Surgical treatment of popliteomeniscal fascicles tears is associated with better patient-reported outcome measures. A systematic review and meta-analysis

PURPOSE

Popliteomeniscal fascicles (PMFs) are a component of the popliteal hiatus complex in the knee, and their injury primarily affects young athletes participating in sports activities involving twisting movements. The identification of PMFs tears presents a challenge, often accompanied by lateral pain and a locking sensation. The objective of this systematic review (SR) and meta-analysis is to enhance the suspicion and recognition of PMFs tears, aiming to facilitate the treatment of this condition, particularly in symptomatic young patients.

METHODS

A comprehensive search, focused on studies examining PMFs injuries and their treatment, was conducted in four databases, PubMed, Scopus, Embase, and Web of Science. The ROBINS-I tool was used to evaluate the risks of bias. The PRISMA flow diagram was used to conduct the research and select the included studies. A meta-analysis was conducted for the Lysholm score, the Tegner Activity Scale, and the subjective IKDC score. The present SR and meta-analysis was registered on PROSPERO.

RESULTS

Five clinical studies were included in the final analysis, comprising 96 patients. All the patients underwent a preoperative MRI assessment and a diagnostic arthroscopy to detect the PMFs tears, with a subsequent surgical procedure either open or arthroscopically performed. Surgery was associated with the resolution of symptoms. A statistically significant improvement in the Lysholm score (p: 0.0005) and the subjective IKDC score (p: 0.003) after the surgical procedure with respect to the preoperative evaluation was found.

CONCLUSION

This SR and meta-analysis showed a significant improvement in the Lysholm score and subjective IKDC score following surgery for PMFs tears. However, controversy persists regarding the optimal surgical approach, with current literature favoring arthroscopic procedures.

LEVEL OF EVIDENCE

IV.

Triggering, clicking, locking and crepitus of the finger: A comprehensive overview

Triggering, locking, clicking, and crepitus of the fingers are common symptoms patients present with. Even though crepitus and triggering can occur as part of the same underlying diagnosis, it is important to differentiate between them, as they usually indicate different possible diagnoses. The differential diagnoses that should be considered include trigger finger, metacarpophalangeal joint (MCPJ) arthritis, fractures or dislocations, extensor digitorum communis subluxation or dislocation, locked MCPJ, avascular necrosis of the metacarpal head, and Dupuytren's disease. A thorough clinical examination with appropriate special investigations can permit the clinician to make the correct diagnosis. Appropriate management of a confirmed diagnosis is successful in providing symptomatic improvement.

Metacarpal Neck Osteochondroma: An Atypical Cause of "Trigger Finger"

"Locking" of the digits is a relatively common patient complaint in hand surgery. Typically, this phenomenon arises from either triggering of tendons at the A1 pulley or subluxation of tendons around the metacarpal head. Although trigger digit and sagittal band injury comprise most diagnoses, clinicians must be aware of rarer entities that alter the underlying osseous anatomy and predispose the digits to "locking." Here, we present a case of metacarpal neck osteochondroma causing subluxation of the index metacarpophalangeal joint radial collateral ligament.

Biomechanical Evaluation of an Oblique Lateral Locking Plate System for Oblique Lumbar Interbody Fusion: A Finite Element Analysis

OBJECTIVE

The oblique lateral locking plate system (OLLPS) is a novel internal fixation with a locking and reverse pedicle track screw configuration designed for oblique lumbar interbody fusion (OLIF). The OLLPS is placed in a single position through the oblique lateral surgical corridor to reduce operative time and complications associated with prolonged anesthesia and prone positioning. The purpose of this study was to verify the biomechanical effect of the OLLPS.

METHODS

An intact finite element model of L1-S1 (intact) was established based on computed tomography images of a healthy male volunteer. The L4-L5 intervertebral space was selected as the surgical segment. The surgical models were established separately based on OLIF surgical procedures and different internal fixations: 1) stand-alone OLIF (SA); 2) OLIF with a 2-screw lateral plate; 3) OLIF with a 4-screw lateral plate; 4) OLIF with OLLPS; and 5) OLIF with bilateral pedicle screw fixation (BPS). After validation of the intact model, physiologic loads were applied to the superior surface of L1 to simulate motions such as flexion, extension, left bending, right bending, left rotation, and right rotation. The evaluation indices included the L4/5 range of motion, the L4 maximum displacement, and the maximum stresses of the superior and inferior end plates, the cage, and the supplemental fixation.

RESULTS

During OLIF surgery, the OLLPS provided multiplanar stability similar to that provided by BPS. Compared with 2-screw lateral plate and 4-screw lateral plate, OLLPS had better biomechanical properties in terms of enhancing the instant stability of the surgical segment, reducing the stress on the superior and inferior end plates of the surgical segment, and decreasing the risk of cage subsidence.

CONCLUSIONS

With a minimally invasive background, the OLLPS can be used as an alternative to BPS in OLIF and it has better prospects for clinical promotions and applications.

Three concomitant locked finger metacarpophalangeal joints caused by degenerative metacarpal heads: Case report

A locked metacarpophalangeal joint (LMCP) is a rare condition often confused with trigger finger. Its causes are numerous and typically divided into two broad categories: acquired LMCP in younger patients, and degenerative LMCP in older patients. This pathology usually affects only one MCP. Even though several external reduction techniques have been described, the main risk of non-surgical reduction treatment is recurrence. Thus, its management is most often surgical. We report the case of a 60-year-old woman with 3 simultaneous LMCP (3rd, 4th, and 5th rays of the left hand) due to degenerative metacarpal heads. Surgical treatment was performed and found that locking was due to entrapment of the radial collateral ligament on metacarpal head osteophytes. Full extension was regained at the end of the surgery. The follow-up was uneventful, no recurrence occurred. This case highlights the need for careful examination to prevent medical and surgical wandering for a rare but well-described and easy to treat condition.

A Biomechanical Comparison of Locked Unicortical with Non-Locking Bicortical Screws for Metacarpal Shaft Fractures in a Randomized Human Cadaveric Model

Background: Locking plate fixation is widely used in large long bone fixation and is now available for small "long" bones in the hand. Potential advantages of unicortical locked fixation are reduced risk of over-drilling and therefore reduced risk of damage to surrounding structures and reduced risk of irritation from proud screws. Furthermore, unicortical fixation may be used where bicortical fixation is technically impossible. Our aim was to compare fixation strength of unicortical locked plate fixation with bicortical non-locked fixation in a human cadaveric model, by assessing strength under cyclical loading conditions and load to failure (LTF). Methods: 16 matched pairs of embalmed and refrigerated human cadaveric metacarpals were randomly allocated to either unicortical locked or bicortical non-locked plate and screw fixation. A transverse osteotomy was made. Fractures were stabilized with 2.0 mm self-tapping locking or cortical screws. Each metacarpal was then loaded with a 3-point cantilever testing using a 100 N cell on an Instron materials testing device, cyclically loading them at 1,000 repetitions of 30 N and 50 N. If there was no visible failure of the fixation from cyclical loading they were then loaded to failure with a 1 kN cell. Results: There was a significant difference of average LTF between the bicortical non-locking and unicortical locking of 38.07-59.95 N (p < 0.01). However, both groups showed no statistically significant difference when comparing their performance under cyclical loading. Conclusions: The authors regard unicortical locked fixation as a useful adjunct to standard plating technique.

MR Imaging of the Hypermobile Lateral Meniscus of the Knee: A Case Report

OBJECTIVE

The hypermobile lateral meniscus of the knee is a rarely described entity. In this case report we aim to draw attention to the clinical presentation and MR imaging findings of this pathology.

CASE REPORT

We review the clinical and imaging findings that led to the diagnosis of hypermobile lateral meniscus with transient subluxation causing intermittent locking, and which subsequently led to successful surgical treatment.

CONCLUSION

Hypermobile lateral meniscus is rarely diagnosed prospectively on MR imaging. A better understanding of this uncommon condition will lead to prompt diagnosis and effective treatment, with a better outcome for the patient.

Bilaterally Threaded, Minimal Invasive, Elastic Locking Intramedullary Nailing (ELIN) for the Treatment of Clavicle Fractures

Objective

To evaluate and present the effectiveness of this innovatively designed, elastic locking intramedullary nail (ELIN) in fixation of clavicle fractures.

Methods

The study included 38 patients from July 2014 to July 2017. All of them received intramedullary fixation treated with ELIN, 22 were males and 16 females. The mean age of the patients was 54 years. There were twenty right‐side and 18 left‐side clavicular fractures. Radiographs were taken to assess the fracture type: 21 were type A, 16 type B, and one type C. General anesthesia or cervical block was given to all patients. A small incision of 3–5 cm was given only to those who needed mini‐open reduction. The administration of ELIN and reduction of the fracture was made sure with a C arm machine. After a follow‐up of 8 to 33 months, the clinical outcomes were assessed and evaluated. The constant scores and disabilities of the arm, shoulder and hand questionnaire (DASH) were used to determine the outcomes and functional status of the patients. The study was done accordingly to the guidelines provided by the ethics committee.

Results

Mean operation time was 25.63 min. Mean follow‐up time was 16.5 months. The rate of closed reduction and open reduction was 84% and 16% respectively. There was no shortening of the clavicle. There was no breakage of the nail, though bending of the nail occurred in one patient. Superficial skin infection occurred in three patients at insertion points or the nail tip which was embedded subcutaneously. Skin erosion with nail exposure occurred in a patient with no significant infection. All the other patients had excellent shoulder function. A mini scar was observed in seven patients all the other patients had no scar. Asymmetry was observed in three patients. The mean Constant score was 98.47 and the mean DASH score was 1.55 at the last follow‐up. The implant was removed in all the patients.

Conclusion

Clavicular fractures treated with ELIN is minimally invasive, which presents a safe and novel surgical technique with less complications and a high success rate, excellent aesthetic and quick recovery after surgery. ELIN restores the micro‐dynamic stress at the fracture ends and promotes fracture healing, keeps intact the fracture hematoma and maintains the blood supply, accelerates healing and thus leads to faster osseous healing and better restoration of clavicle length.

A locking compression plate versus the gold-standard non-locking plate with lag screw for first metatarsophalangeal fusion: A biomechanical comparison

INTRODUCTION

The treatment of end-stage first metatarso-phalangeal joint (MTP) arthritis has been arthrodesis. A dorsal non-locking plate with a lag screw has been the standard traditional fixation method. This study compares the biomechanical strength of a locking compression plate (LCP) with and without internal compression versus this known gold standard.

METHODS

In group 1, six matched pairs of cadaver great toes were used to compare the standard non-locking dorsal plate and 3.5mm lag screw to an anatomic locking compression plate in which a lag screw was utilized rather than the internal compression features of the plate. In group 2, another six matched pairs of cadaver great toes were used to compare the gold standard to the locking compression plate, utilizing the plate's internal compression feature instead of a lag screw. A material testing system (MTS) machine applied loads to the MTP joints and measured displacement and stiffness of the constructs. The stiffness of the constructs (Young's modulus) was calculated from the force-displacement curves, and the displacement was measured.

RESULTS

The locking compression plate group that used the compression features of the plate, without the lag screw, had less joint displacement and higher stiffness than control (p<0.05). The same plating construct in which a lag screw was used rather than internal compression of the plate was found to be stiffer than the control (p<0.05), but displacement was not statistically significant.

DISCUSSION

The results suggest that a locking compression plate alone provides the stiffest construct for a first MTP joint fusion.

Atraumatic sequential bilateral locking of the knee joints secondary to dislocation of non-discoid lateral menisci without radiological abnormality

Lateral meniscus dislocation, as a cause of atraumatic knee locking, is often attributed to a discoid meniscus which can be readily diagnosed on MRI. In the absence of radiological abnormality, a dislocated lateral meniscus is a rare occurrence. We present a case of a 14 year old male who presented with atraumatic sequential locking of bilateral knees 6 months apart. Although on both occasions, MRI was normal, arthroscopy demonstrated dislocating lateral menisci that were subsequently surgically stabilised. To date, there have been no reports describing this phenomenon bilaterally in the same patient. A high index of suspicion is needed to evaluate a locked knee in an adolescent in the absence of trauma or a radiological abnormality. Furthermore there is a probability of a similar occurrence in the opposite knee.

Elbow locking in a patient with a congenital radial head dislocation: Case report

Snapping elbow is a rare condition, which has various possible causes such as impinged plica, annular ligament, or other extra-articular causes. We report a case of 15-year-old boy who had snapping elbow and sudden-onset flexion contracture of the elbow. Simple radiographs showed bilateral anterior dislocation of hypoplastic radial heads. Magnetic resonance images with the elbow extended as much as possible showed that the annular ligament hemmed the dislocated radial neck. By surgical incision of the annular ligament which checkreined the radial neck, the patients could regain full extension of the elbow. We recommend careful consideration of surgical excision of ligamentous structure which blocks extension in the patients who have history of snapping elbow with congenital radial head dislocation.

Effectiveness of the surgical torque limiter: a model comparing drill- and hand-based screw insertion into locking plates

Background

The objective of this study is to analyse the effectiveness of the surgical torque limiter during operative use. The study also investigates the potential differences in torque between hand and drill-based screw insertion into locking plates using a standardised torque limiter.

Methods

Torque for both hand and power screw insertion was measured through a load cell, registering 6.66 points per second. This was performed in a controlled environment using synthetic bone, a locking plate and locking screws to simulate plate fixation. Screws were inserted by hand and by drill with torque values measured.

Results

The surgical torque limiter (1.5 Nm) was effective as the highest recorded reading in the study was 1.409 Nm. Comparatively, there is a statistically significant difference between screw insertion methods. Torque produced for manually driven screw insertion into locking plates was 1.289 Nm (95 % CI 1.269–1.308) with drill-powered screw insertion at 0.740 Nm (95 % CI 0.723–0.757).

Conclusions

The surgical torque limiter proved to be effective as per product specifications. Screws inserted under power produce significantly less torque when compared to manual insertion by hand. This is likely related to the mechanism of the torque limiter when being used at higher speeds for which it was designed. We conclude that screws may be inserted using power to the plate with the addition of a torque limiter. It is recommended that all screws inserted by drill be hand tightened to achieve adequate torque values.

Irreducible plantar dislocation of the interphalangeal joint of the great toe due to an accessory sesamoid bone: a case report

INTRODUCTION

Great toe dislocation frequently occurs at the metatarsophalangeal joint. However, an irreducible dislocation of the great toe interphalangeal (IP) joint due to an accessory sesamoid bone is relatively unusual.

CASE REPORT

A 23-year-old woman suffered a dislocated IP joint of the left great toe. The distal phalanx was plantar subluxated, and the articular surface was misaligned. Ultrasound, magnetic resonance imaging, and computed tomography images did not indicate any factors inhibiting reduction. In addition, the sesamoid bone at the IP joint was found to be rotated in the long-axis direction. The sesamoid bone of the IP joint was hooked from the distal direction and occupied the intercondylar area. IP joint of the left great toe was flexed and the distal phalanx was pushed toward the proximal phalanx during reduction locking with fluoroscopic guidance under local anesthesia, and the dislocation was successfully reduced.

DISCUSSION

The sesamoid bone at the IP joint is anatomically located dorsal to the flexor hallucis longus tendon and volar plate. The sesamoid bone fitted exactly in the distal intercondylar area. The sesamoid bone in our patient could be rotated by forcible plantar flexion of the IP joint displaced proximally and hooked into the intercondylar area from the proximal aspect. Then, the distal phalanx was pulled proximally through the volar plate. This is the first report on a plantar dislocation of the IP joint.

1st metatarsophalangeal joint fusion: A comparison of non-union and gender differences between locking and non-locking plating systems

BACKGROUND

Fusion of the first metatarsophalangeal joint (1st MTPJ) is a common surgical procedure used to treat a variety of diseases and deformities of the forefoot. Fixation methods vary and typically fusion rates are good.

OBJECTIVES

The objectives of the study are to demonstrate whether there is any advantage to using locking as opposed to non-locking plates for 1st MTPJ fusion. Additionally the study aims to determine whether there is any difference in non-union rates according to gender.

METHODS

One hundred and seventy two consecutive 1st MTPJ fusions were performed for 153 patients. 40 patients (23%) were male and 132 (77%) female. Twenty patients received Hallu-fix™ plates, 76 Charlotte™ plates and 76 Anchorage™ plates. Postoperative radiographs were reviewed for non-union. Failure rates were compared using Fisher's exact tests (p=0.05).

RESULTS

Twelve (6.9%) non-unions were identified. The difference in failure rates between all systems was not statistically significant. However, the difference in fusion rates between males (17.5%) and females (3.8%) was significant.

CONCLUSION

This study finds that 1st MTPJ fusion is an effective method to treat diseases of the 1st MTPJ. Locking plates may offer better fusion rates than their non-locking counterparts. This is especially evident in male patients.

A Pitfall in Fixation of Distal Humeral Fractures with Pre-Contoured Locking Compression Plate

Anatomically precontoured locking plates are intended to facilitate the fixation of articular fractures and particularly those associated with osteoporosis. Fractures of the distal humerus are relatively uncommon injuries where operative intervention can be exceptionally challenging. The distal humeral trochlea provides a very narrow anatomical window through which to pass a fixed-angle locking screw, which must also avoid the olecranon, coronoid, and radial fossae. We describe 3 patients (ages 27, 49, and 73 years) with a bicolumnar fracture of the distal humerus where very short distal locking screws were used. Intra-articular screw placement was avoided but loss of fixation occurred in two patients and a third was treated with a prolonged period of immobilization. We postulate that fixed-angle screw trajectories may make it difficult for the surgeon to place screws of adequate length in this anatomically confined region, and may lead to insufficient distal fixation. Surgical tactics should include placement of as many screws as possible into the distal fragment, as long as possible and that each screw passes through a plate without necessarily locking in.

Ligament preserving technique for a locked metacarpophalangeal joint of the index finger

BACKGROUND

Locking of metacarpophalangeal joint (MPJ) of the index finger occurs when volar radial osteophytes of the metacarpal head catch the accessory collateral ligament. We devised a ligament-preserving approach to quickly restore the MPJ motion while protecting the radial collateral ligament.

METHODS

We retrospectively reviewed the results of nine patients treated for a locked MPJ of the index finger. In three patients, closed reduction was successful. In six cases, volar radial osteophytes were excised from the metacarpal head using a ligament-preserving technique through a longitudinal incision on the radial side. We analyzed osteophyte shape and height as demonstrated by X-ray and computed tomography (CT). Function was evaluated by examining the range of motion, recurrence, Disabilities of the Arm, Shoulder and Hand (DASH) score, and MPJ stability based on the key pinch strength. One male and eight female patients were followed for an average of 33 months (range, 12 to 65 months); the average age of patients was 41 years (range, 34 to 47 years). The average duration of locking of the MPJ was 23 days (range, 1 to 53 days).

RESULTS

The sharp type of osteophytes was identified in six patients and the blunt type of osteophytes was indentified in three patients. The average height of radial osteophytes on the index finger metacarpal was 4.6 ± 0.4 mm in the axial CT image. At the final follow-up, the average extension limitation decreased from 26° (range, 10° to 45°) to 0°, and further flexion increased from 83° (range, 80° to 90°) to 86°. There was no recurrent locking after surgery. The DASH score improved from 24.3 to 7.2. Key pinch strength improved from 67.3% to 90.4%.

CONCLUSIONS

We obtained satisfactory outcomes in irreducible locking of the MPJ of the index finger by excising volar radial osteophytes of the metacarpal head using a ligament-preserving approach.

Pathoanatomy and treatment modifications of metacarpophalangeal joint locking of the thumb

Ten patients with metacarpophalangeal joint locking of the thumb were studied. Three of them underwent surgical release. During surgery, it was found that the radial sesamoid was seated in a cartilage defect on the volar aspect of the metacarpal head. It appeared that the defect was created by the proximal edge of sesamoid. When the abductor pollicis brevis and flexor pollicis brevis muscles were partially detached from their insertion at the base of the proximal phalanx, the locking could be successfully released. We hypothesize the mechanism of the metacarpophalangeal joint locking of the thumb in our cases was a hyperextension injury that displaced the radial sesamoid distally and radially. In turn, the sesamoid's pointed proximal edge wore a groove in the cartilage on the metacarpal head, and under abductor pollicis brevis and flexor pollicis brevis tension, the radial sesamoid was locked into the cartilage defect; thereby causing locking of the joint.

Results of angular-stable locked intramedullary nails in the treatment of distal tibia fractures

INTRODUCTION

Intramedullary nailing in distal tibial fracture is controversial because of a lack of stability. The present study sought to assess radiological and clinical results for a new "angular-stable" locking system in difficult indications for intramedullary nailing.

MATERIAL AND METHOD

A prospective study recruited 41 patients (41 tibias) with distal tibial fracture consecutively managed using angular-stable locked intramedullary nails. Radiologic assessment comprised AP and lateral lower-limb views, taken postoperatively and through to last follow-up. The mean distance was measured between fracture and joint line. Fusion, with or without malunion, primary reduction defect, non-union and secondary displacement were recorded, as were all complications.

RESULTS

Mean follow-up was 18 ± 5 months; 3 patients were lost to follow-up. Mean fracture distance from the joint line was 63 ± 25 mm. Fusion was achieved within 3 months in 29 cases (76%); delayed fusion in 7 patients (18%) required secondary dynamization at a mean 3 months, with favorable evolution. Revision surgery was required in 2 cases: 1 for secondary displacement exceeding 10°, and 1 for non-union at 7 months. Other complications mainly comprised 4 malunions of less than 10° due to primary reduction defect.

CONCLUSION

Angular-stable locked lower-limb intramedullary nailing provided a very satisfactory fusion rate, with few complications. It is, however, a demanding procedure, especially as regards fracture reduction and nail positioning in the distal fragment.

PROSPECTIVE COHORT STUDY

level IV.

[Randomized prospective study on the influence distal block and Gamma 3 nail on the treatment of intertrochanteric fractures of femur]

OBJECTIVE

The purpose of this study is to assess the need to lock the Gamma 3 nail (Stryker, Mahwah New Jersey USA) distally for intertrochanteric fractures of femur 31-A1 and 31-A2 of the AO.

MATERIAL AND METHODS

Details were recorded on a sample of 177 patients with intertrochanteric femoral fractures treated in our hospital by a standard Gamma nail between June 2011 and January 2013. A prospective study was conducted by randomizing patients by year of birth, even numbers with, or odd number without, distal locking, forming two groups of 90 and 87 fractures, respectively.

RESULTS

The patients treated with a distal locking nail had an increased incidence of medical complications, a lower incidence of biomechanical complications, and an increase in the fracture collapse compared with the control group, with statistical significance (p < 0.05). It is also observed in the group with distal locking increased transfusion requirement and a higher death rate, with statistically significant differences (p < 0.05), but this significance disappears when adjusting for other patient-related characteristics.

CONCLUSIONS

Based on the results found in this work, the use of distal locking screw in the Gamma 3 nails should be restricted to unstable trochanteric fractures after reduction where additional stability to the intramedullary nail is required, and may decrease the risk of complications from use.

Comparison of treatment of unstable intra articular fractures of distal radius with locking plate versus non-locking plate fixation

INTRODUCTION

Unstable intra articular fractures of distal radius are frequently being managed with open reduction and internal fixation. Of late in some biomechanical studies locking plates have been shown to be better in terms of maintenance of radiological parameters in comparison to non-locking plates. We conducted this study to know whether this biomechanical superiority of locking plates is converted in to better clinical outcomes.

MATERIALS AND METHODS

A study was conducted in 60 patients (30 in each group) with unstable intra articular fractures of distal radius who were treated by open reduction and internal fixation with locking plates and non-locking plates. Patients were evaluated for radiological parameters (intra articular step off, radial height, radial tilt, volar tilt) and functional parameters (flexion, extension, radial deviation, ulnar deviation, pronation, supination grip strength) at two year follow up. Overall outcome was evaluated by scoring systems of Gartland and Werley and modified Green O' Brien.

RESULTS

The change in radiological parameters from immediate post op to latest at two year in locking plate group was not significant for radial height, radial tilt, volar tilt, but ulnar variance whereas in non-locking plate there was significant change in radial height, volar tilt, ulnar variance but no significant change in radial inclination. In clinical and functional outcome no significant difference was found at two year follow up.

CONCLUSIONS

Locking plates maintain the radiological parameters better than non-locking plates but functional outcome are same for both plates at two year after surgery.

Locking v/s non-locking reconstruction plates in mandibular reconstruction

Purpose:

To compare the efficacy of locking plates to non-locking plates in the osteosynthesis of mandibular fractures on the basis of clinical parameters.

Materials and Methods:

A prospective randomized clinical trial was conducted at the Faculty of Dental Science, CSMMU (formerly King Georges Medical College), Lucknow, to treat consecutive mandible fractures. The patients were randomly divided into two groups. The patients underwent osteosynthesis—group 1 with 2.4-mm locking titanium plates and group 2 with 2.7 mm non-locking titanium plates. The cause of trauma, the number of days from injury to surgery, average age, gender, and site distribution were all reviewed. The assessment of the patients was done at 1, 3, and 6 weeks and 3 months using the clinical parameters.

Results:

A total of 12 patients with mandibular fractures met the inclusion criteria. In our study, a statistically significant difference was not found in the clinical parameters such as infection, paraesthesia, hardware failure, and mobility between the fracture segments. A statistically significant difference was found between pain and swelling from the previous follow-up visit in groups 1 and 2. In locking group, pain decreases significantly at 3^rd week, 6^th week, 12^th week from 1^st week and pain was absent after 3 week. In non-locking group, pain decreases significantly at 3^rd week, 6^th week and 12^th week from 1^st week but pain was present till 12^th week. Pre-operative swelling was present only in case of non-locking group. Swelling was present in 66.7% of non-locking group and 0% in locking group. After one week swelling was absent in 100% patients at 3^rd, 6^th and 12^th week. Swelling was considerably decreased in locking group as compared to the non-locking group.

Conclusion:

These findings show that the use of locking plates in mandibular fracture was efficacious enough to bear the masticatory loads during osteosynthesis of the fracture. The locking plates provide the advantage of a greater stability, with clinical results almost similar to those seen with non-locking plate osteosynthesis.

Computational modelling of long bone fractures fixed with locking plates - How can the risk of implant failure be reduced?

BACKGROUND AND PURPOSE

The Locking Compression Plate (LCP) is part of a new plate generation requiring an adapted surgical technique and new thinking about commonly used concepts of internal fixation using plates. Knowledge of the fixation stability provided by these new plates is very limited and clarification is still necessary to determine how the mechanical stability and the risk of implant failure can best be controlled.

METHODS

Upon validation, a finite element model of an LCP attached to a cylinder was developed to simulate and analyse the biomechanics of a transverse long bone fracture fixed with a locking plate. Of special interest were the factors influencing the mechanical conditions at the fracture site, the control of interfragmentary movement and implant failure.

RESULTS

Several factors were shown to influence stability in compression. Increasing translation and/or fracture angle post fixation reduced construct stability. Axial stiffness was also influenced by the working length and plate-bone distance. The fracture gap had no effect on the construct stability when no bone contact occurred during loading. Stress analysis of the LCP demonstrated that the maximum Von Mises stresses were found in the innermost screws at the screw-head junction.

INTERPRETATION

For the clinical use of the LCP as a locked internal fixator in fractures with an interfragmentary gap of 1 mm, at least two to four plate holes near the fracture gap should be omitted to allow fracture motion and bone contact to occur. This will also achieve a larger area of stress distribution on the plate and reduce the likelihood of fatigue failure due to cyclic loading.