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In early 2023, after three years of pandemic and delayed care, Ontario faced an overwhelming backlog of elective surgical procedures and unacceptable wait times. With hospitals experiencing historic health human resources shortages and critical capacity limitations, disruptive change was required. The Ontario government proposed to address these mounting access-to-care issues by paying for-profit healthcare clinics and surgi-centres to provide insured services, resulting in considerable controversy, much opposition, some praise, and many public protests. Previous experiences with for-profit independent health facilities had generated both complaints and documented problems with their operations. This article examines these concerns against the ethical principles of autonomy, beneficence, non-malfeasance, and justice. While much of this unease can be effectively addressed through collaboration and oversight, the complexity and costs involved in ensuring equity and quality may make it difficult for such facilities to maintain profitability.

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BACKGROUND: The nature of tasks required by hand surgeons require both forceful and repetitive maneuvers, thus subjecting these surgeons to the risk of musculoskeletal (MSK) injuries during their years in practice. AIM: To assess the prevalence, characteristics and impact of MSK disorders among hand surgeons. METHODS: A modified version of the physical discomfort survey was sent to surgeons who were members of the American Society for Surgery of the Hand via e-mail. The collected data were analyzed using descriptive statistics, one-way analysis of variance, and Fisher's exact test. P values of < 0.05 were considered statistically significant. RESULTS: Of the 578 respondents, 60.4% reported that they had sustained a work-related MSK injury, of which the most common diagnoses were lateral elbow epicondylitis (18.7%), low back pain (17.1%) and carpal tunnel syndrome (15.6%). Among those that reported an injury, 73.1 % required treatment and 29.2 % needed time off work as a direct result of their injury. The number of work-related injuries incurred by a surgeon increased significantly with increasing age (P < 0.003), increasing years in practice (P < 0.001) and higher case load (P < 0.05). CONCLUSION: To our knowledge this study is the first of its kind to assess MSK injuries sustained by Hand surgeons with a high incidence. These results should increase awareness on this aspect and fuel future studies directed at preventing these types of work-related injuries, thus minimizing the financial and psychological burden on these surgeons and the healthcare system.

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PURPOSE: To quantify the relative motion between the lunate and triquetrum during functional wrist movements and to examine the impact of wrist laxity on triquetral motion. METHODS: A digital database of wrist bone anatomy and carpal kinematics for 10 healthy volunteers in 10 different positions was used to study triquetral kinematics. The orientation of radiotriquetral (RT) and radiolunate rotation axes was compared during a variety of functional wrist movements, including radioulnar deviation (RUD) and flexion-extension (FE), and during a hammering task. The motion of the triquetrum relative to the radius during wrist RUD was compared with passive FE range of motion measurements (used as a surrogate measure for wrist laxity). RESULTS: The difference in the orientation of the radiolunate and RT rotation axes was less than 20° during most of the motions studied, except for radial deviation and for the first stage of the hammering task. During wrist RUD, the orientation of the RT rotation axis varied as a function of passive FE wrist range of motion. CONCLUSIONS: The suggestion that the lunate and triquetrum move together as an intercalated segment may be an oversimplification. We observed synchronous movement during some motions, but as the wrist entered RUD, the lunate and triquetrum no longer moved synchronously. These findings challenge the assumptions behind models describing the mechanical function of the carpals. CLINICAL RELEVANCE: Individual-specific differences in the amount of relative motion between the triquetrum and lunate may contribute to the variability in outcomes following lunotriquetral arthrodesis. Variation in triquetral motion patterns may also have an impact on the ability of the triquetrum to extend the lunate, affecting the development of carpal instability.

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BACKGROUND: Work-related injuries have gained recent attention, especially in the orthopaedic literature. As upper extremity orthopaedic surgical tasks require repetitive and constant maneuvers, these surgeons can be at increased risk of acquiring work-related musculoskeletal (MSK) disorders during their years in practice. AIM: To assess the prevalence, characteristics and impact of MSK disorders among upper extremity orthopaedic surgeons. METHODS: A modified version of the physical discomfort survey was sent to surgeons who were members of the American Shoulder and Elbow Surgeons and the Canadian shoulder and elbow society via e-mail. The collected data were analyzed using descriptive statistics, one-way analysis of variance, and Fisher's exact test. P values of < 0.05 were considered statistically significant. RESULTS: Of the 142 respondents, 90.8% were males and the majority were younger than 55 years old (65.5%). A work-related MSK injury was reported by 89.4% of respondents, of which the most common diagnoses were low back pain (26.1%) and lateral elbow epicondylitis (18.3%). Among those that reported an injury, 82.7% required treatment and 26% required time off work as a direct result of their injury. The need to undergo treatment due to the injury was associated with increased number of injuries (P < 0.01). Moreover, surgeons were more likely to require time off work when they had been in practice for > 21 years (P < 0.05). CONCLUSION: A high proportion of surgeons in our survey reported MSK injuries, with more than one quarter of surgeons reported requiring time off work due to an MSK injury. The high incidence of these disorders may place a financial and psychological burden on surgeons and affect their ability to provide patient care. Awareness of operative ergonomics, irrespective of surgical specialty may help to decrease or possibly prevent the occurrence of these disorders.

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PURPOSE: To determine the location of the rotation axis between the scaphoid and the lunate (SL-axis) during wrist flexion-extension (FE) and radial-ulnar deviation (RUD). METHODS: An established and publicly available digital database of wrist bone anatomy and carpal kinematics of 30 healthy volunteers (15 males and 15 females) in up to 8 different positions was used to study the SL-axis. Using the combinations of positions from wrist FE and RUD, the helical axis of motion of the scaphoid relative to the lunate was calculated for each trial in an anatomical coordinate system embedded in the lunate. The differences in location and orientation between each individual axis and the average axis were used to quantify variation in axis orientation. Variation in the axis location was computed as the distance from the closest point on the rotation axis to the centroid of the lunate. RESULTS: The variation in axis orientation of the rotation axis for wrist FE and RUD were 84.3° and 83.5°, respectively. The mean distances of each rotation axis from the centroid of the lunate for FE and RUD were 5.7 ± 3.2 mm, and 5.0 ± 3.6 mm, respectively. CONCLUSIONS: Based on the evaluation of this dataset, we demonstrated that the rotation axis of the scaphoid relative to the lunate is highly variable across subjects and positions during both FE and RUD motions. The range of locations and variation in axis orientations in this data set of 30 wrists shows that there is very likely no single location for the SL-axis. CLINICAL RELEVANCE: Scapholunate interosseous ligament reconstruction methods focused on re-creating a standard SL-axis may not restore what is more likely to be a variable anatomical axis and normal kinematics of the scaphoid and lunate.

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Previous two-dimensional (2D) studies have shown that there is a spectrum of carpal mechanics that varies between row-type motion and column-type motion as a function of wrist laxity. More recent three-dimensional (3D) studies have suggested instead that carpal bone motion is consistent across individuals. The purpose of this study was to use 3D methods to determine whether carpal kinematics differ between stiffer wrists and wrists with higher laxity. Wrist laxity was quantified using a goniometer in ten subjects by measuring passive wrist flexion-extension (FE) range of motion (ROM). In vivo kinematics of subjects' scaphoid and lunate with respect to the radius were computed from computed tomography (CT) volume images in wrist radial and ulnar deviation positions. Scaphoid and lunate motion was defined as "column-type" if the bones flexed and extended during wrist radial-ulnar deviation (RUD), and "row-type" if the bones radial-ulnar deviated during wrist RUD. We found that through wrist RUD, the scaphoid primarily flexed and extended, but the scaphoids of subjects with decreased laxity had a larger component of RUD (R2 = 0.48, P < 0.05). We also determined that the posture of the scaphoid in the neutral wrist position predicts wrist radial deviation (RD) ROM (R2 = 0.46, P < 0.05). These results suggest that ligament laxity plays a role in affecting carpal bone motion of the proximal row throughout radial and ulnar deviation motions; however, other factors such as bone position may also affect motion. By developing a better understanding of normal carpal kinematics and how they are affected, this will help physicians provide patient-specific approaches to different wrist pathologies.

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PURPOSE: An electromagnetic (EM) surgical tracking system was developed for orthopedic navigation. The reportedly poor accuracy of point-based EM navigation was improved by using anatomical impressions, which were EM-tracked personalized templates. Lines, rather than points, were consistently used for calibration and error evaluation. METHODS: Technical accuracy was tested using models derived from CT scans of ten cadaver shoulders. Tracked impressions were first designed, calibrated, and tested using lines as fiducial objects. Next, tracked impressions were tested against EM point-based navigation and optical point-based navigation, in environments that were either relatively empty or that included surgical instruments. Finally, a tracked impression was tested on a cadaver forearm in a simulated fracture-repair task. RESULTS: Calibration of anatomical impressions to EM tracking was highly accurate, with mean fiducial localization errors in positions of 0.3 mm and in angles of [Formula: see text]. Technical accuracy on physical shoulder models was also highly accurate; in an EM field with surgical instruments, the mean of target registration errors in positions was 2.2 mm and in angles was [Formula: see text]. Preclinical accuracy in a cadaver forearm in positions was 0.4 mm and in angles was [Formula: see text]. The technical accuracy was significantly better than point-based navigation, whether by EM tracking or by optical tracking. The preclinical accuracy was comparable to that achieved by point-based optical navigation. CONCLUSIONS: EM-tracked impressions-a hybrid of personalized templates and EM navigation-are a promising technology for orthopedic applications. The two technical contributions are the novel hybrid navigation and the consistent use of lines as fiducial objects, replacing traditional point-based computations. The accuracy improvement was attributed to the combination of physical surfaces and line directions in the processes of calibration and registration. The technical studies and preclinical trial suggest that EM-tracked impressions are an accurate, ergonomic innovation in image-guided orthopedic surgery.

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PURPOSE: An electromagnetic (EM) surgical tracking system was used for a functionally calibrated kinematic analysis of wrist motion. Circumduction motions were tested for differences in subject gender and for differences in the sense of the circumduction as clockwise or counter-clockwise motion. METHODS: Twenty subjects were instrumented for EM tracking. Flexion-extension motion was used to identify the functional axis. Subjects performed unconstrained wrist circumduction in a clockwise and counter-clockwise sense. Data were decomposed into orthogonal flexion-extension motions and radial-ulnar deviation motions. PCA was used to concisely represent motions. Nonparametric Wilcoxon tests were used to distinguish the groups. RESULTS: Flexion-extension motions were projected onto a direction axis with a root-mean-square error of [Formula: see text]. Using the first three principal components, there was no statistically significant difference in gender (all [Formula: see text]). For motion sense, radial-ulnar deviation distinguished the sense of circumduction in the first principal component ([Formula: see text]) and in the third principal component ([Formula: see text]); flexion-extension distinguished the sense in the second principal component ([Formula: see text]). CONCLUSION: The clockwise sense of circumduction could be distinguished by a multifactorial combination of components; there were no gender differences in this small population. These data constitute a baseline for normal wrist circumduction. The multifactorial PCA findings suggest that a higher-dimensional method, such as manifold analysis, may be a more concise way of representing circumduction in human joints.

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OBJECTIVE:  To assess the efficacy of a programme of supervised physiotherapy on the recovery of simple grade 1 and 2 ankle sprains. DESIGN:  A randomised controlled trial of 503 participants followed for six months. SETTING:  Participants were recruited from two tertiary acute care settings in Kingston, ON, Canada. PARTICIPANTS:  The broad inclusion criteria were patients aged ≥16 presenting for acute medical assessment and treatment of a simple grade 1 or 2 ankle sprain. Exclusions were patients with multiple injuries, other conditions limiting mobility, and ankle injuries that required immobilisation and those unable to accommodate the time intensive study protocol. INTERVENTION:  Participants received either usual care, consisting of written instructions regarding protection, rest, cryotherapy, compression, elevation, and graduated weight bearing activities, or usual care enhanced with a supervised programme of physiotherapy. MAIN OUTCOME MEASURES:  The primary outcome of efficacy was the proportion of participants reporting excellent recovery assessed with the foot and ankle outcome score (FAOS). Excellent recovery was defined as a score ≥450/500 at three months. A difference of at least 15% increase in the absolute proportion of participants with excellent recovery was deemed clinically important. Secondary analyses included the assessment of excellent recovery at one and six months; change from baseline using continuous scores at one, three, and six months; and clinical and biomechanical measures of ankle function, assessed at one, three, and six months. RESULTS:  The absolute proportion of patients achieving excellent recovery at three months was not significantly different between the physiotherapy (98/229, 43%) and usual care (79/214, 37%) arms (absolute difference 6%, 95% confidence interval -3% to 15%). The observed trend towards benefit with physiotherapy did not increase in the per protocol analysis and was in the opposite direction by six months. These trends remained similar and were never statistically or clinically important when the FAOS was analysed as a continuous change score. CONCLUSIONS:  In a general population of patients seeking hospital based acute care for simple ankle sprains, there is no evidence to support a clinically important improvement in outcome with the addition of supervised physiotherapy to usual care, as provided in this protocol.Trial registration ISRCTN 74033088 (www.isrctn.com/ISRCTN74033088).

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PURPOSE: Volar percutaneous scaphoid fracture fixation is conventionally performed under fluoroscopy-based guidance, where surgeons need to mentally determine a trajectory for the insertion of the screw and its depth based on a series of 2D projection images. In addition to challenges associated with mapping 2D information to a 3D space, the process involves exposure to ionizing radiation. Three-dimensional ultrasound has been suggested as an alternative imaging tool for this procedure; however, it has not yet been integrated into clinical routine since ultrasound only provides a limited view of the scaphoid and its surrounding anatomy. METHODS: We propose a registration of a statistical wrist shape + scale + pose model to a preoperative CT and intraoperative ultrasound to derive a patient-specific 3D model for guiding scaphoid fracture fixation. The registered model is then used to determine clinically important intervention parameters, including the screw length and the trajectory of screw insertion in the scaphoid bone. RESULTS: Feasibility experiments are performed using 13 cadaver wrists. In 10 out of 13 cases, the trajectory of screw suggested by the registered model meets all clinically important intervention parameters. Overall, an average 94 % of maximum allowable screw length is obtained based on the measurements from gold standard CT. Also, we obtained an average 92 % successful volar accessibility, which indicates that the trajectory is not obstructed by the surrounding trapezium bone. CONCLUSIONS: These promising results indicate that determining clinically important screw insertion parameters for scaphoid fracture fixation is feasible using 3D ultrasound imaging. This suggests the potential of this technology in replacing fluoroscopic guidance for this procedure in future applications.

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Segmentation of the wrist bones in CT images has been frequently used in different clinical applications including arthritis evaluation, bone age assessment and image-guided interventions. The major challenges include non-uniformity and spongy textures of the bone tissue as well as narrow inter-bone spaces. In this work, we propose an automatic wrist bone segmentation technique for CT images based on a statistical model that captures the shape and pose variations of the wrist joint across 60 example wrists at nine different wrist positions. To establish the correspondences across the training shapes at neutral positions, the wrist bone surfaces are jointly aligned using a group-wise registration framework based on a Gaussian Mixture Model. Principal component analysis is then used to determine the major modes of shape variations. The variations in poses not only across the population but also across different wrist positions are incorporated in two pose models. An intra-subject pose model is developed by utilizing the similarity transforms at all wrist positions across the population. Further, an inter-subject pose model is used to model the pose variations across different wrist positions. For segmentation of the wrist bones in CT images, the developed model is registered to the edge point cloud extracted from the CT volume through an expectation maximization based probabilistic approach. Residual registration errors are corrected by application of a non-rigid registration technique. We validate the proposed segmentation method by registering the wrist model to a total of 66 unseen CT volumes of average voxel size of 0.38 mm. We report a mean surface distance error of 0.33 mm and a mean Jaccard index of 0.86.

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PURPOSE: Image-guided interventions that use preoperative 3D computed tomography (CT) models are limited by the preoperative segmentation time 3D image and collection of intraoperative registration data. Intraoperative CT imaging can be ergonomically efficient in a direct navigation system if the imaging device is accurately calibrated. A mobile-gantry CT scanner offers improved patient safety but presents technical challenges beyond those of a conventional scanner. The goal was to calibrate an optoelectronic navigation system to mobile-gantry CT with millimeter-level accuracy. METHODS: A custom calibration device was designed and manufactured. The calibrator contained optoelectronic markers for navigation reference and radio-opaque markers for CT reference. Calibrations were performed with a ceiling-mounted optoelectronic camera and with a portable camera, and then verified for accuracy. RESULTS: The component fiducial registration errors were extremely small, being 0.36 mm, with standard deviation of 0.16 mm, for the ceiling-mounted camera, and 0.05 mm, with standard deviation of 0.01 mm, for the portable camera. The net target registration error, measured as RMS deviation, was 1.58 mm for the ceiling-mounted camera and 0.73 mm for the portable camera. CONCLUSIONS: High-accuracy calibration of the mobile-gantry CT scanner was possible from a single preoperative CT image. A ceiling-mounted optoelectronic camera, which is ergonomically preferable, marginally met the accuracy criteria. The portable camera, which is in widespread use for conventional navigated surgery, had deep sub-millimeter error. This study demonstrates that high accuracy is achievable and offers a system developer options to trade off accuracy and user convenience in direct surgical navigation.

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PURPOSE: The scaphoid bone is the most frequently fractured bone in the wrist. When fracture fixation is indicated, a screw is inserted into the bone either in an open surgical procedure or percutaneously under fluoroscopic guidance. Due to the complex geometry of the wrist, fracture fixation is a challenging task. Fluoroscopic guidance exposes both the patient and the physician to ionizing radiation. Ultrasound-based guidance has been suggested as a real-time, radiation-free alternative. The main challenge of using ultrasound is the difficulty in interpreting the images due to the low contrast and noisy nature of the data. METHODS: We propose a bone enhancement method that exploits local spectrum features of the ultrasound image. These features are utilized to design a set of quadrature band-pass filters and subsequently estimate the local phase symmetry, where high symmetry is expected at the bone locations. We incorporate the shadow information below the bone surfaces to further enhance the bone responses. The extracted bone surfaces are then used to register a statistical wrist model to ultrasound volumes, allowing the localization and interpretation of the scaphoid bone in the volumes. RESULTS: Feasibility experiments were performed using phantom and in vivo data. For phantoms, we obtain a surface distance error 1.08 mm and an angular deviation from the main axis of the scaphoid bone smaller than 5°, which are better compared to previously presented approaches. CONCLUSION: The results are promising for further development of a surgical guidance system to enable accurate anatomy localization for guiding percutaneous scaphoid fracture fixations.

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BACKGROUND: Bilateral and simultaneous lower extremity amputations unrelated to diabetes and peripheral vascular disease are uncommon, although they may be necessary in patients with severe blast injuries. Such amputations, however, usually are performed in patients who are able to understand and consent to the treatment. CASE DESCRIPTION: We present the case of a 29-year-old woman who experienced drug-induced psychosis and underwent substantial hypothermic injuries; most notably, irreversible frostbite injuries to both lower extremities, leading to dry and mummified gangrene. As a result of her psychiatric illness, fluctuating catatonic state, and lack of insight into her clinical condition, she was deemed incapable of making decisions regarding her medical care and her mother was made substitute decision maker. The orthopaedic service was consulted regarding possible surgical treatment of her gangrenous feet that were stable and aseptic after limb preservation efforts (including hyperbaric oxygen) had been tried without success. They recommended close clinical monitoring and continued psychiatric treatment. The family, including the substitute decision maker, citing the patient's best interest, rejected the recommendations of the surgical team and demanded immediate surgical transtibial amputation of both lower legs. LITERATURE REVIEW: To our knowledge, such a unique case has not been reported. CLINICAL RELEVANCE: We examined the decision-making process, the difficulties of caring for such a patient, and the ethical issues that arose.

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BACKGROUND: Preoperative planning and intraoperative navigation technologies have each been shown separately to be beneficial for optimizing screw and baseplate positioning in reverse shoulder arthroplasty (RSA) but to date have not been combined. This study describes development of a system for performing computer-assisted RSA glenoid baseplate and screw placement, including preoperative planning, intraoperative navigation, and postoperative evaluation, and compares this system with a conventional approach. MATERIALS AND METHODS: We used a custom-designed system allowing computed tomography (CT)-based preoperative planning, intraoperative navigation, and postoperative evaluation. Five orthopedic surgeons defined common preoperative plans on 3-dimensional CT reconstructed cadaveric shoulders. Each surgeon performed 3 computer-assisted and 3 conventional simulated procedures. The 3-dimensional CT reconstructed postoperative units were digitally matched to the preoperative model for evaluation of entry points, end points, and angulations of screws and baseplate. Values were used to find accuracy and precision of the 2 groups with respect to the defined placement. Statistical analysis was performed by t tests (α = .05). RESULTS: Comparison of the groups revealed no difference in accuracy or precision of screws or baseplate entry points (P > .05). Accuracy and precision were improved with use of navigation for end points and angulations of 3 screws (P < .05). Accuracy of the inferior screw showed a trend of improvement with navigation (P > .05). Navigated baseplate end point precision was improved (P < .05), with a trend toward improved accuracy (P > .05). CONCLUSION: We conclude that CT-based preoperative planning and intraoperative navigation allow improved accuracy and precision for screw placement and precision for baseplate positioning with respect to a predefined placement compared with conventional techniques in RSA.

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PURPOSE: Electromagnetic (EM) tracking of instruments within a clinical setting is notorious for fluctuating measurement performance. Position location measurement uncertainty of an EM system was characterized in various environments, including control, clinical, cone beam computed tomography (CBCT), and CT scanner environments. Static and dynamic effects of CBCT and CT scanning on EM tracking were evaluated. METHODS: Two guidance devices were designed to solely translate or rotate the sensor in a non-interfering fit to decouple pose-dependent tracking uncertainties. These devices were mounted on a base to allow consistent and repeatable tests when changing environments. Using this method, position and orientation measurement accuracies, precision, and 95 % confidence intervals were assessed. RESULTS: The tracking performance varied significantly as a function of the environment-especially within the CBCT and CT scanners-and sensor pose. In fact, at a fixed sensor position in the clinical environment, the measurement error varied from 0.2 to 2.2 mm depending on sensor orientations. Improved accuracies were observed along the vertical axis of the field generator. Calibration of the measurements improved tracking performance in the CT environment by 50-85 %. CONCLUSION: EM tracking can provide effective assistance to surgeons or interventional radiologists during procedures performed in a clinical or CBCT environment. Applications in the CT scanner demand precalibration to provide acceptable performance.

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Although cadaveric specimens that have been fresh-frozen then thawed are considered the gold standard for biomechanics research, because they most closely represent in vivo tissues, potential problems include a relatively short useful time-span and risk of infection. A recently reported new method of phenol-based "soft" embalming has been found to preserve tissues in a fresh-like state over an extended period of time and simultaneously reduced infection risks. This study presents radio-ulnar deviation end-range data from 4 soft-embalmed and refrigerated human cadaveric forearm specimens over 12 months. All end-range comparisons were found to be statistically equivalent to within a clinically acceptable range of ±5 degrees of radio-ulnar deviation with a 95% con. dence measure of p < 0.01 in every case. These soft-embalmed specimens provide promising results for further use in biomechanical studies.

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PURPOSE: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

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PURPOSE: This article presents the results of a multiuser, randomized laboratory trial comparing the accuracy and precision of image-based navigation against individualized guides for distal radius osteotomy (DRO). METHODS: Six surgeons each performed four DROs using image-based navigation and four DROs using individualized guides in a laboratory setting with plastic phantom replicas of radii from patients who had received DRO as treatment for radial deformity. Time required and correction errors of ulnar variance, radial inclination, and volar tilt were measured. RESULTS: There were no statistically significant differences in the average correction errors. There was a statistically significant difference in the standard deviation of ulnar variance error (2.0 mm for navigation vs. 0.6 mm for guides). There was a statistically significant difference in the standard deviation of radial inclination error ([Formula: see text] for navigation vs. [Formula: see text] for guides). There were statistically significant differences in the times required (705 s for navigation vs. 214 s for guides) and their standard deviations (144 s for navigation vs. 98 s for guides). CONCLUSIONS: Compared to navigated DRO, individualized guides were easier to use, faster, and produced more precise correction of ulnar variance and radial inclination. The combination of true three-dimensional planning, ease of use, and accurate and precise corrective guidance makes the individualized guide technique a promising approach for performing corrective osteotomy of the distal radius.

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