Objective To explore the surgical method and cl inical short-term outcomes of internal fixation combined closed reduction with arthroscope aid in treating patellar fracture. Methods From June 2004 to July 2008, 42 patients with fresh simple patellar fracture underwent internal fixation combined closed reduction with arthroscope aid, included28 males and 14 females, aged 16-59 years (35 years on average). The locations were 19 left knees and 23 right knees. Injury was by traffic accident in 21 cases, by fall ing in 11 cases, by sports in 7 cases and by crush in 3 cases. All the patients had fresh closed fracture, including 38 cases of transverse fracture and 4 cases of stellate fracture. The Lysholm score was 68.60 ± 15.20; the proprioceptive function of the knee joints was (3.72 ± 0.12)°. The time from injury to operation was 3-42 hours (12 hours on average). After the treatment of affil iated injury under the arthroscope, patellar fracture was reduced with manipulation method, fracture was fixed with tensile force screw or modified tension band. Results All incisions obtained heal ing by first intention after operation, 42 patients were followed up for 12-39 months (16 months on average). The X-ray films showed callus at the fracture and the smooth cartilage surface 6-9 weeks (7 weeks on average) after operation. The flexed motion range of knee joint at last follow-up was at normal range in 38 cases, was l imited in 4 cases. Circumference of suffered l imbs 15 cm above the patella was the same as normal ones in 23 cases, atrophied 0.7 cm in 19 cases. There were no breakage of internal fixation and shift of fracture and patellofemoral arthritis at last follow-up. The proprioceptive function of the knee joints was (2.06 ± 0.11)° and the Lysholm score was 95.10 ± 3.92; all showing statistically significant differences when compared with preoperation (P lt; 0.05). Conclusion This treatment method has advantages as follows: mini-wound, early exercises and few compl ications, which can rinse articular cavity and repair the affil iated injury at the same time.
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 evaluate the results of free auto-periosteal graft in primary repair of cartilage defect accompanying severe comminuted fractured of patella. METHODS From January 1992 to August 1998, seventeen cases with extensive cartilage defect due to severe comminuted fracture of patella were primarily repaired with free auto-periosteal graft. In these cases, there were whole patellar fracture in 9 patients, upper two third patellar fracture in 3 patients and lower two third patellar fracture in 5 patients. During operation, "S"-shaped incision along medial side of knee through intra-cavity pathway were used. After fixation of the patellar fracture and clearance of the residual cartilage in the fracture area, the cancellous bone was exposed and trimmed. The free periosteum was incised from the anterior medial side of upper tibia and then transplanted to the region of cartilage defect. The size of grafted periosteum ranged from 3 cm x 4 cm 5 cm 6 x cm. The knee joint was received passive motion at 7 days after operation. RESULTS All cases were followed up 8 to 74 months. There were excellent recovery in 12 patients and the function of knee joint was normal, better recovery in 4 patients and the function of knee joint was nearly normal, and moderate recovery in 1 patient and the function of knee joint was limited mildly. CONCLUSION Free auto-periosteal graft is a simple and effective treatment in primary repair of cartilage defect accompanying patellar fracture. It is valuable to apply in clinical practice.
ObjectiveTo investigate the effectiveness of internal fixation using Kirschner with hole and tension band system with wire winding and pressure in the treatment of patellar fracture. MethodsBetween February 2008 and January 2010, 39 patients with patellar fracture were treated using Kirschner with hole and tension band system with wire winding and pressure. The average age was 37 years (range, 18-65 years), including 23 males and 16 females. The left side was involved in 21 cases and the right side in 18 cases. The causes were falling injury in 21 cases, traffic accident injury in 11 cases, and striking injury in 7 cases. The injury to operation time was 5 hours to 6 days (mean, 3.5 days). Twelve cases had open fractures, and 19 cases had comminuted fractures. ResultsAll incisions healed by first intention, and no deep venous thrombosis of lower limbs formed. Thirty-nine patients followed up 12-21 months (mean, 14 months). There was no wire breaking during operation and after operation. X-ray film showed no re-fracture, fracture displacement, or needle displacement; fracture healed well, fracture line disappeared at 6-8 weeks (mean, 7.5 weeks) after operation. After 12 months, the internal fixation was removed; according to the Lysholm knee score standard, the results were excellent in 22 cases, good in 16 cases, fair in 1 case, and the excellent and good rate was 97.4%. ConclusionInternal fixation using Kirschner with hole and tension band system with wire winding and pressure has satisfactory effectiveness for the treatment of patellar fracture, with the following advantages: wire is not easy to break, the needle does not fall off, and the pressure strength is powerful.
ObjectiveTo estimate the outcome of cerclage followed by a figure-of-eight tension band with a single titanium wire for the treatment of patellar fracture.MethodsA retrospective analysis was made on the clinical data of 46 patients with patellar fractures treated between June 2012 and November 2014. There were 30 males and 16 females, aged 20-86 years (mean, 54 years). The fracture causes included falling in 27 cases, traffic accident in 16 cases, and knock in 3 cases. There were 41 cases of closed fractures and 5 cases of open fracture. The injury located at the left side in 24 cases and the right side in 22 cases. According to AO classification, fracture was rated as type 34-A in 3 cases, as type 34-B in 1 case, as type 34-C1 in 7 cases, as type 34-C2 in 13 cases, and as type 34-C3 in 22 cases. The time between injury and operation ranged 1-12 days (mean, 3.7 days). During operations, a single titanium wire was used to pass around the patellar, followed a figure-of-eight wrapping, to tight and fix at the tension of 35 kg.ResultsAll incisions healed primarily. The patients were followed up 20.6 months on average (range, 6-24 months). Partial wire loosening was found in 2 cases, irritation of skin or soft tissue in 1 case. The X-ray examination showed bony healing at 3 months after operation, without breakage of titanium wire. The internal fixation was removed in 38 cases at 12 months after operation. According to the Böstman rating score, the mean score was 28.34 (range, 24-30) at 12 months after ope-ration; the results were excellent in 42 cases and good in 4 cases, with an excellent and good rate of 100%.ConclusionFor patellar fracture, cerclage followed by a figure-of-eight tension band with a single titanium wire is able to achieve an effective stability and to allow early motion for patient with less complication.
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.
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.
ObjectiveTo compare the biomechanical difference between petal-shaped poly-axial locking plate and tension band wire cerclage in fixing star-shaped 6-part patellar fractures in cadaver model, and provide the experimental data for clinical use.MethodsThe paired 12 knee specimens from 6 human cadavers were randomly divided into 2 groups (the control group and the test group) after a star-shaped 6-part patellar fracture model was established. The specimens were weighted, and the control group was fixed with tension band wire cerclage and the test group was fixed with petal-shaped poly-axial locking plate. The specimens were connected to CMT5105 biomechanics test machine by a customized fixture, the total fracture gap of patellar fracture blocks was measured before testing. The knee extensor load test was performed to record the extensor load of knees at 90° flexion to extension. Then the anti gravity physiological knee extension process at 90° flexion was stimulated according to the knee extensor load. The cyclic times until failure and the total fracture gap of patellar fracture blocks after failure were recorded.ResultsThe specimens weight and the total fracture gap of patellar fracture blocks before testing between 2 groups had no significant difference (t=0.410, P=0.690; t=0.650, P=0.530). In the biomechanical test, there was no significant difference of knee extension load between 2 groups (t=0.490, P=0.638). The total fracture gap after failure in test group was significantly smaller than that in control group (t=3.026, P=0.013), and the cyclic times until failure in test group was significantly more than that in control group (t=2.277, P=0.046). The failure reasons in control group were all the wires slipped off the Kirschner wires, while the failure reasons in test group were the screws pulled out from the upper pole in 5 cases (83.3%) and from the lower pole in 1 case (16.7%).ConclusionThe petal-shaped poly-axial locking plate has better biomechanical stiffness to fix the star-shaped 6-part patellar fractures when compared with tension band wire cerclage method. However, this type of fracture is a serious comminuted type, and the early excessive activity still carries the risk of displacement.
ObjectiveTo explore the effectiveness of high strength suture fixation in treatment of patellar transverse fracture.MethodsBetween June 2014 and June 2016, 38 patients with the patellar transverse fracture were treated with high strength suture internal fixation. There were 24 males and 14 females with the age of 26 to 64 years (mean, 45 years). There were 6 cases of accident injury and 32 cases of crashing injury. The time interval between injury and surgery was 2-8 days (mean, 5 days). The preoperative visual analogue scale (VAS) score, Lysholm score, and range of motion (ROM) of patients were 84.3±8.4, 44.5±7.2, and (62±12)°, respectively.ResultsAll patients’ incisions healed by first intention after operation. There was no neurovascular injury, deep venous thrombosis of lower limbs, or local foreign matter irritation reaction. The X-ray films showed that the reduction of patella and the location of internal fixator were good at 2 days after operation. All the 38 patients were followed up 12-18 months (mean, 16 months). All fractures healed and the healing time was 2-4 months (mean, 3 months). At last follow-up, according to the Böstman criteria, 36 patients were rated as excellent and 2 as good, with an excellent and good rate of 100%. The VAS score, Lysholm score, and ROM of patients were 10.2±6.6, 93.1±6.4, and (124±14)°, respectively, showing significant differences when compared with preoperative ones (t=42.759, P=0.000; t=31.099, P=0.000; t=20.727, P=0.000).ConclusionApplication of high strength suture fixation in the treatment of patellar transverse fracture has advantages of simple to operate, effective fixation, and less complication. It can avoid reoperation of removing the internal fixators. The satisfied ROM and function of the knee joint can be obtained after operation.
ObjectiveTo assess the outcomes in indirect reduction technique via Nice knot for transverse patellar fractures.MethodsThe clinical data of 25 patients with transverse patellar fractures meeting the inclusion criteria between January 2017 and December 2018 were retrospectively analyzed. The patients were divided into trial group (n=13) and control group (n=12) according to different intraoperative reduction methods. No significant difference was found in gender, age, affected side, cause of fracture, classification, or the time from injury to operation between the two groups (P>0.05). In the trial group, No.2 suture was used to cross the quadriceps tendon and patellar tendon to construct the Nice knot, then the suture was tightened to make the distal and proximal fracture segments contact in an indirect reduction pattern. Depend on Nice knot’s sliding compression and self-stabilizing function, the suture mesh created an anterior tension band as a temporary fixation. In the control group, Weber’s clamp was used to hold the fracture segments directly and fixed temporarily. After reduction, terminal fixation was conducted using a titanium Kirschner wire with titanium cable in both groups. The operation time, intraoperative blood loss, follow-up time, fracture healing time, and complications were recorded and compared in the two groups. At last follow-up, the knee function was evaluated according to the Böstman scoring criteria for efficacy in patellar fractures.ResultsThe operation time in the trial group was significantly shorter than that in the control group (t=−2.165, P=0.041). There was no significant difference of intraoperative blood loss between the two groups (t=0.514, P=0.612). The incisions of the two groups healed by first intention. All the patients were followed up 12-16 months, with an average of 14.4 months, no significant difference was found in the follow-up time between the two groups (t=−0.309, P=0.760). One patient in the control group developed soft tissue irritation symptoms at 1 day after operation, and no special treatment was given, the symptoms disappeared at 2 months after operation. The fractures of the two groups healed at the 12-week follow-up. During the follow-up, there was no complication such as loosening and fracture of titanium cables and tendon tissue calcification. At last follow-up, the Böstman score presented no significant difference between the two groups (t=−0.086, P=0.932). In the trial group, an 80-year-old female patient was evaluated as good (score, 27) due to atrophy of the quadriceps femoris, leg weakness, and affected stair climbing, and the rest 24 patients were all evaluated as excellent.ConclusionThe indirect reduction with Nice knot can shorten the operation time in the treatment of transverse patellar fractures, and obtain good effectiveness.