A novel model of locking plate and locking spongious screw: a biomechanical in vitro comparison study with classical locking plate

BACKGROUND

Locking plates are commonly used for the fixation of comminuted, periprosthetic and osteoporotic bone fractures. These plates are secured to the bone with screws, creating a stable connection with fixed angle between the plate and the screws. In this biomechanical in vitro study, our aim is to evaluate and compare the novel locking plate-locking spongious screw model with FDA approved classical locking plate.

METHODS

Sawbone PCF-15 osteoporotic bone model was utilized to simulate osteoporotic bone conditions. Two screws were used to attach both the classical locking plate and the novel locking plate-locking spongious screw model to these bone models. The attachment strength of the screws to the bone blocks was measured by pull-out tests.

RESULTS

Novel locking plate-locking spongious screw model exhibited an 84.38% stronger attachment to the osteoporotic bone model compared to the current locking plate model.

CONCLUSIONS

In conclusion, one of the important problems in the locking plates which is the high Pull-out risk of the locking spongious screws can been resolved with our proposed new model and has a chance of having a better purchase especially in osteoporotic bones.

Comparisons of ankle arthrodesis with different internal fixation methods in the treatment of post-traumatic osteoarthritis

BACKGROUND

The aim of this study was to explore the clinical efficacy of ankle arthrodesis with different internal fixation methods in the treatment of post-traumatic osteoarthritis.

METHODS

We collected 85 patients with post-traumatic osteoarthritis who underwent different ankle arthrodesis between December 2015 and December 2020. The operation performance, complication rate, hindfoot alignment, talus tilt angle, visual analogue scale (VAS), and American Orthopedic Foot and Ankle Society (AOFAS) score were preoperatively and postoperatively evaluated.

RESULTS

In an anterior approach, the locking plate-fixation exhibited a similarity in operation time, incision length, postoperative drainage, bone fusion, hindfoot alignment, and talus tilt angle with fibula support compression screw-fixation, but it was better in increasing postoperative AOFAS. The locking plate-fixation in the anterior approach had lower operation time, incision length, and postoperative drainage than that in the lateral approach. In addition, the lateral locking plate combined with posterolateral compression screw fixation (LLPPCSF) presented shorter bone fusion time, higher AOFAS score, and lower complication rate than either plate- or screw-fixation alone.

CONCLUSION

Lateral locking plate fixation was better than fibula support compression screw fixation in relieving postoperative pain. Anterior locking plate fixation was more time-saving and less invasiveness than lateral locking plate fixation, but its application was limited in low degree of ankle deformation. LLPPCSF was the most effective in improving bone fusion and postoperative pain, considering an optimal option for the treatment of post-traumatic osteoarthritis.

Combining non-vascularized fibula and cancellous graft in the masquelet technique: A promising approach to distal femur compound fracture management with large defects

INTRODUCTION

Compound fractures of the distal femur with large defects pose a significant challenge in management, with several options available, including external fixators, bone grafting, the Masquelet-induced membrane technique, and free vascularized fibular grafts. The Masquelet-induced membrane technique involves placing a cement spacer in the defect to create a biologically active membrane. In the second stage, the gold standard for filling the defect is an autologous cancellous bone graft of 1-2 mm in size. This study aims to examine the effects of using a non-vascularized fibula as a support combined with a cancellous graft in the Masquelet technique for treating compound fractures of the distal femur.

METHODS

The study was conducted between December 2017 and December 2020 and included 11 patients who underwent the Masquelet technique. The procedure involved a lateral locked plate and an antibiotic-impregnated bone cement spacer, followed by a 20-30 mm longer ipsilateral fibula used as a strut graft. The remaining area was filled with cancellous bone from the iliac crest. The size of the defect, Time to the bony union, the average range of motion of the knee, and any complications are analysed. The final evaluation was done at 18 months using the Lower Extremity functional scale to assess functional outcomes.

RESULTS

The study included 11 patients (8 male and 3 female) with a mean age of 45.8 years. The average time to bony union was 6.6 months, and the average range of motion of the knee was 2.2° to 93.3 ° (0-110 °). No complications such as infection, non-union, or implant failure were observed.

CONCLUSION

The Masquelet Technique combined with a fibular strut graft is a feasible solution for complex distal femur fractures with bone loss. The non-vascularized fibula graft provides both structural support and reduces the amount of cancellous bone graft needed, which results in earlier weight bearing and improved functional outcomes.

Quality of life, functional and radiological outcomes of treatment of three-part and four-part proximal humerus fractures with locking plates and comparison in young versus older than 70 years: a retrospective cohort study

PURPOSE

Verify if the use of locking plates in displaced three- and four-part proximal humerus fractures has meant an improvement even in patients over 70 years of age.

MATERIAL AND METHODS

We performed surgery with locking plate fixation in 56 consecutive patients with three- and four-part proximal humerus fractures according to Neer's classification between 1/1/15 and 12/31/20 at our Hospital. Patient satisfaction, quality of life, functionality and radiological variables, as well as the comparison between patients older and younger than 70 years were the main outcomes. Likewise, factors and complications that may have influenced these variables were analyzed as secondary outcomes. The analysis of all these variables was performed after a minimum follow-up time of 24 months after surgery.

RESULTS

51 patients (92%) ended up satisfied or very satisfied according to the SF-36 test and with no disability or mild disability according to the DASH Score questionnaire. 46 patients (82%) obtained a satisfactory or excellent result according to the Neer scale modified by Cofield and 38 (68%) a good or excellent function according to the Constant Murley questionnaire. In 47 cases (84%) good radiological alignment was observed. Complications occurred in 20 patients (36%). The complications and the results of the SF-36, DASH Score, Neer scale modified by Cofield and Constant Murley tests depended on the radiological alignment (p = 0.009, p = 0.006, p = 0.025, p = 0.0008 and p = 0.0004). There were 37 patients younger than 70 years and 19 older than 70 years with no statistically significant differences when comparing the two groups.

CONCLUSIONS

This study demonstrates that satisfactory results can be obtained with osteosynthesis with locking plates in displaced proximal humerus fractures even in patients older than 70 years of age.

LEVEL OF EVIDENCE III

Retrospective Cohort, Treatment Study.

Resistance and Stress Analysis of 3D Plate and Locking Plate Fixation in Bilateral Sagittal Split Osteotomy: A Comparative Finite Element Study

Aim

This study evaluates the biomechanical properties of 3D plates and compares it with locking plates, in both set back and advancement models of bilateral sagittal split osteotomy (BSSO) using finite element model analysis.

Design

A stereolithography model of mandibular structure was imported to hypermesh to create 3D solid finite model. A BSSO was simulated on hemimandibular model and advancement and setback simulations were carried out for a distance of 4, 6, and 8 mm each. 3D plates for the right side and locking plates for the left side were simulated for fixation. Meshing of the model was carried out. After meshing, the model was imported to Ansys V18.1 for analysis of it. Forces simulating the masticatory muscles were applied on both sides. The values for stress and resistance in the screws and plates were measured and the lowest and highest deformation regions were estimated using von Mises analysis.

Results

The results suggest that the tension and resistance as measured through were better distributed in 3D plates when compared with that of locking plates; the stress concentration was shown to be higher in the locking plates and deformation resistance was greater in 3D plates.

Conclusion

The application of 3D plating system has found its place in the field of maxillofacial trauma. However, its application in the field of orthognathic surgery is yet to be explored and this study encourages us to conduct in vivo studies.

Current standard of care for distal femur fractures in Germany and Switzerland

BACKGROUND

Distal femur fractures occur with an incidence of 4.5/100,000 and show a prevalence of 0.4%. Causes include low-impact trauma in older patients and high-impact trauma in younger patients without pre-existing medical conditions. The aim of this study was to perform a comprehensive evaluation of trauma mechanisms, trauma-promoting factors, comorbidities, medication history and type of surgical care to provide an overview of the causes of injury and the most appropriate therapeutic approach.

METHODS

In this multicenter cohort study a retrospective analysis of 229 patients who sustained a distal femur fracture between January 2011 and December 2020 was performed. Individual fracture patterns, fracture predisposing factors, concomitant disease profiles, medication history, treatment strategy and associated complications were analyzed.

RESULTS

229 patients were included in the retrospective analysis. A total of 113-type 33 A, 50-type 33 B and 66-type 33 C fractures were diagnosed, of whom 92% received a lateral locking plate osteosynthesis. There was a complication in 14.4% of all cases, of which 6.1% were attributable to infection. Significant risk factors for developing a complication were an increased BMI (29.9 ± 8.5 kg/m2; p = 0.04), fracture displacement of over half a shaft width (p < 0.001) and AOC fractures (p < 0,016), specifically C2 fractures (p < 0,008).

CONCLUSION

In this multicenter retrospective cohort study, lateral locking plate osteosynthesis was the method of choice and was selected in over 90% of cases, regardless of the fracture classification and risk factors. A complication rate of 14.4% emphasizes the necessary analysis of patient- and care-specific risk factors and a resulting adjustment of the therapy strategy. An increased BMI (29.9 ± 8.5 kg/m2; p = 0.04), fracture displacement of over half a shaft width (p < 0.001) and AOC fractures (p < 0,016), specifically C2 fractures (p < 0,008) increase the risk of developing a complication and should prompt an early switch to a treatment strategy that provides more stability.

Locking conical coupling plates in small animal orthopedics: A review

Conical coupling locking plates (CCP) have become an interesting alternative in veterinary orthopedics and traumatology. Available data in this regard, however, must be interpreted with caution, and several studies are still required to reach definitive conclusions on the clinical use of these implants. In this context, this review aims to discuss CCP applications and mechanical aspects in small animals and summarize in vivo, in vitro and ex vivo study results.

Talo-navicular and calcaneo-cuboid fusion with PEEK H-pode™ vs. Titanium Maxlock™ locking plates: Comparison of functional and radiographic outcomes

BACKGROUND

Locking plates are increasingly used to achieve hindfoot fusion. The objective of this study was to compare hindfoot fusion outcomes with the PEEK H-pode™ (Biotech™) locking plate and the titanium Maxlock™ (Tornier-Wright™) locking plate.

HYPOTHESIS

A polyetheretherketone (PEEK) H-pode™ locking plate provides similar fusion rates to a titanium Maxlock™ locking plate for talo-navicular and calcaneo-cuboid arthrodesis.

METHODS

We conducted a retrospective comparative study in 39 patients (including 21 [54%] with pes planovalgus and 11 [28%] with neurological equinovarus deformities) who underwent talo-navicular and/or calcaneo-cuboid fusion, usually combined with subtalar fusion. The first 17 patients (January 2014-February 2016) were managed with Maxlock™ locking plates and the next 22 patients (March 2016-August 2018) with H-pode™ locking plates. These two cohorts of consecutive patients were comparable regarding age, sex distribution, body mass index, and comorbidities. At last follow-up more than 1year after surgery, we compared functional scores, pain intensity, and fusion assessed by radiographs and computed tomography (CT) (threshold set at 33%).

RESULTS

Mean follow-up was 42months (range: 34-63months) in the Maxlock™ group and 25months (range: 12-36months) in the H-pode™ group. At last follow-up, the two groups were not significantly different for the mean values of the American Orthopedic Foot & Ankle Society score, European Foot & Ankle Society score, and visual analogue scale pain score. Neither were the two groups significantly different for talo-navicular and calcaneo-cuboid fusion by CT. In the Maxlock™ group, we found non-significant trends towards a higher proportion of patients with talo-navicular nonunion (18% vs. 5% in the H-pode™ group) and weaker talo-navicular fusion in patients with pes planovalgus (60.8% vs. 82.0%, respectively). Radiographic results overestimated the fusion rates.

DISCUSSION

Talo-navicular and calcaneo-cuboid fusion was not significantly different with H-pode™ and Maxlock™ locking plates. CT was more accurate than standard radiography to assess fusion. These results underline the usefulness of PEEK locking plates for talo-navicular and calcaneo-cuboid fusion; moreover, the radiolucency of PEEK facilitates the interpretation of radiographs.

LEVEL OF EVIDENCE

IV.

Outcomes following fracture fixation with the Equinoxe® proximal humerus plate: an improvement over PHILOS®?

INTRODUCTION

The purpose of this study is to compare patient outcomes between the Equinoxe® (Exactech, Gainesville, Fla) proximal humerus locking plate and the PHILOS® (Synthes, Paoli, PA) proximal humerus locking plate.

METHODS

Two hundred and seventy-one patients with a displaced proximal humerus fracture presented to our academic medical center between February 2003 and October 2020. Functional outcomes assessed included the Disabilities of the Arm, Shoulder, and Hand questionnaire and shoulder range of motion. Radiographs were utilized to determine fracture healing and development of posttraumatic osteoarthritis or osteonecrosis.

RESULTS

Overall, 108 Equinoxe® and 87 PHILOS® patients treated by a single surgeon with complete clinical, functional, and radiographic follow-up were included in the study. Demographics were similar between groups. One hundred and eight Equinoxe® patients healed at a mean time to union by 3.7 ± 2.2 months, and 86 PHILOS® patients healed (p = 0.24) by 4.1 ± 2.3 months after surgery (p = 0.31). Shoulder external rotation was greater in Equinoxe® patients by 7 degrees (p = 0.044), and forward elevation was greater by 16 degrees (p = 0.005) at one-year follow-up. DASH scores were similar between patients at the 3-, 6-, and 12-month follow-up (p = 0.86, p = 0.77, p = 0.64). Fewer Equinoxe® patients experienced complications (p = 0.043).

CONCLUSION

Fixation of a proximal humerus fracture can safely be performed with both Equinoxe® and PHILOS® proximal humerus locking plates. Patients fixed with Equinoxe® plates achieved a slightly greater degree of external rotation, forward elevation, and experienced fewer complications. This difference may be due to surgeon experience rather than the implant itself.

Locking versus non-locking plates in fixation of extra-articular distal humerus fracture: a randomized controlled study

INTRODUCTION

Studies have shown that the use of nonlocking (reconstruction) plates in fixing distal humerus fractures may not yield stable fixation which therefore requires long immobilization and suboptimal functional results. There are reports showing that locking plates are biomechanically superior to nonlocking plates. The aim of this study was to compare elbow functional outcomes between locking and nonlocking plates in fixation of distal humerus fractures.

METHODS

A single-centre, randomized control study was conducted at an academic level 1 trauma centre. A total of 60 patients with type 13-A fracture (AO/OTA classification) were randomized into two equal groups, locking plates group, and nonlocking plates group. The primary outcome measure was the Mayo elbow performance score (MEPS) at one year. Secondary outcomes measures were elbow flexion/extension arc, union, operative time, and complications (e.g., infection, heterotrophic ossification).

RESULTS

The Mayo Elbow Performance Score (MEPS) at one year was 88 ± 10.1 in locking plates group and 75.8 ± 12.8 in nonlocking plates group. The difference was found to be statically significant (P value = 0.01). Elbow flexion/extension arc of motion at one year was 116° ± 15° in locking plates group and 113° ± 28° in nonlocking plates. The difference was not found to be statistically significant (P value = 0.17).

CONCLUSION

Both implants yield similar results, with locking plates showing slightly better clinical scores.

Comparison of optimal screw configurations in two locking plate systems for proximal humerus fixation - a finite element analysis study

BACKGROUND

Management of proximal humerus fractures is challenging, especially in elderly. Locking plating is a common surgical treatment option. The Proximal Humerus Internal Locking System (plate-A) has shown to lower complication rates compared to conventional plates, but is associated with impingement risk, which could be avoided using Peri-articular Proximal Humerus Plate (plate-B). Nevertheless, biomechanical performance and optimal screw configuration of plate-B is unknown. The aim of this study was to evaluate different screw configurations of plate-B and compare with plate-A using finite element analyses.

METHODS

Twenty-six proximal humerus models were osteotomised to create unstable three-part fractures, fixed with either of the two plates, and tested under three anatomical loading conditions using a previous established and validated finite element simulation framework. Various clinically relevant screw configurations were investigated for both plates and compared based on the predicted peri-implant bone strain, being a validated surrogate of cyclic cut-out failure.

FINDINGS

Besides increasing the number of screws, the placement of the posterior screws in combination with the calcar screw in the plate-B significantly decreased the predicted failure risk. Generally, plate-A had a lower predicted failure risk than plate-B.

INTERPRETATION

The posterior and calcar screws may be prioritized in plate-B. Compared to plate-A, the more distal positioning, less purchase in the posterior aspect and a smaller screw spread due to not fitting of the most distal calcar screw in most investigated subjects led to a significantly higher predicted failure risk for most plate-B configurations. The findings of the simulations study require clinical corroboration.

Corrective osteotomy after malunited distal radius fractures

Posttraumatic malunion or secondary dislocation can cause wrist joint incongruency. Uncorrected malalignment increases the risk of secondary degenerative changes and chronic pain. Therefore, early correction using the available fixed-angle devices, cancellous bone grafting only becomes necessary in larger bony defects. Premounting the plate through a palmar approach with regard to the desired correction angles leads to predictable results by precise correction. In case of posttraumatic growth arrest with larger discrepancy of the radius and the ulna, a two-staged procedure is advisable.

Management of periprosthetic fracture following total knee arthroplasty- a retrospective study to decide when to fix or when to revise?

PURPOSE

Periprosthetic fractures around total knee arthroplasty are relatively rare complication comprises to 0.3-2.5%. But these injuries are often complex and challenging for the surgeons due to ageing population in conjunction with severe osteoporosis. The management option varies from conservative to internal fixation or revision surgery. Thus this study was conducted to analyze the results of various methods of treatment of periprosthetic fractures following TKA and to form the optimal treatment guidelines for fixation or revision.

MATERIAL AND METHODS

51 cases diagnosed with periprosthetic fracture were enrolled and underwent surgical intervention. Type of primary prosthesis, interval between TKA and periprosthetic fracture, type of fracture, prosthesis stability and mode of fixation of fracture, any revision surgery and complication were noted.

RESULTS

The mean age of all patients was 65.89 years. The mean interval between the index surgery and periprosthetic fracture was 6 years (Range 2 months to 10 years) in male and 18.5 months (Range 4 days to 7 years) in female. 44 (86%) fractures were femoral, 4 (8%) fractures were tibial and 3 (6%) fractures were of patella. The mean knee society score (KSS) & oxford knee score (OKS) were found to be good for revision group as compared to the fixation group at final follow up.

CONCLUSION

In presence of poor bone stock, far distal fracture configuration, comminution, severe osteoporosis, difficulty in achieving stability with plates & old age-revision TKA is a viable option with stemmed components.

A probabilistic-based approach for computational simulation of bone fracture healing

BACKGROUND AND OBJECTIVE

It is widely known that bone fracture healing is affected by mechanical factors such as fracture geometry, fixation configuration and post-operative weight bearing loading. However, there are several uncertainties associated with the magnitude of the mechanical factors affecting bone healing as it is challenging to adjust and control them in clinical practice. The current bone fracture healing investigations mainly adopt a deterministic approach for identifying the optimal mechanical conditions for a favourable bone healing outcome. However, a probabilistic approach should be used in the analysis to incorporate such uncertainties for prediction of bone healing.

METHODS

In this study we developed a probabilistic-based computational model to predict the probability of delayed healing or non-union under different fracture treatment mechanical conditions for fractures stabilised by locking plates.

RESULTS

The results show that there is a strong positive linear correlation between the mechanical stimulations (S) in the fracture gap and the magnitude of weight bearing, the bone-plate distance (BPD) and the plate working length (WL), whereas the fracture gap size has a highly negative and nonlinear correlation with S. While the results show that fracture mechanical microenvironment is more sensitive to the uncertainties in WL compared to BPD, the uncertainty associated with the magnitude of WL is very low and can be resulted from implant manufacturing tolerance. However, there is a high uncertainty associated with the magnitude of BPD as it cannot be accurately adjusted during the surgery. The results show that the tissue differentiation at the far cortex of fracture gap is more sensitive to the variation of BPD compared with that at the near cortex. The probability of delayed healing (fibrous tissue formation) at far cortex is increased from 0% to 40% when coefficient of variation (COV) of BPD rises from 0.1 to 0.9 (for average BPD = 2 mm, WL = 65 mm, fracture gap size = 3 mm and Weight bearing = 150 N). Further, both near and far cortex of fracture site are sensitive to the variation in weight bearing loading.

CONCLUSIONS

The developed probabilistic model may lead to useful guidelines that could help orthopaedic surgeons identify how reliable a specific fracture treatment strategy is.

The risk of loosening of extramedullary fracture fixation devices

Extramedullary devices that use screws, pins or wires are used extensively to treat fractures in normal and diseased bone. A common failure mode is implant loosening at the bone-screw/pin/wire interface before fracture healing occurs. This review first considers the fundamental mechanics of the bone-fixator construct with focus on interfacial strains that result in loosening. It then evaluates the time-independent and time-dependent material models of bone that have been used to simulate and predict loosening. It is shown that the recently developed time-dependent models are capable of predicting loosening due to cyclic loads in bone of varying quality.

Tension band wiring versus locking plate fixation for simple, two-part Mayo 2A olecranon fractures: a comparison of post-operative outcomes, complications, reoperations and economics

PURPOSE

Simple displaced transverse olecranon fractures are traditionally managed operatively with a tension band wire device (TBW). We compared clinical outcomes, morbidity and the cost of treatment of TBW versus pre-countered low-profile locking plates for the treatment of Mayo 2A fractures.

PATIENT AND METHODS

All olecranon fractures admitted to our unit between 2008 and 2014 were identified (n = 129). Patient notes and radiographs were studied from presentation to final follow-up. Patient outcomes were recorded using the QuickDASH (Disabilities of Arm, Shoulder and Hand) score. Patient demographics and nature of complications were recorded as were the rate and nature of any repeat operation.

RESULTS

Eighty-nine patients had Mayo 2A fractures (69%). Sixty-four underwent TBW (n = 48) or locking plate fixation (n = 16). The mean ages of both groups were similar at 57 (15-93) and 60 (22-80), respectively. In the TBW group, the mean post-injury QuickDASH was 12.9, compared with 15.0 for the locking plate group. There was no statistically significant difference between the outcomes for either group. Nineteen of the 48 TBW patients had complications (39.6%). Sixteen of the 48 TBW patients had reoperations (33.3%). In particular, we would highlight that 13 (27.1%) of patients treated with TBW underwent subsequent removal of metalwork for hardware irritation. There were no complications and or reoperations in the 16 patients who received locking plate fixation. Both complication and reoperation rates were statistically significantly different. Despite being initially more expensive, when the cost of reoperation for TBW group was included, locking plates were found to be on average £236.33 less per patient than for TBW.

CONCLUSIONS

We suggest that locking plates are superior to TBW concerning post-operative morbidity, reoperation rate and cost for Mayo 2A fractures in contrast to previous articles.

LEVEL OF EVIDENCE

Therapeutic study, III.

A comparison of complication rates between locking and non-locking plates in distal fibular fractures

BACKGROUND

Locking compression plates have become increasingly popular in orthopaedic surgery. However, the gold standard of treatment for distal fibular fractures remains fixation with a non-locking one-third tubular plate. It has been reported that locking plates in distal fibular fractures are associated with an increased complication rate.

HYPOTHESIS

The objective of this study is to assess the complication rates of locking versus non-locking plates in patients who underwent surgical fixation of distal fibular fractures.

MATERIALS & METHODS

A retrospective analysis of closed distal fibular fractures that underwent surgical repair over a 2-year period with either a locking or non-locking plate was undertaken, analysing the groups for both wound and overall postoperative complications.

RESULTS

A total of 160 patients were treated over 2 years, of which 129 and 31 patients were treated with non-locking and locking plates respectively. There was no significant difference between the non-locking and locking plates overall complication rates (13.5% versus 15.4%, p=0.76) or wound complication rates (3.97% versus 3.85%, p=1.00).

DISCUSSION

Distal fibular fractures managed with locking plates do not have a higher complication rate in comparison to those managed with non-locking plates.

LEVEL OF EVIDENCE

III (case control study).

Comparing case-control study for treatment of proximal tibia fractures with a complete metaphyseal component in two centers with different distinct strategies: fixation with Ilizarov frame or locking plates

Background

The purpose of this study was to compare two methods of stabilization for proximal tibia fractures (AO 41) with a complete metaphyseal component, external fixation with the Ilizarov wire frame, and internal fixation with locking plates.

Methods

Patients from two level 1 trauma centers treated between 2009 and 2015 were included in a retrospective comparing cohort study. The first center stabilized the non-pathological, proximal tibia fractures exclusively with external fixation and the second with internal plating. Combined clinically and radiologically evaluated, bone healing was the primary outcome. The secondary outcomes included complications, range of motion (ROM) and axial alignment of the knee, the reoperation rate within 6 months, heterotopic ossifications (HTO), and signs of posttraumatic osteoarthritis (PTOA). A logistic regression analysis corrected for uneven distributed parameters.

Results

The 62 patients treated with Ilizarov frame and the 68 patients treated with plate fixation were comparable regarding epidemiological parameters, injury characteristics, and comorbidity except for injury severity score (ISS) and smoking behavior. The time of healing was shorter in the group undergoing plate fixation (p = 0.041); however, the incidence of non-unions was equal. Furthermore, there was no difference regarding the rate of deep infections, thrombosis, alignment, reoperations, PTOA, and ROM. Heterotopic ossifications were more prevalent following plate fixation (13.2 vs 1.6%, p = .013). External fixation was associated with a higher rate of superficial infections (40.4 vs 2.9%, p = .000). The initial displacement, the incidence of deep infections, and the classification significantly influenced the incidence of non-unions in both groups (p < 0.02).

Conclusions

Fixation of proximal tibia fractures with plates resulted in a slightly shorter healing time compared to Ilizarov frame stabilization. Furthermore, the complication profiles differ with more heterotopic ossifications and less superficial infections following internal plating.

Trial registration

DRKS, DRKS00013275, Registered 11/2/2017, Retrospectively registered.

Electronic supplementary material

The online version of this article (10.1186/s13018-018-0792-3) contains supplementary material, which is available to authorized users.

Biomechanical analysis of plate systems for proximal humerus fractures: a systematic literature review

BACKGROUND

Proximal humerus fractures are the third most common in the human body but their management remains controversial. Open reduction and internal fixation with plates is one of the leading modes of operative treatment for these fractures. The development of technologies and techniques for these plates, during the recent decades, promise a bright future for their clinical use. A comprehensive review of in vitro biomechanical studies is needed for the comparison of plates' mechanical performance and the testing methodologies. This will not only guide clinicians with plate selection but also with the design of future in vitro biomechanical studies. This review was aimed to systematically categorise and review the in vitro biomechanical studies of these plates based on their protocols and discuss their results. The technologies and techniques investigated in these studies were categorised and compared to reach a census where possible.

METHODS AND RESULTS

Web of Science and Scopus database search yielded 62 studies. Out of these, 51 performed axial loading, torsion, bending and/or combined bending and axial loading while 11 simulated complex glenohumeral movements by using tendons. Loading conditions and set-up, failure criteria and performance parameters, as well as results for each study, were reviewed. Only two studies tested four-part fracture model while the rest investigated two- and three-part fractures. In ten studies, synthetic humeri were tested instead of cadaveric ones. In addition to load-displacement data, three-dimensional motion analysis systems, digital image correlation and acoustic emission testing have been used for measurement.

CONCLUSIONS

Overall, PHILOS was the most tested plate and locking plates demonstrated better mechanical performance than non-locking ones. Conflicting results have been published for their comparison with non-locking blade plates and polyaxial locking screws. Augmentation with cement [calcium phosphate or poly(methyl methacrylate)] or allografts (fibular and femoral head) was found to improve bone-plate constructs' mechanical performance. Controversy still lies over the use of rigid and semi-rigid implants and the insertion of inferomedial screws for calcar region support. This review will guide the design of in vitro and in silico biomechanical tests and also supplement the study of clinical literature.

Calcar screw position in proximal humerus fracture fixation: Don't miss high!

INTRODUCTION

In locked plate fixation of proximal humerus fractures, the calcar is an important anchor point for screws providing much-needed medial column support. Most locking plate implants utilize a fixed-trajectory locking screw to achieve this goal. Consequently, adjustments of plate location to account for patient-specific anatomy may result in a screw position outside of the calcar. To date, little is known about the consequences of "missing" the calcar during plate positioning. This study sought to characterize the biomechanics associated with proximal and distal placement of locking plates in a two-part fracture model.

MATERIALS AND METHODS

This experiment was performed twice, first with elderly cadaveric specimens and again with osteoporotic sawbones. Two-part fractures were simulated and specimens were divided to represent proximal, neutral, and distal plate placements. Non-destructive torsional and axial compression tests were performed prior to an axial fatigue test and a ramp to failure. Torsional stiffness, axial stiffness, humeral head displacement and stiffness during fatigue testing, and ultimate load were compared between groups.

RESULTS

Cadavers: Proximal implant placement led to trends of decreased mechanical properties, but there were no significant differences found between groups. Sawbones: Distal placement increased torsional stiffness in both directions (p = 0.003, p = 0.034) and axial stiffness (p = 0.018) when compared to proximal placement. Distal placement also increased torsional stiffness in external rotation (p = 0.020), increased axial stiffness (p = 0.024), decreased humeral head displacement during fatigue testing, and increased stiffness during fatigue testing when compared to neutral placement.

DISCUSSION

The distal and neutral groups had similar mechanical properties in many cadaveric comparisons while the proximal group trended towards decreased construct stiffness.

RESULTS

from the Sawbones model were more definitive and provided further evidence that proximal calcar screw placements are undesirable and distal implant placement may provide improved construct stability.

CONCLUSION

Successful proximal humerus fracture reconstruction is inherent upon anatomic fracture reduction coupled with medial column support. Results from this experiment suggest that missing the calcar proximally is deleterious to fixation strength, while it is safe, and perhaps even desirable, to aim slightly distal to the intended target.

Management of comminuted fractures of the distal humerus: clinical outcome after primary external fixation versus immediate fixation with locking plates

OBJECTIVES

The surgical treatment of comminuted fractures of the distal humerus remains a challenging problem. The aim of the present study was to compare the clinical outcomes of primary external fixation with second-staged open reduction and internal fixation (ORIF) and initial definitive internal fixation in surgically treated patients with comminuted distal humerus fractures.

DESIGN

Retrospective comparative study.

SETTING

Level one trauma center.

PATIENTS

A total of 24 patients (median age 52 years; range 14-84 years) were included: 15 patients were treated with initial definitive internal fixation with pre-contoured locking compression plates (group A), and 9 patients underwent surgical treatment with primary external fixation and second-staged ORIF (group B). Only patients with C3 fractures according to the AO classification were included in the study.

MAIN OUTCOME MEASUREMENT

Disability of the Arm, Shoulder and Hand (DASH) and Mayo Elbow Performance Score (MEPS).

INTERVENTION

External fixation internal fixation with locking plates.

RESULTS

The median follow-up was 37 months for both groups. There was a significantly higher median elbow extension deficit in group B (39°) compared to group A (17°) (p = 0.048). The mean DASH score in group A was 14 and 12.5 in group B. MEPS showed that more patients in group A achieved excellent results; however, there was no significant difference compared to group B.

CONCLUSIONS

Primary external fixation with second-staged ORIF demonstrated a higher complication rate and significantly greater loss of extension compared with initial definitive internal fixation. Thus, the use of primary external fixation in cases of comminuted distal humerus fractures appears to have a negative influence on the patient outcomes.

LEVEL OF EVIDENCE

Therapeutic level III.

Locking plates versus intramedullary nails in the management of displaced proximal humeral fractures: a systematic review and meta-analysis

PURPOSE

To compare the clinical outcome and complications of locking plates versus intramedullary nails in patients with displaced proximal humeral fractures. Our hypothesis was that there would be no difference between these two implants with regard to clinical outcome and complications.

METHODS

We performed a systemic review of PubMed, EMBASE, Clinical Trials Registry, Cochrane Central Register of Controlled Trials and Google Scholar to identify all relevant randomized controlled trials, prospective and retrospective comparative studies on April 26, 2017. The studies of locking plates compared to intramedullary nails in patients with displaced proximal humeral fractures were included. We conducted a meta-analysis of shoulder functional scores, range of motion, pain scores, and complications.

RESULTS

This meta-analysis included 13 comparative studies with 958 patients (529 in the locking plate group and 429 in the intramedullary nail group). A significantly greater external rotation (MD = 9.67; 95% CI, 4.22-15.12; P = 0.0005) and a significantly higher penetration rate (RR = 1.75; 95% CI, 1.11-2.77; P = 0.02) were observed in the locking plate group compared with the intramedullary nail group. Constant-Murley scores, DASH scores and total complication rate were comparable between the two groups. Moreover, there were no significant differences in forward elevation, VAS scores, and other complications.

CONCLUSIONS

Current evidence indicates that locking plates and intramedullary nails have similar performance in terms of the functional scores and total complication rate. No superior treatment was suggested between locking plates and intramedullary nails for displaced proximal humeral fractures.

Comminuted olecranon fractures: biomechanical testing of locked versus minifragment non-locked plate fixation

INTRODUCTION

Open reduction and internal fixation has long been accepted as optimal treatment for displaced olecranon fractures based on poor results seen with conservative management. With the presence of comminution, tension-band wiring constructs are contraindicated due to tendency to compress through fragments, thereby shortening the articular segment. Therefore, plate fixation is typically employed. Our hypothesis was that in a comminuted fracture model, 2.7 mm reconstruction plating without locking screws will perform equally to 3.5 mm locked plating in terms of fracture displacement and rotation (shear).

MATERIALS AND METHODS

A three-part comminuted olecranon fracture pattern was created in nine matched pairs of cadaveric specimen using an oscillating saw in standardized, reproducible fashion. Each matched pair was then randomized to receive either 2.7 mm reconstruction plating or 3.5 mm proximal ulna locked plating. Random allocation software was used to assign the 2.7 mm plate construct to either the right or left side of each pair with the contralateral receiving the 3.5 mm plate construct. Specimens were cyclically loaded simulating passive range of motion exercises commonly performed during rehabilitation. Displacement and rotation in relation to the long axis of the ulna were measured through motion capture. Fragment gapping and rotation was quantified following 100 cycles at 10 N and again following 100 cycles at 500 N.

RESULTS

No significant differences were detected between the 2.7 and 3.5 mm plates in fracture rotation or gapping following loads at 10 N (0.5° and 0.7°; 0.6 and 1.2 mm; respectively; p > 0.05) or 500 N (2.3° and 1.6°; 3.8 and 3.1 mm; respectively; p > 0.05) loading. Fragment rotation and gapping were positively correlated within each plate construct (R ² > 0.445; p < 0.05).

CONCLUSIONS

2.7 mm plating is an alternative to 3.5 mm locked plating with decreased plate prominence without significantly sacrificing displacement and rotational control. This is beneficial in fracture patterns where the traditional dorsal plating does not offer optimal screw trajectory.

Comparison of 2 mm single locking miniplates versus 2 mm two non-locking miniplates in symphysis and parasymphysis fracture of mandible

INTRODUCTION

The purpose of this study is to compare the efficacy of single 2 mm locking miniplates versus two 2 mm non-locking (conventional) miniplates in symphysis and parasymphysis fracture of mandible.

METHOD

This present study included 40 patients of maxillofacial trauma having mandibular symphysis/parasymphysis fractures in which open reduction and internal fixation is indicated. Patients were selected according to the inclusion criteria and divided into two groups, i.e. Group 1: consisted of 20 patients, requiring open reduction and internal fixation with 2 mm two non-locking titanium plate and Group 2: consisted of 20 patients, requiring open reduction and internal fixation with 2.0 mm single ultra-locking titanium plate. Fracture was then stabilized and postoperative clinical examination was carried out on 3rd day, 1st, 2nd, 4th, and 8th week.

RESULT

Results of this study suggested that the use of single 2.0 mm locking miniplate could be a viable option instead of using two miniplates in anterior mandibular fracture as advocated by Champy, as it provides equally good outcome along with placement of lesser implant material.

DISCUSSION

Single locking miniplates give the advantage of equally good stability and early restoration of function with almost similar results as seen in osteosynthesis with two miniplates. It was also found that less precision was required in plate adaptation when using single locking miniplate. This study suggests that there is not much difference in surgical outcome with the use of either single locking miniplate or two conventional miniplates in anterior mandibular region.

Hertel 7 fracture of the humeral head. Can two different fixation systems (Diphos/PHP) lead to different outcomes? A retrospective study

OBJECTIVE

To compare clinical outcomes and complication rates in the medium-to-long-term follow-up of Hertel 7 humeral head fractures treated with two different locking plates.

MATERIALS AND METHODS

A total of 52 patients with type 7 humeral head fracture (in accordance with Hertel classification) were enrolled retrospectively: 24 patients [4 male, 20 female; mean age (standard deviation [SD]): 68.9 (5.8) years] were treated with Diphos H plate (Group A) and 28 patients [6 male, 22 female; mean age (SD): 61.0 (7.5) years] with Proximal Humeral Plate (PHP; Group B). The mean follow-up periods were 25.6 and 18.9 months, respectively. Functional outcomes were assessed using the Constant score and Disabilities of the Arm, Shoulder and Hand (DASH) score; X-ray evaluation was also performed and complications were recorded.

RESULTS

The mean Constant score in the Diphos and PHP groups at follow-up were 75.6 (SD 13.4) and 78.9 (SD 12.8), respectively (p>0.05). The DASH score was similar in both groups (Diphos: 18.6, range 0-51.5; PHP: 16.8, range 0-47.8) (p>0.05). In our series, 9.6% of patients had complications; these included a case of aseptic non-union and a case of avascular necrosis of the humeral head in each group, and a secondary screw perforation in a patient treated with Diphos.

CONCLUSIONS

In patients with Hertel 7 proximal humeral fractures, Diphos and PHP lead to similar satisfactory functional outcomes and are associated with low complication rates; this confirms that both are useful implants for the treatment of this pattern of fracture.

The biomechanical cost of variable angle locking screws

INTRODUCTION

Variable angle (VA) locking plates in fracture fixation surgery allow screws to be fastened to the plate within a conical "locus of vectors" in order to avoid existing prostheses, joint surfaces, or poor quality bone. Clinical failures of VA constructs in which screws have rotated at the plate/screw interface have been reported raising the concern that there may be a biomechanical cost for the increased flexibility that VA provides. The objective of this study was to test the mechanical properties of one commonly used VA locking mechanism with screws placed in both nominal and off-axis trajectories and compare these against the standard locking mechanism.

METHODS

VA locking screws were inserted into plates for distal femur fractures (VA Curved Condylar) at various angles (0° to 15° away from perpendicular). A control group of standard locking screws/plates was also tested. Maximum moment at the screw/plate interface and moment at two reference displacements were determined.

RESULTS

VA screws locked perpendicular to the plate provided the greatest maximum moment and moment at the reference displacements when using the VA system, and demonstrated lower moments compared to standard locking screws/plates (p<0.001). Based on linear regression, there was an average decrease of approximately 0.4 Nm screw-plate interface strength for every 1° increase in screw-plate angle (p<0.001). Decreases (p<0.05) were discovered in both maximum moment and moment at the reference displacements for screws locked at 5° relative to those locked at 0°, 10° relative to 0°, and 15° relative to 10°.

DISCUSSION

Standard locking systems provided greater resistance to rotational failure at the screw/plate interface than variable angle locking systems. Variable angle systems provided the greatest resistance to rotation when the screw was inserted perpendicular to the plate. As the off-axis angle increased, the resistance to rotation at the screw/plate interface decreased almost linearly. It is unknown if these differences are clinically significant in an actual fracture construct, but recent reported failures in the distal femur suggest that they might be.

CONCLUSION

Surgeons should weigh the risks and benefits of VA systems and attempt to minimize the off-axis angle magnitude when VA systems are selected.

What's new in the management of complex tibial plateau fractures?

The management of complex tibial plateau fractures is ever evolving. The severity of the injury to the surrounding soft tissues influences the timing and the method of fixation. Minimal invasive techniques continue to dominate our philosophy of reduction and reconstruction whereas augmentation of depressed intra-articular fragments remains an accepted strategy to maintain reduction and prevent secondary collapse. Locking plates, conventional plates and fine wire fixators all have been used successfully with satisfactory outcomes. In this article we report on the latest advances made in the management of these complex injuries.

Bite Force Evaluation of Conventional Plating System Versus Locking Plating System for Mandibular Fracture

AIMS AND OBJECTIVES

To compare and evaluate the variation in recorded bite forces in patients with mandibular fractures undergoing open reduction and rigid internal fixation using standard 2.0 versus 2.0 mm locking miniplates.

MATERIALS AND METHODS

A prospective randomized study was conducted for the treatment of mandibular fractures. Twenty adult patients with 31 mandibular fractures requiring an open reduction and internal fixation were included in the study. The sample was divided into two groups depending upon whether the patients received 2.0 mm non-locking (standard) or 2.0 mm locking miniplates for rigid fixation respectively. Bite force was evaluated at 1st, 3rd and 6th week after the open reduction and rigid fixation using miniplates.

RESULTS

A statistically significant difference was not found in the clinical parameters such as pain, swelling, infection, paresthesia, hardware failure, and mobility between the fracture segments. The results showed that amongst locking vs non-locking miniplates, the former showed a greater bite force enhancement when compared to baseline values(post-trauma).A comparison between 2nd day post-operative vs 6th week post-operative values showed a significant increase in bite force in Group 1 (non-locking) (p < 0.05) whereas the values Were highly significant (p < 0.001) in Group 2 (locking Plate).

CONCLUSION

The findings were suggestive that the efficacy of locking miniplates plate in mandibular fracture was superior in terms of bearing the masticatory loads during osteosynthesis of the fracture. However, the clinical results were almost similar to those seen with non-locking miniplate osteosynthesis.

The outcome of Polyax Locked Plating System for fixation distal femoral non-implant related and periprosthetic fractures

The objective of this study was to report on the safety, efficacy and clinical outcomes of the Polyax Locked Plating System (Biomet, Warsaw, IN, USA) in the management of acute (non-implant related and periprosthetic) distal femoral fractures. We retrospectively reviewed 71 patients with 73 distal femoral fractures. Thirty-three of the included fractures occurred around previously placed implants. The average patients' age was 67 years (range 18-98). There were 7 early postoperative complications (9.5%) including one deep surgical site infection, 2 pulmonary embolisms and 4 urinary or respiratory infections. At final follow-up (mean 12, range 9-55 months) all fractures progressed to clinical and radiological union. However, major revision surgery for healing problems was required in 5 cases (6.8%) and minor in 3 cases (4.1%). The average time to healing was 6 (range 3-23) months. Angulation less than 5 degrees in any plane was observed in 66 cases (89.7%), within 5-10 degrees in 5 cases (7.3%) and within 10-15 degrees in 2 cases (2.9%). The mean pre-injury and final follow-up values of Glasgow Outcome Scale were 1.5(1-3) and 1.7(1-3) respectively. Overall 61 patients (83.53%) retained their pre-injury activity status. The Polyax Locked Plating System offers a safe and efficient fixation in distal femoral fractures.

Locking plate fixation versus antegrade nailing of 3- and 4-part proximal humerus fractures in patients without osteoporosis. Comparative retrospective study of 63 cases

INTRODUCTION

There is no consensus on the treatment of proximal humeral fractures. The goal of the present retrospective observational study was to compare functional and radiological results and complications of internal fixation using locking plates versus antegrade nailing in the treatment of non-osteoporotic Neer classification 3- and 4-part fractures after a least 1 year of follow-up.

MATERIAL AND METHODS

Internal fixation was performed in 67 fractures (1 bilateral): 35 by locking plate (1 lost to follow-up, 1 deceased) and 32 by intramedullary nailing (2 lost to follow-up) between January 1st, 2004 and December 31st, 2010. Thus, the study included 33 plates (21 3-part and 12 4-part fractures) and 30 nails (21 3-part and nine 4-part fractures). Final functional assessment was based on the Oxford, Constant, Relative Constant and QuickDASH scores and percentage of handicap. Radiological follow-up included immediate postoperative, 6 weeks, 3 months and 1 year AP and Lamy lateral views. All complications were recorded prospectively.

RESULTS

Mean Oxford, Constant, Relative Constant and QuickDASH scores and percentage of disability for the plate and nail groups respectively were: 23.8 vs. 23.3, 59.7 vs. 60 6, 73.5 vs 79.3, 20.9 vs 21.0, 22.6 vs 22.6. Multivariate analysis did not show any significant difference in functional scores or quality of reduction: final unsatisfactory reduction on AP view, 30.3 vs. 36.7%; lateral view, 3.2 vs. 10.0%; greater tuberosity, 9.1 vs. 16.7%. Four-part fracture (P<0.05), frontal reduction defect at follow-up (P<0.05) or greater tuberosity defect (P>0.05) had negative impacts on functional scores. The complication rates corresponded to those in the literature and did not differ between the techniques (P=0.1901) except for three infections in the plate group.

DISCUSSION-CONCLUSION

Internal fixation is the treatment of choice for 3- and 4-part fractures in non-osteoporotic patients. Although no difference was found in the present study between locking plate and intramedullary nailing, the former seems to be less well adapted and more aggressive.

TYPE OF STUDY

Retrospective observational study.

LEVEL OF EVIDENCE

Level 4.

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.

Mid term results of distal femoral fractures treated with a polyaxial locking plate: a multi-center study

Objective :

Locking plates have become a standard implant in the treatment of distal femoral fractures. Newer designs allow polyaxial screw placement as well as the ability to lock the lag screws.

Methods :

The consecutive multi-centre study cohort consists of all distal femoral fractures treated with the NCB® Distal Femur plate (Zimmer, Warsaw, USA) and a minimum follow-up of twelve months. Fracture classification according the AO/ OTA system and the trauma mechanism radiological evaluation and complications were documented. Clinical evaluation consisted of the Short Form SF12 questionnaire (SF12), the Hospital for Special Surgery Score (HSS) and clinical assessment of range of motion.

Results :

Twenty-five patients with twenty-six fractures were available for follow-up with a minimum required follow-up of twelve months. 81% of the fractures were intra-articular. 48% of the patients were multi-traumatised, 38% having open fractures. All except two went to union (92%) with the primary procedure. The HSS Score was 79 (32-99) and the SF 12 (physical and mental) 40 (19-57) and 54 (21-66) at follow-up. There were five patients requiring surgical revision (19%).

Conclusion :

These fractures are often combined with concomitant injuries. Using modern locked implants high union rates can be achieved with a good function and patient satisfaction when respecting biologic and biomechanical principles.

A comparative biomechanical study for complex tibial plateau fractures: nailing and compression bolts versus modern and traditional plating

AIM

To compare the biomechanical properties of a newly proposed technique, utilizing intramedullary nailing and compression bolts, for the osteosynthesis of intra-articular proximal tibial fractures with meta-diaphyseal comminution, with modern and conventional plating techniques.

METHODS

Fifteen left tibia 4th generation composite Sawbones models (in 3 groups of 5 for each technique) with identically reproduced type VI Schatzker tibial plateau fractures, including meta-diaphyseal dissociation, were used. Three different techniques of osteosynthesis were tested: (a) a new technique that combines intramedullary nailing and compression bolts, (b) internal fixation with a single lateral locking plate and (c) internal fixation with dual buttress plating technique. The model-device constructs were successively subjected to 500N, 1000N and 1500N load levels with five cycles applied at each level on both articular compartments and a final load cycle to failure. Four parameters were recorded for each technique: the average reversible or irreversible displacement in vertical subsidence, the horizontal diastasis of the intra-articular fracture, the average passive construct stiffness and the load to failure.

RESULTS

The new intramedullary nailing technique provided rigid intra-articular osteosynthesis being statistically similar to dual buttress plating for subsidence at medium and higher load levels. At the same time the proposed technique provided statistically equivalent stiffness values to the single lateral locking plate incarnating the rational of biologic fixation. Average load to failure was 1611N for single lateral locking plates, 2197N for intramedullary nailing and 4579N for dual buttress plating. The single lateral locking plate technique had the worse results in interfragmentary displacement while dual buttress plating was superior in stiffness from the other 2 techniques. The mode of failure differed between techniques, with collapse of medial plateau occurring exclusively in the single lateral locking plates group.

CONCLUSION

The proposed new technique of intramedullary nailing and compression bolts demonstrates a flexural behaviour similar to single lateral locking plates, which complies with the terms and benefits of biological fixation, while at the same time maintains a rigid intra-articular stability similar to the stiff dual buttressing plating technique.

The use of locking plates in proximal humeral fractures: Comparison of outcome by patient age and fracture pattern

Purpose:

This study was undertaken to evaluate the efficacy of a proximal humeral locking plate, and to specifically study the effect of patient age and fracture type on the outcome.

Materials and Methods:

Thirty-one cases of proximal humeral fractures fixed by using the proximal humeral interlocking (PHILOS) plate were reviewed.

Results:

Average functional scores (minimum 18 months post operation) per AO / ASIF fracture type were 25.3 for type A, 21.4 for type B, and 22.7 for type C. There was no statistically significant difference between the groups. The functional scores for patients over 65 years of age were significantly inferior (P = 0.03). At a final radiological review (mean 12 months post operation), 30 (96%) of the patients demonstrated fracture union. Seven patients (22.5%) required a second surgical procedure.

Conclusion:

We obtained both good functional results and bone healing with the PHILOS plate, irrespective of fracture type; the older patients had a poorer outcome. We caution the surgeons on the high potential for reoperations with its use.