Surgical treatment of calcaneal fractures with use of beta-tricalcium phosphate ceramic grafting

Temporal comparison of radiological and functional outcomes in calcaneal fracture surgery with and without iliac crest graft application: Mid- to long-term results

BACKGROUND

The standard approach for addressing intra-articular calcaneal fractures involves open reduction with plate and screw fixation, with ongoing discourse regarding the application of grafts to address bone gaps. The aim of this study is the temporal comparison of the radiological and functional outcomes in patients undergoing surgery for intra-articular calcaneal fractures, with a specific focus on the use of bone grafts.

METHODS

Thirty patients, comprising 13 with iliac grafts and 17 without, were enrolled in the study. Preoperative and postoperative assessments included Gissane and Böhler angles, Visual Analog Scale (VAS) scores, American Orthopedic Foot and Ankle Society (AOFAS) ankle hindfoot scale, and Kellgreen-Lawrance subtalar arthrosis stages. The average follow-up period was 6.7 years, ranging from a minimum of 3.5 to a maximum of 10 years.

RESULTS

The Böhler angle exhibited a significant increase (p < 0.001), while the Gissane angle did not show significant changes in the early postoperative period across the entire study group (p = 0.1). Graft-treated patients demonstrated a significantly higher Böhler angle in the early and late postoperative periods compared to preoperative values (p = 0.04, p = 0.05). Similarly, patients without grafts exhibited a significantly higher Böhler angle in the early and late postoperative periods compared to preoperative values (p = 0.004, p = 0.002). No significant differences were observed between periods in Gissane measurements (p = 0.3), VAS scores, AOFAS scores, and the development of subtalar arthrosis in both grafted and non-grafted patients.

CONCLUSIONS

Evaluation of patients with calcaneal fractures, both with and without grafts, was conducted using Böhler and Gissane angles, VAS scores, AOFAS scores, and the development of fracture union and subtalar arthrosis, assessing preoperative, early, and late postoperative periods. No significant differences were found between the two groups in terms of clinical and radiological outcomes during mid-to long-term follow-up.

LEVEL OF EVIDENCE

A retrospective cohort study.

Biomechanical role of bone grafting for calcaneal fracture fixation in the presence of bone defect: A finite element analysis

BACKGROUND

The purpose of this study was to compare the biomechanical stress and stability of calcaneal fixations with and without bone defect, before and after bone grafting, through a computational approach.

METHODS

A finite element model of foot-ankle complex was reconstructed, impoverished with a Sanders III calcaneal fracture without bone defect and with moderate and severe bone defects. Plate fixations with and without bone grafting were introduced with walking stance simulated. The stress and fragment displacement of the calcaneus were evaluated.

FINDINGS

Moderate and severe defect increased the calcaneus stress by 16.11% and 32.51%, respectively and subsequently decreased by 10.76% and 20.78% after bone grafting. The total displacement was increased by 3.99% and 24.26%, respectively by moderate and severe defect, while that of posterior joint facet displacement was 86.66% and 104.44%. The former was decreased by 25.73% and 35.96% after grafting, while that of the latter was reduced by 88.09% and 84.78% for moderate and severe defect, respectively.

INTERPRETATION

Our finite element prediction supported that bone grafting for fixation could enhance the stability and reduce the risk of secondary stress fracture in cases of bone defect in calcaneal fracture.

Is it necessary to graft the void defect during open reduction and internal fixation of calcaneal fractures?

PURPOSE

There are still controversies on the effect of grafting during open reduction and internal fixation of calcaneal fractures. The aim of this study was to compare the radiological and functional outcomes in patients with or without intraoperative grafting.

METHODS

In a comparative retrospective study, among 442 operatively-treated calcaneal fractures, 60 patients with unilateral closed sanders type II intraarticular calcaneal fracture who underwent ORIF via lateral extensile approach using locking anatomical plates with at least 1 year follow-up without any postoperative wound complication were enrolled. The patients were separated into 2 groups: with bone allograft and without bone allograft. The functional outcome of the patients was assessed using visual analog scale (VAS) for pain, the American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale, foot function index (FFI), and short-form (SF-36) health survey. Radiographic variables included Böhler angle, Gissane angle, calcaneal width, calcaneal height, and talar declination angle. Also, the differences (delta) of these values in comparison to the uninjured foot were calculated.

RESULTS

The mean age was 39.1 ± 12.7 (range, 13-67) years with 54 males, 90.0%. No statistically significant differences were detected in age, gender, affected side, and subtypes of calcaneal fractures between the two groups (p > 0.05). The average follow-up was 25.1 (range, 12-48) months. The differences for all radiographic measurements and also, the delta values between the groups were not statistically significant, except talar declination angle which was more in cases without grafting (p = 0.007). Although the differences between the two groups regarding AOFAS ankle-hindfoot scale (p = 0.257), VAS for pain (p = 0.645), and FFI (p = 0.261) were not statistically significant; the group with bone graft experienced less pain (19.7 ± 22.0) than the other group (26.7 ± 22.8). The difference between the groups was not statistically significant (p = 0.87) according to the SF-36 questionnaire.

CONCLUSIONS

Incorporating allografts into the void defects during ORIF of displaced intraarticular calcaneal fractures may not improve functional outcomes and recover postoperative radiological parameters. Therefore, routine use of allograft to fill the defects during ORIF of calcaneus may not be recommended. Of note, that these findings solely relate to the treatment of Sanders type II fractures.

LEVEL OF EVIDENCE III

Comparative retrospective study.

Alveolar Repair Using Cancellous Bone and Beta Tricalcium Phosphate Seeded With Adipose-Derived Stem Cell

INTRODUCTION

Adipose-derived stem cells (ADSCs) have been subject of several studies due to their abundance, ease of preparation, and application in bone regeneration. We aim to compare effectiveness of alveolar reconstruction utilizing human cancellous freeze-dried graft (HCG) and beta tricalcium phosphate (BTP), both seeded with human ADSC (hADSC) and autologous bone graft (ABG).

MATERIAL AND METHODS

A 5 × 5 mm alveolar defect in 36 male Wistar rats were treated using: ABG (C), HCG-hADSC (H1), and BTP-hADSC (H2). At 1 and 8 weeks after surgery, runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), osterix (OSX), and bone morphogenetic protein 2 (BMP2; g/mL) were quantified using immunohistochemistry, while bone tissue volume (BV, mm3), bone tissue volume fraction (BF, percentage), and trabecular thickness of bone (TT, mm) were assessed using micro-computed tomography (CT).

RESULTS

One week after surgery, H2 was higher in RUNX2, OSX, ALP, and BMP2 than C (P < .05). Only RUNX2 and OSX were found to be higher in H1 than C, while ALP and BMP2 were higher in H2 than H1. Micro-CT revealed that H2 had a higher TT than C and C had a higher TT than H1 (P < .05). Eight weeks after surgery, both H2 and H1 was higher in RUNX2, OSX, ALP, and BMP2 than C (P < .05). RUNX2 and BMP2 were found to be higher in H1 than H2. Micro-CT revealed that H2 had higher BV and TT than C and H1 (P < .05).

CONCLUSIONS

Exogenous hADSC strengthened the effectiveness of HCG and BTP to accelerate osteogenesis, osteoconduction, and osteoinduction. The latter was the most successful in bone formation, followed by HCG and ABG.

Nonoperative and Operative Soft-Tissue and Cartilage Regeneration and Orthopaedic Biologics of the Foot and Ankle: An Orthoregeneration Network Foundation Review

Orthoregeneration is defined as a solution for orthopaedic conditions that harnesses the benefits of biology to improve healing, reduce pain, improve function, and optimally, provide an environment for tissue regeneration. Options include drugs, surgical intervention, scaffolds, biologics as a product of cells, and physical and electromagnetic stimuli. The goal of regenerative medicine is to enhance the healing of tissue after musculoskeletal injuries as both isolated treatment and adjunct to surgical management, using novel therapies to improve recovery and outcomes. Various orthopaedic biologics (orthobiologics) have been investigated for the treatment of pathology involving the foot and ankle (including acute traumatic injuries and fractures, tumor, infection, osteochondral lesions, arthritis, and tendinopathy) and procedures, including osteotomy or fusion. Promising and established treatment modalities include 1) bone-based therapies (such as cancellous or cortical autograft from the iliac crest, proximal tibia, and/or calcaneus, fresh-frozen or freeze-dried cortical or cancellous allograft, including demineralized bone matrix putty or powder combined with growth factors, and synthetic bone graft substitutes, such as calcium sulfate, calcium phosphate, tricalcium phosphate, bioactive glasses (often in combination with bone marrow aspirate), and polymers; proteins such as bone morphogenic proteins; and platelet-derived growth factors; 2) cartilage-based therapies such as debridement, bone marrow stimulation (such as microfracture or drilling), scaffold-based techniques (such as autologous chondrocyte implantation [ACI] and matrix-induced ACI, autologous matrix-induced chondrogenesis, matrix-associated stem cell transplantation, particulated juvenile cartilage allograft transplantation, and minced local cartilage cells mixed with fibrin and platelet rich plasma [PRP]); and 3) blood, cell-based, and injectable therapies such as PRP, platelet-poor plasma biomatrix loaded with mesenchymal stromal cells, concentrated bone marrow aspirate, hyaluronic acid, and stem or stromal cell therapy, including mesenchymal stem cell allografts, and adipose tissue-derived stem cells, and micronized adipose tissue injections. LEVEL OF EVIDENCE: Level V, expert opinion.

Bone graft versus non-bone graft for treatment of calcaneal fractures: A protocol for meta-analysis

BACKGROUND

Calcaneal fractures are a prevalent form of injury caused by high-energy trauma. This study aimed at investigating whether bone graft and non-bone graft are essential for the internal fixation of calcaneal fractures. A meta-analysis of relevant clinical studies evaluated radiographic parameters, functional outcomes, and complications that offer practical recommendations on the suitability of bone grafts for the management of Calcaneal fractures.

METHODS AND ANALYSIS

This study performed a comprehensive search on PubMed, EMBASE, and Cochrane electronic to retrieve related clinical studies. The studies incorporated in our meta-analysis were identified after doing a preliminarily screening, reading of the full-text articles, and eliminating repeated studies. After quality assessment and data extraction, the standardized mean difference and risk ratio were selected as effect sizes. The data on Böhler angle, Gissane angle, calcaneal height, American Orthopaedic Foot and Ankle Society hindfoot scores, Maryland Foot Evaluation, and rate of wound infection were analyzed using Revman 5.3 software (Cochrane Collaboration).

RESULTS AND CONCLUSIONS

This study did not reveal any significant differences (P < .05) in both Böhler and Gissane angles, calcaneal height, American Orthopaedic Foot and Ankle Society hindfoot scores, Maryland foot evaluation, and rate of wound infection between the 2 groups. Due to the lack of a large sample of comparative studies, the use of bone grafting for the management of calcaneal fractures requires additional substantiation.

Böhler's Angle-Comparison Between the pre- and Postoperative in Displaced Intra-Articular Calcaneal Fractures

Objective  To compare pre- and postoperative variation of radiographic measurements of the Böhler angle (BA) in fractures with two types of deviations: severe and moderate. Methods  Pre- and postoperative BAs in 31 calcaneal fracture radiographs were retrospectively analyzed. A total of 4 patients were female (6.5%) and 26 were male (83.9%), with age ranging from 23 to 72 years old, and a mean age of 44.5 years old. Results  The results show that the postoperative BA was significantly larger than the preoperative BA ( p  = 0.000). At the intraevaluator and overall assessments, the postoperative BA was, on average, 10.6° higher than the preoperative measure. The postoperative angle was, on average, 108% higher than the preoperative angle. In the global assessment, the agreement between evaluators was excellent, both regarding the estimated point value (0.98) and the intraclass correlation (ICC) confidence interval (CI). Conclusion  In the global analysis, the postoperative BAs were, on average, significantly higher than the preoperative measurements. The farther from the normal range (20° to 40°) the preoperative angle is, the greater the difference after the surgery. When the preoperative angle was normal, the postoperative angle was, on average, 1.28 times the preoperative measurement. If the preoperative BA was abnormal, the postoperative angle was, on average, 17.3 times the preoperative measurement. It was demonstrated that more severe fractures present better anatomic results when compared with moderate fractures. The present study also confirms a good interobserver correlation for the BA.

Short-Term Outcomes of Open Reduction and Internal Fixation for Sanders Type III Calcaneal Fractures With and Without Bone Grafts

Calcaneal fractures, often caused by a fall from a height, are the most common injuries encountered by orthopedic surgeons. Currently, open anatomic reduction and internal fixation (ORIF) is considered a valuable treatment of displaced intraarticular fractures of the calcaneus; however, the need for bone grafting in the treatment is still controversial. Therefore, in the present study, we investigated the outcomes of 2 methods (with and without bone grafting) used for the surgical treatment of Sanders type III calcaneal fractures. From January 2013 to September 2015, 57 cases (55 patients) with displaced Sanders type III calcaneal fractures (53 unilateral and 2 bilateral) were enrolled. The patients were divided into 2 groups: group I was treated by ORIF with bone grafting (n = 28) and group II was treated by ORIF without bone grafting (n = 29). The radiologic evaluation included Böhler's angle, Gissane's angle, and the height and width of the calcaneum. In addition, the American Orthopaedic Foot and Ankle Society questionnaires and visual analog scale were completed by the patients. During the follow-up period, no differences were found in the outcome measures (Böhler's angle, p = .447; Gissane's angle, p = .599; calcaneal height, p = .065; calcaneal width p = .077; and American Orthopaedic Foot and Ankle Society questionnaires, p = .282) with or without bone grafting. The only difference between the 2 groups was the occurrence of postoperative pain (p = .024 and p = ≤ .05), which was greater in the patients who had undergone bone grafting. We have provided evidence that bone grafting with internal fixation in the treatment of intraarticular calcaneal fractures failed to improve the restoration of Böhler's angle or Gissane's angle. No statistically significant difference was found in the short-term outcomes between the 2 methods used for the surgical treatment of Sanders type III calcaneal fractures.

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

Induced membrane technique using beta-tricalcium phosphate for reconstruction of femoral and tibial segmental bone loss due to infection: technical tips and preliminary clinical results

PURPOSE

This study aimed to provide preliminary evidence regarding effectiveness of grafting beta-tricalcium phosphate (β-TCP) combined with a cancellous autograft for treating nonunion of long bones in the lower extremity due to infection by evaluating clinical and radiological outcomes.

METHODS

We retrospectively reviewed the clinical and radiological results in seven patients (six men, one woman; median age 39 years) treated by the induced membrane technique for nonunion of the femur or tibia due to infection. In the second stage of the procedure, the bony defect was filled with a combination of autologous cancellous bone and β-TCP, which were mixed in approximately the same proportions. The time interval between the second stage of the procedure and bone healing was investigated. Radiographic characteristics including maximum bone gap and radiographic apparent bone gap were evaluated.

RESULTS

The median follow-up period was 14 months. Bone healing was achieved in a median of six months after the second procedure. The median maximum bone gap and radiographic apparent bone gap were 55 mm and 34 mm, respectively.

DISCUSSION

Use of β-TCP, which has osteoconductive ability, with an autograft provided good clinical and radiological outcomes. The findings of this preliminary study suggest the potential of β-TCP as a useful bone substitute for autografts in the induced membrane technique.

CONCLUSIONS

Our findings suggest that β-TCP may be an effective extender when using the induced membrane technique.

Allografts versus Equine Xenografts in Calcaneal Fracture Repair

Displaced intra-articular calcaneal fractures are difficult to treat. We determined the functional results and complications of using allografts or equine xenografts in treating these fractures. We reviewed patients seen at our center from May 2011 to December 2014 with Sanders type III or IV unilateral calcaneal fractures treated with locking plates and an additional bone allograft or equine xenograft. A minimum of 1 year after surgery, a history of infection and functional outcomes were assessed using the American Orthopaedic Foot and Ankle Society clinical rating system. Changes in the Gissane angle (GA) and Böhler angle were assessed from radiographs. Of the 91 eligible patients, 15 were lost to follow-up, leaving a sample of 76 patients (42 males): 45 received allografts (19 for type III and 26 for type IV fractures) and 31 received xenografts (20 for type III and 11 for type IV fractures). The mean age was about 40 years in both groups. After ≥1 year of follow-up, the proportion of patients in the American Orthopaedic Foot and Ankle Society scoring categories did not differ significantly between the 2 groups (mean ankle score, 86.5 in the allograft group and 85.1 in the xenograft group), and the American Orthopaedic Foot and Ankle Society functional outcomes were good or excellent in 69% and 68%, respectively (p = .986). The groups did not differ in the incidence of superficial or deep infection (p = 1.000). The Böhler angles were significantly decreased in the xenograft group. Xenografts might be preferred for repairing intra-articular calcaneal fractures because they can perform as well as allografts, avoid donor site morbidities, and are more available and less expensive than allografts.

Need for Bone Grafts in the Surgical Treatment of Displaced Intra-Articular Calcaneal Fractures

Controversy is ongoing regarding the use of bone grafts to fill cavities that occur with collapse of the posterior facet in the joint and for repair of the calcaneal height with plating. The present study included 40 patients with 43 displaced intra-articular calcaneal fractures treated with open reduction and internal fixation from March 2009 to November 2013. In the present case-control study, the patients were separated into 2 groups: group A received an allograft (20 patients, 22 calcaneal fractures) and group B did not (20 patients, 21 calcaneal fractures). The calcaneal height and Böhler's angle were compared between the 2 groups. The final outcomes for all patients were evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) ankle hindfoot scale score and compared between the 2 groups. No significant differences were observed between the groups with regard to the basic demographic variables (p > .05). Using Sanders classification, 8 (18%) were type 2, 19 (44%) were type 3, and 16 (37%) were type 4 fractures. The comparisons between the 2 groups showed a loss of Böhler's angle and loss of calcaneal height that was significantly greater in group B (p < .001). No significant differences were observed between the 2 groups in the AOFAS ankle hindfoot scale scores (p > .05). In conclusion, although no differences were found in the clinical results between the 2 groups, more satisfactory radiologic results were obtained in group A, in which bone grafts were used.

There is poor reliability of Böhler's angle and the crucial angle of Gissane in assessing displaced intra-articular calcaneal fractures

BACKGROUND

Two-dimensional measurements are used to describe displaced intra-articular calcaneal fractures (DIACF). Our study evaluates the performance of Böhler's angle (BA) and the crucial angle of Gissane (CAG) among orthopedic surgeons.

METHODS

Thirty-four pre- and post-operative lateral foot radiographs from patients with DIACF were shown to four orthopedic surgeons who measured BA and the CAG. The intra- and inter-observer reliability were calculated using the intra-class correlation coefficient (ICC). Additionally, we calculated frequency of consensus given an allowed discrepancy. We then determined the tolerance limit for each measurement.

RESULTS

The ICC for inter-observer reliability of BA was 0.83 in the first session and 0.77 in the second. The ICC for intra-observer reliability ranged from 0.83 to 0.98. For the CAG, the inter-observer ICC was 0.28 and 0.1 in the two sessions. Intra-observer ICC ranged from 0.16 to 0.67. With an allowed discrepancy of 20°, there was lack of consensus for BA in 37.5% and for the CAG in 59% of measurements on average. The 95% confidence interval for 90% agreement in BA involved a range of 76°. For CAG, the 95% confidence interval of tolerance for 90% agreement was 56°.

CONCLUSIONS

For BA and CAG, there is frequent disagreement among experienced observers, even given a wide tolerance range. We recommend use of caution when applying BA as currently measured in making treatment decisions for DIACF.

LEVEL OF CLINICAL EVIDENCE

Diagnostic, level III.

Posterior Facet Settling and Changes in Bohler's Angle in Operatively and Nonoperatively Treated Calcaneus Fractures

BACKGROUND

Patients with calcaneus fractures often exhibit settling of the posterior facet with a corresponding decrease in Bohler's angle (BA) following either operative or nonoperative treatment. Both injury BA and postoperative BA have been shown to be prognostic for outcomes; however, the demographic and surgeon-specific factors that may contribute to settling have not been critically examined in the literature. The purpose of this study was to identify these causative factors.

METHODS

234 patients with intra-articular calcaneus fractures were analyzed. All patients had preoperative plain radiographs, at least 5 months of orthopedic follow-up, and computed tomography scanning performed. BA was measured on the injury radiographs for all patients. For operatively treated patients, BA was measured on the immediate postoperative radiographs and compared with the last available radiograph. For nonoperatively treated patients, BA was measured on the last available radiograph. All patients were fully weightbearing at the time of final follow-up but not on initial radiographs due to their recent injury. Demographic data including age, gender, energy of injury mechanism, tobacco use, diabetes, osteoporosis, rheumatoid arthritis, and substance/alcohol abuse were retrospectively collected. Fractures were classified using the Essex-Lopresti and Sanders classifications. Time to full weightbearing was documented, as were any reports of noncompliance with weightbearing restrictions. For patients treated operatively, type of fixation (calcaneal-specific perimeter plate, nonperimeter plate, screw fixation), use of locking screws, use of bone graft or graft substitutes, and the number of screws supporting the posterior facet were documented.

RESULTS

There was a statistically significant amount of settling within the operative and nonoperative groups, but there was no statistically significant difference in settling of BA between the groups. The average settling of BA for the operative and nonoperative group was 8 degrees. Age greater than 50 years, diabetes, and alcohol abuse were all statistically significant and independent predictors of BA settling irrespective of treatment.

CONCLUSION

The amount of BA settling between the operative and nonoperative group was not significant and showed an average decrease of 8 degrees in each group. However, the amount of settling that we found, irrespective of treatment, increased with patient age, alcohol abuse, and diabetes.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

The diagnostic accuracy of Böhler's angle in fractures of the calcaneus

BACKGROUND

Böhler's historical tuber-joint angle of the calcaneus has been used since 1931. Surprisingly, there is a paucity of literature on its use.

OBJECTIVES

To confirm the normal range for Böhler's angle and determine the angle with the highest accuracy in the diagnosis of calcaneal fractures.

METHODS

A retrospective cohort study was performed. The study cohort comprised 424 patients spanning a 5-year period from April 2005 to March 2010. Böhler's angle was measured by two independent observers on lateral x-ray study using the digital angle tool from the Picture Archival and Communication System. Data were analyzed using Stata 8 statistical software package.

RESULTS

The mean Böhler's angle in patients without calcaneal fracture was 29.4°. In this group there was no difference in Böhler's angle between male and female patients, left and right feet, or across age. In those patients with calcaneal fractures, a Böhler's angle below 25° was moderately predictive of calcaneal fracture (sensitivity = 100%, specificity = 82%), an angle below 23° was highly predictive of calcaneal fracture (sensitivity = 100%, specificity = 89%), and an angle below 21° was strongly suggestive of calcaneal fracture (sensitivity = 99%, specificity = 99%). A Böhler's angle of ≤ 20° had the highest diagnostic accuracy.

CONCLUSION

A Böhler's angle of 20° or less is highly accurate in determining the presence or absence of calcaneal fracture. Böhler's angle serves as a useful screening tool in fracture diagnosis.

Comparison of tricalcium phosphate cement and cancellous autograft as bone void filler in acetabular fractures with marginal impaction

OBJECTIVE

To compare clinical and radiological outcome between acetabular fractures with marginal impaction that were treated with either cancellous bone graft (CBG) or tricalcium phosphate cement (TPC) as bone void filler.

DESIGN

Retrospective study.

PATIENTS

Forty-three patients with acetabular fractures with marginal impaction.

INTERVENTION

Eighteen patients received cancellous bone graft and 25 patients received tricalcium phosphate cement as bone void filler.

MAIN OUTCOME MEASUREMENT

Clinical outcome was assessed using the Merle d'Aubigne score and Short-form-36. Radiographs were evaluated for postoperative reduction, arthritis grade and development of heterotopic ossification.

RESULTS

Forty-three patients met the inclusion criteria. There was no significant difference in the demographics, laterality, fracture type, associated injuries, surgical approach and postoperative quality of reduction between the groups. At final follow-up, a significantly higher number of patients in the cancellous bone graft group exhibited signs of moderate to severe post-traumatic arthritis (CBG: 6 (33%) vs. TPC: 4 (20%), p=0.007) and required a total hip arthroplasty (CBG: 4 (22.2%) vs. TPC: 1 (5%), p=0.08). There was no significant difference between the two groups in the SF-36 score and the modified Merle d'Aubigne score.

CONCLUSION

Patients with acetabular fractures with marginal impaction treated with tricalcium phosphate cement exhibit a significantly lower incidence of post-traumatic arthritis when compared to patients treated with cancellous bone graft.

LEVEL OF EVIDENCE

III.

Surgical treatment of displaced intra-articular calcaneal fractures: is bone grafting necessary?

Background

The aim of this retrospective study was to determine the need for bone grafting in the surgical treatment of displaced intra-articular calcaneal fractures. We reviewed 390 cases of displaced intra-articular calcaneal fractures treated with plate osteosynthesis with or without autologous iliac bone grafting, and compared outcomes and complications related to fracture stabilization.

Materials and methods

Three hundred ninety patients with displaced intra-articular calcaneal fractures that were treated with plate osteosynthesis from December 2002 to December 2010 were reviewed. Two hundred two patients (group A) were treated by osteosynthesis with autologous bone grafting, and 188 patients (group B) were treated by osteosynthesis without bone grafting. One hundred eighty-one patients with an AO type 73-C1 fracture (Sanders type II), 182 patients with an AO type 73-C2 fracture (Sanders type III), and 27 patients with an AO type 73-C3 fracture (Sanders type IV) were included in this study. Bohler’s angle, the crucial angle of Gissane, and calcaneal height in the immediate postoperative period and at the 2-year follow-up were compared. Any change in the subtalar joint status was documented and analyzed. The final outcomes of all patients were evaluated by the AOFAS Ankle–Hindfoot Scale and compared in both groups.

Results

The mean full weight-bearing time in group A (with bone grafting) was significantly lower (median 6.2 months, range 2.8–9.2 months) than that in group B (without bone grafting; median 9.8 months, range 6.8–12.2 months). The immediate-postoperative Bohler’s angle and that at the 2-year follow-up were significantly higher in group A. The loss of Bohler’s angle after 2 years was significantly lower in group A (mean 3.5°; 95 % CI 0.8°–6.2°) than in group B (mean 6.2°; 95 % CI 1.0°–11.2°). The average change in the crucial angle and the average change in calcaneal height were not statistically significant for either group. The infection rate in the bone grafting group was higher, though statistically insignificantly so, than in the nongrafting group (8.3 vs. 6.3 %). No significant difference was found between the groups in terms of the rates of good reduction, postoperative osteoarthritis, and subtalar fusion. Regarding the efficacy outcomes, the mean AOFAS score was lower (mean 76.4 points; 95 % CI 65.8–82.9 points) in group A than in group B (mean, 81.6 points; 95 % CI, 72.3–88.8 points), but this difference was not significant (p > 0.05).

Conclusions

Bohler’s angle showed improved restoration and the patients returned to full weight-bearing earlier when bone grafting was used in the treatment of intra-articular calcaneal fracture. However, the functional outcomes and complication rates of both groups were similar.

Recommendations and considerations for the use of biologics in orthopedic surgery

Reconstruction of extensive bone defects remains technically challenging and has considerable medical and financial impact on our society. Surgical procedures often require a bone/substitute graft to enhance and accelerate bone repair. Bone autografts are associated with morbidity related to bone harvesting and are limited in quantity. Alternatively, bone allografts expose the patient to the risk of transmission of infectious disease. Synthetic bone graft substitutes, such as calcium sulfates, hydroxyapatite, tricalcium phosphate, and combinations, circumvent some of the disadvantages of auto- and allografts, but have limited indications. Biomedical research has made possible the stimulation of the body's own healing mechanisms, either by delivering exogenous growth factors locally, or by stimulating their local production by gene transfer. Among all known factors having osteoinductive properties, only two bone morphogenetic proteins (for specific indications) and demineralized bone matrix have been approved for clinical use. In addition, ongoing research is exploring the efficacy of cell therapy and tissue engineering. The present report examines the composition, biological properties, indications, clinical experience and regulations of several of the biotherapeutics employed for bone reconstruction.

The fate of Böhler's angle in conservatively-treated displaced intra-articular calcaneal fractures

PURPOSE

Although the predictive value of Böhler's angle on outcome remains subject of debate, the initial angle at the time of trauma still guides treatment. Changes in Böhler's angle during follow-up are frequently reported following surgical treatment of displaced intra-articular calcaneal fractures (DIACF). The aim of the present study was to determine the changes in Böhler's angle as a measure of secondary fracture displacement following conservative management of DIACF.

METHODS

Thirty-eight patients with a total of 44 displaced intra-articular calcaneal fractures treated conservatively with a minimum of two lateral radiographs during follow-up were analysed. Böhler's angle at different follow-up times was measured by three observers. The change in angle was compared with the angle at trauma, and influence of trauma mechanism and common calcaneal fracture classifications were determined.

RESULTS

The results showed a significant decline over time of the Böhler's angle in conservatively-treated patients of more than 11° on average at a mean follow-up of 29.2 weeks. This decrease was not related to gender, the initial angle, or the Essex-Lopresti or Sanders classification. A statistically significantly higher decrease was detected in high energetic trauma compared with low energetic trauma.

CONCLUSION

The conservative treatment of displaced intra-articular calcaneal fractures is still a viable option, yet a significant secondary displacement in time should be taken into account, as reflected in a decrease of Böhler's angle of 11° up to one year following trauma.

Treatment of displaced intraarticular calcaneal fractures with or without bone grafts: A systematic review of the literature

BACKGROUND

The necessity of bone grafts in the treatment of intraarticular calcaneal fractures continues to be one of the most debated topics in foot and ankle surgery. The purpose of this study was to determine whether there are sufficient objective cumulative data in the literature to compare the two methods and if the bone graft was needed in surgical treatment of intraarticular calcaneal fractures.

MATERIALS AND METHODS

A comprehensive search of all relevant articles from 1990 to 2010 was conducted. Two reviewers evaluated each study to determine its suitability for inclusion and collected the data of interest. Meta-analytic pooling of group results across studies was performed for the two treatment methods.

RESULTS

The systematic review identified 32 primary studies with 1281 fractures, which contained 4 comparative studies, 13 with bone grafts, and 15 without bone grafts in treatment methods. The infection rate in bone graft group was higher through statistically insignificant than in non-graft group (8.3% vs. 6.3%) No significant difference was found between good reduction rate, postoperative osteoarthritis rate, and subtalar fusion rate. The average full weight-bearing time in bone graft group was significantly lower (5.4 months) than in non-graft group (10.5 months). The mean postoperative Böhler's angle was significantly higher in bone graft group (lose due to collapse was significancy less). For the efficacy outcomes, the bone graft group had a lower American Orthopaedic Foot and Ankle Society Score (AOFAS) (71.4 points vs. 80.5 points) but a higher Creighton score (89.9 points vs. 81.0 points) compared with non-graft group. Pooled mean results showed 35% of the patients in bone graft group had an excellent result, 40% had a good result, 21% had a fair result, and 4% had a poor result. In the non-graft group, the corresponding values were 34, 42, 14, and 10%, respectively.

CONCLUSIONS

The operative treatment of intraarticular calcaneal fractures with bone grafts could restore the Böhler's angle better and the patients could return to full weight bearing earlier. However, the functional and efficacy outcomes appear to be similar between the two treatment groups. There were more joint depression and comminuted fractures in the bone graft group, and the mean followup time was shorter. Large sample comparative studies are still needed.

Controversies in calcaneus fracture management: a systematic review of the literature

Despite the fact that the calcaneus is the commonest tarsal bone fractured, many controversies exist in the literature regarding the management options. This stems from the fact that the understanding of the fracture pattern has evolved only recently, surgical approaches have lately been standardized, surgical timing has become more clear, and newer implants are regularly being introduced. Despite the significant advances, complications and controversies related to this common fracture abound. The present paper looks at all aspects of modern management options of calcaneus fractures and tries to review the literature with regard to the controversial issues that still persist.

Interobserver reliability and intraobserver reproducibility of three radiological classification systems for intra-articular calcaneal fractures

BACKGROUND

The management of intra-articular calcaneal fractures is difficult. One aspect for successful management is the use of a reliable and reproducible fracture classification system (FCS). The purpose of this study was to evaluate the interobserver reliability and intraobserver reproducibility of Letournel, Sanders, and Zwipp classification systems on CT scan and the Bohler's angle measurement on plain X-ray. Furthermore, we studied if the addition of a CT scan to the plain X-ray influenced the evaluation of fracture extension to the calcaneocuboid joint.

METHODS

The CT scan and plain X-ray images of 51 intra-articular calcaneal fractures were evaluated two times by three observers (two radiologists and one orthopedic surgeon) within a 5-month interval. The interobserver reliability was measured using the Fleiss kappa while the intraobserver reproducibility was measured using the Cohen's kappa.

RESULTS

The mean kappa values for the interobserver reliability and intraobserver reproducibility of the Sanders classification were 0.25 and 0.39, respectively, of Zwipp classification were 0.24 and 0.16, respectively, while those of the Letournel classification were 0.50 and 0.42, respectively. For the Böhler's angle, the mean kappa values for the interobserver reliability and intraobserver reproducibility were 0.34 and 0.32, respectively. The addition of CT scan images to plain X-ray found a higher incidence of calcaneocuboid joint involvement.

CONCLUSION

Clinicians should be aware of the limitation regarding the interobserver reliability and intraobserver reproducibility of the Letournel, Sanders and Zwipp classification systems for calcaneal fractures. Future studies should attempt to improve the present classification systems.

Bone repair using a hybrid scaffold of self-assembling peptide PuraMatrix and polyetheretherketone cage in rats

Self-assembling peptide scaffold (SAPS) is well known to have very good bone conduction properties. However, the intensity of SAPS is too weak to actually use it for a clinical bone regeneration. Therefore, we have produced a hybrid scaffold system that involves fabricating a cage from polyetheretherketone (PEEK) that has high intensity, filling the interior of this cage with SAPS, and then transplanted this hybrid scaffold to bone defects in rat femurs. After 28 days, soft X-ray radiographs and histological assessment revealed that good new bone formation was clearly observed in the defects transplanted the PEEK cage with SAPS, but not in the PEEK cage only. The PEEK cage maintained a form and osteoconduction ability of internal SAPS, and SAPS promoted bone formation inside the PEEK; therefore, each was in charge of intensity and bone regeneration separately. The present study suggests that hybrid scaffolds made from PEEK cages and SAPS can be useful tools for the regeneration of load-bearing bones, based on the idea that it should be possible to develop ideal bone filler materials by combining the strength of artificial bone with the bone regeneration and bone conduction properties of SAPS.

Calcium phosphates: what is the evidence?

A number of different calcium phosphate compounds such as calcium phosphate cements and solid beta-tricalcium phosphate products have been introduced during the last decade. The chemical composition mimics the mineral phase of bone and as a result of this likeness, the materials seem to be remodeled as for normal bone through a cell-mediated process that involves osteoclastic activity. This is a major difference when compared with, for instance, calcium sulphate compounds that after implantation dissolve irrespective of the new bone formation rate. Calcium phosphates are highly biocompatible and in addition, they act as synthetic osteoconductive scaffolds after implantation in bone. When placed adjacent to bone, osteoid is formed directly on the surface of the calcium phosphate with no soft tissue interposed. Remodeling is slow and incomplete, but by adding more and larger pores, like in ultraporous beta-tricalcium phosphate, complete or nearly complete resorption can be achieved. The indications explored so far include filling of metaphyseal fracture voids or bone cysts, a volume expander in conjunction with inductive products, and as a carrier for various growth factors and antibiotics. Calcium phosphate compounds such as calcium phosphate cement and beta-tricalcium phosphate will most certainly be part of the future armamentarium when dealing with fracture treatment. It is reasonable to believe that we have so far only seen the beginning when it comes to clinical applications.