Percutaneous treatment of calcaneus fractures associated with underlying bone cysts

Primary tumours of the calcaneus

The calcaneus is a rare location for the occurrence and development of primary tumour types. Clinicians are unfamiliar with calcaneal tumour types, which may result in a delay in diagnosis or a missed diagnosis, resulting in unnecessary morbidity and amputation. Heel pain and localized swelling of the ankle are the most common symptoms. X-ray is the first choice for a tentative diagnosis of a calcaneal tumour. The final diagnosis depends on a histological examination. The treatment of calcaneal tumour types varies depending on the Enneking system. The majority of patients with benign tumours heal, except for a few with a palindromia. For malignant tumours, the prognosis is comparatively poor, resulting in disability and a high rate of metastasis. This review describes the spectrum of calcaneal tumour types and specifically illustrates the epidemiology, symptomatology, imagology, histopathology and treatment options that may facilitate diagnosis and improve prognosis.

The role of orthobiologics in foot and ankle surgery: Allogenic bone grafts and bone graft substitutes

Orthobiologics are biological substances that are used therapeutically for their positive effects on healing skeletal and soft-tissue injuries. The array of orthobiological products currently available to the foot and ankle surgeon is wide, and includes bone allografts, bone substitutes, growth factors, and chondral scaffolds. Nonetheless, despite the surge in interest and usage of orthobiologics, there remains a relative paucity of research addressing their specific applications in foot and ankle surgery. In this review, we attempt to provide an overview of the literature on commonly available allogenic bone grafts and bone substitutes.

There is Level II, III and IV evidence addressing allogenic bone grafts in primary arthrodesis and osteotomy procedures in foot and ankle surgery, which compares favourably with autogenic bone grafts in terms of fusion rates and clinical outcomes (often with fewer complications), and supports a Grade B recommendation for its use.

Pertaining to bone substitutes, the multiplicity of products, coupled with a lack of large prospective clinical trials, makes firm recommendations difficult. Level II and IV studies of calcium phosphate and calcium sulphate products in displaced intra-articular calcaneal fractures have found favourable results in addressing bone voids, maintaining reduction and promoting union, meriting a Grade B recommendation. Evidence for TCP is limited to level IV studies reporting similarly good outcomes in intra-articular calcaneal fractures, warranting a Grade C recommendation. The use of demineralised bone matrix products in hindfoot and ankle fusions has been described in Level II and III studies, with favourable results in achieving fusion and good clinical outcomes, supporting a Grade B recommendation for these indications.

Overall, despite the general lack of high-level evidence in foot and ankle surgery, allogenic bone grafts and bone substitutes continue to hold front-line roles in treating the bone defects encountered in trauma, tumour, and deformity correction surgery. However, more investigation is required before firm recommendations can be made.

Cite this article: EFORT Open Rev 2017;2:272–280. DOI: 10.1302/2058-5241.2.160044

Validation of the Dutch language version of the Foot and Ankle Outcome Score

PURPOSE

The aim of this study was to develop a Dutch language version of the Foot and Ankle Outcome Score (FAOS-DLV) and evaluate its measurement properties according to the definitions of the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN).

METHODS

After a standard forward-backward translation procedure, the Dutch version of the FAOS was evaluated for reliability and validity in 110 patients with various hind foot and ankle complaints. Reliability was evaluated by calculation of intraclass correlation coefficients (ICC), Cronbach's alpha for internal consistency, and the smallest detectable change (SDC). Construct validity of the FAOS was assessed by calculation of Spearman's correlation coefficients with similar and dissimilar domains of the SF-36 health survey, American Orthopedic Foot and Ankle Society Ankle and Hindfoot Scale, and visual analogue scales for pain and disability. Dimensionality was tested with confirmatory factor analysis.

RESULTS

Reliability of the FAOS-DLV was good. The ICC of the subscales ranged from 0.83 to 0.88. The minimal value of Cronbach's alpha was 0.76. The SDC at individual level ranged from 18 to 21 and at group level between 2.1 and 2.5. Construct validity was supported by confirmation of 85 % of the hypothesized correlations. Unidimensionality of the FAOS-DLV domains was moderate.

CONCLUSION

The Dutch version of the FAOS seems to have acceptable measurement properties. The questionnaire can be used for functional assessment of patients with varying hindfoot and ankle symptoms. It is, however, more suitable for clinical evaluation at group level than for monitoring a specific patient.

LEVEL OF EVIDENCE

Diagnostic study, Level I.

Translation and validation of the German version of the foot and ankle outcome score

PURPOSE

Outcome assessment is critical in evaluating the efficacy of orthopaedic procedures. The Foot and Ankle Outcome Score (FAOS) is a 42-item questionnaire divided into five subscales, which has been validated in several languages. Germany has no validated outcome score for general foot and ankle pathology. The aim of this study was to develop a German version of the FAOS and to investigate its psychometric properties.

MATERIALS AND METHODS

Forward and backward translation was executed according to official guidelines. The final version of the FAOS was investigated in 150 patients with various foot and ankle disorders. All patients completed the FAOS, Short Form-36, numeric rating scales for pain and disability, and the Hannover questionnaire. The FAOS was re-administered after 1 week. Test-retest reliability, internal consistency, minimal detectable change, construct validity, and floor and ceiling effects were analyzed.

RESULTS

Test-retest reliability and internal consistency of each subscale were excellent (intraclass correlation coefficient, 0.88-0.95; Cronbach's α, 0.94-0.98). The minimal detectable changes of each subscale were 17.1-20.8 at the individual level and 2.0-2.4 at group level. There were moderate to strong correlations between FAOS subscales and physical outcomes and low to moderate correlations between FAOS subscales and mental outcomes. Floor and ceiling effects were not present.

CONCLUSION

The German version of the FAOS is a reliable and valid instrument for use in foot and ankle patients.

Morphology effect of bioglass-reinforced hydroxyapatite (Bonelike(®) ) on osteoregeneration

In the last decades, the well-known disadvantages of autografts and allografts have driven to the development of synthetic bone grafts for bone regeneration. Bonelike(®) , a glass-reinforced hydroxyapatite (HA) composite was developed and registered for bone grafting. This biomaterial is composed by a modified HA matrix, with α- and β-tricalcium phosphate secondary phases. Aiming to improve the biological characteristics of Bonelike(®) , new spherical pelleted granules, of different shape and size, were developed with controlled micro and macrostructure. In the present study, it was compared the physicochemical properties and in vivo performance of different Bonelike(®) granule presentations-Bonelike(®) polygonal (500-1000 µm size) and Bonelike spherical (250-500 µm; 500-1000 µm size). For the in vivo study, Bonelike(®) was implanted on sheep femurs, with various implantation times (30 days, 60 days, 120 days, and 180 days). X-ray diffraction analysis revealed that the phase composition of different granules presentations was similar. Bonelike(®) spherical 500-1000 µm was the most porous material (global porosity and intraporosity) and Bonelike(®) polygonal 500-1000 µm the less porous. Considering the in vivo study, both polygonal and spherical granules presented osteoconductive proprieties. The spherical granules showed several advantages, including easier medical application through syringe and improved osteointegration, osteoconduction, and degradation, by the presence of larger pores, controlled micro- and macrosctructure and suitable particle format that adapts to bone growth. Bonelike(®) spherical 500-1000 µm showed improved new bone invasion throughout the material's structure and Bonelike(®) spherical 250-500 µm appeared to induce faster bone regeneration, presenting less unfilled areas and less lacunae in the histological analysis.