Objective To investigate the clinical effect of chitosan in prevention of knee dysfunction due to adhesion after operation for patellar fracture. Methods From March to October 1999, 40 cases of patellar fracturewere treated by internal fixation, with intraarticular injection of 2% chitosan in only 24 cases after fixation and with no chitosan injection in 16 cases(control group). The function of the knee joint, including extension and flexion, was evaluated 1month and 1 year after operation respectively. Results One month after operation, the knees with chitosan injection could actively move in the average range of 104°±23°, and the knees in the control group could move in the average range of72°±16°, which showed significant difference between two groups(P＜0.01); 1 year after operation, the range of movement of the knees with injection was 165°±38° on average, and that of the knees in the control group was 110°± 31°, which also indicated significant difference between two groups (P＜0.05). Conclusion Medical chitosan could effectively prevent or reduce the post-operative adhesion of knee joint after patellar operation.
Objective To introduce a new fluoroscopic method for assessing the quality of medial and lateral joint surface reduction during internal fixation of patellar fractures and to summarize the clinical outcomes of patients treated using this method. Methods A retrospective analysis was conducted on the clinical data of 52 patients with patellar fractures treated between January 2018 and January 2022 who met the inclusion criteria. There were 27 male and 25 female patients, aged 21-75 years, with an average age of 62 years. The types of patellar fractures included 9 transverse fractures, 37 comminuted fractures, and 6 longitudinal fractures. According to the AO/Orthopaedic Trauma Association (AO-OTA)-2018 fracture classification, there were 21 cases of type 34A, 6 cases of type 34B, and 25 cases of type 34C. The time from injury to operation ranged from 1 to 5 days, with an average of 2.3 days. Treatments included internal fixation with hollow screws or hollow screw tension bands, with or without anchor repair. During operation, the medial and lateral joint surfaces of the patella were observed using the tangential fluoroscopic method to assess the smoothness of reduction of the median ridge, lateral joint surface, medial joint surface, and lateral joint edge. Patients were followed up regularly, and X-ray films were taken to observe fracture healing. Knee joint range of motion, Böstman score, and Lysholm score were used to evaluate functional recovery. Results The tangential fluoroscopic method for the medial and lateral joint surfaces of the patella during operation showed satisfactory reduction of the joint surfaces and good positioning of the implants. All patients were followed up 12-16 months, with an average of 13.4 months. During the follow-up, fracture displacement occurred in 1 case and titanium cable breakage in 1 case. All patella fractures healed successfully, with a healing time of 8-16 weeks (mean, 11.4 weeks). At last follow-up, knee joint range of motion ranged from 120° to 140°, with an average of 136°. The Böstman score ranged from 20 to 30, with an average of 28, yielding excellent results in 45 cases and good results in 7 cases. The Lysholm score ranged from 88 to 100, with an average of 93, yielding excellent results in 40 cases and good results in 12 cases. Conclusion The intraoperative application of the tangential fluoroscopic method for the medial and lateral joint surfaces of the patella can quickly determine the fluoroscopic plane of the patella, accurately assess the quality of fracture reduction and the position of internal fixator, thereby improving effectiveness.
Objective To establish the finite element model of Y-shaped patellar fracture fixed with titanium-alloy petal-shaped poly-axial locking plate and to implement the finite element mechanical analysis. Methods The three-dimensional model was created by software Mimics 19.0, Rhino 5.0, and 3-Matic 11.0. The finite element analysis was implemented by ANSYS Workbench 16.0 to calculate the Von-Mises stress and displacement. Before calculated, the upper and lower poles of the patella were constrained. The 2.0, 3.5, and 4.4 MPa compressive stresses were applied to the 1/3 patellofemoral joint surface of the lower, middle, and upper part of the patella respectively, and to simulated the force upon patella when knee flexion of 20, 45, and 90°. Results The number of nodes and elements of the finite element model obtained was 456 839 and 245 449, respectively. The max value of Von-Mises stress of all the three conditions simulated was 151.48 MPa under condition simulating the knee flexion of 90°, which was lower than the yield strength value of the titanium-alloy and patella. The max total displacement value was 0.092 8 mm under condition simulating knee flexion of 45°, which was acceptable according to clinical criterion. The stress concentrated around the non-vertical fracture line and near the area where the screws were sparse. Conclusion The titanium-alloy petal-shaped poly-axial locking plate have enough biomechanical stiffness to fix the Y-shaped patellar fracture, but the result need to be proved in future.
目的:探讨陈旧性髌骨骨折的最佳治疗方案。方法:我院1997.1～2007.12收治陈旧性髌骨骨折患者20例,均采用术前髌骨牵引、股四头肌锻炼,术中髌前纵形S切口、改良张力带固定骨折块,配合关节腔注射玻璃酸钠,术后早期行患肢CPM机功能锻炼。结果: 所有患者均获得随访,随访时间1.5～3.5年,平均2.2年。患者术后X片髌骨骨折块对位良好、关节面平整。术后切口甲级愈合,下床时间2d～21d,平均6.5d。骨折愈合时间3.0～6.5月,平均4.2月。术后1.5年膝关节HSS功能评分:优8例,良8例,可3例,差1例,优良率80%。结论: 术前牵引、术中正确处理骨折、术后术后早期锻炼等综合治疗陈旧性髌骨骨折疗效显著。
Objective To analyze the reasons for internal fixation failure after internal fixation of nickel-titanium memory alloy patella claw for patella fracture, and to explore the countermeasures. Methods The clinical data of patients with patellar fracture treated by internal fixation of nickel-titanium memory alloy patella claw in the Second Orthopedic Ward of Chongqing Orthopedic Hospital of Traditional Chinese Medicine from May 2015 to April 2020 were analyzed retrospectively. Patients with postoperative internal fixation failure were identified. The reasons for internal fixation failure were analyzed. Results A total of 436 patients were included. Internal fixation failure occurred in 10 patients. There were 6 cases (1.38%) of patellar claw detachment, and 4 cases of simple fracture block displacement witharticular surface displacement≥2 mm (0.92%). Internal fixation failure occurred 4 to 48 days postoperatively, with an average of (18.20±10.86)days. The analysis showed that the reason for internal fixation failure in 4 patients was improper early postoperative functional exercise. The reason for 3 patients was that the auxiliary internal fixation was not selected. The reason for 2 patients was that the size of the patellar claw was too small. The reason for 1 patient was the improper fixation of the auxiliary internal fixation. Conclusion The failure of internal fixation after patella fracture with nickel-titanium memory alloy patella claw is mainly related to whether the model of the patella claw is appropriate, whether the auxiliary internal fixation is selected, whether the auxiliary internal fixation is properly fixed, and whether the early postoperative functional exercise is appropriate.
From August 1986 to October 1990, 34 cases of fractures of patella were treated by the self-designed spring Kirschner wire, in which, 25 cases were followed up for an average of 1.5 years. The excellentgood rate reached 88%. In comparing with the traditional method of treatment, it gave more secure fixation for fracture, without the need or only a short time of immobilization needed, short treatment course and satisfactory return of function.
Objective To investigate the effectiveness of three-dimensional strapping reduction in treatment of patellar fracture. Methods Between January 2015 and June 2015, thirty-two patients were randomly allocated to three-dimensional strapping reduction group (trial group) and towel clamp reduction group (control group). There was no significant difference in age, gender, damage side, interval from injury to opreration, fracture pattern, and cause of injury (P>0.05). The operation time, fluoroscopy time, fracture healing time, postoperative Hospital for Special Surgery (HSS) scores, and complications were collected and analysed. Results All incisions healed at stage I. All patients of 2 groups were followed up 10-14 months (mean, 12.4 months). The operation time and fluoroscopy time of trial group were both shorter than those of control group (t=6.212, P=0.000; t=6.585, P=0.000). X-ray films showed that the fractures in both groups healed successfully and there was no significant difference in healing time between groups (t=1.973, P=0.058). Bone nonunion, infection, and failure fixation were not found in both groups. HSS scores of trial group (91.6±3.8) was higher than that of control group (86.4±5.5) (t=–3.105, P=0.004). Conclusion Compared with towel clamp reduction, the three-dimensional strapping reduction in treatment of patellar fracture has the advantages of shorter operation time and fluoroscopy time, better knee function after operation, and satisfactory fracture healing.