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We aimed to assess the effect of plate hook bending in treatment of acromioclavicular (AC) dislocation by analyzing clinical and radiological results according to the angle of the plate hook (APH). Methods: This was a retrospective, observational, case-control study including 76 patients with acute AC joint dislocation that were divided into two groups according to treatment with bent or unbent plate hook. The visual analog scale (VAS), the American Shoulder and Elbow Surgeons (ASES) shoulder score, and range of motion (ROM) were evaluated as clinical outcomes. Comparative coracoclavicular distance (CCD) was measured to evaluate radiological outcomes. Results: While the VAS and ASES of the bending group at 4 months after surgery were significantly higher (p=0.021 and p=0.019), the VAS and ASES of the bending group at other periods and ROM of the bending group showed no significant difference. The initial CCD decreased from 183.2%±25.4% to 114.3%±18.9% at the final follow-up in the bending group and decreased from 188.2%±34.4% to 119.1%±16.7% in the non-bending group, with no statistical difference (p=0.613). The changes between the initial and post-metal removal CCD were 60.2%±11.2% and 57.3%±10.4%, respectively, with no statistical difference (p=0.241). The non-bending group showed greater subacromial osteolysis (odds ratio, 3.87). Pearson’s coefficients for the correlation between APH and VAS at 4 months after surgery and for that between APH and ASES at 4 months after surgery were 0.74 and –0.63 (p=0.027 and p=0.032), respectively. Conclusions: The APH was associated with improved postoperative pain and clinical outcomes before implant removal and with reduced complications; therefore, plate hook bending is more useful clinically during plate implantation.
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International guidelines recommended screening with ultrasonography (US) every 6 months for patients at risk for hepatocellular carcinoma (HCC). However, US demonstrates low sensitivity for the early detection of HCC. Magnetic resonance imaging (MRI) plays an important role in the noninvasive diagnosis of HCC, but it is not suitable for surveillance due to its lengthy examination and high cost. Therefore, several studies have been using various abbreviated MRI strategies, including noncontrast abbreviated MRI, dynamic contrast-enhanced abbreviated MRI, and abbreviated MRI using hepatobiliary phase image for HCC surveillance. In this article, we aim to review these various strategies and explore the future direction of HCC surveillance considering the cost-effectiveness aspect.
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Background@#The incidence of depression in middle-aged adults is increasing and has been affected by physiological changes and various sociodemographic factors. The present study aimed to examine the longitudinal relationship between depression and changes in the family developmental stage based on child independence in South Korean middle-aged adults living with children. @*Methods@#This study included 1,593 people in the age group of 45-64 years who participated in the first survey of the Korean longitudinal study of aging in 2006. Participants did not have depression, lived with unmarried children, and responded to Center for Epidemiologic Studies Depression 10 scale and child-related questions in the 7th survey (2018). The chi-squared test, t-test, and Mann-Whitney U test were used to compare differences in depression according to general characteristics and family developmental stage. The generalized estimating equation model was used to longitudinally examine the effect of changes in the family developmental stage on the incidence of depression from the 1st to the 7th survey. @*Results@#Changes in the family developmental stage based on child independence have a significant effect on the incidence of depression in middle-aged adults (P=0.000). In addition, in the generalized estimating equation model, the longitudinal association between changes in the family developmental stage and the incidence of depression was confirmed. @*Conclusions@#Therefore, confirming the independence of children as an important factor is essential in the management of depression in middle-aged adults.
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International guidelines recommended screening with ultrasonography (US) every 6 months for patients at risk for hepatocellular carcinoma (HCC). However, US demonstrates low sensitivity for the early detection of HCC. Magnetic resonance imaging (MRI) plays an important role in the noninvasive diagnosis of HCC, but it is not suitable for surveillance due to its lengthy examination and high cost. Therefore, several studies have been using various abbreviated MRI strategies, including noncontrast abbreviated MRI, dynamic contrast-enhanced abbreviated MRI, and abbreviated MRI using hepatobiliary phase image for HCC surveillance. In this article, we aim to review these various strategies and explore the future direction of HCC surveillance considering the cost-effectiveness aspect.
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Background@#Intra-articular distal humeral fractures can be surgically challenging. It remains under discussion whether open reduction internal fixation (ORIF) or total elbow arthroplasty (TEA) is more beneficial for treatment of the elderly. This study aimed to compare the clinical and functional outcomes of ORIF and TEA for managing intra-articular distal humerus fractures in patients aged 65 years or older. @*Methods@#Patients who underwent ORIF (n=28) or TEA (n=43) for in intra-articular distal humerus fracture between May 2008 and December 2018 were reviewed. Range of motion, Mayo Elbow Performance Score (MEPS), Disabilities of the Arm, Shoulder, and Hand (DASH) score, radiologic outcomes, and surgical complications were evaluated at the final follow-up visit. @*Results@#The ORIF and TEA groups showed a mean arc of flexion–extension of 97°±21° and 101°±12°, respectively. The mean MEPS and DASH scores were 94±15 and 27±12 points, respectively, in the ORIF group and 81±27 and 47±28 points in the TEA group. This difference was statistically significant. The incidence of total complications was similar between the groups. @*Conclusions@#In patients older than 65 years with intra-articular distal humerus fracture, ORIF had better outcomes than TEA.
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Lipoma arborescens (LA) is a rare lesion that causes joint effusion and pain. LA usually presents as a unilateral knee lesion, and bilaterallesions are extremely rare. LA among adolescent patients is also extremely rare with the disorder having a much higher incidence amongadults. This paper reports a 14-year-old boy who was treated for bilateral knee LA. X-rays revealed the characteristic features of LA in bothknees, and arthroscopic synovectomy was performed to resect the lesions. Postoperative recovery progressed smoothly, and the patientwas eventually relieved of pain and swelling. LA should be considered when adolescent patients present with bilateral pain and swelling,even though this condition is rare in this age group. Furthermore, surgical synovectomy for a complete resection is an appropriate treatmentoption.
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Purpose@#Spontaneous isolated dissection of the celiac artery (SID-CA) and superior mesenteric artery (SID-SMA) are rare vascular diseases with similar presentation, yet comparative studies have not been reported. In this study, we compared their characteristics with the aim of providing insights into their etiology. @*Materials and Methods@#Patients diagnosed with symptomatic SID-CA and SIDSMA between July 2009 and December 2018 were included. Demographics, clinical presentation, radiologic findings, treatment strategies, and outcomes were analyzed. @*Results@#Twenty-one patients with SID-CA and 40 patients with SID-SMA were compared. Demographics and initial abdominal pain characteristics were similar, but pain severity was significantly higher and associated mean fasting time was significantly longer in patients with SID-CA than in those with SID-SMA (fasting time 3.2 vs 2.1 days, P=0.001). Most patients were successfully treated conservatively without recurrent pain or aneurysmal dilatation, but 33.3% patients with SID-CA and 17.5% with SID-SMA required endovascular intervention. More favorable remodeling in terms of dissection regression on follow-up computed tomography was found after stenting, where patients with SID-CA showed better remodeling than those with SID-SMA. The overall median follow-up period was 22-31 months, while for patients with stent insertion, it was 55-77 months, and no stent occlusions were found during this period. @*Conclusion@#Patients with SID-CA presented with severer and longer-duration abdominal pain than those with SID-SMA. Stenting in both groups showed good long-term patency and favorable remodeling, with a higher regression rate for SIDCA. Based on our results, patients with SID-CA may benefit more from active endovascular intervention.
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Purpose@#Spontaneous isolated dissection of the celiac artery (SID-CA) and superior mesenteric artery (SID-SMA) are rare vascular diseases with similar presentation, yet comparative studies have not been reported. In this study, we compared their characteristics with the aim of providing insights into their etiology. @*Materials and Methods@#Patients diagnosed with symptomatic SID-CA and SIDSMA between July 2009 and December 2018 were included. Demographics, clinical presentation, radiologic findings, treatment strategies, and outcomes were analyzed. @*Results@#Twenty-one patients with SID-CA and 40 patients with SID-SMA were compared. Demographics and initial abdominal pain characteristics were similar, but pain severity was significantly higher and associated mean fasting time was significantly longer in patients with SID-CA than in those with SID-SMA (fasting time 3.2 vs 2.1 days, P=0.001). Most patients were successfully treated conservatively without recurrent pain or aneurysmal dilatation, but 33.3% patients with SID-CA and 17.5% with SID-SMA required endovascular intervention. More favorable remodeling in terms of dissection regression on follow-up computed tomography was found after stenting, where patients with SID-CA showed better remodeling than those with SID-SMA. The overall median follow-up period was 22-31 months, while for patients with stent insertion, it was 55-77 months, and no stent occlusions were found during this period. @*Conclusion@#Patients with SID-CA presented with severer and longer-duration abdominal pain than those with SID-SMA. Stenting in both groups showed good long-term patency and favorable remodeling, with a higher regression rate for SIDCA. Based on our results, patients with SID-CA may benefit more from active endovascular intervention.
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BACKGROUND: In Korea, around the abandoned metal mines, heavy metals are being accumulating in the cultivated areas. Among exposed heavy metals, mercury is known to harm for cardiovascular system known to affect blood pressure. So, we studied the relationship between blood mercury level and hypertension in residents around abandoned metal mines. METHODS: From 2008 to 2011, we surveyed 7,055 residents in provinces affected by abandoned metal mines and collected data from 6 Hospitals. We conducted a personal questionnaire interview survey with residents on the basis of household questionnaires, sex, age, household income, smoking, and drinking items. Multiple logistic regression analysis was performed to investigate the association between blood mercury level and hypertension. RESULTS: We compared residents with low and high groups based on blood mercury level 5.8 μg/L, and higher group was significantly higher risk of hypertension than lower group (odds ratio [OR]: 1.277; 95% confidence interval [CI]: 1.135–1.436), also in adjusted model, higher group was significantly higher risk of hypertension than lower group (OR: 1.276; 95% CI: 1.117–1.457). CONCLUSIONS: This study showed a significant correlation between mercury and hypertension in residents around abandoned metal mines. Therefore, we should continuously monitor people who are higher than the standard value and the hypertensive patients.
Sujets)
Humains , Pression sanguine , Système cardiovasculaire , Consommation de boisson , Caractéristiques familiales , Hypertension artérielle , Corée , Modèles logistiques , Métaux lourds , Fumée , FumerRésumé
Toxocariasis, a parasitic infection, causes hyper eosinophilia resulting in radiological presentation of eosinophilic infiltrations in the involved organs. In the abdomen, toxocariasis has been reported to manifest as infiltrations in the liver or in the gastrointestinal tract, but it is known to be uncommon to manifest as multiple lymphadenopathy. There have been two case reports of toxocariasis presenting as generalized lymphadenopathy in the chest, neck and inguinal regions. To the best of our knowledge, generalized conglomerated lymphadenopathy occurring mostly in the abdomen from toxocariasis has not been published in the English literature. Herein, we report a rare case of toxocariasis presenting as multiple conglomerated lymphadenopathy mimicking lymphoma on CT.
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BACKGROUND: The purpose of this study is to evaluate results of superior labrum anterior to posterior (SLAP) repairs and debridement of type II SLAP lesions combined with Bankart lesions. METHODS: Between 2010 and 2014, total 58 patients with anterior shoulder instability due to a Bankart lesion combined with a type II SLAP lesion were enrolled. Patients were divided into two groups: group C consisted of 30 patients, each with a communicated Bankart and type II SLAP lesion and group NC consisted of 28 patients, each with a non-communicated Bankart and type II SLAP lesion. Bankart repairs were performed for all patients. SLAP lesions were repaired in group C and debrided in group NC. Clinical results were analysed to compare groups C and NC by using the visual analogue scale pain score, American Shoulder and Elbow Surgeons score, Constant scores, Rowe score for instability and range of motion assessments. RESULTS: The clinical scores were improved in both groups at final follow-up. Also, there were no differences between two groups. No significant difference was found in terms of the range of motion measured at the last follow-up. The number of suture anchors used was significantly higher in group C than in group NC (5.6 vs. 3.8; p=0.021). CONCLUSIONS: In this study, it is considered that Bankart repair and SLAP debridement could be a treatment option in patients with a non-communicated type II SLAP lesion combined with a Bankart lesion (study design: IV, therapeutic study, case series).
Sujets)
Humains , Débridement , Coude , Études de suivi , Amplitude articulaire , Épaule , Chirurgiens , Ancres de sutureRésumé
BACKGROUND: In elbow fracture-dislocation, partial excision of the comminuted radial head fracture that is not amenable to fixation remains controversial considering the accompanying symptoms. This study was undertaken to evaluate the results of radial head partial excision when the comminuted radial head fracture involved < 50% of the articular surface in all-arthroscopic repair of elbow fracture-dislocation. METHODS: Patients were divided into two groups based on the condition of the radial head fracture. In Group A, the patients had a radial head comminuted fracture involving < 50% of the articular surface, and underwent arthroscopic partial excision. Group B was the non-excision group comprising patients with stable and non-displacement fractures. Follow-up consultations were conducted at 6 weeks and at 3, 6, 12, and 24 months after surgery. RESULTS: In all, 19 patients (Group A: 11; Group B: 8) met the inclusion criteria and were enrolled in the study. At the final follow-up, all 19 patients showed complete resolution of elbow instability. No significant differences were observed in the range of motion, visual analogue scale score, and Mayo elbow performance score between groups. Radiological findings did not show any complications of the radiocapitellar joint. However, nonunion of the coracoid fracture was observed in 3 patients (Group A: 1; Group B: 2), without any accompanying instability and clinical symptoms. CONCLUSIONS: Considering that the final outcome is coronoid fracture fixation and lateral collateral ligament complex repair for restoring elbow stability, arthroscopic partial excision for radial head comminuted fractures involving < 50% of articular surface is an effective and acceptable treatment for elbow fracture-dislocation.
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Humains , Arthroscopie , Coude , Études de suivi , Ostéosynthèse , Fractures comminutives , Tête , Articulations , Ligament latéral de la cheville , Amplitude articulaire , Orientation vers un spécialisteRésumé
Superior labrum anterior to posterior (SLAP) lesion is a tear of the superior labrum, which starts posteriorly and extends anteriorly to include the anchor of the biceps tendon to the superior labrum. Symptoms of SLAP tear may include pain or instability. Recently, with the development of arthroscopy, the diagnosis and treatment of SLAP lesion have been made a lot. However, the diagnosis of clinically relevant SLAP tears remains challenging because of the lack of specific examination findings and the frequency of concomitant shoulder lesion. And there is still controversy regarding the treatment. Accordingly, proper treatment is important through accurate evaluation of whether or not it is a clinically important SLAP lesion.
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Arthroscopie , Diagnostic , Épaule , Larmes , TendonsRésumé
BACKGROUND: This study was conducted to compare the clinical and radiological outcomes of the locking hook plate fixation (HP) technique and the single tight rope (TR) technique applied for acute high-grade acromioclavicular (AC) joint separations. METHODS: Between 2009 and 2014, 135 consecutive patients with acute AC joint separation Rockwood types III, IV, and V were subjected to surgical reconstruction. One hundred fourteen patients (84.4%) were available for retrospective evaluation. Of them, 62 and 52 were treated using the single TR group and clavicular HP group techniques, respectively. The visual analogue scale, Constant, American Shoulder and Elbow Surgeons (ASES), and Taft scores were used for clinical assessment. Postoperative shoulder range of motion was also assessed. An anteroposterior radiograph of the coracoclavicular distance (CCD) was obtained to evaluate the radiographic signs of recurrence. RESULTS: The TR group patients had better Constant, ASES, and Taft scores than the HP group patients. The loss of reduction in terms of the CCD did not differ between groups. Subacromial osteolysis was observed in 34.6% of the cases in the HP group. However, there were no significant differences in the clinical outcomes between the patients with and without osteolysis in the HP group. Subcoracoid osteolysis, drill tunnel widening, and metal displacement were observed in 3.2%, 22.6%, and 4.8% of the cases in the TR group, respectively. CONCLUSIONS: The single TR technique was relatively more effective at treating acute high-grade AC joint injuries than the HP fixation technique (level of evidence: therapeutic; retrospective comparative study, Level III).
Sujets)
Humains , Articulation acromioclaviculaire , Luxations , Coude , Articulations , Ostéolyse , Amplitude articulaire , Récidive , Études rétrospectives , Épaule , ChirurgiensRésumé
BACKGROUND: To evaluate the clinical and functional outcomes of arthroscopic-assisted reduction and percutaneous screw fixation for glenoid fractures with scapular extension, and investigate the radiologic and clinical benefits from the results. METHODS: We evaluated patients treated with arthroscopic-assisted reduction and percutaneous screw fixation for glenoid fractures with scapular extension from November 2008 to September 2015. Fractures with displacement exceeding one-fourth of the anterior-articular surface or more than one-third of the posterior-articular surface in radiographic images were treated by surgery. Clinical assessment was conducted based on range of motion, Rowe score, and Constant score of injured arm and uninjured arm at last follow-up. RESULTS: Fifteen patients with Ideberg classification grade III, IV, and V glenoid fracture who underwent arthroscopic-assisted reduction using percutaneous screw fixation were retrospectively enrolled. There were no differences in clinical outcomes at final follow-up compared to uninjured arm. Bone union was seen in all cases within five months, and the average time to bone union was 15.2 weeks. Ankylosis in one case was observed as a postoperative complication, but the symptoms improved in response to physical therapy for six months. There was no failure of fixation and neurovascular complication. CONCLUSIONS: We identified acceptable results upon radiological and clinical assessment for the arthroscopic-assisted reduction and percutaneous fixation. For this reason, we believe the method is favorable for the treatment of Ideberg type III, IV, and V glenoid fractures. Restoration of the articular surface is considered to be more important than reduction of fractures reduction of the scapula body.
Sujets)
Humains , Ankylose , Bras , Arthroscopie , Classification , Études de suivi , Ostéosynthèse , Cavité glénoïde , Méthodes , Complications postopératoires , Amplitude articulaire , Études rétrospectives , ScapulaRésumé
BACKGROUND: This study was conducted to compare the clinical and radiological outcomes of the locking hook plate fixation (HP) technique and the single tight rope (TR) technique applied for acute high-grade acromioclavicular (AC) joint separations. METHODS: Between 2009 and 2014, 135 consecutive patients with acute AC joint separation Rockwood types III, IV, and V were subjected to surgical reconstruction. One hundred fourteen patients (84.4%) were available for retrospective evaluation. Of them, 62 and 52 were treated using the single TR group and clavicular HP group techniques, respectively. The visual analogue scale, Constant, American Shoulder and Elbow Surgeons (ASES), and Taft scores were used for clinical assessment. Postoperative shoulder range of motion was also assessed. An anteroposterior radiograph of the coracoclavicular distance (CCD) was obtained to evaluate the radiographic signs of recurrence. RESULTS: The TR group patients had better Constant, ASES, and Taft scores than the HP group patients. The loss of reduction in terms of the CCD did not differ between groups. Subacromial osteolysis was observed in 34.6% of the cases in the HP group. However, there were no significant differences in the clinical outcomes between the patients with and without osteolysis in the HP group. Subcoracoid osteolysis, drill tunnel widening, and metal displacement were observed in 3.2%, 22.6%, and 4.8% of the cases in the TR group, respectively. CONCLUSIONS: The single TR technique was relatively more effective at treating acute high-grade AC joint injuries than the HP fixation technique (level of evidence: therapeutic; retrospective comparative study, Level III).
Sujets)
Humains , Articulation acromioclaviculaire , Luxations , Coude , Articulations , Ostéolyse , Amplitude articulaire , Récidive , Études rétrospectives , Épaule , ChirurgiensRésumé
BACKGROUND: To evaluate the clinical and functional outcomes of arthroscopic-assisted reduction and percutaneous screw fixation for glenoid fractures with scapular extension, and investigate the radiologic and clinical benefits from the results. METHODS: We evaluated patients treated with arthroscopic-assisted reduction and percutaneous screw fixation for glenoid fractures with scapular extension from November 2008 to September 2015. Fractures with displacement exceeding one-fourth of the anterior-articular surface or more than one-third of the posterior-articular surface in radiographic images were treated by surgery. Clinical assessment was conducted based on range of motion, Rowe score, and Constant score of injured arm and uninjured arm at last follow-up. RESULTS: Fifteen patients with Ideberg classification grade III, IV, and V glenoid fracture who underwent arthroscopic-assisted reduction using percutaneous screw fixation were retrospectively enrolled. There were no differences in clinical outcomes at final follow-up compared to uninjured arm. Bone union was seen in all cases within five months, and the average time to bone union was 15.2 weeks. Ankylosis in one case was observed as a postoperative complication, but the symptoms improved in response to physical therapy for six months. There was no failure of fixation and neurovascular complication. CONCLUSIONS: We identified acceptable results upon radiological and clinical assessment for the arthroscopic-assisted reduction and percutaneous fixation. For this reason, we believe the method is favorable for the treatment of Ideberg type III, IV, and V glenoid fractures. Restoration of the articular surface is considered to be more important than reduction of fractures reduction of the scapula body.
Sujets)
Humains , Ankylose , Bras , Arthroscopie , Classification , Études de suivi , Ostéosynthèse , Cavité glénoïde , Méthodes , Complications postopératoires , Amplitude articulaire , Études rétrospectives , ScapulaRésumé
BACKGROUND: This study aimed to evaluate the clinical and radiological outcomes of arthroscopic bioabsorbable screw fixation in osteochondritis dissecans (OCD) in adolescent patients with unstable lesions causing pain. METHODS: The study included 11 patients (10 males and 1 female) with OCD who underwent arthroscopic bioabsorbable screw fixation between July 2007 and February 2014 and were available for follow-up for more than 12 months. The mean age at diagnosis was 16.3 years (range, 11 to 19 years), and the average follow-up period was 51 months (range, 12 to 91 months). Clinical results were evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS), Lysholm knee score, and International Knee Documentation Committee (IKDC) score measured before surgery and at follow-up. Functional evaluation was made using the Tegner activity scale. Magnetic resonance imaging (MRI) and second-look arthroscopy were performed at the 12-month follow-up. RESULTS: Between the preoperative assessment and follow-up, improvements were seen in the KOOS (range, 44.9 to 88.1), Lysholm knee score (range, 32.6 to 82.8), and IKDC score (range, 40.8 to 85.6). The Tegner activity scale also improved from 2.8 to 6.1. Based on postoperative MRI, there were eight Dipaola grade I cases and three grade II cases. No complications due to fixation failure developed in any case. Second-look arthroscopy at 12 months postoperatively revealed that the lesion was covered with cartilage in all cases. CONCLUSIONS: For unstable OCD lesions causing pain in adolescents, arthroscopic bioabsorbable screw fixation provided favorable outcomes with reduced pain and restoration of movement. Therefore, it should be considered as an effective treatment for OCD.
Sujets)
Adolescent , Adulte , Enfant , Femelle , Humains , Mâle , Jeune adulte , Implant résorbable , Arthroscopie/effets indésirables , Vis orthopédiques , Études de suivi , Imagerie par résonance magnétique , Ostéochondrite disséquante/imagerie diagnostique , Amplitude articulaire , Résultat thérapeutiqueRésumé
BACKGROUND: Our aim was to make a comparative analysis of radiological and clinical outcomes of using either one or two interlocking distal screws on a Polarus intramedullary nail for the internal fixation of humeral shaft fractures. METHODS: From January 2008 to March 2014, we enrolled 26 patients with humeral shaft fractures who were operated on using intramedullary nails. The patients were divided into 2 groups according to how many interlocking distal screws were used to lock the Polarus nail: in group 1, a single interlocking distal screw was used in 12 patients; and in group 2, double interlocking distal screws, in 14 patients. We compared the degree of recovery of the displaced fracture fragments between the two groups. To compare the nonunion and shoulder function, we assessed each patient's modified American Shoulder and Elbow Surgerns (ASES) score. RESULTS: We found that 10 of 12 fractures achieved union in group 1, and 13 of 14 fractures, in group 2. We did not find a meaningful difference in the time to bone union between the two groups. The percentage of recovery of displaced fracture fragments until union was 66.9% for group 1 and 59.41% for group 2. At the final follow-up, we found that the scores for shoulder joint modified ASES was 78.7 for group 1 and 80.7 for group 2. CONCLUSIONS: Our results show that if locked appropriately, even a single screw on a Polarus nail can provide satisfactory radiological union and improved clinical outcome after intramedullary nailing of humeral shaft fractures.
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Humains , Vis orthopédiques , Coude , Études de suivi , Ostéosynthese intramedullaire , Fractures de l'humérus , Épaule , Articulation glénohuméraleRésumé
BACKGROUND: Our aim was to make a comparative analysis of radiological and clinical outcomes of using either one or two interlocking distal screws on a Polarus intramedullary nail for the internal fixation of humeral shaft fractures. METHODS: From January 2008 to March 2014, we enrolled 26 patients with humeral shaft fractures who were operated on using intramedullary nails. The patients were divided into 2 groups according to how many interlocking distal screws were used to lock the Polarus nail: in group 1, a single interlocking distal screw was used in 12 patients; and in group 2, double interlocking distal screws, in 14 patients. We compared the degree of recovery of the displaced fracture fragments between the two groups. To compare the nonunion and shoulder function, we assessed each patient's modified American Shoulder and Elbow Surgerns (ASES) score. RESULTS: We found that 10 of 12 fractures achieved union in group 1, and 13 of 14 fractures, in group 2. We did not find a meaningful difference in the time to bone union between the two groups. The percentage of recovery of displaced fracture fragments until union was 66.9% for group 1 and 59.41% for group 2. At the final follow-up, we found that the scores for shoulder joint modified ASES was 78.7 for group 1 and 80.7 for group 2. CONCLUSIONS: Our results show that if locked appropriately, even a single screw on a Polarus nail can provide satisfactory radiological union and improved clinical outcome after intramedullary nailing of humeral shaft fractures.