OBJECTIVES:This study aims to evaluate the reliability of cervical vertebral maturation (CVM) staging in determining skeletal maturity in patients with adolescent idiopathic scoliosis (AIS), focusing on the effect of professional experience among orthopedic surgeons. PATIENTS AND METHODS:Between January 2023 and January 2025, this reliability and agreement study included a total of 72 patients aged between nine and 16 years who were diagnosed with AIS. Intra- and inter-rater reliability were analyzed using weighted kappa (κ) statistics with standard errors (SEs) and 95% confidence intervals (CIs). A total of 72 full-spine lateral radiographs were independently assessed by 10 raters with varying levels of orthopedic expertise, including medical students, residents, consultants, and spinal surgeons. None of the raters had prior experience with the CVM classification. Each rater performed CVM staging twice with a four-week interval between assessments. RESULTS:Of the patients, 33 were male and 39 were female with a mean age of 13.07 ± 1.97 (range, 9 to 16) years. Overall intra-rater reliability was substantial (κ = 0.64, SE = 0.032, 95% CI: 0.569-0.714), and overall inter-rater reliability was moderate (κ = 0.52). Although spinal surgeons showed slightly higher intra-rater reliability overall, inter-rater reliability declined between assessments (first assessment κ = 0.61 vs. second assessment κ = 0.34). Consultants exhibited the highest inter-rater agreement (κ = 0.62), whereas residents showed improvement between assessments (κ = 0.40 vs. 0.52); however, no significant difference observed between groups. CONCLUSION:The reliability of CVM staging for assessing skeletal maturity in AIS patients does not significantly differ across levels of orthopedic expertise. While CVM staging has potential as a radiation-sparing method, the overall moderate agreement, particularly among physicians without prior experience, indicates that reliability is not significantly influenced by professional experience.

Objectives This study aimed to investigate the interobserver reliability of a hybrid templating method for total knee arthroplasty, utilizing conventional acetate templates in conjunction with calibrated digital radiographs displayed on a computer screen. Methods Two orthopedic surgeons independently performed templating to estimate implant sizes for 30 knees in 26 patients. Standardized digital anteroposterior (AP) and lateral knee radiographs were obtained for each patient, with a custom copper rod positioned at the level of the knee joint to facilitate calibration. Digital radiographs were calibrated for magnification using a ruler on the computer screen. Templating was then conducted by overlaying acetate templates onto the digital images. Results For the first observer, 60% (36/60) of the estimations matched the actual implant sizes used. This increased to 98.3% (59/60) when considering estimations within one size of the actual components. For the second observer, 61.7% (37/60) of the estimations were exact matches, and 100% (60/60) were within one size of the actual components. The interclass correlation coefficient (ICC) was 0.92 (95% confidence interval [CI]: 0.87–0.95). Conclusion The hybrid templating method for total knee arthroplasty, employing conventional acetate templates over digital radiographs, demonstrates high interobserver reliability and may provide a cost-effective alternative for orthopedic surgeons lacking access to dedicated digital templating software.

OBJECTIVE:This study aimed (1) to simulate pedicle screw pullout after intraoperative external wall perforation and (2) to assess restoration strength with different thread designs in the pedicle screw instrumentation for osteoporotic thoracic vertebrae.METHODS:Twenty fresh-frozen human cadaveric thoracic vertebra bodies were prepared and divided into 4 groups: group 1, 5.5 mm × 45 mm polyaxial single thread pedicle screws (PASTS); group 2, after wall injury 5.5 mm × 45 mm PASTS; group 3, 6.5 mm × 45 mm PASTS after wall injury; and group 4: 6.5 mm × 45 mm polyaxial mixed-threaded screws after wall injury. While group 1 was the control group, groups 2, 3, and 4 were used as study groups after the lateral wall breach. All prepared screw units were placed on a universal pullout measurement testing device.RESULTS:The mean bone mineral density for 20 thoracic vertebrae was 0.57 ± 0.12 g/cm2 (range 0.53-0.6 g/cm2 ). The mean pullout strength was 474.90 Newtons (N) for group 1, 412.85 N for group 2, 475.4 N for group 3, and 630.74N for group 4. The lateral wall breach caused a 14.1 % decrease in average pullout strength compared with the initial screw pullout. Mixed (double)-threaded screws increased pullout strength compared to 6.5 mm screws (P=.036) Conclusion: Using a 1 mm thicker polyaxial pedicle screw or mixed (double)-threaded pedicle screw seems to increase pullout strength; however, this was statistically significant only for group 4. In the thoracic spine, the redirection possibility of the pedicle screw is limited, and augmentation with cement will not be appropriate due to the risk of wall injury-related leakage. Therefore, care should be taken to avoid violating the lateral cortex by using appropriate pedicle entry points and trajectories.

AIM: To investigate the importance of thoracic kyphosis (TK) for treatment preference in patients with Lenke Type 5C adolescent idiopathic scoliosis by comparing radiological outcomes of the patients who underwent selective fusion (SF) or nonselective fusion (NSF). MATERIAL and METHODS: Twenty-nine patients with Lenke Type 5C AIS were included and then divided into two groups as per the fusion procedure used in the surgical treatment. SF group including 16 patients (14 female patients; mean age = 15.56 yr; age range, 14-18) with normal TK and NSF group including 13 patients (nine female patients; mean age = 15.54 yr, age range, 13-18) with thoracic hyperkyphosis. Thoracolumbar/lumbar (TL/L) Cobb, thoracic (T) Cobb, TK and lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS) were measured on standing spine radiographs preoperatively and at the final follow-up. The correction rates (CRs) of Cobb angles and the difference in each other radiological parameters were calculated. RESULTS: No significant differences were observed in the mean CRs of TL/L Cobb and T Cobb angles, PI, SS, and PT (p=0.313, p=0.444, p=0.51, p=0.472, and p=0.14, respectively). However, significant differences were observed in the mean TK angle, which was -2.13 degrees +/- 13.52 degrees (range, 29-27 degrees) in SF group and 28.46 degrees +/- 15.05 degrees (range, -4 degrees-degrees 47 degrees) in NSF group (p=0.001), and LL angle was 0.88 degrees +/- 14.23 degrees (range, -21 degrees-32 degrees) in SF group and 11.54 degrees +/- 17.79 degrees (range, -31 degrees-34 degrees) in NSF group (p = 0.016). CONCLUSION: In patients in whom Lenke's sagittal modifier is N, SF can be performed efficiently. NSF can be preferred for those with (+) Lenke's sagittal modifiers as it provides better TK control.

Objectives: Greulich-Pyle (GP) is one of the most used method for bone age determination (BAD) in various orthopedic, pediatric, radiological, and forensic situations. We aimed to investigate the inter- and intra-observer reliability of the GP method between the most relevant disciplines and its applicability to the Turkish population.Methods: One-hundred and eighty (90 boys, 90 girls) patients with a chronological age younger than 18 (mean 9.33) were included. X-rays mixed by the blinded investigator were evaluated by two orthopedists, two radiologists, and two pediatric endocrinologists to determine skeletal age according to the GP atlas. A month later the process was repeated. As a statistical method, Paired t-test was used for comparison, an Intraclass Correlation Coefficients test was used for reliability and a 95 % confidence interval was determined. Results were classified according to Landis-Koch.Results: All results were consistent with chronological age (p<0.001), according to the investigators' evaluations compared with chronological age. At the initial evaluation, the interobserver reliability of the method was 0.999 (excellent); at the second evaluation, the interobserver reliability was 0.997 (excellent). The intra-observer reliability of the method was 'excellent' in all observers. When results were separately evaluated by gender, excellent intraobserver correlation and excellent correlation with chronological age were found among all researchers (>0.9). When X-rays were divided into three groups based on age ranges and evaluated, 'moderate' and 'good' correlations with chronological age were obtained during the peripubertal period.Conclusions: The GP method used in skeletal age determination has excellent inter- and intra-observer reliability. During the peripubertal period, potential discrepancies in bone age assessments should be kept in mind. This method can be used safely and reproducibly by the relevant specialists.

To the Editor: I read with great interest the publication by Hsieh et al, ‘The role of counter-torque holders in tightening of pedicle screw-rod constructs: a biomechanical study in a porcine model’ [ [1] Hsieh MK Liu PY Li YD et al. The role of counter-torque holders in tightening of pedicle screw-rod constructs: a biomechanical study in a porcine model. Spine J. 2023; 23: 315-324 Abstract Full Text Full Text PDF Scopus (1) Google Scholar ]. The authors conducted this biomechanical study to investigate the strain changes in the pedicles during tulip-set screw tightening and the role of counter-torque. They used 12 L4 to L5 fresh-frozen implanted porcine lumbar vertebrae and measured the strain changes of each pedicles’ inner and outer cortex by strain gauges during tightening. Finally, they found that in all testing groups the maximal strain values were significantly higher when a counter-torque holder was not used concluded that using a counter-torque is necessary during tulip-set screw tightening.

We read with great interest the publication by Vigdorchik et al., ‘High Prevalence of Spino-pelvic Risk Factors in Patients with Postoperative Hip Dislocations’ [ [1] Vigdorchik J.M. Madurawe C.S. Dennis D.A. Pierrepont J.W. Jones T. Huddleston 3rd, J.I. High prevalence of spinopelvic risk Factors in patients with post-operative hip dislocations. J Arthroplasty. 2022; Google Scholar ]. The authors conducted this case-control study in 48 patients who had one or more postoperative dislocations after primary hip arthroplasty. They measured pelvic tilt (PT) and lumbar flexion (LF) in standing and flexed-seated lateral x-rays and pelvic incidence, supine PT, pelvic incidence, and acetabular cup orientation in computed tomography scans. They calculated ‘adverse pelvic mobility’ of the cohort and the prevalence of ‘at risk’ spino-pelvic parameters according to literature thresholds, and finally compared the results to a previously published cohort of 9,414 total hip arthroplasty (THA) patients. They concluded that excessive standing posterior PT, low LF, and a severe sagittal spinal deformity, are more prevalent in unstable THAs.

Objective: This study aimed to investigate biomechanically the effects of onlay fibula grafts on Vancouver Type B1 Periprosthetic Femoral Fractures (PPFs). Methods: Vancouver Type B1 PFF models were created in 25 fourth-generation synthetic femurs and fixed with locking plates using bicortical, unicortical screws, and cables. While no graft was used in group 1, onlay fibula grafts were placed anteriorly in group 2 and medially in group 3. In group 4, the cortical strut allograft was placed on the medial femoral cortex, and a locking compression plate (LCP) was applied to the lateral femoral cortex. In group 5, the strut allograft was placed over the anterior cortex of the femur and fixed with the same technique as in group 4. All models were then subjected to rotational and axial cyclical stiffness tests and load to failure to measure and compare the mechanical strengths of the constructs. Results: The mean stiffness values of group 4 with medial allograft, before and after cyclical loading, were higher than all other groups, under both rotational and axial forces. The mean stiffness values of fibula autografts (groups 2 and 3) were similar to that of anterior allografts (group 5) in each test except that the mean initial axial stiffness of group 5 was higher than group 2. Failure loads were also not different between the groups. Conclusion: Although the rigidity of Vancouver type B1 periprosthetic femur fractures is highest if allografts are placed medially, fibula autografts can also provide similar fixation strengths to allografts if locking plates with unicortical and bicortical screws and cables are used.

BACKGROUND It's well known fact that Hallux valgus (HV) alternates foot biomechanics. In different populations HV and postural stability has been studied but HV and adolescent ballet dancer has not been studied. Aim of the our study is to explore affect of HV on adolescent ballet dancers' balance. Also we wanted to explore health related quality of life of adolescent ballet dancers with HV. METHODS Ballets aged between 8-16 years old has been screened prospectively. The dancers divided into two groups group 1;Ballets with HV and group 2; Ballets without HV. HV diagnosis was made clinically. Two groups were compared according to balance parameters and health related quality of life (HRQOL) questionaires. RESULTS Group 1 was formed with 31 participants and group 2 was formed with 24 participants. All participants in both groups were female. Mean age in group 1 was 11.6 (8-16 years old) and 12.2 (8-16 years old) in group 2. Mean first metatarsophalangeal angle was 13.4° (10°-15°) in group 2 and 19.8° (16°-25°) in HV group respectively. A statistically significant difference was found according to the nonparametric Mann Whitney U test results in the comparison of HVA (Hallux Valgus Angle) between groups. According to Spearman Rho correlation analysis, it was determined that the increase in HVA caused deterioration in the static Flamingo test. (r=0.552 p=0.019). No significant relationship was found between HRQoL questionaries and the presence of HV. (p>0,05) Conclusions: Adolescent ballet dancers experience static balance impairment due to HV angle increase. Clinical measurement of HV and application of balance parameters made easy without need of set ups to perform evaluation with high numbers of participants in concordance with literature.

Objective:Patients with a C6 radiculopathy-mimicking complaint are always in the gray zone if the diagnosis is not clear. The aim of the study is to make the diagnosis clear if the neck and shoulder pain is caused by a dynamic stenosis of the neural foramen at the C5-C6 level. Methods:Patients with a C6 radiculopathy-mimicking complaint were included in the study. Patients had a cervical spine magnetic resonance imaging (MRI) at the normal limits, or a minimal protrusion at the C5-C6 level underwent a dynamic MRI procedure. We measured the foraminal area and spinal cord diameter (SCD) at the C5-C6 level by using the PACS system ROI irregular are determination integral embedded to PACS. Inter- and intraobserver reliability of measurements was evaluated. Results were analyzed statistically, and a p value< 0.05 was accepted as statistically meaningful. Results:A total of 23 patients between January 2019 and June 2019 were included in the study. There were 10 men and 13 women, and the mean age was 41.3 (range 33-53). Foraminal area decrease at C5-C6 in extension and increase in flexion when compared with the neutral position was statistically significant (p < 0.001). Foraminal area changes between the complaint side and the opposite side was not statistically different (p > 0.05). Interobserver and intraobserver reliability of measurements were classified as in almost perfect agreement. Conclusions:Our present work presented dynamic and positional foraminal changes in MRI with radiculopathy-mimicking patients. Soever, we did not find a difference between the clinical complaint side and the opposite side in radiculopathy-mimicking patients. Cervical radiculopathy pain should not be attributed only to foraminal sizes. PACS embedded irregular area measurement integral allows the easy measure of a big number of patients without additional set-up and digital work requirements.

Objectives Plate osteosynthesis is the most commonly used surgical method in the treatment of diaphyseal forearm fractures in adults. Intramedullary nailing (IMN) is an easy surgical alternative for treating these fractures. In the present study we discussed the minimum 2 year follow up results of intramedullary nailing for the management of forearm fractures in a secondary trauma center. Methods A retrospective analysis of patients operated for adult forearm fractures, using intramedullary locking nails, between 2013 and 2015 in a secondary trauma center was performed. Patient demographics and clinical characteristics were retrieved from the hospital database. The union rates and complications were also recorded. Results Twenty nine patients (22 M 7 F) with mean age 29.4 years (range: 19 and 51) were included into the study. Mean follow up time was 26.8 months (range: 24 and 36). Twenty one patients had fracture of both bones, 4 had isolated ulna and 4 had isolated radius fractures. There were 2 open fractures. Average clinical healing time was approximately 20 days and radiologic healing time was 40 days. One patient with an open fracture underwent revision with plate screw fixation due to union delay. Patients improved in terms of health related quality of life questionnaire scores. Conclusion The intramedullary locking nail is a suitable treatment method for the surgical treatment of forearm fractures, and can be an alternative to open reduction and internal fixation with plate screw constructs when the patients can not undergo open surgery due to different factors.

BACKGROUND:Biphalangealism has been evaluated in many studies and has been shown as a common variant. Its frequency varies according to the populations. This epidemiological study aimed to determine the prevalence of biphalangealism for each toe in the Turkish population and compare it with other populations.METHODS:The local hospital radiological database was searched for all consecutive foot radiographs, obtained between 2014 and 2018. Anteroposterior (AP) and oblique radiographs obtained to evaluate trauma or foot pathologies were included. Two-phalangeal toes according to radiographical views were defined as biphalangeal and other three-phalangeal toes were defined as normal.RESULTS:A total of 2,881 radiographs of 2,710 adult patients met the incusion criteria. There were 1,558 (57.5%) female and 1,152 (42.5%) male patients. The cases were unilateral in 2,539 patients and bilateral in 171 patients. The overall prevalence of biphalangeal third toe was 0.29%, fourth toe was 1.29%, and fifth toe was 23.3%.CONCLUSIONS:The presence of pedal biphalangealism is a common variant and its frequency varies according to the populations. The exact cause is still unclear. Further studies are required to assess the clinical impact of biphalangealism.

BackgroundAlthough Lenke classification analyses the sagittal plane as (+), N, and (-), it does not consider it in the choice of treatment, and it has limitations with overall thoracic kyphosis (TK). To investigate the importance of TK for treatment preference in patients with Lenke 5C adolescent idiopathic scoliosis (AIS) by comparing radiological outcomes of the patients who underwent selective fusion (SF) or nonselective fusion (NSF). MethodsThirty-two patients with Lenke type 5C AIS were included and then divided into two groups as per the fusion procedure used in the surgical treatment. SF group including 17 patients (15 females; mean age = 16 years, age range, 14–21) with normal TK and NSF group including 15 patients (11 females; mean age = 17 years, age range, 13–26) with thoracic hyper-kyphosis. Thorocolumbar/lumbar (TL/L) Cobb, thoracic (T) Cobb, TK and lumbar lordosis (LL) were measured on standing spine radiographs preoperatively and at the final follow-up. The correction rates (CR) of each radiographic parameter were calculated.ResultsNo significant differences were observed in the mean CR of all radiographic parameters, except TK and LL correction rates. The mean CR of TK was significantly higher in NSF group (-17% [range, -100–69]) than in SF group (67% [range, 9–100]) (p = 0.000). Likewise, the mean CR of LL was found significantly higher in NSF group (12.47% [range, -100–51]) than in SF group (-2.41% [range, -75–47]) (p = 0.036).ConclusionIn patients in whom Lenke's sagittal modifier is N, SF can be performed efficiently. NSF should be preferred in those with Lenke's sagittal modifiers (+) as TK can be better controlled with NSF.Level of Evidence: 3

Objective:The current reported rate of revision after surgery for adult spinal deformities (ASDs) is up to 45%.The aim of this study was to analyze patients with ASD who underwent failed primary surgery and required revision surgeries, in order to identify the reasons for failure and revision, while assessing possible prognostic criteria.Materials and Methods: Thirty-two patients (27 women, 5 men) with a mean age of 69.8 years and follow-up period of 44.6 months were included.Before first revision, patients had a mean sagittal vertical axis (SVA) of 94.2 mm, lumbar lordosis (LL) of 33.3°, thoracic kyphosis (TK) of 35.3°, pelvic incidence (PI) of 56.9°, pelvic tilt (PT) of 27.8°, PI-LL of 24.9°, and coronal Cobb angle of 22°.Mean duration from the initial surgery until the first revision was 34.8 months.Fusion levels extended from T1 to S2.Twenty patients received transforaminal lumbar interbody fusion and 9 received anterior lumbar interbody fusion cages.Five patients underwent corpectomy combined with anterior cage.Three patients underwent ponte-, and 7 underwent pedicle subtraction osteotomies.Results: After the last revision surgery, patients' sagittal plane parameters were significantly corrected (p<0.001 for mean SVA, LL, PT, PI-LL mismatch and coronal Cobb).The most frequent reason for revision was found as advanced sagittal malalignment (ASM) in 29 patients (90.6%) followed by proximal junctional kyphosis (PJK) in 13 patients (40.6%).The most common surgical planning mistakes leading to revision were detected as proximal short fusion extending to thoracolumbar junction and not to T10, thus avoiding the stabilizing effect of the rib cage in 18 patients (56.3%); followed by no bone cement [polymethylmethacrylate (PMMA)] augmented screw application despite documented osteoporosis in 17 patients (53.1%). Conclusion:The present study concluded that ASM and PJK were the most common reasons for revision following ASD surgery, while short proximal level of instrumentation and not placing PMMA augmented pedicle screws in patients with documented osteoporosis were the most common surgical planning pitfalls leading to revision.

Address for Correspondence/Yazışma Adresi: Serdar Beken, M.D., Acıbadem University Faculty of Medicine, Department of Pediatrics, Neonatology Subdivision, İstanbul, Turkey Phone : +90 532 671 31 96 E-mail : serbeken@gmail.com ORCID: orcid.org/0000-0002-8609-2684 Received/Geliş tarihi: September 1, 2020 Accepted/Kabul tarihi: October 13, 2020 ©Copyright 2021 by Turkish Society of Hematology Turkish Journal of Hematology, Published by Galenos Publishing House Turk J Hematol 2021;38:222-223 DOI: 10.4274/tjh.galenos.2020.2020.0530 Beken S. et al: Intrauterine Arterial Ischemia

The pullout strength of the pedicle screws after direct vertebral rotation (DVR) maneuver is not known. This biomechanical study was performed to quantitatively analyze the pullout strength of a pedicle screw after DVR maneuver using human cadaveric vertebrae. Thoracic vertebral bodies from three cadavers were harvested and stripped of soft tissues. Thirty pedicles of 15 vertebrae were separated into two groups after bone mineral density measurements. Polyaxial 5.5 mm pedicle screws with appropriate length were inserted with a freehand technique for each pedicle. One Kirschner wire was inserted to the anterior part of each vertebral corpus the half depth of each corpus was embedded into PVC pipes using polyester paste. In the DVR group, each screw was pulled horizontally with 2 kg (~20 N) load over a screwdriver rigidly attached to the screw, and a DVR maneuver was simulated. The control group did not load with a DVR maneuver. Samples were placed on a universal testing machine and pullout loads were measured. The Mann-Whitney U test was utilized, and the P value <0.05 was considered as statistically significant. In the DVR group, the mean pullout strength was 183.35 N (SD ± 100.12), and in the control group, the mean pullout strength was 279.95 N (SD ± 76.26). Intergroup comparisons revealed that DVR maneuver significantly decreases the pullout strength (P = 0.012). The results of this study confirm that the pullout strength of pedicle screw significantly decreases by approximately 35% when DVR maneuver is applied.

Introduction: Proximal junctional kyphosis - PJK has been defined by a 10 or greater increase in kyphosis at the proximal junction as measured by the Cobb angle from the caudal endplate of the uppermost instrumented vertebrae (UIV) to the cephalad endplate of the vertebrae 1 segments cranial to the UIV. In this biomechanical study, it is aimed to evaluate effects of interspinosus ligament complex distruption and facet joint degeneration on PJK development. Materials and methods: Posterior instrumentation applied between T2 - T7 vertebrae using pedicle screws to randomly selected 21 sheeps, divided into 3 groups. First group selected as control group (CG), of which posterior soft tissue and facet joints are protected. In second group (spinosus group, SG) interspinosus ligament complex which 1 segment cranial to UIV has been transected, and third group (faset group-FG) was applied facet joint excision. 25 N, 50 N, 100 N, 150 N and 200 N forces applied at frequency of 5 Hertz as 100 cycles axial to the samples. Then, 250 N, 275 N and 300 N forces applied static axially. Interspinosus distance, kyphosis angle and discus heights was measured in radiological evaluation. Abnormal PJK was defined by a proximal junctional angle greater than 100 and at least 100 greater than the corresponding preoperative measurement. Results: In CG group, average interspinosus distancewas 6,6 +/- 1.54 mm and kyphosis angle was 2,2 +/- 0.46 degrees before biomechanical testing, and they were measured as 9,4 +/- 1.21 mm and 3,3 +/- 0.44 degrees respectively after forces applied to samples. In SG group, average interspinosus distance was 6,2 +/- 1.72 mm and kyphosis angle was 2,7 +/- 1.01 degrees before experiment, and they were measured as 20,8 +/- 5.66 mm and 15,1 +/- 2.34 degrees respectively after forces applied to samples. In FG group, average interspinosus distancewas 4,8 +/- 1.15 mm and kyphosis angle was -1 +/- 4.14 degrees before experiment, and they were measured as 11,1 +/- 1:96 mm and 11 +/- 2.87 degrees respectively after forces applied to samples. In comparison to group CG, statistically significant junctional kyphosis was seen on both FG and SG group after statistical analysis. (p < 0.05). PJK was seen statistically significant more on SG group than FG group. (p < 0.05). Not any statistically significant difference was seen on measurement of disk distances among three groups. (p > 0.05) Conclusions: Protecting interspinosus ligament complex and facet joint unity during posterior surgical treatment for spine deformation is vital to prevent PJK development. Based on our literature review, this is the first biomechanical study that reveals interspinosus ligament complex are more effective on preventing PJK development than facet joints. (C) 2019 Turkish Association of Orthopaedics and Traumatology. Publishing services by Elsevier B.V.

ObjectiveTotal knee replacement (TKR) is a surgical treatment for final stage gonarthrosis. The lifespan of the prosthetic implants used in TKR surgery is a major interest for the orthopaedic research community.Previously, proper implant alignment of the implants has been advocated for longevity of the TKR surgery. Recently, patient-specific (PSI) instruments have been proposed to improve the mechanical alignment of the TKR by permitting better implant positioning over conventional TKR surgery. The aim of this study is to compare the mechanical alignment results of patients operated with PSIs and conventional instruments.MethodsTwo groups of 20 patients chosen in a quasi-random manner have been compared in this study. In the first group femoral distal and tibial osteotomies were made by a PSI which was produced by the patients' computed tomography scans. All osteotomies in the control group were made with the TKR set's routine instruments by conventional means. Patients' preoperative and postoperative mechanical femorotibal angles (mFTA), femoral coronal angles (FCA), tibial coronal angles (TCA) were measured and the number of outliers which showed more than 3° of malalignment were counted in both groups for comparison.ResultsThe average postoperative mFTA was found to be 2.09° for the PSI group and in was found to be 2.84° for the control which was not statistically significant. The comparison of postoperative FCA and TCA also did not show significant difference between the groups. The number of outliers showing more than 3° of malalignment per group were found to be 1 out of 20 (5%) for the PSI group and 7 out of 20 (35%) for the control which was statistically significant.ConclusionIn this study patient-specific instrumentation provided significantly better mechanical alignment compared to conventional TKR for the frequency of outlier cases with malalignment beyond 3°. PSI proved no significant difference when the groups were compared for mFTA, FCA and TCA. Our findings support that PSI may improve TKR alignment by improving the ratio of the outlier patients with marked malalignment.Level of EvidenceLevel III, Therapeutic Study.

We report the outcomes of mechanical prophylaxis and chemoprophylaxis in patients who underwent elective surgery for idiopathic adolescent scoliosis (AIS). We retrospectively studied the patients who underwent posterior spinal instrumentation for AIS. The patients were divided into three groups: Group A low-molecular-weight heparin (LMWH) started at 8 hours after surgery; Group B LMWH started at 24 hr after surgery; Group C did not receive chemoprophylaxis. The data about wound oozing, need for transfusion, preoperative and postoperative hemoglobin level, length of stay in hospital, interval from the surgery to removal of closed suction drainage tube, postoperative blood loss from closed suction drain, deep venous thrombosis (DVT), and pulmonary embolism (PE) were investigated. The mean age and Lenke classification for all the groups were similar. No DVT or PE was detected in any group. The mean blood loss from the drain was higher in Group A (400 mL) and Group B (450 mL) when compared to Group C (150 mL) (P=.001). There were more wound oozing in Groups A (5) and B (6) than in Group C (3) (P=.585). Three patients in Group B, 3 patients in Group A, and no patient in Group C had superficial infections. However, there was no statistical difference between the groups (P=.182). Postoperative hospital stay was significantly longer in Groups A (6 days) and B (6 days) then in Group C (5 days) (P=.001). Our current study claims that chemoprophylaxis is not necessary for the patients without risk factors after AIS surgery. Early mobilization and mechanoprophylaxis represents adequate prophylaxis in addition to pain management and well hydration in patients' routine treatment. The complications of chemoprophylaxis are not correlated to the initiation time of prophylaxis.

The aim of this study is to compare the effects of high versus low implant density on correction in Lenke type 5 adolescent idiopathic scoliosis (AIS) patients. A retrospective study of 59 Lenke type 5 AIS patients treated at a single institution were divided into to 2 groups according to implant density. Implant density, preoperative, early postoperative, and last follow-up thoracolumbar/lumbar (TL/L) curves were measured. Thirty-one constructs were high and 28 constructs were low density. The groups were similar in terms of age, sex, Cobb angle, and follow-up time. Mean implant density in low density group and high density group was 75.4% and 96.6%, respectively. High versus low-density comparison showed that there is no significant difference with regard to curve correction in early postoperative and last follow-up periods. The results show that pedicle screw density being low or high, does not affect curve correction rates in the short and long term in our patients.