PURPOSE: End-stage knee osteoarthritis (OA) patients are the primary candidates for total knee arthroplasty (TKA). However, most morphological refinements of TKA prosthesis are based on anatomical data from the knees of healthy individuals. This study aimed to determine whether differences exist in key bony morphological characteristics of the distal femur and proximal tibia between osteoarthritic knees and healthy knees. METHODS: This was a retrospective cross-sectional observational study with a case-control design. Patients who were aged ≥ 50 years, had no history of trauma, fracture, or surgery in the studied knee, and had no obvious knee flexion contracture were included in this study by CT scans. Patients who met the American College of Rheumatology clinical criteria for knee OA were included in the study group. Kellgren-Lawrence grade III or IV knees were studied (for bilateral cases, the more severely affected knee was chosen). Patients who presented with unilateral knee pain or trauma were included in the control group, with CT scans from the opposite (asymptomatic) knee used for analyzing. The studied knee had a Kellgren-Lawrence grade of 0 or I and showed no abnormalities upon physical examination. Archived knee CT scans from 160 patients were divided into 2 groups: the study group (80 moderate-to-severe OA knees) and the control group (80 healthy knees). After 3-dimensional reconstruction and virtual cutting using a CT workstation, 13 morphological parameters of the distal femur and proximal tibia were compared between the 2 groups using independent-samples t-tests. RESULTS: No significant group differences in the femoral anteroposterior dimension (p = 0.797), height of the lateral femoral condyle (p = 0.268), posterior condylar angle (p = 0.240), tibial anteroposterior dimension (p = 0.536), or tibial lateral anteroposterior dimension (p = 0.702) were observed. However, the femoral mediolateral dimension (p = 0.002), distal femoral aspect ratio (femoral mediolateral dimension/femoral anteroposterior dimension) (p < 0.001), height of the femoral trochlear groove (p < 0.001), height of the medial femoral condyle (p < 0.001), tibial mediolateral dimension (p = 0.001), proximal tibial aspect ratio (tibial mediolateral dimension/tibial anteroposterior dimension) (p = 0.004), tibial medial anteroposterior dimension (p = 0.005), and tibial asymmetry ratio (tibial medial anteroposterior dimension/tibial lateral anteroposterior dimension) (p = 0.006) were all significantly greater in the study group. CONCLUSION Knees with moderate-to-severe OA are significantly wider than healthy knees, and OA is a risk factor for increased tibial platform asymmetry. When refining the morphological parameters of TKA prostheses, the specific bony morphological characteristics of OA knees should be taken into account to reduce the potential risk of femoral or tibial component underhang and facilitate optimal balance between tibial component fit and rotational alignment.
Humans ; Osteoarthritis, Knee/pathology* ; Male ; Female ; Cross-Sectional Studies ; Retrospective Studies ; Arthroplasty, Replacement, Knee ; Middle Aged ; Aged ; Case-Control Studies ; Prosthesis Design ; Knee Prosthesis ; Femur/anatomy & histology* ; Tibia/anatomy & histology* ; Tomography, X-Ray Computed ; Knee Joint/diagnostic imaging*

OBJECTIVE: To establish a finite element model of the knee joint based on coronal plane alignment of the knee (CPAK) typing method, and analyze the biomechanical characteristics of different types of knee joints. METHODS: The finite element models of the knee joint were established based on CT scan data of 6 healthy volunteers. There were 5 males and 1 female with an average age of 24.2 years (range, 23-25 years). There were 3 left knees and 3 right knees. According to the CPAK typing method, the knees were rated as types Ⅰ to Ⅵ. Under the same material properties, boundary conditions, and axial loading, biomechanical simulations were performed on the finite element model of the knee joint. Based on the Von Mises stress nephogram and displacement nephogram, the peak stresses of the meniscus, femoral cartilage, and tibial cartilage, and the displacement of the meniscus were compared among different types of knee joints. RESULTS: The constructed finite element model of the knee joint was verified to be effective, and the stress and displacement results were consistent with previous literature. Under the axial load of 1 000 N, the stress nephogram showed that the stress distribution of the medial and lateral meniscus and tibial cartilage of CPAK type Ⅲ knee joint was the most uneven. The peak stresses of the lateral meniscus and tibial cartilage were 9.969 6 MPa and 2.602 7 MPa, which were 173% and 165% of the medial side, respectively. The difference of peak stress between the medial and lateral femoral cartilage was the largest in type Ⅳ knee joint, and the medial was 221% of the lateral. The displacement nephogram showed that the displacement of the medial meniscus was greater than that of the lateral meniscus except for types Ⅲ and Ⅵ knee joints. The difference between medial and lateral meniscus displacement of type Ⅲ knee joint was the largest, the lateral was 170% of the medial. CONCLUSION In the same type of joint line obliquity (JLO), the medial and lateral stress distribution of the knee was more uniform in varus and neutral positions than in valgus position. At the same time, the distal vertex of JLO subgroup can help to reduce the uneven medial and lateral stress distribution of varus knee, but increase the uneven distribution of valgus knee.
Humans ; Finite Element Analysis ; Knee Joint/diagnostic imaging* ; Female ; Biomechanical Phenomena ; Adult ; Male ; Young Adult ; Stress, Mechanical ; Weight-Bearing/physiology* ; Computer Simulation ; Tomography, X-Ray Computed/methods* ; Cartilage, Articular/physiology* ; Range of Motion, Articular ; Menisci, Tibial/anatomy & histology* ; Tibia/anatomy & histology* ; Meniscus/diagnostic imaging* ; Femur/diagnostic imaging* ; Models, Biological

OBJECTIVETo compare the difference in the manual measurement of Fengshi (GB 31) between the standing position and the supine position so as to determine the location.

METHODSA total of 197 volunteers were included in the manual measurement of Fengshi (GB 31) at the standing position and 92 volunteers at the supine position. The differences were compared between the two measurements.

RESULTSThe results in the manual measurement at the standing position showed that the distance was (39.27±3.83) cm from the greater trochanter of femur to the popliteal transverse crease [(39.96±4.21) cm in males, (38.82±3.49) cm in females, < 0.05]. The distance was (19.08±2.97) cm from the tip of the middle finger to the popliteal transverse crease [(18.96±3.50) cm in males, (19.16±2.58) cm in females]. After calculating according to the formula of proportional bone measurement, Fengshi (GB 31) was located (9.28±1.44) above the popliteal transverse crease [(9.07±1.64) in males, (9.42±1.29) in females]. The results in the manual measurement at the supine position showed that the distance was (41.89±3.88) cm from the greater trochanter of femur to the popliteal transverse crease [(42.36±3.88) cm in males, (41.67±3.89) cm in females]. The distance was (23.01±3.37) cm from the tip of the middle finger to the popliteal transverse crease [(22.50±3.73) cm in males, (23.25±3.20) cm in females]. After calculated according to the formula of proportional bone measurement, Fengshi (GB 31) was located (10.51±1.69) above the popliteal transverse crease [(10.16±1.75) in males, (10.67±1.63) in females].

CONCLUSIONFengshi (GB 31) is located on the femoral region, in the depression under the tip of the middle finger at the standing position. The simple localization of the acupoint at the supine position: at the supine, the palm touches the middle of the lateral side of the thigh, about 1 directly below the depression under the tip of the middle finger. The location of Fengshi (GB 31) in female is slightly upper than male.

Acupuncture Points ; Female ; Femur ; anatomy & histology ; Humans ; Male ; Meridians ; Posture ; Reference Standards ; Thigh ; anatomy & histology

To investigate the effects of Danshensu on bone formation in ovariectomized rats.Thirty female SD rats were randomly divided into three groups with 10 rats in each:blank control group, model control group and Danshensu group. The osteoporosis model was induced by bilateral ovariectomy and rats in Danshensu group were fed with Danshensu 12.5 mg·kg·dby gavage after ostroporosis model induced. All animals were sacrificed after 90 days. The bone mineral density (BMD) of the whole body, femur and lumbar vertebra was measured by dual energy X-ray absorptiometry. The biomechanical properties of femur were measured by AG-IS mechanical universal testing machine. Serum osteocalcin and bone alkaline phosphates (BALP) levels were measured by ELISA. The number of osteoblasts of proximal femoral metaphysis was counted with light microscopy after HE staining.Compared with blank control group, BMD, biomechanical properties of femur, serum osteocalcin and BALP levels and the number of osteoblasts were decreased in model control group (<0.05 or<0.01). While compared with model control group, BMDs of the whole body, femur and lumbar vertebra, the elastic modulus, maximum load, yield strength, breaking point load of femur, the serum levels of osteocalcin and BALP, and the number of osteoblasts were significantly improved in Danshensu group (<0.05 or<0.01).Danshensu can improve bone quality by increasing bone density, improving biomechanical properties, promoting the expression of osteogenesis-related factors, and increasing the number of osteoblasts.
Alkaline Phosphatase ; blood ; drug effects ; Animals ; Biomechanical Phenomena ; drug effects ; Bone Density ; drug effects ; Cell Count ; Female ; Femur ; anatomy & histology ; cytology ; drug effects ; Lactates ; pharmacology ; Lumbar Vertebrae ; anatomy & histology ; drug effects ; Osteoblasts ; drug effects ; Osteocalcin ; blood ; drug effects ; Osteogenesis ; drug effects ; Osteoporosis ; drug therapy ; Ovariectomy ; Rats ; Rats, Sprague-Dawley

To investigate the effect of icariin total flavonoids capsules (ITFC) on bone mineral density (BMD) and bone histomorphometry in growing rats and its anti-osteoporosis mechanism.Thirty female SD rats were randomly divided into 3 groups:normal control group, ITFC-1 group and ITFC-2 group. Rats in ITFC-1 group and ITFC-2 group were fed with 50 mg·kg·dor 100 mg·kg·dITFC, respectively, and those in normal control group were fed with equal volume of distilled water. The whole body BMD was measured after 4, 8 and 12 weeks, and BMDs of the right femur and lumbar vertebrae were measured after 12 weeks. The serum levels of tartaric acid phosphatase 5b (TRACP 5b) and bone alkaline phosphatase (BALP) were measured by ELISA. Bone morphometry was performed on the right tibia.There were no significant differences in the body weight increase between normal control group and two ITFC groups (all>0.05). There were also no significant differences in whole body BMDs after 4 and 8 weeks between normal control group and ITFC groups (all>0.05). After 12 weeks, the whole body BMD, BMD of bone, serum BALP level and trabecular area in ITFC-1 group and ITFC-2 group were significantly higher, trabecular separation was significantly lower than that in normal control group (all<0.05); and the trabecular width and the number in ITFC-2 group were also significantly higher, and serum TRACP 5b level was significantly lower than that in normal control group (all<0.05). The BMD of bone, serum BALP level, trabecular number and area in ITFC-2 group were significantly higher, and serum TRACP 5b level was significantly lower than that in ITFC-1 group (all<0.05).ITFC can prevent osteoporosis by increasing bone density and bone formation, decreasing bone resorption and improving microstructure of bone.
Alkaline Phosphatase ; blood ; drug effects ; Animals ; Bone Density ; drug effects ; Bone Resorption ; drug therapy ; Cancellous Bone ; anatomy & histology ; Dose-Response Relationship, Drug ; Female ; Femur ; anatomy & histology ; Flavonoids ; pharmacology ; Lumbar Vertebrae ; anatomy & histology ; Osteogenesis ; drug effects ; Osteoporosis ; prevention & control ; Rats ; Rats, Sprague-Dawley ; growth & development ; Tartrate-Resistant Acid Phosphatase ; blood ; drug effects ; Tibia ; anatomy & histology

OBJECTIVETo explore clinical significance of rotational axis of distal femur on Chinese adults in total knee arthroplasty (TKA).

METHODSThere were 86 Chinese adults (106 normal knees) including 47 males (53 knees) and 39 females (53 knees), 54 knees were on left and 52 on right. The CT scan was employed in the distal femur. The scan direction was aligned to be on the plane perpendicular to the mechanical axis of the femoral. The CT images of cross sections across lateral and medial femoral epicondyle were moved to personal computer,lateral angle between anterior posterior line (APL) and surgical transepicondylar axis (STEA) (ATA),lateral angle between posterior condylar line (PCL) and APL (APA), angle between perpendicularity of APL and PCL (A-PA), posterior condylar angle (PCA), condylar twist angle (CTA), angle between clinical transepicondylar axis (CTEA) and STEA (CSA) were measured. These values were divided into different groups according to gender and side, the values of CTA, PCA, A-PA, angle PT (varus of tibia plateau), constant 3, ATA, APA and constant 90° were compared by statistically. A-PA and PCA, and CTA were analysed statistically with the liner regression, the relationship among CTEA, STEA ,PCL, APL and PLP were performed to assess by liner regression.

RESULTSATA was (89.79 ± 1.22)°, APA was (84.84 ± 1.83)°, A-PA was (5.16 ± 1.83)°, PCA was (4.80 ± 1.23)°, CTA was (8.23 ± 1.40), CSA was (3.45 ± 0.68)°. All the parameters had no differences on sex and side,but CSA had difference on male and female. There was no difference among angle PT, PCA, A-PA. There was significant difference in CAT, constant 30 and angle PT, PCA,A-PA. There was no difference between ATA and constant 90°, but there was difference between APA and constant 90°. There was relativity between PCA and CTA, and also PCA and A-PA, CTA and A-PA. There was significant relativity between STEA and CTEA, between STEA and APL, between STEA and PCL, and also between APLP, APL and PCL, but there was no significant relativity between PCL and CTEA.

CONCLUSIONTKA for Chinese, the section of femoral posterior condyle should be external 5° to obtain the optimum rotational orientation. The property is different entirely between STEA and CTEA, the rotational alignment is not performed according to parallel to the CTEA in distal femur. Among STEA, APL, PCL, the STEA is the most reliable mark ofrotational alignment of the distal femur, and the PCL is the less reliable mark.

Adult ; Arthroplasty, Replacement, Knee ; Female ; Femur ; anatomy & histology ; diagnostic imaging ; Humans ; Male ; Middle Aged ; Rotation ; Tomography, X-Ray Computed

BACKGROUND: The purpose of this study was to determine the shape of the distal femur of Korean women compared with the prostheses currently available in Korea. METHODS: Morphometric data (5 parameters) were measured in 356 resected femurs of Korean women undergoing primary total knee arthroplasty (TKA) utilizing the LCS knee implant (DePuy). The data were then compared with 5 additional contemporary TKA implant systems. RESULTS: Implant designs based on Caucasian population data do not ideally match the distal femoral morphology of Korean women. Overhang at the anterior mediolateral width was observed in 84.8% for the LCS while a gender-specific implant resulted in undercoverage of the bone in 86%. Posterior overhang was observed in up to 51.2%. Most implant designs have a narrower intercondylar notch than the morphologic data of Korean women. CONCLUSIONS: Since there is some difference between the shape of distal femur of Korean women and that of the implants, surgeons should have this in mind when selecting an implant for a patient. These data may also be used as a guideline for future prosthetic design options for Korean women population.
Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee/*instrumentation/statistics & numerical data ; Asian Continental Ancestry Group/*statistics & numerical data ; Cohort Studies ; Female ; Femur/*anatomy & histology/*surgery ; Humans ; Knee Joint/surgery ; Middle Aged ; Prosthesis Design ; Republic of Korea

BACKGROUND: Tibial tuberosity-trochlear groove (TT-TG) distance is important in the assessment and treatment of patellofemoral disorders. However, normal and pathological TT-TG values have not been established in Koreans. The purpose of this study was to evaluate the TT-TG distance in the Korean population using lower leg rotational profile computed tomography (CT) scans. METHODS: One hundred rotational profile CT scans were retrospectively collected from patients without knee joint problems aged between 25 to 82 years. TT-TG distances were measured, and statistical analysis was performed. Each CT scan was measured twice in a blinded, randomized manner by three reviewers. Patients with pre-existing knee joint problems were excluded from the study; hence 15 of the 100 patients were excluded because of deformity or unreadable CT scans. Thus, 85 of the 100 patients were included in the study. RESULTS: Interobserver and intraobserver reliability of TT-TG distance measurements was good. The median TT-TG distance for this Korean population was 11.24 mm (mean, 10.24 +/- 0.8 mm). TT-TG distance measured nearly 2 mm less on rotational profile CT scans. CONCLUSIONS: Some of the TT-TG distances on rotational profile CT scans were significantly correlated, indicating that they could be accepted. Furthermore, the values on CT scans showed good reliability. In this study, the TT-TG distance in normal Korean people was approximately 10.24 mm without significant differences in TT-TG values between genders.
Adult ; Aged ; Aged, 80 and over ; Female ; Femur/*anatomy & histology/*diagnostic imaging ; Humans ; Leg/anatomy & histology/diagnostic imaging ; Male ; Middle Aged ; Reference Values ; Republic of Korea ; Tibia/*anatomy & histology/*diagnostic imaging ; Tomography, X-Ray Computed

Objective To explore the feasibility and clinical value of ultrasonography in evaluating the morphology and function of medial collateral ligaments (MCL) after total knee arthroplasty (TKA). Methods Totally 38 patients undergoing routine KTA (group A) and 22 patients undergoing constrained condylar knee arthroplasty KTA with MCL injury (group B) were included. Long axis views of MCL were taken and the MCL thickness was measured on femur side and tibial side 1 cm away from the joint line, respectively. The thicknesses were compared between the two groups. Subsequently, the gap between the metal part of the femoral prosthesis and the spacer after dynamic valgus stress was measured. The distribution and composition of the gap between the two groups were compared. Results High-frequency ultrasound clearly showed the prosthesis and MCL after TKA. MCL fiber structures of both groups were intact. The MCL thickness on the tibial side in group B was (0.25±0.06)cm, which was significantly thinner than group A [(0.32±0.14)cm] (t=2.12, P=0.040).For the femur side, there was no significant difference (t=1.65, P=0.110) between these two groups [(0.37±0.09) cm in group B versus (0.42±0.12)cm in group A]. Under the condition of valgus stress, the gaps between the metal part of the femoral prosthesis and the spacer could be found in 11 cases in group B but only in 1 case in group A. The proportion of gaps in group B was significantly higher than that in group A (Fisher's exact test, P=0.000). Conclusions High-frequency ultrasound can clearly show the prosthesis and MCL after TKA. The injured MCL can be well joined but the thickness is thinner. Under the condition of valgus stress of the knee, the stability of the TKA can be evaluated according to the gap between the prosthesis and the spacer.
Arthroplasty, Replacement, Knee ; Femur ; Humans ; Knee Joint ; Medial Collateral Ligament, Knee ; anatomy & histology ; diagnostic imaging ; physiology ; Tibia ; Ultrasonography

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