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American Journal of Sports Medicine | 2017

Clinical Outcome After Arthroscopic Debridement and Microfracture for Osteochondritis Dissecans of the Capitellum

Rens Bexkens; Kim I.M. van den Ende; Paul T. Ogink; Christiaan J.A. van Bergen; Michel P. J. van den Bekerom; Denise Eygendaal

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) was assessed using the Oxford Elbow Score (OES) at final follow-up (OES range, 0-48). Range of motion and return to sports were recorded. Multivariable linear regression analysis was performed to determine predictors of postoperative OES. Results: Intraoperatively, there were 3 grade 1 lesions, 2 grade 2 lesions, 10 grade 3 lesions, 1 grade 4 lesion, and 59 grade 5 lesions. The mean postoperative OES was 40.8 (SD, ±8.0). An open capitellar physis was a predictor of better elbow outcome (5.8-point increase; P = .025), as well as loose body removal/grade 4-5 lesions (6.9-point increase; P = .0020) and shorter duration of preoperative symptoms (1.4-point increase per year; P = .029). Flexion slightly improved from 134° to 139° (P < .001); extension deficit slightly improved from 8° to 3° (P < .001). Pronation (P = .47) and supination did not improve (P = .065). Thirty-seven patients (55%) returned to their primary sport at the same level, and 5 patients (7%) returned to a lower level. Seventeen patients (25%) did not return to sport due to elbow-related symptoms, and 10 patients (13%) did not return due to non–elbow-related reasons. No complications were recorded. Conclusion: Arthroscopic debridement and microfracture for advanced capitellar osteochondritis dissecans provide good clinical results, especially in patients with open growth plate, loose body removal, and shorter duration of symptoms. However, only 62% of patients in this study returned to sports.


American Journal of Emergency Medicine | 2017

Effectiveness of reduction maneuvers in the treatment of nursemaid's elbow: A systematic review and meta-analysis

Rens Bexkens; Frederic J. Washburn; Denise Eygendaal; Michel P. J. van den Bekerom; Luke S. Oh

Background/Aim: Nursemaids elbow usually occurs in young children when longitudinal traction is placed on the arm. Several manipulative maneuvers have been described, although, the most effective treatment technique is yet unclear. The aim of this systematic review and meta‐analysis was to compare the two most commonly performed maneuvers (supination‐flexion and hyperpronation) in the treatment of nursemaids elbow. Methods: A literature search was performed in PubMed, Embase, and Cochrane databases to identify randomized controlled trials comparing supination‐flexion and hyperpronation. Data were extracted and pooled independently by two authors. Methodological quality assessment of included studies was performed. Meta‐analysis was performed using a fixed‐effect model in case of homogeneity across studies, and using a random‐effect model in case of heterogeneity. Heterogeneity was calculated with the χ2 test and inconsistency in study effects across trials was quantified by I2 values. Results: Seven randomized trials, including 701 patients (62% female), were included. A total of 350 patients were treated with the hyperpronation maneuver versus 351 patients who underwent the supination‐flexion maneuver. Meta‐analysis showed that hyperpronation was more effective than supination‐flexion (risk ratio, 0.34; 95% confidence interval, 0.23 to 0.49; I2, 35%). The absolute risk difference between maneuvers was 26% in favor of hyperpronation, resulting in a number needed to treat of 4 patients. Trials lacked blinding of assessors and universal pain measures. Conclusions: Hyperpronation was more effective in terms of success rate and seems to be less painful compared to the supination‐flexion maneuver in children with nursemaids elbow.


Journal of Shoulder and Elbow Surgery | 2017

Osteochondritis dissecans of the capitellum: lesion size and pattern analysis using quantitative 3-dimensional computed tomography and mapping technique

Rens Bexkens; Jacobien H. Oosterhoff; Tsung-Yuan Tsai; Job N. Doornberg; Michel P. J. van den Bekerom; Denise Eygendaal; Luke S. Oh

BACKGROUND The goals of this study were to evaluate the reliability of a quantitative 3-dimensional computed tomography (Q3DCT) technique for measurement of the capitellar osteochondritis dissecans (OCD) surface area, to analyze OCD distribution using a mapping technique, and to investigate associations between Q3DCT lesion quantification and demographic characteristics and/or clinical examination findings. METHODS We identified patients with capitellar OCD who presented to our orthopedic sports medicine practice between January 2001 and January 2016 and who had undergone a preoperative computed tomography scan (slice thickness ≤1.25 mm). A total of 17 patients with a median age of 15 years (range, 12-23 years) were included in this study. Three-dimensional polygon models were reconstructed after osseous structures were marked in 3 planes. Surface areas of the OCD lesion as well as the capitellum were measured. Observer agreement was assessed with the intraclass correlation coefficient (ICC). Heat maps were created to visualize OCD distribution. RESULTS Measurements of the OCD surface area showed almost perfect intraobserver agreement (ICC, 0.99; confidence interval [CI], 0.98-0.99) and interobserver agreement (ICC, 0.93; CI, 0.86-0.97). Measurements of the capitellar surface area also showed almost perfect intraobserver agreement (ICC, 0.97;CI, 0.91-0.99) and interobserver agreement (ICC, 0.86; CI, 0.46-0.96). The median OCD surface area was 101 mm2 (range, 49-217 mm2). On the basis of OCD heat mapping, the posterolateral zone of the capitellum was most frequently affected. OCDs in which the lateral wall was involved were associated with larger lesion size (P = .041), longer duration of symptoms (P = .030), and worse elbow extension (P = .013). CONCLUSIONS The ability to quantify the capitellar OCD surface area and lesion location in a reliable manner using Q3DCT and a mapping technique should be considered when detailed knowledge of lesion size and location is desired.


Shoulder & Elbow | 2018

Interobserver reliability of radiographic assessment after radial head arthroplasty

Rens Bexkens; Femke M.A.P. Claessen; Izaäk F. Kodde; Luke S. Oh; Denise Eygendaal; Michel P. J. van den Bekerom

Background Radiographs are part of routine clinical care after radial head arthroplasty (RHA). Therefore, the aim of this diagnostic study was to assess the interobserver reliability of radiographic assessment following RHA. Methods Anteroposterior (AP) and lateral radiographs of 24 consecutive patients who underwent press-fit bipolar RHA were evaluated with respect to 14 parameters by 14 orthopaedic surgeons specializing in the elbow: shaft loosening (AP, lateral), subcollar bone resorption, nonbridging heterotopic ossification, capitellar erosion, capitellar osteopenia, implant size, ulnohumeral joint gapping, ulnohumeral joint degeneration, proximal radio-ulnar joint congruency, stem size, stem positioning (AP, lateral) and component dissociation or polyethylene wear of the head with increased angulation. Observer agreement was evaluated using the multirater kappa (κ) measure. Results Nine of 14 parameters had poor interobserver agreement [κ = 0.0 to 0.20, confidence interval (CI) = 0.0 to 0.31). Four parameters had fair agreement: subcollar bone resorption (κ = 0.27, CI = 0.12 to 0.40), capitellar erosion (κ = 0.30, CI = 0.20 to 0.40), ulnohumeral joint degeneration (κ = 0.35, CI = 0.22 to 0.51) and stem positioning in AP view (κ = 0.24, CI = 0.14 to 0.36). One parameter had moderate agreement: nonbridging heterotopic ossification (κ = 0.47, CI = 0.31 to 0.64). Conclusions The overall interobserver reliability of radiographic assessment following press-fit bipolar RHA was poor among experienced elbow surgeons. Therefore, radiographic evaluation after RHA should be interpreted with caution when making treatment decisions.


Shoulder & Elbow | 2018

The kappa paradox

Rens Bexkens; Femke M.A.P. Claessen; Izaäk F. Kodde; Luke S. Oh; Denise Eygendaal; Michel P. J. van den Bekerom

With interest we have read the Letter to the Editor in response to our article. We agree with the authors of the letter that using Cohen’s kappa statistic to assess observer agreement of a qualitative variable has its limitations. However, the advantage of the kappa coefficient is its correction for the amount of agreement that can be expected to occur by chance alone. This feature of the kappa statistic has made it one of the most commonly used measures in agreement studies. Interestingly, a study may report a high absolute percentage of observer agreement (i.e. percentage of observers that agree on the matter, which is independent of the answer as long as they agree) and at the same time report a low kappa value, which is counter-intuitive. The reason for this statistical phenomenon, which is called the first kappa paradox, is the effect that prevalence of the subject under study in a data set has on marginal values. Because of this feature, an imbalance in case distribution will render lower kappa values. This paradox is not a limitation, rather a logical consequence of its purpose; to correctly interpret agreement adjusted for agreement by chance alone. We agree with the authors that one should critically review the study design when interpreting the results of interobserver studies. More specifically, one should look at the case distribution in case of low kappa values. With regard to our article, kappa values may have been higher when using more cases that demonstrated obvious abnormalities (i.e. different case distribution), as mentioned in the discussion of the paper. However, not many patients have radiographic abnormalities after radial head arthroplasty and therefore this study, and thus the kappa value, more closely resembles reality. In short, we agree that it is important not to neglect the kappa paradox but, taking the absolute number of radiographic abnormalities in daily practice into account, we stand by our original conclusion that one should be cautious when interpreting radiographs after radial head arthroplasty.


Clinical Orthopaedics and Related Research | 2018

Do Injured Adolescent Athletes and Their Parents Agree on the Athletes’ Level of Psychologic and Physical Functioning?

Jacobien H. Oosterhoff; Rens Bexkens; Ana-Maria Vranceanu; Luke S. Oh

Background Although a parent’s perception of his or her child’s physical and emotional functioning may influence the course of the child’s medical care, including access to care and decisions regarding treatment options, no studies have investigated whether the perceptions of a parent are concordant with that of an adolescent diagnosed with a sports-related orthopaedic injury. Identifying and understanding the potential discordance in coping and emotional distress within the athlete adolescent-parent dyads are important, because this discordance may have negative effects on adolescents’ well-being. Questions/purposes The purposes of this study were (1) to compare adolescent and parent proxy ratings of psychologic symptoms (depression and anxiety), coping skills (catastrophic thinking about pain and pain self-efficacy), and upper extremity physical function and mobility in a population of adolescent-parent dyads in which the adolescent had a sport-related injury; and (2) to compare scores of adolescents and parent proxies with normative scores when such are available. Methods We enrolled 54 dyads (eg, pairs) of adolescent patients (mean age 16 years; SD = 1.6) presenting to a sports medicine practice with sports-related injuries as well as their accompanying parent(s). We used Patient-reported Outcomes Measurement Information System questionnaires to measure adolescents’ depression, anxiety, upper extremity physical function, and mobility. We used the Pain Catastrophizing Scale short form to assess adolescents’ catastrophic thinking about pain and the Pain Self-efficacy Scale short form to measure adolescents’ pain self-efficacy. The accompanying parent, 69% mothers (37 of 54) and 31% fathers (17 of 54), completed parent proxy versions of each questionnaire. Results Parents reported that their children had worse scores (47 ± 9) on depression than what the children themselves reported (43 ± 9; mean difference 4.0; 95% confidence interval [CI], -7.0 to 0.91; p = 0.011; medium effect size -0.47). Also, parents reported that their children engaged in catastrophic thinking about pain to a lesser degree (8 ± 5) than what the children themselves reported (13 ± 4; mean difference 4.5; 95% CI, 2.7-6.4; p < 0.001; large effect size 1.2). Because scores on depression and catastrophic thinking were comparable to the general population, and minimal clinically important difference scores are not available for these measures, it is unclear whether the relatively small observed differences between parents’ and adolescents’ ratings are clinically meaningful. Parents and children were concordant on their reports of the child’s upper extremity physical function (patient perception 47 ± 10, parent proxy 47 ± 8, mean difference -0.43, p = 0.70), mobility (patient perception 43 ± 9, parent proxy 44 ± 9, mean difference -0.59, p = 0.64), anxiety (patient perception 43 ± 10, parent proxy 46 ± 8, mean difference -2.1, p = 0.21), and pain self-efficacy (patient perception 16 ± 5, parent proxy 15 ± 5, mean difference 0.70, p = 0.35). Conclusions Parents rated their children as more depressed and engaging in less catastrophic thinking about pain than the adolescents rated themselves. Although these differences are statistically significant, they are of a small magnitude making it unclear as to how clinically important they are in practice. We recommend that providers keep in mind that parents may overestimate depressive symptoms and underestimate the catastrophic thinking about pain in their children, probe for these potential differences, and consider how they might impact medical care. Level of Evidence Level I, prognostic study.


American Journal of Sports Medicine | 2018

Decreased Defect Size and Partial Restoration of Subchondral Bone on Computed Tomography After Arthroscopic Debridement and Microfracture for Osteochondritis Dissecans of the Capitellum

Rens Bexkens; Christiaan J.A. van Bergen; Michel P. J. van den Bekerom; Gino M. M. J. Kerkhoffs; Denise Eygendaal

Background: Arthroscopic debridement and microfracture are considered the primary surgical treatment for capitellar osteochondritis dissecans (OCD). Healing of the subchondral bone plays an essential role in cartilage repair, while lack of healing is related to the development of osteoarthritis. To date, it is unknown to what extent healing of the subchondral bone occurs after this technique in the elbow. Purpose: To analyze defect size changes and subchondral bone healing with computed tomography (CT) after arthroscopic debridement and microfracture for advanced capitellar OCD. Study Design: Case series; Level of evidence, 4. Methods: Between 2009 and 2016, 67 patients underwent arthroscopic debridement and microfracture for advanced capitellar OCD. Fifty-four patients (81% follow-up rate) with CT scans were included (mean ± SD: preoperative, 4.0 ± 1.7 months; postoperative, 29 ± 9.0 months). OCD defect size was assessed by measuring the largest diameter in 3 directions: medial-lateral direction (coronal plane) and anterior-posterior direction and depth (both in sagittal plane). Healing of the OCD was divided into 3 categories: good—complete osseous union or ossification; fair—incomplete osseous union or ossification but improved; poor—no changes between pre- and postoperative scans. Postoperative clinical outcome was assessed with the Oxford Elbow Score (OES) at the same time as the postoperative CT scan. Results: There were 30 female and 24 male patients (age, 15.7 ± 3.2 years). Defect size decreased (P < .001) in all 3 directions (medial-lateral × anterior-posterior × depth) at 29 ± 9.0 months: preoperatively, 7.9 ± 2.8 × 8.0 ± 3.2 × 4.1 ± 1.5 mm; postoperatively, 3.5 ± 3.3 × 4.0 ± 3.5 × 1.6 ± 1.4 mm. Healing of the subchondral bone was graded as good in 19 defects (35%), fair in 27 (50%), and poor in 8 (15%). The mean postoperative OES score was 40 ± 8.4. Neither postoperative defect size nor healing grade correlated with the OES (P > .05). Conclusion: Arthroscopic debridement and microfracture for advanced capitellar OCD result in improved (ie, decreased) defect size at a mean follow-up of 29 months, both in width and in depth. Healing of the subchondral bone was either good or fair in 85%. Interestingly, CT findings did not correlate with clinical outcomes.


Knee Surgery, Sports Traumatology, Arthroscopy | 2017

Donor-site morbidity after osteochondral autologous transplantation for osteochondritis dissecans of the capitellum: a systematic review and meta-analysis

Rens Bexkens; Paul T. Ogink; Job N. Doornberg; Gino M. M. J. Kerkhoffs; Denise Eygendaal; Luke S. Oh; Michel P. J. van den Bekerom


Arthroscopy | 2018

Topographic Analysis of 2 Alternative Donor Sites of the Ipsilateral Elbow in the Treatment of Capitellar Osteochondritis Dissecans

Rens Bexkens; Michel P. J. van den Bekerom; Denise Eygendaal; Luke S. Oh; Job N. Doornberg


Clinical Orthopaedics and Related Research | 2018

What Is the Relationship of Fear Avoidance to Physical Function and Pain Intensity in Injured Athletes

Stefan F. Fischerauer; Mojtaba Talaei-Khoei; Rens Bexkens; David Ring; Luke S. Oh; Ana-Maria Vranceanu

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Gino M. M. J. Kerkhoffs

Vanderbilt University Medical Center

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