Are enlarged peroneal tubercle and accessory anterolateral talar facet associated with calcaneal spur?

BACKGROUND: As the anatomical variations of the foot, enlarged peroneal tubercle (EPT) and accessory anterolateral talar facet (AALTF) have attracted the attention of foot surgeons in recent years. However, EPT and AALTF have not been examined for a relationship with calcaneus spur (CS) as a common osteophyte. METHODS: The subjects were 369 individuals who died in northeastern Thailand and were preserved as skeletal specimens. The authors examined for the presence of left and right EPT, AALTF, and calcaneus spur (CS). We divided the EPT (+) group with EPT and the EPT (-) group without it and also divided the AALTF (+) group with AALTF and the AALTF (-) group without it. The age at death and the presence of CS were compared statistically between the EPT (+) and EPT (-) groups and between the AATLF (+) and AALTF (-) groups. RESULTS: Out of the total 369 cases, EPT was found in 117 cases (31.7%), AALTF was positive in 91 cases (24.7%), and CS was found in 194 cases (52.3%). In comparison between EPT (+) and EPT (-) groups, CS was significantly higher (p < 0.0001) in the EPT (+) group, but there was no significant difference in age at death. In comparison between AALTF (+) and AALTF (-) groups, there was no significant difference in age at death or CS. CONCLUSION: This study showed a strong relationship between EPT and CS, and the prevalence of EPT and AALTF by age in Thailand was first reported. We believe it helps to know the pathogenesis and biomechanism of EPT and AALTF. TRIAL REGISTRATION: Not applicable.

Intraosseous myolipoma of the calcaneus.

A man in his 40s presented with an incidental finding of an osteolytic bone lesion. He sustained an ankle injury while inline skating, fracturing his lateral malleolus. Besides the fracture, radiographic imaging on the day of the injury incidentally revealed a well-defined solitary osteolytic lesion with a sclerotic rim within the right calcaneus. MRI showed an intraosseous, fat-containing lesion with focal contrast enhancement, assessed as an intraosseous lipoma with central necrosis. In the pathological analysis of a sample of the lesion an intraosseous myolipoma of the calcaneus was found-an unexpected and extraordinary finding. To prevent pathological fracturing, curettage and bone grafting were performed using autologous iliac crest bone in combination with allogenous bone chips.

New point-of-care calcaneal ultrasound densitometer (Osteosys BeeTLE) compared to standard dual-energy X-ray absorptiometry (DXA).

Dual-energy X-ray absorptiometry (DXA) represents the gold standard for measuring bone mineral density (BMD). However, its size and bulkiness limit its use in mass screening. Portable and easily accessible instruments are more suitable for this purpose. We conducted a study to assess the repeatability, sensitivity, accuracy, and validation of a new ultrasound densitometer for the calcaneus (OsteoSys BeeTLe) compared to standard DXA. BMD (g/cm2) was measured at the femoral and lumbar spine levels using DXA (Discovery Acclaim (Hologic, Waltham, MA, USA) or Lunar Prodigy (GE Healthcare, Madison, WI, USA) devices). Bone Quality Index (BQI, a dimensionless measure of bone quality derived from measures of SOS [Speed Of Sound] and BUA [broadband ultrasound attenuation]) was measured with OsteoSys BeeTLe. The Bland-Altman test and simple linear regression were used to evaluate the association between values measured with the two instruments. Additionally, the ability of the T-score calculated with BeeTLe to identify patients with previous osteoporotic fractures was tested using ROC curves. A total of 201 patients (94.5% females) with a mean age of 62.1 ± 10.2 were included in the study. The BeeTLe instrument showed a coefficient of variation (CV, in 75 repeated measurements) of 1.21%, which was not statistically different from the CV of DXA (1.20%). We found a significant association between BQI and BMD at the femoral neck (r2 = 0.500, p < 0.0001), total femur (r2 = 0.545, p < 0.0001), and lumbar spine (r2 = 0.455, p < 0.0001). T-scores bias were 0.215 (SD 0.876), 0.021 (SD 0.889) and 0.523 (SD 0.092), for femoral neck, total hip and lumbar spine respectively. AUC for discriminating fracture and non-fractured patients were not significantly different with OsteoSys BeeTLe and standard DXA. In this preliminary study, BeeTLe, a new point-of-care ultrasound densitometer, demonstrated good repeatability and performance similar to DXA. Therefore, its use can be proposed in screening for osteoporosis.

Beak-type fractures of the calcaneus.

Beak fractures represent a rare subtype of calcaneal fractures with potential risk of soft tissue complications due to compromised local perfusion. Early diagnosis and timely intervention are crucial to prevent necrosis, infection, and soft tissue defects. This case report describes a 71-year-old male with a beak fracture and delayed intervention with reoccurring soft tissue defects. Given the rarity of the condition, atypical presentation and need for urgent intervention, this emphasizes the importance of awareness of beak fractures of the calcaneus.

Biomechanical characteristics of Sanders type II and III calcaneal fractures fixed by open reduction and internal fixation and percutaneous minimally invasive fixation.

BACKGROUND: This work investigated the differences in the biomechanical properties of open reduction and internal fixation (ORIF) and percutaneous minimally invasive fixation (PMIF) for the fixation of calcaneal fractures (Sanders type II and III calcaneal fractures as examples) through finite element analysis. METHODS: Based on CT images of the human foot and ankle, according to the principle of three-point fixation, namely the sustentaculum tali, the anterior process and the calcaneal tuberosity were fixed. Three-dimensional finite element models of Sanders type II and III calcaneal fractures fixed by ORIF and PMIF were established. The proximal surfaces of the tibia, fibula and soft tissue were constrained, and ground reaction force and Achilles tendon force loads were added to simulate balanced standing. RESULTS: The maximum stress was 80.54, 211.59 and 113.88 MPa for the calcaneus, screws and plates in the ORIF group and 70.02 and 209.46 MPa for the calcaneus and screws in the PMIF group, respectively; the maximum displacement was 0.26, 0.21 and 0.12 mm for the calcaneus, screws and plates in the ORIF group and 0.20 and 0.14 mm for the calcaneus and screws in the PMIF group, respectively. The values obtained from the simulation were within the permissible stress and elastic deformation range of the materials used in the model, and there was no significant stress concentration. The maximum stress and displacement of the calcaneus and implants were slightly lower in the PMIF group than in the ORIF group when fixing Sanders type II and III calcaneal fractures. CONCLUSIONS: This study may provide a reference for optimising the design of implants, the development of individualised preoperative plans and the choice of clinical surgical approach.

Achilles Tendon Stiffness in the Etiology of Sever Disease: A Shear Wave Elastography Study.

BACKGROUND: Sever disease is one of the most common causes of heel pain in growing children and adolescents. There is no consensus about etiology of Sever disease. METHODS: The study comprised 41 participants aged 8 to 13 years who visited the orthopedic outpatient clinic: 17 patients with Sever disease and 24 asymptomatic children. The middle third segment of the body of the Achilles tendon and the calcaneal insertion zone were separately assessed. Five measuring points for the quantitative value of each point were randomly selected. The color scale used in the Young's modulus shows the lowest values in blue and the highest values in red. The mean values were used for the statistical analysis. RESULTS: Less elasticity was detected at the insertional site for the control group (4.02 kPa versus 3.65 kPa), the situation was reversed in the body of the Achilles tendon and the elasticity of the study group was less than that of the control group (241.0 kPa versus 260.5 kPa). However, no statistically significant difference was found between the groups. CONCLUSIONS: In conclusion, no difference was found in Achilles tendon elasticity between patients with Sever disease and healthy individuals in both the tendon body and the calcaneal insertionof the tendon. Achilles tendon elasticity has not been found to play a role in the etiology of Sever disease.

Osteopenia and Osteoporosis Screening Detection: Calcaneal Quantitative Ultrasound with and without Calibration Factor Comparison to Gold Standard Dual X-ray Absorptiometry.

BACKGROUND: osteoporosis is a worldwide major health problem that normally diagnosed in advanced stages. So, an early detection at preclinical stage is now an interesting issue. A key factor to early diagnosis the disease is the used of noninvasive bone densitometry. Dual energy x-ray absorptiometry (DXA) is the gold standard techniques for the proposed. However, the high cost, non-widely available and exposed to ionizing radiation are still a drawback of the machine. Therefore, a cheaper, smaller and non-ionizing device such quantitative ultrasound (QUS) is now a favor alternative method, but the possibility of used QUS measurement instead of DXA is still limited due to their uncertainties. So, the aim of our study was to calibrated the QUS with the DXA to allowing the possible to establish a calibration factor (CF) to improve the measured value closer to the standard method. METHODOLOGY: 135 healthy men and women aged 30-88 years were recruited for lumbar spine/femoral neck DXA and calcaneal QUS scanning. The Pearson's correlation between T- and Z-score from the two systems were studied. Moreover, the sensitivity, specificity and percentage of diagnosed accuracy for both with and without CF were calculated. RESULTS: The significant correlation between the two systems showed a positive trajectory in highly correlation (r = 0.784-0.899). Analyses showed a higher sensitivity, specificity and reduced the misdiagnosed rates when applied the CF in QUS values. CONCLUSIONS: QUS results showed a significantly correlated with DXA results for both lumbar spine and femoral neck sites with some percentage differences. These differences can be reduced by applied an individual specific machine CF to improve a QUS results. As identification of high risk of osteopenia and osteoporosis to reduce the demand of DXA propose, using a QUS alternative method can be a reliable that provide a cheaper and lack of ionizing radiation.

Age Estimation Using Machine Learning Algorithms with Parameters Obtained from X-ray Images of the Calcaneus.

BACKGROUND: Determination of bone age is a critical issue for forensics, surgery, and basic sciences. AIM: This study aims to estimate age with high accuracy and precision using Machine Learning (ML) algorithms with parameters obtained from calcaneus x-ray images of healthy individuals. METHOD: The study was carried out by retrospectively examining the foot X-ray images of 341 people aged 18-65 years. Maximum width of the calcaneus (MW), body width (BW), maximum length (MAXL), minimum length (MINL), facies articularis cuboidea height (FACH), maximum height (MAXH), and tuber calcanei width (TKW) parameters were measured from the images. The measurements were then grouped as 20-45 years of age, 46-64 years of age, 65 and older, and age estimation was made by using these at the input of ML models. RESULTS: As a result of the ML input of the measurements obtained, a 0.85 Accuracy (Acc) rate was obtained with the Extra Tree Classifier algorithm. The accuracy rate of other algorithms was found to vary between 0.78 and 0.82. The contribution of parameters to the overall result was evaluated by using the shapley additive explanations (SHAP) analyzer of Random Forest algorithm and the MAXH parameter was found to have the highest contribution in age estimation. CONCLUSIONS: As a result of our study, calcaneus bone was found to have high accuracy and precision in age estimations.

Biomechanical effects of Evans versus Hintermann osteotomy for treating adult acquired flatfoot deformity: a patient-specific finite element investigation.

BACKGROUND: Evans and Hintermann lateral column lengthening (LCL) procedures are both widely used to correct adult acquired flatfoot deformity (AAFD), and have both shown good clinical results. The aim of this study was to compare these two procedures in terms of corrective ability and biomechanics influence on the Chopart and subtalar joints through finite element (FE) analysis. METHODS: Twelve patient-specific FE models were established and validated. The Hintermann osteotomy was performed between the medial and posterior facets of the subtalar joint; while, the Evans osteotomy was performed on the anterior neck of the calcaneus around 10 mm from the calcaneocuboid joint surface. In each procedure, a triangular wedge of varying size was inserted at the lateral edge. The two procedures were then compared based on the measured strains of superomedial calcaneonavicular ligaments and planter facia, the talus-first metatarsal angle, and the contact characteristics of talonavicular, calcaneocuboid and subtalar joints. RESULTS: The Hintermann procedure achieved a greater correction of the talus-first metatarsal angle than Evans when using grafts of the same size, indicating that Hintermann had stronger corrective ability. However, its distributions of von-Mises stress in the subtalar, talonavicular and calcaneocuboid joints were less homogeneous than those of Evans. In addition, the strains of superomedial calcaneonavicular ligaments and planter facia of Hintermann were also greater than those of Evans, but both generally within the safe range (less than 6%). CONCLUSION: This FE analysis study indicates that both Evans and Hintermann procedures have good corrective ability for AAFD. Compared to Evans, Hintermann procedure can provide a stronger corrective effect while causing greater disturbance to the biomechanics of Chopart joints, which may be an important mechanism of arthritis. Nevertheless, it yields a better protection to the subtalar joint than Evans osteotomy. CLINICAL RELEVANCE: Both Evans and Hintermann LCL surgeries have a considerable impact on adjacent joints and ligament tissues. Such effects alongside the overcorrection problem should be cautiously considered when choosing the specific surgical method. LEVEL OF EVIDENCE: Level III, case-control study.

A Novel Technique of Medial Displacement Calcaneal Osteotomy Using the Intramedullary Fixation of a Conventional Low-Profile Locking Wedge Plate.

BACKGROUND: Postoperative heel pain arising from prominent screw heads is a common complication following medial displacement calcaneal osteotomy (MDCO). This study aims to present the clinicoradiographic outcomes of a novel MDCO technique, wherein intramedullary fixation of a conventional low-profile locking wedge plate is employed. METHODS: A retrospective analysis, involving a comparison of clinical and radiographic parameters among consecutive patients who underwent MDCO was conducted. The patients were subjected to either intramedullary wedge plate fixation through the osteotomy site (IWPF group, n = 45 cases) or conventional cannulated screw fixation from the heel (CCSF group, n = 51 cases). Radiographic evaluation included measurement of hindfoot alignment angle, alignment ratio, and moment arm. Clinical outcomes were measured with the American Orthopaedic Foot & Ankle Society ankle-hindfoot score, and the Foot and Ankle Ability Measure (FAAM) activities of daily living and sports subscales, before and at 6, 12, and ≥24 months postoperatively. The presence of heel pain was evaluated at the postoperative 6 and 12 months in both groups. RESULTS: For both groups, a marked enhancement in all 3 radiographic parameters was observed. The extent of correction for all clinicoradiographic parameters demonstrated no statistically significant divergence between the 2 groups. However, the FAAM-Sports scores at the 6-month postoperative juncture exhibited a significant elevation in the IWPF group relative to the CCSF group. Importantly, no patient reported heel pain at postoperative 6 and 12 months in the IWPF group whereas the rates of patients having heel pain at postoperative 6 and 12 months were 56.8% (29 cases) and 33.3% (17 cases), respectively, in the CCSF group. CONCLUSION: Both techniques yield analogous postoperative clinical and radiographic enhancements. However, the utilization of IWPF promotes a swifter clinical improvement with respect to sports activities when juxtaposed with the CCSF from the calcaneal tuberosity. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Impact of sustentaculum tali screw positioning on radiographic and functional outcomes in calcaneal fractures.

BACKGROUND: To investigate whether accurate placement of sustentaculum tali screws have the impacts on the clinical efficacy of calcaneal fractures. METHODS: A retrospective analysis of 72 cases (73 feet) of calcaneal fractures from September 2015 to September 2019 treated with open reduction and internal fixation with sustentaculum tali screws was conducted. Patients were divided into the sustentaculum tali fixation group (ST group) and the sustentaculum fragment fixation group (STF group) according to the location of the sustentaculum tali screw placement. The functional outcomes at preoperative, 7 days and 1 year postoperative were collected and analyzed. RESULTS: In the ST group (40 feet), the Gissane's angle altered from (109.89 ± 12.13)° to (121.23 ± 9.34)° and (119.08 ± 8.31)° at 7 days and 1 year postoperative, respectively. For Böhler's angles altered from (11.44 ± 5.94)°, to (31.39 ± 7.54)°, and (30.61 ± 7.94)° at 7 days and 1 year postoperative, respectively. In the STF group (33 feet), Gissane's angle altered from (110.47 ± 14.45)°, to (122.08 ± 8.84)°, and (120.67 ± 9.07)° and Böhler's angle altered from (11.32 ± 6.77)°, to (28.82 ± 8.52)°, and (28.25 ± 9.13)° (P < 0.001). However, there was no statistically significant difference in functional outcomes at 1 week after surgery and 1 year after surgery (P > 0.05). The AOFAS scores at the final follow-up of the two groups: ST group (88.95 ± 6.16) and STF group (89.78 ± 8.76); VAS scores, ST group (0.83 ± 0.98) and STF group (1.03 ± 1.59), all differences were not statistically significant (P > 0.05). CONCLUSION: The position of sustentaculum tali screws has no significant difference on the short-term clinical outcome in patients with calcaneal fractures, while reliable fixation of screws to sustentaculum tali fragment can achieve similar clinical outcome.

Accuracy of Cutaneous Landmarks Compared to Ultrasound to Locate the Calcaneal Footprint of the CFL.

The purpose was to determine the accuracy of the techniques of Lopes et al. and Michels et al., compared to ultrasound, to locate the center of the calcaneal footprint of the CFL in healthy volunteers. The authors recruited 17 healthy adult volunteers at 1 center with no current ankle pathologies and no previous surgical antecedents on either ankle. The authors recorded the age, sex, height, BMI, and ankle side for each volunteer. Measurements were made on both ankles of the 17 volunteers to increase the sample size and ensure less dispersion of data, independently by 2 surgeons: 1 senior surgeon with 15 years' experience and 1 junior with 3 years' experience. The location of the center of the calcaneal footprint of the CFL was determined by each surgeon using 3 methods: (1) the cutaneous technique of Lopes et al., (2) the cutaneous technique of Michels et al., and (3) ultrasound imaging. The 17 volunteers (34 feet) had a mean age of 26.3 ± 8.7 and a BMI of 21.7 ± 2.9. The Michels point was significantly closer (4.6 ± 3.7 mm) than the Lopes point (11.1 ± 5.4 mm) to the true center of the calcaneal footprint of the CFL determined by ultrasound, notably in the vertical direction. The Michels point was located significantly closer to the true center of the calcaneal footprint of the CFL and demonstrated less dispersion than the Lopes point, indicated by significantly lower absolute mean deviation from the true center of the calcaneal footprint of the CFL, and that ultrasound is therefore preferred to locate the footprint the CFL.

The role of patient positioning in surgical fixation of the calcaneus fractures using the lateral extensile approach.

INTRODUCTION: Calcaneus is the most commonly fractured tarsal bone. Open reduction and internal fixation of the displaced intra-articular fractures is considered the gold standard treatment. The lateral extensile approach is the most commonly used approach, and usually, the patients are kept in lateral decubitus position. Recent study has descried calcaneus fracture fixation utilizing the lateral extensile approach with the patient in prone position. The aim of this study was to compare the postoperative radiological outcome, reoperation rate, operative and anesthesia time, infection and the wound complications rate between the two groups. METHODS: The data of 49 adult patients with unilateral closed calcaneus fracture underwent open reduction and internal fixation using lateral extensile approach were collected. Postoperative Bohler's, Gissane angles and complications rate were compared between the two groups. RESULTS: A total of 49 patients were included. Lateral position was utilized in 26 patients (53.1%), while 23 patients (46.9%) were operated in prone position. Majority of the patients were males 87.8% (43 patients), and the mean age of the patients was 31.12 ± 7.50. The most commonly mechanism of injury was fall from height in (91.8%) of the patients. The mean preoperative Bohler's angle was 9.33 ± 13.07 and increased to 22.69 ± 9.15 postoperatively. The mean preoperative angle of Gissane was 130.45 ± 26.98 whereas it was 124.76 ± 17.20 postoperatively. The mean postoperative Bohler's angle and angle of Gissane were significantly higher among patient who underwent fixation in lateral position (25.88 ± 6.62, 137.15 ± 11.17) when compared to the prone one (19.09 ± 10.35, 110.74 ± 10.81). There was no significant difference between the two groups regarding the reoperation rate (p 0.947), infection (p 0.659, operative time (p 0.688), anesthesia time (p 0.522) and wound complications (p 0.773). CONCLUSION: Surgical restoration of the Bohler's and Gissane's angles with the patient placed in the lateral decubitus position remains superior to the prone position with no difference in the complication rate between the two groups.

Classification of intraarticular calcaneal fractures: comparison of two classification systems.

PURPOSE: Accurately classifying displaced intraarticular calcaneal fractures (DIACFs) is essential for orthopedic surgeons to choose optimal treatment methods and provide results evaluation and communication. Many authors studying used Sanders classification reported moderate intra- and interobserver reliability. Taking the software opportunity of 3D virtual exarticulation, Goldzak updated French tri-dimensional Utheza classification, providing an alternative framework for classifying DIACFs. The aim of this study was to compare the intra- and interobserver reliability of Sanders versus Goldzak classification systems. METHODS: The CT scans of 30 patients with displaced intraarticular calcaneal fractures, treated in the same trauma center between 2014-2018, were analyzed by 16 medical doctors (specialists and residents in orthopedic surgery, specialists and residents in radiology), and classified according to Sanders and Goldzak classifications. The same images were sent on two separate sessions, in a randomized order. Interobserver reliability and intraobserver reproducibility were assessed using Kappa statistics and Gwet's AC1 coefficient. RESULTS: Interobserver reliability using Gwet reported a value of 0.36 for Goldzak classification and 0.30 for Sanders classification (corresponding to "fair assessment" in both cases). In absence of subclasses, "substantial assessment" was reported for Goldzak classification (Gwet of 0.61) and "moderate assessment" for Sanders classification (Gwet of 0.46). Goldzak system had a greater interobserver reliability in the group of radiology residents. Intraobserver reliability coefficient was 0.60 for Goldzak classification and 0.69 for Sanders classification, indicating a substantial agreement for both classifications. CONCLUSION: Despite the better view of the fracture lines provided by 3D reconstructions, this study failed to prove the superiority of Goldzak classification compared to Sanders classification for DIACFs.

Relationship between dietary characteristics and heel quantitative ultrasound parameters in postmenopausal women from the OsteoLaus cohort.

The role of dietary patterns in the development of osteoporosis is unclear. The heel quantitative ultrasound (QUS) is a potential alternative to Dual X-Ray Absorptiometry. Nutrients, foods, dietary patterns and compliance to dietary guidelines were compared between the lowest and the highest tertiles of QUS parameters [Broadband Ultrasound Attenuation (BUA), Speed of Sound (SOS), Stiffness Index (SI)], using data from the OsteoLaus cohort. Participants in the highest tertiles of QUS parameters (385 for BUA, 397 for SOS, 386 for SI) were younger, of higher body weight, and had less major osteoporotic fractures. Women in the highest tertiles of SI and BUA consumed more fat (35.1 ± 0.4 vs 33.9 ± 0.4 and 34.9 ± 0.4 vs 33.8 ± 0.4 gr/day for SI and BUA, respectively, p < 0.05), and complied less frequently with dairy intake guidelines [odds ratio (95% confidence interval): 0.70 (0.53-0.92) and 0.72 (0.55-0.95) for SI and BUA, respectively, p < 0.05] than women in the lowest tertile. No differences were found regarding dietary patterns, healthy dietary scores, or compliance to dietary guidelines. Postmenopausal women in the highest QUS tertiles were younger, of higher weight and BMI, consumed more monounsaturated fatty acids and less dairy and calcium than women in the lowest tertiles. No differences were found between QUS tertiles regarding dietary patterns.

Factors influencing functional outcome of fractures of the anterior process of the calcaneus.

INTRODUCTION: Fractures of the anterior process of the calcaneus (APC) are easily overlooked in clinical practice. Most patients have good to excellent clinical outcome after conservative treatment, while some patients may have persisting symptoms and unfavorable functional outcomes. The aim of this study was to identify the risk factors associated with unfavorable functional outcome after conservative treatment in APC fractures. METHODS: All patients presenting with APC fractures and receiving conservative treatment from April 2019 to April 2020 were retrospectively assessed. The primary outcome measurement was the ankle joint function assessed using Karlsson Scoring System at 2 years post-injury. The risk factors associated with unfavorable functional outcomes (Karlsson score ≤ 80) were evaluated by logistic regression analysis. RESULTS: In total, 84 patients were included with a mean age of 40 years. 26 (31%) patients presented with unfavorable functional outcome at 2 years post-injury. In multivariate logistic regression, concomitant fractures of talonavicular (TN) joints and older age were significantly associated with unfavorable functional outcome (p<0.05). Patients with concomitant fractures of TN joints had an odds ratio of 3.623 for unfavorable functional outcome. The optimal cutoff age for an unfavorable outcome was ≥ 47.5 years, with an odds ratio of 5.010. CONCLUSION: Most patients with APC fractures achieved good to excellent results when treated conservatively. Attention should be paid to those with concomitant fractures of TN joints and with age ≥ 47.5 years, which might lead to unfavorable functional recovery. LEVEL OF EVIDENCE: IV; case series.

Effect of sequential burr passes on osteotomy magnitude and calcaneal morphology in minimally invasive Zadek osteotomy.

PURPOSE: This study aimed to evaluate the impact of each burr pass on degree of correction, gap size and calcaneal morphology in MIS Zadek osteotomy. METHODS: MIS Zadek osteotomy was performed on ten cadaveric specimens using a 3.1 mm Shannon burr. After each burr pass, the osteotomy gap was manually closed, and the subsequent burr passes were carried out with the foot held in dorsiflexion, which was repeated five times. Lateral X-rays were taken before and after each burr pass. Two independent reviewers measured the dorsal calcaneal length after each burr passage, as well as changes in several calcaneal parameters including X/Y ratio, Fowler Philip angle, and Böhler angle. RESULTS: The average decrease in dorsal calcaneal cortical length with each burr pass was as follows: 2.6 ± 0.9 mm at the 1st pass, 2.4 ± 1 mm at the 2nd pass, 2 ± 1 mm at the 3rd pass, 1.6 ± 1 mm at the 4th pass, and 1.4 ± 0.7 mm at the 5th pass. The Fowler Philip and Böhler angles consistently decreased while the X/Y ratio consistently increased following each consecutive burr pass. Interobserver reliability analysis demonstrated good agreement for all parameters. CONCLUSION: The results revealed the trends of length and anatomical changes in the calcaneus with each burr pass. On average, a dorsal wedge resection of 10 mm was achieved after 5 burr passes. This data can aid surgeons in determining the optimal number of burr passes required for a particular amount of resection, ensuring the attainment of the desired patient-specific surgical outcome.

The impact of sustentaculum tali fracture on clinical outcome in patients affected by isolated calcaneal fractures.

INTRODUCTION: The sustentaculum tali is displaced in almost half of calcaneal fractures and during surgical fixation represents one of the main reference points upon which the other bone has to be reduced. The purpose of this study was to investigate which subtalar joint fracture pattern is more frequently associated with sustentaculum tali involvement. Furthermore, correlation between postoperative clinical outcome and sustentaculum tali integrity was performed. MATERIAL AND METHODS: Patients with isolated calcaneal fractures were analyzed. Sanders-type fracture and involvement of both sustentaculum tali and calcaneocuboid joint were detected on computed tomography imaging; postoperative AOFAS scores were analyzed according to sustentacular involvement. RESULTS: Fifty calcaneus fractures in 47 patients were included in the final analysis. The sustentaculum tali was fractured in 18 cases (36.0%), thus contradicting its supposed constant position. Sanders type 3 and 4 fractures were more frequently associated with fractured sustentaculum than type 2 (p = 0.012). Sanders type 4 fractures were associated with displaced sustentacular fragment significantly more than type 2 and 3 (p = 0.043). Patients with intact sustentaculum tali reported significantly higher (p < 0.001) mean AOFAS scores than the uninjured group (84.4 ± 9.1 and 74.3 ± 9.5, respectively). CONCLUSION: Sanders type 3 and 4 fractures were more frequently associated with sustentaculum tali and/or calcaneocuboid joint involvement than simpler fractures. Injury of sustentaculum tali was related to significant worse postoperative clinical outcomes, underlying the relevance of this fragment on clinical course.

Development of a semi-anthropomorphic photoacoustic calcaneus phantom based on nano computed tomography and stereolithography 3D printing.

Osteoporosis is a major public health threat with significant physical, psychosocial, and financial consequences. The calcaneus bone has been used as a measurement site for risk prediction of osteoporosis by noninvasive quantitative ultrasound (QUS). By adding optical contrast to QUS, our previous studies indicate that a combination of photoacoustic (PA) and QUS, that is, PAQUS, provides a novel opportunity to assess the health of human calcaneus. Calibration of the PAQUS system is crucial to realize quantitative and repeatable measurements of the calcaneus. Therefore, a phantom which simulates the optical, ultrasound, and architectural properties of the human calcaneus, for PAQUS system calibration, is required. Additionally, a controllable phantom offers researchers a versatile framework for developing versatile structures, allowing more controlled assessment of how varying bone structures cause defined alterations in PA and QUS signals. In this work, we present the first semi-anthropomorphic calcaneus phantom for PAQUS. The phantom was developed based on nano computed-tomography (nano-CT) and stereolithography 3D printing, aiming to maximize accuracy in the approximation of both trabecular and cortical bone microstructures. Compared with the original digital input calcaneus model from a human cadaveric donor, the printed model achieved accuracies of 71.15% in total structure and 87.21% in bone volume fraction. Inorganic materials including synthetic blood, mineral oil, intralipid, and agar gel were used to model the substitutes of bone marrow and soft tissue, filling and covering the calcaneus phantom. The ultrasound and optical properties of this phantom were measured, and the results were consistent with those measured by a commercialized device and from previous in vivo studies. In addition, a short-term stability test was conducted for this phantom, demonstrating that the optical and ultrasound properties of the phantom were stable without significant variation over 1 month. This semi-anthropomorphic calcaneus phantom shows structural, ultrasound, and optical properties similar to those from a human calcaneus in vivo and, thereby, can serve as an effective source for equipment calibration and the comprehensive study of human patients.

External fixation in intra-articular fractures of the calcaneus: Is it a valid option as definitive treatment?

INTRODUCTION: The therapeutic management of calcaneal fractures is currently a major source of controversy in the literature. There is no consensus on the need to treat these injuries conservatively or surgically, nor on the criteria for deciding one option or the other. Although the gold standard has classically been the open approach and osteosynthesis, there are currently minimally invasive techniques that also report good results. Our objective is to present our results and experience with the MBA® Orthofix external fixator in a series of cases of calcaneal fractures. METHODS: We performed a retrospective observational study in our center, between the years 2019 and 2021, of Sanders types II-IV calcaneal fractures operated with MBA® Orthofix external fixator. We recorded a total of 38 patients, 42 fractures. We registered demographic information, intraoperative, postoperative, radiological and functional parameters, using the American Orthopedic Foot and Ankle Society (AOFAS), Manchester-Oxford Foot Questionnaire (MOXFQ), EQ-5D and VAS scales. RESULTS: A total of 26 men and 12 women were included, and the median age was 38 years. Mean follow-up was 24,4 months (6, 8-40, 1). The average time to surgery was 7 days and partial loading was started at 2.5 weeks after external fixation, which was removed at 9.2 weeks. The average Böhler angle correction was 7, 4°, Gissane - 12,2°, length 2 mm and calcaneal width was reduced by 5 mm. We recorded two superficial infections, one peroneal entrapment and three subtalar arthrodesis due to post-traumatic osteoarthritis. The AOFAS obtained was 79.1 + / - 15.7 points, MOXFQ 20.1 + / - 16.1 points, EQ-5D 0.84 + / - 0.2 and VAS 3.3 + / - 1.9. CONCLUSION: The external fixator is an excellent surgical alternative for complex articular fractures of the calcaneus, obtaining clinical and radiological results comparable to other osteosynthesis techniques and significantly reducing soft tissue complications.