Purpose:Simple bone cysts are among the most prevalent benign cystic tumor-like lesions in children. Proximal femoral simple bone cysts may require specific treatment because of increased fracture... Show morePurpose:Simple bone cysts are among the most prevalent benign cystic tumor-like lesions in children. Proximal femoral simple bone cysts may require specific treatment because of increased fracture risk. With limited literature available on this specific localization, consensus regarding optimal treatment is lacking. We present a large international multicenter retrospective cohort study on proximal femoral simple bone cysts.Methods:All consecutive pediatric patients with proximal femoral simple bone cyst from 10 tertiary referral centers for musculoskeletal oncology were included (2000–2021). Demographics, primary treatment, complications, and re-operations were evaluated. Primary outcomes were time until full weight-bearing and failure-free survival.Results:Overall, 74 simple bone cyst patients were included (median age 9 years (range = 2–16), 56 (76%) male). Median follow-up was 2.9 years (range = 0.5–21). Index procedure was watchful waiting (n = 6), percutaneous procedure (n = 12), open procedure (n = 50), or osteosynthesis alone (n = 6). Median time until full weight-bearing was 8 weeks (95% confidence interval = 0.1–15.9) for watchful waiting, 9.5 (95% confidence interval = 3.7–15.3) for percutaneous procedure, 11 (95% confidence interval = −0.7 to 13.7) for open procedure, and 6.5 (95% confidence interval = 5.9–16.1) for osteosynthesis alone (p = 0.58). Failure rates were 33%, 58%, 29%, and 0%, respectively (p = 0.069). Overall failure-free survival at 1, 2, and 5 years was 77.8% (95% confidence interval = 68.2–87.4), 69.5% (95% confidence interval = 58.5–80.5), and 62.0% (95% confidence interval = 47.9–76.1), respectively.Conclusion:A preferred treatment for proximal femoral simple bone cysts remains unclear, with comparable failure rates and times until full weight-bearing. Watchful waiting may be successful in certain cases. If not feasible, osteosynthesis alone can be considered. Treatment goals should be cyst control, minimizing complications and swift return to normal activities. Therefore, an individualized balance should be made between undertreatment, with potentially higher complication risks versus overtreatment, resulting in possible larger interventions and accompanying complications.Level of evidence:Level IV, retrospective multicentre study Show less
Kouswijk, H.W. van; Tolk, J.J.; Bommel, C.P.E. van; Reijman, M.; Kempink, D.R.J.; Witte, P.B. de 2023
Background: Proximal femoral and/or pelvic osteotomies (PFPOs) can be indicated for a multitude of hip pathologies in (often asymptomatic) children, to prevent future hip problems. These procedures... Show moreBackground: Proximal femoral and/or pelvic osteotomies (PFPOs) can be indicated for a multitude of hip pathologies in (often asymptomatic) children, to prevent future hip problems. These procedures can result in significant blood loss. Tranexamic acid (TXA) is an antifibrinolytic agent routinely administered in adult trauma and joint reconstruction surgery to reduce blood loss. TXA is also registered for use in children and reported safe and beneficial for pediatric trauma, cardiac, and spinal surgery. However, for pediatric orthopedics, particularly for PFPOs, the available evidence is limited. Therefore, the current trial will investigate the potential reducing effect of preoperative TXA on intraoperative blood loss in pediatric PFPOs.Methods: In this single-center, double-blind, randomized placebo-controlled trial, we aim to include 180 participants aged from 1 to 18 years undergoing PFPOs for any indication at our institution. Participants will be randomized to receive either TXA or placebo (saline) during anesthetic induction. The primary outcome is intraoperative estimated blood loss (mL/kg), which is determined gravimetrically. Secondary outcomes include the percentage of patients with excessive blood loss (>20 mL/kg), procedure time and hospital stay, and postoperative hemoglobin level changes.Discussion: This will be the first prospective study investigating the effect of preoperative TXA on intraoperative blood loss in pediatric PFPOs. Its results will help to determine whether it would be advisable to adopt preoperative TXA as a standard medication to minimize blood loss and prevent complications in this vulnerable population.Trial registration: EudraCT: 2022-002384-30. Prospectively registered on September 26, 2022. Show less
Meier, M.E.; Appelman-Dijkstra, N.M.; Collins, M.T.; Geels, R.E.S.; Stanton, R.P.; Witte, P.B. de; ... ; Sande, M.A.J. van de 2023
This study aimed to evaluate the prevalence of and risk factors for coxa vara deformity in patients with fibrous dysplasia/McCune-Albright syndrome (FD/MAS). This study was conducted at the... Show moreThis study aimed to evaluate the prevalence of and risk factors for coxa vara deformity in patients with fibrous dysplasia/McCune-Albright syndrome (FD/MAS). This study was conducted at the National Institutes of Health and Leiden University Medical Center. All patients with any subtype of FD/MAS, FD involving the proximal femur, one or more X-rays available and age <30 years were included. X-rays were scored for the neck-shaft angle (NSA). Varus deformity was defined as NSA <110 degrees or >10 degrees below age-specific values. Risk factors for deformity were assessed by nested case-control analysis, comparing patients and femurs with and without deformity, and by linear mixed effects model, modeling temporal NSA decrease (the natural course of the NSA) in non-operated femurs with two or more X-rays. Assessed variables included growth hormone excess, hyperthyroidism, hypophosphatemia, >25% of the femur affected, calcar destruction, radiolucency, and bilateral involvement. In total 180 patients were studied, 57% female. Mean +/- SD baseline age was 13.6 +/- 7.5 years; median follow-up 5.4 (interquartile range [IQR], 11.1) years. Sixty-three percent (63%) were diagnosed with MAS. A total of 94 patients were affected bilaterally; 274 FD femurs were analyzed; 99 femurs had a varus deformity (36%). In the nested case-control analysis, risk factors were as follows: presence of MAS (p < 0.001), hyperthyroidism (p < 0.001), hypophosphatemia (p < 0.001), high percentage of femur affected (p < 0.001), and calcar destruction (p < 0.001). The linear mixed effects model included 114 femurs, identified risk factors were: growth hormone excess (beta = 7.2, p = 0.013), hyperthyroidism (beta = 11.3, p < 0.001), >25% of the femur affected (beta = 13.2, p = 0.046), calcar destruction (beta = 8.3, p = 0.004), radiolucency (beta = 3.9, p = 0.009), and bilateral involvement (beta = 9.8, p = 0.010). Visual inspection of the graph of the model demonstrated most progression of deformity if NSA <120 degrees with age < 15 years. In conclusion, in tertiary care centers, the prevalence of FD/MAS coxa vara deformity was 36%. Risk factors included presence of MAS, high percentage of femur affected, calcar destruction, radiolucency, NSA <120 degrees and age < 15 years. (c) 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). Show less
Mulder, F.E.C.M.; Witlox, M.A.; Dirksen, C.D.; Witte, P.B. de; Vos-Jakobs, S. de; Ham, A.M.T.; ... ; Mathijssen, N.M.C. 2023
Background: Developmental Dysplasia of the Hip (DDH) is one of the most common pediatric orthopedic disorders, affecting 1-3% of all newborns. The optimal treatment of centered DDH is currently... Show moreBackground: Developmental Dysplasia of the Hip (DDH) is one of the most common pediatric orthopedic disorders, affecting 1-3% of all newborns. The optimal treatment of centered DDH is currently under debate. This randomized controlled trial aims to study the (cost-)effectiveness of active monitoring versus abduction treatment for infants with centered DDH. Methods: This is a multicenter, parallel-group, open-label, non-inferiority randomized controlled trial studying the (cost-)effectiveness of active monitoring versus abduction treatment for infants with centered DDH in fourteen hospitals in the Netherlands. In total, 800 infants with centered DDH (Graf IIa-/IIb/IIc), aged 10-16 weeks, will be randomly allocated to the active monitoring or abduction treatment group. Infants will be followed up until the age of 24 months. The primary outcome is the rate of normal hips, defined as an acetabular index lower than 25 degrees on an antero-posterior radiograph, at the age of 12 months. Secondary outcomes are the rate of normal hips at the age of 24 months, complications, time to hip normalization, the relation between baseline patient characteristics and the rate of normal hips, compliance, costs, cost-effectiveness, budget impact, health-related quality of life (HRQoL) of the infant, HRQoL of the parents/caregivers, and parent/caregiver satisfaction with the treatment protocol.Discussion: The outcomes of this randomized controlled trial will contribute to improving current care-as-usual for infants with centered DDH. Show less
Geloven, T.P.G. van; Heijden, L. van der; Laitinen, M.K.; Campanacci, D.A.; Doring, K.; Dammerer, D.; ... ; EPOS Study Grp 2023
Background: Aneurysmal bone cysts (ABC) are rare benign cystic bone tumors, generally diagnosed in children and adolescents. Proximal femoral ABCs may require specific treatment strategies because... Show moreBackground: Aneurysmal bone cysts (ABC) are rare benign cystic bone tumors, generally diagnosed in children and adolescents. Proximal femoral ABCs may require specific treatment strategies because of an increased pathologic fracture risk. As few reports are published on ABCs, specifically for this localization, consensus regarding optimal treatment is lacking. We present a large retrospective study on the treatment of pediatric proximal femoral ABCs. Methods: All eligible pediatric patients with proximal femoral ABC were included, from 11 tertiary referral centers for musculo-skeletal oncology (2000-2021). Patient demographics, diagnostics, treatments, and complications were evaluated. Index procedures were categorized as percutaneous/open procedures and osteosynthesis alone. Primary outcomes were: time until full weight-bearing and failure-free survival. Failure was defined as open procedure after primary surgery, >3 percutaneous procedures, recurrence, and/or fracture. Risk factors for failure were evaluated. Results:Seventy-nine patients with ABC were included [mean age, 10.2 (+/- SD4.0) y, n=56 male]. The median follow-up was 5.1 years (interquartile ranges=2.5 to 8.8).Index procedure was percutaneous procedure (n=22), open procedure (n=35), or osteosynthesis alone (n=22). The median time until full weight-bearing was 13 weeks [95% confidence interval (CI)=7.9-18.1] for open procedures, 9 weeks (95% CI=1.4-16.6) for percutaneous, and 6 weeks (95% CI=4.3-7.7) for osteosynthesis alone (P=0.1). Failure rates were 41%, 43%, and 36%, respectively. Overall, 2 and 5-year failure-free survival was 69.6% (95% CI=59.2-80.0) and 54.5% (95% CI=41.6-67.4), respectively. Risk factors associated with failure were age younger than 10 years [hazard ratios (HR)=2.9, 95% CI=1.4-5.8], cyst volume >55 cm(3) (HR=1.7, 95% CI=0.8-2.5), and fracture at diagnosis (HR=1.4, 95% CI=0.7-3.3). Conclusions: As both open and percutaneous procedures along with osteosynthesis alone seem viable treatment options in this weight-bearing location, optimal treatment for proximal femoral ABCs remains unclear. The aim of the treatment was to achieve local cyst control while minimizing complications and ensuring that children can continue their normal activities as soon as possible. A personalized balance should be maintained between undertreatment, with potentially higher risks of pathologic fractures, prolonged periods of partial weight-bearing, or recurrences, versus overtreatment with large surgical procedures, and associated risks. Show less
Hoogervorst, L.A.; Coul, L.S. op de; Ray, A.; Witte, P.B. de; Boer, M.G.J. de 2022
The aim of this study was to review the available literature concerning Madura foot (“mycetoma”) caused by Madurella mycetomatis in immunocompromised patients. With a systematic literature search,... Show moreThe aim of this study was to review the available literature concerning Madura foot (“mycetoma”) caused by Madurella mycetomatis in immunocompromised patients. With a systematic literature search, we identified only three papers, describing a total of three immunocompromised patients. Hence, the clinical presentation and prognosis of the disease in this patient population have not yet been well described. In addition, we present a case from our institution, illustrating the complexity of the treatment of this rare disease. Although very rare in non-endemic countries, we emphasize that mycetoma should be included in the differential diagnoses of (immunocompromised) patients who have been residing in a geographical area where the disease is endemic and presenting with soft tissue inflammation of one of the extremities. Show less
Despite the high incidence of developmental dysplasia of the hip (DDH), treatment is very diverse. Therefore, the Dutch Orthopedic Society developed a clinical practice guideline with... Show moreDespite the high incidence of developmental dysplasia of the hip (DDH), treatment is very diverse. Therefore, the Dutch Orthopedic Society developed a clinical practice guideline with recommendations for optimal and uniform treatment of DDH. This article summarizes the guideline on centered DDH (i.e. Graf types 2A-C).The guideline development followed the criteria of Appraisal of Guidelines for Research and Evaluation II. A systematic literature review was performed to identify randomized controlled trials and comparative cohort studies including children <1 year with centered DDH. Articles were included that compared (1) treatment with observation, (2) different abduction devices, (3) follow-up frequencies, and (4) discontinuation methods. Recommendations were based on Grading Recommendations Assessment, Development, and Evaluation, which included the literature, clinical experience and consensus, patient and parent comfort, and costs.Out of 430 potentially relevant articles, 5 comparative studies were included. Final guideline recommendations were (1) initially observe 3-month-old patients with centered DDH, start abduction treatment if the hip does not normalize after 6-12 weeks; (2) prescribe a Pavlik harness to children <6 months with persisting DDH on repeated ultrasonography, consider alternative abduction devices for children >6 months; (3) assess patients every 6 weeks; and (4) discontinue the abduction device when the hip has normalized or when the child is 12 months.This paper presents a summary of part 1 of the first evidence-based guideline for treatment of centered DDH in children <1 year. Part 2 presents the guideline on decentered DDH in a separate article. Show less
Overbeek, C.; Kolk, A.; Witte, P.B. de; Nagels, J.; Nelissen, R.G.H.; Groot, J. de 2022
Background: Patients with Subacromial Pain Syndrome show reduced co-contraction of the teres major during abduction. Consequent insufficient humeral depressor function may contribute to painful... Show moreBackground: Patients with Subacromial Pain Syndrome show reduced co-contraction of the teres major during abduction. Consequent insufficient humeral depressor function may contribute to painful irritation of subacromial tissues and offers a potential target for therapy. A crucial gap in knowledge is whether the degree of teres major co-contraction in these patients is influenced by pain itself. To gain insight into this matter, we assessed whether relief of subacromial pain with local analgesics leads to increased adductor co-contraction in 34 patients with subacromial pain. Methods: In a single-arm interventional study with 34 patients, electromyographic activity of the latissimus dorsi, pectoralis major, teres major and deltoid was assessed during isometric force tasks in 24 directions before and after subacromial Lidocaine injection. Co-contraction was quantified using the activation ratio; range [-1 (sole antagonistic activation, i.e. co-contraction) to 1 (sole agonistic activation)]. Findings: There were no changes in activation ratio of the teres major after the intervention (Z-score:-0.6, p = 0.569). The activation ratio of the latissimus dorsi increased to 0.38 (quartiles: 0.13-0.76), indicating decreased co-contraction (Z-score: -2.0, p = 0.045). Interpretation: Subacromial analgesics led to a decrease in co-contraction of the latissimus dorsi, whereas no change in the degree of teres major co-contraction was observed. This study shows that decreased teres major co contraction in patients with subacromial pain, likely is not the consequence of pain itself, opening a window for physical therapy with training of teres major co-contraction to reduce subacromial irritation and pain. Level of evidence: Level II treatment study. Show less
Kolk, A.; Overbeek, C.L.; Witte, P.B. de; Canete, A.N.; Reijnierse, M.; Nagels, J.; ... ; Groot, J.H. de 2021
Background: Conflicting theories exist about the underlying cause of chronic subacromial pain in the middle-aged population. We aim to improve our understanding of kinematics and muscle activation... Show moreBackground: Conflicting theories exist about the underlying cause of chronic subacromial pain in the middle-aged population. We aim to improve our understanding of kinematics and muscle activation in subacromial pain syndrome to provide insight in its pathophysiology. Methods: In a cross-sectional comparison of 40 patients with subacromial pain syndrome and 30 asymptomatic controls, three-dimensional shoulder kinematics and electromyography-based co-contraction in 10 shoulder muscles were independently recorded. Glenohumeral and scapulothoracic kinematics were evaluated during abduction and forward flexion. Co-contraction was expressed as an activation ratio, specifying the relative agonistic and antagonistic muscle activity in each muscle. Findings: During abduction and forward flexion, the contribution of glenohumeral motion to elevation and glenohumeral external rotation was lower in subacromial pain syndrome (at 1200 abduction: - 9 degrees, 95% CI -14 degrees- -3 degrees; and - 8 degrees, 95% CI -13 degrees -3 degrees, respectively), and was compensated by more scapulothoracic motion. The pectoralis major's activation ratio was significantly lower (Z-score: -2.657, P = 0.008) and teres major's activation ratio significantly higher (Z-score: -4.088, P < 0.001) in patients with subacromial pain syndrome compared to the control group. Interpretation: Reduced glenohumeral elevation and external rotation in subacromial pain syndrome coincided with less teres major antagonistic activity during elevation. These biomechanical findings provide a scientific basis for intervention studies directed at stretching exercises to reduce glenohumeral stiffness in the treatment of subacromial pain syndrome, and teres major strengthening to improve humeral head depressor function. Show less
Brouwer, A.J.; Kempink, D.R.J.; Witte, P.B. de 2021
Purpose: Proximal femoral and/or pelvic osteotomies (PFPO) are associated with significant blood loss, which can be harmful, especially in paediatric patients. Therefore, considering methods to... Show morePurpose: Proximal femoral and/or pelvic osteotomies (PFPO) are associated with significant blood loss, which can be harmful, especially in paediatric patients. Therefore, considering methods to reduce blood loss is important. The purpose of this study was to examine the efficacy of tranexamic acid (TXA) in reducing intraoperative estimated blood loss (EBL) in paediatric patients undergoing a PFPO.Methods: Paediatric patients who had a PFPO between 2014 and 2019 were retrospectively reviewed. Outcome measures included patient demographics, TXA use (none, preoperative and/or intraoperative bolus, pump), EBL, transfusion rate and thromboembolic complications. Univariate and multivariate analyses were performed to assess associations between investigated outcome measures and EBL.Results: A total of 340 PFPO (263 patients) were included. Mean age at surgery was 8.0 years (so 4.3). In all, 269 patients received no TXA, 20 had a preoperative bolus, 43 had an intraoperative bolus and eight patients had other TXA regimes (preoperative and intraoperative bolus or pump). Overall, mean blood loss was 211 ml (SD 163). Multivariate analysis showed significant associations between higher EBL and higher age at surgery, male sex, higher body mass index and longer procedure time. There was a significant association between lower EBL and a preoperative TXA bolus: 66 ml (33%) less EBL compared with patients without TXA (95% confidence interval -129 to -4; p = 0.04). No thromboembolic complications were reported in any of the studied patients.Conclusion: Preoperative TXA administration is associated with a decreased EBL in PFPO. No thromboembolic events were reported. Administering TXA preoperatively appears to be effective in paediatric patients undergoing a PFPO. Show less
Overbeek, C.L.; Kolk, A.; Groot, J.H. de; Witte, P.B. de; Gademan, M.G.J.; Nelissen, R.G.H.H.; Nagels, J. 2019
Middle-aged individuals cocontract with adductor muscles during abduction. This may be crucial for counteracting deltoid forces, depressing the humerus and ensuring free passage of subacromial... Show moreMiddle-aged individuals cocontract with adductor muscles during abduction. This may be crucial for counteracting deltoid forces, depressing the humerus and ensuring free passage of subacromial tissues underneath the acromion during abduction. We questioned whether adductor co-contraction is always present, or develops during ageing, in which case it may explain the age-related character of common shoulder conditions such as Subacromial Pain Syndrome. In a cross-sectional analysis with electromyography (EMG), activation patterns of the latissimus dorsi, teres major, pectoralis major and deltoid muscle were assessed during isometric force tasks in 60 asymptomatic individuals between 21 and 60 years old. Cocontraction was expressed as the degree of antagonistic activation relative to the same muscle's degree of agonistic activation, resulting in an activation ratio between -1 and 1, where lower values indicate more cocontraction. Using linear regression analyses, we found age-related decreases in the activation ratio of the latissimus dorsi (regression estimate: -0.004, 95% CI: -0.007 to 0.0, p-value: 0.042) and teres major (regression estimate: -0.013, 95% CI: -0.019 to -0.008, p-value: < 0.001). In contrast to young individuals, middle-aged individuals showed a high degree of adductor cocontraction during abduction. This may indicate that during ageing, alterations in activation patterns are required for preserving pain-free shoulder function. Show less
Overbeek, C.L.; Kolk, A.; Nagels, J.; Witte, P.B. de; Zwaal, P. van der; Visser, C.P.J.; ... ; Groot, J.H. de 2019
