The use of computer navigation in performing minimally invasive surgery for intertrochanteric hip fractures--The experience in Singapore

Outcomes following minimally invasive plate osteosynthesis (MIPO) application in tibial pilon fractures - A systematic review

BACKGROUND

This systematic review evaluates postoperative complications and functional outcomes of minimally invasive plate osteosynthesis (MIPO) for distal tibial pilon fractures. This paper aims to fill a key literature gap, as no previous reviews have specifically addressed MIPO for tibial pilon fractures or fractures other than those involving the humeral shaft.

METHODS

This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A systematic literature search was done using PubMed, Embase, Web of Science, and Scopus databases from 2000 to 2022. Inclusion criteria were MIPO treatment in skeletally mature patients, while exclusion criteria were non-English papers, conference abstracts, papers with multiple treatment modalities that didn't analyze MIPO outcomes separately, skeletally immature patients, case reports, and cohorts smaller than five patients. Unpublished papers were also searched using Clinical Trials. Data extraction included general study information, injury specification, outcome measures, and complications. Finally, a risk of bias assessment (RoB) was performed.

RESULTS

A total of 1732 studies were identified, of which 23 were included in this review, with 673 patients and 678 fractures analyzed. The mean follow-up ranged from 6 to 62.53 months, with most studies representing intermediate to long-term follow-up. Primary outcome measures showed that 87.33% achieved 'excellent to good' results, 8.67% achieved 'fair' results, and 4% achieved 'poor' results. Stratified by fracture type, 76.47%, 80.05%, and 76.92% of AO/OTA type A, B, and C fractures, respectively, achieved 'excellent to good' results. 35.06% of cases reported complications (236 in total). These included one case of deep infection (0.148%), 28 superficial wound infections (4.16%), 4 nonunion cases (0.59%), and 22 malunion instances (3.27%). RoB assessment showed that 52.17% had a moderate overall risk of bias, 39.13% had a serious overall risk of bias, and 8.7% had a critical overall risk of bias.

CONCLUSION

MIPO technique for pilon fractures showed good functional outcomes and reliability, with low complication rates and should be considered in cases where proper indirect reduction is possible. However, while the evidence is promising, further high-quality studies with larger sample sizes, longer-term follow-up, and comparison to other techniques are needed to evaluate the efficacy and safety of this technique.

LEVEL OF EVIDENCE

IV.

ADAPT system is a dramatic advance in computer-assisted surgery for femoral trochanteric fractures

Introduction: In recent years, computer-assisted surgery has made it possible to undergo surgery with a high degree of precision. This study aimed to investigate the usefulness of computer-assisted surgery for femoral trochanteric fractures using the ADAPT (ADAptive Positioning Technology) system. Methods: A total of forty patients with femoral trochanteric fracture underwent intramedullary nailing for fracture fixation: in twenty patients, the ADAPT system (ADAPT group), and in the other twenty, it was not used (control group). The operative time, intraoperative fluoroscopy time, tip apex distance (TAD), and tip to head surface distance (TSD) were measured and compared between the two groups to assess the efficiency and accuracy of the surgery. Results: The operative time was significantly shorter (P < 0.05), intraoperative fluoroscopy time was significantly reduced (P < 0.01), and implant placement was significantly better in the ADAPT group (P < 0.01). Conclusion: Navigation systems have been developed to improve the efficiency of surgery. The ADAPT system was considered a very useful device for intramedullary nailing of femoral trochanteric fractures, as it reduced the intraoperative fluoroscopy time and improved the accuracy of implant placement, also reducing the operative time.

Computer-Assisted Orthopedic and Trauma Surgery

BACKGROUND

There are many ways in which computer-assisted orthopedic and trauma surgery (CAOS) procedures can help surgeons to plan and execute an intervention.

METHODS

This study is based on data derived from a selective search of the literature in the PubMed database, supported by a Google Scholar search.

RESULTS

For most applications the evidence is weak. In no sector did the use of computer-assisted surgery yield any relevant clinical or functional improvement. In trauma surgery, 3D-navigated sacroiliac screw fixation has become clinically established for the treatment of pelvic fractures. One randomized controlled trial showed a reduction in the rate of screw misplacement: 0% with 3D navigation versus 20.4% with the conventional procedure und 16.6% with 2D navigation. Moreover, navigation-assisted pedicle screw stabilization lowers the misplacement rate. In joint replacements, the long-term results showed no difference in respect of clinical/functional scores, the time for which the implant remained in place, or aseptic loosening.

CONCLUSION

Computer-assisted procedures can improve the precision of certain surgical interventions. Particularly in joint replacement and spinal surgery, the research is moving away from navigation in the direction of robotic procedures. Future studies should place greater emphasis on clinical and functional results.

Radiation protection and standardization

X - Rays has become integral and indispensable part of health care diagnosis and intervention. Intervention procedures in Orthopedics surgery now mostly performed under image intensifiers (C-Arm) which involve the risks of occupational overexposure of radiation to the patients and health care personnel. The principles of radiation protection are helpful in keeping radiation exposure just adequate for diagnostic and intervention procedures. Regular surveillance of protective apparel is necessary for longevity of safety. It is responsibility of all OT personnel to know and implement radiation safety. Each situation involving X-ray radiation should include justification of the procedure, minimum radiation exposure just adequate for diagnostic and interventional procedures.

A motion compensation method for bi-plane robot-assisted internal fixation surgery of a femur neck fracture

Bi-plane robots have been widely applied in clinical use to place cannulated screws for internal fixation surgery of femur neck fractures, which is performed precisely and automatically using two online fluoroscopic images. However, the setup procedure of the bi-plane robot is empirical, and physicians usually have to re-run the setup procedure, exposing the patient to high doses of radiation in clinical applications. In this article, a motion compensation method is proposed by a novel use of the binocular vision principle to improve the bi-plane robot setup using two doses of radiation within 2 min. The entry point, exit point, and angle errors of the three-dimensional trajectory reconstruction are 1.23 ± 0.39 mm, 1.49 ± 0.49 mm, and 0.33° ± 0.23°, respectively. The motion compensation method significantly reduces the dose of radiation and the operation time of the setup procedure and has acceptable accuracy.

THE MINUS(®) SYSTEM MINIMALLY INVASIVE TECHNIQUE FOR THE TREATMENT OF TRANTROCHANTERIC FRACTURES

The MINUS system was developed as a minimally invasive procedure that uses a diaphyseal cephalic extramedullary implant for the treatment of transtrochanteral fractures of the femur in elderly patients. The implant consists of a sliding screw coupled to a plate adapted to the minimally invasive technique. The surgical access is approximately three centimeters in length located on the lateral surface of the hip, below the projection of the small trochanter. A perfectly adapted instrument was used for the procedure, which also requires the use of an image intensifier, reducing surgery time and rate of bleeding. The objective of this study is to present a new instrument and implant, developed specifically for treatment with the minimally invasive technique, reducing the length of the conventional surgical access from 10 to three centimetres. This new implant was given the commercial name of MINUS System.

Improved lag screw positioning in the treatment of proximal femur fractures using a novel computer assisted surgery method: a cadaveric study

Background

The importance of the tip-apex distance (TAD) to predict the cut-out risk of fixed angle hip implants has been widely discussed in the scientific literature. Intra-operative determination of TAD is difficult and can be hampered by image quality, body habitus, and image projection. The purpose of this paper is to evaluate, through a cadaveric study, a novel computer assisted surgery system (ADAPT), which is intended for intraoperative optimisation of lag screw positioning during antegrade femoral nailing. A 3D measure for optimal lag screw position, the tip-to-head-surface distance (TSD), is introduced.

Methods

45 intra-medullary hip screw procedures were performed by experienced and less experienced surgeons in a cadaveric test series: in 23 surgeries the ADAPT system was used, and in 22 it was not used. The position of the lag screw within the femoral head and neck was evaluated using post-operative CT scans. TAD, TSD, fluoroscopy as well as procedure time and variability were assessed.

Results

The use of the ADAPT system increased accuracy in TSD values (i.e. smaller variability around the target value) for both groups of surgeons (interquartile range (IQR) of experienced surgeons: 4.10 mm (Conventional) vs. 1.35 mm (ADAPT) (p = 0.004)/IQR of less experienced surgeons: 3.60 mm (Conventional) vs. 0.85 mm (ADAPT) (p = 0.002)). The accuracy gain in TAD values did not prove to be significant in the grouped analysis (p = 0.269 for experienced surgeons; p = 0.066 for less experienced surgeons); however, the overall analysis showed a significant increase in accuracy (IQR: 4.50 mm (Conventional) vs. 2.00 mm (ADAPT) (p = 0.042)). The fluoroscopy time was significantly decreased by the use of the ADAPT system with a median value of 29.00 seconds (Conventional) vs. 17.00 seconds (ADAPT) for the less experienced surgeons (p = 0.046). There was no statistically significant impact on the procedure time (p = 0.739).

Conclusions

The ADAPT system improved the position of the lag screw within the femoral head, regardless of the surgeon’s level of clinical experience, and at the same time decreased overall fluoroscopy usage. These positive effects are achieved without increasing procedure time.

Measurement of three-dimensional morphological characteristics of the calcaneus using CT image post-processing

Background

Although computed tomography (CT) with three-dimensional (3D) rendering of the calcaneus is used for diagnostic evaluation of disorders, morphological measurements for the calcaneus are mostly based on a two-dimensional plane. The purposes of this study were to design a method for 3D morphological measurements of the normal calcaneus based on CT post-processing techniques, to measure morphological parameters in the male and female groups and describe gender differences of the parameters, and to investigate the reliability of such measurements.

Methods

One hundred and seventy-nine patients (83 men and 96 women) with a mean age of 40.6 (range, 21 to 59) years who underwent CT scans for their feet were reviewed retrospectively. The 3D structure of a normal calcaneus after shaded surface display reconstruction was extracted by interactive and automatic segmentation. Morphological measurements were achieved by means of a 3D measurement method based on CT image post-processing. Lengths and heights of the main parts of the calcaneus, Gissane’s angle, Böhler’s angle and the area of articular facet were worked out in 3D space. Gender-related size differences of parameters were compared using analysis of covariance (ANCOVA), adjusting for body height. Intra-observer and inter-observer reliabilities were assessed using intraclass correlation coefficients (ICCs) and the root mean square standard deviation (RMS-SD) for precision study.

Results

A large range of measurement values was found. Only the length of the anterior process was without gender difference (p > 0.05). The other parameters in the male group were greater than those in the female group (p < 0.01 for each, ANCOVA). All parameters had excellent reliability and reproducibility (ICC > 0.8). Precision was acceptable for intra-observer RMS-SD (linear, angular and areal measurements no more than 0.6 mm, 1.2° and 0.25 mm², respectively). Inter-observer RMS-SD ranged from 0.4 to 1.6 mm for linear measurements, 1.2 to 2.5° for angles and 0.24 to 0.40 mm² for areas.

Conclusions

Three-dimensional morphological measurement based on a CT post-processing technique was highly reliable and repeatable for calcaneal anatomic morphological measurement. The current data will be helpful for anatomic reduction of calcaneal fractures and calcaneal malunion.

2D-fluoroscopic based navigation for Gamma 3 nail insertion versus conventional procedure- a feasibility study

Background

Intramedullary nailing is a standard surgical procedure for fixation of proximal femoral fractures, but is associated with considerable radiation exposure for controlling the implant placement, due to the percutaneous insertion technique.

The aim of this study was the evaluation of potential benefits of 2D-fluoroscopic based navigation focused on the reduction of radiation exposure, a decrease of procedure time, as well as an increase of accuracy for Gamma3 nail insertions.

Methods

Twenty randomized Gamma3 nail insertions were performed in non-fractured synthetic femora according to the manufactures operation guidelines (group I) or with use of a 2D-fluoroscopic based navigation system (group II). Time of different steps of the procedure and the radiation exposure were measured, as well as the accuracy evaluated in postoperative CT scans.

Results and discussion

All Gamma3 nails were placed without any technical problems. Independent of the used procedure, the overall operating time (group I: 584 ± 99.2 sec; group II: 662 ± 64.9 sec; p=0.06) and accuracy of the final nail-positions were equivalent, but the radiation exposure was significantly reduced (92% reduction in fluoroscopic images and 91% reduction in fluoroscopic time, p< 0.01), using the 2D fluoroscopic based navigation procedure.

Conclusions

2D-fluoroscopic based navigation for Gamma3 nail insertion facilitates a relevant reduction of radiation exposure with equivalent accuracy of the final implant position and no prolonged operating time. This promising procedure modification is independent of different cephalomedullary implant manufacturers and specific implant designs, but needs to be evaluated in further clinical settings.

Evaluation of a new computer-assisted surgical planning and navigation system based on two-dimensional fluoroscopy for insertion of a proximal femoral nail: an experimental study

Pertrochanteric femoral fractures are common and intramedullary nailing is an accepted method for their surgical treatment. Accurate placement of the implant is essential to ensure fixation. The conventional technique can require multiple guide wire passes, and relies heavily on fluoroscopy. A computer-assisted planning and navigation system based on two-dimensional fluoroscopy for guide wire placement in the femoral neck has been developed, in order to perform intramedullary pertrochanteric fracture fixation using the proximal femoral nail (PFNA). The planning process was supported by a 'zero-dose C-arm navigation' system. The PFNA was inserted into 12, intact, femoral sawbones guided by the computer-based navigation, and into 12, intact, femoral sawbones using a conventional fluoroscopic-assisted technique. Guide wire and subsequent blade placement in the femoral neck was evaluated. The computer-assisted technique achieved a significant decrease in the number of required fluoroscopic images and in the number of guide wire passes. The obtained average blade placement accuracy in the femoral neck was equivalent to the conventional technique. The operation time was significantly longer in the navigation-assisted group. The addition of computer-assisted planning and surgical guidance to the intramedullary nailing of pertrochanteric femoral fractures offers a number of clinical benefits based on the results of this sawbone study. Further studies including fractured sawbones and cadaver models with extension of the navigation process to all steps of PFNA introduction and with the goal of reducing operation time are indispensable before integration of this navigation system into clinical practice.

Review: Minimally Invasive Versus Conventional Dynamic Hip Screw Fixation in Elderly Patients With Intertrochanteric Fractures: A Systematic Review and Meta-Analysis

The classic dynamic hip screw fixation of intertrochanteric fractures may be associated with significant blood loss and soft tissue damage, which may worsen existing comorbidities of frail elderly patients. Recently, minimally invasive dynamic hip screw (MIDHS) technique was developed for osteosynthesis of intertrochanteric fractures. A highly sensitive search strategy was used to identify all published randomized or quasi-randomized controlled trials (RCTs/ qRCTs) and comparative observational studies comparing the MIDHS technique with the conventional dynamic hip screw (CDHS) technique in patients with intertrochanteric fractures. A pooled estimate of effect size was produced using both random and fixed effects models. Four RCTs/qRCTs and 2 retrospective comparative studies were identified. The MIDHS technique resulted in less blood loss, shorter hospitalization, lower pain level, faster fracture healing, and better hip function when compared with the CDHS technique. There was no significance difference between the 2 groups with regard to postoperative complications and implant position. The MIDHS technique may achieve perioperative benefits when compared with the CDHS technique.

Evaluation of a fluoroscopy-based navigation system enabling a virtual radiation-free preview of X-ray images for placement of cannulated hip screws. A cadaver study

Accurate placement of cannulated screws is essential to ensure fixation of medial femoral neck fractures. The conventional technique may require multiple guide wire passes, and relies heavily on fluoroscopy. A computer-assisted planning and navigation system based on 2D fluoroscopy for guide wire placement in the femoral neck has been developed to improve screw placement. The planning process was supported by a tool that enables a virtual radiation-free preview of X-ray images. This is called "zero-dose C-arm navigation". For the evaluation of the system, six formalin-fixed cadaveric full-body specimens (12 femurs) were used. The evaluation demonstrated the feasibility of fluoroscopically navigated guide wire and implant placement. Use of the novel system resulted in a significant reduction in the number of fluoroscopic images and drilling attempts while achieving optimized accuracy by attaining better screw parallelism and enlarged neck-width coverage. Operation time was significantly longer in the navigation assisted group. The system has yielded promising initial results; however, additional studies using fractured bone models and with extension of the navigation process to track two bone fragments must be performed before integration of this navigation system into the clinical workflow is possible, and these studies should focus on reducing the operation time.

[Evaluation of a 2D fluoroscopy-based navigation system for insertion of femoral neck screws. An experimental study]

INTRODUCTION

The aim of this study was the evaluation of a new computer-assisted planning and navigation system based on 2D-fluoroscopy for guidewire insertion in order to perform cannulated screw placement into the femoral neck. The image acquisition process was supported by a radiation-saving procedure called Zero-dose C-arm navigation.

MATERIAL AND METHODS

In the context of a sawbone study, we performed insertion of 3 cannulated screws positioned under navigation control as well as using the conventional technique in 12 sawbones. Both procedures were performed using open and closed techniques.

RESULTS

The computer-assisted technique significantly reduced the amount of intraoperative fluoroscopic images (open technique: -14±3 images, closed technique: -29.4±6 images). Drilling attempts were reduced in the computer-assisted groups (open technique: -1.2±1 attempts, closed technique: -1.7±1.5 attempts) and the femoral neck area covered by the screws was greater in the navigation-assisted groups (open technique: +32.1±16.3 mm(2), closed technique: +32.6±14.9 mm(2)), There was no difference concerning parallelism of the screws or perforation of femoral neck or head. The operation time was significantly longer in the navigation-assisted groups (open technique: +24.2±2.1 min, closed technique: +22.8±5.8 min).

CONCLUSION

The addition of computer-assisted planning and surgical guidance supported by Zero-dose C-arm navigation can be useful for the fixation of medial femoral neck fractures with cannulated screws. Further studies with the goal of reducing the operation time are indispensable before integrating this navigation system into the clinical workflow.

Computer-assisted trauma surgery

Computer-assisted orthopaedic surgery (CAOS) is performed by digitizing the patient's anatomy, combining the images in a computerized system, and integrating the surgical instruments into the digitized image background. This allows the surgeon to navigate the surgical instruments and the bone in an improved, virtual visual environment. CAOS in traumatology is performed with images obtained by fluoroscopy, CT, or three-dimensional fluoroscopy. CAOS is used in basic trauma procedures for preoperative planning, fracture reduction, intramedullary nailing, percutaneous screw or plate fixation, and hardware or shrapnel removal. Potential benefits of CAOS include minimal invasiveness, increased accuracy, and decreased radiation exposure. Limitations include a significant learning curve, increased surgical time, requirements for special setup and equipment handling in the operating room, specialized technical support, and cost. Current evidence shows no advantage with CAOS in trauma cases compared with conventional methods. Prospective randomized trials and clinical outcomes are lacking.

The accuracy and precision of computer assisted surgery in the assessment of frontal plane deviations of the lower extremity: a femoral fracture model

OBJECTIVES

Mechanical axis deviation of the lower extremity as a result of malreduction or malunion of fractures plays an important role in the development of arthritis. Therefore it is crucial to restore the limb alignment as accurate as possible. The purpose of this study was to evaluate the accuracy and precision of navigation in assessing isolated frontal plane (varus/valgus) deviations of the lower limb in a simulated fracture model of the femur.

MATERIALS AND METHODS

Three fracture models with ten specimens in each were created in femoral synthetic composite bones to simulate a subtrochanteric (AO/OTA 31-A1), mid-diaphyseal (AO/OTA 32-A3), and supracondylar (AO/OTA 33-A1) femur fracture. Each specimen was mounted on a custom holding device and registered with the navigation system. Eight custom-made aluminum wedges of varying angles (5 degrees -26 degrees ) were used to create varus/valgus angulations at the fracture site. After wedge placement, the frontal plane deformity was recorded and registered by the navigation system. The means and standard deviations for each navigated wedge angle were calculated and compared to the actual wedge angle using a one sample t test. A single factor ANOVA test was subsequently performed to see if the differences between the navigated mean angles in each fracture group were statistically significant. The level of significance was defined as P < 0.05.

RESULTS

None of the navigated mean angles were found to be significantly different from the actual wedge angles (P = 0.05-1.00). More specifically, the differences between the navigated mean angles and the actual wedge angles ranged from 0 degrees to 0.7 degrees . Furthermore, the differences between the navigated mean angles in each angle group were found to be statistically insignificant (P = 0.53-0.99).

CONCLUSION

The high accuracy and precision of navigation systems in determining frontal plane deformities of long bones can make them an invaluable tool for the exact reduction and realignment of lower extremity fractures.

Minimally invasive hip fracture surgery: are outcomes better?

OBJECTIVES

Intertrochanteric hip fractures have high morbidity and mortality rates. The purpose of this study was to determine if minimally invasive plating, nailing, or external fixation operations lead to improved outcomes for intertrochanteric hip fractures compared with standard insertion of a sliding hip screw (SHS).

DATA SOURCES

A systematic search of MEDLINE (1996 to June 2007) and EMBASE (1980 to June 2007) was performed. Results were limited to English language studies. References from eligible studies were reviewed to identify additional studies.

STUDY SELECTION

Studies were selected for review based on the following criteria: prospective or retrospective studies comparing minimally invasive plating, nailing, or external fixation to standard insertion of an SHS, exclusion of intracapsular and subtrochanteric hip fractures, and report of outcome data by treatment group to allow for comparison.

DATA EXTRACTION

The following outcomes were extracted from eligible studies: operative time, operative blood loss, intraoperative complications, postoperative drop in hemoglobin, postoperative pain, postoperative medical or fracture complications, wound complications, length of hospital stay, and post-fracture function.

DATA SYNTHESIS

Sufficient data existed among 14 randomized controlled trials to perform a meta-analysis and calculate pooled relative risks for failure of fixation, blood transfusion, and mortality. Relative risks were calculated with 95% confidence intervals using a random-effects model, and an analysis of heterogeneity between pooled studies was conducted. Other outcome measures that were extracted from 17 comparative studies are reported as a systematic review.

CONCLUSIONS

Although a significant heterogeneity exists between pooled studies, minimally invasive hip fracture plating, nailing, or external fixation was associated with a decrease in transfusion rate [relative risk of 0.63 as compared to standard SHS (95% confidence interval 0.41 to 0.96; I(2) = 83.6%)]. There was no significant difference for the other comparisons, including mortality between minimally invasive plating, nailing, or external fixation and standard insertion of an SHS.

Innovations in osteosynthesis and fracture care

Over the years giant steps have been made in the evolution of fracture fixation and the overall clinical care of patients. Better understanding of the physiological response to injury, bone biology, biomechanics and implants has led to early mobilisation of patients. A significant reduction in complications during the pre-operative and post-operative phases has also been observed, producing better functional results. A number of innovations have contributed to these improved outcomes and this article reports on the advances made in osteosynthesis and fracture care.