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Introduction: Hip pain in children and adolescents may become a diagnostic challenge. A wide range of causes must be considered in the deferential diagnosis. Ischiofemoral impingement (IFI) is a pathological condition defined by hip pain associated with narrowing of the ischiofemoral (IF) space. We report the case of an adolescent patient with non-traumatic quadratus femoris (QF) tear secondary to an occult IFI syndrome. To the best of our knowledge, this is the first such case reported in the literature. Case Report: A 15-year-old girl reported persisting hip pain for a month following increased physical activity. The symptoms had started a couple of days following a weekend of increased activity due to her participating in a dancing contest. Physical examination and imaging studies (standard anterior pelvis radiograph and MRI-scan) failed to reveal any pathology apart from an area of diffused edema in the IF space. Standard hematology and biochemistry laboratory tests were all within normal range. Conservative treatment for 6 months with rest and modification of physical activities failed. A new MRI scan showed partial edema resolution and marked reduction in the IF and QF spaces (12 mm and 8 mm, respectively), thus suggesting IFI, which, in turn, led to a partial rupture of the QF. The patient underwent a local infiltration of the QF with betamethasone sodium phosphate and betamethasone acetate (6+6 mg/2 ml) under CT guidance, which led to the complete resolution of all her symptoms. She remains symptoms free for 24 months. Conclusion: IFI is a rather uncommon condition in the developing skeleton. As in adults, in adolescents as well, MRI is the study of choice in cases of IFI, since it shows QF pathology and allows measurement of the IF and QF spaces, assisting physicians in establishing the right diagnosis. However, the coexistence of a QF hematoma and/or edema, may temper with the initial MRI measurements and render the diagnosis of the primary condition rat

The aim of this paper is to present the unique case of a sealed ruptured abdominal aortic aneurysm (AAA) with simultaneous type IIIb endoleak of an endovascular stent, mimicking a paravertebral retroperitoneal tumor. A 75-year-old male was referred to the tumor service of our tertiary orthopaedic department suffering from intractable low back pain with an onset of six months. He had undergone repair of an infrarenal AAA with an endovascular stent 5 years ago. Imaging studies depicted a large retroperitoneal mass adjacent to L2 and L3 vertebrae. The stent's metal cage had no signs of wear or migration. The pathology report of a CT-guided core-needle biopsy he had undergone before his referral raised suspicion about possible AAA rupture. CT-angiography confirmed the existence of a ruptured AAA, accompanied by retroperitoneal blood loss and a (possibly) failed stent. The IIIb eroded stent was openly removed and a Y-type allograft was used to repair the defect. The patient reported immediate relief and was uneventfully discharged. He demised 4 years later due to reasons unrelated to the hereby reported condition. Increased awareness is warranted when dealing with anterior lumbar spine or retroperitoneal lesions. A close cooperation between a vascular and an orthopaedic/spine surgeon must always be sought.

Bone cystic echinococcosis (CE) is a rare condition requiring a high level of suspicion during primary diagnosis. Wide excision of the lesion is the gold standard of treatment, posing however extreme challenges in certain parts of the skeleton, since it may well be accompanied by increased morbidity. We report the case of a 35-year-old Caucasian female with iliac bone CE, referred to our department (a regional referral center for the treatment of patients with musculoskeletal tumors). The patient reported gradually increasing dull pain at the right iliac fossa and antalgic gait, with an onset of approximately 5 years before her referral. Bone CE diagnosis was established based on physical examination, imaging studies, and two subsequent CT-guided core needle biopsies, performed within a period of 3 months, of which the second was diagnostic. Following a musculoskeletal tumor multidisciplinary meeting, it was decided that the optional treatment was the surgical removal of the cyst. Aiming to minimize the morbidity accompanying a wide resection of the lesion, we performed extended curettage of the lesion through a typical iliac spine approach, followed by microwave ablation of the walls of the remaining bone cavity. The remaining iliac defect was treated with the installation of polymethyl methacrylate bone cement. The patient reported immediate remission of symptoms postoperatively and was able to return to everyday activities two weeks postoperatively. She began oral treatment with albendazole on the 7th postoperative day. She remained symptom-free for a period of 25 months, until she developed a seroma at the gluteal area, which was treated with simple drainage. On her latest follow-up six months later, she remained symptom-free and was able to perform all her previous activities. Microwave ablation may serve as a useful adjuvant modality when treating patients with bone CE, in order to prevent relapse of the disease.

The treatment of metastatic bony lesions with the involvement of adjacent neurovascular structures presents a surgical challenge. We present—to the best of our knowledge—the first case of a patient suffering from a metastatic lytic lesion at the proximal tibia who underwent palliative treatment with the use of a polytetrafluoroethylene (PTFE) felt as a liner in order to preserve the adjacent vasculature and nerves. An 82-year-old female patient was diagnosed with multiple lytic bone metastases from renal cell carcinoma. One of these metastatic lesions was located at the proximal metaphysis of the left tibia. The lesion destructed the proximal metaphyseal part and the posterior cortex, and it was extending into the popliteal fossa. As a result, the patient was unable to bear weight. The patient was not fit to undergo radical operative treatment. As a means of palliative therapy, she underwent intralesional curettage and instillation of Poly-Methyl-Methacrylate (PMMA) bone cement using an alternative novel surgical technique with the use of a PTFE felt as a liner in order to protect the adjacent vasculature and nerves. This technique has proven to be successful in preventing cement leak into the popliteal cavity and efficient in allowing the patient to bear weight and walk independently until she demised 14 months later. The use of a PTFE felt as a liner, when treating lytic lesions, in order to protect the adjacent vasculature and nerves from PMMA leakage, is a helpful novel surgical option in cases when a radical treatment cannot be implemented.

Aim of this study was to investigate the potential influence of Critical Shoulder Angle (CSA) as a predisposing factor for the development of degenerative full-thickness rotator cuff tears (DRCT) or primary glenohumeral osteoarthritis (PGOA). A systematic review of the Pubmed, Scopus, Mendeley, ScienceDirect and the Cochrane Central Register of Controlled Trials online databases was performed for literature regarding CSA and its association with DRCT and PGOA. In order to evaluate solely the relationship between CSA as a predisposing factor for the development of the aforementioned degenerative shoulder diseases (DSDs), we precluded any study in which traumatic cases were not clearly excluded. Our search strategy identified 289 studies in total, nine of which were eligible for inclusion based on our pre-established criteria. Quality assessment contacted using the Newcastle Ottawa Scale for case-control studies. There were a total of 998 patients with DRCT and 285 patients with PGOA. The control groups consisted of a total of 538 patients. The mean CSA ranged from 33.9° to 41.01° for the DRCT group, from 27.3° to 29.8° for the PGOA group and from 30.2° to 37.28° for the control group. All studies reported statistically significant differences between the DRCT and PGOA groups and the respective control groups. Our study results showed that there is moderate evidence in the literature supporting an intrinsic role of CSA in the development of DSDs. Level of evidence: IV. Systematic review of diagnostic studies, Level II-IV.

Only three cases of patients suffering from a localized chronic form of Langerhans cell histiocytosis (LCH) successfully treated with radiofrequency ablation (RFA) have been published so far. This is the first case report of a patient with a localized chronic form of LCH of the femur, which was successfully treated with percutaneous image-guided RFA, and who was evaluated pre-RFA and followed up post-RFA for a period of 48 months, in order to validate the safety and efficacy of this method and to obtain imaging studies depicting the actual in situ changes taking place post-RFA. RFA was proved to be a safe and efficient method when treating patients with a localized chronic form of LCH.

BACKGROUND: Alpha-tocopherol, a well-known antioxidative agent, may have a positive effect on bone formation during the remodeling phase of secondary fracture healing. Fracture healing and osseointegration of implants share common biological pathways; hence, alpha-tocopherol may enhance implant osseointegration. QUESTIONS/PURPOSES: This experimental study in rats assessed the ability of alpha-tocopherol to enhance osseointegration of orthopaedic implants as determined by (1) pull-out strength and removal torque and (2) a histomorphological assessment of bone formation. In addition, we asked, (3) is there a correlation between the administration of alpha-tocopherol and a reduction in postoperative oxidative stress (as determined by malondialdehyde, protein carbonyls, reduced and oxidized glutathione and their ratio, catalase activity and total antioxidant capacity) that develops after implantation of an orthopaedic implant? METHODS: This blinded study was performed in study and control groups, each consisting of 15 young adult male Wistar rats. On Day 0, a custom-designed stainless-steel screw was implanted in the proximal metaphysis of both tibias of all rats. On Day 1, animals were randomized to receive either alpha-tocopherol (40 mg/kg once per day intraperitoneally) or saline (controls). Animals were treated according to identical perioperative and postoperative protocols and were euthanized on Day 29. All animals completed the study and all tibias were suitable for evaluation. Implant pullout strength was assessed in the right tibias, and removal torque and histomorphometric evaluations (that is, volume of newly formed bone surrounding the implant in mm(3), percentage of newly formed bone, percentage of bone marrow surrounding the implant per optical field, thickness of newly formed bone in μm, percentage of mineralized bone in newly formed bone, volume of mature newly formed bone surrounding the implant in mm(3) and percentage of mineralized newly formed bone per tissue area) were performed in the left tibias. The plasma levels of alpha-tocopherol, malondialdehyde, protein carbonyls, glutathione, glutathione disulfide, catalase, and the total antioxidant capacity were evaluated, and the ratio of glutathione to oxidized glutathione was calculated. RESULTS: All parameters were different between the alpha-tocopherol-treated and control rats, favoring those in the alpha-tocopherol group. The pullout strength for the alpha-tocopherol group (mean ± SD) was 124.9 ± 20.7 newtons (N) versus 88.1 ± 12.7 N in the control group (mean difference -36.7 [95% CI -49.6 to -23.9]; p < 0.001). The torque median value was 7 (range 5.4 to 8.3) versus 5.2 (range 3.6 to 6 ) N/cm (p < 0.001). The newly formed bone volume was 29.8 ± 5.7 X 10(-3) versus 25.2 ± 7.8 X 10(-3) mm(3) (mean difference -4.6 [95% CI -8.3 to -0.8]; p = 0.018), the percentage of mineralized bone in newly formed bone was 74.6% ± 8.7% versus 62.1% ± 9.8% (mean difference -12.5 [95% CI -20.2 to -4.8]; p = 0.003), the percentage of mineralized newly formed bone per tissue area was 40.3 ± 8.6% versus 34.8 ± 9% (mean difference -5.5 [95% CI -10.4 to -0.6]; p = 0.028), the glutathione level was 2 ± 0.4 versus 1.3 ± 0.3 μmol/g of hemoglobin (mean difference -0.6 [95% CI -0.9 to -0.4]; p < 0.001), the median glutathione/oxidized glutathione ratio was 438.8 (range 298 to 553) versus 340.1 (range 212 to 454; p = 0.002), the catalase activity was 155.6 ± 44.6 versus 87.3 ± 25.2 U/mg Hb (mean difference -68.3 [95% CI -95.4 to -41.2]; p < 0.001), the malondialdehyde level was 0.07 ± 0.02 versus 0.14 ± 0.03 μmol/g protein (mean difference 0.07 [95% CI 0.05 to 0.09]; p < 0.001), the protein carbonyl level was 0.16 ± 0.04 versus 0.27 ± 0.08 nmol/mg of protein (mean difference -0.1 [95% CI 0.05 to 0.15]; p = 0.002), the alpha-tocopherol level was 3.9 ± 4.1 versus 0.9 ± 0.2 mg/dL (mean difference -3 [95% CI -5.2 to -0.7]; p = 0.011), and the total antioxidant capacity was 15.9 ± 3.2 versus 13.7 ± 1.7 nmol 2,2-diphenyl-1-picrylhydrazyl radical/g of protein (mean difference -2.1 [95% CI -4.1 to -0.18]; p = 0.008). CONCLUSIONS: These results using an in vivo rat model support that postoperatively administered alpha-tocopherol can enhance the osseointegration of an orthopaedic implant, although a cause and effect relationship between the administration of alpha-tocopherol and a reduction in postoperative stress cannot be securely established. CLINICAL RELEVANCE: These findings suggest that postoperative administration of alpha-tocopherol is a promising approach to enhance osseointegration of orthopaedic implants in patients. Further studies with different animal models and/or different implants and those evaluating the alpha-tocopherol dose response are needed before performing clinical trials that will examine whether these promising, preliminary results can be extrapolated to the clinical setting as well.

We present final results of a study comparing teriparatide 20 μg every day (QD) with risedronate 35 mg once per week (QW) started within 2 weeks after surgery for a pertrochanteric hip fracture. Patients with BMD T-score ≤ -2.0 and 25OHD ≥9.2 ng/mL were randomized to receive 26-week double-dummy treatment plus calcium and vitamin D, followed by 52-week open-label treatment with the same assigned active drug. Primary endpoint was change from baseline in lumbar spine (LS) BMD at 78 weeks. Secondary and exploratory endpoints were change in BMD at the proximal femur, function, hip pain (Charnley score and 100 mm Visual Analog Scale [VAS]), quality of life (Short Form-36), radiology outcomes, and safety. Data were analyzed with mixed models for repeated measures (MMRM) and logistic regression. Totally, 224 patients were randomized; 171 (teriparatide: 86) contributed to the efficacy analyses (mean ± SD age: 77 ± 7.7 years, 77% females). Mean baseline LS, femoral neck (FN), and total hip (TH) T-scores were -2.16, -2.63, and -2.51, respectively. At 78 weeks, BMD increased significantly more with teriparatide compared to risedronate at the LS (+11.08% versus +6.45%; p < 0.001) and FN (+1.96% versus -1.19%; p = 0.003), with no significant between-group difference in TH BMD. Timed up-and-go (TUG) test was significantly faster with teriparatide at 6, 12, 18, and 26 weeks (differences: -3.2 to -5.9 s; p = 0.045 for overall difference). Hip pain during TUG test by 100 mm VAS was significantly lower with teriparatide at 18 weeks (adjusted difference: -11.3 mm, p = 0.033; -10.0 and -9.3 mm at 12 and 26 weeks, respectively; p = 0.079 for overall difference). Other secondary and exploratory outcomes were not different. Teriparatide group showed two new hip fractures versus seven with risedronate (p = 0.171) and more frequent hypercalcemia and hyperuricemia. In conclusion, 78-week treatment with teriparatide showed significantly greater increases in LS and FN BMD, less pain, and a faster TUG test versus risedronate. © 2016 American Society for Bone and Mineral Research.

Objectives Determination of the serum levels of Receptor Activator of Nuclear Factor-Κb Ligand, bone-specific alkaline phosphatase, osteocalcin and osteoprotegerin in patients suffering from osteoarthritis of varying severity and healthy controls and correlation of these results with the patients' age and the radiographically assessed severity of the disease. Design and methods Patients suffering from hip ( n = 58) or knee ( n = 117) osteoarthritis and matched controls ( n = 19) were enrolled in this study. Patients underwent physical examination and standard radiographic evaluation before blood sampling. Results The serum levels of osteoprotegerin were positively correlated with age in all groups, whereas those of osteocalcin in the ‘knee’ group only. Osteoarthritis' severity and location did not have a statistically significant impact on the mean serum level of any marker in both groups. Conclusions Based on our results, none of the studied markers can serve as a surrogate for radiographic imaging in patients suffering from hip and knee osteoarthritis.

Study design Cross-sectional observational study. Objective Evaluation and comparison of the prevalence of adolescent idiopathic scoliosis (AIS) among 2 groups of patients (athletes and nonathletes) to determine whether athletic activities are related to the development of AIS. Summary of background data The potential association between AIS and exercising remains uncertain. The latter has often been considered as a therapeutic means and a causative factor of the former. Methods A group of 2387 adolescents (boys: 1177, girls: 1210, mean age: 13.4 years) was evaluated. All completed a questionnaire concerning personal, somatometric, and secondary sex characteristics, type, duration and character of daily-performed physical activities, and existing cases of AIS among relatives. Patients were classified into 2 groups according to their answers; "athletes" and "nonathletes." The groups were comparable as far as age, height, weight, onset of menstruation, family history of scoliosis, and side of handedness were concerned. Children underwent physical examination by 3 orthopedic surgeons who were unaware of their level of athletic activities. Children considered, by all, to be suspicious of suffering from scoliosis, underwent further radiographic evaluation. Results In 99 cases (athletes: 48, nonathletes: 51), AIS was radiographically confirmed (Cobb angle >10 degrees). No statistically significant difference was found between athlete and nonathlete adolescents (P = 0.842), athlete and nonathlete boys (P = 0.757), and athlete and nonathlete girls (P = 0.705), as far as the prevalence of AIS was concerned. The mean value of the Cobb angle of the main scoliotic curve was not statistically different between male athletes and nonathletes (P = 0.45) and female athletes and nonathletes (P = 0.707). With the Cobb threshold reset at 20 degrees, no statistically significant differences were detected either. Conclusion Our results demonstrate that systematic exercising is probably not associated with the development of AIS. Actively participating in sports activities doesn't seem to affect the degree of the main scoliotic curve either.

Study design The report of 2 cases and review of the literature. Objective To report the cases of a pair of female monozygotic (high-class athletes) twins discordant for adolescent idiopathic scoliosis. Summary of background data The relation between scoliosis and exercising is rather unclear. The latter has often been considered both as a therapeutic means and a causative factor of the former. The existence of genetic predisposition in the development of adolescent idiopathic scoliosis is commonly accepted. According to the best of our knowledge, this is the first report of a pair of female monozygotic (high-class athletes) twins, discordant for adolescent idiopathic scoliosis. METHODS.: A pair of 13.5-year-old female monozygotic twins, high-class level athletes of synchronized swimming, was clinically examined during a school screening program. Both girls were observed in the standing erect position for asymmetries of the lateral contours of the trunk, shoulders, and scapulas and their limb's length was measured. The "forward bending test" was performed to determine the existence of rib hump asymmetry. Results One of the sisters was considered to be suspicious of suffering from scoliosis. The radiologic evaluation that followed confirmed the existence of adolescent idiopathic scoliosis (left thoracolumbar curve of 32 degrees as measured by the Cobb angle). The clinical and radiologic evaluation of her sibling failed to reveal the existence of any spinal deformity. Conclusion Adolescent idiopathic scoliosis seems to be a multifactorial skeletal disorder. The role of exercising and heredity in its development remain controversial.

BACKGROUND: Osteoporosis drugs might affect fracture-healing. We therefore studied the effects of teriparatide in comparison with risedronate on recovery after pertrochanteric hip fractures.METHODS: The study was a randomized, multicenter, active-controlled, 78-week trial comparing teriparatide (20 μg/day) with risedronate (35 mg/week) initiated within 2 weeks after fixation of a low-trauma pertrochanteric hip fracture (AO/OTA 31-A1 or 31-A2). The main inclusion criteria were a bone mineral density T-score of ≤-2.0 and 25-OH-vitamin D of ≥9.2 ng/mL. During the first 26 weeks, patients received study medication with oral or injectable placebo plus calcium and vitamin D in a double-blinded fashion. Secondary (Timed Up-and-Go [TUG] test, hip pain, Short Form [SF]-36 health status, and safety) and exploratory (radiographic outcomes and ability to walk) 26-week end points are reported.RESULTS: Of the 224 patients who were randomized, 171 (86 teriparatide, 85 risedronate) were included in the analysis. The mean age was 77 ± 8 years, 77% were female, and 26% had a prior history of low-trauma fracture. The teriparatide group completed the TUG test in a shorter time at 6, 12, 18, and 26 weeks (differences of -5.7, -4.4, -3.1, and -3.1 seconds, respectively; p = 0.021 for the overall difference). They also reported less pain on a visual analog scale immediately after the TUG test at 12 and 18 weeks (adjusted absolute differences of 10.6 and 11.9 mm, respectively; p < 0.05). There were no significant between-group differences in the SF-36 score, Charnley hip pain score, ability to walk, or use of walking aids during follow-up. Radiographic healing at 6, 12, and 26 weeks, mechanical failure of the implant (teriparatide, 7; risedronate, 8), loss of reduction (teriparatide, 2; risedronate, 4), and nonunion (0 cases) were not significantly different. Mild hypercalcemia and hyperuricemia were more frequent with teriparatide.CONCLUSIONS: Teriparatide was associated with less pain and a shorter time to complete the TUG test between 6 and 26 weeks compared with risedronate. Other fracture-recovery outcomes were similar. The results should be interpreted with caution as these were secondary end points.LEVEL OF EVIDENCE: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Injuries to the lateral part of the clavicle in a child with an immature skeleton are more likely to be physeal fractures than true acromioclavicular separations1,2. Nevertheless, lateral physeal separations of the clavicle and acromioclavicular joint dislocations do occur in children, and Dameron and Rockwood have classified these injuries according to six distinct types3. The combination of a physeal fracture with a ligamentous injury is even rarer and seems to violate the basic principle that a bone will fracture before a ligament will rupture in a child2. The aim of this case report is to remind the reader that, although this type of combined lesion can occur, it is often misdiagnosed or overdiagnosed; thus, an appropriate and careful evaluation must be performed so that unnecessary treatment can be avoided2. We report the case of a twelve-year-old boy who sustained an injury to the left acromioclavicular joint as a result of a fracture of the lateral part of the clavicle and a complete rupture of the coracoclavicular ligaments. This type of injury could not be categorized as any of the types in the classification system of Dameron and Rockwood3. This study was approved by the scientific review board at our hospital and was conducted in accordance with the World Medical Association Declaration of Helsinki of 1964, as revised in 1983. The parents of our patient were informed that data concerning the case would be submitted for publication, and they consented. Fig. 1 Standard anteroposterior radiograph of the left shoulder. Note the increased distance between the clavicle and both the acromion and the coracoid process. Fig. 2 The three-dimensional reconstruction of the computed tomography scan confirmed the fracture of the clavicle and …

Bone disease is present in the majority of patients with multiple myeloma and can seriously affect quality of life and survival rate. In addition to suppression of osteoclastogenesis, there have been developments made in terms of the therapeutic agents available, such as novel immunomodulating agents, proteasome and receptor activator of nuclear factor κB ligand inhibitors.AREAS COVERED include in vitro, in vivo and clinical evidence was collected using MEDLINE (1950 - May 2014), EMBASE (1980 - May 2014) and Google Scholar (1980 - May 2014) databases.Bisphosphonates are the mainstay of myeloma bone disease treatment. Oral clodronate and intravenous pamidronate and zoledronic acid are currently used drugs and seem to have comparable results in preventing skeletal-related events of the disease. Zoledronate can also have survival benefits and based on the available evidence is the superior bisphosphonate; however, its side effects have to be monitored. Denosumab had comparable results with zoledronate on myeloma bone disease treatment; its use has not been completely proven yet. There is an expanding set of drugs, proteasome inhibitors, under investigation with great potential to reduce the negative effects of myeloma cells on bone. Future clinical studies should compare both the catabolic and anabolic effects of these agents on bone.

Purpose. To compare the measured resection technique and the gap balancing technique for correction of the femoral rotational alignment. Methods. 57 women and 6 men (mean age, 70 years) with end-stage osteoarthritis and ±15° malalignment and ±10° flexion contracture of the knee underwent primary total knee arthroplasty through the medial approach using the measured resection technique (n=34) or the gap balancing technique (n=29). Femoral rotational alignment was evaluated before and 7 days after surgery using computed tomography by referencing the 2 posterior condyles to the transepicondylar axis. Results. The 2 groups did not differ significantly in terms of correction of the femoral rotational alignment (3.4°±1.4° vs. 3.5°±3.1°, p=0.817). Conclusion. The measured resection and the gap balancing techniques achieved comparable correction of femoral rotational alignment.

Background The melatonin deficiency hypothesis as a central mechanism in the pathogenesis of adolescent idiopathic scoliosis (AIS) is certainly intriguing. However, the actual role of melatonin remains unclear. The aim of this study was to assess the potential clinical value of melatonin serum level in the pathogenesis and the prognosis of AIS progression in patients who were treated nonoperatively. Methods Two groups of patients were enrolled. The study group consisted of patients with AIS aged below 14 years who were treated conservatively. In the second group, that is, the control group, age-matched, weight-matched, and height-matched healthy individuals were enrolled. Blood samples were collected from all patients on visit 1 and the serum levels of melatonin were evaluated with the enzyme-linked immunosorbent assay (ELISA) method. The blood sampling procedure was repeated exactly 1 year later (visit 2). Results Forty-two patients formed the study group (with AIS) and 29 served as the control group. The mean serum value of melatonin on visit 1 was 19.32 pg/mL for the AIS group and 12.23 pg/mL for the control group. This difference was statistically significant (P = 0.014). One year later, 34 patients from the AIS group and 23 from the control group were reevaluated and the mean serum levels of melatonin were 52.43 and 68.44 pg/mL, respectively. No statistically significant difference was found between the 2 groups (P = 0.235). Statistical analysis of the serum melatonin levels of patients with progressing AIS (>5 degrees of the Cobb angle in 1 y) when compared with patients with stable AIS (P = 0.387) or the control group (P = 0.727) failed to show that the deficiency of melatonin may be associated with the progression of AIS. Conclusions Higher melatonin levels were observed in conservatively treated patients with AIS, whereas melatonin deficiency was not associated with AIS progression in this study. Level of evidence Level III-case-control study.

Purpose. To evaluate the incidence of secondary hyperparathyroidism (SH) among postmenopausal women with end-stage knee osteoarthritis scheduled for total knee replacement (TKR). Methods. 283 Caucasian postmenopausal women aged 49 to 81 (mean, 70) years with end-stage idiopathic knee osteoarthritis were scheduled to undergo primary TKR. They had been menopausal for 7 to 31 (mean, 19) years. Their preoperative serum levels of intact parathyroid hormone (I-PTH), calcium, phosphorus, creatinine, and the clearance of creatinine were evaluated. Results. 100 patients had abnormally elevated serum I-PTH. The overall incidence of SH was 35%. Serum levels of calcium and phosphorus were elevated in 33 and 12 patients, respectively. The serum level of I-PTH correlated positively with patient age ( r=0.158, p=0.008) and serum creatinine level ( r=0.138, p=0.021) and negatively with clearance of creatinine ( r= −0.169, p=0.004). Conclusion. SH is common among elderly postmenopausal women and may affect bone healing and implant fixation. Preoperative screening/evaluation of the serum PTH level in postmenopausal women scheduled for TKR is recommended.

Purpose. To evaluate short-term parathyroid hormone (PTH) secretion following total knee arthroplasty (TKA). Methods. 119 Caucasian postmenopausal women aged 49 to 81 (mean, 69.8) years who underwent TKA for end-stage knee osteoarthritis were included. Serum levels of intact-PTH, calcium, phosphorus, and creatinine were evaluated pre- and post-operatively (on days −1 and 7). Creatinine clearance was also calculated. Results. In 67 of the patients, serum intact-PTH levels decreased after TKA; this sample proportion was not significant (p=0.82). In 16 of the patients, such levels elevated abnormally (above normal range). In the remaining 36 patients, such levels elevated within the normal range. Therefore, the mean serum intact-PTH level of all patients increased slightly after TKA (45.4 vs. 45.3, p=0.162). The serum intact-PTH level did not correlate to body weight ( r=–0.045, p=0.624), patient age ( r=–0.061, p=0.508), serum creatinine level ( r=0.084, p=0.366), and clearance of creatinine ( r=–0.037, p=0.692). Conclusion. In most postmenopausal women, the serum intact-PTH level decreased moderately following TKA, but in some, the level was abnormally elevated. This may interfere the prosthesis incorporation process.

Participation in physical activity and recreational sports is critical for maintaining overall health; athletic activities and reduction in the incidence of several "lifestyle" diseases seem to have a dose-dependent relationship. Also, quality of life is enhanced in people who are active and regularly participate in sports. However, sports-related joint loading and strenuous occupational loading have been shown to increase the risk of osteoarthritis (OA), which seems to have a multifactorial etiology. This article reviews the literature on known connections between participation in sports and athletic activities and development of secondary OA in the joints of the major upper and lower limbs (ie, knee, hip, elbow, and shoulder) in athletes without injury. Most studies examining the connection between participation in sports and later development of OA usually provide low-level evidence and have many methodological weaknesses. Based on the literature reviewed in this article, it may be concluded that the connection between participation in athletic activities and development of OA has not been proven; however, the condition is highly likely to occur in the hip and knee joints. Definite conclusions regarding the connection between development of glenohumeral and/or elbow OA and participation in athletic activities cannot be drawn.

Background Radial head fractures often pose therapeutic dilemmas. We present the early results of patients who underwent radial head replacement with the MoPyC prosthesis (Bioprofile, Tornier, Saint-Ismier, France). Materials and methods We re-evaluated patients who underwent post-traumatic radial head resection and implantation of the MoPyC prosthesis due to pain and motion restriction. All patients underwent radiographic evaluation. Clinical evaluation was performed using the Broberg-Morrey and the Mayo Elbow Performance Score (MEPS) scales. Results Thirty-two patients (20 men, 12 women; mean age, 54 years; 22 dominant upper limbs) were evaluated. Twenty had a comminuted radial head fracture (Mason IV, 15; Mason III, 5), 2 from radial head fracture malunion, and 10 had complex elbow injuries (comminuted radial head fractures with ligamentous ruptures with or without coronoid process fractures). Mean follow-up was 27 months (range, 21-46 months). The mean results at the latest follow-up were flexion–extension, 130° (range, 105°-150°); pronation, 74° (range, 60°-80°); and supination, 72° (range, 60°-80°). No laxity was evident during valgus and varus stress tests. Mean grip strength was 96% of the contralateral side. Broberg-Morrey scores were excellent in 33%, good in 44%, and fair in 23%. MEPS results were excellent in 80%, good in 17%, and fair in 3%. There were 6 cases of periprosthetic lucencies or osteolysis of the radius without any clinical signs of loosening. Conclusions Radial head replacement with the MoPyC pyrocarbon prosthesis (when performed in carefully selected patients) yields satisfactory results regarding range of motion and function of the elbow joint.

The potential relationship between adolescent idiopathic scoliosis (AIS) and sports is rather vague. Sports have often been considered to be a causative factor of, or a treatment option for the former, particularly among adolescent athletes who are engaged in certain athletic activities. The highly repetitive nature of sports, amenorrhea, exercise-related exerted stress on the immature spine of professional adolescent athletes, and the joint laxity that may coexist during adolescence, have also been associated with an increased incidence of AIS. The purpose of this article is to discuss the potential connection between sports and AIS by reviewing the existing literature.

The biological problems related to wear debris after total hip arthroplasty have stimulated renewed interest in alternatives to metal-on-polyethylene bearing surfaces.We retrospectively evaluated the clinical and radiographic results of 100 patients who had undergone a total of 109 primary total hip arthroplasties with a cementless alumina ceramic-on-ceramic prosthesis between January 1985 and December 1989. The mean age of the patients at the time of the index arthroplasty was forty-six years. Clinical evaluation was performed with use of the Charnley modification of the Merle d'Aubigné-Postel scale. Seventy-eight patients who had had a total of eighty-five arthroplasties were available for follow-up evaluation at an average of 20.8 years. The patients' average age at the time of the latest follow-up was 66.8 years.Six hips (six acetabular cups and one femoral stem) in six patients underwent revision. Aseptic loosening of the cup combined with focal osteolysis was the cause of all six revisions. In one patient, the stem was also revised because of aseptic loosening. At the time of final follow-up, the result was excellent (according to the Merle d'Aubigné-Postel scale) in 68% of the hips, good in 19%, fair in 9%, and poor in 4%. The mean Merle d'Aubigné-Postel score improved from 7.9 points preoperatively to 16.9 points postoperatively (p0.001). The cumulative rate of survival of the prostheses was 84.4% at 20.8 years.The results of these cementless ceramic-on-ceramic total hip arthroplasties continued to be satisfactory at a minimum of twenty years postoperatively. The improved design of contemporary prostheses and the new generation of ceramic-on-ceramic bearing surfaces may lead to even better long-term results.

BACKGROUND: Pantalar arthrodesis is considered by many to be the final operative option before amputation for the treatment of paralytic foot deformities. The aim of the present study was to evaluate the long-term results of pantalar arthrodesis with regard to its impact on the adjacent joints and the walking ability of patients with paralytic foot deformities. METHODS: Twenty-four patients (seventeen men and seven women) who underwent a one-stage pantalar arthrodesis between 1953 and 1973 for the treatment of sequelae of poliomyelitis were reevaluated. All patients underwent a physical and radiographic examination, and all completed the Short Form-36 questionnaire and a pantalar arthrodesis-specific questionnaire. RESULTS: The average age of the patients was twenty years at the time of the operation and 57.2 years at the time of the latest evaluation. The average duration of follow-up was 37.2 years. Eleven patients had development of immediate postoperative complications, including wound-healing problems (nine) and infections (two). The long-term results, however, were good (mean Short Form-36 scores, 73 of 100 points [overall], 51.5 points [physical functioning], and >70 points [all other domains]). Sixteen patients experienced repeated episodes of ipsilateral knee pain; most (fifteen) of these patients experienced a gradual onset of this pain, starting at an average of 20.8 years (range, fifteen to thirty years) postoperatively. The position of the fused ankle did not appear to have a significant impact on the development of ipsilateral knee pain or the time interval between the pantalar arthrodesis and the onset of ipsilateral knee pain. CONCLUSIONS: Pantalar arthrodesis effectively stabilizes the ankle, hindfoot, and midfoot in patients with severe paralytic deformities. Even though most patients can be expected to have development of osteoarthritis of the ipsilateral knee, it seems that a successfully performed pantalar arthrodesis in carefully selected cases is a reliable operative option offering a strong and stable foot that will function well for many years. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence. ORIGINAL ABSTRACT CITATION: “The Role of Pantalar Arthrodesis in the Treatment of Paralytic Foot Deformities. A Long-Term Follow-up Study” (2009;91:575-83).

Background: There are several methods to reduce anterior shoulder dislocations, but few studies have compared the efficacy, safety, and reliability of the different techniques. As a result, deciding which technique to use is seldom based on objective criteria. The aim of the present study was to introduce a new method to reduce an anterior shoulder dislocation, which we have termed “FARES” (Fast, Reliable, and Safe), and to compare it with the Hippocratic and Kocher methods in terms of efficacy, safety, and the intensity of pain felt by the patient during reduction. Methods: Between September 2006 and June 2008, a total of 173 patients with an acute anterior shoulder dislocation (with or without a fracture of the greater tuberosity) were enrolled in the study. One hundred and fifty-four patients, who met all inclusion criteria, were randomly assigned to one of the three study groups (FARES, Hippocratic, and Kocher) and underwent reduction of the dislocation by first or second-year orthopaedic surgery residents. A visual analog scale was used to determine the intensity of the pain felt by the patient during reduction. Results: Demographically, the groups were comparable in terms of age, male:female ratio, the mechanism of dislocation, and the mean time between the injury and the first attempt at reduction. Reduction was achieved with the FARES method in 88.7% of the patients, with the Hippocratic method in 72.5%, and with the Kocher method in 68%. This difference was significant, in favor of the FARES method (p = 0.033). The mean duration of the reduction maneuver was significantly shorter for the FARES method (2.36 ± 1.24 minutes for the FARES method, 5.55 ± 1.58 minutes for the Hippocratic method, and 4.32 ± 2.12 minutes for the Kocher method; p < 0.001), and the mean visual analog pain score was significantly lower for the FARES method (1.57 ± 1.43 for the FARES method, 4.88 ± 2.17 for the Hippocratic method, and 5.44 ± 1.92 for the Kocher method; p < 0.001). No complications were noted in any group. Conclusions: The FARES method is a significantly more effective, faster, and less painful method of reduction of an anterior shoulder dislocation in comparison with the Hippocratic and Kocher methods. It is easily performed by only one physician, it is applicable to anterior shoulder dislocations as well as simple fracture-dislocations, and its use is associated with no more morbidity than that associated with the other two methods. Level of Evidence: Therapeutic Level I. See Instructions to Authors for a complete description of levels of evidence.

Study design Prospective, double-blind, randomized, case-control study. Objective To evaluate the efficacy of caudal epidural injections (CEI) containing steroid versus nonsteroid preparations when treating patients suffering from low back pain (LBP) and sciatica. Summary of background data Literature seems to be deprived of well-designed randomized, controlled studies that evaluate the effectiveness of CEI in the treatment of chronic LBP; hence the value of CEI remains still the subject of controversy. Methods Patients suffering from severe chronic LBP and sciatica were randomly allocated into 2 groups. Steroid-group's patients (n = 93) underwent CEI containing 12 mL of xylocaine 2% and 1 mL of betamethasone dipropionate and betamethasone phosphate (2 + 5) mg/dL. Water for Injection (WFI)-group's patients (n = 90) underwent CEI containing 12 mL of xylocaine 2% and 8 mL of WFI. Both groups were statistically comparable as far as their demographic data and the cause and duration of symptoms were concerned. Patients answered the Oswestry Disability Index questionnaire and underwent physical examination, before and at 1 week, 1 month, 6 months, and 1 year following the CEI. Results Symptoms improved in 132 patients (72.1%) following CEI. The mean Oswestry Disability Index questionnaire score of steroid-group's patients was statistically significant lower than that of the WFI-group at all postinjection re-evaluations. Patients receiving steroid CEI experienced faster relief during the first postinjection week. The Straight Leg Rising test improved in both groups following CEI; this improvement was faster among steroid-group's patients. Fifty-one patients (27.8%), noticed no improvement 1 week post-CEI and underwent a second CEI (with the same preparation) 7 to 14 days later. Nineteen of them reported improvement; 32 (steroid-group:13, WFI-group:19) did not respond well and underwent operative decompression (n = 15) or spinal fusion (n = 17). Conclusion CEI containing local anesthetic and steroids or WFI seems to be effective when treating patients with LBP and sciatica. CEI containing steroid preparations demonstrated better and faster efficacy.

Background: Pantalar arthrodesis is considered by many to be the final operative option before amputation for the treatment of paralytic foot deformities. The aim of the present study was to evaluate the long-term results of pantalar arthrodesis with regard to its impact on the adjacent joints and the walking ability of patients with paralytic foot deformities. Methods: Twenty-four patients (seventeen men and seven women) who underwent a one-stage pantalar arthrodesis between 1953 and 1973 for the treatment of sequelae of poliomyelitis were reevaluated. All patients underwent a physical and radiographic examination, and all completed the Short Form-36 questionnaire and a pantalar arthrodesis-specific questionnaire. Results: The average age of the patients was twenty years at the time of the operation and 57.2 years at the time of the latest evaluation. The average duration of follow-up was 37.2 years. Eleven patients had development of immediate postoperative complications, including wound-healing problems (nine) and infections (two). The long-term results, however, were good (mean Short Form-36 scores, 73 of 100 points [overall], 51.5 points [physical functioning], and >70 points [all other domains]). Sixteen patients experienced repeated episodes of ipsilateral knee pain; most (fifteen) of these patients experienced a gradual onset of this pain, starting at an average of 20.8 years (range, fifteen to thirty years) postoperatively. The position of the fused ankle did not appear to have a significant impact on the development of ipsilateral knee pain or the time interval between the pantalar arthrodesis and the onset of ipsilateral knee pain. Conclusions: Pantalar arthrodesis effectively stabilizes the ankle, hindfoot, and midfoot in patients with severe paralytic deformities. Even though most patients can be expected to have development of osteoarthritis of the ipsilateral knee, it seems that a successfully performed pantalar arthrodesis in carefully selected cases is a reliable operative option offering a strong and stable foot that will function well for many years. Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

Hip fusion has served well for many years as the surgical procedure of choice to treat painful joints with severe osteoarthritis or tuberculous arthritis. This retrospective study evaluates the long-term results of hip fusion, as far as its impact on the adjacent joints is concerned. Thirty-three patients that underwent hip arthrodesis 26-52 years previously were evaluated. All patients reported being satisfied with the fusion and being able to adequately work and perform everyday activities. Twenty-five reported episodes of low back-pain, 18 reported pain in the ipsilateral knee, four in the contralateral knee and five in the contralateral hip. Back pain started after an average time interval of 24 years, and pain in the ipsilateral knee appeared 24.6 years after the fusion. Hip fusion, a procedure which is now hardly ever performed, appears to offer a painless, strong and stable hip. However, the adjacent joints, mainly the lumbosacral spine and the ipsilateral knee, will probably develop secondary degenerative arthritis.

Background Being the result of high-energy trauma in most cases, traumatic sacral fractures are rare, difficult to recognise and frequently misdiagnosed. Furthermore they may lead to vascular injuries, mechanical instability, neurological impairment and increased morbidity. As a result, patients with traumatic sacral fractures may suffer major socio-economic consequences. Objective This retrospective case-series study evaluated the functional, neurological, mental and emotional status of patients who had suffered traumatic sacral fractures and either followed conservative or underwent operative treatment at our department. Patients and methods We evaluated the clinical and radiographic results of all patients who had suffered traumatic sacral fractures between December 2003 and June 2007. The case-notes of all patients were reviewed, all co-existing injuries were registered and an ISS was calculated for each patient. At the latest follow-up visit, all patients completed the Short Form-36 questionnaire as well. Results Sixteen patients (eleven male, five female) were included in this study. At the time of initial admission, the mean age of the patients was 30 years (range: 14–53) and the mean ISS was 33.2 points (range: 21–59). The mean follow-up period was 24.1 months (range: 13–40). Six patients were treated operatively (four patients diagnosed with some type of neurological impairment at their initial physical examination and two patients due to pelvic instability). The mean ISS of the patients who were treated operatively was 41.1 points (range: 21–59), whereas of those who were treated conservatively was 28.5 points (range: 21–45). No patient had any neurological deficit at his/her latest re-evaluation. Patients who were treated conservatively achieved the best scores in every domain of the SF-36 questionnaire, when compared with those who were treated operatively. Conclusion The diagnosis and management of sacral fractures may pose several dilemmas in everyday's clinical praxis. Patients suffering from traumatic sacral fractures who were treated conservatively seem to have better functional and mental/emotional outcomes, probably because their injuries were less severe than those of the patients who were treated conservatively.

We present the results of combined, simultaneous application of sclerotherapy and rubber band ligation during one session in patients with symptomatic second-degree haemorrhoids. Between 1993 and 1996, 83 consecutive outpatients with second-degree haemorrhoids underwent simultaneous rubber band ligation of larger (primary) piles and sclerotherapy of smaller (secondary) piles. The treatment was successful, and the symptoms were controlled in 88% of the patients. The overall incidence of complications was 9.2%, but these were minor and transient. The simultaneous, combined sclerotherapy and rubber band ligation of second-degree haemorrhoids is a simple, safe, and effective method, with only minor and transient complications.

A rare case of bursal osteochondromatosis overlying an osteochondroma located at the proximal third of the left tibia in a 10-year-old boy is described. The treatment was operative by marginal resection of the affected bursa and marginal en bloc resection of the osteochondroma. The patient remains symptom and complication free 8 years postoperatively with no sign of recurrence of both lesions. This is the first reported case of a bursal osteochondromatosis overlying an osteochondroma in a developing skeleton, thus rendering this type of lesion one among the possible differential diagnoses that should be considered when dealing with relative diagnostic dilemmas in immature patients.

The potential influence of hormonal imbalance on the development of slipped capital femoral epiphysis was assessed through a prospective clinical study. The serum levels of T3 ,T 4, thyroid-stimulating hormone, testosterone, estradiol, dehydroepiandrosterone-sulfate, follicle-stimulating hormone, luteinizing hormone, human growth hormone, adrenal cortex hormone and cortisol were evaluated in seven boys and seven girls. Forty-three out of 154 hormonal determinations (27.9%) were abnormal. The results showed increased incidence of pathological values mainly in the levels of follicle-stimulating-hormone, luteinizing-hormone and testosterone. No patient had clinical findings of endocrinopathy. A (possibly) temporary hormonal disorder may play a potentially significant role in the development of slipped capital femoral epiphysis.

A case of spontaneous recurrent hemarthrosis--due to developed hypertrophied synovium--after total knee arthroplasty is reported. The patient was successfully treated with radiosynovectomy. The first hemorrhage occurred 18 months after the total knee arthroplasty. Several similar episodes followed over a period of 4 years. Because conservative treatment failed to control the bleeding, an arthroscopic lavage was performed, which revealed the existence of proliferative synovium. A significant part of the hypertrophic tissue was excised with the use of a thermocoagulator. However, 1 month later, another episode of hemarthrosis occurred. As a final step before reoperation, the patient was treated with intra-articular injection of ytrium 90. Eighteen months later, she remains symptom-free, is very satisfied with the result, and reports no new episode of hemarthrosis.

The value of postoperative salvage and re-infusion of drained blood was assessed in 155 patients undergoing total knee arthroplasty for primary knee osteoarthritis. In group A (n = 77), standard vacuum drains were used. In group B (n = 78), an auto-transfusion system was used and the blood drained within 6 hours postoperatively was re-infused. Group B patients were further distributed into 2 subgroups, in one of which methylprednisolone was administered before blood re-perfusion. Patients who received autologous blood had higher levels of haemoglobin at 8 hours (p0.05) and 24 hours postoperatively (p0.01) and needed less allogeneic blood transfusion (p0.01). Methylprednisolone administration was found to attenuate the postoperative febrile reaction (p = 0.01).

A case of painful shoulder in a 42-year old right-hand dominant Caucasian female due to degeneration of the coracoclavicular joint is described. The pain was aggravated by weight lifting. The diagnosis was confirmed radiographically with simple plain films and clinically by the injection of local anaesthetic (xylocaine 2%) that lead to the exclusion of any other concomitant pathology of the acromioclavicular joint and the anterior subacromial space. The patient was treated successfully with an intraarticular steroid injection, and 30 months later she remains free of symptoms.

A multidirectional (anterior and posterior) bilateral habitual nontraumatic dislocation of the hip in a 3-year-old girl with Down syndrome is reported. The treatment was conservative with application of a spica cast for 12 weeks to shrink the capsule. During the first 6 weeks of treatment, the hips were immobilized in abduction and full external rotation. During the last 6 weeks, the hips were in abduction and slight internal rotation. After cast removal, the hips seemed to have been stabilized, and the child has remained asymptomatic for the last 12 months.

[Introduction][1] The FARES (Fast, Reliable, and Safe) method is a new way to reduce acute anterior glenohumeral dislocations that combines the application of gentle longitudinal traction, vertical oscillation movements, and abduction and external rotation of the arm. [Step 1: Position the Patient][2] Place the patient supine on a stretcher, with his/her elbow extended, and advise him/her to hold the stretcher with the opposite hand. ![Figure][3] [Step 2: Brief the Patient][4] Convince the patient that his/her cooperation is necessary for a better outcome. [Step 3: Hold the Arm][5] Holding the patient’s hand with both of your hands, with his/her elbow extended and forearm in neutral rotation, start the procedure at 30° of shoulder abduction. ![Figure][3] ![Figure][3] [Step 4: Apply Traction and Add Oscillations][6] Applying gentle longitudinal traction to keep the arm extended, add gentle vertical oscillating movements. [Step 5: Abduct and Externally Rotate the Arm][7] Gradually abduct the arm to 90° and then gradually externally rotate the arm to achieve full external rotation. ![Figure][3] ![Figure][3] [Step 6: Achieve Reduction][8] The dislocation is usually reduced once 120° to 150° of shoulder abduction has been achieved. ![Figure][3] ![Figure][3] ![Figure][3] [Results][9] In our previously published prospective randomized study, the FARES method was compared with the Hippocratic and the Kocher methods[12][10]. [What to Watch For][11] [Indications][12] [Contraindications][13] [Pitfalls & Challenges][14] [Introduction][1] The FARES (Fast, Reliable, and Safe) method is a new way to reduce acute anterior glenohumeral dislocations that combines the application of gentle longitudinal traction, vertical oscillation movements, and abduction and external rotation of the arm. [Step 1: Position the Patient][2] Place the patient supine on a stretcher, with his/her elbow extended, and advise him/her to hold the stretcher with the opposite hand. ![Figure][3] [Step 2: Brief the Patient][4] Convince the patient that his/her cooperation is necessary for a better outcome. [Step 3: Hold the Arm][5] Holding the patient’s hand with both of your hands, with his/her elbow extended and forearm in neutral rotation, start the procedure at 30° of shoulder abduction. ![Figure][3] ![Figure][3] [Step 4: Apply Traction and Add Oscillations][6] Applying gentle longitudinal traction to keep the arm extended, add gentle vertical oscillating movements. [Step 5: Abduct and Externally Rotate the Arm][7] Gradually abduct the arm to 90° and then gradually externally rotate the arm to achieve full external rotation. ![Figure][3] ![Figure][3] [Step 6: Achieve Reduction][8] The dislocation is usually reduced once 120° to 150° of shoulder abduction has been achieved. ![Figure][3] ![Figure][3] ![Figure][3] [Results][9] In our previously published prospective randomized study, the FARES method was compared with the Hippocratic and the Kocher methods[12][10]. [What to Watch For][11] [Indications][12] [Contraindications][13] [Pitfalls & Challenges][14] [1]: #sec-10 [2]: #sec-11 [3]: pending:yes [4]: #sec-12 [5]: #sec-13 [6]: #sec-14 [7]: #sec-15 [8]: #sec-16 [9]: #sec-17 [10]: #ref-12 [11]: #sec-18 [12]: #sec-19 [13]: #sec-20 [14]: #sec-21