Objectives. The purpose of this study was to evaluate the impact of multi-radius (MR, n=20) versus gradually reducing radius (GR, n=18) knee design on the kinematics and kinetics of the knee during level ground walking one year after total knee arthroplasty. Materials and Methods. Thirty-eight knees with end-stage knee osteoarthritis were examined before and one year after total knee arthroplasty. The groups consisted of subjects who had undergone total knee arthroplasty with a representative MR designed implant (B Braun-Aesculap Vega. ®. Knee System) and a representative GR designed implant (Depuy Attune. ®. Knee System) (Figure 1). The kinematic and kinetic parameters of knee varus angle, first peak knee adduction moment, sagittal plane knee excursion and extensor moment were evaluated during gait, as well as the spatiotemporal gait outcomes of walking speed, stride length, cadence, step length, the percentage of stance phase. Comparisons of preoperative and postoperative outcomes were done by the paired t-test. Independent t-test was also done to compare the postoperative outcomes of MR designed implant and GR designed implant. Results. In spatiotemporal parameters of GR implant group, there was an increase in walking speed, stride length and cadence (all p<0.05) and no change in step length and the percentage of stance phase postoperatively. GR implant group showed large reductions in varus angle and adduction moment (all p<0.001), a significant increase in extensor moment (p=0.01), and a small reduction in sagittal plane excursion (p=0.04) after surgery. In comparison of two groups at one year after surgery, there were no significant differences of all spatiotemporal, kinematic and kinetic parameters between two groups except varus angle. GR implant group showed more reduction in varus angle than MR implant group (p=0.01). Conclusions. Total knee arthroplasty performed with gradually reducing radius knee design reduces frontal plane loading patterns of knee varus angle and adduction moment and provided improvement in spatiotemporal parameters. Post-operatively there were no statistical differences between the MR implant group and the GR implant group in any of the kinematic and kinetic measures except knee varus angle during level ground walking

Long femoral nails for neck of femur fractures and prophylactic fixation have a risk of anterior cortex perforation. Previous studies have demonstrated the radius of curvature (ROC) of a femoral nail influencing the finishing point of a nail and the risk of anterior cortex perforation. This study aims to calculate a patients femoral ROC using preoperative XR and CT and therefore nail finishing position. We conducted a retrospective study review of patients with long femoral cephalomedullary nailing for proximal femur fractures (OTA/AO 31(A) and OTA/AO 32) or impending pathological fractures at a level 1 trauma centre between January 1, 2015 and December 31, 2020 with both full length lateral X-ray and CT imaging. Femoral ROC was calculated on both imaging modalities. Outcomes measured including nail finishing position, anterior cortex encroachment and impingement. The mean femoral ROC was 1026mm on CT and 1244mm on XR. CT femoral ROC strongly correlated with nail finishing point with a spearmans coefficient of 0.77. Additionally, femurs with a ROC <1000mm were associated with a higher risk of anterior encroachment (OR 6.12) and femurs with a ROC <900mm were associated with a higher risk of anterior cortex impingement (OR 6.47). To our knowledge this is the first study to compare a measured femoral ROC to nail finishing position. The use of CT to measure femoral ROC and to a lesser extent XR was able to predict both nail finishing position and risk of anterior cortex encroachment. Preoperative XRs and CTs were able to identify patients with a small femoral ROC. This predicted patients at risk of anterior cortex impingement, anterior cortex encroachment and nail finishing position. We may be able to select femoral nails that resemble the native femoral ROC and mitigate the risk of anterior cortex perforation

The radius has a sagittal and coronal bow. Fractures are often treated with volar anterior plating. However, the sagittal bow is often overlooked when plating. This study looks at radial morphology and the effect of plating the proximal radius, with straight plates then contoured plates bowed in the sagittal plane. We report our findings and their effect on forearm rotation. Morphology was investigated using fourteen radii. Attention was made to the proximal shaft of the radius and its sagittal bow, from this 6, 7 and 8 hole plates were contoured to fit this bow. A simple transverse fracture was then made at the apex of this bow. Supination and pronation was then compared when plating with a straight plate and a contoured plate. Ten cadavers had the ulna plating at the same level. The effect on rotation of fractures plated in the distal third shaft was also measured. A significant reduction in rotation was found, when a proximal radius fracture was plated with straight plate compared to a contoured plate: 10.8, 12.8, 21.7 degrees (p<0.05 for 6, 7, 8 hole plates). Forearm rotation was decreased further when a longer plate was used. Ulna or distal shaft plating did not reduce rotation. This study has shown a significant sagittal bow of the proximal shaft of the radius. Plating this with contoured plates in the sagittal plane improves rotation when compared to straight plates. Additional ulna plating is not a source of reduced forearm rotation

Fractures of the distal radius are common, and form a considerable proportion of the trauma workload. We conducted a study to examine the patterns of injury and treatment for adult patients presenting with distal radius fractures to a major trauma centre serving an urban population. We undertook a retrospective cohort study to identify all patients treated at our major trauma centre for a distal radius fracture between 1 June 2018 and 1 May 2021. We reviewed the medical records and imaging for each patient to examine patterns of injury and treatment. We undertook a binomial logistic regression to produce a predictive model for operative fixation or inpatient admission. Overall, 571 fractures of the distal radius were treated at our centre during the study period. A total of 146 (26%) patients required an inpatient admission, and 385 surgical procedures for fractures of the distal radius were recorded between June 2018 and May 2021. The most common mechanism of injury was a fall from a height of one metre or less. Of the total fractures, 59% (n = 337) were treated nonoperatively, and of those patients treated with surgery, locked anterior-plate fixation was the preferred technique (79%; n = 180). The epidemiology of distal radius fractures treated at our major trauma centre replicated the classical bimodal distribution described in the literature. Patient age, open fractures, and fracture classification were factors correlated with the decision to treat the fracture operatively. While most fractures were

Aims of study. To assess and compare the functional, radiological and cosmetic results as well as patient satisfaction in patients treated with the IMN Device Vs Volar Locking Plate. Method. All patients who presented to our institution with extra articular distal radius fractures and met the inclusion criteria were invited to take part in the study. The patients were randomly allocated to two groups, those who underwent intramedullary (IMN) distal radius fixation using the Sanoma Wrx Distal radius nail and those who underwent fixation using a volar locking plate. The patients were then followed up at 2 weeks, 6 weeks, 3 months, 6 months and 1 year. The radiological parameters, ie radial height, inclination and tilt were compared as well as the functional outcomes by means of DASH score. The range of motion of the wrist was compared as well as the scar size. Complications were reviewed. Results. We present our early results. Currently we have included 9 patients in the IMN group and 7 patients in the volar plate group with follow-ups longer than 3 months. Results show smaller scars (2.5 vs 6.7cm), comparable flexion and extension (40 vs 40 and 45 vs 40), slight improvements in pronation and supination (80 vs 75 and 85 vs 80) in the IMN compared to the volar plate. Radial and ulnar deviation is comparable. The radiological parameters showed slight improvements in the radial height (2.5 vs 2.2 mm), inclination (3.6 vs 3.2 degrees) and tilt 13,7 vs 12 degrees) with the IMN. Dash scores will be compared at 6 months. Conclusion. Intra medullary nailing of the distal radius seems to compare to volar plating in terms of radiological parameters and rotational stability but has the added benefit of early range of motion, minimal invasive technique, less post op pain and less complications such as tendon irritation. NO DISCLOSURES

Premature growth arrests are an infrequent, yet a significant complication of physeal fractures of the distal radius in children and adolescents. Through early diagnosis, it is possible to prevent clinical repercussions of the anatomical and biomechanical alterations of the wrist. Their true incidence has not been well established, and there exists no consensual systematic monitoring plan for minimising its impacts. The main objective was to evaluate the prevalence of growth arrests after a physeal distal radius fracture. The secondary objective was to identify risk factors in order to better guide clinicians for a systematic follow-up. All patients seen between 2014–2016 in a tertiary orthopaedic clinic were retrospectively reviewed. Inclusion criteria were (one) a physeal fracture of the distal radius (two) adequate clinical/radiological follow-up. Descriptive, Chi-square and binary logistic regression analyses were carried out using SPSS software. One hundred ninety patients (mean age: 12 ± 2.8 years) fulfilled the inclusion criteria. Forty percent (n=76) of the fractures were treated by closed reduction. Premature growth arrest was seen in 6.8% (n=13) and diagnosed at a mean of 10 months post trauma. The logistic regression showed that the initial translation percentage (>30%) (p 25) (p increase the risk of growth arrest. After adjusting for concomitant ipsilateral ulnar injuries, a positive association between physeal complications and fracture manipulation was detected (76.9%, p=0.03). A non-significant trend between premature growth arrest and associated ulnar injury was observed (p=0.054). No association was identified for trauma velocity, fracture type, gender and age, and growth complications. A prevalence of 6.8% of growth arrest was found after a physeal fracture of the distal radius. Fractures presenting with an initial coronal translation > 30% and/or angulation > 25 from normal, as well as those treated by manipulation, have been shown to be at risk for a premature growth arrest of the distal radius. This study highlights the importance of a systematic follow-up after a physeal fracture of the distal radius especially for patients with a more displaced fracture who had a closed reduction performed. An optimal follow-up period should be over 10 months to optimize the detection of growth arrest and treat it promptly, thereby minimizing negative clinical consequences

The aim of this study was to determine the floor and ceiling effects for both the QuickDASH and PRWE following a fracture of the distal radius. Secondary aims were to determine the degree to which patients with a floor or ceiling effect felt that their wrist was ‘normal’, and if there were patient factors associated with achieving a floor or ceiling effect. A retrospective cohort study of patients sustaining a distal radius fracture and managed at the study centre during a single year was undertaken. Outcome measures included the QuickDASH, the PRWE, EuroQol-5 Dimension-3 Levels (EQ-5D-3L), and the normal wrist score. There were 526 patients with a mean age of 65yrs (20–95) and 421 (77%) were female. Most patients were managed non-operatively (73%, n=385). The mean follow-up was 4.8yrs (4.3–5.5). A ceiling effect was observed for both the QuickDASH (22.3%) and PRWE (28.5%). When defined to be within the minimum clinical important difference of the best available score, the ceiling effect increased to 62.8% for the QuickDASH and 60% for the PRWE. Patients that achieved a ceiling score for the QuickDASH and PRWE subjectively felt their wrist was only 91% and 92% normal, respectively. On logistic regression analysis, a dominant hand injury and better health-related quality of life were the common factors associated with achieving a ceiling score for both the QuickDASH and PRWE (all p<0.05). The QuickDASH and PRWE demonstrate ceiling effects when used to assess the outcome of fractures of the distal radius. Patients achieving ceiling scores did not consider their wrist to be ‘normal’. Future patient-reported outcome assessment tools for fractures of the distal radius should aim to limit the ceiling effect, especially for individuals or groups that are more likely to achieve a ceiling score

Extensor tendon ruptures have been reported in up to 8.8% of patients after volar plating and long screws have been implicated. The dihedral dorsal surface of the distal radius hinders accurate screw length determination using standard radiographic views (lateral; pronation and supination). A ‘dorsal tangential’ view has recently been described, but has not been validated. To validate this view, we mounted a plate-instrumented sawbone onto a jig. Radiographs at different angles were reviewed independently by 11 individuals. Skyline views clearly demonstrated all screw tips, whereas only 69% of screw tips were identifiable on standard views. With screws 2mm proud of the dorsal surface, skyline views detected 67% of long screws (sensitivity). The best of the standard views achieved only 11% sensitivity. At 4mm long, skyline sensitivity was 85%, compared with 25% for standard views. At 6mm long, 100% of long screws were detected on skylines, but only 50% of 8mm long screws were detected by standard views. Inter and intra-observer variability was 0.97 (p=0.005). For dorsal screw length determination of the distal radius, the skyline view is superior to standard views. It is simple to perform and its introduction should reduce the incidence of volar plate-related extensor tendon rupture

Distal radius fractures are the most common upper extremity fracture. The incidence is significantly higher in elderly females with osteoporotic bone. When surgery is indicated, volar locking plates (VLPs) allow for rigid fixation particularly in comminuted fractures with poor bone quality. Although numerous studies have shown the importance of plate placement to avoid soft tissue complications associated with volar plate fixation, there has been little evidence on the anatomic fit of current VLPs. Moreover, the effect of gender differences in distal radius morphology on anatomic fitting of VLPs has not been studied. The aim of this study was to evaluate the gender difference in distal radius morphology and the accuracy of the fit of a current VLP to CT-based distal radius models. Segmented CT models of ten female (mean age, 89 ± 5 years), and ten male (mean age, 86 ± 4 years) cadaveric wrists were obtained. Micro-CT models of the DePuy-Synthes 4-hole extra-articular (EA) and 8-hole volar column (VC) distal radius VLPs were created. A 3D visualization software was used to simulate appropriate plate placement on to the distal radius models by a fellowship-trained hand surgeon. Volar cortical angles (VCA) of the medial, middle and lateral portion of the distal radius were measured and compared between genders. The accuracy of the fit of the two VLP designs were quantified using the percentage of the watershed line (WSL) overlapped by the plate (WSL overlap), the distance between the WSL and the most distal aspect of the posterior plate (prominence distance) and the percentage of contact between the plate and bone. There were statistically significant gender differences in medial, middle and lateral VCAs (p=.003 medial, p=.0001 middle, p=.002 lateral). VCA ranged from 28° to 36° in females and from 38° to 45° in males. The WSL overlap did not show statistically significant gender differences (male: 5.9%, female: 13.6%, p=.174). However, the difference in prominence distance between different genders approached statistical significance (male: 3.5mm, female: 2.6mm, p=.087). Contact mapping between the plate and bone did not demonstrate a perfect contact in any of our specimens. Thus, contact measurements were categorized into 0.1mm, 0.2mm, and 0.3mm threshold contacts. There were no statistically significant gender differences in any of the threshold categories (0.1mm: p=.84, 0.2mm: p=.97, 0.3mm: p=.99). Our results confirm that there are gender differences in distal radius morphology. Current plate designs incorporate a VCA of 25° which does not match the native VCA of the distal radius in males or females. Although the difference in prominence distance approached statistical significance, there were no statistically significant gender differences in the WSL overlap or the contact threshold values. This lack of statistical significance may be related to the small sample size. This study proposes novel methods of assessing the anatomic fit of current VLPs in a 3D CT-based model that may be used in future studies with a larger sample size. Moreover, this study demonstrated the importance of considering gender differences in distal radius morphology in the design of future generations of implants

Distal radius fractures are the most common upper extremity injury, and are increasingly being treated surgically with pre-contoured volar-locking plates. These plates are favored for their low-profile template while allowing for rigid anatomic fixation of distal radius fractures. The geometry of the distal radius is extremely complex, and little evidence within the medical literature suggests that current implant designs are anatomically accurate. The main objective of this study is to determine if anatomic alignment of the distal radii corresponds accurately with modern volar-locking plate designs. Additionally, this study will examine sex-linked differences in morphology of the distal radius. Segmented CT models of ten female cadaver (mean age, 88.7 ± 4.57 years, range, 82 – 97) arms, and ten male cadaver (mean age, 86 ± 3.59 years, range, 81 – 91) arms were created. Micro CT models were obtained for the DePuy Synthes 2.4mm Extra-articular (EA) Volar Distal Radius Plate (4-hole and 5-hole head), and 2.4mm LCP Volar Column (VC) Distal Radius Plate (8-hole and 9-hole head). Plates were placed onto the distal radii models in a 3D visualization software by a fellowship-trained orthopaedic hand surgeon. The percent contact, volar cortical angle (VCA), border and overlap of the watershed line (WSL) were measured. Both sexes showed an increase in the average VCA measure from medial to lateral columns which was statistically significant. Female VCA ranged from 28 – 36 degrees, and 38 – 45 degrees for males. WSL overlap ranged from 0 – 34.7629% for all specimens without any statistical significance. The average border distance for females was 2.58571 mm, compared to 3.52411 mm for males, with EA plates having a larger border than VC plates. The border distances had statistically significant differences between the plate types, and was approaching significance between sexes. Lastly, a maximum percent contact of 21.966 % was observed in specimen F4 at a 0.3 mm threshold. No statistical significance between plate or sex populations was observed. This study investigated the incoherency between the volar cortical angle of the distal radius, and the pre-contoured angle of volar locking plates. It was hypothesized that if the VCA measures between plate and bone were unequal then there would be an increase in watershed line overlap, and decrease in percent contact between the surfaces. Our results agreed with literature, indicating that the VCA of bone was larger than that of the EA and VC pre-contoured plates examined in this study. With distal radius fracture incidences and prevalence on the rise for elderly female patients, it is a necessity that volar locking plates be re-designed to factor in anatomical features of individual patients with a particular focus on sex differences. New designs should focus on providing smaller head sizes that are more accurately tailored to the natural contours of the volar distal radius. It is recommended that future studies incorporate expertise from multiple surgeons to diversify and further understand plate placement strategies

The treatment of unstable distal radius fractures remains controversial. Volar locking plates provide stable fixation using the fixed angle device principle. More recently this technique has gained increasing popularity with several reports demonstrating good results. We present our experience from the first 259 patients performed at this institution. Method: Local Ethics Committee approval was obtained prior to the onset of the study. Theatre records and implant forms were used to recruit all patients in whom a Distal Volar Radius (DVR) Plate, (DePuy, Leeds, United Kingdom) was used for an unstable distal radius fracture between August 2005 and February 2008. Surgery was performed either by a consultant, or a specialist registrar. Two hundred and fifty nine consecutive patients were identified. Six patients had bilateral distal radius fractures. Patient records were reviewed, and each patient contacted via a postal questionnaire and Patient-Rated Wrist Evaluation (PRWE). Other outcome measures included return to work and complication rate. Results: Of the 259 patients 160 responses were received, response rate 62%. The mean follow up was 30.8 months, (Range 18–48). The mean age of the patients was 57.3 years (Range 16–93). The mean inpatient stay was 1.6 days, (mode 1 day). The median PRWE was 3; (range 0–83) and the mode was 0. Ninety four of the patients had a PRWE of ≤5. Seventy one out of 78 patients (91%) returned to the same job. The mean return to work was 40.6 days (SD37.5). There were 13 minor complications in total (7.8%). Six patients had extensor tendon irritation, of which two patients required extensor tendon reconstruction. One further patient had a spontaneous EPL rupture which was not associated with prominent metal work. Four (2.4%) patients had median nerve symptoms postoperatively. Two patients subsequently required carpal tunnel decompression, the other two settled spontaneously. Two (1.2%), patients developed Complex Regional Pain Syndrome. One patient developed a minor superficial wound infection. In all, 9 (5.4%) patients had removal of their metalwork, 6 for tendon irritation, 2 for wrist stiffness (one which was positioned too distally) and 1 for pin penetration into the joint. Discussion: Our results show that the DVR plate can be used reliably with good results and an early return to high levels of function. This is the largest series to date of the use of this distal volar locking plate

Perioperative glucocorticoids have been used as a successful non-opioid analgesic adjunct for various orthopaedic procedures. Here we describe an ongoing randomized control trial assessing the efficacy of a post-operative methylprednisolone taper course on immediate post-operative pain and function following surgical distal radius fixation. We hypothesize that a post-operative methylprednisolone taper course following distal radius fracture fixation will lead to improved patient pain and function. This study is a randomized control trial (NCT03661645) of a group of patients treated surgically for distal radius fractures. Patients were randomly assigned at the time of surgery to receive intraoperative dexamethasone only or intraoperative dexamethasone followed by a 6-day oral methylprednisolone (Medrol) taper course. All patients received the same standardized perioperative pain management protocol. A pain journal was used to record visual analog pain scores (VAS-pain), VAS-nausea, and number of opioid tablets consumed during the first 7 post-operative days (POD). Patients were seen at 2-weeks, 6-weeks, and 12-weeks post-operatively for clinical evaluation and collection of patient reported outcomes (Disabilities of the Arm, Shoulder and Hand Score [qDASH]). Differences in categorical variables were assessed with χ2 or Fischer's exact tests. T-tests or Mann-Whitney-U tests were used to compare continuous data. Forty-three patients were enrolled from October 2018 to October 2019. 20 patients have been assigned to the control group and 23 patients have been assigned to the treatment group. There were no differences in age (p=0.7259), Body Mass Index (p=0.361), race (p=0.5605), smoking status (p=0.0844), or pre-operative narcotic use (p=0.2276) between cohorts. 83.7% (n=36) of patients were female and the median age was 56.9 years. No differences were seen in pre-operative qDASH (p=0.2359) or pre-operative PRWE (p=0.2329) between groups. In the 7 days following surgery, patients in the control group took an average of 16.3 (±12.02) opioid tablets, while those in the treatment group took an average of 8.71 (±7.61) tablets (p=0.0270). We see that significant difference in Opioid consumption is formed at postoperative day two between the two groups with patients in the control group taking. Patient pain scores decreased uniformly in both groups to post-operative day 7. Patient pain was not statistically from POD0 to POD2 (p=0.0662 to 0.2923). However, from POD4 to POD7 patients receiving the methylprednisolone taper course reported decreased pain (p=0.0021 to 0.0497). There was no difference in qDASH score improvement at 6 or 12 weeks. Additionally, no differences were seen for wrist motion improvement at 6 or 12 weeks. A methylprednisolone taper course shows promise in reducing acute pain in the immediate post-operative period following distal radius fixation. Furthermore, although no statistically significant reductions in post-operative opioid utilization were noted, current trends may become statistically significant as the study continues. No improvements were seen in wrist motion or qDASH and continued enrollment of patients in this clinical trial will further elucidate the role of methylprednisolone for these outcomes

Clinically significant proximal junctional kyphosis (PJK) occurs in 20% of children treated with posterior distraction-based growth friendly surgery. In an effort to identify modifiable risk factors, it has been theorized biomechanically that low radius of curvature (ROC) implants (i.e., more curved rods) may increase post-operative thoracic kyphosis, and thus may pose a higher risk of developing PJK. We sought to test the hypothesis that EOS patients treated with low ROC (more curved rods) distraction-based treatment will have a greater risk of developing PJK as compared to those treated with high ROC (straighter) implants. This is a retrospective review of prospectively collected data obtained from a multi-centre EOS database on children treated with rib-based distraction with minimum 2-year follow-up. Variables of interest included: implant ROC at index (220 mm or 500 mm), patient age, pre-operative scoliosis, pre-operative kyphosis, and scoliosis etiology. In the literature, PJK has been defined as clinically significant if revision surgery with superior extension of the upper instrumented vertebrae was performed. In 148 scoliosis patients, there was a higher risk of clinically significant PJK with low ROC (more curved) rods (OR: 2.6 (95%CI 1.09-5.99), χ2 (1, n=148) = 4.8, p = 0.03). Patients had a mean pre-operative age of 5.3 years (4.6y 220 mm vs 6.2y 500 mm, p = 0.002). A logistic regression model was created with age as a confounding variable, but it was determined to be not significant (p = 0.6). Scoliosis etiologies included 52 neuromuscular, 52 congenital, 27 idiopathic, 17 syndromic with no significant differences in PJK risk between etiologies (p = 0.07). Overall, patients had pre-op scoliosis of 69° (67° 220mm vs 72° 500mm, p = 0.2), and kyphosis of 48° (45° 220mm vs 51° 500mm, p = 0.1). The change in thoracic kyphosis pre-operatively to final follow up (mean 4.0 ± 0.2 years) was higher in patients treated with 220 mm implants compared to 500 mm implants (220 mm: 7.5 ± 2.6° vs 500 mm: −4.0 ± 3.0°, p = 0.004). Use of low ROC (more curved) posterior distraction implants is associated with a significantly greater increase in thoracic kyphosis which likely led to a higher risk of developing clinically-significant PJK in EOS patients

Purpose: Treatment of radial head fractures of Mason Type II and III involving the neck of the radius is still controversial, especially in the presence of comminution. ORIF often gives unsatisfactory results because of the difficulty in restoring the head-neck off-set and the radial head inclination relative to its neck. In these cases radial head replacement may be indicated ; however, there are no long-term studies on complications and survival of the implant. Recently precontoured plates for the proximal radius has been introduced but no trials have determined whether they are able to restore the normal anatomy of the radius. The latter is still partially unknown because no studies have analyzed the morphology of posterolateral aspect of radial head and neck (“safe zone”). Our study was aimed at:. determining the possible presence of anatomical variations of the safe-zone and. analyzing the anatomical congruence of precontoured plates to this zone. Material and Methods: Measurements, performed on 44 cadaver dry radii of adults, included: length of the radius, diameters and height of the radial head, and height and diameter of the neck of the radius. The radius of bending of the safe zone was also calculated. Results: The morphological evaluation of the “safe zone” of the radius revealed 3 different morphological types of this zone:. (flat) (25 %),. (slightly concave) (63,6 %) and. (markedly concave) (11,4 %),. Adherence of a precoundered plate (Acumed) to the bone surface of the safe zone was performed independently by three of us, and the gap between plate and bone was measured. Plate adaptability was good in Type B, scarce in Type C and absent in Type A. Conclusion: In conclusion, we identified 3 different morphologies of the safe zone, not previously described, and we found that the precountered plates now available can ensure a good restoration of anatomy only in the half of the human radii

Previously, we have described a novel, computer assisted technique of osteotomy for distal radius malunion. Laboratory and clinical results demonstrate excellent realignment of the articular fragment, but incomplete correction of the radioulnar convergence and loss of radial bow. This study describes an innovation whereby both the proximal and distal fragments of the malunited radius are manipulated in 3D relative to an external template. Two case studies demonstrate the improve restoration of anatomy with this technique. The purpose of this study was to develop a method of computer-assisted planning and image guided surgery to restore the normal bow to the malunited radius. Manipulation of a virtual model of a distal radius malunion can only restore the full anatomical bow to the radius if both the distal and proximal fragments are corrected to match a normal template. This is a novel method of restoring normal anatomy in which both fragments of a malunited bone are corrected relative to an external normal template. A previously developed CT-based research software system for conducting computer-assisted distal radius osteotomy allowed three-dimensional manipulation of the distal fragment only, to restore the alignment of the distal articular surface. Results of the first six cases demonstrated that this system did not fully correct the convergence of the radius and ulna with persistent loss of radial bow, although it does provide excellent realignment of the articular fragment. The system was modified to include the ability to manipulate the proximal fragment of the radius. This fragment is rotated and translated to match an external reference template derived from a mirror image CT surface mesh of the opposite forearm. Results of two case studies are evaluated, demonstrating the computer models and post-operative radiographs confirming improved restoration of radial anatomy compared to the previous system

Proximal Radius – Fractures of the proximal radius in children account for slightly more than 1% of all children’s fractures, represent 5 to 10% of all elbow fractures and accounts for 5% of all fractures involving the growth plate. The average age in the literature is 10 years (4 to 16 years) with no difference between boys and girls. The anatomical aspects should be emphasized for the comprehension of this fracture: 1) the radial head of the child only starts to ossify at age 5 so it is very rare to have a fracture before this age since all the head is cartilaginous and therefore more resistant to trauma. At the same time it makes more difficult the diagnosis because of the absence of ossification of the epiphysis. 2) There is a valgus angulation of 12.5° between the radial head and the shaft of the radius in the AP plan and an anterior angulation of 3° on the lateral plane that should not be misinterpreted as fractures. 3) The radial head is intrarticular in a similar way like the femoral head and trauma to this region may lead to AVN as a result of damage to the vascular supply of the epiphysis. 4) The proximal radioulnar joint has a very intimate continuity contributing to exact congruence of the articular surfaces. The axis of rotation lies directly in the center of the radial neck. Any deviation of the epiphysis over the neck has a major reflect over the axis of rotation causing a “cam” effect when the radial head rotates with loss of pronosupination. The mechanism of injury responsible for this injury result from a fall on the outstretched upper extremity in which the elbow is extended and a valgus force is applied to the elbow joint. In more rare cases it result from direct pressure to the radial head during dislocation of the elbow. There are different classifications mostly based on the anatomical lesion or degree of deformity. Wilkins divides this fracture in two major groups: Group I (valgus fracture) subdivided in three types: type A – the Salter-Harris type I and II, type B – Salter-Harris type IV and type C – fractures involving only the proximal radial metaphysis and Group II (fractures associated with elbow dislocation) subdivided in two types: type D – reduction injuries and type E – dislocation injuries. O’Brien divides the common valgus injury in three types according to the degree of angulation between the radial head and the axis of the radius: Type I (0 to 30° angulation) Type II (between 30° and 60°) and Type III (more than 60°). The clinical symptoms may vary according to the magnitude of the injury. The child will mostly complaint of pain and tenderness on the lateral side of the joint. In young children pain may first be referred to the wrist. The pain usually increases with pronosupination and extension of the elbow. The diagnosis relies mostly on the x-ray view (AP and lateral) and the fracture will be easily visualized in either film. In the cases where the fracture line is superimposed over the ulna an oblique view will be necessary. In the young child, whereas the epiphysis is still not ossified, an ultrasound may be helpful differentiating the position of the radial head. An arthrogram may also be of benefit especially during the process of reduction to check the accuracy of the treatment. The prognosis of this lesion depends on several factors. A poor result can be expected if the fracture is associated with other injuries such as elbow dislocation and ulna or medial epicondylar fractures. A residual tilt of the radial head, provided is not superior to 30°, is more tolerable than a translocation of the radial head superior to 4mm. Age is also an important factor since the older the child the less remodeling it will have. The treatment has also an important role in the prognosis of this injury since it is unanimous acceptable that an open reduction is associated with poor results. Therefore the treatment of a young child with an isolated minimal displaced fracture-separation of the proximal radius (less than 30°) should be a simple long arm cast. In a more displaced fracture (more than 30° of tilt) a closed reduction should be performed under general anesthesia as suggested by Patterson. If the maneuver is not successful other attempts should be made with lateral pin compression applied directly to the radial head as suggested by Pesudo or an indirect reduction by an intramedullary kirschner wire as suggested by Metaizeau. Open reduction should be only reserved for dislocated Grade IV Salter-Harris type fractures, incarcerated radial head or in the presence of failure of closed treatment. The incidence of complications especially if associated with a dislocation of the elbow or other fractures can be high. The most common are loss of motion, radial head overgrowth usually with no clinical significance, notching of the radial neck and premature physeal closure. Avascular necrosis of the radial head is most commonly associated with open reduction. Distal Radius – It is the most common fracture separation in children and represent 46% of all fractures involving the growth plate. A fracture of the ulna is associated in 6 to 11% of the injuries. The average age is 12 years with a minimum of 7 and a maximum of 16 years. Although this high incidence it is very uncommon subsequent growth disturbance. The usual mechanism of injury is similar to the proximal radius injury and result from a fall on the outstretched upper extremity with the wrist hyperextended. This type of injury is classified by the Salter-Harris classification for physeal fractures and the most commons are the types I and II. The clinical symptoms vary from mild tenderness over the fracture site to a noticeable deformity most often with the apex volar. Attention should be given to the possibility of vascular and neural injury associated, mostly from the time of the acute deformation, and the diagnosis is made by x-ray view (AP and lateral) with the fracture well visualized. The prognosis is in general good since even in the presence of a markedly displaced fracture it can be expected a remarkably remodeling even in an older child. Treatment in a nondisplaced fracture only requires a below elbow cast for 4 weeks. In a displaced fracture a closed reduction should be performed under hematoma block or general anesthesia (in a young child). The reduction is stable most of the times in a plaster with the wrist in slight flexion. The incidence of complications is very rare

Purpose: We compare the accuracy and precision of patient-specific plastic guides versus computer-assisted navigation for distal radius osteotomy (DRO). We hypothesize that guides would provide similar accuracy and precision compared to computer-assisted surgery, and that they would be faster to use than navigated surgery. Method: We used CT scans, computer models, and planned corrections of radii from seven patients who had previously received computer-assisted DRO. The planned correction included the locations and directions of the screw holes for the fixation plate on the intact deformed radius. Using computer-assisted technique, the surgeon drills the holes for the fixation plate using computer navigation before performing the osteotomy; after cutting the radius, the plate is fixated to the distal radius, and the distal radius is distracted until the holes in the proximal radius align with the holes of the fixation plate. A patient-specific guide can be manufactured that fits on the intact deformed radius to guide the drilling of the screw holes. The guide is designed so that it mates exactly with the dorsal surface of the radius. Each guide was designed using custom software and manufactured in ABS plastic using a 3D printer. The surgeon places the guide on the radius and uses a metal drill sleeve in each guide hole to guide the drilling of the plate screw holes. We manufactured urethane plastic phantoms of the seven deformed radii. Our laboratory experiment had six surgeons each perform four computer-assisted and four patient-specific guide procedures on the phantom radii; the specimen and type of guidance were randomly chosen. The time from the start of the procedure to when the shaping of the distal radius was completed was recorded; we did not record the time required to cut and fixate the radius because this time does not depend on the type of guidance used. The plated phantoms were assessed for errors in ulnar variance, radial inclination, and volar tilt as compared to the planned correction. Results: The results for the computer-assisted procedures were: ulnar variance error (−0.2 +/ − 2.0 mm), radial inclination error (−0.9 +/ − 6.1 deg), volar tilt error (−0.9 +/ − 1.9 deg). The results for the customized jig procedures were: ulnar variance error (−0.7 +/ − 0.6 mm), radial inclination error (−1.0 +/ − 1.4 deg), volar tilt error (−0.4 +/ − 2.2 deg). There were no significant differences detected in the means of the measurements (significance level 0.05) using the two-sample t-test. Significant differences were detected in the variances of the ulnar variance and radial inclination errors (significance level 0.05) using Levene’s test. It took (705 +/ − 144 sec) to perform the computer-assisted procedures and (214 +/ − 98 sec) to perform the customized guide procedures. The differences between the means and variances were statistically significant. Conclusion: Patient-specific guides are as accurate, more precise, and require less time than computer-assisted navigation for DRO

Purpose. Intra-articular fractures of the distal radius are common injuries. Their pathogenesis involves a complex combination of forces, including ligament tension, bony compression and shearing, leading to injury patterns that challenge the treating surgeon. The contribution of the radiocarpal and radioulnar ligaments to articular fracture location has not previously been described. Computed tomography (CT) scanning is an important method of evaluating intra-articular distal radius fractures, revealing details missed on plain radiographs and influencing treatment plans. Methods. We retrospectively reviewed CT scans of acute intra-articular distal radius fractures performed in one institution from June 2001 to June 2008. Forty- five of 145 scans were deemed unsuitable due to poor quality or presence of internal fixation in the distal radius, leaving 100 fractures for review. Fracture line locations were mapped to a standardised distal radius model, and statistically analysed in their relationship to ligament attachment zones. Results. Distal radius articular fracture lines are significantly less likely to occur in the regions of ligament attachment. Conversely, fracture lines are more likely to occur in the gaps between major ligament attachments. Conclusion. Articular fracture locations in the distal radius are significantly related to radiocarpal and radioulnar ligament attachments. This may aid treating surgeons in understanding the personality of a fracture and the role of ligamentotaxis in fracture reduction

Introduction: Osteonecrosis is a devastating disease which can affect multiple joints including the distal radius. Although there are a number of studies that have reported the clinical outcomes of patients treated for osteonecrosis of the hip, knee, shoulder, and other locations, there are no known studies that have evaluated the outcome of patients who have this disease in the distal radius. The purpose of this study was to assess the characteristics of atraumatic, symptomatic osteonecrosis of the distal radius. In addition, based on reports that have shown the safe and effective use of core decompressions to treat early stages of osteonecrosis in other joints, we assessed whether this treatment modality also would provide pain relief and delay progression of the disease in the distal radius. Methods: A review of 434 osteonecrosis patient records from the past 7 years in our prospectively collected database identified 4 patients (6 wrists) who had the disease in the distal radius. Two of these patients also had the disease in the ulna. All 4 patients were women, and their mean age was 46 years (range, 37 to 52 years). Clinical and radiographic outcomes were assessed at a mean of 39 months (range, 12 to 84) following treatment with core decompression. The clinical evaluations were conducted using the Michigan Hand Outcomes Questionnaire (MHQ). The reported pre-operative MHQ component scores for function, completion of everyday activities, pain, completion of work activities, overall appearance of the hands, and patient satisfaction were compared to the results of the MHQ at final follow-up. Radiographic success of the core decompressions was based on whether there was any progression in the stage of the disease. Results: The most common risk factor for this cohort of patients was corticosteroids with 3 of the 4 patients having reported prior use. Other risk factors included alcohol consumption on a regular basis (n = 2), tobacco abuse (n = 2), blood dyscrasia (n = 2), and systemic lupus erythematosus (n = 1). Additionally, all 4 patients had multifocal osteonecrosis (affecting at least four separate anatomic sites. Overall, the patients reported a mean improvement in MHQ score (from 65% to 84%). Stratified by category, satisfaction improved from 64% to 88%, overall hand function increased from 64% to 81%, and pain was reduced from 60% to 25%, for pre- and post-operative values, respectively. One patient (2 wrists) required additional core decompressions in each wrist at one year following surgery but reported sustained improvement in her MHQ for both wrists at two years following her second core decompressions. There were no complications associated with the core decompressions, and there was no radiographic progression in the stage of the disease in any of the cases. Discussion: Osteonecrosis of the distal radius is rarely found in patients with this disease (< 1%). It can be found in patients with osteonecrosis of other joints who have a symptomatic wrist and may have more than one risk factor. It can be readily diagnosed with x-rays and/or MRI. The results of the present study suggest that core decompression is a safe and effective treatment modality for symptomatic osteonecrosis of the wrist at the distal radius and/or ulna. Although the level of improvement in MHQ varied for each case, all patients reported reduced pain and improved function at final follow-up without any apparent complications. Based on these results, we recommend the use of core decompressions to alleviate the symptoms and to possibly delay the progression of distal radius osteonecrosis

After a fracture of the distal radius, the bone segments may heal in a suboptimal position. This condition may lead to a reduced hand function, pain and finally osteoarthritis, sometimes requiring corrective surgery. The contralateral unaffected radius is often used as a reference in planning of a corrective osteotomy procedure of a malunited distal radius. In the conventional procedure, radiographs of both the affected radius and the contralateral radius have been used for planning. The 2D nature of radiographs renders them sub-optimal for planning due to overprojection of anatomical structures. Therefore, computer-assisted 3D planning techniques have been developed recently based on CT images of both forearms. The accuracy of using the contralateral forearm for CT based 3D planning the surgery of the affected arm and the optimal strategy for planning have not been studied thoroughly. To estimate the accuracy of the planned repositioning using the contralateral forearm we investigated bilateral symmetry of corresponding radii and ulnae using 3-dimensional imaging techniques. A total of 20 healthy volunteers without previous wrist injury underwent a volumetric computed tomography scan of both forearms. The left radius and ulna were segmented to create virtual 3 dimensional models of these bones. We selected a distal part and a larger proximal part from these bones and matched them with a mirrored CT-image of the contralateral side. This allowed estimation of the accuracy by calculation of relative displacements (Δx, Δy, Δz) and rotations (Δψx, Δψy, Δψz) required to align the left bone with the right bone segments as a reference. We also investigated the relationship between longitudinal length differences in radius and ulna and utilised this relationship to arrive at an optimal planning of the length of the affected radius after surgery. Relative differences in displacement and orientation parameters after planning based on the contralateral radius were (Δx, Δy, Δz): −0.81±1.22 mm, −0.01±0.64 mm, and 2.63±2.03 mm; and (Δψx, Δψy, Δψz): 0.13°±1.00°, −0.60°±1.35°, and 0.53°±5.00°. The same parameters for the ulna were (Δx,Δy, Δz): −0.22±0.82 mm, 0.52±0.99 mm, 2.08±2.33 mm; and (Δψx, Δψy, Δψz): −0.56°±0.96°, −0.71°±1.51°, and −2.61°±5.58°. The results also point out that there is a strong linear relationship between absolute length differences (Δz) of the radius and ulna among the individuals. Since we observed substantial length difference of the longitudinal bone axes of both forearms in healthy individuals, including the length difference of the adjacent forearm bones in the planning turned out to be useful in improving length correction in computer-assisted planning of radius or ulna osteotomies. The improved planning markedly reduces length positioning variability, (from 2.9± 2.1 mm to 1.5 ± 0.6 mm). We expect this approach to be valuable for 3-D planning of a corrective distal radius osteotomy. Awareness of the level of bilateral symmetry is important in reconstructive surgery procedures when the contralateral unaffected side is used as a reference for planning and evaluation. Bilateral asymmetry may introduce length errors into this type of preoperative planning that can be reduced by taking into account the concomitant ulnae asymmetry