OBJECTIVE: To measure and compare medial proximal tibial angle (MPTA) of lower limbs under different axial rotation angles(neutral position, 30° internal rotation, 30° external rotation) on the load position radiographs, and explore changes and significance of MPTA measured within and between groups of tibia at different axial rotation positions. METHODS: From January 2018 to December 2018, 40 patients with knee osteoarthritis (KOA) were selected, with a total of 80 limbs, including 12 males and 28 females, aged from 29 to 73 years old with an average of (59.6±12.7) years old. Full length radiographs of the lower limbs were taken on neutral tibia position, 30° internal rotation and 30° external rotation, respectively. MPTA was measured and the results were compared between groups and within groups. RESULTS: MPTA measured on the left lower extremity of neutral tibia, 30° internal rotation and 30° external rotation were (86.08±2.48) °, (88.62±2.94) ° and (83.47±3.10) °, respectively. MPTA measured on the right lower limb were (86.87±1.97) °, (89.02±2.39) ° and (83.80±2.77) °, respectively, and there were no significant difference in MPTA measured between rotation angle group (P>0.05). While there were statistical difference in MPTA on the same limb between groups (P<0.05). On 30° internal rotation, MPTA of left and right lower limbs increased by (2.54±1.74) ° and (2.15±1.78) ° compared with tibia neutral position. On 30° external rotation, MPTA of left and right lower limbs decreased (2.61±2.03) ° and (3.07±1.75) ° compared with tibial neutral position. CONCLUSION When a full-length X-ray film is taken on the weight-bearing position of both lower limbs, if there is axial rotation or external rotation of tibia, MPTA will increase or decrease compared with neutral position, which may cause a certain degree of deviation in clinical operation based on the accurate measurement of MPTA. However, the extent to which this bias affects the clinical operation effect remains to be verified. In addition, limited by the total number of samples and the number of measurement groups, whether there is a linear relationship between MPTA deviation and tibial axial rotation needs to be further studied.
Male ; Female ; Humans ; Adult ; Middle Aged ; Aged ; Tibia/surgery* ; Lower Extremity ; Osteoarthritis, Knee/surgery* ; Radiography ; Osteotomy/methods* ; Knee Joint/surgery* ; Retrospective Studies

PURPOSE: There are no previous epidemiological studies to represent the trends of tibia fractures in the urban setting. The purpose of our study was to provide unique epidemiological information on the incidence of tibia fractures requiring admission in the urban population of Singapore. METHODS: This is a retrospective review of clinical and radiological records encompassing three years period from 2012 to 2014 in a tertiary hospital in Northern Singapore, which covers an adult population of 550,000. Clinical information included demographics, mechanism of injury, and Gustillo-Anderson classification. Radiological records were evaluated by two of the authors and fractures were classified using the AO classification after consensus was reached. RESULTS: There were 214 cases of tibia fractures with a population incidence of 13 in 100,000. Among the tibia fractures, 47% were diaphyseal, 43% proximal and 10% distal. Majority of patients were males with a male to female ratio of 3 to 1. The mean age of females was 64 years while that of males was 40 years. The commonest mechanism of injury was road traffic accident, which contributed to 42% of cases, with motorcyclists making up 78% of all road traffic accidents. Compound fractures made up 23% of all fractures, most of which were Gustillo-Anderson type III; 69% of patients underwent surgical intervention. CONCLUSION The incidence of tibia fractures is 13/100,000 with a male-to-female ratio of 3:1. This incidence is lower than other studies, but the proportion of open fractures were surprisingly high at 23%. Distribution of fractures was unimodal with a peak in younger men and older women. This may signify a component of fragility among tibia fractures, especially proximal and distal fractures, which peaks above the age of 80 years old.
Accidents, Traffic ; statistics & numerical data ; Adult ; Age Factors ; Aged ; Aged, 80 and over ; Female ; Hospitalization ; statistics & numerical data ; Humans ; Incidence ; Inpatients ; statistics & numerical data ; Male ; Middle Aged ; Radiography ; Retrospective Studies ; Sex Factors ; Singapore ; epidemiology ; Tibia ; diagnostic imaging ; Tibial Fractures ; classification ; diagnostic imaging ; epidemiology ; surgery ; Time Factors ; Urban Population ; statistics & numerical data

PURPOSE: To identify the accuracy of postoperative implant alignment in minimally invasive surgery total knee arthroplasty (MIS-TKA), based on the degree of varus deformity. MATERIALS AND METHODS: The research examined 627 cases of MIS-TKA from November 2005 to December 2007. The cases were categorized according to the preoperative degree of varus deformity in the knee joint in order to compare the postoperative alignment of the implant: less than 5degrees varus (Group 1, 351 cases), 5degrees to less than 10degrees varus (Group 2, 189 cases), 10degrees to less than 15degrees varus (Group 3, 59 cases), and 15degrees varus or more (Group 4, 28 cases). RESULTS: On average, the alignment of the tibial implant was 0.2+/-1.4degrees, 0.1+/-1.3degrees, 0.1+/-1.6degrees, and 0.3+/-1.7degrees varus, and the tibiofemoral alignment was 5.2+/-1.9degrees, 4.7+/-1.9degrees, 4.9+/-1.9degrees, and 5.1+/-2.0degrees valgus for Groups 1, 2, 3, and 4, respectively, in the preoperative stage, indicating no difference between the groups (p>0.05). With respect to the accuracy of the tibial implant alignment, 98.1%, 97.6%, 87.5%, and 86.7% of Groups 1, 2, 3, and 4, respectively, had 0+/-3degrees varus angulation, demonstrating a reduced level of accuracy in Groups 3 and 4 (p<0.0001). There was no difference in terms of tibiofemoral alignment, with 83.9%, 82.9%, 85.4%, and 86.7% of each group, respectively, showing 6+/-3degrees valgus angulation (p>0.05). CONCLUSION: Satisfactory component alignment was achieved in minimally invasive surgery in total knee arthroplasty, regardless of the degree of varus deformity.
Aged ; Arthroplasty, Replacement, Knee/*methods ; Bone Anteversion/complications/*radiography ; Bone Malalignment/etiology/*radiography ; Female ; Humans ; Joint Deformities, Acquired/*surgery ; Knee Joint/radiography/*surgery ; Knee Prosthesis ; Male ; Middle Aged ; Minimally Invasive Surgical Procedures/*methods ; Osteoarthritis, Knee/complications/radiography/*surgery ; Postoperative Period ; Preoperative Period ; Range of Motion, Articular ; Tibia/surgery ; Treatment Outcome

BACKGROUNDFor a child with osteosarcoma, prediction of the limb length discrepancy at maturity is important when planning for limb salvage surgery. The purpose of this study was to provide a reliable prediction method.

METHODSA retrospective review of Chinese children receiving chemotherapy for osteosarcoma before skeletal maturity was conducted. Standing full-length radiographs of the lower extremity were used for length measurements. Length-for-age curves were constructed using the LMS method. The lower limb multiplier for a specific age and gender was calculated using the formula M = Lm/L, where M was the gender- and age-specific multiplier, Lmwas the bone length at maturity, and L was the age-specific bone length. Prematurity and postmaturity radiographs were used to assess the accuracy of the prediction methods.

RESULTSA total of 513 radiographs of 131 boys and 314 radiographs of 86 girls were used to calculate the coefficients of the multiplier. The multipliers of 8-, 9-, 10-, 11-, 12-, 13-, 14-, 15-, 16-, 17-, and 18-year-old boys after chemotherapy for osteosarcoma were 1.394, 1.306, 1.231, 1.170, 1.119, 1.071, 1.032, 1.010, 1.004, 1.001, and 1.000, respectively; while for girls at the same ages, the multipliers were 1.311, 1.221, 1.146, 1.092, 1.049, 1.021, 1.006, 1.001, 1.000, 1.000, and 1.000, respectively. Prematurity and postmaturity femoral and tibial lengths of 21 patients were used to assess the prediction accuracy. The mean prediction error was 0 cm, 0.8 cm, and 1.6 cm for the multiplier method using our coefficients, Paley's coefficients, and Anderson's method, respectively.

CONCLUSIONSOur coefficients for the multiplier method are reliable in predicting lower limb length growth of Chinese children with osteosarcoma.

Adolescent ; Body Height ; physiology ; Bone Neoplasms ; surgery ; Child ; Female ; Femur ; anatomy & histology ; Humans ; Limb Salvage ; Lower Extremity ; anatomy & histology ; Male ; Models, Theoretical ; Osteosarcoma ; surgery ; Radiography ; Retrospective Studies ; Tibia ; anatomy & histology

OBJECTIVETo evaluate long-term result of Scorpio posterior-stabilized total knee arthroplasty.

METHODSThere were 160 patients (240 knees) underwent Scorpio posterior-stabilized total knee arthroplasty between December 1998 and December 2000, which were performed by the same surgeon. Patients were followed up from June 2013 to December 2013. Knee Society Scoring (KSS), Hospital for Special Surgery (HSS) patellofemoral scoring, standard weight-bearing anteroposterior and patellar tangential radiographs were assessed. Satisfaction of outcome was requested. Alignment of components and presence of radiolucent lines were assessed by the radiographic scoring system of knee society. Paired t-test was used compared to the data between preoperation and the time of last follow-up.

RESULTSNinety-five patients (141 knees) (59.4%) were followed up. Average follow-up duration was 13.3 years (range 12 to 15 years). Eight knees were revised due to periprosthetic infection (4 knees), aseptic loosening of tibial tray (3 knees) and wear-out of polyethylene insert (1 knee). Compared with preoperative ones, KSS knee score, KSS functional score and range of motion improved significantly (pre-operation: 26±16, 34±18, 87°±25°; follow-up time: 93±8, 78±27, 114°±22°) (t=45.55, 15.60, 13.03, all P<0.01). In terms of KSS knee score and HSS patellofemoral score, 106 knees were rated as excellence respectively. Ninety-five knees had satisfaction with outcome for maximum. The presences of radiolucent lines occurred around 5 femoral and 11 tibial components with range less than 2 mm. The survival rate at 10 years was 94.5% with revision for any reason as the end point.

CONCLUSIONThe long-term study indicates that Scorpio posterior-stabilized knee system shows favorable clinical and radiological results.

Arthroplasty, Replacement, Knee ; methods ; Femur ; diagnostic imaging ; Follow-Up Studies ; Humans ; Knee Joint ; surgery ; Knee Prosthesis ; Patella ; diagnostic imaging ; Polyethylene ; Radiography ; Range of Motion, Articular ; Reoperation ; Tibia ; diagnostic imaging ; Treatment Outcome

BACKGROUND: Distraction osteogenesis (DO) is a promising tool for bone and tissue regeneration. However, prolonged healing time remains a major problem. Various materials including cells, cytokines, and growth factors have been used in an attempt to enhance bone formation. We examined the effect of percutaneous injection of demineralized bone matrix (DBM) during the consolidation phase on bone regeneration after distraction. METHODS: The immature rabbit tibial DO model (20 mm length-gain) was used. Twenty-eight animals received DBM 100 mg percutaneously at the end of distraction. Another 22 animals were left without further procedure (control). Plain radiographs were taken every week. Postmortem bone dual-energy X-ray absorptiometry and micro-computed tomography (micro-CT) studies were performed at the third and sixth weeks of the consolidation period and histological analysis was performed. RESULTS: The regenerate bone mineral density was higher in the DBM group when compared with that in the saline injection control group at the third week postdistraction. Quantitative analysis using micro-CT revealed larger trabecular bone volume, higher trabecular number, and less trabecular separation in the DBM group than in the saline injection control group. Cross-sectional area and cortical thickness at the sixth week postdistraction, assessed using micro-CT, were greater in the regenerates of the DBM group compared with the control group. Histological evaluation revealed higher trabecular bone volume and trabecular number in the regenerate of the DBM group. New bone formation was apparently enhanced, via endochondral ossification, at the site and in the vicinity of the injected DBM. DBM was absorbed slowly, but it remained until the sixth postoperative week after injection. CONCLUSIONS: DBM administration into the distraction gap at the end of the distraction period resulted in a significantly greater regenerate bone area, trabecular number, and cortical thickness in the rabbit tibial DO model. These data suggest that percutaneous DBM administration at the end of the distraction period or in the early consolidation period may stimulate regenerate bone formation and consolidation in a clinical situation with delayed bone healing during DO.
Animals ; Bone Regeneration/*drug effects ; Bone Substitutes/*administration & dosage/*pharmacology ; Disease Models, Animal ; Humans ; Injections ; Male ; Osteogenesis, Distraction/*methods ; Rabbits ; Tibia/radiography/surgery

PURPOSE: Although bilateral lower-limb lengthening has been performed on patients with achondroplasia, the outcomes for the tibia and femur in terms of radiographic parameters, clinical results, and complications have not been compared with each other. We proposed 1) to compare the radiological outcomes of femoral and tibial lengthening and 2) to investigate the differences of complications related to lengthening. MATERIALS AND METHODS: We retrospectively reviewed 28 patients (average age, 14 years 4 months) with achondroplasia who underwent bilateral limb lengthening between 2004 and 2012. All patients first underwent bilateral tibial lengthening, and at 9-48 months (average, 17.8 months) after this procedure, bilateral femoral lengthening was performed. We analyzed the pixel value ratio (PVR) and characteristics of the callus of the lengthened area on serial radiographs. The external fixation index (EFI) and healing index (HI) were computed to compare tibial and femoral lengthening. The complications related to lengthening were assessed. RESULTS: The average gain in length was 8.4 cm for the femur and 9.8 cm for the tibia. The PVR, EFI, and HI of the tibia were significantly better than those of the femur. Fewer complications were found during the lengthening of the tibia than during the lengthening of the femur. CONCLUSION: Tibial lengthening had a significantly lower complication rate and a higher callus formation rate than femoral lengthening. Our findings suggest that bilateral limb lengthening (tibia, followed by femur) remains a reasonable option; however, we should be more cautious when performing femoral lengthening in selected patients.
Achondroplasia/*surgery ; Adolescent ; Bone Lengthening/*methods ; Child ; Child, Preschool ; Female ; Femur/radiography/*surgery ; Humans ; Male ; Retrospective Studies ; Tibia/radiography/*surgery ; Treatment Outcome ; Young Adult

PURPOSE: The purpose of this study was to investigate the correlation between rotational axes of femur and tibia with the use of Linker. MATERIALS AND METHODS: This study was carried out from August 2009 to February 2010 on 54 patients (106 knees), who were diagnosed with simultaneous bilateral total knee arthroplasty. With the use of postoperative computed tomography scans, it was investigated how much the rotational angle of femoral and tibial components matched. RESULTS: The tibial component was internally rotated for the femoral component at an angle of 0.8degrees. The femoral component was externally rotated for the surgical transepicondylar axis (TEA) at an angle of 1.6 (range: from 4.8degrees of internal rotation to 7.9degrees of external rotation, SD=2.2degrees), and the tibial component was externally rotated for the surgical TEA at an average angle of 0.9 (range: from 5.1degrees of internal rotation to 8.3degrees of external rotation, SD=3.1degrees). CONCLUSION: The femoro-tibial synchronizer helped to improve the orientation and positioning of both femoral component and tibial component, and also increase the correlation of the rotational axes of the two components.
Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee/*methods ; Female ; Femur/*radiography/surgery ; Humans ; Knee ; Knee Joint/*radiography/surgery ; Knee Prosthesis ; Male ; Middle Aged ; Reference Values ; Rotation ; Tibia/*radiography/surgery ; Tomography, X-Ray Computed/*methods

PURPOSE: The purpose of this study was to investigate the correlation between rotational axes of femur and tibia with the use of Linker. MATERIALS AND METHODS: This study was carried out from August 2009 to February 2010 on 54 patients (106 knees), who were diagnosed with simultaneous bilateral total knee arthroplasty. With the use of postoperative computed tomography scans, it was investigated how much the rotational angle of femoral and tibial components matched. RESULTS: The tibial component was internally rotated for the femoral component at an angle of 0.8degrees. The femoral component was externally rotated for the surgical transepicondylar axis (TEA) at an angle of 1.6 (range: from 4.8degrees of internal rotation to 7.9degrees of external rotation, SD=2.2degrees), and the tibial component was externally rotated for the surgical TEA at an average angle of 0.9 (range: from 5.1degrees of internal rotation to 8.3degrees of external rotation, SD=3.1degrees). CONCLUSION: The femoro-tibial synchronizer helped to improve the orientation and positioning of both femoral component and tibial component, and also increase the correlation of the rotational axes of the two components.
Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee/*methods ; Female ; Femur/*radiography/surgery ; Humans ; Knee ; Knee Joint/*radiography/surgery ; Knee Prosthesis ; Male ; Middle Aged ; Reference Values ; Rotation ; Tibia/*radiography/surgery ; Tomography, X-Ray Computed/*methods

PURPOSE: The authors have observed a failure to achieve secure fixation in elderly patients when inserting a half-pin at the anteromedial surface of the tibia. The purpose of this study was to compare two methods for inserting a half-pin at tibia diaphysis in elderly patients. MATERIALS AND METHODS: Twenty cadaveric tibias were divided into Group C or V. A half-pin was inserted into the tibias of Group C via the conventional method, from the anteromedial surface to the interosseous border of the tibia diaphysis, and into the tibias of Group V via the vertical method, from the anterior border to the posterior surface at the same level. The maximum insertion torque was measured during the bicortical insertion with a torque driver. The thickness of the cortex was measured by micro-computed tomography. The relationship between the thickness of the cortex engaged and the insertion torque was investigated. RESULTS: The maximum insertion torque and the thickness of the cortex were significantly higher in Group V than Group C. Both groups exhibited a statistically significant linear correlation between torque and thickness by Spearman's rank correlation analysis. CONCLUSION: Half-pins inserted by the vertical method achieved purchase of more cortex than those inserted by the conventional method. Considering that cortical thickness and insertion torque in Group V were significantly greater than those in Group C, we suggest that the vertical method of half-pin insertion may be an alternative to the conventional method in elderly patients.
Aged ; Aged, 80 and over ; *Bone Nails ; Bone Screws ; Diaphyses/radiography/surgery ; *External Fixators ; Female ; Humans ; Male ; Tibia/radiography/*surgery ; *Torque ; X-Ray Microtomography