Plating of patella fractures: techniques and outcomes

Anterior variable-angle locked plating of complex patella fractures - Does the type of polar screw matter?

BACKGROUND

Treatment of complex patella fractures represents a challenging clinical problem. Whereas controversy exists regarding the most appropriate fixation method, anterior plating is an emerging treatment option. A novel design of anterior variable-angle locking plates features radiating legs with integrated screw holes aiming at capturing fragments of the distal comminuted zone via either a locking or a cortical polar screw. The aim of this study was to compare the biomechanical performance of the novel anterior variable-angle locking plates used for fixation of complex patella fractures with either a locking or a cortical polar screw.

METHODS

Complex five-part AO/OTA 34-C3 patella fractures mimicking comminution around the distal pole were simulated in twelve human cadaveric knees. Specimens were randomized to two groups for treatment with an anterior variable-angle locking plate fixing the patella with either one locking or one cortical caudo-cranial bicortical polar screw. Biomechanical testing was performed over 5000 cycles by pulling on the quadriceps tendon, simulating active knee extension and passive flexion within the range from 90° flexion to full extension. Interfragmentary movements were captured by motion tracking.

FINDINGS

No significant differences between the two fixation techniques were detected in terms of longitudinal and shear articular displacements, and relative rotations around the mediolateral axis measured between the proximal and distal fragments at the central patella aspect between 1000 and 5000 cycles, P ≥ 0.116.

INTERPRETATION

From a biomechanical perspective, anterior locked plating of complex patella fractures provides comparable fixation stability when using either a locking or a cortical polar screw.

Clinical and functional outcomes of locked plating vs. cerclage compression wiring for AO type C patellar fractures- a retrospective single-center cohort study

PURPOSE

Although "tension-band wiring" is still commonly used to stabilize patellar fractures, the technique has recently been scrutinized due to biomechanical insufficiency. Consequently, the AO Foundation renamed the principle to compression cerclage wiring (CCW). Several studies propose favorable outcomes when utilizing locked plating (LP). This study aims to compare outcome of CCW and LP for complex patellar fractures.

METHODS

A retrospective, single-center cohort study was performed on patients who underwent operative treatment for (AO 34 C-Type) patellar fractures between April 2013 and March 2023. Patients with a 12 month follow up were included. We grouped and compared patients based on the applied treatment strategy: group LP vs. group CCW. Primary outcome parameters included implant-related complications and revision surgeries. Secondary outcomes were length of stay, return to work and 12 months functional outcome (Lysholm score). Odd ratios for complications and revisions were calculated using the conditional Maximum Likelihood Estimate. The threshold for statistical significance was set at p < 0.05.

RESULTS

Of 145 patients, 63 could be included (group LP: n = 23 and group CCW: n = 40). Fractures in group LP were significantly more complex in regard to AO Classification (p < 0.001), number of fragments (p < 0.001) and degree of comminution (p < 0.001), yet odds of complications were significantly lower in group LP (OR: 0.147; 95%CI: 0.015-0.742; p = 0.009). K-wire migration was the most common complication in group CCW (20%). Odds of revision surgery were significantly lower in group LP (OR: 0.000; 95%CI: 0.000-1.120; p = 0.041). The average Lysholm score at one year was favorable in both groups (89.8; SD: 11.9 in group LP and 90.6; SD: 9.3 in group CCW; n.s.).

CONCLUSION

In our study cohort, LP was routinely chosen for more complex fracture morphologies; nevertheless the data implies that LP may be considered as the superior fixation technique in regard to complications and revision operations. Especially, K-wire migration occurs frequently after CCW. The one year functional outcome was comparable between the groups, with both demonstrating good results. Prospective randomized studies are indicated to validate our findings.

CT of Periarticular Adult Knee Fractures: Classification and Management Implications

Periarticular knee fractures, which include fractures of the distal femur, tibial plateau, and patella, account for 5%-10% of musculoskeletal injuries encountered in trauma centers and emergency rooms. These injuries are frequently complex, with articular surface involvement. Surgical principles center on reconstruction of the articular surface as well as restoration of limb length, alignment, and rotation to reestablish functional knee biomechanics. Fixation principles are guided by fracture morphology, and thus, CT with multiplanar reformats and volume rendering is routinely used to help plan surgical intervention. Fractures involving the distal femur, tibial plateau, and patella have distinct management considerations. This comprehensive CT primer of periarticular knee fractures promotes succinct and clinically relevant reporting as well as optimized communication with orthopedic trauma surgeon colleagues by tying fracture type and key CT findings with surgical decision making. Fracture patterns are presented within commonly employed fracture classification systems, rooted in specific biomechanical principles. Fracture typing of distal femur fractures and patellar fractures is performed using Arbeitsgemeinschaft für Osteosynthesefragen/Orthopedic Trauma Association (AO/OTA) classification schemes. Tibial plateau fractures are graded using the Schatzker system, informed by a newer explicitly CT-based three-column concept. For each anatomic region, the fracture pattern helps determine the surgical access required, whether bone grafting is warranted, and the choice of hardware that achieves suitable functional outcomes while minimizing the risk of articular collapse and accelerated osteoarthritis. Emphasis is also placed on recognizing bony avulsive patterns that suggest ligament injury to help guide stress testing in the early acute period. ©RSNA, 2024 Supplemental material is available for this article.

Lateral rim variable angle locked plating versus tension band wiring of simple and complex patella fractures: a biomechanical study

INTRODUCTION

Treatment of both simple and complex patella fractures is a challenging clinical problem. Although tension band wiring has been the standard of care, it can be associated with high complication rates. The aim of this study was to investigate the biomechanical performance of recently developed lateral rim variable angle locking plates versus tension band wiring used for fixation of simple and complex patella fractures.

MATERIALS AND METHODS

Sixteen pairs of human anatomical knees were used to simulate either two-part transverse simple AO/OTA 34-C1 or five-part complex AO/OTA 34-C3 patella fractures by means of osteotomies, with each fracture model created in eight pairs. The complex fracture pattern was characterized by a medial and a lateral proximal fragment, together with an inferomedial, an inferolateral, and an inferior (central distal) fragment mimicking comminution around the distal patellar pole. The specimens with simple fractures were pairwise assigned for fixation with either tension band wiring through two parallel cannulated screws or a lateral rim variable angle locking plate. The knees with complex fractures were pairwise treated with either tension band wiring through two parallel cannulated screws plus circumferential cerclage wiring or a lateral rim variable angle locking plate. Each specimen was tested over 5000 cycles by pulling on the quadriceps tendon, simulating active knee extension and passive knee flexion within the range of 90° flexion to full extension. Interfragmentary movements were captured via motion tracking.

RESULTS

For both fracture types, the articular displacements measured between the proximal and distal fragments at the central patella aspect between 1000 and 5000 cycles, together with the relative rotations of these fragments around the mediolateral axis were all significantly smaller following the lateral rim variable angle locked plating compared with tension band wiring, p ≤ 0.01.

CONCLUSIONS

From a biomechanical perspective, lateral rim variable angle locked plating of both simple and complex patella fractures provides superior construct stability versus tension band wiring under dynamic loading.

A study of fracture lines distribution characteristics in complete articular fractures of the patella

Objective

The objective of this study was to unveil the characteristics of fracture lines distribution and explore its clinical significance of complete articular fractures of the patella.

Methods

A consecutive series of image data from 88 patients with complete articular patella fractures were retrospectively included. Three-dimensional reconstruction images of the patella fractures were created and collected. Subsequently, these reconstructed images were visually overlaid onto a standard anterior and posterior patella template. The fracture lines were then identified, traced onto the template, and utilized to generate patella fracture maps. Furthermore, the incidence rate of patella fracture lines involving the distal pole was analyzed.

Results

The maps depict the fracture lines of complete articular patella fractures. For simple and complex patella fractures, the primary fracture lines primarily converge within the Middle and Lower regions, exhibiting a transverse pattern. Conversely, the primary fracture lines in comminuted patella fractures are randomly dispersed across the patella. Examining the maps, approximately 63.6% (56/88) of complete articular patella fractures exhibited involvement of the distal pole in the anterior view, while 48.9% (43/88) displayed distal pole fractures in the posterior view. The incidence of distal pole injury increased progressively with the severity of patella fractures.

Conclusion

The patterns and distribution of fracture lines in cases of complete articular patella fractures are prominently illustrated on the constructed fracture maps. Familiarity with these common characteristics of complete articular patella fracture, especially with the distal pole injury, can aid surgeons in developing preoperative planning, executing surgical strategies effectively, and reducing inappropriate treatment.

A novel technique of a new cannulated screw for treatment of inferior pole patellar fractures: a finite element study

OBJECTIVE

We invented a new cannulated screw with holes on the tail, which called Ding's screw. The goal of this study was to evaluate the biomechanical outcomes of this new screw with tension band wiring for the treatment of inferior pole patellar fractures in a finite element model.

METHODS

We conducted a finite element biomechanical study using two fixation methods: Ding's screw and tension band wiring (DSTBW) and cannulated screws and tension band wiring (CSTBW). Two methods were simulated to fix the inferior pole patellar fracture in a finite element model. The relative displacement and stress distribution were analyzed and compared.

RESULT

There were less displacement and stress distribution of DSTBW in different knee movement (30°, 60°, 90°, 120°) when compared to CSTBW. The highest value of displacement of the fracture and von Mises stress of the internal fixation happened in 120° knee movement in both groups. The highest displacement of the DSTBW was less than that of the CSTBW (1.92 mm to 2.12 mm). The highest value of the stress on the screws was 110.60 MPa in DSTBW group, and 132.90 MPa in CSTBW group. The highest value of the stress on the titanium cable was 38.51 MPa in DSTBW group, and 41.91 MPa in CSTBW group.

CONCLUSION

DSTBW fixation provides more stability than CSTBW fixation model in a finite element study.

Pin and Wire System Fixation for the Treatment of Comminuted Patella Fractures

We describe the wiring technique and evaluate the radiographic and clinical outcomes of treatment with a pin and wire system (PWS) for comminuted patella fractures. From June 2013 to October 2018, 33 patients with comminuted patella fractures were treated using a PWS. Open reduction and internal fixation was performed with multiple pins and a wire. All patients were allowed full weight bearing without a brace. Radiographs were obtained to evaluate bone union, implant breakage, back-out of pins, and intra-articular gaps and step-off. Clinical outcomes and postoperative complications were assessed at final follow-up examination. All fractures were united. Thirteen cable wires in 13 patients were partially broken without displacement of fracture at an average of 7.4 months (range, 1-19 months) postoperatively. The average preoperative, postoperative, and final follow-up intra-articular gap and step-off were 11.7 mm, 0.5 mm, and 0.03 mm and 6.6 mm, 0.4 mm, and 0.2 mm, respectively. The average postoperative pin displacement was 0.1 mm (range, 0-0.8 mm). Deep infection was not observed after the surgery. The implant removal rate was 21% (7 of 33). Among these, the symptomatic implant removal rate was 9% (3 of 33). Additionally, 3 of 7 patients with implant removal had broken wires. The average flexion and extension of knee joints were 139.7° (range, 120°-150°) and -0.9° (range, -10° to 0°), respectively. A PWS prevents back-out of the pins and reduces intra-articular gaps and step-off distances to acceptable levels, even if the cable wire is partially broken. Therefore, a PWS is a good treatment option for comminuted patella fractures. [Orthopedics. 2023;46(5):291-296.].

Management and Outcome of Elderly Patients With Patellar Fracture Treated With Novel Modified Cerclage Wiring

Introduction

The purpose of this study is to assess the efficacy and security of a fixation method for fixing patellar fractures in elderly patients utilizing modified cerclage wire.

Methods

From January 2015 to December 2020, 31 cases (age≥65 years old) of closed patellar fracture were treated by modified cerclage wiring. Patients in these instances ranged in age from 65 to 87 (73.7 ± 7.2 years), with 15 men and 16 women. 4 instances were type 34-C1 (transverse fracture) according to the AO/OTA classification, 27 cases (87%) were comminuted fractures, including 11 cases that were type 34-C2 (3 fragments), and 16 cases that were type 34-C3 (more than 3 fragments). Postoperative problems such as fragment re-displacement, nonunion, internal fixation loosening, infection, and internal fixation rupture were evaluated. The clinical grading systems of Böstman were used to assess the postoperative clinical outcomes.

Results

Thirty one patients in all were monitored for 14 to 31 months (22.2 ± 4.5 months). After the procedure, the fracture took 2.5-3.5 months (2.92 ± .25 months) to heal. There were no postoperative issues like infection, dislocation, implant breakage, uncomfortable hardware, or post-traumatic osteoarthritis. According to the clinical grading scales of Böstman, the average score of the final follow-up was 28.6 ± 1.1 (range 26-30). 29 (94%) of the patients had excellent results, whereas just 2 (6%) had good results. The patient's knee flexion activity ranged from 110 to 140°, making for a favorable prognosis.

Conclusion

Most patella fractures in the elderly are comminuted. Elderly patients with patellar fractures may be successfully treated with modified cerclage wire, with good results and no noticeable side effects.

Anterior variable-angle locked plating versus tension band wiring of simple and complex patella fractures - a biomechanical investigation

BACKGROUND

The aim of this study was to investigate the biomechanical performance of novel anterior variable-angle locking plates versus tension band wiring used for fixation of simple and complex patella fractures.

METHODS

Sixteen pairs of human cadaveric knees were used to simulate two-part simple transverse AO/OTA 34-C1 and five-part complex AO/OTA 34-C3 patella fractures. The complex fracture pattern was characterized with a medial and a lateral proximal fragment, together with an inferomedial, an inferolateral and an inferior fragment mimicking comminution around the distal patella pole. Eight pairs with simple fractures were split for fixation via either tension band wiring (TBW) through two parallel cannulated screws or anterior variable-angle locked plating, whereas other eight pairs with complex fractures were split for either TBW through two parallel cannulated screws plus circumferential cerclage wiring, or anterior variable-angle locked plating using a cortical caudo-cranial polar screw. Each specimen was tested over 5000 cycles with a range of motion from 90° flexion to full extension by pulling on the quadriceps tendon. Interfragmentary movements were captured by motion tracking.

RESULTS

For both fracture types, the longitudinal and shear articular displacements, measured between the proximal and distal fragments at the central patella aspect between 1000 and 5000 cycles, together with the relative rotations of these fragments around the mediolateral axis were all significantly smaller following anterior variable-angle locked plating versus TBW, p ≤ 0.01.

CONCLUSIONS

From a biomechanical perspective, anterior locked plating of both simple and complex patella fractures resulted in less interfragmentary displacement under extended cyclic loading.

3D reduction combined with the modified Kirschner-wire tension band for the treatment of comminuted patella fracture

PURPOSE

A novel 3D reduction method combined with a modified Kirschner-wire tension band (3D MKTB) fixation method to treat comminuted patella fractures was introduced in this study. This study aims to evaluate the effectiveness and practicality of this novel technology.

METHODS

This study is a retrospective case series study. Twenty-eight patients with closed comminuted patella fractures were treated with the novel 3D MKTB fixation method. Radiographs of the knee were obtained at the routine follow-up to assess fracture healing and widening of the articular step-off. Clinical outcomes including the degree of pain on a visual analogue scale (VAS), range of motion, Lysholm, and Bostman grading scales were measured at the last follow-up. The mean follow-up was 39.8 ± 10.5 (range 26-62) months.

RESULTS

All patients had bony union at a mean of 11.4 ± 1.4 (range 9-14 weeks) weeks based on X-ray. No patient had evidence of internal fixation failure. Only two patients suffered from surgical complication. One patient suffered from postoperative superficial infection, and one patient suffered from internal fixation irritation. Articular step-off larger than 2 mm was not seen in any cases. The average VAS-related pain score was 0.5 ± 0.5 (range 0-1) points. The average range of motion was 0-138.6° ± 11.9° (range 90°-155°), all patients had full knee extension. The mean Lysholm and Bostman scores were 92.9 ± 3.5 (range 86-100 points) points and 28.5 ± 1.3 (range 24-30 points) points, respectively.

CONCLUSION

The novel 3D reduction technique combined with the modified Kirschner-wire tension band technique is an effective, safe, and simple treatment option for comminuted patella fractures.

LEVEL OF EVIDENCE

IV.

Adjunct neutralization plating in patella fracture fixation: a technical trick

Patella fracture outcomes are positive overall; however, in some cases, traditional fixation methods result in complications, including loss of fixation and irritable hardware requiring removal. We present a technique of plate fixation that we believe has the potential to improve stability and is less offensive in more comminuted fracture patterns. Improved stability should allow unfettered advancement of rehabilitation without concern for loss of fixation. Lower profile fixation offers a potential for diminishing the presence of irritating hardware requiring removal. We present our technique for using plate fixation to augment more complex patella fracture patterns.

Treating Inferior Pole Fracture of Patella with Hand Plating System: First Clinical Results

OBJECTIVE

Inferior pole fractures of patella are notorious fractures where it is difficult to obtain rigid internal fixation by conventional methods. The objective of the study was to introduce the Hand Plating System (HPS), which was a novel surgical technique for inferior pole fractures of patella, and to report the radiological and clinical outcomes following the application of the surgical technique.

METHODS

The study was designed as a retrospective cohort study. Between July 2017 and December 2018, 30 patients who were diagnosed with inferior pole fracture of the patella without additional orthopaedic injuries were enrolled in this case series. After X-ray and 3D-CT examinations, all patients underwent open reduction and internal fixation by HPS with or without supplementary cannulated screw and lag screw stabilization. The bony union time, final range of motion (ROM), Bostman score, visual analog scale (VAS), and complications were measured as the clinical outcomes under a minimum of 12 months of follow-up.

RESULTS

All of the operations went well with the mean operative time of 76.2 ± 15.3 min. Bony union achieved in all the cases at an average of 9.5 ± 1.4 weeks after surgery. There was no loss of reduction, fixative failure, or surgical implant removal during follow-up. The average range of motion 1 year postoperatively was 0°-123.3°. The mean Bostman Score at the last follow-up was 26.8 ± 2.1 with the satisfactory rate of 100%. The pain feeling during walking as measured by VAS averaged at 0.9 ± 1.3. No complications developed except for one case of poor incision healing, which healed eventually after surgical debridement.

CONCLUSIONS

HPS was demonstrated as a secure fixation and as a kind of tension band for inferior pole fractures of the patella. Satisfactory recovery of knee function and low complication rate, including no need for hardware removal, could be expected.

Epidemiology, classification and treatment of patella fractures: an observational study of 3194 fractures from the Swedish Fracture Register

Background

Basic epidemiological data on patella fractures derived from large nationwide and multicenter studies are scarce. This observational register study describes patient epidemiology, fracture classification and treatment of patella fractures in adults in a Swedish population.

Methods

We conducted an observational study on data derived from the Swedish Fracture Register (SFR) on all patella fractures classified as non-periprosthetic and non-pathological, registered between 2014 and 2018 in individuals aged ≥ 18years. Epidemiological data on sex, age, side, seasonal variation, trauma mechanism, fracture classification (according to AO/OTA), and treatment were analyzed.

Results

3194 patella fractures were analyzed, occurring at a median age of 67 (range 19–100) years. 64% of all patients were female. Most fractures were caused by low-energy trauma, with 70% due to falling from a standing height. 1796 (56%) of the fractures were transverse compared to 845 (26%) vertical fractures. Most fractures (N=2148, 67%) were treated non-operatively. Operative treatment consisted mainly of Tension Band Wiring (TBW) performed in 774 (24%) patients.

Conclusions

Patella fractures mainly occur in elderly women (> 65 years), commonly caused by low-energy trauma. The main treatment is non-operative (67%), except for transverse (AO/OTA C3) fractures. TBW remains the most used operative treatment of choice. These results may help health care providers, researchers and clinicians better understand the panorama of patella fractures in Sweden.

Outcomes for a custom-made anchor-like plate combined with cerclage in the treatment of inferior pole patellar fracture

Objective

An inferior pole fracture of the patella requires surgical treatment to restore the knee extension mechanism of the knee joint. Different from other types of patellar fractures, inferior pole fractures are usually comminuted, and other traditional fixation methods, such as tension band wiring, may not meet the fixation needs. We propose fixing inferior pole fractures of the patella with a custom-made anchor-like plate combined with cerclage and report the surgical outcomes.

Material and methods

This is a retrospective clinical study. From June 2018 to August 2020, 21 patients with inferior patella fracture treated at Hong Hui Hospital Affiliated to Xi’an Jiaotong University received a custom-made anchor-like plate combined with cerclage. Complications of the surgical fixation methods and final knee function were used as the main outcome measures.

Results

All fractures achieved good union, and the union time ranged from 8 to 12 weeks. No patients had serious complications, such as internal fixation failure or infection. The average duration of surgery of patients was 75.05 7.26 min, and the intraoperative blood loss was 60.099.49 ml. At the last follow-up, the range of motion of the knee was 120°-140°, with an average of 131.436.92°, the Bostman score was 27–30, and the Lysholm score ranged from 82 to 95. All patients showed good knee function one year after the operation.

Conclusion

We used a modified T-shaped plate combined with cerclage technology to fix inferior fractures pole of the patella, providing reliable fixation, allowing early functional exercise of the knee joint, and providing patients with good knee joint function after surgery.

Functional and radiological outcomes following plating for displaced fractures of patella: A pilot study

INTRODUCTION

Patellar fractures constitute almost 1% of total skeletal injuries. Existing common operative methods include the use of different types of Tension band wiring techniques like cannulated screws and K-wires. The Patellar plating construct is a relatively newer operative method for patellar fracture fixation with promising outcomes with fewer complications.

METHOD

We conducted a pilot prospective study at our Apex Trauma center in twenty patients aged 18-65years with displaced patellar fractures, AO type A2, A3, B2, B3, C1, C2, C3. Fractures were fixed with low profile patellar plates (1.8 mm). Radiological and functional follow-up was done using X-rays, CT scans and BKS scoring (Bostman-Knee-Scale), Knee Society Score(KSS), and Tegner Lysholm knee scores respectively for two years.

RESULT

Mean functional outcome scores at 6 weeks, 3 months, 6 months and 2 years was 25.5, 28.3, 29.05 and 29.9 for BKS; 64.62, 84.12, 90.6, and 97.5 for KSS; 73.75, 89.7,94.8, and 99.3 for Tegner Lysholm knee score respectively. Radiological union, confirmed by CT scan, was observed in all patients at 3 months. Two patients had superficial surgical site infection (SSI) at 2 weeks. Implant impingement was also found in 2 patients at 3 months. None of the patients had a failure of fixation at the end of the study.

CONCLUSION

Patients with low profile patellar plate constructs have favorable clinical and radiological outcomes with minimal non-specific complications.

Plate osteosynthesis in patellar fractures: a systematic review and meta-analysis

INTRODUCTION

To perform a systematic review and assess the indications, outcomes, complications, and union rates associated with plate osteosynthesis in patellar fractures compared to tension band wiring.

METHODS

The systematic search was conducted for articles in PubMed, Embase Biomedical, Cochrane central, and LILACS databases (date of inception to July 30, 2020). Articles were included if they were randomized control trials, cohort studies, case-control studies, and case series (with more than five cases), which focused on the clinical outcomes of patients with plate osteosynthesis as a treatment for fracture of the patella and had a minimum follow-up of 3 months. All studies were assessed according to their level of evidence, the number of patients, age of patients, fracture patterns described, complications of treatment, and results summarized. Meta-analysis could only be done for two parameters (complications and reoperations) due to the paucity of data and heterogeneity of studies' limited statistical analysis. The data are presented as a review table with the key points summarized.

RESULTS

Twenty studies (seven prospective and 13 retrospective articles) identified 533 patients with 534 fractures who had undergone plate osteosynthesis for fracture of the patella. The most common fracture treated with plate osteosynthesis was 34C.

CONCLUSION

Basket plate was most commonly used for inferior pole fractures, while mesh plates were for intra-articular patella fractures. Overall plating was associated with better clinical outcomes, fewer complication rates, and high union rates compared to tension band wiring for patella fractures.

Comparison between tension band and cerclage with X-Plate and lag screws in treatment of comminuted patellar fractures

BACKGROUND

Comminuted patellar fractures are not rare, and the ideal treatment method remains controversial. The present study was conducted to evaluate effects and compare complications of two different methods used to treat comminuted patellar fractures.

METHODS

From March 2010 to August 2016, 102 cases of 34-C2 or 34-C3 comminuted patellar fractures were treated at our hospital, wherein patients received two different treatments: titanium cable tension band with cerclage method (group A) and intrafragmentary screws with X-shaped plating technique (group B). At follow-ups, articular step-off, range of motion (ROM), Lysholm scores, time of union, and complications were recorded and analyzed. Radiographic and clinical data as well as rate of complications were statistically analyzed.

RESULTS

In total, 87 patients were included in the final analysis (n = 47 in group A and n = 40 in group B). No significant differences were noted in terms of cost of implant, age, gender, rate of 34-C3 fractures, rate of layered inferior pole fractures, postoperative articular step-off and union time. At 2-year follow-up, average Lysholm scores, ROM and rate of complications were (89.0 ± 4.5), (122°±12°) and (27.7%) in group A and (90.2 ± 3.9), (124°±11°) and (17.5%) in group B, respectively, with no significant differences (p > 0.05). The mean time of surgery in group B was shorter than that in group A with significant difference (p < 0.05).

CONCLUSIONS

Treatment using the intrafragmentary screws and plate method for amenable comminuted patellar fractures achieved similar complication rate and favorable functional outcomes at the 2-year follow-up, which was comparable to the titanium cable tension band with cerclage method. Thus, the intrafragmentary screws and plate method is effective, safe and convenient for 34-C2/C3 comminuted patellar fractures, especially appropriate for patients with layered fragments.

Patella Fractures: Approach to Treatment

Patellar fracture morphology varies based on the mechanism of injury. Most fractures are either a result of direct impact or through an indirect eccentric extensor contraction injury. Each fracture pattern requires appropriate preoperative planning and individualization of the fixation method. Displaced fractures affect the extension apparatus, and often require surgical fixation. Surgical treatment is recommended in fractures with any of the following features: articular step-off > 2 mm, > 3 mm of fracture displacement, open fractures, and displaced fractures affecting the extensor mechanism. Meticulous handling of the soft-tissue envelope is of the utmost importance, given the patella's tenuous blood supply and limited soft-tissue envelope. Incongruent articular surface can result in detrimental long-term effects; therefore, surgical treatment is directed toward anatomic reduction and fixation. The evolution of patellar fracture fixation continues to maximize options to balance rigid fixation with low-profile fixation constructs. Improving functional outcomes, minimizing soft-tissue irritation, and limiting postoperative complications are possible by using the therapeutic principles of rigid anatomical fixation and meticulous soft-tissue handling.

[Effectiveness of multidirectionally three-dimensional steel wire ring sleeve fixation in treatment of inferior patellar pole avulsion fractures]

Objective

To explore the method and effectiveness of multidirectionally three-dimensional steel wire ring sleeve fixation in the treatment of inferior patellar pole avulsion fractures.

Methods

Betweern January 2015 and January 2019, 22 patients with inferior patellar pole avulsion fractures were admitted and treated. There were 12 males and 10 females. The age ranged from 20 to 69 years, with an average age of 39.4 years. The causes of injury included 9 cases of traffic accident and 13 cases of falling. All of them were unilateral closed injury of knee joint, including 7 cases of skin contusion around patella. Preoperative range of motion of the affected knee was (20.82±7.16)° (range, 10°-35°). The time from injury to operation ranged from 3 to 12 days, with an average of 5.9 days. During the operation, the inferior patellar avulsion fracture was reduced with forceps; the patella was circumferentially ligated through the distal bone surface of the fracture with 0.8 mm diameter steel wire; then 3 longitudinal bone tunnels were made in the upper patella, respectively. The 0.8 mm diameter steel wire passed through the bone tunnel, and the longitudinal ring was attached to the ring to fix the upper and inferior patellar fracture. Tighten the transverse and longitudinal rings with No.2 tendon suture line, then longitudinally ringed and sutured to strengthen the patella. The knee range of motion, fracture healing time, and complications were recorded. The functional recovery of the knee joint was evaluated by Böstman score.

Results

All incisions healed by first intention, and no incision related complications occurred. All the 22 patients were followed up 13 months to 5 years with an average of 26.7 months. The fracture healing time was 9-12 weeks (mean, 10.9 weeks). At last follow-up, the knee range of motion was (129.77±2.35)° (range, 126°-135°), showing significant difference when compared with preoperative one ( t=-67.022, P=0.000). The Böstman score ranged from 31 to 36, with an average of 34.3. No reduction loss, fracture of steel wire, failure of internal fixation, and other complications occurred during follow-up.

Conclusion

Multidirectionally three-dimensional steel wire ring sleeve fixation in the treatment of inferior patellar pole avulsion fractures has the advantages of reliable fixation, early functional recovery, and fewer complications, so the effectiveness is satisfactory.

A retrospective cohort study on prevalence of postoperative complications in comminuted patellar fractures: comparisons among stabilized with Cannulated-Screw, Kirschner-Wire, or Ring-Pin Tension Bands

Background

Displaced patellar fractures are commonly treated with open reduction and fixation with several different types of tension-band (TB) constructs. The main objective of this study was to compare the prevalence of postoperative complications after surgical stabilization of comminuted patellar fractures with either a modified Kirschner-wire tension band (MKTB), a cannulated-screw tension band (CSTB), or a ring-pin tension band (RPTB).

Methods

We conducted a retrospective and consecutive cohort study of comminuted patellar fractures (n = 334) stabilized using a TB construct. Postoperative premature loss of reduction, infection, and skin breakdown were compared according to the type of TB constructs received (MKTB, CSTB, or RPTB). The rate of implant removal due to symptomatic hardware was also evaluated.

Results

Fixation failure rate was significantly different among the groups (P = 0.013), with failure rates of 4.7% observed in the MKTB group,14.5% in the CSTB group, and 4.9% in the RPTB group. Skin breakdown and infection were not significantly different among the groups (Ps > 0.05). Due to symptomatic hardware, 40.5% of the patients in the MKTB group, 22.9% in the CSTB group, and 24.3% in the RPTB group underwent implant removal (P = 0.004). After adjusting for age, gender, comorbidities, number of supplementary screws/K-wires, and use of cerclage cables, multivariate regression analysis revealed that CSTB contributed to a 2.08-times greater risk of fixation failure compared to RPTB, while MKTB and RPTB were similar in risk of failure. In addition, it was found that patients who underwent MKTB fixation were more than twice as likely to undergo implant removal for symptomatic hardware compared with RPTB (odds ratio = 2.11, 95% CI = 1.20 to 3.72; P = 0.010).

Conclusions

RPTB have advantage over MKTB and CSTB fixation in terms of symptomatic hardware and premature failure, respectively.

Level of evidence

Therapeutic Level III

Functional Outcomes of Patella Fractures Treated With Anterior Plate Osteosynthesis at One Year

OBJECTIVES

To evaluate the functional outcomes of patients with displaced patellar fractures treated with anterior plate constructs.

DESIGN

Prospective cohort and retrospective clinical and radiographic assessment.

SETTING

Level I Trauma Center.

PATIENTS/PARTICIPANTS

Between 2014 and 2018, 18 patients who underwent operative intervention for an isolated, displaced patella fracture (OTA/AO 34C1-3) with a minimum of 1-year follow-up agreed to participate in the study. The mean follow-up was 19.5 ± 6.0 months.

INTERVENTION

Patients were treated with 2.4 or 2.7-mm plates and supplemental screws or cerclage wires.

MAIN OUTCOME MEASUREMENTS

Patients were evaluated with the Short Form-36 Survey and the Knee Injury and Osteoarthritis Outcome Scores and asked about symptomatic implants. The range of motion was assessed by goniometer.

RESULTS

The cohort had no wound complications, infections, nonunion, loss of reduction, or implant failure. Active knee flexion was 131 ± 7 degrees. Five patients (28%) endorsed implant irritation. Only one patient (5.5%) underwent implant removal, which consisted of transverse screw removal alone. Twelve of the 14 patients (86%), who were previously employed, returned to work at 10 ± 7 weeks. All Knee Injury and Osteoarthritis Outcome Scores subscale scores and the Short Form-36 Survey scores for physical functioning, limitations due to physical health, limitations due to mental health, and social functioning were significantly lower than reference population norms (P < 0.05).

CONCLUSIONS

Anterior plating provides reliable fixation for displaced patellar fractures and results in a low incidence of implant irritation. However, patients who had anterior fixation for displaced patella fractures continue to exhibit functional deficits at 1-year postoperatively.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

[Current treatment standard for patella fractures in Germany]

BACKGROUND

The treatment of patella fractures is technically demanding. Although the radiological results are mostly satisfactory, this often does not correspond to the subjective assessment of the patients. The classical treatment with tension band wiring with K‑wires has several complications. Fixed-angle plate osteosynthesis seems to be biomechanically advantageous.

OBJECTIVE

Who is treating patella fractures in Germany? What is the current standard of treatment? Have modern forms of osteosynthesis become established? What are the most important complications?

MATERIAL AND METHODS

The members of the German Society for Orthopedics and Trauma Surgery and the German Knee Society were asked to participate in an online survey.

RESULTS

A total of 511 completed questionnaires were evaluated. Most of the respondents are specialized in trauma surgery (51.5%), have many years of professional experience and work in trauma centers. Of the surgeons 50% treat ≤5 patella fractures annually. In almost 40% of the cases preoperative imaging is supplemented by computed tomography. The classical tension band wiring with K‑wires is still the preferred form of osteosynthesis for all types of fractures (transverse fractures 52%, comminuted fractures 40%). In the case of comminuted fractures 30% of the surgeons choose fixed-angle plate osteosynthesis. If the inferior pole is involved a McLaughlin cerclage is used for additional protection in 60% of the cases.

DISCUSSION

The standard of care for patella fractures in Germany largely corresponds to the updated S2e guidelines. Tension band wiring is still the treatment of choice. Further (long-term) clinical studies are needed to verify the advantages of fixed-angle plates.

Comminuted patellar fractures: The role of biplanar fixed angle plate constructs

Background

Comminuted patellar fractures represent a challenging clinical problem. Treatment aims to restore the integrity of the extensor mechanism and the congruity of patellofemoral joint. Controversy exists regarding the ideal fixation method. Metallic constructs aiming to convert pulling forces on the anterior aspect of the patella into compression forces across the fracture site are the standard of care. More recently, low profile plates have been described in the management of comminuted patellar fractures. The aims of this study were to (1) develop a novel unstable patellar fracture model and (2) to compare biomechanically three different constructs for fixation comminuted patellar fractures. We hypothesized that an orthogonal biplanar disposition of the screws within an anteriorly placed locking plate provides the best biomechanical properties in the management of comminuted fractures.

Methods

Six-part complex AO 34–C3 patella fractures were simulated in 18 human cadaveric knees by means of osteotomies including comminution around the distal patellar pole. The specimens were randomly assigned to 3 fixation techniques (n ​= ​6) for either anterior plating, antero-lateral plating, or tension band wiring (TBW). Biomechanical testing was performed over 5000 cycles in active extension and passive flexion, followed by ultimate destructive quasi-static testing. Interfragmentary movements were captured by means of optical motion tracking.

Results

Displacement between the proximal and distal medial patella fragments was lower after anterior plating compared to both antero-lateral plating (P ​= ​0.084) and TBW (P ​< ​0.001). Moreover, displacement between the proximal and distal lateral fragments was significantly lower after anterior plating compared to both other techniques (P ​≤ ​0.032). In addition, it was significantly lower for antero-lateral plating versus TBW (P ​< ​0.001). Rotation around the medio-lateral axis between the proximal and distal medial fragments was significantly lower after anterior plating compared to TBW (P ​= ​0.017).

Conclusions

Anterior mesh plating with biplanar placement of locking screws provides superior stability for fixation of comminuted patellar fractures when compared to both antero-lateral mesh plating and TBW. The latter is associated with considerably inferior performance.

Clinical outcomes of Ti-Ni shape-memory patella concentrator combined with cannulated compression screws in the treatment of C2 and C3 patella fracture: a retrospective study of 54 cases

Background

Ti-Ni shape-memory patella concentrator (TNSMPC) has been designed as an alternative approach for fixation of patella fracture, which has some advantages like higher hardness, higher tenacity, better wearing resistance, excellent corrosion resistance and desired histocompatibility. The present study was to investigate the efficiency of TNSMPC combined with cannulated compression screws in the treatment of comminuted patella fractures.

Methods

Between January 2014 and December 2017, 54 patients of C2 and C3 patella fractures underwent open reduction and internal fixation with TNSMPC combined with cannulated compression screws. All the patients got standard postoperative rehabilitation programs and were regularly followed up for at least 12 months after the operation. X-rays, knee functions and life quality were evaluated during the follow-up.

Results

All the patients achieved bone healing and recovery of knee function with low incidence of complications according to outcomes of X-rays and questionnaires. The average operation time and blood loss during surgery were 77.5 ± 25.12 min and 24.25 ± 4.70 ml respectively. The Knee Outcome Survey Activities of Daily Living Scale, the range of motion and the 36-item short-form heath survey after the operation were all improved. According to the Bostman’s criteria, the excellent to good rate was 92.6%.

Conclusion

TNSMPC combined with cannulated compression screws is an effective internal fixation method for C2 and C3 patella fracture with excellent clinical outcomes. In addition, the operation does not increase extra technique difficulty or tissue damage relatively, which is worth promotion.

Contouring Plates in Fracture Surgery: Indications and Pitfalls

Effective fracture surgery requires contouring orthopaedic implants in multiple planes. The amount of force required for contouring is dependent on the amount and type of material contained within the plane to be altered. The type of contouring used depends on the desired plate function; for example, buttress mode often requires some degree of undercontouring, whereas compression plating may require prebending. Other reasons to contour a plate include matching patient anatomy either to maximize fixation options or to reduce implant prominence. Precontoured plates can be convenient and help to facilitate soft-tissue friendly techniques but have the potential to introduce malreduction if the plate position and fit are not carefully monitored.

Percutaneous cerclage wiring for type 34-C patella fracture in geriatric patients

PURPOSE

This study was to retrospectively evaluate clinical outcomes of geriatric patients with patella fracture treated by percutaneous cerclage wiring and to introduce the surgical technique.

METHODS

From January 2009 to December 2015, fifty-seven consecutive geriatric patients of type 34-C patellar fracture underwent closed reduction and percutaneous cerclage wiring fixation in our hospital. Visual Analog Scale (VAS) score, Levack score system, WOMAC test form of pain, stiffness and function, and knee joint range of motion (ROM) were applied for functional evaluation.

RESULTS

Fifty-three patients were followed up for a mean period of 36 months (12 to 82 months). All fractures were unioned, no wound infection, second displacement of fracture fragment or wire migration was found. Wire breakage happened in one case at six months post-operation. Thirteen patients had hardware removed, nine cases for implant irritation at the knot and four cases for no specific reason. No patient developed postoperative knee stiffness, and range of motion was 128.6° (110-140). The average VAS score of emotional knee function was 87.5 (65-99) preinjury and 78.1 (53-95) at the last follow-up. 86.8% (46/53) patients considered that they regained more than 80% of their knee function. The average Levack score was 10.0 (6-12), which included thirty-five evaluations of "excellent" and eighteen of "good". The average WOMAC score was 21.3 (13-37).

CONCLUSIONS

Percutaneous cerclage wiring fixation is a viable option for type 34-C patella fracture in geriatric patients.

Modified tension band wiring of patellar fracture as a technique to minimize postoperative complications: A case report

RATIONALE

Tension band wiring is the most widely accepted technique for the treatment of patellar fractures but the technique is associated with common complications like wire migration, prominence, and breakage. To reduce these complications, we developed and propose a modified technique that has a superior biomechanical strength and a potential to reduce such postoperative complications.

PATIENT CONCERNS

The patient presented with pain and mild swelling in his left knee after he slipped on the floor and fell on his left knee. He has no significant past medical or surgical history. The patient took the tension band wiring as the first choice because of the wide acceptance. But he worried about the complications.

DIAGNOSES

X-ray showed a transverse fracture of the left patella with an inferior pole occult fracture.

INTERVENTIONS

The patient was operated with a modified technique of the classic tension band wiring for patellar fractures. In our 4-step procedure, double tension cerclage wires were wrapped under the exposed ends of the Kirschner wires (K-wires) and the tendons in figure-of-8 fashion. The aim was to increase the biomechanical strength so that when one of the tension wires fail, the other one can hold the fragments together.

OUTCOMES

The patient recovered very well and without any complications. The patient was followed-up for 1 year and the fracture has united very well, with satisfying knee range of motion.

LESSONS

From this case study, we can detect the biomechanical advantages of our technique which can increase the stability of the fracture and that allows early functional exercise and additionally the micromotion at the fracture site has a beneficial effect of fracture union. Based on the perfect outcomes, our technique is worthy of clinical application.

Combination of a miniplate with tension band wiring for inferior patellar pole avulsion fractures

BACKGROUND

The tension-band technique, with Kirschner wires or cannulated screws, is one of the most commonly used fixation techniques for patellar fractures. However, it may be not useful for inferior patellar pole fractures as it may lead to fragment reduction loss and fixation failure. We present a surgical technique that combines a miniplate with tension band wiring for inferior patellar pole avulsion fractures and report surgical outcomes.

PATIENTS AND METHODS

Between June 2012 and May 2016, 17 consecutive patients (mean age: 51 years) with inferior patellar pole fractures (AO/OTA 34-A1) were treated operatively with a miniature plate in combination with tension band wiring. The final range of motion, bone union time, and Bostman score were the primary outcome measures.

RESULTS

The bone union time was 9.5 weeks on average after surgery (range: 8-12 weeks). No patient had loss of reduction or implant failure. There were no cases of irritation or other complications from the implant. At the final follow-up, the average range of motion arc was 128.24° (range: 105-140°). The mean Bostman score at the last follow-up was 28.1 points (range: 25-30 points). All patients showed excellent or good results 1 year after surgery.

CONCLUSION

The combination of a miniplate with tension band wiring for inferior patellar pole avulsion fractures provides stable flexion, allows for early range of motion, and provides excellent results in terms of knee function.

Patella fractures treated with cannulated lag screws and fiberwire® have a high union rate and low rate of implant removal

OBJECTIVES

The purpose of this study is to report the results of open reduction internal fixation of patella fractures (OTA 34 A-C) using cannulated lag screws and FiberWire® (Arthrex, Naples, FL, USA) with regard to union and symptomatic implant removal.

DESIGN

Retrospective review of prospectively collected database.

SETTING

Urban Level 1 trauma center and Level 2 trauma center METHODS: All displaced intra-articular patella fractures (OTA 34 A-C) treated with ORIF by cannulated lag screws and FiberWire® tension band/cerclage between January 1, 2009 and August 1, 2018. Three hundred and eighty seven consecutive patients were identified. Fifty fractures were included in the final analysis.

MAIN OUTCOME MEASUREMENT

All patients were followed to clinical and radiographic union. Nonunion was defined as lack of clinical and radiographic union, fracture displacement, and/or return to OR for revision surgery. Rate of symptomatic implant removal was recorded.

RESULTS

Average age was 57.7 years (range 21-86). Average follow up was 20.6 months (range 6-98 months). Average time to clinical and radiographic union was 3.1 months (range 3-7 months). Four fractures were open. There was a 96% (48/50) rate of primary union, with one patients requiring revision surgery to achieve union, and one developing an asymptomatic radiographic nonunion. The rate of symptomatic implant removal was 8% (4/50). Only 1 of the 4 was operated for a prominent suture knot, and the remaining 3 were for prominent screw removal. Knee range of motion averaged 0.37° extension to 119° flexion (range, 0-150°).

CONCLUSION

Patella fractures can be treated with cannulated lag screws and FiberWire® with a high rate of primary union (96%) and a low rate of symptomatic implant removal (8%). The implant removal rate compares favorably with alternative constructs, with an equivalent rate of fracture union.

Hook plating in patella fractures

PURPOSE

Tension band wiring is considered the standard treatment for patella fractures. However, it is limited for fractures with marginal involvement, comminution, and osteoporotic bone. Our experience indicates that these limitations can be overcome with the hook plate. We evaluated the radiographic and clinical outcomes in patients with patella fracture treated with hook plating.

METHODS

We enrolled 30 patients who underwent hook plating for patella fracture at two institutions between 2013 and 2017. Fracture classification and surgical options were reviewed. Postoperative fracture gap and time to union as radiographic measurements, and complications, range of motion, and functional outcome with the Lysholm score as clinical outcomes, were evaluated retrospectively.

RESULTS

Nine fractures were AO/OTA 34A1, three B1, one B2, two C1, nine C2, and six C3. All were closed fractures. There were 3 cases of revision, 4 with lateral or medial marginal fracture, 9 with isolated inferior pole fracture, and 14 with comminuted fracture. The average postoperative fracture gap was 0.4 (range, 0-2.0) mm, and bone union was achieved without additional intervention. The average time to union was 11.6 (range, 7-24) weeks. There were no complications, and no extension lag except in one case (10°). The average flexion was 138.5° (range, 110-145°). For functional outcomes, the average Lysholm score was 89.5 (range, 74-95), with 13 excellent, 14 good, 3 fair, and no poor cases.

CONCLUSION

This study suggests that hook plating can result in good bone union and restored knee function in marginal or comminuted fractures of the patella.

Off-Label Use in Orthopaedic Surgery

Surgeons frequently use orthopedic devices in an off-label manner. It is the responsibility of the surgeon to be familiar with the product and to use it based on scientific and clinical rationale. However, such practices are poorly publicized, and there remains paucity in the current literature surrounding the off-label use of orthopedic devices. Furthermore, the off-label use of devices is fraught with difficulty, including limitations in investigational studies and insurance reimbursement or coverage of use. Surgeons should be aware of the common off-label use in orthopedics. This review provides an overview of the off-label use in orthopedics and the obstacles associated with it; this review also offers clinical examples of its implementation.

Miniplate Augmented Tension-Band Wiring for Comminuted Patella Fractures

The aim of this study was to introduce various applications of miniplate augmented tension-band wiring (TBW) for comminuted patella fractures and to evaluate the clinical outcomes. Comminuted articular patella fractures were managed with anterior cortical miniplate fixation with a TBW technique from January 2014 to January 2016. The primary end point was radiographic union. Secondary end points were complications related to the procedure. Functional outcomes including range of motion were also evaluated. Thirty patients were followed up for a mean of 20 months (range, 12-28) postoperatively. The primary union rate was 96% (29 of 30 patients). Mean time to union was 3.2 months. One patient required additional surgery because of acute postoperative infection. Twenty-five patients recovered a full range of motion relative to the contralateral limb. The mean Bostman score at the last follow-up was 28.6 points (range, 26-30). In conclusion, miniplate augmented TBW is a versatile and useful technique for comminuted patella fracture fixation.

A clinical comparison study of three different methods for treatment of transverse patellar fractures

BACKGROUND

Tension bands structures are widely used to treat transverse patellar fractures. However, many implants-related complications have been reported. The purpose of this study is to evaluate effects and compare complications of three methods used to treat transverse patellar fractures, including titanium cable tension bands, compression screws with titanium cable cerclage, and X-shaped plating technique.

METHODS

From January 2010 to March 2016, 120 cases of transverse patellar fracture received open reduction and internal fixation with one of three methods: titanium cable tension band (group A), compression screws with titanium cable cerclage (group B), and X-shaped plating technique (group C). Of these, 108 cases were followed for >2 years. Clinical and radiographic data were retrospectively collected and statistically compared.

RESULTS

Final analysis included 108 patients (n = 38 in group A, 36 in B, and 34 in C). Reduction was satisfactory in all patients after surgery. No significant differences were noted in age, gender, time from injury to surgery, postoperative articular step-off, Lysholm score, and range of motion at 24 months among all groups. At final follow-up, 12 (31.6%) symptomatic implant complications were encountered in group A, along with 6 (16.7%) and 2 (5.9%) in groups B and C, respectively (p < 0.05).

CONCLUSION

All three methods could achieve the goal of rigid fixation and early functional rehabilitation. However, the X-plate technique had the lowest risk of symptomatic implant complications and could thus be a safe and effective alternative for internal fixation of transverse patellar fractures.

Treatment of Patella Fractures

Patella fractures comprise 1% of all fractures. Treatment options vary based on fracture displacement, classification, and patient factors. Traditionally, nonoperative treatment has been reserved for nondisplaced fractures. Many operative treatments are available with differing indications and levels of success. Tension band constructs have been the most commonly employed approach to fixation, with cerclage wiring for comminuted fractures. Recently, plate fixation of patella fractures has become more popular. Plating constructs offer a low-profile design with stable fixation, allowing for earlier mobilization and potentially improved functional outcomes. Data regarding the long-term outcomes of plating techniques are limited, and further studies are needed. [Orthopedics. 2018; 41(6):e747-e755.].

Failure of Patellar Plating with Mini-Fragment Implants: A Case Report

CASE

A 40-year-old woman presented to the emergency department with a comminuted fracture of the patella with separation of the bone fragments. The patient underwent an open reduction and osteosynthesis using medial and lateral 2.0-mm nonlocking plates, which subsequently led to pain in the anterior and posterior aspects of the knee.

CONCLUSION

In this patient, bicolumnar nonlocking plating was unable to adequately resist the tensile forces of the extensor mechanism. We believe that the probable cause of failure was an insufficient neutralization of the tensile forces exerted by the extensor mechanism. Because of the substantial forces acting on the patella, a method of converting these tensile forces into compressive forces is very beneficial, as seen with anterior tension-band wiring. Although we used nonlocking plates in our patient, we believe that locking-plate fixation placed along the medial and lateral columns also would have had a biomechanical disadvantage in dispersing the tensile forces exerted by the extensor mechanism.

Fixed angle plate fixation of comminuted patellar fractures

INTRODUCTION

Comminuted patella fractures are uncommon and difficult fractures to manage. Multiple treatment modalities have been suggested, with little clinical data to support practice. Recent biomechanical and technical investigations have described successful plate fixation of comminuted patella fractures. The purpose of this study was to evaluate radiographic, clinical and functional outcome of comminuted patella fractures treated with a fixed angle locking plates. We believe stable fixation, which results in successful fracture union and functional recovery, can be achieved with this technique.

MATERIALS AND METHODS

A retrospective review was performed at a single regional academic Level 1 trauma hospital. All comminuted patella fractures treated with a fixed angle locking plate (AO/OTA 34C2 and C3) over a six-year period were evaluated. Thirty-six patients were identified. Average length of follow up was 154 weeks (range 12-297 weeks). Twenty patients were available for functional outcome scoring. Primary outcome measures were: Knee Outcome Score (KOS), Lower Extremity Functional Scale (LES) and goniometer measured knee range of motion. Secondary outcomes evaluated the need for additional screw or cerclage fixation, reoperation for any reason, bothersome hardware, infection and nonunion.

RESULTS

Average KOS = 57.2 (20-74), average LES = 58.9 (15-80). Median extension = 0° (full extension), median flexion = 130°. Supplemental screws were used in 17/36 cases; cerclage used in 2/36 cases. Hardware irritation was noted in 4/20 patients, no patient requested elective hardware removal, one patient had failure of fixation and no nonunions were identified.

CONCLUSION

Fixed angle plate stabilization of comminuted patella fractures is a viable technique for fracture fixation. Good to excellent return of knee function and low complication rates, including need for hardware removal, can be expected.

Treating patella fractures with a locking patella plate - first clinical results

The standard treatment for patella fractures is tension band wiring. However, with tension band wiring anatomical reduction and rigid fixation can be challenging and the clinical outcome after patella fracture is often not satisfying. The purpose of this prospective clinical observation was to evaluate the clinical outcome in patients with patella fractures treated with an angular stable patella plate. Between 2011 and 2015 a total of 67 patients were treated with an angular stable patella plate. Outcome in these patients was evaluated by the Knee Outcome Survey Activities of Daily Living Scale (KOS-ADL) and range of motion of the knee joint was assessed. Complete follow up was obtained for 35 patients. In these patients, we found one implant-related complication. None of the patients reported any deficits in extension capabilities. The flexion was on average 127° (SD 21°). The patients classified the function of their knee in daily life on average with 77% (SD 24%) in comparison to their function before the trauma. Only kneeling or squatting was a problem in some patients. In conclusion, angular stable patella plating appears to be a promising alternative treatment for patella fractures. The patella plate provides increased mechanical stability for fracture fixation which appeared to result in a reduction of complications and improvement of functional outcome compared to tension band wiring. Especially patients with a multi-part or comminuted fracture or with osteoporotic bone are likely to benefit from the stability provided by the plate and the locking screws.

Treatment of displaced transverse fractures of the patella: modified tension band wiring technique with or without augmented circumferential cerclage wire fixation

BACKGROUND

Displaced transverse fractures of the body of the patella are usually associated with disruption of extensor mechanism and should be fixed surgically. The most common method is a tension band wiring (TBW) technique. Some surgeons concurrently employ an augmented circumferential cerclage wiring (ACCW) technique to help fracture stabilization and aid in fracture healing; however, its role and effect on the treatment outcomes is unclear.

METHODS

We performed a STROBE-compliant retrospective observational cohort study on all cases of acute closed patella fracture that were treated at our institution between 2006 and 2012. Of 185 episodes, 72 (38.9%) were eligible for this study according to our inclusion/exclusion criteria. We classified these subjects with AO/OTA type 34-C1.1 or 34-C2 lesions into two groups for analyses: fractures treated with modified TBW and ACCW (group 1, n = 27) and those treated with modified TBW alone (group 2, n = 45). Plain radiographs were used to evaluate radiographic outcomes and the effect of potential risk factors on fixation failure was analyzed by subgroup comparisons.

RESULTS

Our results revealed that there were no significant differences in the rates of fixation failure (P = 0.620), nonunion (P = 0.620), and revision surgery (P = 0.620) between the groups. Although not statistically significant, there was a trend towards a positive risk association between fixation failure and age distribution > 60 years (10.0% vs. 0.0%, P = 0.124; OR = 8.0, P = 0.168) and > 70 years (9.4% vs. 2.5%, P = 0.321; OR = 4.0, P = 0.237) and the superficial level of the K-wires (12.0% vs. 1.5%, P = 0.117; OR = 6.3, P = 0.121). Regarding those modified TBW patients concurrently treated with an ACCW, the potential risk association between fixation failure and the superficial level of the K-wire was prone to increase further (28.6% vs. 0.0%, P = 0.060; OR = 18.6, P = 0.071).

CONCLUSIONS

Concurrent application of an ACCW might be needless and not efficacious to help fracture stabilization and healing in patients having been treated with modified TBW for displaced transverse fractures of the body of the patella. Adherence to correct surgical technique such as putting the K-wires at the proper level and securing control of the both ends of the K-wires may be more important and help in improving outcomes.

Treatment of Patellar Lower Pole Fracture with Modified Titanium Cable Tension Band Plus Patellar Tibial Tunnel Steel "8" Reduction Band

Purpose: To determine the efficacy of modified titanium tension band plus patellar tendon tunnel steel 8 "reduction band" versus titanium cable tension band fixation for the treatment of patellar lower pole fracture. Materials and Methods: 58 patients with lower patella fracture were enrolled in this study, including 30 patients treated with modified titanium cable tension band plus patellar tibial tunnel wire "8" tension band internal fixation (modified group), and 28 patients with titanium cable tension band fixation. All patients were followed up for 9∼15 months with an average of 11.6 months. Results: Knee flexion was significantly improved in the modified group than in the titanium cable tension band group (111.33 ± 13 degrees versus 98.21 ± 21.70 degrees, P = 0.004). The fracture healing time showed no significant difference. At the end of the follow-up, the improvement excellent rate was 93.33% in the modified group, and 82.14% in the titanium cable tension band group. Titanium cable tension band internal fixation loosening was found in 2 cases, including 1 case of treatment by two surgeries without loose internal fixation. Conclusions: The modified titanium cable tension band with "8" tension band fixation showed better efficacy for lower patella fractures than titanium cable tension band fixation.

Management of displaced inferior patellar pole fractures with modified tension band technique combined with cable cerclage using Cable Grip System

INTRODUCTION

We present a modified tension band technique combined with cable cerclage using Cable Grip System for the treatment of displaced inferior patellar pole fractures and report the knee functional outcome.

PATIENTS AND METHODS

The patients who had had operative treatment of a displaced inferior patellar pole fracture (AO/OTA 34-A1) between December 2013 and December 2015 were studied retrospectively. Eleven consecutive patients had had open reduction and internal fixation with the modified technique using Cable Grip System, of whom, five males and six females with an average age of 60.9 years (range, 29-81 years). All fractures occurred from direct fall onto the knee. The average time from injury to surgery was 6.1days (range, 2-12days). The range of motion (ROM) was measured in degrees by goniometry at postoperative intervals of 1, 2, 4, 12, and 48 weeks; Knee function was evaluated using the Rasmussen scores at final follow-up.

RESULTS

No patients had nonunion, loss of reduction, migration of wire, irritation from the implant and fixation breakage during the follow-up period. Recovery of ROM was achieved at 12 weeks, with the average ROM at 1 week was 72° (range, 65°-78°), 86.4° (range, 78°-92°) at 2 weeks, 115.5° (range, 103°-122°) at 4 weeks, 129.6° (range, 122°-133°) at 12 weeks, 134.5° (range, 129°-139°) at 48 weeks after the operation. Concerning the knee function outcome assessment, all patients showed excellent results at final follow-up. The average Rasmussen scores was 27.9 out of 30 (range, 27-29).

CONCLUSIONS

The modified tension band technique combined with cable cerclage using Cable Grip System for displaced inferior patellar pole fractures can provide stable fixation with excellent results in knee function, allows for immediate mobilization and early weight-bearing, which is a simple and valuable technique in routine clinical practice.

Comminuted Patella Fracture in Elderly Patients: A Systematic Review and Case Report

Objectives:

To review comminuted patella fracture in the elderly patients and examine the surgical options to avoid complications such as fixation failure and poor functional outcome. To provide an example of mesh augmentation in comminuted patella fracture in the elderly patients.

Data Sources:

A literature review was conducted by the authors independently using Ovid, Medline, Cochrane, PubMed, and Clinical Key in English. We aimed to review data on patients older than 65 with comminuted patella fracture. Search conducted between July and December 2015.

Study Selection:

Search terms included patella fracture, elderly, and fixation failure. Abstracts were included if they were a case report, cohort series, or randomized control trial. Further inclusion criteria were that they were available in full text and included patient age(s), operative details, follow-up, and outcome discussion.

Data Extraction:

Each study was assessed according to its level of evidence, number of patients, age of patients, fracture patterns described, complications of treatment, and results summarized.

Data Synthesis:

Paucity of data and heterogeneity of studies limited statistical analysis. Data are presented as a review table with the key points summarized.

Conclusion:

In patella fracture, age >65 years and comminuted fracture pattern are predictors of increased fixation failure and postoperative stiffness, warranting special consideration. There is a trend toward improved functional outcomes when augmented fixation using mesh or plates is used in this group. Further level 1 studies are required to compare and validate new treatment options and compared them to standard surgical technique of tension band wire construct.

Novel Anterior Plating Technique for Patella Fracture Fixation

Patella fracture fixation remains a significant challenge for orthopedic surgeons. Although tension band fixation allows for reliable osseous union, especially in simple fracture patterns, it still presents several problems. Plate fixation of patella fractures is a method that allows for more rigid stabilization and earlier mobilization. At the authors' level 1 trauma center, one fellowship-trained trauma surgeon has transitioned to using a novel anterior, low-profile mesh plate construct for all types of patella fractures. This construct allows for stable fixation, osseous union, and neutralization of the inferior pole for even the most comminuted of patella fractures. [Orthopedics. 2017; 40(4):e739-e743.].

Superior Outcomes After Operative Fixation of Patella Fractures Using a Novel Plating Technique: A Prospective Cohort Study

OBJECTIVE

The purpose of this prospective cohort study was to determine if a new patella fracture fixation construct resulted in improved outcomes compared with traditional tension band techniques.

DESIGN

Comparative cohort study.

SETTING

Academic level I trauma center.

PATIENTS/PARTICIPANTS

Patients with isolated, unilateral patellar fractures were enrolled prospectively. From 2012 to 2014, 33 patients underwent fixation with a novel plate construct that spans half of the patella circumference laterally and provides multiplanar fixation through a low-profile plate. A comparison cohort was drawn from 25 patients treated from 2008 to 2012, where treatment consisted of traditional tension band fixation techniques.

INTERVENTION

Surgical fixation of patella fractures was performed with either a tension band or novel plate construct.

MAIN OUTCOME MEASUREMENTS

Subjective postoperative clinical outcomes and objective functional and strength measurements were subsequently collected.

RESULTS

The 2 cohorts had similar baseline characteristics. Patients with the plate construct had clinically and statistically significantly superior Knee Outcome Survey Activities of Daily Living Scale (KOS-ADLS) scores throughout the study period (P < 0.001). Functional testing also demonstrated significant improvements in patients with plate constructs compared with tension band constructs at 12 months. Patients in the plate cohort had significantly increased thigh circumferences (P = 0.003) and decreased anterior knee pain (P < 0.0001) compared with the tension band cohort.

CONCLUSIONS

In this prospective cohort study, the use of a novel fixation construct with multiplanar and interfragmentary fixation and minimal disruption of patellar vascularity enables improved clinical outcomes and functional performance.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Revisiting Tension Band Fixation for Difficult Patellar Fractures

Patella fractures with comminution, osteoporotic bone, and/or previously failed fixation are exceedingly difficult to reduce and fix. Moreover, the risk of symptomatic constructs and patients who are poorly compliant with postoperative activity restrictions can make these complex fracture patterns an even more challenging scenario. Although there is an array of techniques described for comminuted patella fractures, there lacks an accepted surgical technique for these difficult cases. In this clinical series, we describe an enhancement to the traditional tension band construct that uses additional wires and multiple tension bands to gather and fix comminuted fracture patterns in nontransverse planes, bolster osteoporotic bone, and secure fractures in patients undergoing a revision and/or have potential to be poorly compliant with postoperative activity restrictions. The clinical outcomes of 27 patients demonstrate high rates of bony union, functional range of motion, and low rates of both infection and failure. In conclusion, using the basic principles of tension band wiring remains highly versatile, useful, and economical in approaching difficult patella fractures.

The Use of Dual Reconstruction Plates for Failed Fixation of Patellar Fracture after Total Knee Replacement: A Case Report

Patellar fracture after total knee replacement (TKR) is one of the challenging problems in periprosthetic fracture. Open reduction with internal fixation (ORIF), as tension band wiring (TBW), usually required in cases with extensor mechanism disruption. However, many studies reported a high failure rate after using this technique. In this report, we presented an interesting case of periprosthetic patellar fracture after TKR with TBW failure that was successfully treated with double non-locking reconstruction plates fixation and TBW augmentation.

Low Profile Mesh Plating for Patella Fractures: Video of a Novel Surgical Technique

Patella fractures can be challenging to treat particularly in the presence of inferior pole comminution. In this video we present a novel surgical technique for the treatment of patella fractures using a small fragment low profile mesh plate. Key points are the surgical exposure with direct visualization of the articular reduction, the preparation of the mesh plate to accommodate patellar anatomy and the augmentation of the construct using Krackow sutures to address inferior pole comminution. Low profile mesh plating allows for multiplanar fixation of patella fractures while avoiding implant and fixation problems related to tension band fixation. Our early experience with this technique is encouraging and it appears that this technique is useful for the treatment of the majority of patella fractures.