Outcomes of intra-articular calcaneal fractures: surgical treatment of 114 consecutive cases at a maximum care trauma center

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.

Analysis of risk factors associated with incision complications in modified "L" approach for calcaneal fracture

OBJECTIVE

This study aimed to identify risk factors associated with incision complications following the modified "L" approach for calcaneal fractures.

METHODS

Data from 100 patients treated with the modified "L" approach for calcaneal fractures between January 2018 and December 2021 were analyzed. These included 52 cases in the poorly healing group and 48 in the well-healing group. Variables such as patient age, sex, body mass index, fracture type (Sanders classification), smoking history, alcohol consumption, diabetes status, timing of surgery, tourniquet use, bone grafting, suture method, and postoperative incision care were evaluated. A nomogram was developed using R software to predict the risk of incision complications, validated through the area under the ROC curve, C-index, and decision curve analysis.

RESULTS

Both univariate and multivariate regression analyses identified fracture type, smoking history, diabetes, timing of surgery, and duration of tourniquet application as significant predictors of incision complications. These factors were incorporated into a clinical predictive nomogram. The nomogram's calibration curves demonstrated high accuracy, both internally and externally. The unadjusted concordance indes (C-index) was 0.793 [95% confidence interval (CI), 0.825-0.995], and the area under the curve for the nomogram was 0.7875882. Decision curve analysis confirmed the clinical applicability of the model at a threshold probability of 20-60%.

CONCLUSION

We have developed a reliable clinical nomogram to predict the risk factors for incision complications in the modified "L" approach for calcaneal fractures, enhancing decision-making in clinical settings.

Clinical outcomes following treatment of deep surgical site infection after fixation of calcaneal fractures: A retrospective case-control study

INTRODUCTION

Deep surgical site infection (SSI) may be a complication of open reduction and internal fixation (ORIF) of calcaneal fractures. This study aimed to describe the characteristics of patients with deep SSI following ORIF of calcaneal fractures via extensile lateral approach (ELA). We compared clinical outcomes of these patients, with a minimum follow-up of one year after successful treatment of deep SSI with a matched control group.

METHODS

In this retrospective case-control study, demographic data, fracture characteristics, bacterial pathogens, medical treatments and surgical approaches were collected, also the outcome was evaluated by the visual analog scale (VAS) for pain, foot function index (FFI) and AOFAS ankle-hindfoot score. The differences in Böhler and Gissane's angles between infected and contralateral feet were measured. By matching a control group of uninfected cases, clinical outcomes were compared between 2 groups using the Mann-Whitney U test.

RESULTS

Among 331 calcaneus fractures in 308 patients (mean age, 38.0 ± 13.1; male/female ratio, 5.5), 21 had deep SSI (6.3 %). There were 16 (76.2 %) males and 5 (23.8 %) females with a mean age of 35.1 ± 11.7 years. Thirteen (61.9 %) patients had unilateral fractures. The most common Sanders Type was found to be type II. The most frequent type of detected microorganisms was Staphylococcus species. Intravenous antibiotic therapy, mostly clindamycin, imipenem and vancomycin, based on the microbiological results, was prescribed with a mean±SD duration of 28.1 ± 16.5 days. The mean number of surgical debridements was 1.8 ± 1.3. Implants needed to be removed in 16 (76.2 %) cases. Antibiotic-impregnated bone cement was applied in three (14.3 %) cases. The clinical outcomes of 15 cases (follow up, 35.5 ± 13.8; range, 12.6-64.5 months) were 4.1 ± 2.0, 16.7 ± 12.3 and 77.5 ± 20.8 for VAS for pain, FFI % and AOFAS ankle-hindfoot score, respectively. Comparing with the control group (VAS for pain, 2.3 ± 2.7; FFI %, 12.2 ± 16.6, and AOFAS, 84.6 ± 18.0), only VAS pain was statistically lower in this group (p-value: 0.012). The differences in Böhler and Gissane's angles between both feet of infected cases were - 14.3 ± 17.9 and - 7.7 ± 22.5 (worse in the infected side), respectively.

CONCLUSION

Proper on-time approaches to deep infection following ORIF of calcaneal fractures may lead to acceptable clinical and functional outcomes. Sometimes aggressive approaches with intravenous antibiotic therapy, multiple sessions of surgical debridement, removal of implants and antibiotic impregnated cement are necessary to eradicate deep infection.

LEVEL OF EVIDENCE

Level III.

Calcaneus Fracture and Posterior Arthroscopic Primary Subtalar Arthrodesis (C-PASTA)

Complex intra-articular calcaneal fractures often resulted in secondary pain and deformity, requiring subsequent subtalar arthrodesis^1-3. The literature suggests that primary subtalar arthrodesis in the acute period has good functional results^2,3. The literature also demonstrates that posterior arthroscopic subtalar arthrodesis for chronic arthritis has favorable results⁵. Thus, we propose an approach to treating these difficult intra-articular calcaneal fractures that utilizes a posterior arthroscopic primary subtalar arthrodesis technique-aptly named Calcaneus Fracture and Posterior Arthroscopic Primary Subtalar Arthrodesis (C-PASTA).

Description

The procedure begins with the patient in the prone position. The subtalar joint is visualized with a 1.9-mm flexible camera through a standard posterior arthroscopic approach. With the help of the C-arm, position in the subtalar joint space is confirmed. The joint space is debrided with use of a 4-0 shaver and then prepared for arthrodesis arthroscopically with use of an osteotome and a burr. Next, we inject allograft demineralized matrix-based bone putty under direct arthroscopic visualization to fill residual gaps or defects. The arthrodesis is performed under fluoroscopic guidance with use of 2 guidewires followed by 2 to 3 titanium compression screws. The first screw is inserted along the posteromedial calcaneus and into the talar dome medially. The second is placed laterally into the head-neck junction of the talus. The third screw is placed distal to proximal from the plantar anterior process to the talar head. Finally, images are obtained in multiple views to ensure proper screw placement, and the screws are tightened sequentially to ensure equal compression across the joint.

Alternatives

Nonoperative treatment of calcaneal fractures includes cast immobilization with non-weight-bearing, although this treatment is typically reserved for nondisplaced, small extra-articular fractures⁶. Operative treatment of calcaneal fractures includes open reduction and internal fixation, which is traditionally performed via a sinus tarsi approach or extensile lateral approach. Primary subtalar arthrodesis has been utilized primarily for Sanders type-IV fractures⁶.

Rationale

Displaced intra-articular calcaneal fractures are associated with alarmingly high rates of posttraumatic arthritis (30% to 70% within 1 year of injury), and surgical outcomes are inversely proportional to the severity of the fracture pattern, with Sanders III and IV having the worst outcomes¹. Treating these most severe fracture patterns with primary open subtalar arthrodesis has shown favorable results in terms of union rates, pain scores, and functional outcomes throughout the literature^2,3. However, some authors have reported rates of revision as high as 60%⁴. Thus, the PASTA procedure has been established, resulting in significantly better time to union, return to work, activities of daily living, and sports activities compared with open techniques⁵. Thus, given the favorable results of primary open subtalar arthrodesis and the proven results with use of an arthroscopic technique in the non-acute setting, we propose that C-PASTA can serve as an alternative treatment option in the acute setting for patients with Sanders type-III and IV calcaneal fractures.

Expected Outcomes

We expect the outcomes of this procedure to mirror those found throughout the literature, which shows favorable results for open primary subtalar arthrodesis^1-3. With use of an arthroscopic approach, we expect better time to union, return to work, activities of daily living, and sports activities than if the procedure were performed in an open fashion⁵. In addition, minimizing soft-tissue damage through an arthroscopic approach may decrease the risk of infection and stimulate postoperative healing, perhaps accounting for the more favorable postoperative recovery period compared with an open procedure.

Important Tips

In the arthroscopic approach to the subtalar joint, identify the flexor hallucis longus, making sure to stay lateral to that tendon to remain in the "safe zone."Utilizing the TRIMANO device (Arthrex) to distract the ankle longitudinally in addition to a solid bump placed on the anterior aspect of the ankle allows for optimal subtalar joint visualization.Fish-scaling with an osteotome followed by bone grafting allows for a good fill between cancellous fragments to stimulate an optimal environment for fusion.Divergent screws should be placed and tightened sequentially to ensure equal compression across the joint.

Abbreviations and Acronyms

ADL's = activities of daily livingCT = computed tomographySCD = sequential compression deviceAP = anteroposteriorDVT = deep vein thrombosisBID = twice dailyVit = vitamin.

Percutaneous subtalar joint screw fixation of comminuted calcaneal fractures: a salvage procedure

INTRODUCTION

Malunited comminuted calcaneal fractures result in poor function due subtalar joint arthritis and altered biomechanics. We aimed to assess whether percutaneous subtalar joint screws after fracture reduction provide good outcomes for these difficult injuries.

METHODS

We retrospectively analysed 15 comminuted calcaneal fractures (in 14 patients) treated with percutaneous subtalar screw fixation. All patients had a minimum of 12 months' follow-up. Six patients had open injuries. On the preoperative and the latest postoperative radiograph, Bohlers angle, Gissane angle, calcaneal inclination, width and length, absolute foot height, and posterior facet height were measured. Preoperative computed tomography scans were used to classify the fractures by Sanders classification. Clinical outcome scores were recorded postoperatively.

RESULTS

Mean age was 34.2 ± 14.2 years. Minimum follow-up was 12 months (mean 17.2 ± 4.4 months). Nine patients had a Sanders 4, 3 had a Sanders 3AB, 2 had a Sanders 3BC, and 1 had a Sanders 3AC fracture. Eighty percent of patients had their angle of Gissane, absolute foot height, calcaneal length and inclination restored by this technique. Bohlers angle was restored back into the normal range in 54% of patients. Mean postoperative AOFAS score was 74 ± 11. AOFAS scores positively correlated with postoperative Bohlers angle (Pearson's correlation coefficient 0.85; p = 0.004). One patient (7%) had a wound breakdown postoperatively and three patients (20%) had heel pain from the screws, which improved after removal.

CONCLUSION

Percutaneous subtalar screws offer a reliable option to restore calcaneal anatomy in comminuted calcaneal fractures, with low complication rates. Over 80% of patients had their angle of Gissane, calcaneal length and inclination restored, and over 50% of patients had all radiological parameters restored by this technique. It offers the benefits of percutaneous reduction and fixation and this procedure may be considered an effective first stage prior to definitive subtalar fusion. Further work is needed to review the longer-term outcomes and the conversion rate to arthrodesis.

LEVEL OF EVIDENCE

IV (case series), Therapeutic.

Calcaneal Fractures-Which Approach for Which Fracture?

Treatment of calcaneal fractures has to be tailored to the individual pathoanatomy. If operative treatment is chosen, anatomic reconstruction of the calcaneal shape and joint surfaces is mandatory. For most of the displaced, intraarticular fractures, this can be achieved by less invasive reduction and fixation via a sinus tarsi approach, which may be extended along the "lateral utility" line for calcaneocuboid joint involvement or calcaneal fracture-dislocations. Purely percutaneous fixation is the treatment of choice for displaced extraarticular fractures and simple intraarticular fractures with adequate control of joint reduction. Specific approaches are used for rare calcaneal fracture variants.