Transarticular joint reconstruction and indirect plate osteosynthesis for complex distal supracondylar femoral fractures

Comparative study of retrograde intramedullary nailing versus locking extramedullary plating in complete articular fractures with metaphyseal comminution of the distal femur

INTRODUCTION

Fractures of the distal femur with metaphyseal comminution and complete intra-articular involvement (AO/OTA classifications 33C2 and 33C3) present challenges for reduction and fixation. However, an optimal fixation method remains unknown. This study aimed to compare the clinical and radiographic outcomes of locking extramedullary plating (LEP) and retrograde intramedullary nailing (RIN) for complete distal femoral intra-articular fractures with metaphyseal comminution.

MATERIALS AND METHODS

Between January 2016 and May 2022, 80 patients (45 men and 35 women; average age, 56.7 years) diagnosed with AO/OTA 33C2 and 33C3 were treated with either LEP or RIN and followed up for at least one year. Post-operative evaluations included radiographic assessments of bone union rate, timing, and alignment. Clinically, the knee joint range of motion (ROM), lower extremity functional scale (LEFS), and Kellgren and Lawrence (KL) grade were analyzed. The complications were also compared.

RESULTS

36 underwent LEP and 44 underwent RIN. Bone union was observed in 69.4% and 63.6% of the patients in the LEP and RIN groups, respectively (p = 0.64). The average union time was 6.9 months for the LEP group and 6.6 months for the RIN group (p = 0.51). A tendency toward varus deformity was observed in the RIN group, although the difference was not statistically significant. No significant differences were observed in knee ROM, LEFS, or KL grade. Complications included non-union (33.8%; RIN, 11; LEP, 16), varus deformity (5%; RIN, 4; LEP, 0), infection (1.3%; RIN, 0; LEP, 1), heterotrophic ossification (1.3%; RIN, 0; LEP, 1), and wound dehiscence (2.5%; RIN, 2; LEP, 0).

CONCLUSIONS

The surgical fixation methods, RIN and LEP, for complete distal femoral intra-articular fractures with metaphyseal comminution showed similar clinical and radiological outcomes. However, regardless of the type of fixation device used, there was a reduced rate of bone union owing to high energy and a less favorable prognosis.

Biomechanical evaluation of intramedullary retrograde nail and dynamic condylar screw used in unstable distal femoral fractures

Distal femur fractures are a common problem in orthopedics. Intramedullary retrograde nails (IRN) and dynamic condylar screws (DCS) are generally used for the treatment of these fractures. In this study, it was aimed to mechanically evaluate and compare these two implants used for the treatment of distal femur fractures. In this study, an AOOTA 33C1.3 fracture was created on the intact femur obtained from computed tomography images. The fractures were fixed with DCS and IRN. Then the created models were imported into the ANSYS Workbench for finite element analysis to determine the most convenient mechanical fixation type. The distal region of the femur was loaded considering 75 kg-f, and the created models were constrained in all directions from the femoral head. The intact femur was also analyzed to compare it with the DCS and IRN fixation models. The von Mises stress, strain, and displacement results were examined to determine the damage risk. According to the results, the risk of damage is lower in the model of fixation with IRN. The normal strain distribution in the model fixed with IRN is closer to the model of an intact femur. For this reason, the risk of stress shielding in IRN fixation is less than in DCS fixation. However, the fracture lines were more stable in the fixation with the DCS. In conclusion, fracture fixation with IRN is mechanically more suitable for distal femur fractures in terms of fracture healing.

Plating for Intra-articular Fractures of the Distal Femur: Functional and Radiological Outcomes

Background and objective Intra-articular fractures of the distal femur pose a significant surgical difficulty. These fractures are challenging to repair, and surgery is frequently advised for a successful outcome. The distal femoral fractures make up between 4-6% of all femoral fractures and account for less than 1% of all fractures. When compared to the single screw's axial stiffness or pullout resistance, as is the case with unlocked plates, the locking compression plate (LCP) is a single beam construct whose strength of fixation is equal to the sum of all screw-bone contacts. Against this backdrop, the current study was conducted for evaluating the functional outcomes of distal femoral fractures treated with LCP fixation. Methodology We conducted an observational study at a tertiary care facility in Kolar spanning a period of three years, from January 2019 to January 2022. We included all patients aged more than 18 years, who were diagnosed with distal femoral fractures [only those classified as type C according to the AO Foundation/Orthopedic Trauma Association (AO/OTA) classification]. Patients with terminal illnesses, revision of previous surgery, fractures with neurovascular injuries, and those diagnosed with pathological fractures were excluded from the study. The included patients were treated by LCP and discharged on postoperative day 10 after suture removal. The first follow-up was at the first month and subsequent follow-ups were done at three and six months, and the functional outcomes were assessed by using Neer's score for straight leg raises. Radiographs with fading fracture lines and callus formation on three-fourths of the cortices were regarded as indicators of fracture healing. Results Among the 30 study participants, 80% were males. The mean time for the radiological union was 15 weeks. In this study, there were no instances of infection or angular deformity greater than 5 degrees. About 80% of the study participants had ranges of motion (ROM) above 120 degrees at the end of the six-month follow-up period; 12 cases had an excellent score (40%), 15 cases (50%) had a satisfactory score, two cases (6.7%) had an unsatisfactory score, and only one case had poor score. Common complications observed were excessive bleeding, difficulty in reduction, superficial infections, and knee stiffness. Conclusion For patients with distal femoral fractures, the LCP treatment can result in good functional and radiological outcomes with fewer complications.

Surgical Tips and Tricks for Distal Femur Plating

Distal femur fractures are challenging fractures to treat, with nonunion rates as high as 22%. Precontoured locking plates have mitigated some earlier causes of failure, while introducing new challenges. The recognition of troublesome injury patterns and appropriate preoperative planning can avoid common pitfalls. Adjunctive techniques, including the use of a radiolucent triangle, an external fixator, unicortical plates, and crossing K-wires, can assist with fracture reduction and maintenance. It is important to understand the common pitfalls involved with distal femur plating and to consider a wide array of techniques to combat these challenges.

The Olerud Extensile Anterior Approach for Complex Distal Femoral Fractures: A Systematic Review

The management of AO/OTA (AO Foundation/Orthopaedic Trauma Association) 33-C3 complex distal femoral fractures presents challenges for orthopaedic surgeons. The extensile anterior approach may be an appropriate alternative treatment technique. The purpose of this systematic review is to (1) evaluate the Olerud approach (extensile anterior approach) for the treatment of 33-C3 complex distal femoral fractures and (2) evaluate postoperative patient outcomes. A systematic literature search was performed to retrieve studies that evaluated the treatment of 33-C3 complex distal femoral fractures. The PubMed database query resulted in 429 studies. Two reviewers independently reviewed the studies, of which six were identified. Patient demographics, AO/OTA fracture, surgical intervention, follow-up duration, clinical outcomes, and postoperative complications were collected and analyzed. The systematic review included six studies reporting on 85 patients (43 males and 42 females); the mean patient age was 45 years (range: 16-101 years). The most common cause of injury was road/traffic accident (51 patients). The mean follow-up time was 26 months (range: 3-72 months). In five studies, the mean time for union was 5.8 months (range: 2-9 months). The three most commonly reported complications were infection (seven [8.2%] patients), failure/malunion (three [3.5%] patients), and delayed tibial tuberosity osteotomy healing (three [3.5%] patients). Seventy (82.4%) patients did not suffer any postoperative complications. Out of 72 patients, 7 (9.7%) had resultant varus/valgus deformity. Overall, 57.1% had excellent/good functional outcomes. Based on the systematic literature review, the extensile anterior approach may be a viable alternative surgical option for 33-C3 complex distal femoral fractures. Given the current literature, more comprehensive and extensive studies need to be performed to ensure the best possible outcome.

Minimally invasive plate osteosynthesis: An update of practise

Since its conception in 1989, minimally invasive plate osteosynthesis (MIPO) has gained widespread popularity. It has been studied in over forty countries with most of the publications originating from Asia, Europe and North America. This review aims to describe the scientific path of MIPO from the very beginning to where it stands in current day times; study the pattern and contributing factors influencing its global spread. Finally, the up to date evidence is discussed with regard to several anatomical regions in which MIPO is mostly used. In the meantime, MIPO treads steadily towards accomplishing the same or better outcomes for more and more indications with the goal to leave a smaller surgical footprint to allow for undisturbed bone healing.

Minimally invasive plate osteosynthesis (MIPO) versus open reduction and internal fixation (ORIF) in the treatment of distal fibula Danis-Weber types B and C fractures

Background

Minimally invasive plate osteosynthesis (MIPO) has been reported to be superior to open reduction and internal fixation (ORIF) in the treatment of different long bone fractures. Nevertheless, in distal fibula fractures, the evidence of MIPO remains scarce. The aim of this retrospective study was to compare the clinical and radiological outcomes of the minimally invasive techniques applied to the distal fibula with open reduction and internal fixation within a 12 months follow-up.

Methods

A consecutive series of patients who underwent surgery using either ORIF or MIPO for the treatment of distal fibula fractures between 2010 and 2014 were retrospectively analyzed. All distal fibular fractures requiring an operative treatment (Danis-Weber type B ≙ AO type 44 B1, 2, 3 and Danis-Weber type C ≙ AO type 44 C1, 2) were included (ORIF n = 35, MIPO n = 35). Patients were assessed for postoperative pain using a visual analog scale (VAS) for pain (ranging from 0 to 10) and classified into 4 groups: “no pain” for VAS = 0, “low” for VAS = 1–3, “moderate” for VAS = 3–5, and “severe” for VAS = 5–10. In addition, complications of postoperative fracture-related infection, wound healing disorders, vascular and nerve injury and development of nonunion were evaluated and analyzed. Radiologic outcome measures assessing the talocrural angle, lateral and medial clear space, tibiofibular overlap, and talar tilt angle were evaluated postoperatively.

Results

The overall complication rate showed to be lower in the MIPO group compared to the ORIF group (14% vs. 37%, p = 0.029). Even though not statistically significant, specific surgery-related complications such as skin necrosis (3% vs. 9%, p = 0.275), nonunion (0% vs. 6%, p = 0.139), infections and wound healing disorders (9% vs. 20%, p = 0.141), as well as postoperative pain (17% vs. 26%, p = 0.5) were found more frequently in the ORIF group. The tibiofibular overlap demonstrated to be significantly lower in the ORIF group (3.3 mm vs. 2.7 mm, p = 0.033). The talocrural angle, talar tilt angle, and lateral and medial clear space showed to be equivalent in both groups.

Conclusion

In this retrospective single-center consecutive series, MIPO was superior to ORIF in the surgical treatment of distal fibula fractures with respect to the overall complication rate.

Trial registration

EKNZ Project-ID: 2019-02310, registered on the 20th of December 2019 with swissethics

Investigation of Biomechanical Characteristics of Orthopedic Implants for Tibial Plateau Fractures by Means of Deep Learning and Support Vector Machine Classification

An experimental comparative study of the biomechanical behavior of commonly used orthopedic implants for tibial plateau fractures was carried out. An artificial bone model Synbone1110 was used and a Schatzker V type tibial plateau fracture was created in vitro, then stabilized with three different implant types, classic L plate, Locking Plate System (PLS), and Hybrid External Fixator (HEF). The stiffness of the bone—implant assembly was assessed by means of mechanical testing using an automated testing machine. It was found that the classic L plate type internal implant has a significantly higher value of deformation then the other two implant types. In case of the other implant types, PLS had a better performance than HEF at low and medium values of the applied force. At high values of the applied forces, the difference between deformation values of the two types became gradually smaller. An Artificial Neural Network model was developed to predict the implant deformation as a function of the applied force and implant device type. To establish if a clear-cut distinction exists between mechanical performance of PLS and HEF, a Support Vector Machine classifier was employed. At high values of the applied force, the Support Vector Machine (SVM) classifier predicts that no statistically significant difference exists between the performance of PLS and HEF.

Transient retrograde interfragmentary compression technique in AO/OTA type 33-C distal femur fractures: A surgical technique and short-term radiographic follow up results

Surgical treatment of AO/OTA type 33-C fractures is a therapeutic challenge despite advances in surgical instruments and techniques. We introduce a novel surgical technique named transient retrograde interfragmentary compression (TRIC) to help intraarticular fragment reduction in AO/OTA type 33-C fracture. We inserted a partial threaded 7.0-cannulated screw with a washer along the transepicondylar axis from the medial femoral epicondyle during the articular block reduction process of AO/OTA type 33-C fractures to strengthen the compressive force between the condylar fragments and to enhance the handling of the articular block fragment in the alignmental correction stage. Following the provisional reduction and fixation using lateral distal femur locking compression plate, TRIC screw was removed. Fifteen AO/OTA type 33-C distal femoral intraarticular fractures of thirteen patients were surgically treated using the TRIC technique. We analyzed the radiographic result of the patients by measuring the horizontal gap and vertical step-off in the postoperative radiographs. Mean horizontal fracture gap was 0.34 mm and mean vertical step-off between bicondylar fragments was 0.63 mm. The median value of the horizontal fracture gap and vertical step off was 0 and 0.46 mm, respectively. Mean time to union in the bicondylar fracture fragment was 9 week. TRIC is considered to be a valuable surgical reduction technique in the treatment of the AO/OTA 33-C type fractures.

Minimally invasive plate osteosynthesis versus conventional open insertion techniques for osteosynthesis

Osteosynthesis has evolved theoretically and practically throughout its evolution. Similar to trends in other surgical fields, surgical techniques in fracture fixation, such as minimally invasive plate osteosynthesis (MIPO), have moved from large dissections to more tissue sparing methods. These plating techniques have been developed for a variety of bones, but more universal clinical adoption will rely upon improved clinical outcomes. The current review will describe minimally invasive techniques, evaluate their rationale, and summarize evidence for their efficacy.

Clinical effect of locking compression plate via posterolateral approach in the treatment of distal femoral fractures: a new approach

BACKGROUND

Distal femur fractures are difficult to manage, and the selection of implant approach for internal fixation remains controversial. This study explores the clinical outcome of treating distal femoral fractures with a locking compression plate using a posteriolateral novel approach.

METHODS

Twenty patients with distal femoral fractures were included in our study, and all patients underwent fixation of the fracture using a locking compression plate through a posterolateral approach. The postoperative fracture healing time, complications, and functional recovery were observed and recorded. The joint function was categorized according to the Kolmert functional criteria.

RESULTS

All patients were followed up for an average of 12 months, and all incisions healed by first intention. Among the all patients, 19 patients achieved fracture healing 3 to 4 months after surgery. The remaining 1 patient with distal femoral C3 comminuted fracture achieved partial fracture healing 15 months after surgery, and bone grafting was needed. All knees can reach the state of straightening, and the postoperative excellent rate was 90%. Among them, 8 patients had maximal flexion of more than 120°, 10 patients had flexion between 90° and 120°, and 2 other patients had flexion of 70° and 40°.

CONCLUSIONS

Fixation of the fracture using a locking compression plate through a posterolateral approach seemed to be an acceptable surgical option for treatment of distal femoral fractures.

Open Supracondylar-Intercondylar Fractures of the Femur Treatment With Taylor Spatial Frame

OBJECTIVES

To evaluate the Taylor spatial frame (TSF) for primary and definitive fixation of open supracondylar-intracondylar femoral (SIF) fractures.

DESIGN

Retrospective.

SETTING

Level I trauma center.

PATIENTS

Subset of 20 SIF open fractures treated with TSF extracted from a consecutive series of 80 SIF fractures treated between 2007 and 2013.

INTERVENTION

Eighteen (90%) fractures underwent definitive fixation with the TSF; 2 were treated primarily within 24 hours of injury. Mean time interval between primary treatment and secondary TSF was 5 days.

MAIN OUTCOME MEASUREMENTS

Clinical and radiological.

RESULTS

Complete union was obtained in 17 (85%) fractures without additional surgery at an average of 33 weeks. Three nonunions and 1 malunion occurred. No deep infection occurred. Results based on Association for the Study and Application of the Method of Ilizarov criteria: 37% excellent, and 63% good for bone outcomes; 5% excellent, 58% good, and 37% fair for functional outcomes. Neer knee scores were 21% excellent, 68% good, and 11% fair. The mechanical lateral distal femoral angle and anatomic posterior distal femoral angle values were within normal range in 80% and 90% of patients, respectively. Abnormal mechanical axis deviation was observed in 4 (20%) cases (2 had associated tibia fractures).

CONCLUSIONS

Primary and definitive fixation with the TSF are effective. Advantages include continuity of device until union, reduced risk of infection, early mobilization, restoration of primary defect caused by bone loss, easy and accurate application, convertibility and versatility, and improved union rate and range of motion for SIF open fractures.

LEVEL OF EVIDENCE

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

Use of Nonvascularized Autologous Fibular Strut Graft in the Treatment of Major Bone Defect after Periprosthetic Knee Fracture

We present the case of a patient who suffered a comminuted supracondylar periprosthetic femur fracture. The patient was an 86-year-old lady who suffered a minor fall at home and presented at our hospital with a right comminuted distal femur fracture around a total knee arthroplasty. The patient was submitted to a cruciate-sacrificing total knee replacement 6 years before at the same institution. Despite severe metaphyseal fragmentation and short distal fragment, the prosthesis was stable; thus, open fracture reduction and stabilization with internal fixation were performed. The surgical technique included the use of a nonvascularized autologous fibular strut graft as an augmentation technique in conjunction with double plating fixation. Clinically, patient presented a painless aligned knee 12 months after femur fixation, although she was not able to return to an independent level of activity. No pain involving the donor graft site was reported at the time of the most recent follow-up examination. This case study demonstrates the use of free nonvascularized autogenous fibular strut bone graft as an option to bridge major bone defects. This proved to be a relatively simple, not expensive procedure that can be done percutaneously and does not need high-quality training.

Are there too many screw holes in plates for fracture fixation?

Background

Implant breakage after the fixation of traumatic fractures is rare; however, when it occurs, it is debilitating for the patients and a challenge for surgeons. The purpose of this study was to analyze and identify the independent risk factors for implant breakage of traumatic fractures treated with plate osteosynthesis.

Methods

We reviewed the medical records of patients with a fracture to any part of their four extremities, clavicle, hand or foot, who underwent surgical plate osteosynthesis from January 2005 to January 2015, and who sustained a subsequent implant breakage. Kaplan–Meier univariate and multivariate Cox regressions were performed to identify independent associations of potential risk factors for implant breakage in this cohort.

Results

We identified 168 patients who underwent plate osteosynthesis surgery and had subsequent internal fixator breakage. The mean patient age was 40.63 ± 16.71 years (range, 3 to 78 years), with 72.0% (121) males and 28.0% (47) females. The average time between surgery and implant breakage was 12.85 ± 12.42 months (range, 1 to 60 months). In the final regression model, we show that inserting screws close to the fracture line is an independent predictive risk factor for implant breakage (HR, 2.165, 95%CI, 1.227 to 3.822; P = 0.008).

Conclusions

We found that inserting screws close to the fracture line is related to an increased risk of internal fixator breakage in patients treated with plate osteosynthesis after fracture. Plates with additional holes likely lead to an increased risk of implant breakage, presumably because surgeons cannot resist inserting extra screws into the holes adjacent to the fracture line, which reduces the stiffness of the plate. We have addressed this problem by designing a plate without holes adjacent to the fracture line.

Complex AO type C3 distal femur fractures: Results after fixation with a lateral locked plate using modified swashbuckler approach

BACKGROUND

Complex AO type C3 fractures of the distal femur are challenging injuries, fraught with complications such as malunion and stiffness. We prospectively evaluated a consecutive series of patients with complex AO type C3 distal femur fractures to determine the clinicoradiological outcome after fixation with a single locked plate using modified swashbuckler approach.

MATERIALS AND METHODS

12 patients with C3 type distal femur fractures treated with a lateral locked plate, using a modified swashbuckler approach, were included in the study. The extraarticular component was managed either by compression plating or bridge plating (transarticular approach and retrograde plate osteosynthesis) depending on the fracture pattern. Primary bone grafting was not done in any case. The clinical outcome at 1 year was determined using the Knee Society Score (KSS). The presence of any secondary osteoarthritis in the knee joint was noted at final followup.

RESULTS

All fractures united at a mean of 14.3 ± 4.7 weeks (range 6-26 weeks). There were no significant complications such as nonunion, deep infection, and implant failure. One of the patients underwent secondary bone grafting at 3 months. The mean range of motion of the knee was 120° ± 14.8° (range 105°-150°). Seven patients had excellent, three patients had good and two patients had a fair outcome according to the KSS at 1 year. At a mean followup of 17.6 months, three patients showed radiological evidence of secondary osteoarthritis of the knee joint. However, only one of these patients was symptomatic.

CONCLUSION

The results of complex C3 type distal femur fractures, fixed with a single lateral locked plate using a modified swashbuckler approach, are encouraging, with a majority of patients achieving good to excellent outcome at 1 year.

Tibial tubercle osteotomy to improve exposure in complex knee fractures: A cadaveric study and case series

Adequate exposure is fundamental to safely and correctly perform open procedures around the knee. Tibial tubercle osteotomy (TTO) has previously been described as a method to improve exposure, particularly in complex primary elective knee arthroplasty or revision surgery. We describe a tibial tubercle osteotomy technique to improve exposure in complex knee fractures and a cadaveric study and trauma case series.

METHODS

A cadaveric study using 8 knee specimens was conducted using a lateral subvastus approach to the knee. Standardised pictures were taken of the exposure, the tibial tubercle osteotomy was performed and pictures were taken of the new exposed area. These images were compared using a computer program that calculated the area of exposure before and after tibial tubercle osteotomy and the results analysed. The technique was then used in a case series of 6 different complex knee fractures including three distal femoral, one periprosthetic distal femur and two tibial plateau fractures. The outcomes of these patients were followed clinically and radiologically.

RESULTS

All specimens in the cadaveric study demonstrated an increase in area of exposure after the TTO with a mean increase of 148%. All tibial tubercle osteotomies performed in the trauma case series were united by 6 months without complication.

CONCLUSIONS

Tibial tubercle osteotomy is a recognised technique for improving exposure to the knee. This has been demonstrated in a cadaveric study and in a case series of six complex fractures around the knee. If performed properly, this technique can be extended to appropriate trauma cases with good results.

Fixator-assisted Technique Enables Less Invasive Plate Osteosynthesis in Medial Opening-wedge High Tibial Osteotomy: A Novel Technique

BACKGROUND

Opening-wedge high tibial osteotomy is a well-established procedure in the management of medial osteoarthritis of the knee and correction of proximal tibia vara. Recently, surgical approaches using less invasive plate osteosynthesis have been used with the goal of minimizing complications from more extensive soft tissue exposures. However, to our knowledge, less invasive fixator-assisted plate osteosynthesis has not been tested in the setting of opening-wedge high tibial osteotomy.

QUESTIONS/PURPOSES

The purposes of this study were (1) to assess the complications associated with use of a fixator-assisted less invasive plate osteosynthesis technique to stabilize an opening-wedge high tibial osteotomy in the treatment of proximal tibial vara; and (2) to evaluate the ability of this technique to achieve correction of the proximal tibial deformity and achieve osseous union.

METHODS

From June 2011 to June 2013, a total of 157 limbs in 83 patients who underwent fixator-assisted high tibial osteotomy for (1) idiopathic genu vara; or (2) osteoarthritis of the knee with proximal tibia vara were initially enrolled. Of these, eight limbs (5%) were excluded on the way; thus, 149 limbs in 77 patients were evaluated. During the period in question, no other techniques were used for proximal tibial osteotomy. The surgical procedures included less preparation of soft tissue, proximal tibial osteotomy, application of a temporary external fixator, correction of alignment, and final fixation with the help of an external fixator. Complications were assessed by chart review and the alignment in both coronal and sagittal planes was compared pre- and postoperatively. Radiographic review to confirm osseous union and alignment was performed by two of the authors not involved in clinical care of the patient. Delayed union was described as union occurring later than 4 months.

RESULTS

Thirty limbs out of 149 tibiae (20%) showed complications, all of which were resolved without leaving any sequela. Twenty-seven limbs out of 149 limbs (18%) showed lateral cortical hinge fracture and three limbs out of 149 limbs (2%) showed soft tissue complications (two superficial infections, one wound hematoma). The overall completeness of reaching the target correction was excellent. In the coronal plane, the difference between the amount of real correction and the amount of target correction was 0.3° ± 0.7° (p < 0.001). In the sagittal plane, the difference between pre- and postoperative posterior proximal tibial angle was -0.1° ± 0.2° (p < 0.001). All osteotomies healed before 4 months.

CONCLUSIONS

Fixator-assisted high tibial osteotomy is a valid option for medial opening-wedge high tibial osteotomy, which enables less invasive surgery with excellent coronal/sagittal/rotational alignment control. However, future studies should compare this approach with other approaches for proximal tibial osteotomy to ascertain whether indeed this procedure is less invasive or more reliable.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Treatment of distal femur fractures in a regional Australian hospital

AIM: To review our outcomes and compare the results of the Less Invasive Stabilization System (LISS) to other implants for distal femur fracture management at a regional Australian hospital.

METHODS: The LISS is a novel implant for the management of distal femur fractures. It is, however, technically demanding and treatment results have not yet been assessed outside tertiary centres. Twenty-seven patients with 28 distal femur fractures who had been managed surgically at the Mackay Base Hospital from January 2004 to December 2010 were retrospectively enrolled and assessed clinically and radiologically. Outcomes were union, pain, Lysholm score, knee range of motion, and complication rates.

RESULTS: Twenty fractures were managed with the LISS and eight fractures were managed with alternative implants. Analysis of the surgical techniques revealed that 11 fractures managed with the LISS were performed according to the recommended principles (LISS-R) and 9 were not (LISS-N). Union occurred in 67.9% of fractures overall: 9/11 (82%) in the LISS-R group vs 5/9 (56%) in the LISS-N group and 5/8 (62.5%) in the alternative implant group. There was no statistically significant difference between pain, Lysholm score, and complication rates between the groups. However, there was a trend towards the LISS-R group having superior outcomes which were clinically significant. There was a statistically significant greater range of median knee flexion in the LISS-R group with compared to the LISS-N group (P = 0.0143) and compared with the alternative implant group (P = 0.0454).

CONCLUSION: The trends towards the benefits of the LISS procedure when correctly applied would suggest that not only should the LISS procedure be performed for distal femur fractures, but the correct principle of insertion is important in improving the patient’s outcome.

Locking Compression Plate in Distal Femoral Intra-Articular Fractures: Our Experience

Background. Intra-articular fractures of distal femur present a huge surgical challenge. The aim of this study is to evaluate functional outcome, fracture healing, and the complications of distal femoral intra-articular fractures using locking compression plates. Material and Methods. We reviewed 46 distal femoral fractures treated with distal femoral locking compression plates between 2009 to 2012. There were 36 men and 10 women with mean age of 35 years (range 20–72). More than half of the patients were of type C3 (AO classification) and had been caused by high energy trauma with associated injuries. Results. 2 patients were lost to follow-up. Of the remaining 44 patients, the mean follow-up period was 25 months (range 18–36). The mean time for radiological union was 12 weeks (range 10–18) except 2 patients which had gone for nonunion. At the latest follow up ROM >120° is noted in 32 patients, 90–120 in 10 patients, and 70–90 in 2 patients. 38 patients (86%) had good/excellent outcome. Conclusion. Use of standard lateral approach for simple intra-articular distal femoral fractures (C1) and transarticular/minimally invasive techniques for complex intra-articular fractures (C2/C3) results in improved exposure of the knee joint and better union rates with low incidence of bone grafting.

Patella osteotomy: a new approach for complex trauma around the knee

Complex floating knee injuries, comprising complete articular distal femur and proximal tibia fractures, are a significant challenge in Orthopedic Traumatology. Traditional surgical approaches can result in a limited exposure, compromising osteosynthesis, with an extensive soft tissue dissection predisposing to adhesion of the quadriceps and arthrofibrosis. The Patella Osteotomy technique provides unrivaled visualization of the articular surfaces of the knee, with a limited soft tissue dissection to permit the anatomical reconstruction of the articular injury, while minimizing the risk of postsurgical complications and reducing intraoperative fluoroscopy time.

Mismatch of anatomically pre-shaped locking plate on Asian femurs could lead to malalignment in the minimally invasive plating of distal femoral fractures: a cadaveric study

BACKGROUND

LCP-DF (locking compression plate-distal femur) has been introduced as an anatomically pre-shaped plate that does not require further contouring. However, the LCP-DF was developed based on skeletal measurements in Caucasians. It is unknown whether the LCP-DF fits Asians.

OBJECTIVE

The purpose of this study was to assess the conformity of the LCP-DF in Asian adult femurs and also to determine the matching pattern of this anatomically pre-shaped LCP-DF in normal Asian adult femurs and the clinical implications of the matching pattern.

METHODS

Sixty adult cadaver femurs were obtained from 41 male and 19 female cadavers with an average age of 63 years (31-95). An 11-hole LCP-DF was applied to the lateral surface of the distal femur according to the contour. Any mismatches between the bone and the plate were recorded. Then the distance from the inner surface of the plate to the cortex was measured at the sites of mismatch. C-arm AP image of the distal femur was taken and the angle between the distal most locking screw and the joint line was measured, and it was named as joint screw angle (JSA).

RESULTS

Mismatch was found at the level of proximal 4-5 holes of the plate with an average distance of 11.36 mm (range 0-32 mm) at the tip of the plate. Otherwise, the overall conformity of the LCP-DF was good. The average JSA was 2.15 ± 1.78° (ranged from 0° to 5°).

CONCLUSION

A rather consistent pattern of mismatch was found at the proximal part of the 11-hole LCP-DF. An attempt to fit the plate to the bone at this level may cause valgus malalignment at the fracture site.

Pitfalls in the application of distal femur plates for fractures

Despite design features intended to aid the surgeon in restoring proper alignment, malunion and implant-related problems are relatively common after a distal femur fracture treated with plate fixation. This article presents case examples of these problems followed by a discussion of the relevant distal femoral anatomy, design features of modern locked distal femur plating systems, and technical points necessary to avoid malunion and implant-related problems when using these devices.

Robot-assisted fracture reduction using three-dimensional intraoperative fracture visualization: an experimental study on human cadaver femora

Closed fracture reduction can be a challenging task. Robot-assisted reduction of the femur is a newly developed technique that could minimize potential complications and pitfalls associated with fracture reduction and fixation. We conducted an experimental study using 11 human cadaver femora with intact soft tissues. We compared robot-assisted fracture reduction using 3D visualization with manual reduction, using 2D fluoroscopy. The main outcome measure was the accuracy of reduction. The manual reductions were done by an experienced orthopedic trauma surgeon, whereas the robot-assisted reductions were done by surgeons of different experience. The robot-assisted group showed significantly less postreduction malalignment (p < 0.05) for internal/external rotation (2.9 degrees vs. 8.4 degrees ) and for varus/valgus alignment (1.1 degrees vs. 2.5 degrees ). However, the reduction time was significantly (p < 0.01) longer (6:14 min vs. 2:16 min). The higher precision associated with robot-assisted fracture reduction makes this technique attractive and further research and development worthwhile. In particular, less experienced surgeons may benefit from this new technique.

Less invasive percutaneous wave plating of simple femur shaft fractures: A prospective series

In developing nations, fixation of femoral shaft fractures with intramedullary (IM) nails can pose significant challenges. Use of IM implants is commonly limited by availability, funds or patient's physique. Conversely, traditional compression plates are usually readily available at a much lower cost, making bridge plating of femur fractures a frequently used surgical technique. We hypothesised that less invasive percutaneous plate osteosynthesis (MIPPO) of femoral shaft fractures has a similar outcome compared to IM nailing. The study is designed as a prospective case series at a Level 1 university trauma centre. Fifty-seven patients with simple femur shaft fractures (Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association (AO/OTA) type A) were enrolled between April 2001 and December 2005 and followed up for a minimum of 1 year or until fracture union. Primary outcome measures included union rate and time to union. Secondary outcome parameters were hardware failure, malalignment, infection and need for revision surgery. The mean age of the study cohort was 24.7 years. Fifty-four patients sustained associated systems injury. Primary union occurred in 54 patients in an average time of 13 weeks. Two patients presented with implant failure, and one patient displayed signs of delayed union. Six patients developed valgus deformities, whereas five patients displayed external rotation malalignment. One patient developed a superficial wound infection, and another presented with a deep infection. Bridge wave plating represents a safe and efficacious treatment alternative to IM nailing for simple femoral shaft fractures in countries where IM nails are limited by availability, costs and patient's physical characteristics.

Condylar buttress plate versus fixed angle condylar blade plate versus dynamic condylar screw for supracondylar intra-articular distal femoral fractures

PURPOSE

To compare outcomes of 3 fixation techniques for intra-articular distal femoral fractures.

METHODS

Records of 59 men and 49 women aged 16 to 80 (mean, 47) years who underwent internal fixation for 116 type-C (complete intra-articular) distal femoral fractures were retrospectively reviewed. According to the AO classification, 25 fractures were type C1 (23 closed and 2 open), 71 type C2 (69 closed and 2 open), and 20 type C3 (16 closed and 4 open). Based on implant availability at the time, all surgeries were performed by a single surgeon using a condylar buttress plate (n=38), a fixed angle (95 degrees) condylar blade plate (n=24), or a dynamic condylar screw (n=54). The mean follow-up period was 11 (range, 4-19) years. At the latest follow-up, functional outcome was classified according to Schatzker and Lambert criteria.

RESULTS

Functional outcomes were excellent in 64 (55%) of the fractures, good in 37 (32%), moderate in 9 (8%), and poor in 6 (5%). Outcomes in patients treated by the dynamic condylar screw were significantly superior to those treated by the condylar buttress plate (p=0.016) or condylar blade plate (p=0.001). Good-to-excellent results were achieved in 96% vs 84% vs 71% of these patients, respectively. Complication rates were lower in the dynamic condylar screw group than the other 2 groups (pseudarthrosis, 5% vs 11% vs 25%; varus deformity, 4% vs 26% vs 25%; knee stiffness, 0% vs 5% vs 8%, respectively). No implant failure was encountered.

CONCLUSION

Dynamic condylar screw fixation for distal femoral fractures achieves better functional outcomes and lower complication rates.

Treatment of distal femoral fracture by minimally invasive percutaneous plate osteosynthesis: comparison between the dynamic condylar screw and the less invasive stabilization system

BACKGROUND

Treatment of distal femoral fractures by percutaneous plating without direct manipulation of the fracture fragments leads to good clinical outcome. Percutaneous plating has traditionally involved using a dynamic condylar screw (DCS) and the less invasive stabilization system (LISS) was reported. The biomechanical study showed that the LISS had the enhanced ability to withstand higher loads. However, there were no clinical comparison study of distal femoral fractures treated with DCS and LISS. The aim of this study was to outline any differences in clinical and radiological results between the DCS and the LISS for treating distal femoral fractures.

METHODS

Forty-five supracondylar or intercondylar femoral fractures were treated by minimally invasive percutaneous plating with the DCS or the LISS without bone graft. There were 26 patients with 26 fractures in the DCS group and 19 patients with 19 fractures in the LISS group. The data of the clinical and radiographic outcomes were compared between the two different fixation devices.

RESULTS

Complete union was achieved in 41 of the 45 patients (91.1%). The success rate was 96.2% in the DCS group and 94.7% in the LISS group (p = 0.672). The mean fusion time was 19.18 weeks in the DCS group and 19.38 weeks in the LISS group (p = 0.835). The average range of motion of the knee joint was 111.65 degrees in the DCS group and 116.26 degrees in the LISS group (p = 0.334). Early implant failure only occurred in the DCS group (11.5%, p = 0.252, odds ratio = 1.826 [95% CI: 1.387-2.404]). The total complication rate was 15.4% in the DCS group and 15.8% in the LISS group (p = 0.641). The mean loss of coronal fracture fragment angle was -0.77 degrees in the DCS group and -0.19 degrees in the LISS group (p = 0.125).

CONCLUSION

Minimally invasive percutaneous plating with the DCS or the LISS provides good outcome with few complications in the treatment of distal femoral fractures. Both systems minimize soft tissue trauma. LISS seems to have lower risk of early implant loosening than the DCS.

The condylar plate for treatment of distal femoral fractures: a long-term follow-up study

The aim of this retrospective study was to present the long-term functional and radiological outcomes of indirect reduction techniques and fixation with a condylar plate for treatment of distal femoral supracondylar or intracondylar femoral fractures. The series included 24 men and 17 women, mean age 51 years, between March 1994 and April 1999. All fractures were AO type 33, and eight were open fractures. Primary iliac bone graft was used in five cases. In one case of severe osteoporosis, screw fixation was augmented with cement. There were three delayed unions, one non-union and two infections; four participants required reoperation with bone grafts. Two (5%) participants developed a second varus deformity and three a second valgus deformity; correction osteotomy with bone grafts was necessary in these cases. After a mean follow-up of 9.5 years, the mean Neer score was 82 points and indicated that function was excellent in 16, satisfactory in 9, unsatisfactory in 4 and poor in 2 cases. The mean Neer score in cases of isolated fracture was 89 points and in cases with additional injuries was 72 points. Thus the long-term results of indirect reduction techniques of distal femoral fractures treated with the condylar plate were good to excellent in 82% of cases.

Distal Tibial Fracture Fixation with Locking Compression Plate (LCP) Using the Minimally Invasive Percutaneous Osteosynthesis (MIPO) Technique

BACKGROUND

Treatment of distal tibial fractures has always been a challenge. Distal tibia is more superficial, with less soft tissue coverage and blood supply. Therefore, operative treatment can lead to complications. We aim to see the results of the distal tibial fracture fixation with LCP using MIPO.

PATIENTS AND METHODS

Twenty-one consecutive patients were prospectively reviewed. AO types 43A, 43B and 43C were included. Fourteen male and seven female patients with a mean age of 51 years were included.

RESULTS

Mean time to union was 5.5 months (range 3-13 months). Seventeen fractures healed with good functional outcome. One patient had delayed union. One patient had nonunion and underwent revision; the fracture ultimately healed with good functional outcome. Two patients developed superficial wound infections but the fractures united completely.

DISCUSSION

The MIPO technique for distal tibia has shown good results with many additional advantages over the conventional methods. Early mobilization without risk of secondary displacement helps to prevent stiffness and contracture.

Long-term functional outcomes after intra-articular distal femur fractures: ORIF versus retrograde intramedullary nailing

This retrospective study evaluated the long-term clinical, functional, and radiographic outcomes of traditional open reduction internal fixation (ORIF) versus limited open reduction with retrograde intramedullary nailing for supracondylar-intercondylar distal femur fractures (Arbeitsgemeinschaft für Osteosynthesefragen [AO] 33-C type). Twenty-three fractures were followed in 22 patients for a mean follow-up of 80 months. The rate of subsequent bone-grafting procedures (67% vs 9%) and malunion (42% vs 0%) were significantly higher in ORIF compared to the less invasive retrograde intramedullary nailing treatment. A nonsignificant trend was noted for increased infection (25% vs 0%) and nonunion (33% vs 9%) in the ORIF group. The physical function component of the SF-36 was approximately 2 standard deviations below the US population mean, and 50% of patients demonstrated radiographic changes of posttraumatic arthritis. No patient has had a subsequent total knee arthroplasty.

Minimally invasive plate osteosynthesis (MIPO) in the treatment of the femoral shaft fracture where intramedullary nailing is not indicated

The aim of this study was to examine the results of minimally invasive plate osteosynthesis (MIPO) of the femoral shaft fracture in patients where intramedullary nailing is contraindicated and evaluate the proper number of the screws for stable fixation. This was a retrospective study of 36 closed femoral shaft fractures which underwent MIPO using a conventional 4.5 broad dynamic compression plate (DCP) with 14-18 holes fixed with three or four screws in the proximal and distal fragments. Thirty-three fractures had bony union in 21.0 weeks (range, 12-28 weeks), two had delayed union that required bone graft and union at 28 and 32 weeks. Malalignment occurred in five cases. Sixty-two fragments were fixed with three screws--40 in cluster and 22 in separated positions. Ten fragments were fixed with four screws--eight in cluster and two separated. Broken screws were found in three cases; all were in the group with three screws fixed in cluster group. MIPO of the femoral shaft fracture is an alternative treatment in the patient where intramedullary nailing is contraindicated. Malalignment is the common complication that must be carefully evaluated intraoperatively. We recommend using at least three separated screws in each fragment to reduce the risk of screw breakage.

Treatment of acute distal femur fractures

An emphasis on indirect reduction techniques to restore limb alignment has improved the rate of fracture healing and decreased infection rates, fixation failure, and the need for bone grafting.

Patient-specific three-dimensional composite bone models for teaching and operation planning

BACKGROUND

Orthopedic trauma care relies on two-dimensional radiograms both before and during the operation. Understanding the three-dimensional nature of complex fractures on plain radiograms is challenging. Modern fluoroscopes can acquire three-dimensional volume datasets even during an operation, but the device limitations constrain the acquired volume to a cube of only 12-cm edge. However, viewing the surrounding intact structures is important to comprehend the fracture in its context. We suggest merging a fluoroscope's volume scan into a generic bone model to form a composite full-length 3D bone model.

METHODS

Materials consisted of one cadaver bone and 20 three-dimensional surface models of human femora. Radiograms and computed tomography scans were taken before and after applying a controlled fracture to the bone. A 3D scan of the fracture was acquired using a mobile fluoroscope (Siemens Siremobil). The fracture was fitted into the generic bone models by rigid registration using a modified least-squares algorithm. Registration precision was determined and a clinical appraisal of the composite models obtained.

RESULTS

Twenty composite bone models were generated. Average registration precision was 2.0 mm (range 1.6 to 2.6). Average processing time on a laptop computer was 35 s (range 20 to 55). Comparing synthesized radiograms with the actual radiograms of the fractured bone yielded clinically satisfactory results.

CONCLUSION

A three-dimensional full-length representation of a fractured bone can reliably be synthesized from a short scan of the patient's fracture and a generic bone model. This patient-specific model can subsequently be used for teaching, surgical operation planning, and intraoperative visualization purposes.

Successful results of minimally invasive surgery for comminuted supracondylar femoral fractures with LISS: comparative study of multiply injured and isolated femoral fractures

BACKGROUND

The aim of this prospective study was to compare the outcomes of distal femoral fractures treated by the Less Invasive Stabilization System (LISS) in multiply injured and isolated fracture cases.

METHODS

This study comprised 26 patients (16 men, 10 women), who had 27 distal femoral fractures. Patients were divided into two groups; multiple injuries (group I) or isolated distal femoral fracture (group II). The average Injury Severity Score of group I was 26.7. Operations were performed according to biological fixation principles in a submuscular manner. No bone grafting was performed to enhance the healing. The cases were evaluated based on the criteria of Schatzker-Lambert and the modified Hospital for Special Surgery (HSS) scoring system.

RESULTS

The mean follow-up period was 25.8 months. Union was achieved in all cases. Two patients in group I required débridement procedures due to deep infection. One of them healed completely but the other did not. The average range of knee motion of groups I and II at the last control were 112.8 degrees and 121.8 degrees , respectively. The mean modified HSS scores were 73.9 and 79.9, respectively. There was no significant difference in the HSS scores or the range of knee motion. The time to full weight bearing was longer in group I owing to the concomitant injuries.

CONCLUSIONS

We concluded that LISS is a useful method for comminuted supracondylar fractures with multiple trauma patients as the results showed no significant differences when compared with those of patients with isolated femoral fractures.

Management of periprosthetic femur fractures with a first generation locking plate

Periprosthetic femoral fractures associated with well-fixed total hip or total knee prostheses present a challenging management problem as these injuries typically occur in osteoporotic bone. Conventional management entails extensive periosteal stripping to allow for plate fixation. We reviewed a consecutive series of patients who sustained fractures associated with a well fixed total knee prosthesis, a total hip prosthesis, or both. Twenty four patients with a mean age of 69.4 years were included. All patients underwent fixation via percutaneous insertion techniques with a first generation locking plate and screws (LISS--Less Invasive Skeletal Stabilization, Synthes, Paoli, PA). Three patients sustained fractures distal to a well-fixed total hip prosthesis, eighteen fractures occurred above a well-fixed total knee femoral component, and three were interprosthetic. The mean length of time from the index procedure to fracture was 76 months, range (2-172 months). Blood loss was minimal in each case, with a mean operative time of 90 min (range 60-120 min). Twenty one of twenty four went on to unite at a mean 6.2 months (range 3-19 months). Three patients underwent further surgery. One failure of fixation was encountered. Percutaneous fixation is technically demanding as it requires stable fixation without direct visualisation of the fracture site or the entire fixation device. Our results suggest percutaneous fixation with the LISS plate is an effective although technically demanding method of treatment. Complication rates were comparable to existing reports of this treatment method, and appear to be improved over traditional methods of fixation.

Effect of mechanical stability on fracture healing--an update

The effects of mechanical stability and mechanical stimulation have been studied extensively in vivo using a variety of animal models and stimulators. Early results indicated that stimulation does not significantly contribute to fracture healing. Lately, however, more rigid external stimulators that withstand increased callus formation have identified a contribution of mechanical stimulation in the initial period of fracture healing. However, these studies also show that the same amount of movement inhibits union during the last phase of fracture healing. On the cellular level, most investigations have used 2-dimensional cell culture systems to study the response of different cell phenotypes to mechanical stimulation, shear stress, and hydrostatic pressure. Cell proliferation and differentiation are clearly altered by these stimuli, however, the response depends on the cell type, the magnitude of the strain, and the cofactors applied. Lately, 3-dimensional cell cultures in mechano-bioreactors have been used to investigate the response of bone marrow stromal cells. These results indicate that the predominant stimulus for proliferation is perfusion. Mechanical stimulation affects cell differentiation and depends on the strain magnitude and the cell phenotype. As a consequence, today's implants should be applied in a fashion that supports maximum perfusion at the fracture site. In the early period, the osteosynthesis should facilitate micromotion of the fragments if secondary fracture healing is desired. At the same time, joint congruency, and axial and rotational positions have to be maintained. In the final period of healing, motion within the calcifying callus should be limited, which is naturally achieved by the increasing stiffness of the callus ossification.

Femoral biologic plate fixation

New techniques of fracture fixation such as indirect reduction, careful soft tissue handling, and elastic fixation are being used in place of older methods of mechanical stabilization. These new techniques led to the concept of biologic plate fixation. We systematically reviewed the literature and provide an overall evaluation of femoral biologic fixation for fracture treatment. We analyzed 19 studies with 687 patients with 697 femoral fractures. Twenty-three percent of the fractures were subtrochanteric, 29% were diaphyseal, and 48% were supracondylar. Twenty-two percent were open fractures. The majority (81%) were comminuted and AO Types B and C. The overall union rate was 98.4%, with a mean time to union ranging from 10.7 to 24 weeks. Primary or secondary bone-grafting procedures were reported in all but one study with a frequency ranging from 0-55%. The most frequently recorded complications were malunion (0-29%) and reoperation (0-23%). The high union rate, low infection rate (2%), and occasional need for bone graft indicate biologic plate fixation is a viable alternative to modern nailing techniques, particularly in patients with polytrauma.

LEVEL OF EVIDENCE

Therapeutic study, Level III.

Low complication rate of LISS for femur fractures adjacent to stable hip or knee arthroplasty

Fractures of the femur after a knee or hip arthroplasty historically have been plagued with high complication rates. The Less Invasive Stabilization System (LISS) has theoretical advantages of improved biomechanics and limited insult to the bone's vascular supply. We theorized that the LISS would have a lower complication rate than historical controls for these fractures. Patients who were treated with a LISS at two Level I trauma centers from July 2001 to July 2003 were prospectively followed up. The inclusion criteria were an acute fracture of the femur treated with a LISS in a patient with a stable ipsilateral total knee prosthesis and/or hip pros- thesis. There were 24 patients in the study group. The injury mechanism was a low-energy fall for all patients. All patients were females with an average age of 79.5 years (range. 64-93 years). Ten patients had ipsilateral hip arthroplasties, nine patients had ipsilateral total knee arthroplasties, and five patients had knee and hip arthroplasties. Followup was at an average of 48 weeks (range, 17-101 weeks). Eighteen of the 19 fractures in the surviving patients with followup healed uneventfully for a complication rate of 5.2%. One fracture was complicated by hardware pullout and was revised to a longer LISS that healed uneventfully. We think our data show that our patients had a low complication rate compared with that of historical controls, and we suggest that the LISS may be an appropriate treatment alternative for femur fractures associated with stable hip or knee prostheses.

LEVEL OF EVIDENCE

Therapeutic, Level IV.

Percutaneous plating of lower limb long bone fractures

We conducted a study on indirect reduction and percutaneous plating in the treatment of 22 cases (mean age 50.3, S.D. 18.5, range 18-88) of non-diaphyseal fractures of long bones of the lower limb mainly using the lateral tibial head buttress plate. All cases achieved radiological union and full weight bearing walking. No major malalignment resulted and only one Gustilo III-b compound fracture required bone grafting. None required revision surgery from problem with union. One case required revision in the early learning phase and another patient suffered wound complication from self-herbal application which required local flap surgery. The satisfactory functional results and the lack of soft tissue complications suggest that this method should be considered in metaphyseal fractures where intramedullary nails are not applicable.

Biomechanical Evaluation of the Less Invasive Stabilization System and the 95-degree Angled Blade Plate for the Internal Fixation of Distal Femur Fractures in Human Cadaveric Bones with High Bone Mineral Density

BACKGROUND

The less invasive stabilization system (LISS) is an internal fixator that utilizes unicortical locked screws for fixation of distal femur fractures. A question is whether locked unicortical screw fixation is sufficient, when compared with a standard implant such as a blade plate.

METHODS

Eight matched pairs of fresh-frozen cadaveric femora were instrumented with either the LISS or a 95-degree blade plate. A 4-cm supracondylar gap fracture model was created and all bone-implant constructs were tested to failure in axial loading.

RESULTS

All constructs failed by plastic deformation of the implant. There was no significant difference between the LISS and the blade plate constructs with respect to load to failure.

CONCLUSIONS

Despite unicortical fixation axial loading to failure of the LISS did not result in implant/screw pull-out neither proximally nor distally. However, there does not appear to be a biomechanical advantage of using the LISS as opposed to a blade plate in bones with high bone mineral density.

Distal femoral fractures: a review of fixation methods

The treatment of distal femoral fractures has evolved; nevertheless, these fractures remain difficult to treat and carry an unpredictable prognosis. Over the years, many different strategies have been used with varying success. This review outlines the problems presented by distal femoral fractures and the results of current surgical techniques.

Fractures of the distal tibia treated with closed reduction and minimally invasive plating

INTRODUCTION

The treatment of fractures of the distal tibia can be problematical because of the thin soft-tissue covering. Bridging slide-insertion plate osteosynthesis is performed by indirect, axially correct reduction of the fracture and stabilization without opening the soft tissue at the fracture site. Stripping of the periosteum is thus avoided, the fragments remain integrated into the soft tissue, and healing occurs spontaneously by way of callus formation.

MATERIALS AND METHODS

Seventy-one patients treated by slide-insertion plate osteosynthesis were followed up over at least 2 years. As would be expected in this anatomical region, the proportion of C fractures and fractures with concomitant soft-tissue damage was high. The majority of patients were treated by application of an external fixator on the day of the accident; the definitive osteosynthesis with the slide-insertion plate was performed at a later date after healing of the soft tissues.

RESULTS

In 68 patients, fracture healing was achieved within 2 years. In 80% of the cases, the final X-ray follow-up showed no or tolerable axis deviations (<5 degrees) in the varus/valgus plane or in the recurvation/antecurvation plane. A deviation >10 degrees requiring a correcting osteotomy was found in only 1 patient. Postoperative complications were rare occurrences. Five patients required an additional cancellous bone graft to deal with inadequate bone healing. System-related complications (instability, malalignment) due to intraoperative technical errors only had to be corrected in revision operations in 2 patients.

CONCLUSION

Closed reduction and minimally invasive plating offers the combined advantages of minimal soft-tissue damage with stable fracture fixation.

Minimally invasive percutaneous plating of distal femoral fractures using the dynamic condylar screw

BACKGROUND

In distal femoral fractures, conventional open reduction and internal fixation causes complications because of excessive soft-tissue stripping. To prevent this, minimally invasive percutaneous plating was performed in distal femoral fractures.

METHODS

Sixteen supracondylar or intercondylar femoral fractures were treated by minimally invasive percutaneous plating with the dynamic condylar screw without bone graft. Five (31%) were open fractures.

RESULTS

All fractures healed except one. The average time for fracture healing was 17 weeks (range, 14-22 weeks). Complications included one nonunion related to early full weight bearing. No patient showed malunion or deep infection. Results were evaluated by modified Neer rating, and all patients had excellent or good results. Intra-articular fractures showed less favorable range of motion and clinical scores than extra-articular fractures.

CONCLUSION

Minimally invasive percutaneous plating with the dynamic condylar screw can provide favorable results in the treatment of distal femoral fractures.

Treatment of distal femur fractures using the less invasive stabilization system: surgical experience and early clinical results in 103 fractures

OBJECTIVE

To summarize the complications and early clinical results of 123 distal femur fractures treated with the Less Invasive Stabilization System (LISS; Synthes, Paoli, PA).

DESIGN

Retrospective analysis of prospectively enrolled patients.

SETTING

Two academic level I trauma centers.

SUBJECTS AND PARTICIPANTS

One hundred nineteen consecutive patients with 123 distal femur fractures (OTA type 33 and distal type 32 fractures) treated by 3 surgeons. One hundred three fractures (68 closed fractures and 35 open fractures) in 99 patients were followed up at least until union (mean follow-up = 14 months, range: 3-50 months).

INTERVENTION

Surgical reduction and fixation of distal femur fractures.

MAIN OUTCOME MEASUREMENTS

Perioperative complications, radiographic union, infection rate, loss of fixation, alignment, and range of motion.

RESULTS

Ninety-six (93%) of 103 fractures healed without bone grafting. All fractures eventually healed with secondary procedures, including bone grafting (1 of 68 closed fractures and 6 of 35 open fractures). There were 5 losses of proximal fixation, 2 nonunions, and 3 acute infections. No cases of varus collapse or screw loosening in the distal femoral fragment were observed. Malreductions of the femoral fracture were seen in 6 fractures (6%). The mean range of knee motion was 1 degrees to 109 degrees .

CONCLUSIONS

Treatment of distal femur fractures with the LISS is associated with high union rates without autogenous bone grafting (93%), a low incidence of infection (3%), and maintenance of distal femoral fixation (100%). No loss of fixation in the distal femoral condyles was observed despite the treatment of 30 patients older than 65 years. The LISS is an acceptable surgical option for treatment of distal femoral fractures.

Early results of the less invasive stabilization system for mechanically unstable fractures of the distal femur (AO/OTA types A2, A3, C2, and C3)

OBJECTIVES

Historically, mechanically unstable fractures of the distal femur have been difficult to treat. Problems such as varus collapse, malunion, and nonunion frequently resulted before fixed-angle plates and indirect reduction techniques were popularized. More recently, the Less Invasive Stabilization System, or LISS (Synthes, Paoli, PA), has been designed to combine these 2 approaches with the intended goals of achieving adequate stable fixation and early healing. Early clinical results for the femoral Less Invasive Stabilization System have been promising. The purpose of this study is to evaluate the clinical results of patients with high energy, mechanically unstable fractures of the distal femur treated with the Less Invasive Stabilization System.

DESIGN

Retrospective analysis of a treatment protocol, consecutive patient series.

SETTING

Busy level II trauma center. PATIENTS /PARTICIPANTS: Twenty-six patients with 27 high-energy AO/OTA types A2, A3, C2, and C3 fractures of the distal femur.

INTERVENTION

Treatment with indirect fracture reduction and internal distal femoral fixation using the Less Invasive Stabilization System.

MAIN OUTCOME MEASUREMENTS

Clinical and radiographic assessment.

RESULTS

Twenty-one patients with 22 fractures were available for evaluation at an average 19 months postinjury (range 12-35 months). The mechanism of injury included 12 motor vehicle collisions, 4 high falls, 5 motorcycle crashes, and 1 bicyclist struck by a car. Twenty patients had associated injuries. Six fractures were open. All fractures were comminuted; according to the AO/OTA fracture classification there were 4 A2, 3 A3, 12 C2, and 3 C3 fractures. All fractures healed without secondary surgeries at a mean of 13 weeks (range 7-16 weeks). There were no cases of failed fixation, implant breakage, or infection. Average joint line orientation relative to the femoral shaft axis (valgus) measured 99 degrees on postoperative radiographs and 99 degrees on final radiographs. A comparison of postoperative to healed final radiographs for each femur demonstrated no case with greater than a 3 degrees difference in either varus or valgus. Complications included 1 mal-union where the fracture was fixed in 8 degrees of valgus and 2 cases of external rotation between 10 degrees and 15 degrees. Painful hardware occurred in 4 patients, of which 3 underwent implant removal. The average knee range of motion was 5 degrees to 114 degrees.

CONCLUSIONS

The Less Invasive Stabilization System allows for stable fixation and facilitates early healing in mechanically unstable high-energy fractures of the distal femur. There were no patients with fixation failure, varus collapse, or nonunion in this "at-risk" population. This treatment safely allows for immediate postoperative initiation of joint mobility and the progression of weight bearing with early radiographic signs of healing.