A biomechanical evaluation to optimize the configuration of a hinged external fixator for the primary treatment of severely displaced intraarticular calcaneus fractures with soft tissue damage

A simple modified technique for screw fixation of displaced intra-articular calcaneus fracture through a sinus tarsi approach: a comparison with plate fixation

BACKGROUND

Plates and screws are frequently used for the fixation of displaced intra-articular calcaneus fracture (DIACF). In this study, we compared the outcomes of a modified screw fixation technique with plate fixation via a sinus tarsi approach (STA).

METHODS

A series of 187 DIACF patients who were treated via an STA using a plate fixation (n = 81) or a screw fixation (n = 106) were included. Screw fixation was done with two 2.7 mm screws and two 6.5 mm cannulated screws. Outcomes were evaluated radiographically and clinically. Clinical evaluations included pain assessment by Visual Analogue Scale (VAS) and functional assessment by the American Orthopaedic Foot and Ankle Society (AOFAS) questionnaire and Foot Function Index (FFI).

RESULTS

The mean final VAS was smaller in the screw group (P = 0.01). The mean AOFAS and FFI scores were not significantly different between the two groups (P = 0.17 and P = 0. 19, respectively). The mean improvement of Bohler's angle, but not the Gissane's angle, was significantly greater in the screw group (P = 0.014 and P = 0.09, respectively). The mean improvement of calcaneal length and height were not significantly different between the two groups (P = 0.78 and P = 0.22, respectively). The hardware removal rate was 14.8% in the plate group and 3.8% in the screw group (P = 0.007).

CONCLUSION

The modified screw fixation method provides lower pain, better radiographic outcome, and lower rate of hardware removal compared to plate fixation in the treatment of DIACF.

Percutaneous fixation of displaced intraarticular fractures of the calcaneus. A retrospective case series study and a review of the literature

PURPOSE

To evaluate the outcome of displaced intraarticular calcaneal fractures (DIACFs) of a case series of patients who were treated with a percutaneous fixation technique.

MATERIALS AND METHODS

Eight patients were operated for DIACFs and they were evaluated for the outcome and complications in a mean follow up of 9 months (range: 6 - 12 months). At the last follow up the AOFAS score, the Boehlers' angle and the presence of any complication were noted. The time from injury to surgery was also reported. The correlation of the AOFAS score and the development of post traumatic subtalar arthritis to the type of fracture, to the post operative Boehler's angle and to the time from injury to surgery were investigated.

RESULTS

The overall mean AOFAS (Americal Orthopaedic Foot and Ankle Society) score was 84,625 (Range: 73 - 96). The mean AOFAS score of type II and type III fractures was 87,667 and 75,500 respectively. The mean AOFAS score for fractures with a postoperative Boehler's angle of less than 10° and more or equal to 10° was 76,750 and 92,500 respectively. This difference was found to be statistically significant. The mean AOFAS score for fractures who were treated less or equal to six days and more than six days post injury was 91,250 and 78 respectively. Two out of four patients with a post operative Boehler's angle less than 10° developed post traumatic subtalar arthritis. No patient out of four for whom a Boehler's angle of more than 10° has been achieved, developed subtalar arthritis. No infection occurred in any of the patients.

CONCLUSION

Percutaneous fixation is a safe and effective way of treating DIACFs. The outcome is directly related to the quality of reduction, which is significantly dependent to the timing of surgery. The earlier the fracture is operated the better the reduction by closed means is.

Comparison of vacuum sealing drainage and conventional drainage for postoperative drainage in closed calcaneal fracture: A randomized controlled trial

BACKGROUND

The objective of this study was to compare the outcomes of vacuum sealing drainage (VSD) and conventional drainage after surgery in the treatment of closed calcaneal fracture. We hypothesize that VSD is superior to conventional drainage in reducing volume of drainage, time of wound drying, time of skin fold, time of wound healing, VAS at day 3 postoperatively, wound complications and increasing wound healing grade.

METHODS

120 patients with closed calcaneal fractures from January 2016 to December 2018 were enrolled in our study. They were divided randomly into VSD group (n = 60) and conventional (n = 60). The volume of drainage, duration of drainage, time of wound drying, time of skin fold, time of wound healing and VAS at day 3 postoperatively were recorded. Furthermore, the wound complications of the two groups were also evaluated. Besides, wound healing grade was used to assess the degree of wound healing. The functional outcome American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot scores and visual analog scale (VAS) pain scores was also evaluated.

RESULTS

A total of 10 patients were lost to follow-up for various reasons, VSD group remained 55 cases while conventional group remained 53 cases. Our results showed that VSD group exhibited significantly more volume of drainage (P< 0.0001), longer duration of drainage (P< 0.0001), shorter time of wound drying (P = 0.0086), shorter time of skin fold (P = 0.0158), shorter time of wound healing (P = 0.0240) and lower VAS at day 3 postoperatively (P = 0.0019) compared with conventional group. Moreover, VSD group was demonstrated to have significantly lower wound complications (P = 0.025) and higher rate grade A of wound healing (P = 0.031). However, no significant difference was noted in time of fracture union (P = 0.754), VAS (P = 0.407) and AOFAS score (P = 0.512) at final follow-up between the two groups.

CONCLUSIONS

Our hypothesis was confirmed that VSD was superior in terms of some aspects than conventional drainage. Therefore, VSD is a safe and effective postoperative wound drainage method in the treatment of closed calcaneal fracture. However, more and higher evidence needs to be carried to demonstrate the results.

An engineering review of external fixators

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Mechanical stability plays a key role in the effectiveness of external fixators.

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Strength and stiffness are the main factors which contributes towards stability.

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Modified configurations of linear, circular and hybrid fixators are investigated.

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Light weight composite materials are gradually replacing traditional metallic alloys.

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Existing research gaps in further optimizing external fixators are identified.

External Fixators are a common technique used to treat a variety of issues related to bones, predominantly due to its non-intrusive nature and versatility in terms of form and materials. While it is mainly used to treat open fractures, its other uses include limb lengthening, deformity correction, bone grafting, compression of non-unions and stabilization of dislocations. Its earliest use dates as far back as 400 BCE and has undergone significant improvements, focusing on both customization and optimization. These two aspects highlight the significance of complementing the orthopaedic requirements with engineering knowledge and its applications. Hence, this review paper aims to conduct an examination of recent developments of external fixators with a special focus on its structure, the usage of materials and biomechanical investigations using experimental and numerical techniques. The paper presents the existing level of engineering knowledge with regards to these aspects and identifies research gaps, which can improve the quality of the commonly used external fixators.

Could percutaneous fixation with crossed Schanz pins be an alternative to open reduction in the treatment of intra-articular calcaneal fractures?

PURPOSE

Despite modern operative techniques and a considerable number of studies in the literature, the best treatment for calcaneal fractures remains an enigma for orthopaedic surgeons. The purpose of the study was to compare clinical and radiographic outcomes between anatomic calcaneal plate (ACP) fixation and crossed Schanz pin (CSP) fixation in the treatment of Sanders type II and III displaced intra-articular calcaneus fractures (DICFs).

METHODS

Consecutive 65 patients (49 males, 16 females) who underwent surgery for DCIFs between January 2009 and February 2013 were retrospectively evaluated. The patients were divided into two groups as ACP and CSP according to the operative technique. The groups were compared in terms of demographic features, injury mechanism, operation time, fluoroscopy exposure, complications, full weight-bearing time, functional, and radiological outcomes.

RESULTS

VAS-rest score did not differ significantly between the groups while the VAS-activity score was significantly higher in the CSP group (p = 0.001 and p = 0.645, respectively). Foot Function Index (FFI) was significantly lower, Maryland Foot Score (MFS) and the American Orthopaedic Foot and Ankle Society-hindfoot score (AOFAS) were significantly higher in the ACP group (p = 0.047, p = 0.016, and p < 0.001, respectively). While no difference was observed between the preoperative and the early post-operative (1st day) Böhler angle and Gissane angle, both were significantly higher in the ACP group at the post-operative last control (p < 0.001 and p < 0.001, respectively).

CONCLUSION

Although crossed Schanz pin fixation shortens the operation time in displaced intra-articular calcaneus fractures compared to anatomic calcaneal plate, increased fluoroscopy exposure rates and low functional and radiological outcomes are disadvantageous of crossed Schanz pin. Anatomic calcaneal plate is still a better technique for preserving the alignment and elevating the displaced intra-articular segment for good to excellent mid-term results.

Clinical application of the sinus tarsi approach in the treatment of intra-articular calcaneal fracture

To observe the clinical outcome of the sinus tarsi approach in the operative treatment of intra-articular calcaneal fractures.Forty-nine intra-articular calcaneal fractures in 45 patients were managed surgically with sinus tarsi approach. The anatomical plate and compression bolts were applied in 14 feet. The anatomical plate and screws were applied in 35 feet. Maryland foot score system was used to evaluate the function of the hindfoot at the followup.The reduction of the posterior facet was graded as nearly anatomical (less than 2 mm articular displacement) in 46 feet (93.9%). The width, height, and Böhler angle were significantly improved in all patients (P < .01). After a mean follow-up period of 18.7 months (14.5-29 months), the Maryland foot scores were: 34 feet scored 90-100 points (excellent), 6 feet scored 80-90 points (good), 6 feet scored 70-80 points (fair), and 3 feet scored 60-70 points (poor). Incision-edge necrosis occurred in 2 cases. One case suffered from incomplete medial plantar nerve injury. One case suffered from heel pad branch of the tibial nerve injury. Six cases suffered from sural nerve injury, and 4 cases sustained a lateral wound dehiscence due to a hematoma. No case suffered from lateral impingement syndrome. Up to now, no patient had to accept subtalar arthrodesis.Sinus tarsi approach provides good exposure to the subtalar joint. Open reduction and internal fixation of calcaneus fractures through a sinus tarsi approach allows adequate reduction with low risk of wound-healing complications.

Comparison of the Conventional Surgery and the Surgery Assisted by 3d Printing Technology in the Treatment of Calcaneal Fractures

PURPOSE

This study was aimed to compare conventional surgery and surgery assisted by 3D printing technology in the treatment of calcaneal fractures. In addition, we also investigated the effect of 3D printing technology on the communication between doctors and patients.

METHODS

we enrolled 75 patients with calcaneal fracture from April 2014 to August 2016. They were divided randomly into two groups: 35 cases of 3D printing group, 40 cases of conventional group. The individual models were used to simulate the surgical procedures and carry out the surgery according to plan in 3D printing group. Operation duration, blood loss volume during the surgery, number of intraoperative fluoroscopy and fracture union time were recorded. The radiographic outcomes Böhler angle, Gissane angle, calcaneal width and calcaneal height and final functional outcomes including VAS and AOFAS score as well as the complications were also evaluated. Besides, we made a simple questionnaire to verify the effectiveness of the 3D-printed model for both doctors and patients.

RESULTS

The operation duration, blood loss volume and number of intraoperative fluoroscopy for 3D printing group was 71.4 ± 6.8 minutes, 226.1 ± 22.6 ml and 5.6 ± 1.9 times, and for conventional group was 91.3 ± 11.2 minutes, 288.7 ± 34.8 ml and 8.6 ± 2.7 times respectively. There was statistically significant difference between the conventional group and 3D printing group (p < 0.05). Additionally, 3D printing group achieved significantly better radiographic results than conventional group both postoperatively and at the final follow-up (p < 0.05). However, No significant difference was noted in the final functional outcomes between the two groups. As for complications, there was no significant difference between the two groups. Furthermore, the questionnaire showed that both doctors and patients exhibited high scores of overall satisfaction with the use of a 3D printing model.

CONCLUSION

This study suggested the clinical feasibility of 3D printing technology in treatment of calcaneal fractures.

Comparative study on three surgical techniques for intra-articular calcaneal fractures: open reduction with internal fixation using a plate, external fixation and minimally invasive surgery

Objective

To evaluate, compare and identify the surgical technique with best results for treating intra-articular calcaneal fractures, taking into account postoperative outcomes, complications and scoring in the Aofas questionnaire.

Methods

This was a retrospective study on 54 patients with fractures of the calcaneus who underwent surgery between 2002 and 2012 by means of the following techniques: (1) open reduction with extended L-shaped lateral incision and fixation with double-H plate of 3.5 mm; (2) open reduction with minimal incision lateral approach and percutaneous fixation with wires and screws; and (3) open reduction with minimal incision lateral approach and fixation with adjustable monoplanar external fixator.

Results

Patients treated using a lateral approach, with fixation using a plate had a mean Aofas score of 76 points; those treated through a minimal incision lateral approach with screw and wire fixation had a mean score of 71 points; and those treated through a minimal incision lateral approach with an external fixator had a mean score of 75 points. The three surgical techniques were shown to be effective for treating intra-articular calcaneal fractures, without any evidence that any of the techniques being superior.

Conclusion

Intra-articular calcaneal fractures are complex and their treatment should be individualized based on patient characteristics, type of fracture and the surgeon's experience with the surgical technique chosen.

Surgical treatment of intra-articular calcaneal fractures: description of a technique using an adjustable uniplanar external fixator

Several surgical techniques are available for the treatment of intra-articular calcaneal fractures. The use of a uniplanar external fixator is an option for the treatment of fractures classified as Sanders types 2 and 3. Satisfactory reduction and stabilisation of the fracture are achieved by means of mini-incisions and fixator adjustment. The advantages of this technique include less soft-tissue damage, avoidance of internal implants and early weight-bearing with the potential to improve postoperative recovery.

External fixation of the thalamic portion of a fractured calcaneus: a new surgical technique

The optimal treatment for intra-articular calcaneus fractures remains controversial, despite internal fixation techniques providing good results. The major point of contention is the need to reconstruct the overall morphology versus to restore the anatomy of the subtalar joint perfectly. We will describe a two-stage technique for treating intra-articular calcaneus fractures in which the primary fracture line goes through the thalamic fragment. The first procedure focuses on the overall morphology by restoring the height and length with osteotaxis being accomplished with a medial external fixator. The second procedure consists of internal fixation through a minimally invasive lateral approach to restore the anatomy of the articular facets. Any defects are filled with injectable bone substitute. This novel technique is compared to the complication rates and radiology and anatomy outcomes in published studies. This two-stage surgical technique reduces the length of hospital stays and the number of complications.

Results of dynamic pedobarography following surgically treated intra-articular calcaneal fractures

OBJECTIVE

To investigate the clinical outcome and gait analysis findings by dynamic pedobarography in patients following surgically treated single, closed, dislocated intra-articular calcaneal fractures.

DESIGN

Retrospective single-center study with 26 patients. The average follow-up period was 34 months (range 18-61 months). We used the Zwipp score and a score based on a visual analog scale (VAS) to assess the subjective and objective clinical outcome. Dynamic pedobarography (EMED-M, 38 × 42 cm, four sensors per square centimeter, 50 Hz; Novel GmbH., Munich, Germany) was performed to retrieve gait patterns. Analysis was performed using the Emed-Software (Novel GmbH., Munich, Germany).

RESULTS

For the Zwipp score (±200 points), the average was +54.4 points (±48.2); for the VAS score (0-100 points), the average was 58.3 points (±24.3). There was limited mobility in the upper and lower ankle joint. Pedobarography showed a clearly disturbed gait with increased pressure for the fractured side (157 vs. 119 kPa) in the midfoot region (71.8 vs. 68 kPa) and under fifth metatarsal bone (234 vs. 160 kPa). The gait line was lateralized. The force-time-integral (fractured vs. healthy side) showed significant differences for the medial (18 vs. 7 N s) and lateral (61 vs. 36 N s) midfoot region.

CONCLUSIONS

We found only an average clinical outcome and clear pathological gait patterns in our cohort with lateralization of the gait line.

The treatment of intra-articular calcaneus fractures with severe soft tissue damage with a hinged external fixator or internal stabilization: long-term results

We developed a hinged external fixator for the treatment of dislocated intra-articular calcaneus fractures with severe soft tissue damage. The external fixation was performed with a known external fixator system. The screw insertion points were biomechanically tested by defining a virtual rotation axis through the center of the talus to allow early active motion in the ankle joint. Long-term follow-up was performed after an average of 7.3 years. Results were graded with the American Orthopaedic Foot and Ankle Society (AOFAS) score. Radiographs were reviewed according to Sanders classification. Four open fractures and 33 cases with extremely swollen soft tissue, blisters, or compartment syndromes were treated. In 24 cases (64.9%), the hinged fixator was the final method of treatment (group I). A change to open reduction with internal fixation was performed in 13 fractures (35.1%) when soft tissue problems were minimal (group II). There were no late amputations, osteomyelitis, or malunions. According to Sanders classification, group I consisted of 14 type II, 8 type III, and 2 type IV fractures. Pin loosening or pin infection was seen in 4 cases, but there was no redislocation. The Böhler's angle improved in 43%, gaps in the posterior facet were closed in 41%, and any shortening or deviation of the axis was corrected in 82% of the cases. The AOFAS score for the group averaged 66.5. According to Sanders classification, group II consisted of 8 type II and 5 type III fractures. The Böhler's angle improved in 88%, and gaps in the posterior facet were closed in 87%. Any shortening or deviation of the axis was corrected in 95%, and the AOFAS score averaged 61.3. Significant differences in patient outcome scores between open reduction with internal fixation and hinged fixator were not found. P value was > .05. The hinged external fixator frame can be used in all calcaneus fracture types without soft tissue limitation. The hinged fixator allows early movement in the ankle joint, the risk of infection is minimized, and secondary plate fixation remains possible.