 10%. Tarsal coalition is classically painful, often with valgus spastic flatfoot in young adults. The pain is caused by the biomechanical disturbance induced by the bone, cartilage or fibrous bridges which partially or completely hinder hindfoot and/or midfoot motion. Conventional imaging, with weight-bearing X-ray and CT, is standard practice. Weight-bearing CT is increasingly the gold standard, displaying abnormalities in 3 dimensions. Functional imaging on MRI and tomoscintigraphy assess direct and indirect joint impact at the affected and neighboring joint lines. Non-operative treatment can be proposed, with orthoses, rehabilitation and/or injections. But surgery is the most frequent option: either resection of the bony, cartilaginous or fibrous constructs to restore optimally normal anatomy, or arthrodesis in the affected joint line or the entire joint. Surgery can be open, arthroscopic or percutaneous, depending on the severity of the biomechanical impact on the affected and neighboring joints. Resecting the abnormality is the standard practice in all locations if it affects less than 50% of the talocalcaneal joint line and there is no osteoarthritis to impair the functional outcome. Otherwise, fusion is required. Level of evidence: V; expert opinion.

Review of the role of bone-SPECT/CT in tarsal coalitions.

Tarsal coalition (TC) is a congenital abnormal connection (fibrous, cartilaginous, or osseous) between two or more bones in the hind and midfoot, mostly consisting of calcaneonavicular or talocalcaneal coalition, and is often asymptomatic. However, TCs may result in foot motion limitation and pain with or without flatfoot (pes planus), arising in adolescents and young adults. Appropriate imaging is needed to pinpoint foot pain in the (suspected) TC, starting with plain radiographs. Still, normal radiographs do not exclude TCs. Computed tomography (CT) and MRI are frequently used advanced imaging techniques. CT alone has known limited sensitivity in cartilaginous and fibrous TCs and correlation between CT abnormalities and pain may be challenging, as solely anatomical changes in TCs are often asymptomatic. MRI can depict soft tissue abnormalities in TC with high accuracy. Nonetheless, after the implantation of metallic osteosynthesis material, MRI is often limited due to image distortion, signal loss, and misregistration. Bone scintigraphy with [99mTc]Tc-diphosphonate single photon emission computed tomography/CT (bone-SPECT/CT) is a known sensitive tool to detect osteoblastic bone pathology. However, the literature concerning bone-SPECT/CT in TC patients is limited. This article reviews bone-SPECT/CT patterns in TCs, how it complements other imaging techniques and their relation to clinical complaints. Bone-SPECT/CT excels in accurate bone pathology characterization in TC, confidently excluding synchronous lesions elsewhere, and offering optimal insight into osseous structures and 3D-localization of bone metabolism for surgery planning. Furthermore, even with implanted osteosynthesis material, bone-SPECT/CT can pinpoint the culprit pain generator, where MRI is either contra-indicated or considerably hampered.

A retrospective magnetic resonance imaging analysis of bone and soft tissue changes associated with the spectrum of tarsal coalitions.

We aimed to investigate the bone and soft tissue changes accompanying tarsal coalition (TC) and aimed to evaluate their association with the location and type of coalition. Ankle magnetic resonance imagings of 65 patients with TC were included. The relationship between the location and type of coalition and bone marrow edema, subchondral cysts, sinus tarsi syndrome, tarsal tunnel syndrome, posterior impingement syndrome, accessory bone, tibiotalar effusion, talar osteochondritis dissecans, ganglion cysts, and calcaneal spur were evaluated. Twenty-nine patients without coalition were selected as the control group, and the distribution of these variables between the two groups was analyzed. There were 33 females and 32 males in the coalition group (mean age: 42.0 ± 15.63 years), and 22 females and seven males in the control group (mean age: 44.79 ± 12.33 years). Coalition was most common in the talocalcaneal joint (n = 33, 50.8%), and the most common coalition type was non-osseous (n = 57, 87.6%). We find no significant difference between the pathologies defined in terms of coalition location and type. Sinus tarsi syndrome, tarsal tunnel syndrome, subchondral cysts, and tibiotalar effusion were found to be more common in the coalition group (p = 0.028, p = 0.010, p = 0.023, and p = 0.006, respectively). The presence of coalition increased the probability of developing tarsal tunnel syndrome 9.91 times (95% CI: [1.25-78.59]; p = 0.029), and sinus tarsi syndrome 3.66 times (95% CI: [1.14-11.78]; p = 0.029). Tarsal coalition may predispose bone and soft tissue changes. In this study, sinus tarsi syndrome, tarsal tunnel syndrome, subchondral cysts and tibiotalar effusion were found to be more common in the coalition group.

Cubonavicular Coalition in a Middle-Aged Woman: A Case Report.

Cubonavicular coalition is a rare type of tarsal coalition that can be described as osseous or nonosseous (fibrous, cartilaginous, or fibrocartilaginous). Typically, it manifests symptoms during adolescence, as it presents with pain at the Mid-hindfoot and with decreased range of motion at the midtarsal joints, hindfoot valgus deformity, or peroneal spasm. Here, we present a rare case of cubonavicular coalition in a middle-aged woman with atypical presentation and a review of the literature. We conclude that this abnormality should be taken into account in the differential diagnosis of mid-hindfoot pain, even in middle-aged adults.

Racial differences in prevalence and anatomical distribution of tarsal coalition.

Previous studies have reported a prevalence of tarsal coalition of 0.03-13%. Calcaneonavicular coalition is known as main anatomical type, and the bilateral occurrence of tarsal coalition is known to be 50% or more. These are the results of studies on Caucasians, there have been few studies targeting large number of East Asians so far. We hypothesized that the prevalence and characteristics of tarsal coalition in East Asians might differ from those in Caucasians. The medical records of 839 patients who underwent bilateral computed tomography on foot and ankle in our hospital from January 2012 to April 2021 were retrospectively reviewed. The overall prevalence was 6.0%, talocalcaneal coalition was the most common anatomical type. The overall bilateral occurrence was 56.5%, talocalcaneal coalition had the highest bilateral occurrence (76.0%) among anatomical types. Isolated union of the posterior facet was the most common subtype of talocalcaneal coalition (43.2%). Talocalcaneal coalition had a significantly higher proportion of coalition-related symptomatic patients than calcaneonavicular coalition (p = 0.019). Our study showed a similar trend to other East Asian studies, confirming the existence of racial differences. The possibility of tarsal coalition in foot and ankle patients in East Asians should always be considered, and bilateral examination is essential for diagnosis.

Tarsal coalition resections: a long-term retrospective analysis of 97 resections in 78 patients.

BACKGROUND: Resection of tarsal coalitions provides good patient satisfaction scores, reduced pain, and improved long-term function in both athletic and non-athletic populations. This study aimed to determine when athletic patients undergoing resection of a tarsal coalition were able to return to their desired activity, and whether they experienced a decreased desired activity level (DDA). METHODS: Data on a total of 78 patients who underwent 97 tarsal coalition resections (49 talocalcaneal coalitions, 47 calcaneo-navicular, 14 cuboid-navicular, and three cuneo-navicular; some patients had more than one coalition) operated between January 2001 and June 2020 were prospectively collected. To subjectively assess outcomes, the Roles and Maudsley score (RM) was utilized. RESULTS: At an average follow-up from the index procedure of 33.6 ± 41.5 months, return to activity for the entire cohort was 18.3 ± 9.6 weeks. Post-RM was 1.3 ± 0.6. CONCLUSION: Surgical excision of tarsal coalitions produced favorable results, with most patients able to return to their desired activity level. LEVEL OF EVIDENCE: IV.

Talocalcaneal Tarsal Coalition Size: Evaluation and Reproducibility of MRI Measurements.

BACKGROUND: The size of talocalcaneal tarsal coalitions (TCCs) is one of the main factors that is thought to influence patient outcomes after resection. Magnetic resonance imaging (MRI) is increasingly being used to diagnose and characterize TCCs. However, there is no reproducible MRI-based measurement of TCC size reported in the literature. The purpose of this study was to create a method to reproducibly measure TCC size using MRI. METHODS: Twenty-seven patients with TCCs diagnosed by a hindfoot coronal proton density (PD) MRI between 2017 and 2020 were included. Five independent raters measured coalition width, healthy posterior facet width, and healthy middle facet width on individual slices of coronal PD hindfoot MRIs using discrete MRI measurement guidelines. Individual slice measurements were summed to determine total size of the coalition and the remaining healthy cartilage of the posterior and middle facets. Inter-rater reliability of MRI measurements between the 5 independent examiners was evaluated using intraclass correlation coefficient (ICC). ICC was calculated for total coalition width, total healthy posterior facet width, total coalition width/total healthy posterior facet width, total coalition width/total healthy middle facet width, total coalition width/total healthy subtalar facet width (posterior facet+middle facet), and total coalition width/total subtalar facet width (coalition+posterior facet+middle facet). RESULTS: The ICC scores for all but one of the MRI measurements indicated good to excellent inter-rater reliability among the 5 examiners. The ICC was 0.932 (95% confidence interval: 0.881-0.966) for measurement of total coalition width/total healthy posterior facet width and 0.948 (95% confidence interval: 0.908-0.973) for measurement of total coalition width/total subtalar facet width (middle+posterior+coalition). CONCLUSIONS: Measurements of coalition size using novel MRI guidelines were reproducible with good to excellent inter-rater reliability. These guidelines allow for determination of TCC size using coronal PD MRI. LEVEL OF EVIDENCE: Level II-diagnostic reproducibility study.

Bone stress injuries in the presence of tarsal coalition as a cause of hindfoot pain in adolescents: case series of 6 patients with literature review.

OBJECTIVE: To highlight causal relationship between stress fracture in the presence of tarsal coalition and hindfoot pain in adolescents on magnetic resonance imaging (MRI). MATERIAL AND METHODS: A retrospective review was performed of the clinical and MRI imaging findings of 6 adolescents referred for MRI to evaluate symptoms of hindfoot pain with possible tarsal coalition. MRI studies were systematically assessed for cause of hindfoot pain, types of tarsal coalition, patterns of stress fractures, bone marrow oedema and any other associated features. RESULTS: All the 6 patients (4 male: 2 female) aged between 12 and 19 years developed insidious onset of hindfoot or midfoot pain over a period of weeks to months. On MRI, all 6 cases had features of fibrous tarsal coalition predominantly in the calcaneonavicular articulation (5 out of 6 patients). Associated stress fractures/response were in the posterior facet/body of the calcaneus (3), talar head (2), cuboid (1) and third metatarsal bone in one patient. CONCLUSION: Stress fractures/response adjacent to tarsal coalition could be because of altered biomechanics and can be an unusual cause of hindfoot pain in adolescents. A high index of suspicion and complementary MRI findings is crucial to interpret this condition to direct appropriate patient management.

Osteochondritis dissecans of the talar dome in patients with tarsal coalition.

OBJECTIVE: Tarsal coalition is known to cause abnormal talocrural stress, hindfoot malalignment, and ankle sprains. These can all be associated with osteochondritis dissecans (OCD) of the talar dome. We present the first detailed description of a series of talar OCDs occurring in patients with tarsal coalition, with the goal of determining whether there is an increased prevalence of OCDs among patients with tarsal coalition. MATERIALS AND METHODS: We studied ankle MRIs in 57 patients with tarsal coalitions, excluding those with a reported inciting traumatic event. The MRIs were performed on magnetic field strengths ranging from 0.3 to 1.5 T and included axial, coronal, and sagittal T1 and T2 or PD fat-suppressed sequences. We evaluated the morphology and location of classically described OCDs in these patients, type and location of concomitant tarsal coalition, and, when available, the presence of pes planus and hindfoot valgus on weight-bearing radiographs. Chi-squared analysis was used to compare categorical variables and a Student's t test was used for parametric continuous variables. Additionally, logistic regression was used to compute the odds ratio of talar OCD associated with patient age, gender, laterality, pes planus status, hindfoot valgus status, and coalition type. RESULTS: Eighty-nine percent of tarsal coalitions were non-osseous coalitions and the calcaneonavicular space was the most common site of abnormal tarsal connection (54.4%). In the 29 patients with tarsal coalitions and talar OCDs, OCDs commonly occurred medially (75.9%). In the sagittal plane, talar OCDs occurred centrally, with only one case sparing the central talar dome. The mean surface area of the 29 OCDs was 89.7 mm2. Both osseous coalition and hindfoot valgus were associated with smaller talar OCD mean surface area (p = 0.015 and p = 0.0001, respectively). There was no association between depth and surface area of talar OCD with either coalition location or presence of pes planus (coalition location: p = 0.455 for depth and p = 0.295 for surface area; presence of pes planus: p = 0.593 for depth and p = 0.367 for surface area). CONCLUSION: Talar OCD prevalence is higher in patients with tarsal coalition than that reported for the general population. This occurrence may relate to altered biomechanics and repetitive talocrural stress owing to altered subtalar motion, particularly given the findings of increased odds of talar OCD in older patients, as well as weak associations between OCD surface area and both non-osseous coalition and hindfoot alignment. However, we did not find any specific OCD morphologic features attributable to the precise location of the tarsal coalition.

Tarsal Coalitions.

Tarsal coalitions are recognized as a congenital anomaly whereby the two or more bones of the hindfoot and midfoot are fused resulting in limitation of foot motion and pain. Tarsal coalitions were found to be the cause of painful flatfeet in adolescents and young adults. Developing a clinical understanding of tarsal coalitions as well as developing a step-wise conservative and surgical approach for their treatment can alleviate patient symptomatology and provide excellent long-term benefits. Conservative treatment consists of immobilization, NSAIDs, and casting for symptomatic patients, and surgical treatment for symptomatic tarsal coalition consists of resection and/or arthrodesis.

Surgical Treatment of Calcaneonavicular and Talocalcaneal Coalitions.

Tarsal coalition is determined by an absence of segmentation between one or more foot bones. The main symptom is activity-related foot pain, usually dorsolateral for calcaneonavicular coalitions and medial for talocalcaneal ones. At presentation, a symptomatic tarsal coalition must be treated conservatively for at least 6 months. If the conservative treatment fails and the foot is still painful, resection is the treatment of choice. Advantage of surgery is to restore mobility and reduce the risk of subsequent degenerative arthritis. Common pitfalls of surgery include failure to recognize associated coalitions, inadequate or extensive resection, and injury of adjoining bones.

Management of Complex Tarsal Coalition in Children.

Complex tarsal coalition includes extensive talocalcaneal coalition, double or triple coalition, coalition with severe hindfoot deformities, or coalition with a ball-and-socket ankle deformity. Careful preoperative physical examination including diagnostic injection is important in treatment planning. Both radiographic examination and computed tomographic scan that involve not only the foot but also the ankle are necessary to analyze the location and size of the coalitions, determining the presence of arthritis in the involved or adjacent joints, and if there are any deformities including a ball-and-socket ankle, which is frequently associated with complex tarsal coalitions.

Prospective Evaluation of Tarsal Coalition Excision Show Significant Improvements in Pain and Function.

BACKGROUND: Excision of pediatric tarsal coalition has been successful in most patients. However, some patients have ongoing pain after coalition excision. This study prospectively assessed patient-based clinical outcomes before and after surgical excision of tarsal coalition, with particular emphasis on comparison to radiologic imaging. METHODS: We prospectively studied 55 patients who had symptomatic coalition excision for 2 years postoperatively. Patients filled out the modified American Orthopaedic Foot and Ankle Society score, the University of California Los Angeles activity score, and the simple question "does foot pain limit your activity" at 4 different time points: preoperative, 6 months postoperative, 12 months postoperative, and 24 months postoperative. Comparisons were done utilizing patient demographics, imaging parameters, and patient-reported outcomes. RESULTS: Compared with preoperative levels, patients showed improvements in all outcome parameters. Patients with calcaneonavicular coalitions showed initial rapid improvement with later slight decline, while patients with talocalcaneal coalitions showed more steady improvement; both were similar at 2 years postoperatively. CONCLUSIONS: This prospective study demonstrated remarkable clinical improvements after tarsal coalition excision regardless coalition type, though postoperative courses differed between calcaneonavicular and talocalcaneal types. Finally, a subset of patients has ongoing activity limiting foot pain after coalition excision which could not be explained by the data in this study. LEVEL OF EVIDENCE: Level II-prospective cohort study.

Mal-union of sustentaculum tali fracture with talo-calcaneal coalition leading to tarsal tunnel syndrome: A case report.

Displaced isolated fractures of sustentaculum tali are rare. Inadequate treatment of these injuries can rarely lead to non-union or mal-union and in most cases are treated non-surgically. We report a unique case of undiagnosed mal-union of sustentaculum tali in the setting of underlying tarsal coalition that resulted in symptoms of tarsal tunnel. Osteotomy and excision of the mal-united fragment and coalition along with decompression of the tarsal tunnel was performed. The patient had immediate improvement in pain and the paraesthesia recovered by the end of 6 weeks post-operatively. The Foot and Ankle disability score (FADI) score improved from 26.0 pre-operatively to 96.2 at 3 years' follow-up. This case highlights that isolated fractures of sustentaculum tali warrant advanced imaging and surgical reduction and fixation may be appropriate to avoid long-term disability where displacement compromises the tarsal tunnel or function of the subtalar joint.

Sustentaculum Tali Fracture Adjacent to Talocalcaneal Tarsal Coalitions: A Report of 2 Cases.

CASE: An 11-year-old boy demonstrated chronic medial hindfoot pain. A 12-year-old boy experienced acute pain and swelling in his right medial ankle and hindfoot after a fall. This is the first report of sustentaculum tali fractures adjacent to a talocalcaneal tarsal coalition, likely resulting from a stress riser created by a rigid subtalar joint. CONCLUSION: These 2 cases represent unique causes of foot pain in the setting of tarsal coalitions, never before described. Patient-reported outcome measures demonstrated expected improved outcomes after excision of tarsal coalition. Awareness to this possibility will help clinicians treating foot and ankle conditions in children optimize their care.

Tarsal Coalition of the Cuneiforms in a Young Athlete: A Case Report.

CASE: Tarsal coalitions are relatively common, but there are no reports of cuneiform-to cuneiform coalition in the English language literature. The authors present a case of medial-to-intermediate cuneiform coalition in a young female track athlete. Previous nonoperative treatments had been unsuccessful. Coalition release and medial-intermediate cuneiform arthrodesis enabled her to return initially to full athletic participation without pain, but she had return of pain that persists despite removal of hardware. CONCLUSION: Medial-intermediate cuneiform coalition is rare. Surgery in this patient provided a short period of pain-free athletic participation, but long-term outcomes are not proven, and further research is needed.

The role of ultrasonography in the diagnosis of talocalcaneal coalitions.

BACKGROUND: Patients with talocalcaneal coalitions (TCC) often undergo computed tomography (CT). However, ultrasonography diagnosis of TCC has been seldom done according to the literature. PURPOSE: To investigate the accuracy of ultrasonography in diagnosing TCC compared to CT. MATERIAL AND METHODS: Ninety-seven consecutive patients with a clinical suspicion of TCC were included. Ultrasonography was used to assess the classification and complication of TCC. The main sonographic criteria for a positive diagnosis in cases of osseous coalition were the joint space between the medial surface of talar head and the underlying sustentaculum tali of calcaneus disappearing and being replaced by a continuous hyperechoic bony structure. In cases of fibrous coalition, ultrasonography revealed a reduced space of the joint associated with an irregular, angular appearance of its outline and hypoechoic fibrous tissue inside. These data were compared with CT findings. κ statistic was applied to determine the level of agreement. The sensitivity, specificity, positive and negative predictive values, accuracy, and Youden index of ultrasonography as a diagnostic method were assessed. RESULTS: Ultrasonography findings were positive in 20 of 97 patients with a clinical suspicion of TCC. The diagnosis was confirmed by CT in 21 patients. There were one false-positive result and two false-negative results by ultrasonography. The κ value was 0.907. The sensitivity, specificity, positive and negative predictive values, accuracy, and Youden index of ultrasonography were 90.5%, 98.7%, 95.0%, 97.4%, 96.9%, and 0.892, respectively. CONCLUSION: Ultrasonography could be a reliable, accurate, and non-radioactive diagnostic imaging method in diagnosis of patients with suspected TCC.

Ankle Ganglion Associated with Tarsal Coalition: A Case Report with a 5-Year Follow-up.

CASE: Talocalcaneal coalition (TCC) is a common type of coalition, often neglected. This case is of a 10-year-old girl with a painful ankle mass, diagnosed with TCC and a ganglion cyst. Examination revealed stiff subtalar motion, a submalleolar prominence, and well-circumscribed, tender mass at the posteromedial ankle. Treatment options include short period of casting/observation, excision vs. aspiration of the cyst, resection of the TC coalition, or a combination of the above. She underwent TCC resection with cyst aspiration. CONCLUSION: At the 5-year follow-up, the patient's examination and imaging revealed normal motion without cyst recurrence, indicating resolution of the cyst with coalition resection.