Staged treatment of proximal tibial fracture using external locking compression plate

Finite element analysis comparison of Type 42A2 fracture fixed with external titanium alloy locking plate and traditional external fixation frame

BACKGROUND

At present, not all Type AO/OTA 42A2 open fractures can be treated by external fixation brackets, not to mention the inconvenience of this technique in clinical practice. External titanium alloy locking plates, which are lightweight and easy-to-operate, can be used as an alternative treatment option for such patients. However, there are few reports of finite element biomechanical analysis on the titanium alloy locking plates and fixation brackets being placed on the medial side of the tibial fracture. In this study, the biomechanical properties of titanium alloy locking plates and fixation brackets for treating Type AO/OTA 42A2 fractures were compared by applying the finite element method, and the results provided data support for the clinical application of the external titanium alloy locking plate technique.

METHODS

Type AO/OTA 42A2 fracture models were constructed using CT data of a male volunteer for two external fixation techniques, namely the external titanium alloy locking plate technique and the external fixation bracket technique, according to commonly-used clinical protocols. Then, the four-point bending, axial compression, clockwise rotation and counterclockwise rotation tests under the maximum load were simulated in finite element analysis software. The stress distribution, peak stress and overall tibial displacement data for the two different external fixation techniques were obtained and compared.

RESULTS

In the four different test conditions (i.e., four-point bending, axial compression, clockwise torsion, counterclockwise torsion) under the maximum load, the two external fixation techniques showed obvious von Mises stress concentration at the contacts between the screw and tibia, between the screw and titanium alloy locking plate, between the self-tapping self-drilling needle and tibia, between the self-tapping self-drilling needle and the external fixation device, as well as around the fracture end and around the cortical bone at the upper and lower ends of the tibia. The peak stress was ranged 26.67-558.77 MPa, all below the yield stress strength of titanium alloy. The peak tibial displacement of the external titanium alloy locking plate model was smaller than that of the fixation bracket model. In terms of structural stability, the external titanium alloy locking plate technique was superior to the external fixation bracket technique.

CONCLUSIONS

When fixing Type AO/OTA 42A2 fractures, external titanium alloy locking plates are not only lightweight and easy-to-operate, but also have better performance in terms of axial compression, bending and torsion resistance. According to the finite element biomechanical analysis, external titanium alloy locking plates are superior to traditional external fixation brackets in treating Type AO/OTA 42A2 fractures and can better meet the needs of clinical application.

Locking Compression Plate as an External Fixator for the Treatment of Tibia Infected Bone Defects

PURPOSE

This study was designed to observe the medium-term efficacy of an induced membrane technique combined with a locking compression plate as an external fixator for the treatment of tibia infected bone defects.

METHODS

Patients with a tibial infection were admitted to our department between January 2013 and November 2014. All patients were treated with the induced membrane technique. In the first stage, polymethyl methacrylate (PMMA) cement was implanted in the defects after debridement and then fixed with a locking compression plate (LCP) as an external fixator. In the second stage, bone grafts were implanted to rebuild the defects. The external plates were replaced with nails in 57 patients (internal group), and the remaining 30 patients were not exchanged with fixation (external group). The infection control rate, bone union rate, and complications of the two groups were compared.

RESULTS

Eighty-seven patients were enrolled in this study, and all patients had a minimum follow-up of 5 years (average 62.8 months) after grafting. Eighty-three patients (95.4%) achieved bone union, and the average union time was 6.77 months. Five patients (5.7%) experienced recurrence of infection. Complications included pin tract infection, fixation loosening, deformity connection, and limitation of joint range of motion (ROM). No significant differences in the infection control rate or bone defect union rate were noted between the two groups. The overall rate of complications in the external group was 50%, which was greater than that noted in the internal group (21.1%).

CONCLUSIONS

Locking compression plates are external fixators with smaller sizes that are easier to operate than conventional annular fixators or assembled external fixators. The use of locking compression plates in combination with the induced membrane technique in the treatment of tibia infected bone defects can achieve good clinical efficacy after medium-term follow-up.

Single-Stage Externalized Locked Plating for Treatment of Unstable Meta-Diaphyseal Tibial Fractures

(1) Background: Unstable meta-diaphyseal tibial fractures represent a heterogeneous group of injuries. Recently, good clinical results have been reported when applying a technique of externalized locked plating in appropriate cases, highlighting its advantage in terms of less additional tissue injury compared with conventional methods of fracture fixation. The aims of this prospective clinical cohort study were, firstly, to investigate the biomechanical and clinical feasibility and, secondly, to evaluate the clinical and functional outcomes of single-stage externalized locked plating for treatment of unstable, proximal (intra- and extra-articular) and distal (extra-articular), meta-diaphyseal tibial fractures. (2) Methods: Patients, who matched the inclusion criteria of sustaining a high-energy unstable meta-diaphyseal tibial fracture, were identified prospectively for single-stage externalized locked plating at a single trauma hospital in the period from April 2013 to December 2022. (3) Results: Eighteen patients were included in the study. Average follow-up was 21.4 ± 12.3 months, with 94% of the fractures healing without complications. The healing time was 21.1 ± 4.6 weeks, being significantly shorter for patients with proximal extra- versus intra-articular meta-diaphyseal tibial fractures, p = 0.04. Good and excellent functional outcomes in terms of HSS and AOFAS scores, and knee and ankle joints range of motion were observed among all patients, with no registered implant breakage, deep infection, and non-union. (4) Conclusions: Single-stage externalized locked plating of unstable meta-diaphyseal tibial fractures provides adequate stability of fixation with promising clinical results and represents an attractive alternative to the conventional methods of external fixation when inclusion criteria and rehabilitation protocol are strictly followed. Further experimental studies and randomized multicentric clinical trials with larger series of patients are necessary to pave the way of its use in clinical practice.

A Combination of Ilizarov Frame, Externalized Locking Plate and Tibia Bridging for an Adult with Large Tibial Defect and Severe Varus Deformity Due to Chronic Osteomyelitis in Childhood: A Case Report

Background: Various techniques have been reported to treat large, segmental tibial defects, such as autogenous bone graft, vascularized free fibula transfer and bone transport. We present a case of a 24-year-old male with a 17-year history of chronic osteomyelitis with obvious lower limb length discrepancy and severe varus deformity of the tibia secondary to osteomyelitis in childhood. Aim: The aim of this work is to provide an alternative choice for treating patients in developing countries with severe lower limb deformity caused by chronic osteomyelitis. Case Presentations: Without surgical intervention for a prolonged period of time, the patient was admitted in our institute for corrective surgery. Corrective surgery consisted of three stages: lengthening with Ilizarov frame, removal of Ilizarov frame and fixation with externalized locking plate, and removal of externalized locking plate. Tibia bridging was achieved at the distal and proximal junction. The range of motion (ROM) of the knee joint was nearly normal, but the stiffness of the ankle joint was noticeable. The remaining leg discrepancy of 0.1 cm required no application of a shoe lift. Moreover, the patient could engage in daily activities without noted limping. Conclusions: Distraction-compression osteogenesis using the Ilizarov apparatus is a powerful tool to lengthen the shortened long bone and adjust the deformity of the lower limbs. Externalized locking plates provide an alternative to the traditional bulky external fixator, as its low profile makes it more acceptable to patients without compromising axial and torsional stiffness. In all, a combination of Ilizarov frame, externalized locking plate and tibia bridging is an alternative for patients in similar conditions.

Evaluation of a novel semicircular locking external fixator for treating fractures of long bones: Biomechanical comparison with a circular external fixator

PURPOSE

This study aimed to investigate the biomechanical properties of a novel semicircular locking external fixator with locking screw mechanism, shape of trapezoidal corrugations, half- ring designed for greater stability.

MATERIALS AND METHODS

The novel external fixator had a half-ring with the shape of trapezoidal corrugations and locking screws fixing the bone at different angles in all three planes (sagittal, axial, and coronal). The biomechanical properties of the semicircular locking external fixator (group 1) were compared with those of a standard Ilizarov-type circular external fixator (group 2) (TST, İstanbul, Turkey) in an experimental study design. Five frames were used in each group. Standard PE 1000 (polyethylene) rod models (n = 10) simulating the tibia bone model were used. Both systems were compared biomechanically by applying axial and torsional loads simultaneously.

RESULT

Two samples in group 2 were damaged before the test ended during axial loading. All of the samples in group 1 completed the tests without damage after 150,000 cycles. The axial stiffness of the semicircular locking external fixator was found to be significantly higher than that of the Ilizarov-type circular external fixator (p < 0.05). No statistically significant difference was found between the two fixators in torsional loading. The application time of semicircular locking external fixator was significantly shorter than Ilizarov-type circular external fixator (p < 0.05).

CONCLUSION

The novel semicircular locking external fixator was biomechanically stronger than the Ilizarov-type external fixator for treating fractures of long bones. It can be used as a permanent external fixator for the definitive treatment of long bone fractures with soft tissue damage in terms of stability and application time.

Comparison between external locking plate fixation and conventional external fixation for extraarticular proximal tibial fractures: a finite element analysis

Background

Good clinical outcomes for locking plates as an external fixator to treat tibial fractures have been reported. However, external locking plate fixation is still generally rarely performed. This study aimed to compare the stability of an external locking plate fixator with that of a conventional external fixator for extraarticular proximal tibial fractures using finite element analysis.

Methods

Three models were constructed: (1) external locking plate fixation of proximal tibial fracture with lateral proximal tibial locking plate and 5-mm screws (ELP), (2) conventional external fixation of proximal tibial fracture with an 11-mm rod and 5-mm Schanz screws (EF-11), and (3) conventional external fixation of a proximal tibial fracture with a 7-mm rod and 5-mm Schanz screws (EF-7). The stress distribution, displacement at the fracture gap, and stiffness of the three finite element models at 30-, 40-, 50-, and 60-mm plate–rod offsets from the lateral surface of the lateral condyle of the tibia were determined.

Results

The conventional external fixator showed higher stiffness than the external locking plate fixator. In all models, the stiffness decreased as the distance of the plate–rod from the bone surface increased. The maximum stiffness was 121.06 N/mm in the EF-11 model with 30-mm tibia–rod offset. In the EF-7 model group, the maximum stiffness was 40.00 N/mm in the model with 30-mm tibia–rod offset. In the ELP model group, the maximum stiffness was 35.79 N/mm in the model with 30-mm tibia–plate offset.

Conclusions

Finite element analysis indicated that external locking plate fixation is more flexible than conventional external fixation and can influence secondary bone healing. External locking plate fixation requires the placement of the plate as close as possible to the skin, which allows for a low-profile design because the increased distance from the plate to the bone can be too flexible for bone healing. Further experimental mechanical model tests are necessary to validate these finite element models, and further biological analysis is necessary to evaluate the effect of external locking plate fixation on fracture healing.

A novel low-profile external skeletal fixator for type IIIB open tibial fractures: A biomechanical and clinical pilot study

BACKGROUND

Although external fixator is standard for managing staged treatment of open tibial fracture, the main disadvantage of this device is too bulky to be tolerated by most patients for longtime use. The purposes of this pilot study were to compare the biomechanical properties of a novel low-profile external fixator (LP-ESF) with a traditional ESF and also to evaluate its performance in patients with Gustilo type IIIb tibial open fractures.

METHODS

A prospective clinical pilot study started from January 2015 to December 2017, and 18 patients with Gustilo type IIIb open tibial fractures underwent the fixation with a novel LP-ESF system. The biomechanical properties of the LP-ESF were compared with the Synthes External Fixation System according to the standard ASTM F1541-02. These patients were divided into two groups according to the size of bony defect. The postoperative clinical outcomes were subsequently collected.

RESULTS

The biomechanical properties of the LP-ESF were comparable with those of Synthes External Fixation System and had an improved the axial/torsional stiffness and ultimate strength. In the clinical study, all patients with LP-ESF had fracture union. The duration of application of LP-ESF was 3.5 to 18 months until fracture union. In 10 of 18 patients, their fractures were immobilized with the LP-ESF until bone union, and no pin tract infection and no chronic osteomyelitis were recorded. The 36-Item Short Form Health Survey life quality and health survey were good to excellent in these patients. Notably, the LP-ESF allowed a patient with severe bone and soft-tissue defects to preserve the leg and joints function.

CONCLUSION

In this study, we found that the novel LP-ESFs had improved clinical outcomes. The long-term LP-ESF application seems to be tolerable in our patients. This novel approach permits better controls in deep infection and faster healing of fractures, and thus may provide a viable alternative treatment for Gustilo type IIIb open tibial fractures.

Locked plating as an external fixator in treating tibial fractures: A PRISMA-compliant systematic review

OBJECTIVES

This article is a systematic review of the published literature about the biomechanics, functional outcomes, and complications of a locked plate as an external fixator in treating tibial fractures.

METHODS

We searched the PubMed, Ovid Medline, Embase, ScienceDirect, and Cochrane Library databases to retrieve the relevant studies. Studies published in English and Chinese which assessed adult patients and more than 4 cases who had sustained any type of fresh tibial fracture treated with the external locking plate, provided that they reported functional outcomes, range of motion (ROM), union or complication rates, and the biomechanical studies of external locked plating are also included.

RESULTS

The electronic search strategy revealed 248 studies, and 2 studies were identified as relevant through manual search of references. Finally, 12 studies were included in this systematic review. These consist of 3 pure biomechanical studies, 8 case series, and 1 study including both of biomechanics and case series. Due to the heterogeneity of biomechanical studies, we can only conclude that external locked plate shows inferior structural stiffness than internal locked plate. The clinical studies reported that external locked plating gave a satisfactory ROM of the knee and ankle, functional outcomes, union rate, and low complication rate.

CONCLUSIONS

We can only conclude that external locked plate shows inferior structural stiffness than internal locked plate because of the heterogeneity of biomechanical studies. The clinical studies showed locked plating as an external fixator in treating tibial fractures can be considered as a safe and successful procedure. However, as yet, there is unconvincing evidence that it is superior to standard techniques with regards to clinical and functional outcomes. More and well-designed studies about this technique should be carried out.

Externalised locking compression plate as an alternative to the unilateral external fixator: a biomechanical comparative study of axial and torsional stiffness

Objectives

External fixators are the traditional fixation method of choice for contaminated open fractures. However, patient acceptance is low due to the high profile and therefore physical burden of the constructs. An externalised locking compression plate is a low profile alternative. However, the biomechanical differences have not been assessed. The objective of this study was to evaluate the axial and torsional stiffness of the externalised titanium locking compression plate (ET-LCP), the externalised stainless steel locking compression plate (ESS-LCP) and the unilateral external fixator (UEF).

Methods

A fracture gap model was created to simulate comminuted mid-shaft tibia fractures using synthetic composite bones. Fifteen constructs were stabilised with ET-LCP, ESS-LCP or UEF (five constructs each). The constructs were loaded under both axial and torsional directions to determine construct stiffness.

Results

The mean axial stiffness was very similar for UEF (528 N/mm) and ESS-LCP (525 N/mm), while it was slightly lower for ET-LCP (469 N/mm). One-way analysis of variance (ANOVA) testing in all three groups demonstrated no significant difference (F(2,12) = 2.057, p = 0.171).

There was a significant difference in mean torsional stiffness between the UEF (0.512 Nm/degree), the ESS-LCP (0.686 Nm/degree) and the ET-LCP (0.639 Nm/degree), as determined by one-way ANOVA (F(2,12) = 6.204, p = 0.014). A Tukey post hoc test revealed that the torsional stiffness of the ESS-LCP was statistically higher than that of the UEF by 0.174 Nm/degree (p = 0.013). No catastrophic failures were observed.

Conclusion

Using the LCP as an external fixator may provide a viable and attractive alternative to the traditional UEF as its lower profile makes it more acceptable to patients, while not compromising on axial and torsional stiffness.

Cite this article: B. F. H. Ang, J. Y. Chen, A. K. S. Yew, S. K. Chua, S. M. Chou, S. L. Chia, J. S. B. Koh, T. S. Howe. Externalised locking compression plate as an alternative to the unilateral external fixator: a biomechanical comparative study of axial and torsional stiffness. Bone Joint Res 2017;6:216–223. DOI: 10.1302/2046-3758.64.2000470.

Comparison of closed reduction and expert tibial nailing with open reduction and plate and screw fixation in the treatment of two segmental tibial fractures

PURPOSE

To compare the outcomes of closed reduction and expert tibial nailing (ETN) versus open reduction and plate and screw fixation in treating two segmental tibial fractures.

METHODS

This study included 53 cases of two segmental fractures of the tibial shaft. They were admitted to our department between March 2010 and June 2013 and treated respectively by closed reduction and ETN (ETN group, n=31) or open reduction fixation with plate and screws (PS group, n=22). The general data of two groups including gender, age, injury cause, fracture type, etc showed no significant difference (p>0.05). To compare the therapeutic effects between two groups, the intraoperative condition, post- operative function and related complications were investigated.

RESULTS

All the patients were successfully followed up. The period was 19.2 months for ETN group and 20.5 months for PS group. All the fractures in ETN group had union without complications such as malunion, infection, or osteofascial compartment syndrome; whereas there were 3 cases of superficial infection cured by repeated dressing change and 2 cases of delayed union in PS group. The total incidence of complication in PS group was 22.7% (5/22), much higher than that in ETN group (p<0.05). Moreover, ETN group showed a better result in terms of intraoperative blood loss, operation time, postoperative weight bearing time and fracture union time. In ETN group, at one-year follow-up, Johner-Wruhs' criteria was adopted to assess the postoperative function, which was reported as excellent in 18 cases, good in 10 cases and fair in 3 cases in ETN group (100% excellent-good rate). While in PS group, the result was excellent in 10 cases, good in 7 cases, fair in 3 cases and poor in 2 cases (77.3% excellent-good rate). The comparison was insignificant (p>0.05).

CONCLUSION

Compared with plate and screw fixation, ETN fixation has the advantages of fewer complications, shorter operation time, being less invasive, earlier postoperative rehabilitation and weight bearing, quicker fracture union and better functional recovery, thus being an effective way to treat two segmental tibial fractures.