Percutaneous Scaphoid Fixation Research Articles

Robot-assisted percutaneous scaphoid fixation: patient-reported outcomes and learning curve at two centres.

This study describes patient-reported outcomes of robot-assisted percutaneous scaphoid fracture fixation of 62 patients from two medical centres and the learning curve of this new technique. One attempt to place the guidewire was sufficient in 97% of cases. All fractures achieved radiographic union at a mean of 9 weeks. There were no complications observed. At a mean follow-up of 36 months (range 12-68 months), the mean patient-rated wrist evaluation (PRWE) was 2 (range 0-22) and the mean Mayo Wrist Score was 96 (range 70-100). After the initial ten to 20 cases, the learning phase was reasonably surmountable with a marked reduction of operative duration and improvement of the screw accuracy.Level of evidence: IV.

A comparative cadaveric study for percutaneous scaphoid fixation: robotic vs freehand.

To compare the robotic-assisted and the traditional freehand percutaneous scaphoid fixation in number of guidewire attempts, duration of fluoroscopy time, amount of radiation dose, and screw centrality. Twenty cadaveric specimens were randomized into either the robotic or freehand group. The scaphoids in both groups were fixed by either the same attending or resident from our hand surgery department. The operation duration, amount of radiation from intraoperative fluoroscopy, total fluoroscopy time, and the number of guidewire attempts were documented and compared. Postoperatively, all the specimens had a computed tomography (CT) scan performed, and the difference in the final position of the screw and the central axis of the scaphoid was examined. In the robotic group, all the guide wires were satisfactorily positioned within a single attempt, while the median number of attempts in the traditional freehand group was 18 (quaternion 14-65). This also meant that the surgeon in the robotic group experienced significantly lower radiation exposure dose and time as compared to the freehand group. There were no significant differences in the final screw position as compared to the central axis of the scaphoid in both groups. Although there was no difference in surgeon performance in the robotic group, the operative time for the attending was significantly lower as compared to the resident in the freehand group. Robotic-assisted surgery for scaphoid fracture fixation is superior to the traditional freehand method as it facilitates accurate screw placement with lower radiation exposure and fewer guide wire attempts.

Ultrasound-Based Registration for the Computer-Assisted Navigated Percutaneous Scaphoid Fixation.

An ultrasound (US)-based computer-assisted approach has the potential to improve the accuracy and precision of screw placement for the percutaneous fixation of scaphoid fractures and also reduce the radiation dose for patient and clinical staff. Therefore, a surgical plan based on preoperative diagnostic computed tomography (CT) is registered with intraoperative US images, enabling a navigated percutaneous fracture fixation. However, approaches published so far rely on semimanual methods for intraoperative registration and are limited by long computation times. To address these challenges, we propose the employment of deep learning-based methods for US segmentation and registration in order to achieve a fast and fully automated yet robust registration process. For validation of the proposed US-based approach, we first provide a comparison of methods for segmentation and registration, assess their contribution to the overall error throughout our pipeline, and, finally, evaluate navigated screw placement in an in vitro study on 3-D printed carpal phantoms. Successful screw placement has been achieved for all ten screws, with deviations from the planned axis of 1.0 ± 0.6 and 0.7 ± 0.3 mm at the distal and proximal pole, respectively. The complete automation and total duration of about 12 s also allow seamless integration of our approach into the surgical workflow.

Mixed Reality Assisted Percutaneous Scaphoid Fixation: A Proposed New Surgical Technique.

The success of percutaneous fixation of non or minimally displaced scaphoid waist fractures is reliant on optimal placement of the screw. This can be challenging for surgeons to achieve, potentially involving a large volume of intraoperative imaging, and surgical time. Mixed reality (MR) is a new technology that allows the projection of holographic imagery within the surgeon's field of vision intraoperatively. This imagery can include surgical planning data and 3D reconstructions of a patient's anatomy that can be used in order to aid the surgeon in achieving accuracy. We describe a technique for how this novel technology might be used in the future to fix scaphoid fractures-MR assisted percutaneous scaphoid fixation. This is done using cadaveric modeling. MR assisted percutaneous scaphoid fixation may have the potential to aid surgeons in achieving an optimal guidewire placement with the ability to reduce surgical time and radiation exposure.

Percutaneous Scaphoid Fixation: Experience Value among Different Approaches.

Background Percutaneous scaphoid osteosynthesis is an attractive and increasingly popular option, as a treatment for acute scaphoid fractures in selected cases, and as an alternative to conservative treatment. The purpose of this study is to assess the radiographic positioning of the screw in percutaneous scaphoid fixation, taking into consideration the surgeons' experience, and the difference between volar and dorsal approaches. Methods We retrospectively assessed patients undergoing percutaneous scaphoid fixation from 2013 to 2019. Inclusion criteria are as follows: (1) scaphoid waist fractures (Herbert's B2), (2) a minimum of 18 years of age and a maximum of 55 years of age, (3) dominant hand, (4) manual work, (5) minimum follow-up time of 6 months, and (6) without associated lesions. Criteria for correct positioning are as follows: (1) on the axis or parallel to the scaphoid axis with a maximum deviation of 1.5 mm volar/dorsal, (2) without proximal/dorsal prominence, (3) correct scaphoid alignment/reduction, and (4) absence of threads in the fracture site. Radiographs were evaluated separately by a hand surgeon, a general orthopaedic surgeon, and an orthopaedic resident. Results With a total of 39 patients, a dorsal approach was performed in 10 patients and a palmar approach in 29 patients. We verified a very good interobserver reliability. The hand surgeon's team correctly positioned 15 (83.3%, 15/18), while the other team did 9 correctly (42.9%, 9/21). Comparing teams according to the approach used, the dorsal approach did not show a statistical difference, while the same was not true for the volar approach ( p < 0.05). Conclusion This points to a positive impact on the team's experience in the positioning of the screws, and therefore in the benefit of treatment by teams dedicated to the area, while daring to suggest that less-experienced surgeons should utilize the dorsal approach.

A 22-year-old chronic scaphoid non-union treated with arthroscopic percutaneous scaphoid fixation – A case report and review of literature

Scaphoid fractures are the most common fractures of the carpal bone. Most heal with adequate conservative treatment, but reports of non-union after conservative treatment have been up to 50%. Symptomatic non-union of a scaphoid fracture remains a common disabling problem. It is known that the scaphoid non-union will inevitably progress to the scaphoid non-union advance collapse over time. Surgical management of chronic non-union of scaphoid fracture includes vascularized bone grafting or non-vascularized bone grafting with or without internal fixation. A 36-year-old male presented with a hyperextension injury to the left little finger. An X-ray showed left little finger distal interphalangeal joint dislocation and an incidental 22-year-old chronic non-union scaphoid fracture. To date, incidental discovery of non-union is at the rate of 0.14%. The patient underwent arthroscopic non-vascularized bone grafting with internal fixation after the natural course of the condition was explained to him. He made a good recovery with a complete union of his scaphoid and resolution of his wrist pain. Our case describes the first case of arthroscopic repair of a chronic non-union scaphoid fracture of 22-year duration and demonstrates union of scaphoid fracture and resolution of symptoms can be achieved with good surgical fixation even extremely prolonged chronic non-union.

Correlation Between the Entry Point for Volar Percutaneous Scaphoid Fixation and Fracture Line

Correlation Between the Entry Point for Volar Percutaneous Scaphoid Fixation and Fracture Line

Robot-assisted percutaneous scaphoid fracture fixation: a report of ten patients.

This study reports the technique, efficacy and safety of robotic-assisted, computer-navigated, percutaneous fixation of scaphoid fractures. Ten males with acute undisplaced waist fractures underwent fixation with this method using a commercially available three-dimensional fluoroscopy unit and robotic navigation system. The mean total operative duration was 40 minutes, which comprised of a set-up time of 18 minutes and planning and surgical time of 22 minutes. All patients required only a single guidewire insertion attempt, and there were no screw protuberances or other complications. All fractures united at a mean of 8weeks. At a mean follow-up of 6.5months (range 6-8), the mean Mayo wrist score was 96, patient-rated wrist evaluation was 2, flexion-extension arc was 96% and grip strength was 91% of the contralateral side. We conclude from our patients that robotic-assisted percutaneous scaphoid fixation is feasible, safe and accurate, and is a satisfactory method for treating these injuries. Level of evidence: IV.

Scaphoid screw placement under minimal radiation exposure

BackgroundPercutaneous scaphoid fixation through either a volar or dorsal approach has the advantage of minor soft tissue damage compared with ORIF, and faster fracture union compared with conservative treatment. However, this technique demands highly intraoperative reliance on X-ray control, including increased radiation exposure and all associated side effects. PurposeTo test the possibility and efficacy of volar percutaneous scaphoid screw placement under minimalradiation exposure. MethodsThe sample included 20 hands (seven left, 13 right) from human adult cadavers. For this study, the utilised wrists were assumed to have non-displaced scaphoid fractures. Using a percutaneous approach, a 2-mm Kirschner wire (K-wire) was advanced to the distal pole of the scaphoid and placed in a 45° horizontal and vertical angle under monitoring with the C-arm. The K-wire was inserted blindly alongside the estimated length of the scaphoid. Following K-wire insertion, four X-rays were taken to depict K-wire positioning and to assess positioning alongside the axis of the scaphoid and K-wire protrusion. The rating scale comprised 1 (good), 2 (moderate) or 3 (poor). ResultsAll tested radiographic views were evaluated with a median of 2 points (moderate position) regardingplacement alongside the scaphoid axis. ConclusionOur results indicate that percutaneous scaphoid fixation with the guide wire placed in a 45° horizontal and vertical angle enables primary moderate positioning, which may lead to quicker adjustment to the ideal position and a decrease of radiation exposure.

Computer-assisted percutaneous scaphoid fixation: concepts and evolution.

Background The treatment for undisplaced scaphoid waist fractures has evolved from conventional cast immobilization to percutaneous screw insertion. Percutaneous fixation reduces some of the risks of open surgery, but can be technically demanding and carries the risk of radiation exposure. Recently, computer-assisted percutaneous scaphoid fixation (CAPSF) has been gaining interest. Materials and Methods Conventional percutaneous scaphoid fixation is performed under fluoroscopic guidance and involves insertion of a guide wire along the length of the scaphoid to facilitate placement of a cannulated screw. Adapting computer-assisted techniques for scaphoid fixation poses several unique challenges including patient tracking and registration. Results To date, five groups have successfully implemented systems for CAPSF. These systems have implemented wrist immobilization strategies to resolve the issue of patient tracking and have developed unique guidance techniques incorporating 2D fluoroscope, cone-beam CT, and ultrasound, to circumvent patient-based registration. Conclusions Computer-aided percutaneous pinning of scaphoid waist fractures can significantly reduce radiation exposure and has the potential to improve the accuracy of this procedure. This article reviews the rationale for, and the evolution of, CAPSF and describes the key principles of computer-assisted technology.

Investigating the performance of a wrist stabilization device for image-guided percutaneous scaphoid fixation

Conventional navigated surgery relies on placement of a reference marker on the anatomy of interest. However, placement of such a marker is not readily feasible in small anatomic regions such as the scaphoid bone of the wrist. This study aimed to develop an alternative mechanism for patient tracking that could be used to perform navigated percutaneous scaphoid fixation. A prototype wrist stabilization device was developed to immobilize the scaphoid relative to a reference marker attached to the device. A position measurement system and 3D fluoroscopy were used to study the accuracy and limitations of wrist stabilization during simulated clinical usage with a cadaver specimen. Reference markers mounted on the device were used to measure intra-device motion. Radiometallic beads implanted in the scaphoid were used to measure patient-device motion. Navigated planning and guidance of scaphoid fixation were performed in five cadaver and eight "ideally immobilized" plastic specimens. Postoperative 3D fluoroscopy was used to assess the accuracy of navigated drilling. The average intra-device motion was 1.9 mm during load application, which was elastically recovered upon release of the load. Scaphoid motion relative to the reference marker was predominately rotational with an average displacement of 1.25 mm and 2.0°. There was no significant difference in the accuracy of navigated drilling between the cadaver specimens and the ideally immobilized group. The prototype wrist stabilization device meets the criteria for effective wrist stabilization. This study provides insight concerning proper use of the device to minimize scaphoid displacement and design recommendations to improve immobilization.

Percutaneous fixation of acute scaphoid fractures

BackgroundFractures of the scaphoid are common in young men. Cast immobilization usually means a long period away from work and athletic activities. Early rigid fixation has been shown to promote a rapid functional recovery, but open reduction and internal fixation is technically demanding with the risk of damage to the radiocarpal ligaments, the scaphotrapezial joint, and the blood supply of the scaphoid.PurposeThe aim of this prospective case series study was to evaluate percutaneous scaphoid fixation for minimally displaced or undisplaced B1 or B2 fractures with respect to time to radiographic union and return to work.Patients and methodsWe report our technique and the results of a prospective study in 12 patients with acute scaphoid fractures. Patients were assessed functionally using the Mayo wrist score and by radiography. The patients were followed up until evidence of radiologic union (35-70 days), with an average of 55 days.ResultsTen patients had excellent score and two patients had good score according to the Mayo wrist score. According to patients' occupations, return to work ranged from 14 to 40 days. With respect to radiologic union, fractures were united at a mean of 55 days (35-70 days).ConclusionPercutaneous fixation for acute scaphoid fractures using Herbert screws is a satisfactory method and gives rapid functional recovery.

Volume rendering of three-dimensional fluoroscopic images for percutaneous scaphoid fixation: An in vitro study

Percutaneous fixation of scaphoid fractures offers potential advantages to cast treatment but can be difficult to perform with conventional two-dimensional imaging. This study aimed to evaluate the use of a novel navigation technique using volume-rendered images derived from intraoperative cone-beam computed tomography imaging, without the need for typical patient-based registration. Randomized in vitro trials in which a guidewire was inserted into a scaphoid model were conducted to compare volumetric navigation to conventional fluoroscopic C-arm (n = 24). Central wire placement, surface breach, procedure time, drilling attempts, and radiation exposure were compared between groups. Compared to conventional percutaneous insertion, navigation achieved equal or significantly better placement of the guidewire with fewer drilling attempts and less radiation exposure. On average, navigation took 74 s longer to perform than the conventional method, which was statistically significant but clinically irrelevant. This evaluation suggests that the technology is promising and may have many clinical benefits including improved fixation placement, fewer complications, and less radiation exposure. The intraoperative workflow is more efficient and eliminates the need for preoperative computed tomography, image segmentation, and patient-based registration typical of traditional navigated procedures.

Volume slicing of cone-beam computed tomography images for navigation of percutaneous scaphoid fixation

Percutaneous scaphoid fixation (PSF) is growing in popularity as a treatment option for non-displaced fractures. Success of this procedure demands high-precision screw placement, which can be difficult to achieve with standard 2D imaging. This study aimed to develop and test a system for computer-assisted navigation using volume slicing of 3D cone-beam computed tomography (CBCT). The navigated technique involved a distinctive workflow in which a 3D CBCT imager was calibrated preoperatively, circumventing the need for intraoperative patient-based registration. Intraoperatively, a 3D CBCT image was acquired for both preoperative planning and direct navigation using volume-rendered slices. An in vitro study was conducted to compare the navigated approach to two conventional fluoroscopic methods for volar PSF. The surgical goal was to insert a guide wire to maximize both length and central placement. There was no significant difference in the mean central placement of guide wire, although the variance in central placement was significantly lower using VS navigation (P < 0.01). The lengths of the drill paths were significantly longer for the VS-navigated group compared with one 2D group (P < 0.1). Each navigated trial required only one drilling attempt and resulted in less radiation exposure than conventional C-arm (P < 0.01). Volume-sliced navigation achieved a more repeatable and reliable central pin placement, with fewer drilling attempts than conventional 2D techniques. Volume-sliced navigation had a higher number of drill paths within the optimal zone maximizing both length of the path and depth from the surface.

Accuracy and Precision of Percutaneous Scaphoid Fixation using 3-D Volumetric Navigation: Level 2 Evidence

Accuracy and Precision of Percutaneous Scaphoid Fixation using 3-D Volumetric Navigation: Level 2 Evidence

Computer-Assisted Navigation of Volar Percutaneous Scaphoid Placement

To investigate a computer-assisted technique for retrograde insertion of a percutaneous scaphoid screw and compare insertion time, accuracy, and radiation exposure to the traditional technique. We hypothesize that computer-assisted navigation of volar percutaneous scaphoid screw placement would improve accuracy, require less time, and diminish radiation exposure when compared to the traditional technique. Ten matched pairs of cadaveric wrists were randomized to computer-assisted versus traditional volar percutaneous scaphoid screw placement. Time of the overall procedure, set-up time, time for ideal guide wire placement, and radiation time were recorded. Number of K-wire attempts was also recorded. Finally, accuracy of planned screw axis and actual screw axis were compared. Student's t-tests and rank sums were used to determine whether the differences in outcome variables between computer-assisted and traditional techniques was significant, with an alpha level of 0.05. Although the overall time of the 2 procedures and the set-up time were not different between the 2 groups, the time for placement of the K-wire was halved in the computer-assisted percutaneous scaphoid fixation group, and the number of K-wire attempts needed for accurate screw placement approached clinical significance. Although the radiation exposures for the individual components of set-up time and final check time were not different, the radiation exposures for global time of the procedure, K-wire placement, and screw placement were clinically significant. Computer-assisted navigation of volar percutaneous scaphoid screw placement takes no more time that traditional methods and significantly reduces the amount of radiation exposure to the patient. Although not statistically significant, the technique reduced the number of incorrect passes of the K-wire, requiring a single attempt in 4 of the 5 specimens.

Validation of a new surgical procedure for percutaneous scaphoid fixation using intra-operative ultrasound

A new technique for percutaneous fixation of non-displaced scaphoid fractures is described. The technique used pre-operative planning from computed tomography images, registration to intra-operatively acquired three-dimensional ultrasound images, and intra-operative guidance using an optical tracking system. Two stand-alone software applications were developed. The first one was used to determine the surgical plan pre-operatively and the second one was used to guide the surgeon during screw insertion. Laboratory validation of the technique included measurements of the inter-operator and intra-operator variability in the outcome of scaphoid fixation using the proposed procedure, and also included comparison of the performance of this procedure with the conventional percutaneous fixation technique using fluoroscopy. The results showed that the tight accuracy requirements of percutaneous scaphoid fixation were met and that the consistency was superior to the conventional technique.

A-0174 Optimising central screw placement in percutaneous scaphoid fixation: a ct study

A-0174 Optimising central screw placement in percutaneous scaphoid fixation: a ct study

Acute percutaneous scaphoid fixation using a non-cannulated Herbert screw.

Conservative treatment of fractures of the scaphoid often leads to an important physical and economic morbidity, especially in the young and active population. Acute percutaneous scaphoid fixation is a fast technique with minimal soft tissue damage, which allows immediate mobilisation without prolonged casting. We describe our operation technique in which we always use a non-cannulated Herbert screw. We place the screw freehand and always pass through the trapezium, a technique which is in our hands the best way to place the screw in the right position. It is not technically demanding, but has a considerable learning curve and requires a three-dimensional knowledge of the scaphoid. We reviewed the results of 44 patients treated in our centre between 1996 and 2001. Comparing with literature of percutaneous scaphoid fixation, we found similar results. Although in literature this technique is only indicated for minimally and non-displaced fractures of the waist (Herbert A2 and B2), we describe some good results with proximal pole fractures. Nevertheless we found that all cases of delayed and non-union occurred with this type of fracture.

Percutaneous scaphoid fixation: surgical technique volar approach with traction

Percutaneous scaphoid fixation: surgical technique volar approach with traction