Three-dimensional cortical and trabecular bone microstructure of the proximal ulna.

INTRODUCTION: The three-dimensional (3D) microstructure of the cortical and trabecular bone of the proximal ulna has not yet been described by means of high-resolution 3D imaging. An improved characterization can provide a better understanding of their relative contribution to resist impact load. The aim of this study is to describe the proximal ulna bone microstructure using micro-computed tomography (micro-CT) and relate it to gross morphology and function. MATERIALS AND METHODS: Five dry cadaveric human ulnae were scanned by micro-CT (17 µm/voxel, isotropic). Both qualitative and quantitative assessments were performed on sagittal image stacks. The cortical thickness of the trochlear notch and the trabecular bone microstructure were measured in the olecranon, bare area and coronoid. RESULTS: Groups of trabecular struts starting in the bare area, spanning towards the anterior and posterior side of the proximal ulna, were observed; within the coronoid, the trabeculae were orthogonal to the joint surface. Consistently among the ulnae, the coronoid showed the highest cortical thickness (1.66 ± 0.59 mm, p = 0.04) and the olecranon the lowest (0.33 ± 0.06 mm, p = 0.04). The bare area exhibited the highest bone volume fraction (BV/TV = 43.7 ± 22.4%), trabecular thickness (Tb.Th = 0.40 ± 0.09 mm) and lowest structure model index (SMI = - 0.28 ± 2.20, indicating plate-like structure), compared to the other regions (p = 0.04). CONCLUSIONS: Our microstructural results suggest that the bare area is the region where most of the loading of the proximal ulna is concentrated, whereas the coronoid, together with its anteromedial facet, is the most important bony stabilizer of the elbow joint. Studying the proximal ulna bone microstructure helps understanding its possible everyday mechanical loading conditions and potential fractures. LEVEL OF EVIDENCE: N.A.

Regional differences in the three-dimensional bone microstructure of the radial head: implications for observed fracture patterns.

INTRODUCTION: A characterization of the internal bone microstructure of the radial head could provide a better understanding of commonly occurring fracture patterns frequently involving the (antero)lateral quadrant, for which a clear explanation is still lacking. The aim of this study is to describe the radial head bone microstructure using micro-computed tomography (micro-CT) and to relate it to gross morphology, function and possible fracture patterns. MATERIALS AND METHODS: Dry cadaveric human radii were scanned by micro-CT (17 µm/pixel, isotropic). The trabecular bone microstructure was quantified on axial image stacks in four quadrants: the anterolateral (AL), posterolateral (PL), posteromedial (PM) and anteromedial (AM) quadrant. RESULTS: The AL and PL quadrants displayed the significantly lowest bone volume fraction and trabecular number (BV/TV range 12.3-25.1%, Tb.N range 0.73-1.16 mm-1) and highest trabecular separation (Tb.Sp range 0.59-0.82 mm), compared to the PM and AM quadrants (BV/TV range 19.9-36.9%, Tb.N range 0.96-1.61 mm-1, Tb.Sp range 0.45-0.74 mm) (p = 0.03). CONCLUSIONS: Our microstructural results suggest that the lateral side is the "weaker side", exhibiting lower bone volume faction, less trabeculae and higher trabecular separation, compared to the medial side. As the forearm is pronated during most falls, the underlying bone microstructure could explain commonly observed fracture patterns of the radial head, particularly more often involving the AL quadrant. If screw fixation in radial head fractures is considered, surgeons should take advantage of the "stronger" bone microstructure of the medial side of the radial head, should the fracture line allow this.

Outcomes after revision total elbow arthroplasty: a systematic review.

BACKGROUND: Although revision arthroplasty surgery is a frequently used treatment for failed total elbow arthroplasty (TEA), published results are conflicting. The aim of this systematic review was to provide an overview of the outcomes of revision TEA surgery. METHODS: A systematic literature search was performed in major databases to find articles relating to outcomes after revision of TEA. Two reviewers independently screened the articles for inclusion, and a third reviewer screened them before final inclusion. RESULTS: Twenty-one articles containing 532 cases were included. The mean age at revision was 61 years. The mean interval between primary and revision arthroplasty was 77 months, and the average follow-up period was 65 months. Different types of prostheses were included, with 69% of the revision prostheses having linked designs and 31% having unlinked designs. The visual analog scale score, Mayo Elbow Performance Score, Oxford Elbow Score, and range of motion improved significantly after revision surgery. Complications were reported in 232 of 532 cases (44%), leading to reoperations in 22%. After revision with linked prostheses, the Mayo Elbow Performance Score, range of flexion-extension, and pronation improved significantly more than with unlinked designs. CONCLUSION: Improved functional outcomes can be expected after revision TEA, but the complication rate remains high. Revision TEA should still be considered a salvage procedure for failed TEA. Linked designs for revision TEA result in better outcomes than unlinked designs in the midterm follow-up.

Surgical approaches for total elbow arthroplasties using data from the Dutch Arthroplasty Register.

BACKGROUND: Total elbow arthroplasty (TEA) is a relatively infrequently performed procedure. Therefore, nationwide databases help to provide more insight into factors that might influence implant survival, for example, the surgical approach used. Using data from the Dutch Arthroplasty Register, we aimed to reveal whether high-volume centers use different approaches than low-volume centers and whether the approach is implant specific. METHODS: Using data from 2014 to 2017, we compared the surgical approaches used for high- vs. low-volume centers, as well as for the 2 most frequently used types of TEA, by use of χ2 tests. RESULTS: We analyzed 276 procedures. In 2016 and 2017, when posterior approaches were further specified, the triceps-on approach was used most frequently in the high-volume center (27 of 42 procedures, 64%) and the triceps-flap approach was used most often in the low-volume centers (48 of 84 procedures, 57%) (P < .001). For the 2 most frequently used types of TEA, the Coonrad-Morrey and Latitude EV arthroplasties, the surgical approaches did not differ. When the high-volume center was compared with the low-volume centers, implant choice differed, with the Coonrad-Morrey arthroplasty being most often used in the high-volume center and the Latitude EV arthroplasty, in the low-volume centers. CONCLUSION: The posterior triceps-flap approach was the most frequently used surgical approach in primary TEA in the Netherlands, yet the triceps-on approach was used more often in the high-volume center. The surgical approaches did not differ between the 2 most frequently used types of TEA in the Netherlands.

Use and outcome of 1,220 primary total elbow arthroplasties from the Australian Orthopaedic Association National Joint Arthroplasty Replacement Registry 2008-2018.

Background and purpose - The Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) was analyzed to determine trends in use of primary total elbow arthroplasty (TEA), the types of prostheses used, primary diagnoses, reasons for and types of revision, and whether the primary diagnosis or prosthesis design influenced the revision rate.Patients and methods - During 2008-2018, 1,220 primary TEA procedures were reported of which 140 TEAs were revised. Kaplan-Meier estimates of survivorship were used to describe the time to first revision and hazard ratios (HR) from Cox proportional hazard models, adjusted for age and sex, were used to compare revision rates.Results - The annual number of TEAs performed remained constant. The 3 most common diagnoses for primary TEA were fracture/dislocation (trauma) (36%), osteoarthritis (OA) (34%), and rheumatoid arthritis (RA) (26%). The cumulative percentage revision for all TEAs undertaken for any reason was 10%, 15%, and 19% at 3, 6, and 9 years. TEAs undertaken for OA had a higher revision rate compared with TEAs for trauma (HR = 1.8, 95% CI 1.1-3.0) and RA (HR = 2.0, CI 1.3-3.1). The Coonrad-Morrey (50%), Latitude (30%), Nexel (10%), and Discovery (9%) were the most used prosthesis designs. There was no difference in revision rates when these 4 designs were compared. The most common reasons for revision were infection (35%) and aseptic loosening (34%).Interpretation - The indications for primary and revision TEA in Australia are similar to those reported for other registries. Revision for trauma is lower than previously reported.

Continuous passive motion and physical therapy (CPM) versus physical therapy (PT) versus delayed physical therapy (DPT) after surgical release for elbow contractures; a study protocol for a prospective randomized controlled trial.

BACKGROUND: The elbow is prone to stiffness after trauma. To regain functional elbow motion several conservative- and surgical treatment options are available. Conservative treatment includes physical therapy, intra-articular injections with corticosteroids and a static progressive or dynamic splinting program. If conservative treatment fails, an operative release of the posttraumatic stiff elbow is often performed. The best Evidence-Based rehabilitation protocol for patients after an operative release is unknown to date and differs per surgeon, hospital and country. Options include early- or delayed motion supervised by a physical therapist, immediate continuous passive motion (CPM), (night) splinting and a static progressive or dynamic splinting program. METHODS/DESIGN: The SET-Study (Stiff Elbow Trial) is a single-centre, prospective, randomized controlled trial. The primary objective of this study is to compare the active Range of Motion (ROM) (flexion arc and rotational arc) twelve months after surgery between three groups. The first group will receive in-hospital CPM in combination with early motion Physical Therapy (PT) supervised by a physical therapist, the second group will receive only in-hospital early motion PT supervised by a physical therapist and the third group will receive outpatient supervised PT from postoperative day seven till ten. Secondary outcome measures will be Patient Reported Outcome Measures (PROMs) including the Mayo Elbow Performance Score (MEPS), the Oxford Elbow Score (OES), the quick Disabilities of Arm, Shoulder and Hand (qDASH) score, Visual Analogue pain Scale in rest and activity (VAS), Pain Catastrophizing Scale (PCS), the Short Form (SF)-36, the Centre for Epidemiological Studies Depression Scale Revised (CESD-R) and the Work Rehabilitation Questionnaire (WORQ) for the upper limb. DISCUSSION: A successful completion of this trial will provide evidence on the best rehabilitation protocol in order to (re)gain optimal motion after surgical release of the stiff elbow. TRIAL REGISTRATION: The trial is registered at the Dutch Trial Register: NTR6067 , 31-8-2016.

Clinical and radiographic outcome of revision surgery of total elbow prosthesis: midterm results in 19 cases.

BACKGROUND: The aim of this study is to report on the midterm outcomes and complications of revision surgery of total elbow arthroplasty. METHODS: All patients who had undergone total elbow arthroplasty revision surgery between 2009 and 2014 with semiconstrained total elbow prostheses were prospectively enrolled in the study. Records were reviewed for demographic data; baseline measurements; and several follow-up assessments including the Mayo Elbow Performance Score (MEPS), visual analog scale (VAS) score for pain, Oxford Elbow Score, range of motion, satisfaction, and radiographs. RESULTS: A total of 19 revision arthroplasties were included. At a mean follow-up of 57 months, there had been 1 rerevision and 2 removals. One patient was excluded from follow-up because of confounding comorbidity. At last follow-up, MEPS values and VAS pain scores both improved (P < .01). The rate of combined good and excellent results on the MEPS was 53%. The mean VAS scores for pain at rest and with activity were 2 and 4, respectively. Fair results for the Oxford Elbow Score were reported, with a mean score of 28 points. Range of motion improved to an average flexion-extension arc of 108° (P < .01), and the pronation-supination arc improved to an average of 123° (P < .01). All elbows were stable at last follow-up (P < .01). Radiographs showed nonprogressive osteolysis around the prosthesis in 3 cases (19%) and suspicion of loosening in 1 (6%). In 11 patients postoperative complications occurred. Of 15 patients, 13 (87%) were satisfied with the result of the revision procedure. CONCLUSION: Revision of total elbow prostheses leads to satisfactory results, less pain, and better elbow function. This procedure is related to a relatively high complication rate.

Clinical and radiographic outcome of revision surgery of radial head prostheses: midterm results in 16 patients.

BACKGROUND: Little is known about revision surgery of radial head arthroplasty. The aim of this study was to report on the clinical and radiographic outcome of revision arthroplasty of the elbow with a bipolar metallic radial head prosthesis. METHODS: Between 2006 and 2013, we used either a press-fit or cemented RHS bipolar radial head prosthesis for revision surgery of radial head arthroplasty in 16 patients. Patients were prospectively enrolled in the study. Differences in outcome parameters before and after revision surgery were compared. RESULTS: At a mean follow-up of 75 months (range, 36-116 months), none of the revised radial head prostheses needed a second revision. None of the stems showed radiographic signs of loosening. In 1 patient the head was dissociated from the prosthesis. The average flexion-extension arc was 127° (range, 105°-140°), and the average pronation-supination arc was 138° (range, 90°-160°). Stability scores improved after revision surgery, resulting in 13 stable elbows (P = .01). In 8 patients the Oxford Elbow Score was between 37 and 48 points. The percentage of patients with either good or excellent results according to the Mayo Elbow Performance Score was 63%. The mean score on the EQ-5D (EuroQol Five Dimensions) was 80 (range, 63-100), and the visual analog scale scores both for pain at rest and for pain with activity improved to 3 (range, 0-9) and 4 (range, 0-9), respectively (P < .001). All but 1 patient was satisfied with the results of the revision procedure. CONCLUSION: The clinical and radiographic outcomes of revision surgery of a radial head prostheses are favorable.

Management of the failed radial head arthroplasty.

Primary radial head arthroplasty (RHA) produces good or excellent results in approximately 85% of patients. However, complications are not uncommon and have been described in up to 23% of cases.The number of RHA is increasing, and consequently the absolute number of complications is expected to rise as well. The decision on whether to revise or remove the prosthesis seems more likely to depend on the preference of the surgeon or the hospital, rather than on objectifying problems with the prosthesis.The current article presents an algorithm for the work-up and treatment of most complications that can occur following RHA.Five subgroups of problems were identified: osteoarthritis, stiffness, instability, infection and implant-related issues.In short, the preferred treatment depends mainly on the chondral condition and stability of the elbow joint. Cite this article: EFORT Open Rev 2020;5:398-407. DOI: 10.1302/2058-5241.5.190055.

Arthroscopic localization of the ulnar nerve behind the medial capsule is unreliable.

PURPOSE: Ulnar nerve injury is the most common neurologic complication of elbow arthroscopy. The purpose of this cadaveric study was to quantify the ability of surgeons to locate the ulnar nerve behind the posteromedial capsule during elbow arthroscopy using sole arthroscopic vision. METHODS: Twenty-one surgeons were asked to pin the ulnar nerve at the medial gutter and the posteromedial compartment using arthroscopic visualization of the medial capsule only. Pinning of the ulnar nerve was performed from extra-articular. Then, the cadaveric specimens were dissected and the shortest distances between the pins and ulnar nerve measured. RESULTS: Median pin-to-nerve distances at the medial gutter and posteromedial compartment were 0 mm (interquartile range [IQR], 0-3 mm) and 2 mm (IQR, 0-6 mm), respectively. The ulnar nerve was pinned by 11/21 surgeons (52%) at the medial gutter, and 7/21 surgeons (33%) at the posteromedial compartment. Three of 21 surgeons (14%) pinned the ulnar nerve at both the medial gutter and the posteromedial compartment. Surgeon's experience and operation volume did not affect these outcomes (P > .05). CONCLUSIONS: Surgeons' ability to locate the ulnar nerve behind the posteromedial capsule using sole arthroscopic visualization, without external palpation, is poor. We recommend to proceed carefully when performing arthroscopic procedures in the posteromedial elbow, and identify and mobilize the ulnar nerve prior to any posteromedial capsular procedures.

Why does radial head arthroplasty fail today? A systematic review of recent literature.

Since the introduction of the radial head prosthesis (RHP) in 1941, many designs have been introduced. It is not clear whether prosthesis design parameters are related to early failure. The aim of this systematic review is to report on failure modes and to explore the association between implant design and early failure.A search was conducted to identify studies reporting on failed primary RHP. The results are clustered per type of RHP based on: material, fixation technique, modularity, and polarity. Chi-square tests are used to compare reasons for failure between the groups.Thirty-four articles are included involving 152 failed radial head arthroplasties (RHAs) in 152 patients. Eighteen different types of RHPs have been used.The most frequent reasons for revision surgery after RHA are (aseptic) loosening (30%), elbow stiffness (20%) and/or persisting pain (17%). Failure occurs after an average of 34 months (range, 0-348 months; median, 14 months).Press-fit prostheses fail at a higher ratio because of symptomatic loosening than intentionally loose-fit prostheses and prostheses that are fixed with an expandable stem (p < 0.01).Because of the many different types of RHP used to date and the limited numbers and evidence on early failure of RHA, the current data provide no evidence for a specific RHP design. Cite this article: EFORT Open Rev 2019;4:659-667. DOI: 10.1302/2058-5241.4.180099.

The Use of Eponyms for Surgical Approaches and Fractures in Elbow Surgery: Accuracy and Reliability Pre- and Post-Training.

The use of eponymous terms in orthopedic trauma surgery is common. In an assessment pre-training versus post-training at an AO Advanced Elbow Trauma Course, we aimed to report on (1) the accuracy and (2) reliability of 10 common eponymous terms used for surgical approaches and fractures in elbow surgery. Before training, eponyms were described correctly in 38% of questions versus 47% after training. The percentage of correct answers only improved significantly in one question (P<0.005). A generalized kappa of 0.37 before training versus 0.31 after training represents an overall fair reliability of the eponymous terms. In conclusion, the accuracy and reliability of eponymous terms used in elbow surgery is disappointing. Moreover, this type of standardized training format does not seem to improve the knowledge of eponymous terms of experienced trauma- and orthopedic surgeons. Therefore, we suggest considering descriptive terms or standardized fracture classifications instead of eponymous terms.

It's Not About The Biceps.

In the biomedical paradigm all symptoms and limitations are ascribed to discrete pathophysiology. However, a biopsychosocial health model that accounts for the important influence of mind-set and circumstances on illness may be preferable in the vast majority of cases. Some of the shortcomings of the biomedical model include an overreliance on tests and treatments. One major issue of the biomedical model is the raging epidemic of opioid misuse and opioid related overdose deaths as previously reported in North America. Emblematic of these issues is a 56-year-old male that had surgery for a rupture of the distal biceps in our clinic with psychosocial aspects of the illness that were underappreciated by the care team and had disastrous opioidcentric attempts at pain control leading to threats to hospital staff, and finally resulting in forcible removal by hospital security from the ward and national police from the hospital. One might argue that there is no higher priority than rejecting the biomedical model, understanding illness is its full complexity, and learning from the world's mistakes so that we don't repeat them.

Comparison of isometric triceps brachii force measurement in different elbow positions.

PURPOSE: Objective and reliable force measurement is necessary to monitor the rehabilitation after triceps brachii pathology, injuries, and posterior approach-based surgery. It is unclear at which amount of extension the triceps is best tested and if comparison to the uninjured sided is reliable. This study aims to identify the most reliable elbow position at which elbow extension force is measured using a dynamometer. Furthermore, it aims to compare the extension strength of the dominant arm with that of the nondominant arm. METHODS: Isometric elbow extension force of the dominant and nondominant arms of healthy subjects was measured. The measurements were taken in three sequences per arm in 0, 30, 60, 90, and 120 degrees of flexion. A subgroup repeated the measurements to analyze test-retest reliability using intraclass correlation. RESULTS: We included a total of 176 volunteers. The repeated measures analysis of variance for within-subject effect showed the lowest variation coefficient at 30 degrees of flexion. Extension forces showed a mean difference of 3.2-6.9 N in advantage of the dominant arm, resulting in ratios from 1.05 to 1.09. Learning curve analysis showed that during the first session in dominant and nondominant arms, less forces were exerted. CONCLUSION: The most reliable isometric triceps brachii muscle strength measurement was at 30 degrees of flexion of the elbow. Considering the learning curve, a first tryout session for both arms is indicated. Then, a second measurement suffices as no further learning curve is observed.

Normative values of isometric elbow strength in healthy adults: a systematic review.

BACKGROUND: Post-traumatic deformities such as biceps tendon rupture or (peri-)articular fractures of the elbow are often related to a decrease in muscle strength. Postoperative evaluation of these deformities requires normative values of elbow strength. The purpose of this systematic review was to determine these normative values of isometric elbow strength in healthy adults resulting from studies evaluating this strength (i.e. flexion, extension, pronation and supination strength). METHODS: The databases of PubMed, EMBASE and Web of Sciences were searched and screened for studies involving the isometric elbow strength as measured in asymptomatic volunteers. The quality of the studies was assessed and studies of low quality were excluded. RESULTS: Nineteen studies met the inclusion criteria and were of sufficiently high quality to be included in the present review. In these studies, elbow strength was measured in a total of 1880 healthy volunteers. The experimental set-up and devices used to measure elbow strength varied between studies. Using some assumptions, a normative values table was assembled. CONCLUSIONS: Large standard deviations of normative values in combination with different measurement devices used, as well as the different measurement positions of the subjects, demonstrated that there is no consensus about measuring the isometric elbow strength and therefore the normative values have to be interpreted with caution.

Effect of introducing an online system on the follow-up of elbow arthroplasty.

AIM: To evaluate the effect of introducing a structured online follow-up system on the response rate. METHODS: Since June 2015 we have set up an electronic follow-up system for prosthesis in orthopedic patients. This system allows prospective data gathering using both online and paper questionnaires. In the past all patients received questionnaires on paper. This study includes only patients who received elbow arthroplasty. Response rates before and after introduction of the online database were compared. After the implementation, completeness of the questionnaires was compared between paper and digital versions. For both comparisons Fisher's Exact tests were used. RESULTS: A total of 233 patients were included in the study. With the introduction of this online follow-up system, the overall response rate increased from 49.8% to 91.6% (P < 0.01). The response rate of 92.0% in the paper group was comparable to 90.7% in the online group (P > 0.05). Paper questionnaires had a completeness of 54.4%, which was lower compared to the online questionnaires where we reached full completeness (P < 0.01). Furthermore, non-responders proved to be younger with a mean age of 52 years compared to a mean age 62 years of responders (P < 0.05). CONCLUSION: The use of a structured online follow-up system increased the response rate. Moreover, online questionnaires are more complete than paper questionnaires.