ObjectiveTo observe the morphological characteristic by implanting domestic porous tantalum in rabbit patellar tendon and to evaluate biocompatibility features so as to provide experimental basis for porous tantalum used as interface fixation between tendon and bone. MethodsA total of 48 adult New Zealand white rabbits, male or female, weighing 2.5-3.0 kg, were selected. Porous tantalum flake (5 mm×5 mm×2 mm) was implanted in the left patellar tendon (experimental group) and the same size porous titanium flake in the right patellar tendon (control group). The animals were sacrificed at 2, 4, 8, and 12 weeks after implantation, then the specimens were harvested for gross observation, HE staining, scanning electron microscope (SEM) observation, and hard slices observation. ResultsNo animal died after operation. Porous tantalum was bonded closely with host tendon and no inflammatory reaction was found. Loose and thick fibrous capsule was observed at the beginning and became density and thinner in the end by microscope, showing significant difference between different time points in 2 groups (P<0.05), but no significant difference was found between 2 groups at different time points (P>0.05). The SEM observation showed that fibrous tissue attached to the surface and inner walls of porous tantalum at early stage, and extended on the material to reach confluence at late period, but the experimental group was more than the control group. Hard slices observation showed that the collagen fibrils were seen on porous tantalum interface with host tendon, and blood vessels grew into the pores. The control group and the experimental group showed no significant difference. ConclusionThe domestic porous tantalum has good biocompatibility. Connection and integration can be established between tendon and porous tantalum, and therefore it could be used in reconstruction of tendon-bone fixation device.
Objective To investigate the effectiveness of transosseous suture in medial patellofemoral ligament (MPFL) double bundle reconstruction. Methods The clinical data of 75 patients with recurrent patella dislocation who met the selection criteria between January 2014 and December 2017 were retrospectively analyzed. All of them were treated with MPFL double bundle reconstruction, and divided into study group (39 cases, using new transosseous suture technique) and control group (36 cases, using traditional suture anchor fixation) depending on the intraoperative fixation technique. There was no significant difference in gender, age, body mass index, affected knee side, preoperative tibial tuberosity-trochlear groove distance, Insall-Salvati ratio, knee range of motion, Kujala score, International Knee Documentation Committee (IKDC) score, congruence angle, and tilt angle between the two groups (P>0.05). The operation time, intraoperative blood loss, hospital stay, and postoperative complications were recorded and compared between the two groups. Kujala score, IKDC score, and knee range of motion were used to evaluate the functional improvement of patients before and after operation. The congruence angle and tilt angle were measured on X-ray films. Results There was no significant difference in operation time, intraoperative blood loss, and hospital stay between the two groups (P>0.05). Patients in both groups were followed up 24-36 months, with an average of 29.4 months. There was no complication such as incision infection, fat liquefaction, patellar redislocation, and prepatellar pain during follow-up. At last follow-up, the Kujala score, IKDC score, knee range of motion, congruence angle, and tilt angle of two groups significantly improved when compared with those before operation (P<0.05), while there was no significant difference between the two groups (P>0.05). ConclusionThe application of suture anchor or transosseous suture to complete MPFL double bundle reconstruction can restore patellar stability, and there is no significant difference in the short-term effectiveness between them.
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.
【Abstract】 Objective To make the young patients with osteoarthritis and genu varum of knee delay total knee arthroplasty,to observe the cl inical effect of mosaicplasty of femoral medial condyle, patellar-plasty and high tibial osteotomy inthe treatment of osteoarthritis of knee with varum. Methods From June 2004 to February 2006, 8 patients with osteoarthritisof knee with varum(10 knees) were treated with combined operation such as mosaicplasty of femoral medial condyle, patellarplastyand high tibial osteotomy. There were 2 males with 3 knees, and 6 females with 7 knees,with an average age of 50 years(42-56 years). The left knees and right knees were involved in 3 cases respectively and bilateral knees in 2 cases. All patients hadknee ache after walk or long-time standing. The X-ray showed hyperosteogeny at peri-patella and circum ferential femur-tibialjoint，especially in the medial. The gap between patella and femur narrowed or disappeared，especially in the medial femurtibialjoint. The femoral tibial angel (FTA) was 185-200°(mean 190°). The HSS score of knee was 55-75(mean 60). The history ofknee ache was 1-12 years(mean 5 years). Results All patients were followed up for 7-24 months (mean 15 months). All theincisions healed by first intention, no early compl ication occurred. The cl inical bone heal ing time was 8-11 weeks(mean 9 weeks).Rectification of FTA was 15-30°(mean 20°). Normal weight-loading al ignment was recovered. The valgus angle of knee was 10°.The range of motion of knee was 100-120° after operation, increasing by 5-20° (mean 10°) when compared with preoperation.The X-ray of postoperation showed that genu varum was corrected obviously and that no displacement, loosening and breakageoccurred. The mean score of HSS was 80 (75-88), increasing by 20 when compared with preoperation. Conclusion Mosaicplastyof femoral medial condyle can make articular cartilage repair in certain degrees, patellar-plasty can rel ieve ache of fore region of knee effectively, and high tibial osteotomy can recover normal weight-loading al ignment. The curative effect is good withthe combined methods.
From 1974 to 1993, 20 patients with dislocation of patella in 26 knees were treated by surgical technique, including 11 males and 9 females, aged from 10 to 67,averaged 31 year old. Thirteen cases (16 knees) were available for followup with an average period of 6.4 years. Using the criteria of Insall, the result were excellent in 5 knees, good in 5 knees, fair in 3 knees and poor in 3 knees with a success rate of 62%. Based on the biomechanism of patella movement and the findings in this study, the mechanism of dislocation of patella and its biomechanical reconstruction principle as well as the factors influencing the operative results were discussed.
ObjectiveTo review research progress of surgical treatment of patellar fractures.MethodsThe domestic and foreign literature about patellar fracture treatment in recent years was extensively consulted, and the advantages, disadvantages, and indications of various surgical treatments were summarized.ResultsThe patella plays an important role in knee flexion and extension activities, and the fracture significantly affects the patient’s quality of life. At present, the surgical methods include open reduction and internal fixation and patella resection. The internal fixation methods include ring/binding patella fixation, tension band wiring and improved technology, tension band wiring combined with other methods, screw fixation (including absorbable screws), steel plate fixation, and patella fixator fixation. Each surgical method has different indications, advantages, and disadvantages. Choosing an appropriate treatment plan plays a crucial role in clinical prognosis.ConclusionThere are many surgical treatments for patellar fractures. In order to improve the effectiveness and reduce postoperative complications, it is necessary to choose the most appropriate treatment strategy for the type of fracture.
Objective To review the progress in the prevention and repair of patellar ligament injury in total knee arthroplasty. Methods Recent literature about the prevention and repair of patellar ligament injury in total knee arthroplasty was reviewed and analyzed. Results Increased exposure can prevent the patellar ligament injury, and treatments of acute patellar ligament rupture can be obtained by simple repair, reconstruction with allograft materials or artificial materials, and auxiliary strengthening. Conclusion Patellar ligament injury in total knee arthroplasty should not be ignored. Active prevention and repair of patellar ligament injury can obtain better function of knee joint.
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.
ObjectiveTo investigate the effectiveness of the arthroscopic lateral retinacular release combined with medial patellofemoral ligament (MPFL) reconstruction for patellar dislocation.MethodsBetween January 2016 and March 2017, 28 cases (32 knees) with patellar dislocation were treated by arthroscopic lateral retinacular release and MPFL reconstruction. There were 6 males (6 knees) and 22 females (26 knees) with an average age of 21 years (range, 17-29 years). The disease duration ranged from 2 days to 2 years (mean, 8 months). Apprehension test of all patients were positive. The preoperative Lysholm score was 68.34±12.26. Anteroposterior X-ray film showed the patellar subluxation or dislocation. The Q angle was (17.67±4.21)° and the distance of tibia tuberosity-trochlear groove was less than 20 mm. The femoral attachment of retinacular were fixed by the interference screws (16 knee) or the anchors (16 knee), respectively.ResultsAll incisions healed by first intention. All patients were followed up 6 months. The function of knee joint was significantly improved at 6 months after operation. The Lysholm score was 92.88±6.42 and the Q angle was (12.15±3.68)° at 6 months. There were significant differences in the Lysholm score and the Q angle between pre- and post-operation (t=–3.408, P=0.006; t=–2.317, P=0.004). Apprehension test of all patients were negative. No knee pain, knee weakness, and patellar dislocation occurred during follow-up. There was no significant difference in the Lysholm score and the Q Angle between the anchor group and interference screw group (t=–3.254, P=0.820; t=–3.576, P=0.940). ConclusionLateral retinacular release combined with MPFL reconstruction under arthroscopy can effectively improve the function of the knee joint for patients with Q angle less than 20° and TT-TG less than 20 mm, and the early effectiveness is good. There is no significant difference in knee function between the anchor and interference screw internal fixation.
Objective To investigate effectiveness of suture anchor fixation combined with Nice knot strapping via longitudinal patellar drilling in the treatment of patellar inferior pole fractures. Methods A clinical data of 37 patients with unilateral patellar inferior pole fracture who met the selection criteria between June 2017 and June 2021 was retrospectively analyzed. Among them, 17 cases were treated with the suture anchor fixation combined with Nice knot strapping via longitudinal patellar drilling (group A), and 20 cases were treated with the traditional Kirschner wire tension band technique (group B). There was no significant difference in terms of gender, age, body mass index, fracture side, combined medical disease, and preoperative hemoglobin between the two groups (P>0.05). Operation time, intraoperative blood loss, postoperative complications, fracture healing time, knee range of motion, and knee function Bostman score (range of motion, pain, daily work, muscle atrophy, walking aids, knee effusion, soft leg, and stair climbing) and grading were recorded in both groups at last follow-up. Results There was no significant difference in operation time and intraoperative blood loss between the two groups (P>0.05). All incisions healed by first intention. All patients were followed up 1-2 years, with an average of 1.7 years. X-ray films reexamination showed that all fractures in group A healed, while 2 cases in group B did not heal. There was no significant difference in bone healing time between the two groups (P>0.05). At last follow-up, the knee range of motion, the range of motion score of Bostman score, total score and effectiveness grading in group A were significantly better than those in group B (P<0.05). There was no significant difference in the other items of Bostman scores between the two groups (P>0.05). During follow-up, 2 cases of internal fixation failure and 1 case of internal fixator irritation occurred in group B, and no complication related to internal fixation occurred in group A. The occurrence of complications was significantly lower in group A than in group B (P<0.05). ConclusionCompared with the traditional Kirschner wire tension band technique, the suture anchor combined with Nice knot strapping via longitudinal patellar drilling for the patellar inferior pole fractures has the advantages of simple operation, reliable fixation, early flexion and extension activity, and better functional recovery of knee joint.