Professor Dr. Denise Eygendaal

A previous anatomic study has revealed that the lateral collateral ligament (LCL) complex of the elbow has a Y-shaped configuration, which consists of a superior, an anterior, and a posterior band. The LCL complex, including the annular ligament, functions as a 3-dimensional (3D) Y-shaped structure. On the basis of this concept, joint laxity after transection of the anterior band was studied in 5 normal, fresh-frozen cadaver elbows with a 3D kinematic testing apparatus. Cutting the anterior band produced significant laxity to varus torque with a mean 5.9 degree at 10 degree of elbow flexion and caused significant laxity to torque in external rotation with a mean 8.5 degree at 40 degree of flexion. No significant laxity was observed during application of valgus or internal rotational torque. Further transection of the posterior band resulted in gross instability with dislocation of the ulnohumeral joint. The laxity occurring after severance of the anterior band suggests that these fibers play a role in preservation of elbow stability against varus and external rotational torque. These results indicate that the LCL functions as a complex with a Y structure and not as an isolated linear ligament. A concept of conjoint point is hypothesized for the function of the LCL complex to restrain posterolateral rotatory instability.

The elbow is prone to stiffness due to its unique anatomy and profound capsular reaction to inflammation. The resulting movement impairment may significantly interfere with a patient’s activities of daily living. Trauma (including surgery for trauma), posttraumatic arthritis, and heterotopic ossification (HO) are the most common causes of elbow stiffness. In stiffness caused by soft tissue contractures, initial conservative treatment with physiotherapy (PT) and splinting is advised. In cases in which osseous deformities limit range of motion (e.g. malunion, osseous impingement, or HO), early surgical intervention is recommended. Open and arthroscopic arthrolysis are the primary surgical options. Arthroscopic arthrolysis has a lower complication and revision rate but has narrower indications. Early active mobilization using PT after surgery is recommended in postoperative rehabilitation and may be complemented by splinting or continuous passive motion therapy. Most results are gained...

Background:Despite the expanding body of literature on radial head arthroplasty, the increasing understanding of elbow anatomy, biomechanics, and kinetics, and the evolution of surgical techniques and prosthesis designs, there is currently no evidence to support one type of radial head prosthesis over another. The purposes of the present report were to review the literature and to explore the association between prosthesis design variables and the timing of surgery and the outcome of modern radial head arthroplasty. Methods:The literature search was limited to studies involving skeletally mature patients. Major databases were searched from January 1940 to May 2015 to identify studies relating to functional and subjective outcomes and radiographic results after radial head arthroplasty. Results:Thirty articles involving 727 patients were included. Seventy percent of the implants were made of cobalt-chromium, 15% were made of pyrocarbon, 9% were made of titanium, and 6% were made of Vitallium. Seventy percent were monopolar, and 30% were bipolar. Twenty-one percent were cemented in place, 32% were press-fit, 32% were intentionally loose-fit, and 15% were fixed with an expandable stem. The weighted average duration of follow-up was 45 months. The rate of revision ranged from 0% to 29% among studies. The incidence of revision was 8% during 2,714 person-years of follow-up across all 727 patients, yielding a crude overall revision rate of 2.06 per 100 person-years of follow-up. The revision rate was not significantly affected by prosthesis polarity, material, or fixation technique, nor was it significantly affected by the delay of treatment. There was also no significant effect of prosthesis polarity, material, or fixation technique on postoperative range of motion. The Mayo Elbow Performance Score was only reported for half of the overall patient population, but, among those patients, the combined rate of excellent and good results was 85%. Seven percent of the overall patient population underwent secondary surgery about the elbow other than revision surgery. Twenty-three percent were reported to have 1 or more complications. Conclusions:On the basis of our analysis of the peer-reviewed English-language literature on radial head arthroplasty from January 1940 to May 2015, there seems to be no evidence to support one type of radial head prosthesis over another. The only exception is that silicone prostheses have been shown to be biologically and biomechanically insufficient. Level of Evidence:Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Sports such as baseball, football, swimming, volleyball, javelin, waterpolo, and tennis are examples of overhead sports that subject the shoulder to extreme ranges of motion, forces, and accelerations/decelerations over many repetitions. This overhead motion also generates extraordinary demands on the elbow joint. The posterior compartment undergoes tensile, compressive, and torsional forces during acceleration and deceleration phases. This may result in valgus extension overload within the posterior compartment, potentially leading to chondromalacia, osteophyte formation, loose bodies formation, proximal ulna stress fractures, triceps pathology, or physeal injuries.

Pediatric supracondylar humerus fractures (pSCHFs) may be challenging injuries to treat because of the potential residual deformity. There is debate regarding the technical aspects of adequate closed reduction and crossed Kirschner wire (K-wire) fixation. Do surgeons have an agreement on the aspects of the fixation of pSCHFs? Radiographs of 20 patients from a cohort of 154 patients with pSCHFs treated with closed reduction and crossed K-wire fixation were selected. Forty-four surgeons viewed the postoperative radiographs and diagnosed the presence or absence of technical flaws and made a recommendation for or against reoperation. An expert panel of three orthopedic and trauma surgeons provided a reference standard for technical factors. Furthermore, final outcome 2 years after trauma was assessed. There was limited agreement on potential technical flaws (ICC 0.15–0.28), radiographic measures of alignment (ICC for anterior humeral line and Baumann angle of 0.37 and 0.23 respectively), the quality of postoperative reduction, position of the elbow in cast, and recommendation for repeat surgery (ICCs between 0.23 and 0.40). Sensitivity and specificity for these questions ranged from 0.59 to 0.90. There was no correlation between the voted quality of postoperative reduction and loss of reduction or final function. Surgeons have limited agreement on the quality of postoperative results in pSCHFs and the indication for reoperation. Reviewing postoperative radiographs may present a good learning opportunity and could help improve skills, but it is not a validated method for quality control and has to be seen in light of clinical outcome.

Background New surgical approaches have been developed to optimise elbow function after total elbow arthroplasty (TEA). Currently, there is no consensus on the best surgical approach. This study aims to investigate the functional outcomes, prosthetic component position and complication rates after a triceps-sparing and a triceps-detaching approach in TEA. Methods and analysis A multicentre prospective comparative cohort study will be conducted. All patients with an indication for primary TEA will enrol in either the triceps-sparing or the triceps-detaching cohort. Primary outcome measure is elbow function, specified as fixed flexion deformity. Secondary outcome parameters are self-reported and objectively measured physical functioning, including triceps force, prosthetic component position in standard radiographs and complications. Discussion The successful completion of this study will clarify which surgical approach yields better functional outcomes, better prosthetic component po...

BACKGROUND Lateral epicondylitis (LE) is a highly prevalent musculoskeletal disorder in workers, often associated with physically demanding work. Knowledge of work-relatedness of LE is crucial to develop appropriate preventive measures. This study investigates the prospective association between work-related physical risk factors and LE. METHODS A systematic literature review was conducted in MedLine using PubMed from January 1, 2010 until February 16, 2021. Published reports were included if: (1) LE was clinically assessed, (2) exposure to work-related physical risk factors was assessed, and (3) associations between LE and work-related physical risk factors were reported in prospective studies. Quality of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation. RESULTS In total, 318 workers with LE from a population of 5036 workers in five studies were included. Meta-analyses revealed high-quality evidence for associations between LE and a Strain Index (SI) score >5.1 (odds ratio [OR]: 1.75, 95% confidence interval (CI): 1.11-2.78) and moderate-quality evidence for forearm rotation >4 h/day or forearm rotation ≥45° for ≥45% time (OR: 1.85, 95% CI: 1.10-3.10). Gripping, flexion and extension of the wrist, and repetitive movements showed no significant associations with LE. CONCLUSION High-quality evidence was found indicating that a higher SI increased the risk of LE. Moderate-quality evidence was found for an association between forearm rotation and LE. No associations were found between other physical risk factors and LE. Primary preventive interventions should focus on a reduction of the SI and of high forearm rotation in work.

Children often present at the emergency department with a suspected elbow fracture. Sometimes, the only radiological finding is a ‘fat pad sign’ (FPS) as a result of hydrops or haemarthros. This sign could either be the result of a fracture, or be due to an intra-articular haematoma without a concomitant fracture. There are no uniform treatment guidelines for this common population. The aims of this study were (1) to obtain insight into FPS definition, diagnosis, and treatment amongst international colleagues, and (2) to identify a uniform definition based on radiographic measurements with optimal cut-off points via a receiver operating characteristic (ROC) curve. An online international survey was set up to assess the diagnostic and treatment strategies, criteria, and definitions of the FPS, the probability of an occult fracture, and the presence of an anterior and/or posterior FPS on 20 radiographs. Additionally, the research team performed radiographic measurements to identify cu...

Clavicle fractures are commonly seen in the pediatric and adolescent populations. In contrast, congenital pseudarthrosis of the clavicle is rare. Although both conditions may present with similar signs and symptoms, especially in the very young, clear differences exist. Clavicle fractures are often caused by trauma and are tender on palpation, while pseudarthrosis often presents with a painless protuberance on the clavicle, which becomes more prominent as the child grows. Its presence may only become apparent after trauma, as it is usually asymptomatic. The diagnosis is confirmed on plain radiography, which shows typical features to distinguish both entities. Both clavicle fractures and congenital pseudarthrosis are generally treated conservatively with a high success rate. Operative treatment for a fracture can be indicated in the case of an open fracture, severely displaced fracture, floating shoulder, neurovascular complications or polytrauma. Congenital pseudarthrosis requires o...

Biceps brachii is composed of two separate heads and is innervated by a branch of the musculocutaneous nerve [1]. The proximal tendon of the long head is attached to the supraglenoid tubercle, and the proximal tendon of the short head is attached to the coracoid process. The biceps (muscle and tendon) rotates 90° externally from origin to insertion onto the bicipital tuberosity [2] and acts on three joints: the glenohumeral, ulnohumeral, and proximal radioulnar joints. A completely bifurcated distal tendon insertion is not uncommon [3, 4]. The short head of the distal biceps tendon was reported to insert more distally, and the long head was inserted more eccentric and medial. The moment arm of the long head was higher in supination, and the short head had a higher moment arm in neutral position and pronation [5]. These findings may allow functional independence and isolated rupture of each portion and may have consequences for restoring the native anatomy during a surgical repair. S...

BACKGROUND Reliably recognizing the overall pattern and specific characteristics of proximal humerus fractures may aid in surgical decision-making. With conventional onscreen imaging modalities, there is considerable and undesired interobserver variability, even when observers receive training in the application of the classification systems used. It is unclear whether three-dimensional (3D) models, which now can be fabricated with desktop printers at relatively little cost, can decrease interobserver variability in fracture classification. QUESTIONS/PURPOSES Do 3D-printed handheld models of proximal humerus fractures improve agreement among residents and attending surgeons regarding (1) specific fracture characteristics and (2) patterns according to the Neer and Hertel classification systems? METHODS Plain radiographs, as well as two-dimensional (2D) and 3D CT images, were collected from 20 patients (aged 18 years or older) who sustained a three-part or four-part proximal humerus fracture treated at a Level I trauma center between 2015 and 2019. The included images were chosen to comprise images from patients whose fractures were considered as difficult-to-classify, displaced fractures. Consequently, the images were assessed for eight fracture characteristics and categorized according to the Neer and Hertel classifications by four orthopaedic residents and four attending orthopaedic surgeons during two separate sessions. In the first session, the assessment was performed with conventional onscreen imaging (radiographs and 2D and 3D CT images). In the second session, 3D-printed handheld models were used for assessment, while onscreen imaging was also available. Although proximal humerus classifications such as the Neer classification have, in the past, been shown to have low interobserver reliability, we theorized that by receiving direct tactile and visual feedback from 3D-printed handheld fracture models, clinicians would be able to recognize the complex 3D aspects of classification systems reliably. Interobserver agreement was determined with the multirater Fleiss kappa and scored according to the categorical rating by Landis and Koch. To determine whether there was a difference between the two sessions, we calculated the delta (difference in the) kappa value with 95% confidence intervals and a two-tailed p value. Post hoc power analysis revealed that with the current sample size, a delta kappa value of 0.40 could be detected with 80% power at alpha = 0.05. RESULTS Using 3D-printed models in addition to conventional imaging did not improve interobserver agreement of the following fracture characteristics: more than 2 mm medial hinge displacement, more than 8 mm metaphyseal extension, surgical neck fracture, anatomic neck fracture, displacement of the humeral head, more than 10 mm lesser tuberosity displacement, and more than 10 mm greater tuberosity displacement. Agreement regarding the presence of a humeral head-splitting fracture was improved but only to a level that was insufficient for clinical or scientific use (fair to substantial, delta kappa = 0.33 [95% CI 0.02 to 0.64]). Assessing 3D-printed handheld models adjunct to onscreen conventional imaging did not improve the interobserver agreement for pattern recognition according to Neer (delta kappa = 0.02 [95% CI -0.11 to 0.07]) and Hertel (delta kappa = 0.01 [95% CI -0.11 to 0.08]). There were no differences between residents and attending surgeons in terms of whether 3D models helped them classify the fractures, but there were few differences to identify fracture characteristics. However, none of the identified differences improved to almost perfect agreement (kappa value above 0.80), so even those few differences are unlikely to be clinically useful. CONCLUSION Using 3D-printed handheld fracture models in addition to conventional onscreen imaging of three-part and four-part proximal humerus fractures does not improve agreement among residents and attending surgeons on specific fracture characteristics and patterns. Therefore, we do not recommend that clinicians expend the time and costs needed to create these models if the goal is to classify or describe patients' fracture characteristics or pattern, since doing so is unlikely to improve clinicians' abilities to select treatment or estimate prognosis. LEVEL OF EVIDENCE Level III, diagnostic study.

The aim of arthroscopic debridement is creating a stable rim and improving nutrient supply by chondral abrasion to provide an optimal environment for the cartilage to regenerate. Microfracturing can be added to further improve nutrient supply and formation of fibrocartilaginous tissue [1, 2]. Additionally, loose or fixed bodies can be removed, or impinging posteromedial olecranon osteophytes debrided, in advanced OCD lesions or concomitant posteromedial impingement, respectively [3, 4]. Concomitant posteromedial impingement is rare among the young overhead athlete diagnosed with OCD of the elbow and more likely in the older overhead athlete.

BACKGROUND The incidence of triceps insufficiency after total elbow arthroplasty (TEA) varies in the literature, and a consensus on treatment strategy is lacking. We review the incidence, the risk factors, the clinical presentation, and the diagnosis and treatment of triceps insufficiency after TEA. Based on this information, we have formulated recommendations for clinical practice. METHODS We performed a systematic review of the literature from January 2003 to April 2020 to identify studies that investigated triceps function following TEA by searching the PubMed, Cochrane, and Embase databases. Eligible studies (1) reported on triceps function following primary or revision TEA for every indication, regardless of technique (e.g., bone grafts), (2) included ≥6 adult patients, (3) had the full-text article available, and (4) had a minimum follow-up of 1 year. RESULTS Eighty studies with a total of 4,825 TEAs were included. The quality was low in 15 studies, moderate in 64 studies, and...

We present a novel fabrication and surgical approach for anatomical reconstruction of a fractured radial head using a patient-specific radial head prosthesis (RHP) made of polymethylmethacrylate (PMMA) bone cement. To this end, the use of PMMA bone cement for prosthesis fabrication was initially investigated using computational modeling and experimental methods. The RHP was fabricated through casting of PMMA bone cement in a silicone mold in the operating room before implantation. To enhance the precision of bony preparation for replacement of the radial head, a patient-specific surgical guide for accurate resection of the radial neck with the desired length was developed. Post-surgical clinical examinations revealed biomechanical restoration of elbow function, owing to the use of the patient-specific RHP and surgical guide. Importantly, follow-up radiographs after a mean follow-up of 18 months revealed bone preservation at the bone–prosthesis interface without any signs of erosion ...

Background Wave surfing will debut in the next Olympic Games and is increasingly popular as a sport. Chronic shoulder complaints are frequently reported amongst surfers, though literature researching its pathophysiology and prevention is scarce. This article provides an overview of the current literature, proposes a potential pathogenesis and a potential physiotherapeutic prevention program for surf-induced shoulder complaints. Methods A systematic review was performed considering the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for articles regarding kinematic analysis of the surf paddling movement. Data sources were Embase, MEDLINE (PubMed) and Research gate. We included case series and cohort studies that originally studied or described the paddle movement made by wave surfers, studies that reported on kinesiologic analysis with nerve conduction studies and studies on 3D motion analysis of the shoulder while paddling. Results Eight origin...

Purpose To evaluate the effect of three-dimensional virtual pre-operative planning (3DVP) on the incidence of dorsal screw penetration after volar plating of distal radius fractures. Methods A cross-sectional diagnostic imaging study was performed. Twenty out of 50 patients were randomly selected from our index prospective cohort (IPC): a prior study evaluating dorsal tangential views (DTVs) in reducing dorsal screw penetration in internal fixation of intra-articular distal radius fractures using post-operative CT scans to quantify screw protrusion. Pre-operative CTs from this cohort were now used for 3DVP by three experienced orthopaedic trauma surgeons (supplementary video). 3DVP was compared with the corresponding post-operative CT for assessing screw lengths and incidence of dorsal penetration. The Wilcoxon Signed Ranks test was used to compare screw lengths and the Fishers’ exact for incidence of penetration. Results Three surgeons performed 3DVP for 20 distal radius fractures ...

PURPOSE We performed a biomechanical analysis using the finite element method to assess the effects of plate length and the number of screws on construct stiffness, stress distribution, and fracture displacement in the fixation of type A2 distal humerus fractures. METHODS A 3-dimensional humerus model was constructed using computed tomography of a healthy man. After creating a 2-mm extra-articular fracture gap, orthogonal double-plate fixation was performed with an incremental increase in plate length and the number of screws, creating 17 fixation models. Four screws were placed in each plate's distal segment, and the number of screws was increased incrementally in the segment proximal to the fracture, starting from 2 in the medial (M) and 2 in the lateral (L) plate (M2∗L2). RESULTS The fifth screw proximal to the fracture in the lateral plate (L5) played an essential role in increasing stiffness under bending, axial, and torsional forces surpassing the intact bone, which may have been due to the bypassing of the stress riser area. Minimum construct stiffness was created when 5 (M3∗L2) screws were inserted into the proximal segment. For bending forces, the M4∗L2 construct was stronger than M3∗L3 (total 6 proximal screws), and M5∗L3 was stronger than M4∗L4 (total 8 proximal screws), showing higher stiffness when the plates ended at different levels. The M4∗L2 construct (6 screws) had stiffness comparable with M4∗L3, M4∗L4, and M5∗L4 during bending, showing comparable stiffness with the least instrumentation density. CONCLUSION Our findings suggested M3∗L5 as the optimum and M3∗L2 as the minimum construct to resist all bending, axial and torsional forces. CLINICAL RELEVANCE Applying the results may improve surgical techniques, decrease the rate of complications, including fixation failure and nerve injury, and optimize the time of surgery. Moreover, hardware removal is less cumbersome with fewer screws.

Background This study aims to use the Dutch Arthroplasty Register data to report an overview of the contemporary indications and implant designs, and report the short-term survival of radial head arthroplasty. Methods From the Dutch Arthroplasty Register, data on patient demographics, surgery and revision were extracted for radial head arthroplasties performed from January 2014 to December 2019. Implant survival was calculated using the Kaplan–Meier method. Results Two hundred fifty-eight arthroplasties were included with a median follow-up of 2.2 years. The most common indication was a fracture of the radial head (178, 69%). One hundred thirty-nine (68%) of the prostheses were of bipolar design, and the most commonly used implant type was the Radial Head System (Tornier; 134, 51%). Of the 258 included radial head arthroplasties, 16 were revised at a median of six months after surgery. Reason for revision was predominantly aseptic loosening (9). The overall implant survival was 95.8...

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 ...

Background: Various surgical treatment techniques have been developed to treat capitellar osteochondritis dissecans; however, the optimal technique remains the subject of ongoing debate. Purpose: To evaluate clinical outcomes after arthroscopic debridement and microfracture for advanced capitellar osteochondritis dissecans. Study Design: Case series; Level of evidence, 4. Methods: Between 2008 and 2015, the authors followed 77 consecutive patients (81 elbows) who underwent arthroscopic debridement and microfracture, and loose body removal if needed, for advanced capitellar osteochondritis dissecans. Seventy-one patients (75 elbows) with a minimum follow-up of 1 year were included. The mean age was 16 years (SD, ±3.3 years; range, 11-26 years) and the mean follow-up length was 3.5 years (SD, ±1.9 years; range, 1-8.2 years). Based on CT and/or MRI results, 71 lesions were classified as unstable and 4 as stable. Clinical elbow outcome (pain, function, and social-psychological effect) w...