Objective To study the clinical outcome of comminuted factures at distal femur and proximal tibia treated with AO less invasive stabilization systems (LISS). Methods The clinical data of 14 cases of distal femoral fracture and proximal tibial fracture from September 2003 to May 2005 were analyzed retrospectively. The injury was caused by traffic accident in 9 cases, by fall in 3 cases and by slipping in 2 cases. Of 14 cases, there were 5 open fractures and 9 close fractures, including 5 cases of distal femoral comminuted fracture and 9 cases of proximal shaft comminuted fractures. According to AO/OTA classification, the fractures were classified as 33C2 in 3 cases，33C3 in 2 cases,41A2 in 2 cases，41A3 in 2 cases，41B2 in 3 cases and 41C2 in 2 cases. All patients were treated by the internal fixation with LISS-distal femur or with LISS-proximal tibia. Healing of wounds, the X-ray films before and after operations, and therecovery of joint function were observed. Results The patients were followed up from 1 month to 20 months (11 months on average). Twelve cases achieved solid osseous unions from 3 months to 5 months postoperativly; 2 cases had a good reduction and recovered smoothly 2-3 months postoperatively. The results were excellent in 10 cases, good in 3 cases and fair in 1 case according to Johner-Wruhs knee scoring. The range of knee flexion-extension was 110-130° in 11 cases, 100° in 2 cases and 80° in 1 case. Conclusion LISS is an effective method of internal fixation for treating comminntedfracture of distal femur or proximal tibia. It has the advantages of less injury, satisfied reduction and reliable fixation.
Objective To explore an effective way fortreating severe complicated distal femoral fractures. Methods Twenty-six patients with complicated distal femoral fracture who all belonged to 33C3.3type according to AO/ASIF lassification, were treated with a lateral condylar buttress plate or self-desinged aliform anatomical plate, and operated on with allogeneic bone grafting. Results All cases were followed up for an average of 14 months (ranging 5-25 months). Twenty-four wounds were primary healing postoperatively, 2 wounds were infected and healed after dressing change. Twenty-four had bone healing after 411 months, 2 needed to operate again because of earlier weight-bearing resulting in fixation failure. According to shelbourne and Brueckmann score, the excellent and good rate was 88.46%. Conclusion The internal fixation forcomplicated distal femoral fracture by self-designed aliform anatomical plate and lateral condylar buttress plate with a great deal of allograft bone is an effective surgical method. As it has long oval holes and the holes are consecutive ,the aliform anatomical plate is more suitable for severe complicated fractures. At the same time, autogenous-ilium transplantation can be substituted by the allograft bone.
Objective To compare the biomechanical characteristics of the less invasive stabilization system (LISS) and the dynamic condylar screw (DCS) in the fixation of subtrochanteric fractures of the femur so as to provide theoretical basis for choosing internal fixator in clinical application. Methods Twelve cadaveric human femurs (35-50 years old) were selected with similar proximal femur, excluding deformities, fractures, and other lesions. The twelve femur specimens were randomly divided into 2 groups, 6 specimens per group. An 1 cm gap of osteotomy model was made in the proximal femur up to 1 cm below the lesser trochanter to simulate a comminuted subtrochanteric fracture of femur, and the distal end was embedded with denture acrylic and liquid for denture acrylic. Fracture was fixed by LISS in group A, and was fixed by DCS in group B. The specimens were fixed on Instron-8874 servo-hydraulic mechanical testing machine in a single-leg standing position, and the axial compression test and dynamic fatigue test were carried out to compare the compressive strength and the strain distribution at both sides of the fracture line. Results Axial compression test: the strain values of the 2 strain gauges in group A were significantly smaller than those in group B (P lt; 0.01); the vertical down displacement of the femoral head in group A was significantly smaller than that in group B (P lt; 0.01) under the same load; when the load was 600 N, the axial rigidity of group A was (209.06 ± 18.63) N/mm, which was significantly higher than that of group B [(65.79 ± 7.26) N/mm] (t=3.787, P=0.004). Dynamic fatigue test: the vertical down displacement of the femoral head in group A was significantly smaller than that in group B in the same cyclic loading cycle (P lt; 0.01); when the vertical down displacement of the femoral head was 0.5 mm, the force and the cyclic loading cycles in group A were significantly larger than those in group B (P lt; 0.01). Conclusion LISS, which has good mechanical stability, can meet the requirements for subtrochanteric fracture of femur fixation in biomechanics and anatomical structures. It can be proven that the LISS internal fixator is firmer than the DCS internal fixator by biomechanical comparison.
Objective To investigate the development of dynamic hipscrew (DHS) internal fixation in the treatment of intertrochanteric femur fractures. Methods The latest relevant articles were reviewed extensively, including biomechanics and clinical application research. Results DHS is the effective selection for the treatment of intertrochanteric femur fractures, especially by the innovation of DHS structure, operative manipulation.Conclusion Treatment of intertrochanteric femur fractures with DHS is still a gold level, but strict selection of patients, proficiency operation and invasive manipulation are the most essential principles.
ObjectiveTo investigate the effectiveness of rotationplasty in treating osteosarcoma of distal femur in children.MethodsA clinical data of 10 children with osteosarcoma of distal femur treated with rotationplasty between March 2014 and June 2016 was retrospectively analyzed. There were 7 boys and 3 girls with an average age of 6.7 years (range, 4-10 years). There were 4 cases of osteoblastic osteosarcoma, 4 cases of mixed osteosarcoma, and 2 cases of chondroblastic osteosarcoma. All children were staged as Enneking stage ⅡB. The disease duration ranged from 3.5 to 6.0 months (mean, 4.6 months). The lower limb functional scoring system of 1993 Musculoskeletal Tumor Society (MSTS93), Toronto Extremity Salvage Score (TESS), and knee mobility were used to evaluate postoperative function. Tumor recurrence and metastases were monitored by radiograph.ResultsPoor superficial incision healing occurred in 1 patient, and healed after dressing change. The other incisions healed by first intention. All children were followed up 24-72 months (mean, 52.6 months). No local recurrence was observed during follow-up. Three of the ten patients suffered from metastases including 1 dying of multiple organ dysfunction syndrome, 1 alive with tumor, and 1 tumor free survival. Painful callosities and ulcers which related to prosthetic wear occurred in 2 patients and turned up after optimizing prosthetic fit and physiotherapy. The fracture healing time was 2.5-5.0 months (mean, 3.5 months). All children could walk independently at 4 months postoperatively. At last follow-up, the MSTS93 score was 19-25 (mean, 22) and the TESS score was 87-93 (mean, 90). The extension of knee joint mobility with artificial limbs was 0°-10° (mean, 5°), and the flexion of knee joint mobility with artificial limbs was 85°-95° (mean, 90.5°).ConclusionRotationplasty in treating osteosarcoma of distal femur in children with limb salvage difficulties can effectively preserve the limb function and improve the quality of life, and it can be used as an alternative to amputation.
Objective To investigate the effect of the morphological changes in the proximal femur on the prothesis selection in the total hip arthroplasty in the patients with ankylosing spondylitis. Methods The experimental group was composed of 13 patients (16 hips) with ankylosing spondylitis, which was treated with the total hip arthroplasty, and the control group was composed of 16 patients（19 hips）with non-ankylosing spondylitis，which was also treated with the total hip arthroplasty. In the two groups, the measurements of Singh index，canal flare index，morphological index of the cortex and cortical index were performed in the two groups. Results The results of the statistical analysis on Singh index，canal flare index, morphological index of the cortex and cortical index in the experimental group were 3.81±0.54, 2.63±0.41, 2.02±0.38 and 1.69±0.69, respectively, but 4.63±0.62, 3.03±0.27, 2.76±0.28 and 2.12±0.24, respectively in the control group. Therewas a significant difference in Singh index, canal flare index, and morphological index of the cortex between the two groups (Plt;0.05)，while there was no statistical difference in cortical index between the two groups (P＞0.05). The patientswith ankylosing spondylitis had more serious osteoporosis in their proximal femur. Conclusion Cemented femoral prosthesis should be used in the total hip replacement in patients with ankylosing spondylitis, and the revision total hip arthroplasty should be performed on patients with more serious osteoporosis.
Objective To evaluate effectiveness of proximal femur bionic nail (PFBN) in treatment of intertrochanteric fractures in the elderly compared to the proximal femoral nail antirotation (PFNA). Methods A retrospective analysis was made on 48 geriatric patients with intertrochanteric fractures, who met the selection criteria and were admitted between January 2020 and December 2022. Among them, 24 cases were treated with PFBN fixation after fracture reduction (PFBN group), and 24 cases were treated with PFNA fixation (PFNA group). There was no significant difference in baseline data such as age, gender, cause of injury, side and type of fracture, time from injury to operation, and preoperative mobility score, American Society of Anesthesiologists (ASA) score, Alzheimer’s disease degree scoring, self-care ability score, osteoporosis degree (T value), and combined medical diseases between the two groups (P>0.05). The operation time, intraoperative blood loss, number of blood transfusions, transfusion volume, length of hospital stay, occurrence of complications, weight-bearing time after operation, and postoperative visual analogue scale (VAS) score, walking ability score, mobility score, self-care ability score were recorded and compared between the two groups. And the radiographic assessment of fracture reduction quality and postoperative stability, and fracture healing time were recorded. ResultsThe operations in both groups were successfully completed. All patients were followed up 6-15 months with an average time of 9.8 months in PFBN group and 9.6 months in PFNA group. The operation time was significantly longer in PFBN group than in PFNA group (P<0.05), but there was no significant difference in intraoperative blood loss, number of blood transfusions, transfusion volume, length of hospital stay, change in activity ability score, and change in self-care ability score between the two groups (P>0.05). The weight-bearing time after operation was significantly shorter in PFBN group than in PFNA group (P<0.05), and the postoperative VAS score and walking ability score were significantly better in PFBN group than in PFNA group (P<0.05). Radiographic assessment showed no significant difference in fracture reduction scores and postoperative stability scores between the two groups (P>0.05). All fractures healed and there was no significant difference in fracture healing time between the two groups (P>0.05). The incidence of complications was significantly lower in PFBN group (16.7%, 4/24) than in PFNA group (45.8%, 11/24) (P<0.05). ConclusionCompared with PFNA, PFBN in the treatment of elderly intertrochanteric fractures can effectively relieve postoperative pain, shorten bed time, reduce the risk of complications, and facilitate the recovery of patients’ hip joint function and walking ability.
Objective To investigate the morphological changes of the proximalfemur and their implication to the total hip arthroplasty in patients with Crowe Ⅱ/Ⅲ developmental dysplasia of the hip (DDH). Methods The experimental gr oup was composed of 15 hips in 14 patients (Crowe Ⅱ, 9 hips; Crowe Ⅲ, 6 hips ) with osteoarthritis secondary to Crowe Ⅱ/Ⅲ DDH (2 males, 12 females; age, 35-61 years). None of the patients had accepted any osteotomy treatment. The control group was composed of 15 normal hips in 15 patients with unilateral DDH (3 males, 12 females; age, 35-57 years). Twelve hips came from the experimental group and the other 3 came from the patients with unilateral Crowe Ⅰ DDH. The femurswere examined with the CT scanning. The following parameters were measured: theheight of the center of the femoral head (HCFH), the isthmus position (IP), theneckshaft angle(NS), the anteversion angle, the canal flare index, and the canal width. Then, the analysis of the data was conducted. Results HCFH and IP in theexperimental group and the control group were 50.1±6.7 mm, 50.1±7.4 mm, and 107.4±21.5 mm, 108.7±18.1 mm，respectively, which had no significant differencebetween the two groups（Pgt;0.05）. In the experimental group and the control group, the NS were 138.3±10.0° and 126.7±5.7°，the anteversion angles were 36.5±15.9° and 18.8±5.4°, and the canal flare indexes were 4.47±0.40and 5.01±0.43. There was a significant difference between the two groups in the above 3 parameters （Plt;0.05）. As for the canal width of the femur, therewasa significant difference in the interior/exterior widths and the anterior/posterior widths at the level of 2 cm above the lesser trochanter and 4 cm belowthe lesser trochanter between the two groups （Plt;0.05）; however, there was nosignificant difference in the canal width of the femur at the isthmus between the two groups（P＞0.05）. Conclusion It is necessary to evaluate the morphology of the proximal femur before the total hip arthroplasty performed in patients with Crowe Ⅱ/Ⅲ DDH. The straight and smaller femoral prosthesis should be chosen and implanted in the proper anteversion position duringoperation.
Internal fixator is usually adopted in the treatment of bone fractures. In order to achieve anatomical reduction and effective fixation of fractures, the placement of internal fixators should comply with the biology force line of the bone and adapt to the specific anatomical morphological characteristics of the cortical bone. In order to investigate the distribution characteristics and formation regularity of biology force line and cortical thickness of human bone, three-dimensional model of proximal femur is established by using three-dimensional reconstruction technique in this paper. The normal physiological stress distribution of proximal femur is obtained by finite element analysis under three kinds of behavior conditions: one-legged stance, abduction and adduction. The structural topology optimization method is applied to simulate the cortex of the proximal femur under the combined action of three kinds of behavior conditions, and the anatomic morphological characteristics of the proximal femur are compared. The distribution trend of biology force line of proximal femur and the characteristics of cortex are analyzed. The results show that the biology force lines of bone structure and the morphological characteristics of cortex depend on the load of human activities. The distribution trend of biology force line is related to the direction of trabecular bone and the ridge trend and firmness of cortex when bone is loaded physiologically. The proposed analytical method provides a solution to determine the biology force line of bone and the distribution characteristics of cortex. The conclusions obtained may guide the reasonable placement of internal fixator components of fracture.
Objective To evaluate the mid-term effectiveness of cerclage wires fixation in treating Mallory typeⅡperiprosthetic femoral fractures associated with primary hip arthroplasty. Methods A retrospective analysis was made in the data of 14 patients (14 hips) with Mallory typeⅡ periprosthetic femoral fractures associated with primary hip arthroplasty and treated with cerclage wires fixation between January 2010 and June 2011 (fracture group). Twenty-eight patients (28 hips) without periprosthetic femoral fractures associated with primary hip arthroplasty at the same stage were chosen as control group. The uncemented femoral prosthesis were used in 2 groups. There was no significant difference in gender, age, body mass index, and primary disease between 2 groups (P>0.05). The operation time, intraoperative blood loss, and the complications were recorded. The Harris score was used to evaluate the hip function and the visual analogue scale (VAS) score was used to evaluate the pain degree of hip. According to the postoperative X-ray films of hips, Enghet al. standard was used to evaluate the fixed and stable status of the femoral prosthesis; the heterotopic ossification was observed; the time of fracture union was recorded. Results The operation time of fracture group was significantly longer than that of control group (t=–3.590, P=0.001). There was no significant difference in the intraoperative blood loss between 2 groups (t=–1.276, P=0.209). All patients were followed up 64-75 months (mean, 69.5 months). Hip dislocation after operation occurred in 1 case of fracture group; delirium symptom and nonunion of incision occurred in 1 case and 1 case of control group, respectively. There was no significant difference in the Harris score and VAS score at 6 months and 5 years between 2 groups (P>0.05). X-ray films showed that all fractures healed and the mean time of fracture union were 6.1 months (range, 3-12 months). There was no fracture nonunion or malunion evidently. There was no significant difference in X-ray score at 6 months and 5 years between 2 groups (P>0.05). At last follow-up, cerclage wires displacement or breakage did not occur. Heterotopic ossification occurred in 2 cases of fracture group and in 1 case of control group. Conclusion Cerclage wires fixation can achieve the good mid-term effectiveness in treating Mallory typeⅡintraoprative periprosthetic femoral fractures associated with primary hip arthroplasty.