Fixation technique influences osteogenesis of comminuted fractures

Hospitalization for computer-assisted hexapod ring fixation application – analyses of patient variability, peri-operative complications, hospital costs, and discharge status

Background

Computer-assisted hexapod ring fixation systems (HRF) are used for multiple conditions and in very diverse patient populations. This study analyzes perioperative outcomes following HRF application based on patient etiology and clinical presentation.

Methods

Data from patients in the Premier Hospital Billing Database between 2007–2019 undergoing HRF application were analyzed for the duration of patients’ hospitalizations. Patients were grouped based on etiology: acquired deformity, arthrosis, congenital deformity, deep infection, infected nonunion, fracture, nonunion, and other post-operative complications. Demographics, comorbidities, operating room time (ORT), length of stay (LOS), peri-operative complications, and hospital costs were estimated using generalized linear models. Logistic regression evaluated factors associated with peri-operative complications.

Results

One thousand eight hundred eighteen patients (average age: 46.9, standard deviation (SD) (19.6) – 38.9% female) were included in the study, and included 72% fracture cases, 9.6% deep infection, 10.2% deformity (acquired: 5.9%, congenital: 4.3%), 4.2% nonunions, 2% arthrosis and 1.4% other sequelas from prior fractures. Comorbidities varied across diagnosis categories and age, 40% adults and 86% pediatric had no comorbidities. Pediatric cases mostly suffered from obesity (16.1%) and pulmonary disease (10.7%). Complicated diabetes was present in 45.9% of arthropathy and 34.3% of deep infection patients. ORT, LOS and inflation-adjusted hospital costs for all patients averaged 277.7 min (95% Confidence interval (CI): 265.1–290.3), 7.07 days (95% CI: 6.6–7.5) and $41,507 (95%CI: $39,728-$43,285), respectively, but were highest in patients with deep infection (ORT: 369 min (95%CI: $321.0-$433.8); LOS: 14.4 days (95%CI: $13.7-$15.1); Cost: $54,666 (95%CI: $47,960-$63,553)). The probability of having an intraoperative complication averaged 35% (95%CI: 28%-43%) in adult patients with deep infection vs 7% (95%CI: 2%-20%) in pediatric cases treated for congenital deformity. The risk for intraoperative complications was mostly associated with preexisting comorbidities, an Elixhauser > 5 was the most predictive risk factor for complications (odds ratios: 4.53 (95%CI: 1.71–12.00, p = 0.002).

Conclusions

There is important heterogeneity among HRF patients. Adults with HRF for fracture, deep infection and arthrosis are at far greater risk for peri-operative complications vs. patients with deformity, especially pediatric deformity cases, mostly due to existing comorbidities and age. Device-specific HRF clinical studies cannot be generalized beyond their exact patient population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05171-6.

Comparison between intramedullary nailing and minimally invasive plate osteosynthesis for tibial shaft fractures

INTRODUCTION

Intramedullary nailing (IMN) is currently considered the gold standard in the surgical treatment of tibial shaft fractures in adult patients. In this case-control comparative study, we aimed to compare the efficacy of minimally invasive plate osteosynthesis (MIPO) and IMN in treating tibial shaft fractures.

MATERIALS AND METHODS

The clinical and radiological outcomes, such as a modified trauma scale, operation time, fracture healing, rate of re-operation, and complications such as malunion, nonunion, shortening, and infection were assessed between IMN and MIPO for the treatment of tibial shaft fractures.

RESULTS

Seventy-three skeletally mature patients who underwent IMN (group I) or MIPO (group M) for a closed extra-articular tibial shaft fracture (AO/OTA type 42) from June 2010 to May 2016 were retrospectively reviewed. The mean age was 51.16 (18~79) years, and the mean follow-up period was 22 (12~50) months. Bony union was achieved in all cases but one for each group - group I (35 cases) and group M (36 cases) (p > 0.05). Mean callus formation was observed in 12 (8 - 16) weeks in both groups (p > 0.05). There was no significant difference in operative time, hospital stay, bone healing, and the rate of complications among the two groups (p > 0.05). There was also no postoperative difference in functional evaluation between the two methods (p > 0.05).

CONCLUSIONS

No discrepancy was found in radiological and clinical outcomes between IMN and MIPO for tibial shaft fractures. It can be concluded that both IMN and MIPO are equally effective treatment modalities for tibial shaft fractures.

Systematic Review of the Preclinical Technology Readiness of Orthopedic Gene Therapy and Outlook for Clinical Translation

Bone defects and improper healing of fractures are an increasing public health burden, and there is an unmet clinical need in their successful repair. Gene therapy has been proposed as a possible approach to improve or augment bone healing with the potential to provide true functional regeneration. While large numbers of studies have been performed in vitro or in vivo in small animal models that support the use of gene therapy for bone repair, these systems do not recapitulate several key features of a critical or complex fracture environment. Larger animal models are therefore a key step on the path to clinical translation of the technology. Herein, the current state of orthopedic gene therapy research in preclinical large animal models was investigated based on performed large animal studies. A summary and an outlook regarding current clinical studies in this sector are provided. It was found that the results found in the current research literature were generally positive but highly methodologically inconsistent, rendering a comparison difficult. Additionally, factors vital for translation have not been thoroughly addressed in these model systems, and the risk of bias was high in all reviewed publications. These limitations directly impact clinical translation of gene therapeutic approaches due to lack of comparability, inability to demonstrate non-inferiority or equivalence compared with current clinical standards, and lack of safety data. This review therefore aims to provide a current overview of ongoing preclinical and clinical work, potential bottlenecks in preclinical studies and for translation, and recommendations to overcome these to enable future deployment of this promising technology to the clinical setting.

Minimally invasive plate osteosynthesis (MIPO) for mid-shaft fracture of the tibia (AO/OTA classification 42): A retrospective study

BACKGROUND

There is abundance of literature regarding the treatment of tibial mid-shaft fracture, and intramedullary nailing (IMN) is described as the treatment of choice. However, problems such as malunion and knee pain are known disadvantages of this approach. Minimally invasive plate osteosynthesis (MIPO) technique is another treatment option for tibial mid-shaft fracture.The purpose of this study is to evaluate the clinical, radiological results, and complication rates of tibial mid-shaft fractures treated with MIPO technique.

MATERIALS AND METHOD

Thirty-seven skeletally mature patients who underwent MIPO for a mid-shaft fracture of tibia (AO/OTA classification 42) from June 2016 to May 2018 were retrospectively reviewed. A total of 37 patients (12 females, 25 males) with a mean age of 52.7 years (range 28-78 years) were included. The clinical and radiological outcomes, such as the Jeju Lower Extremity Trauma Scale (JLETS), time to callus formation, time to bony union, and complications such as delayed union, malunion, nonunion, and infection were assessed.

RESULTS

Bony union was achieved in all cases but one (36 cases). Average callus formation was observed in 10.7 (6.5-14.5) weeks. The average time to union was 19.8 (11.5-26.5) weeks. The average JLETS score was 46.9 (40-53) point. Malunion deformities were observed in 3 cases (8.1%). Two superficial infection cases all resolved spontaneously. There was no statistically significant difference in clinical and radiographic outcomes by different AO/OTA fracture types.

CONCLUSION

The MIPO technique with locking compression plate provides stable fixation and satisfactory clinical and radiological results for mid-shaft fractures of tibia irrespective of the fracture type. Future study should aim to compare MIPO and IMN cases directly to clarify the differences and similarities between the two treatment modalities.

Pediatric Femoral Shaft Fracture: An Age-Based Treatment Algorithm

PURPOSE

Fractures of the femoral shaft in children are common. The rates of bone growth and remodeling in children vary according to their ages, which affect their respective management.

METHODS

This paper evaluates the incidence and patterns of pediatric femoral shaft fracture and the current concepts of treatments available.

RESULTS

The type of fracture-closed or open; stable or unstable-needs to be taken into account. Child abuse should be suspected in fractures sustained by infants. For younger children, non-surgical management is preferred, which include Pavlik harness (< 6 months old) and early spica casting (6 months to 6 years old). Older children (> 6 years old) usually benefit from surgical treatments as outcomes of non-surgical alternatives are worse and are associated with prolonged recovery times. These operative measures for older children that are 6-12 years old include elastic stable intramedullary nailing and submuscular plating. Factors to be considered when devising an appropriate intervention include body mass, location of injury, and nature of fracture. For adolescent and skeletally mature teenagers (> 12 years old), rigid antegrade entry intramedullary fixation is indicated. In the event of open fractures or polytrauma, external fixation should be considered as a temporary treatment method for initial fracture stabilization.

CONCLUSION

An age-based and evidence-based algorithm has been proposed to guide surgeons in the process of evaluating an appropriate treatment.

Non-union: Indications for external fixation

External fixation is currently used as the definitive mode of fracture stabilisation in the management of ˜50% of long-bone non-unions. Distinction between non-union and delayed union is a diagnostic dilemma especially in fractures healing by primary bone repair. This distinction is important, as non-unions are not necessarily part of the same spectrum as delayed unions. The aetiology of a fracture non-union is usually multifactorial and the factors can be broadly categorized into mechanical factors, biological (local and systemic) factors, and infection. Infection is present in ˜40% of fracture non-unions, often after open fractures or impaired wound healing, but in 5% of all non-unions infection is present without any clinical or serological suspicion. General indications for external fixation include clinical scenarios where; 1) percutaneous correction of alignment, or mechanical stimulation of the non-union site is required; 2) fixation of juxta-articular or 'emmental' bone fragments is necessary; and 3) staged bone or soft tissue reconstruction is anticipated. Specific anatomical indications include infected non-unions of the tibia, humerus, and juxta-articular bone. External fixation is an essential tool in the management of fracture non-unions. However, with greater understanding of the outcomes associated with both external and internal fixation the relative indications are now being refined.

End-threaded intramedullary positive profile screw ended self-tapping pin (Admit pin) - A cost-effective novel implant for fixing canine long bone fractures

Aim

The current study was undertaken to evaluate the clinical efficacy of end-threaded intramedullary pinning for management of various long bone fractures in canines.

Materials and Methods

This study was conducted in two phases, managing 25 client-owned dogs presented with different fractures. The technique of application of end-threaded intramedullary pinning in long bone fractures was initially standardized in 6 clinical patients presented with long bone fractures. In this phase, end-threaded pins of different profiles, i.e., positive and negative, were used as the internal fixation technique. On the basis of results obtained from standardization phase, 19 client-owned dogs clinically presented with different fractures were implanted with end-threaded intramedullary positive profile screw ended self-tapping pin in the clinical application phase.

Results

The patients, allocated randomly in two groups, when evaluated postoperatively revealed slight pin migration in Group-I (negative profile), which resulted in disruption of callus site causing delayed union in one case and large callus formation in other two cases whereas no pin migration was observed in Group-II (positive profile). Other observations in Group-I was reduced muscle girth and delayed healing time as compared to Group-II. In clinical application, phase 21^st and 42^nd day post-operative radiographic follow-up revealed no pin migration in any of the cases, and there was no bone shortening or fragment collapse in end-threaded intramedullary positive profile screw ended self-tapping pin.

Conclusion

The end-threaded intramedullary positive profile screw ended self-tapping pin used for fixation of long bone fractures in canines can resist pin migration, pin breakage, and all loads acting on the bone, i.e., compression, tension, bending, rotation, and shearing to an extent with no post-operative complications.

Ilizarov external fixation versus plate internal fixation in the treatment of end-stage ankle arthritis: decision analysis of clinical parameters

The purpose of this study was to evaluate the effect of Ilizarov external fixation (IEF) and plate internal fixation (PIF) in the treatment of end-stage ankle arthritis on pain relieving and function improvement. The study cohort consisted of 59 patients with end-stage ankle arthritis underwent ankle arthrodesis with IEF or PIF between June 2011 and June 2015. Standard radiographs and computed tomography (CT) scans were obtained before surgery and during the follow-up. Functional assessments were performed using Foot and Ankle pain score of American Orthopedics Foot and Ankle Society (AOFAS) and Visual Analogue Scale (VAS). The average AOFAS scores in both IEF group and PIF groups increased significantly after operation, from 45.5 ± 6.3 to 84.8 ± 4.9 and from 45.9 ± 6.6 to 86.6 ± 5.4, respectively. The average VAS scores in both groups decreased significantly after operation, from 8.4 ± 1.9 to 2.5 ± 0.6 and from 8.2 ± 1.5 to 2.3 ± 0.7, respectively. Nevertheless, there was no significant difference for preoperative or postoperative AOFAS and VAS scores between the two groups. The IEF would result in comparable postoperative functional recovery and pain relieving to PIF and may be an effective substitute to PIF in the treatment of end-stage ankle arthritis.

Severe tibial plateau fractures (Schatzker V-VI): open reduction and internal fixation versus hybrid external fixation

Tibial plateau fractures (TPF) are highly prone to complications and adverse effects. Their treatment has long been a matter of controversy, as fracture patterns and possible damage to soft tissues can easily aggravate complications. On the one hand, open reduction and internal fixation (ORIF) techniques provide a good approach to joint shape restoration and biomechanics, but they may also provoke a higher rate of soft-tissue complications. On the other, hybrid external fixation (HEF), although allowing little facility for reduction, may, theoretically, produce much less damage to the soft tissues. We present 93 cases of TPF classified as type V or VI that were followed up for at least 24 months. There were no statistical differences among them in relation to consolidation, secondary malalignment or range of motion, according to whether ORIF or HEF was employed. However, when external fixation followed open reduction, both superficial and deep-infection rates were higher.

The management of paediatric diaphyseal femoral fractures: a modern approach

The definitive treatment of paediatric femoral diaphyseal fractures remains controversial. Modalities of treatment vary mostly according to age, with fracture pattern and site having a lesser impact. Current evidence is reflective of this variation with most evidence cited by the American Academy of Orthopedic Surgeons being level 4 or 5. The authors present a review of the most up-to-date evidence relating to the treatment of these fractures in each age group. In an attempt to clarify the current trends, we have produced an algorithm for decision-making based on the experience from our own tertiary referral level 1 major trauma centre.

Peri-implant failure in dual plating of the distal humerus-A biomechanical analysis with regard to screw and plate positioning

PURPOSE

The aim of this biomechanical study was to analyse the influence of plate and screw positioning on peri-implant failure in dual plate osteosynthesis. We hypothesized that screw positioning rather than plate configuration influences the risk of peri-implant fractures.

METHODS

Twenty macerated humerus specimens were available. 5 groups of 4 were built according to specimen size. Locking dual plates (Medartis, Switzerland) were randomly applied to the distal humerus of the specimens in 4 types of configuration: Bending forces were applied using a universal testing machine until peri-implant fracture occurred.

RESULTS

Mean failure loads for respective configuration types were as follows: P1: 428.7 (±84.2) N, A1: 410.0 (±54.7) N, A0: 297.8 (±48.3) N, P0: 261.0 (±65.0) N. Configurations with positioning of the most proximal screws at different levels (P1, A1) reached significantly higher failure loads when compared to screw placement at the same level (P0, A0) (0.01≤p≤0.03). Altering the plate configuration did not significantly influence failure loads (0.34≤p≤0.58).

CONCLUSIONS

The results of this study suggest that placement of the most proximal screws rather than the configuration of the plates is critical regarding the predetermined risk of peri-implant failure in dual plate osteosynthesis of the distal humerus. Varying levels of the outermost screws of corresponding double plates seem to be crucial to avoid complications related to the osteosynthesis.

Working length of locking plates determines interfragmentary movement in distal femur fractures under physiological loading

BACKGROUND

This study aimed to investigate the influence of the screw location and plate working length of a locking plate construct at the distal femur on interfragmentary movement under physiological loading.

METHODS

To quantitatively analyse the influence of plate working length on interfragmentary movements in a locking plate construct bridging a distal femur fracture, a finite element model based on CT (computed tomography) data was physiologically loaded and fracture gap conditions were calculated. Four working lengths with eight screw variations each were systemically analysed.

FINDINGS

Interfragmentary movements for axial (12-19%, p<0.001) and shear movements (-7.4-545%, p<0.001) at all tested nodes increased significantly with longer plate working length, whereas screw variations within the groups revealed no significant influence. The working length (defined by screw location) dominates the biomechanical fracture gap conditions.

INTERPRETATION

The current finite element analysis demonstrates that plate working length significantly influences interfragmentary movements, thereby affecting the biomechanical consequences of fracture healing.

Non-osteotomy and osteotomy large animal fracture models in orthopedic trauma research

Large animal fracture models are important in the field of orthopedic trauma research. New implants are tested in animals before being implanted into humans. Large animals like sheep or swine often are more properly to simulate conditions in humans, e.g. biomechanical demands, compared to rodents. Cited articles mainly analyze shock or fracture healing. Both osteotomy and non-osteotomy fracture models have been used in the past. However, comparative studies are rare and clear recommendation when to use which model are missing. This review will summarize large animal fracture models putting special emphasis on non-osteotomy fracture models.

Controlled dynamic stability as the next step in "biologic plate osteosynthesis" - a pilot prospective observational cohort study in 34 patients with distal tibia fractures

INTRODUCTION

Delayed bone healing is an eminent problem in the operative treatment of distal tibia fractures. To address this problem from a biomechanical perspective, the DLS 3.7 (Dynamic Locking Screw 3.7 mm) as a new generation of locking screws has been developed. This screw enables the surgeon to control the rigidity of the plate osteosynthesis and thereby to expand clinical options in cases where the bridge plating is chosen for fracture treatment.

PURPOSE

The purpose of the present prospective study was to evaluate the safety use of the DLS 3.7 in distal tibia fractures where bridge plating osteosynthesis is recommended.

METHODS

In a prospective non-controlled cohort study, 34 patients with acute distal tibia fractures (AO 43 A-C) were treated with an angular stable plate fixation using DLS 3.7 or LHS 3.5. Follow-up examinations were performed three, six, twelve, and twenty-four weeks postoperatively and all registered complications were carefully collected.

RESULTS

A total of 34 patients were prospectively enrolled in this study with a minimum follow-up of 6 months or obvious osseous consolidation at an earlier stage. No complications directly related to the DLS 3.7 were recorded and no infections were observed.

CONCLUSIONS

This observational study could show that the DLS 3.7 in combination with locking compression plates provides a secure and easy application. According to the recent literature inter-fragmentary micro-motion is one evident goal to increase the reliability in fracture healing. The new DLS 3.7 with a maximum micro-motion of 0.2 mm combines the advantage of micro-motion with the well-known advantages of angular stable plate fixation.

Effect of plate working length on plate stiffness and cyclic fatigue life in a cadaveric femoral fracture gap model stabilized with a 12-hole 2.4 mm locking compression plate

Background

There are several factors that can affect the fatigue life of a bone plate, including the mechanical properties of the plate and the complexity of the fracture. The position of the screws can influence construct stiffness, plate strain and cyclic fatigue of the implants. Studies have not investigated these variables in implants utilized for long bone fracture fixation in dogs and cats. The purpose of the present study was to evaluate the effect of plate working length on construct stiffness, gap motion and resistance to cyclic fatigue of dog femora with a simulated fracture gap stabilized using a 12-hole 2.4 mm locking compression plates (LCP). Femora were plated with 12-hole 2.4 mm LCP using 2 screws per fracture segment (long working length group) or with 12-hole 2.4 mm LCP using 5 screws per fracture segment (a short working length group).

Results

Construct stiffness did not differ significantly between stabilization techniques. Implant failure did not occur in any of the plated femora during cycling. Mean ± SD yield load at failure in the short plate working length group was significantly higher than in the long plate working length group.

Conclusion

In a femoral fracture gap model stabilized with a 2.4 mm LCP applied in contact with the bone, plate working length had no effect on stiffness, gap motion and resistance to fatigue. The short plate working length constructs failed at higher loads; however, yield loads for both the short and long plate working length constructs were within physiologic range.

Biological fixation of fracture shaft femur in children

The aim of this work was to assess the results of biological fixation of fracture shaft femur in children with locked plates. Twenty-eight fractures in 26 children with closed fractures of the shaft of the femur were managed with biological plating using locked plates bridging the fracture site applied submuscularly through two small incisions above and below the fracture site. The mean age of the patients was 11.2 years; all patients had radiological union within a mean time of 11.9 weeks (8-14 weeks); the average follow-up was 31 months (14-40 months). No patient had frontal or sagittal plane deformity more than 10° or limb length discrepancy more than 1.5 cm. There was no infection, delayed union, nonunion or clinically evident malrotation. A significant positive correlation between the age and the time to healing (p = 0.03) was detected, whereas there was no significant correlation between time to healing and patient sex, fracture level, fracture type, mechanism of injury. Also there was no significant correlation between limb length discrepancy and patient age, sex, fracture level, fracture type, and mechanism of injury. Biological fixation of fractures of the femoral shaft in children with locked plates is a reliable method of fixation with excellent healing potential and fixation mechanics without complications.

In vivo models of bone repair

This review is aimed at clinicians appraising preclinical trauma studies and researchers investigating compromised bone healing or novel treatments for fractures. It categorises the clinical scenarios of poor healing of fractures and attempts to match them with the appropriate animal models in the literature.

We performed an extensive literature search of animal models of long bone fracture repair/nonunion and grouped the resulting studies according to the clinical scenario they were attempting to reflect; we then scrutinised them for their reliability and accuracy in reproducing that clinical scenario.

Models for normal fracture repair (primary and secondary), delayed union, nonunion (atrophic and hypertrophic), segmental defects and fractures at risk of impaired healing were identified. Their accuracy in reflecting the clinical scenario ranged greatly and the reliability of reproducing the scenario ranged from 100% to 40%.

It is vital to know the limitations and success of each model when considering its application.

Fracture healing under healthy and inflammatory conditions

Optimal fracture treatment requires knowledge of the complex physiological process of bone healing. The course of bone healing is mainly influenced by fracture fixation stability (biomechanics) and the blood supply to the healing site (revascularization after trauma). The repair process proceeds via a characteristic sequence of events, described as the inflammatory, repair and remodeling phases. An inflammatory reaction involving immune cells and molecular factors is activated immediately in response to tissue damage and is thought to initiate the repair cascade. Immune cells also have a major role in the repair phase, exhibiting important crosstalk with bone cells. After bony bridging of the fragments, a slow remodeling process eventually leads to the reconstitution of the original bone structure. Systemic inflammation, as observed in patients with rheumatoid arthritis, diabetes mellitus, multiple trauma or sepsis, can increase fracture healing time and the rate of complications, including non-unions. In addition, evidence suggests that insufficient biomechanical conditions within the fracture zone can influence early local inflammation and impair bone healing. In this Review, we discuss the main factors that influence fracture healing, with particular emphasis on the role of inflammation.

Dynamic plate osteosynthesis for fracture stabilization: how to do it

Plate osteosynthesis is one treatment option for the stabilization of long bones. It is widely accepted to achieve bone healing with a dynamic and biological fixation where the perfusion of the bone is left intact and micromotion at the fracture gap is allowed. The indications for a dynamic plate osteosynthesis include distal tibial and femoral fractures, some midshaft fractures, and adolescent tibial and femoral fractures with not fully closed growth plates. Although many lower limb shaft fractures are managed successfully with intramedullary nails, there are some important advantages of open-reduction-and-plate fixation: the risk of malalignment, anterior knee pain, or nonunion seems to be lower. The surgeon performing a plate osteosynthesis has the possibility to influence fixation strength and micromotion at the fracture gap. Long plates and oblique screws at the plate ends increase fixation strength. However, the number of screws does influence stiffness and stability. Lag screws and screws close to the fracture site reduce micromotion dramatically.

Dynamic plate osteosynthesis can be achieved by applying some simple rules: long plates with only a few screws should be used. Oblique screws at the plate ends increase the pullout strength. Two or three holes at the fracture site should be omitted. Lag screws, especially through the plate, must be avoided whenever possible. Compression is not required. Locking plates are recommended only in fractures close to the joint. When respecting these basic concepts, dynamic plate osteosynthesis is a safe procedure with a high healing and a low complication rate.

Advancements in percutaneous fixation for foot and ankle trauma

Operative fixation of foot and ankle trauma can be challenging. Often times, the soft tissue envelope can have extensive damage as a result of the fracture. In these cases, percutaneous fixation may be used. Percutaneous fixation can benefit both soft tissue and osseous healing when used correctly. Many techniques have been described in the literature that may help to preserve blood supply, minimize soft tissue dissection, and restore a functional limb. This article reviews general guidelines for fracture and soft tissue management, osseous healing of fractures, and how certain techniques influence fracture healing. It also illustrates certain techniques for specific fracture reduction.

Biomechanical principles and mechanobiologic aspects of flexible and locked plating

The goal of minimally invasive surgery in extramedullary internal fixation has led to the development of flexible plates, bridging plates, and locked internal fixators. The change from conventional compression plates to these new implants, however, resulted in different biomechanics of fixation and different mechanobiologic processes for fracture healing. The aim of a flexible fixation is the stimulation of fracture healing by callus formation. Fracture healing follows mechanobiologic rules based mainly on interfragmentary strain, which is dependent on the stability of the fixation construct and the type of fracture. Knowledge of the mechanobiologic processes and the factors influencing the stability of fracture fixation are necessary for the surgeon to choose the correct technique for fracture fixation. Problems in the selection of the correct technique and limitations with the available implants as well as possible future developments are discussed.

Bicondylar tibial fractures: Internal or external fixation?

Bicondylar fractures of the tibia, representing the Schatzker V and VI fractures represent a challenging problem. Any treatment protocol should aim at restoring articular congruity and the metaphyseo-diaphsyeal dissociation (MDD)-both of these are equally important to long-term outcome. Both internal and external fixations have their proponents, and each method of treatment is associated with its unique features and complications. We review the initial and definitive management of these injuries, and the advantages and disadvantages of each method of definitive fixation. We suggest the use of a protocol for definitive management, using either internal or external fixation as deemed appropriate. This protocol is based on the fracture configuration, local soft tissue status and patient condition. In a nutshell, if the fracture pattern and soft tissue status are amenable plate fixation (single or double) is performed, otherwise limited open reduction and articular surface reconstruction with screws and circular frame is performed.

Principles of fracture fixation in orthopaedic trauma surgery

Fractures are common injuries and their management has evolved over the last 30 years with a greater propensity to treat fractures surgically. There have also been advances in the understanding of the principles of bone healing and the implications on implant choice. This article highlights the various surgical fixation devices available for the management of fractures and their underlying principles of action.

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.

Minimally invasive treatment of pilon fractures with a low profile plate: preliminary results in 17 cases

OBJECTIVE

To determine the results of "biologic fixation" with a minimally invasive plating technique using a newly designed low profile "Scallop" plate in the treatment of pilon fractures.

DESIGN

Retrospective case series.

SETTING

A tertiary referral center.

PATIENTS/PARTICIPANTS

Seventeen patients were treated between 1999 and 2001 for a tibial plafond fracture at the Hospital for Special Surgery with a newly designed low-profile plate. Eleven of the fractures (65%) were high-energy injuries. Two fractures were open.

INTERVENTION

Staged surgical treatment with open reduction and fixation of the fibular fracture and application of an external fixator was performed in 12 cases. As soon as the soft tissues and swelling allowed, i.e. skin wrinkling, the articular surface was reconstructed and simply reduced, if necessary through an small incision, and the articular block was fixed to the diaphysis using a medially placed, percutaneously introduced flat scallop plate. In the remaining five cases the operation was performed in one session.

MAIN OUTCOME MEASUREMENTS

Time to healing and complications including delayed union, non-union, instrument failure, loss of fixation, infection, quality of reduction and number of reoperations were evaluated. Quality of results and outcome were graded using the ankle-hindfoot-scale and a modified rating system.

RESULTS

All patients went on to bony union at an average time of 14 weeks. There were no plate failures or loss of fixation/reduction. Two superficial wound-healing problems resolved with local wound care. At an average follow up of 17 months (range 6-29 months) eight patients (47%) had an excellent result; seven (41%) had a fair result whereas two (12%) had a poor result. The average ankle-hindfoot-score was 86.1 (range 61-100). Four patients have had the hardware removed and one of them is awaiting an ankle arthrodesis.

CONCLUSIONS

Based on these initial results, it appears that a minimally invasive surgical technique including new low profile plate can decrease soft tissue problems while leading to fracture healing and obtaining results comparable with other more recent series. We believe that this new "Scallop Plate" is effective for the treatment of pilon fractures and should be used in conjunction with a staged procedure in the acute trauma setting.

Long-term effects of saw osteotomy versus random fracturing on bone healing and remodeling in a sheep tibia model

This article is about the evaluation of possible differences in biomechanical or histomorphological properties of bone healing between saw osteotomy and random fracturing after 6 months. A standardized, 30 degrees oblique monocortical saw osteotomy of sheep tibia was carried out, followed by manual fracture completion of the opposed cortical bone. Fixation was performed by bridge plating (4.5 mm, LCDCP, broad). X-rays were taken immediately after surgery and at the end of the study. Polychrome fluorescent staining was performed according to a standardized protocol in the 2nd, 4th 6th, 10th, 14th, 18th, 22th and 26th week. Ten sheep were comprehensively evaluated. Data for stiffness and histomorphology are reported. The average bending stiffness of the operated bone was higher (1.7 (SD 0.3) with plate (MP) vs. 1.5 without plate) than for the intact bone (1.4 (SD 0.2), though no significant differences in bending stiffness were observed (P>0.05). Fluorescence staining revealed small numbers of blood vessels and less fragment resorption and remodeling in the osteotomy gap. Bone healing after saw osteotomy shows a very close resemblance to 'normal' fracture healing. However, vascular density, fragment resorption, fragment remodeling, and callus remodeling are reduced at the osteotomy.

Sensitivity of tissue differentiation and bone healing predictions to tissue properties

Computational models are employed as tools to investigate possible mechano-regulation pathways for tissue differentiation and bone healing. However, current models do not account for the uncertainty in input parameters, and often include assumptions about parameter values that are not yet established. The aim was to clarify the importance of the assumed tissue material properties in a computational model of tissue differentiation during bone healing. An established mechano-biological model was employed together with a statistical approach. The model included an adaptive 2D finite element model of a fractured long bone. Four outcome criteria were quantified: (1) ability to predict sequential healing events, (2) amount of bone formation at specific time points, (3) total time until healing, and (4) mechanical stability at specific time points. Statistical analysis based on fractional factorial designs first involved a screening experiment to identify the most significant tissue material properties. These seven properties were studied further with response surface methodology in a three-level Box-Behnken design. Generally, the sequential events were not significantly influenced by any properties, whereas rate-dependent outcome criteria and mechanical stability were significantly influenced by Young's modulus and permeability. Poisson's ratio and porosity had minor effects. The amount of bone formation at early, mid and late phases of healing, the time until complete healing and the mechanical stability were all mostly dependent on three material properties; permeability of granulation tissue, Young's modulus of cartilage and permeability of immature bone. The consistency between effects of the most influential parameters was high. To increase accuracy and predictive capacity of computational models of bone healing, the most influential tissue mechanical properties should be accurately quantified.

Are locking screws advantageous with plate fixation of humeral shaft fractures? A biomechanical analysis of synthetic and cadaveric bone

OBJECTIVES

To investigate whether locking screws offer any advantage over nonlocking screws for plate fixation of humeral shaft fractures for weight-bearing applications.

DESIGN

: Mechanical evaluation of stiffness in torsion, bending, and axial loading and failure in axial loading in synthetic and cadaveric bone.

SETTING

Biomechanical laboratory in an academic medical center.

METHODS

: We modeled a comminuted midshaft humeral fracture in both synthetic and cadaveric bone. Humeri were plated posteriorly. Two study groups each used identical 10-hole, 3.5-mm locking compression plates that can accept either locking or nonlocking screws. The first group used only nonlocking screws and the second only locking screws. Stiffness testing and failure testing were performed for both the synthetic bones (n = 6) and the cadaveric matched pairs (n = 12). Fatigue testing was set at 90,000 cycles of 440 N of axial loading.

MAIN OUTCOME MEASURES

Torsion, bending, and axial stiffness and axial failure force after cyclic loading.

RESULTS

With synthetic bones, no significant difference was observed in any of the 4 tested stiffness modes between the plates with locking screws and those with nonlocking screws (anteroposterior, P = 0.51; mediolateral, P = 0.50; axial, P = 0.15; torsional, P = 0.08). With initial failure testing of the constructs in axial loading, both plates failed above anticipated physiologic loads of 440 N (mean failure load for both constructs >4200 N), but no advantage to locking screws was shown. The cadaveric portion of the study also showed no biomechanical advantage of locking screws over nonlocking screws for stiffness of the construct in the 4 tested modes (P > 0.40). Fatigue and failure testing showed that both constructs were able to withstand strenuous fatigue and to fail above anticipated loads (mean failure >3400 N). No difference in failure force was shown between the 2 groups (P = 0.67).

CONCLUSIONS

Synthetic and cadaveric bone testing showed that locking screws offer no obvious biomechanical benefit in this application.

Prospective outcomes of comminuted periarticular metacarpal and phalangeal fractures treated using a titanium plate system

PURPOSE

The purpose of this study was to prospectively evaluate clinical results for open reduction and internal fixation of unstable metaphyseal fractures of the metacarpal and phalangeal bones using a miniature titanium plate.

METHODS

Fifty-one consecutive patients with periarticular fractures with metaphyseal comminution and displacement were enrolled. Intra-articular involvement with a split or depression fracture was identified in 22 hands. Minimum follow-up was 1 year. There were 37 male and 14 female patients; average age was 38 years (range, 14-63). Of the 51 fractures, 15 were open; 8 of these had additional soft tissue injury, involving neurovascular injury in 4 and extensor tendon injury in 6. The average duration from injury to surgery was 6 days (range, 2-40 days).

RESULTS

Bone union was successfully achieved in all patients over an average period of 2.6 months. The final range of total active motion (%TAM) was excellent (>85%) for 26, good (70%-84%) for 17, fair (50%-69%) for 5, and poor (<49%) for 3. Postoperative complications occurred in 5 patients, including fracture redisplacement in 2, a collapse or absorption of the condylar head in 2, and superficial infection due to hardware exposure in one. Subsequently, 2 of these patients had malrotation deformities or osteoarthritic changes in the injured finger. Plates were removed in 30 cases, and additional surgery was required in 20 cases. Postoperative grip strength averaged 87% of the contralateral side. Statistical analysis revealed that patient age was significantly correlated with %TAM of the injured finger at 1-year follow-up (p < .01), and intra-articular (p < .05) and phalangeal bone (p < .01) involvement, as well as associated soft tissue injury (p < .05), significantly affected the range of finger motion.

CONCLUSIONS

Despite the technical demands of plating for comminuted metacarpal and phalangeal fractures, the low-profile titanium plate system was highly effective in maintaining anatomic reduction. The postoperative complication rate was relatively low, and the objective outcomes approached a reasonable level at 1-year follow-up.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Lateral approach for fixation of the fractures of the distal tibia. Outcome of 20 patients. Technical note

INTRODUCTION

The treatment of fractures of the distal third of the tibia remains still controversial. It is often difficult to get and retain good reduction by non-operative or nailing methods. Open reduction and plate fixation offers good reduction and retention of the achieved position. However, increased soft tissue damage and high complication rate has led to search less invasive surgical methods such as minimal invasive plating technique.

MATERIAL AND METHODS

Lateral approach for the distal tibia allows to reduce and to plate both the fibula and the tibia using only one skin incision. We have used lateral approach for 20 consecutive tibia fracture patients and report clinical and radiological results after an average follow-up of 31 months.

RESULTS

All fractures united, but two malunions were developed after good primary reduction. Seventeen patients achieved excellent or good subjective result while one had moderate and two poor results. Four superficial wound infections were noticed and they were treated conservatively.

CONCLUSION

We conclude that lateral approach for the distal tibia is a demanding, but useful surgical method for treatment of the distal tibia fractures especially in cases where no medial comminution of the tibia is present and when the fibula has to be fixed, too.

Nail-assisted percutaneous plating of pediatric femoral fractures

Traditional operative treatments for pediatric femoral shaft fractures may result in an unacceptable complication rate, especially in patients with complex fractures. Despite requiring the use of fluoroscopy and presenting some technical difficulty, minimally invasive percutaneous plating is an alternative operative method. We retrospectively reviewed 13 consecutive femoral fractures in children (mean age, 9 years) who were treated by a modified technique of percutaneous plating. Six of the fractures were comminuted. Nine children had associated injuries, including four with head trauma. The primary indication for use of percutaneous plating in this pediatric series was a complex fracture in which flexible nailing would be suboptimal. The results were evaluated by a modification of Flynn's criteria. All fractures united without bone grafts (mean, 11 weeks). No patients had residual radiographic angulations greater than 10 degrees or a leg-length discrepancy greater than 5 mm. All patients had excellent final outcomes. There were no major complications such as deep infection or refracture. The technique provided adequate stability for early functional treatment and predictable healing with maintenance of leg length and alignment. Provisional reduction and stabilization of complex pediatric femoral fractures can facilitate definitive percutaneous plating.

Treatment of tibial fractures with plates using minimally invasive percutaneous osteosynthesis in dogs and cats

OBJECTIVES

The aim of the here described case series was to develop and evaluate the minimally invasive percutaneous osteosynthesis for the plate fixation of tibial fractures in dogs and cats.

METHODS

Six dogs and four cats with shaft fractures of the tibia were treated using minimally invasive percutaneous osteosynthesis. Follow-up radiographs four to six weeks after fracture fixation were evaluated for fracture healing. For the long-term follow-up (minimum 2.4 years), owners were contacted by phone to complete a questionnaire.

RESULTS

All fractures healed without the need for a second procedure. Follow-up radiographs obtained after four to six weeks in seven cases showed advanced bony healing with callus formation and filling of the fracture gaps with calcified tissue in all seven. All the patients had a good to excellent long-term result with full limb function. The time needed for regaining full limb use was two to three months.

CLINICAL SIGNIFICANCE

Minimally invasive percutaneous osteosynthesis seems to be a useful technique for the treatment of tibial shaft fractures in dogs and cats.

The mechanics of external fixation

External fixation has evolved from being used primarily as a last resort fixation method to becoming a main stream technique used to treat a myriad of bone and soft tissue pathologies. Techniques in limb reconstruction continue to advance largely as a result of the use of these external devices. A thorough understanding of the biomechanical principles of external fixation is useful for all orthopedic surgeons as most will have to occasionally mount a fixator throughout their career. In this review, various types of external fixators and their common clinical applications are described with a focus on unilateral and circular frames. The biomechanical principles that govern bony and fixator stability are reviewed as well as the recommended techniques for applying external fixators to maximize stability. Additionally, we have illustrated methods for managing patients while they are in the external frames to facilitate function and shorten treatment duration.

A compression force comparison study among three staple fixation systems

Traditional staples have recently been redesigned with both new materials and engineering techniques to facilitate interfragmentary compression in theory, resulting in greater friction between bone fragments to counteract shearing forces. In the current study, the biomechanical properties of 3 different staples were investigated. The interfacial force at 2 different sites within a calcaneal bone model was measured after insertion and activation of the OSStaple, the UNI-CLIP, and the Smith and Nephew Standard Large Staple after precompression with the SYNTHES Small Distractor. Additionally, the ability of each staple to maintain compression over a short period of time was investigated. In the current bench study, the OSStaple consistently generated the greatest and most uniform compression across the bone model osteotomy and was also capable of sustaining the compression over the duration of all of the trials.

Treatment of high-energy tibial plateau fractures

Treatment of high-energy fractures of the tibial plateau requires an inordinate degree of surgical effort in order to avoid complications. Fracture reduction can be a challenge to experienced hands and the soft tissue conditions are intolerant of careless dissection. In general, it is an oversimplification to use one technique of stabilisation for such a heterogenous group (even within one classification tier). This article describes the specific attributes of Schatzker type 6 injuries (AO 41C) that enable decisionmaking algorithms to be generated and balances the merits for plate stabilisation and external fixation against injury characteristics. A detailed description is given for circular fixation in these injuries to assist those unfamiliar with the technique.

Malunions of the finger metacarpals and phalanges

Many malunions of the finger metacarpals are mild and do not require or justify operative intervention. Early recreation of the fracture or osteotomy is more likely to be rewarded with favorable results than late operation. Rotational malunions of the metacarpals or proximal phalanges may be treated by transverse extra-articular transverse or step-cut osteotomies at or proximal to the malunion site. Rotational malunions of the proximal phalanges as great as 200 in the index, middle, and ring fingers and 300 in the small finger may be managed by transverse extra-articular osteotomy at the adjoining metacarpal base. Angular and combined angular and rotational deformities of the metacarpal can be corrected by closing wedge osteotomy at the malunion site, with adjustment for malrotation when necessary. Angular and combined angular and rotational deformities of the proximal phalanx may be corrected by dorsal opening or lateral opening or closing wedge osteotomy, with derotation when needed. Articular malunions may be treated by osteotomy at the fracture site, a sliding osteotomy of the fracture and its proximal supporting cortex, or extra-articular osteotomy. Each approach for articular malunions has its potential risks and benefits. The true risks of articular malunion correction may not be fully known, because of the small number of cases in each presented series and the short follow-ups. Finger motion may be improved by correction of deformity alone, and may be further enhanced by tenolysis of adjacent adhesions. Capsulolysis may be helpful in instances of adjacent joint contracture. Despite improvement of finger motion in a majority of cases, some degree of remaining stiffness is common. Stiffness is almost always a residual of the original injury rather than a complication of corrective surgery, and serves to reinforce the fact that primary fracture reduction, stabilization, and rehabilitation are usually the best deterrents to malunion and consequent impairment. Much of the best available information has been gained from retrospective cohort or case study reports that may have inherent flaws in study design that limit their statistical validity and ability to detect trends. Flaws may include heterogeneity; investigator enthusiasm; and a lack of enrollment, prospective controlled randomization, blinding, confidence interval determinations, and follow-up. The statistical ability to determine trends in past reports may be compromised. Past reports provide important information and advances, but should be interpreted with some discretion. The pen may be mightier than the scalpel. In spite of encouraging reported results, phalangeal and articular osteotomies, in particular, remain daunting procedures for most hand surgeons. Prospective, controlled randomized studies maybe difficult to achieve in the clinical setting because of the time that would be necessary to secure adequate enrollments for statistical validity andthe occurrence of "dropouts" before completion of adequate follow-up. Meta-analysis is difficult because of variations in discriminators for patient selection and clinical outcomes. Although multicenter studies have their own inherent flaws, they may represent the best future option to add a higher level of study design and validity as compared with past studies. The incorporation of subjective patient outcome instruments into future studies might also provide valuable information. Investigators should review previous reports with a goal of improving study designs and scientific methodology, confirming or contradicting past results, or adding new information.

Assessment of fragment micromotion in distal femur fracture fixation with RSA

To assess fragment micromotion in three fracture fixation constructs 18 composite femur models were sectioned to create AO-C3 fractures and fixed using the Less Invasive Stabilization System (LISS), Dynamic Condylar Screw (DCS), or the Condylar Buttress Plate (CBP). Tantalum beads were attached to each fracture fragment. The constructs were tested for permanent deformation after cyclical loading (amplitude = 242.2N) and elastic deformation during static loading with 490.5N. Radiographs were taken before loading and then after unloading to determine permanent deformation or during loading to determine elastic deformation. We used RSA to quantify the six degrees of freedom interfragmentary maximum total motion, strain, and stress. For maximum total motion the CBP had more permanent deformation and two failures, whereas the LISS underwent the greatest elastic deformation. LISS and CBP had the highest strain conditions in the fracture gap and LISS had the greatest stress movements between fragments, all of which exceeded the upper limits for bone healing. LISS and CBP may not be indicated for comminuted fractures due to the high degree of flexibility of the LISS, resulting in high stress and strain conditions and susceptibility to catastrophic failure and high strain conditions with the CBP.

Operative treatment of femoral shaft fractures in children and adolescents

Although femoral shaft fractures constitute fewer than 2% of all fractures in children and adolescents, their treatment has produced many pieces of literature and years of controversy. Prevailing opinion has favored nonoperative and operative treatment, and a variety of techniques have been advocated to avoid complications such as nonunion, limb-length discrepancy, malalignment, osteonecrosis, and growth disturbance. Currently, operative methods of treatment generally are favored to allow early ambulation and shorter hospital stays and to avoid detrimental psychological and social effects often associated with prolonged nonoperative treatment, and to avoid complications. Options for operative fixation include external fixators, flexible and locked intramedullary nails, and compression and bridge plating. Although all of these can obtain good results in particular situations, there is no clear consensus of the indications for each. My choice for fixation of each fracture is based on consideration of a number of factors, including the age and size of the child, associated injuries, the location and pattern of the fracture, and the social situation of the child. In general, I prefer flexible nailing for younger children (6-10 years old) and locked nailing for adolescents at or near skeletal maturity. Bridge plating may be chosen for segmental, grossly comminuted fractures, whereas external fixation usually is reserved for severely comminuted or severe open fractures for which internal fixation is not appropriate.

Technical aspects of bridge plating for pediatric femur fractures

Bridge plating for the adult orthopedic trauma population has been increasing over the last few years. The technique, used in comminuted fractures, allows for stable internal fixation while reducing blood loss and the need for fracture site exposure. We have applied the technique of bridge plating for comminuted diaphyseal femur fractures in the pediatric trauma population due to the limitations of fracture treatment options in these patients. The use of 4.5-mm narrow low-contact dynamic compression plate plates with minimal exposure for plate entry and percutaneous screw placement has greatly facilitated the treatment of these fractures. The technique creates a stable mode of fixation while maximizing biologic fracture healing potential and also permits early patient mobilization.

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.

Principles of metacarpal and phalangeal fracture management: a review of rehabilitation concepts

Patients with common hand fractures are likely to present in a wide variety of outpatient orthopedic practices. Successful rehabilitation of hand fractures addresses the need to (1) maintain fracture stability for bone healing, (2) introduce soft tissue mobilization for soft tissue integrity, and (3) remodel any restrictive scar from injury or surgery. It is important to recognize the intimate relationship of these 3 tissues (bone, soft tissue, and scar) when treating hand fractures. Fracture terminology precisely defines fracture type, location, and management strategy for hand fractures. These terms are reviewed, with emphasis on their operational definitions, as they relate to the course of therapy. The progression of motion protocols is dependent on the type of fracture healing, either primary or secondary, which in turn is determined by the method of fracture fixation. Current closed- and open-fixation methods for metacarpal and phalangeal fractures are addressed for each fracture location. The potential soft tissue problems that are often associated with each type of fracture are explained, with preventative methods of splinting and treatment. A comprehensive literature review is provided to compare evidence for practice in managing the variety of fracture patterns associated with metacarpal and phalangeal fractures, following closed- and open-fixation techniques. Emphasis is placed on initial hand positioning to protect the fracture reduction, exercise to maintain or regain joint range of motion, and specific tendon-gliding exercises to prevent restrictive adhesions, all of which are necessary to assure return of function post fracture.

Two Techniques for Supplementing Interlocking Nail Repair of Fractures of the Humerus, Femur, and Tibia: Results in 12 Dogs and Cats

OBJECTIVE

To describe 2 devices for improving stabilization of inadequately stabilized interlocking nail (ILN) repairs of the humerus, tibia, and femur in dogs and cats.

STUDY DESIGN

Prospective study.

ANIMALS

Twelve client-owned dogs and cats.

METHODS

Two devices to further stabilize ILN repair of inadequately stabilized diaphyseal fractures were developed. Device 1 was an axial extension for the ILN that was connected to a conventional type I external skeletal fixator (ESF) with a short connecting bar. Device 2 had hybrid ILN bolt/ESF pins that were used to lock the ILN and serve as the pins for a type I ESF. Devices were used at the initial surgery when the stability of ILN repair was considered inadequate based on palpable fracture segment movement, insufficient medullary canal filling of the ILN at the fracture site, or when the ILN was used in a buttress mode. Outcome was obtained by recheck examinations, radiography, and telephone interview.

RESULTS

Device 1 was applicable to fractures of the humerus and femur, but was not used for fractures of the tibia because the ILN extension would have interfered with the stifle. No gross loosening of the ILN/ESF extension connection to the ILN occurred. Device 2 was easily placed and used in the humerus, femur, and tibia. Device 2 allowed removal of the ILN interlock to one or both main fracture segments non-invasively. Clinically, both devices added stability compared with ILN repair alone. Both devices facilitated controlled destabilization of the fracture repair as healing progressed. Complications of pin tract infection, and premature hybrid bolt/ESF pin loosening resulting in premature ESF removal each occurred in 1 patient. Four of 28 hybrid ILN/ESF pins were grossly loose at 4- or 6-week postoperative recheck examinations. Outcomes were excellent (9), good (1), fair (1), and poor (1).

CONCLUSIONS

Inadequately stabilized ILN repair of fractures can be stabilized by use of either device, both of which also permit controlled destabilization of the repair during healing. Device 2 can be used when non-invasive removal of the ILN interlock is desired during healing.

CLINICAL RELEVANCE

These 2 devices should be considered as alternative methods for stabilization of inadequately stabilized ILN repairs in dogs and cats, or when controlled destabilization of an ILN fracture repair is desired.

Locking compression plate loosening and plate breakage: a report of four cases

The Locking Compression Plate (LCP) system offers a number of advantages in fracture fixation combining angular stability through the use of locking screws with traditional fixation techniques. This makes the implant particularly suitable for use in poor bone stock and complex joint fractures, especially in the epimetaphyseal area. However, the system is complex, requiring careful attention to biomechanical principles, and a number of potential pitfalls need to be considered. These pitfalls are illustrated in the 4 cases described herein, in which treatment was unsuccessful due to implant breakage or loosening. In each case, treatment failure could be attributed to the choice of an inappropriate plate and/or fixation technique, rather than to the features of the Locking Compression Plate system itself. Such experiences highlight the importance of detailed understanding of the biomechanical principles of plate fixation as well as careful preoperative planning for the successful use of the Locking Compression Plate system.

Percutaneous plating of distal tibial fractures. Preliminary results in 21 patients

We describe the surgical technique and report the outcome after closed reduction and percutaneous plating in 21 closed extraarticular distal tibial fractures using titanium LC-DCP. A long plate was pushed subcutaneously through a small incision at the medial malleolus and fixed with screws through stab incisions. Fracture reduction was anatomical or nearly anatomical without angular displacement in 14 cases, and considered acceptable in four cases. Two patients were reoperated because of malreduction. Seventeen fractures healed within 6 months. There were two delayed unions, and two non-unions. There were two deep infections, both in diabetic patients. Follow-up by an independent observer at on average 14 (5-25) months showed various symptoms such as slightly reduced ankle mobility (9/20), reduced walking ability (11/20) or tenderness around the plate (11/20). No patient complained of knee symptoms related to the surgery. Operative treatment of closed distal tibial shaft fractures with a long titanium plate provided good anatomical results and allowed in most patients early weight-bearing. In patients with soft tissues in good condition and no risk factor for infection percutaneous plate osteosynthesis might become an attractive treatment option for fractures in the distal tibia.