Soft Tissue Tension Research Articles

Pressing Intervention Promotes the Skeletal Muscle Repair of Traumatic Myofascial Trigger Points in Rats.

ObjectiveTo observe the effect of pressing intervention on the skeletal muscle repair of myofascial trigger points (MTrPs) in rats and explore the mechanism of pressing intervention on the deactivation of trigger points.MethodsThirty SPF rats were randomly divided into blank group, model group and press group, with 10 rats in each group. The MTrPs models were established by blunt striking plus eccentric exercise, and then evaluated. The press group was given a pressing intervention with a self-made device for 14 days, and the rats in the other two groups were fed normally. Soft tissue tension (STT) D0.2 and pressure pain threshold (PPT) were measured before and after intervention. The skeletal muscle tissue at MTrPs was extracted and assessed by hematoxylin–eosin (HE) and Masson staining. The expression of collagen I, collagen III, α- smooth muscle actin (α-SMA), myosin heavy chain (MHC) and fibronectin (FN) were detected by Western Blotting. Enzyme linked immunosorbent assay (ELISA) was used to evaluate the expression of substance P (SP), 5-hydroxytryptamine (5-HT), cyclooxygenase 2 (COX-2) and prostaglandin E2 (PGE2).Results(1) Compared with the blank group, the PPT and D0.2 reduced (P < 0.05) in the model group; while compared with the model group, the PPT and D0.2 increased (P < 0.05) in the press group. (2) Compared with the blank group, the model group showed obvious spontaneous potentials with higher amplitude and frequency, which were also much higher than those of the press group (P < 0.05). (3) The HE and Masson staining results showed evident fibrosis in the muscle tissue of the model group, with a larger area of collagen fibers relative to that of the press group (P < 0.05). (4) The amount of collagen I, collagen III, FN, α- SMA, SP, 5-HT, COX-2 and PGE2 increased and the content of MHC decreased (P < 0.05) in the model group, as compared to the blank group; while all the substances (P < 0.05), instead of MHC which increased (P < 0.05), in the press group were decreased as compared to the model group.ConclusionPressing intervention on the MTrPs in rats can alleviate chronic inflammation, inhibit fibrosis, promote skeletal muscle repair and relieve pain.

Bilobed Flap in Hand Clinodactyly Reconstruction: Technique Description and Result Appraisal.

Objective Clinodactyly is a congenital hand deformity that is characterized by coronal angular deviation and may occur in thumbs or fingers. Surgical treatment is indicated for severe angulations. Among the described techniques, one of the options consists of bone alignment by wedge-shaped addition osteotomy of the anomalous phalanx. Such alignment maneuver creates a problem in skin cover, along with soft-tissue tension at the concave aspect of the deformity. Hence, some sort of skin flap is required for the adequate operative wound closure. We aim to demonstrate the aforementioned technique and to assess the results of bilobed flap in the treatment of hand clinodactyly. Methods Retrospective study conducted between January 2008 and January 2015. Five patients were included in the study, including nine operated digits. Surgical indication consisted of angular deviations ˃ 30 o . Neither patients with thumb deformities nor those with deformities associated to syndromes were excluded from the study. We assessed the functional and cosmetic outcomes of the technique, as well as complications and the satisfaction rates of the family. Results All patients had satisfactory functional and cosmetic results, with a mean skin healing of 18.6 days. Among nine operated digits, only one of the patients presented vascular compromise at the distal portion of the first flap lobe, albeit without necrosis or the need for any additional procedure. Patients were followed up on a minimum of 12-month interval. No deformity recurred during the observation period. Conclusion Bilobed flap for the treatment of hand clinodactyly is a good option for skin cover after the osteotomy.

Using MRI Measurement to Improve Accuracy of Femoral Component Sizing in Oxford Unicompartmental Knee Arthroplasty.

Unicompartmental knee arthroplasty (UKA) can achieve better kinematics and faster recovery than total knee arthroplasty. The Phase III Oxford UKA system has five sizes of femoral components to approximate the normal knee geometry. However, these different sizes may also induce problems, such as the misselection of component size. Different criteria have been proposed to predict the ideal size preoperatively. However, no single method can be applied universally. Therefore, this study aimed to develop a preoperative measurement using knee magnetic resonance imaging (MRI) to predict femoral component size. A total of 68 patients who underwent UKA were investigated from June 2019 to April 2020. 16 knees using a different MRI protocol were excluded. We developed an MRI measurement method to determine femoral size instead of gender- and height-based methods. The accuracy of different methods was compared using postoperative true lateral view radiographs. Three different kinds of gender- and height-based criteria, preoperative templating and intraoperative spoon measurement were compared. The accuracy of MRI measurement was 90.3%. Therefore, a significant difference was found between MRI measurements and all other methods, such as templating or gender- and height-based methods. In conclusion, the MRI measurement method can be concluded to accurately predict femoral component size in UKA. This method could be used regardless of different ethnic groups, individual knee geometry, or soft tissue tension.

English

Treatment of complex malocclusion poses a challenge for the orthodontist because of its multifactorial aetiology. Class II malocclusion is the most frequently encountered and treated malocclusion in orthodontic practice and affects approximately 14.6 % of the North Indian population.1 A common reason for Class II malocclusion is mandibular skeletal retrusion which is the most common characteristic, as reported by McNamara.2 This can be caused by genetic or hereditary factors. When evaluating treatment options for Class II patients, the extent of the skeletal discrepancy and the skeletal maturity of the patient needs to be considered. Treatment may range from dental compensation including camouflage with extractions to surgical procedures targeted at moving the jaw at fault. In growing patients, growth modification with functional appliances offers an intermediate treatment option. Functional appliances are basically of two types; Removable and Fixed. Removable functional appliances such as Activator, Bionator, Frankel Function regulator and Twin Block appliance change Class II relationship by the transmission of soft tissue tension to the dentition. Treatment success with these appliances relies heavily on patient compliance. Therefore, in non-compliant patients, fixed Class II correctors in conjunction with fixed orthodontic appliances are the best choice.3 Fixed functional appliances generate continuous stimuli for mandibular growth without break and permit better adaptation to functions like mastication, swallowing, speech and respiration.1 The Herbst fixed functional appliance has been used routinely for Class II patients and has undergone many design variations over time.4 The AdvanSync2 Class II corrector is a recently introduced fixed functional appliance. It has a much smaller size than the conventional Herbst appliances, is easier to place, activate and remove and most importantly, can be used in conjunction with full-arch fixed appliances throughout.3 Here we describe a case report of a patient treated with the AdvanSync2 Class II corrector and the findings observed in the sagittal and vertical dimensions

Shortening effect influence of Distal Minimally Invasive Metatarsal Osteotomy in primary metatarsalgia

In primary metatarsalgia, Distal Minimally invasive Metatarsal Osteotomy (DMMO) achieves a correct load distribution which is a factor in pain relief, but contrary to the elevation of the metatarsal head, shortening the metatarsal length has no influence on plantar-loading parameters, while the increased metatarsal length is a factor in the development of metatarsalgia. Thus, we hypothesized that metatarsalgia could be partly related to a functional imbalance between bone structure and soft tissues and pain relief after DMMO results from soft tissue relaxation. Many authors have highlighted the correlation between joint pressure and periarticular soft tissue tension. To test our hypothesis, we measured intra-operatively the MTPJ pressure of 19 patients suffering from primary metatarsalgia, before and after DMMO. This pressure is being analyzed as a reflection of joint decompression and forefoot soft tissue release. Many authors have highlighted the correlation between joint pressure and periarticular soft tissue tension. Lower metatarsals presenting metatarsalgia show a significantly lower MTPJ pressure compared to asymptomatic rays, and DMMO induces a significant increase of MTPJ pressure. Those variations reflect the functional imbalance between bone structure and soft tissue in primary metatarsalgia. The biomechanical rationale of the shortening effect of DMMO could therefore be explained by the release of forefoot soft tissue, which could take part in the pain relief by restoring this balance.

Observation on the clinical effect of self-designed modified rhomboid skin flap in facial wound repair

Objective: To investigate the clinical effect of self-designed modified rhomboid flap in repairing rhomboid, round, and teardrop-shaped wounds on the face. Methods: A retrospective observational study was conducted. From August 2018 to April 2020, 30 patients with facial lesions admitted into Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine and the People's Hospital of Jianchuan County in Yunnan province met the inclusion criteria, including 16 males and 14 females, aged 23 to 88 years. The wound area ranged from 1.0 cm×1.0 cm to 7.0 cm×5.0 cm, with 10 cases of rhomboid wounds, 12 cases of round wounds, and 8 cases of teardrop-shaped wounds. The self-designed modified rhomboid flaps were applied to repair the wounds and after that, the patients were followed up for 1 to 18 months to record the survival of flaps, wound tension, scar formation and complications after surgery. Results: No necrosis or blackening was observed at the tip of the flaps after surgery. All the flaps survived and the wounds healed well with little tension, minimal scars, and no complications. Conclusions: The self-designed modified rhomboid flap is especially suitable for facial wounds with multiple important organs, multiple anatomical subunits, and areas with large changes in soft tissue tension, which can reduce not only the rotation of the flap, but also unnecessary excision of normal skin and soft tissue.

A prospective randomised control trial comparing functional with mechanical axis alignment in total knee arthroplasty: study protocol for an investigator initiated trial

BackgroundA drive to improve functional outcomes for patients undergoing total knee arthroplasty (TKA) has led to alternative alignment being used. Functional alignment (FA) uses intraoperative soft tissue tension to determine the optimal position of the prosthesis within the patient’s soft tissue envelope. Angular limits for bone resections are followed to prevent long-term prosthesis failure. This study will use the aid of robotic assistance to plan and implement the final prosthesis position. This method has yet to be compared to the traditional mechanically aligned (MA) knee in a randomised trial.MethodsA blinded randomised control trial with 100 patients will be undertaken via Perth Hip and Knee Clinic. Fifty patients will undergo a MA TKA and fifty will undergo a FA TKA. Both alignment techniques will be balanced via computer-assisted navigation to assess prosthetic gaps, being achieved via the initial bony resection and further soft tissue releases as required to achieve satisfactory balance. The primary outcome will be the Forgotten Joint Score (FJS) 2 years after surgery, with secondary outcomes being other patient-reported outcome measures, clinical functional assessment, radiographic position and complications. Other data that will be collected will be patient demography (sex, age, level of activity) and medical information (grade of knee injury, any other relevant medical information). The linear statistical model will be fitted to the response (FJS), including all the other variables as covariates.DiscussionMany surgeons are utilising alternative alignment techniques with a goal of achieving better functional outcomes for their patients. Currently, MA TKA remains the gold standard with good outcomes and excellent longevity. There is no published RCTs comparing FA to MA yet and only two registered studies are planned or currently in progress. This study utilises a FA technique which differs from the two studies. This study will help determine if FA TKA has superior functional results for patients.Trial registrationThis trial has been registered with the Australian New Zealand Clinical Trials Registry (ANZCTR) http://www.anzctr.org.au: U1111-1257-2291, registered 25th Jan 2021. It is also listed on www.clinicaltrials.gov: NCT04748510.

Cephalomedullary Nail as a Definitive Antibiotic Spacer for Multidrug Resistant Periprosthetic Infection of a Proximal Femoral Endoprosthesis

Introduction: Periprosthetic hip infections in the setting of massive proximal femoral bone loss pose a complex challenge to both patients and arthroplasty surgeons alike. As these patients are often multiply revised and can be infected with multidrug resistant organisms, the likelihood for a successful outcome with the gold-standard 2-stage revision is significantly diminished, and definitive management is often achieved with amputation or an antibiotic eluting cement spacer. With reduced bone stock and poor soft tissue tension, creation of such a spacer to not only provide local drug delivery, but also achieve length, stability, and confer some degree of mobility to these patients is technically demanding, and has been fraught with mechanical complications in recent literature. Materials and Methods: The purpose of this article is to report on a novel technique for definitive management of prosthetic joint infection in the setting of massive proximal femoral bone loss. This is a case of a 61-year-old medically complex patient with an infected proximal femoral endoprosthesis colonized with multidrug resistant bacteria, treated with creation of a novel articulating antibiotic eluting massive proximal femoral cement spacer with a cephalomedullary nail as definitive management. Results: In our patient we have had successful suppression of his life-threatening infection and enabled partial weight bearing on the affected extremity at 1 year postoperatively. Conclusion: Articulating antibiotic eluting cement proximal femoral spacer with a cephalomedullary nail is a viable surgical option for definitive management of prosthetic joint infection in the setting of massive proximal femoral bone loss.

Spontaneous Correction of External Tibiofemoral Rotational Deformity and Tibial Tuberosity-Trochlear Groove Measurements Occurs After Medial Patellofemoral Ligament Reconstruction in Fixed or Obligatory Dislocators

Objectives:Tibial tubercle to trochlear groove distance (TT-TG) and external tibiofemoral rotation (TFR) through the knee joint have been identified as potential contributing factors to patellar instability. In patients with a fixed or obligatory lateral patella dislocation (FOD), the normal force vector of the extensor mechanism is altered, so instead of a direct axial pull to cause extension, it exerts a lateralizing and external rotatory force on the tibia via the tibial tubercle. The purpose of this study is to investigate postoperative changes in TT-TG and TFR after medial patellofemoral ligament reconstruction (MPFLR) in two clinical cohorts: standard traumatic patellar instability (SPI) patients and FOD patients. We hypothesized that by surgically relocating the patella in the trochlea, and re-establishing medial sided soft tissue tension, the increased medializing force vector on the patella may exert enough force to alter resting rotation of the tibia in relation to the femur in the FOD group.Methods:A retrospective study was performed from April 2009 to February 2019. FOD and SPI patients under 18 years with available magnetic resonance imaging (MRI) of the knee before and after MPFLR were eligible. All FOD patients in the time frame were analyzed and SPI patients were randomly selected. Exclusion criteria were outside institution MRI, concomitant alignment procedures done at the time of MPFLR, and prior MPFLR or tibial tubercle osteotomy. TT-TG and TFR (using the posterior femoral and tibial condylar lines) were measured blindly on initial axial MRI. Statistical analysis using a paired sample t-test was performed with significance set at p<0.05.Results:A total of 30 patients were included, 14 in the FOD group and 16 in the SPI group. The mean age at time of surgery was 13.9 years (range 10-17 years), 53% of the cohort was female, and the mean time from surgery to follow-up MRI was 2.0 years. Demographics by group are shown in Table 1. TT-TG and TFR were not significantly different preoperatively versus postoperatively in the SPI group (Table 2). In the FOD group, both TT-TG (17.7 vs 13.7, P=.019) and TFR (8.6 vs 3.1, P=.025) decreased significantly on postoperative MRI.Conclusions:The postoperative decrease in TT-TG and TFR in the FOD group suggests that MPFLR in fixed or obligatory dislocators can improve the external rotation deformity through the level of the joint, and thus may help normalize the forces acting through the extensor mechanism.

SPONTANEOUS CORRECTION OF EXTERNAL TIBIOFEMORAL ROTATION AND TIBIAL TUBEROSITY-TROCHLEAR GROOVE DISTANCE OCCURS AFTER MEDIAL PATELLOFEMORAL LIGAMENT RECONSTRUCTION IN FIXED OR OBLIGATORY DISLOCATORS

Background:Tibial tubercle to trochlear groove distance (TT-TG) and external tibiofemoral rotation (TFR) through the knee joint have been identified potential contributing factors to patellar instability. In patients with a fixed or obligatory lateral patella dislocation (FOD), the normal force vector of the extensor mechanism is altered, so instead of a direct axial pull to cause extension, it exerts a lateralizing and external rotatory force on the tibia via the tibial tubercle.Hypothesis/Purpose:The purpose of this study is to investigate postoperative changes in TT-TG and TFR after medial patellofemoral ligament reconstruction (MPFLR) in two clinical cohorts: standard traumatic patellar instability (SPI) patients and FOD patients. We hypothesized that by surgically relocating the patella in the trochlea, and re-establishing medial sided soft tissue tension, the increased medializing force vector on the patella may exert enough force to alter resting rotation of the tibia in relation to the femur in the FOD group.Methods:A retrospective study was performed from April 2009 to February 2019. FOD and SPI patients under 18 years with available magnetic resonance imaging (MRI) of the knee before and after MPFLR were eligible. All FOD patients in the time frame were analyzed and SPI patients were randomly selected. Exclusion criteria were outside institution MRI, concomitant alignment procedures done at the time of MPFLR, and prior MPFLR or tibial tubercle osteotomy. TT-TG and TFR (using the posterior femoral and tibial condylar lines) were measured blindly on initial axial MRI. Statistical analysis using a paired sample t-test was performed with significance set at p<0.05.Results:A total of 30 patients were included, 14 in the FOD group and 16 in the SPI group. The mean age at time of surgery was 13.9 years (range 10-17 years), 53% of the cohort was female, and the mean time from surgery to follow-up MRI was 2.0 years. Demographics by group are shown in Table 1. TT-TG and TFR were not significantly different preoperatively versus postoperatively in the SPI group (Table 2). In the FOD group, both TT-TG (17.7 vs 13.7, P=.019) and TFR (8.6 vs 3.1, P=.025) decreased significantly on postoperative MRI.Conclusion:The postoperative decrease in TT-TG and TFR in the FOD group suggests that MPFLR in fixed or obligatory dislocators can improve the external rotation deformity through the level of the joint, and thus may help normalize the forces acting through the extensor mechanism.Tables/ Figures

Neglected сlubfoot treated by Ilizarov and Ponseti methods

The Ponseti method has revolutionized clubfoot treatment. Though completely neglected clubfeet are now rare, partially or incompletely and improperly treated feet are not uncommon. Relapses after successful correction may occur due to non-compliance with bracing. In scarred soft tissues due to previous surgery, soft tissue distraction using external fixation helps achieve correction. The Ilizarov fixator permits us to follow the Ponseti protocol, using correction methods that may either be constrained or unconstrained by hinges. Applying force vectors perpendicular to the moment arm allows us to correct the еquinus without damaging the ankle joint. All of the above is possible when the talus is round. Full correction of the deformity is possible. However, longterm follow-up of these patients has revealed stiffness of the ankle setting and frequently with tibio-talar osteophytes anteriorly. They are probably a reaction to excessive pressure developed in the joint due to the tight soft tissues. Hence the author has now added a mild shortening of the tibia and fibula to reduce soft tissue tension, rather than resorting to further soft tissue releases through scarred tissues. This allows faster correction with the Ponseti-Ilizarov protocol and allows good ankle range of motion to persist.

Current concepts in total knee arthroplasty : mechanical, kinematic, anatomical, and functional alignment.

Limb alignment in total knee arthroplasty (TKA) influences periarticular soft-tissue tension, biomechanics through knee flexion, and implant survival. Despite this, there is no uniform consensus on the optimal alignment technique for TKA. Neutral mechanical alignment facilitates knee flexion and symmetrical component wear but forces the limb into an unnatural position that alters native knee kinematics through the arc of knee flexion. Kinematic alignment aims to restore native limb alignment, but the safe ranges with this technique remain uncertain and the effects of this alignment technique on component survivorship remain unknown. Anatomical alignment aims to restore predisease limb alignment and knee geometry, but existing studies using this technique are based on cadaveric specimens or clinical trials with limited follow-up times. Functional alignment aims to restore the native plane and obliquity of the joint by manipulating implant positioning while limiting soft tissue releases, but the results of high-quality studies with long-term outcomes are still awaited. The drawbacks of existing studies on alignment include the use of surgical techniques with limited accuracy and reproducibility of achieving the planned alignment, poor correlation of intraoperative data to long-term functional outcomes and implant survivorship, and a paucity of studies on the safe ranges of limb alignment. Further studies on alignment in TKA should use surgical adjuncts (e.g. robotic technology) to help execute the planned alignment with improved accuracy, include intraoperative assessments of knee biomechanics and periarticular soft-tissue tension, and correlate alignment to long-term functional outcomes and survivorship.

Radiographic outcomes of patients undergoing reverse shoulder arthroplasty using inlay versus onlay components: is there really a difference?

IntroductionAchieving soft tissue tension in RSA occurs by displacement of the humerus from the glenoid. We compared the lateral and inferior humeral displacement of two RSA systems radiographically. Each system utilized a humeral implant with a 135-degree neck-shaft angle and offered lateralized glenospheres. One had an onlay component and the other an inlay. Our primary hypothesis was that an alteration of surgical technique would negate the differences in their geometries radiographically. Secondarily, we sought to determine if a difference in complications or revisions occurred with these different designs. MethodsTwo hundred and eleven patients underwent RSA by a single surgeon with either an inlay or onlay prosthesis over a 2-year period. A true AP Grashey radiograph was utilized to measure: 1) Glenohumeral offset (GHO); 2) Acromiohumeral distance (AHD); 3) Pivot point (PP); 4) Humeral head cut surrogate (HHC) and 5) Humeral Socket Depth (HSD). Complications recorded included postoperative acromial fractures, revision for any reason, instability, and infections. ResultsThere was no significant difference in GHO or AHD between the two groups. There was a difference in PP and HHC between the groups (P < .001). The onlay group had an HHC 1.8 mm larger than inlay. Of the inlay group patients, 66% had their humeral tray placed above the level of the humeral osteotomy. DiscussionA larger HHC in the onlay group and implanting the inlay above the humeral osteotomy negates differences in AHD and GHO. Level of evidenceLevel III; Retrospective Comparative Study

Morphological Changes In Bone Tissue In Chronic Osteomyelitis On The Background Of Application Of Plate Concentrate

The method of laser osteoperforation developed experimentally was approved in 142 patients with chronic osteomyelitis of different forms. A diode laser was used in which wavelength was 970 nm and power – 30 W. Laser osteoperforation was performed transcutaneously in a contact way with a quartz light guide of 0, 4 mm diameter in the projection of bone destruction foci with formation of 2-20 holes. Normalization of temperature and blood indices as well as pain decrease, reduce of soft tissue tension and edema was observed in all the patients in the immediate days after surgery. As a rule, fistulae closed by 4-10 day. In case of chronic osteomyelitis persistent remission is noted during 2-5 years by the objective data (roentgenography, flowmetry, densitometry). Thus, the experience of laser osteoperforation clinical use demonstrates its high effectiveness in treatment of osteomyelitis different forms. The method is of little invasiveness and it allows to reduce the periods of treatment and rehabilitation to a great extent.

Stem retention and survival in revision of anatomical convertible shoulder arthroplasty to reverse arthroplasty: a Dutch registry study

BackgroundConvertible stem designs allow for stem retention during revision from anatomical to reverse shoulder arthroplasty. In some cases conversion is not possible for example due to excessive soft tissue tensioning. In these cases a total revision is necessary. The primary aim of this Dutch registry study was to evaluate the unforeseen stem reversion percentages in revision of convertible anatomical shoulder arthroplasty to reverse shoulder arthroplasty.MethodsShoulder arthroplasties (n = 2834) performed between 2014 and 2016 registered in the Dutch Arthroplasty Registry were selected. In 2016 94% of primary arthroplasties and 92% of revision arthroplasties were registered in the database. Arthroplasties were selected on convertibility. Mean follow-up was 2.4 years. We analysed the number of revisions for convertible and non-convertible designs. Cases with obligatory revisions as periprosthetic joint infections, stem loosening and periprosthetic fractures were excluded. Kaplan-Meier analysis was used to calculate humeral stem survival. Multivariate cox-regression analysis was used to determine risk factors for stem revision.ResultsThe majority of procedures (respectively 90.9 and 72.1% for the convertible and non-convertible group) concerned a conversion to reverse shoulder arthroplasty (p = .02). In the convertible group, the stem was retained in 29 out of 40 patients (72.5%). Overall implant survival was 94.5% after a mean follow-up of 2.4 years. Hemiartroplasty, fracture as primary indication, previous shoulder surgery and lower age were risk factors for revision.ConclusionsAlthough convertible designs are gaining popularity due to their expected advantage in revision arthroplasty, surgeons should be aware that during a revision procedure in 27.5% of the patients an unforeseen stem revision is necessary.

Comparison and appraisal of techniques for the determination of material loss from tapered orthopaedic surfaces

This review examines the challenges associated with quantifying material loss at modular junctions. Determination of material loss from retrieved orthopaedic surfaces is regarded as a prerequisite for the evaluation of long-term implant performance. Methods previously adopted to overcome the challenges associated with determining material loss from non-articular surfaces will be presented and discussed in this paper.Total Hip Replacement (THR) is regarded as one of the most successful and cost-effective surgical interventions for the treatment of advanced osteoarthritis. The use of modular components offers surgeons an array of possible implant combinations to intraoperatively optimise range of motion and soft tissue tension. However, the taper interface used to connect modular components has been suggested to contribute to premature implant failure through the release of metal debris and corrosion products. Geometrical and topographical measurement of explanted modular interfaces has been used to correlate multifarious variables with an absolute volumetric value for material loss. To improve modular implant performance, medical device manufacturers have adopted numerous design philosophies, each presenting a unique set of challenges for the measurement of material loss. This review summarises the approaches used in previous studies to overcome these challenges and identifies future work required in this area. This field of research is currently the subject of discussion within standards bodies to create recommended best practices for centres to follow.

English

BACKGROUND Skeletal class II division 1 malocclusion is an antero posterior discrepancy between maxilla and mandible which is usually treated by functional appliances when the patient is in the growing phase. It has been shown that these functional orthodontic appliances may lead to pressure on the oral mucosa, soft tissue tension, oral constriction, toothache and pain. They may also lead to fatigue or to functional speech and respiratory disorders, and they may affect the appearance of the face. All of these undesired consequences affect the patients’ degree of compliance in a negative manner, and may in turn affect the patients’ perception towards the treatment. This study was conducted to investigate patient perception of treatment need, appliance acceptance, expectations of treatment influence on oral health, value of dental aesthetics and information concerning treatment procedures. METHODS Total 30 samples were selected 15 samples were cases treated with twin block appliance and other 15 samples were treated with clear block appliance. After 8 months of treatment, a questionnaire survey was conducted assessing discomfort, expectations and experiences of all patients being treated with clear block appliance and twin block appliance. RESULTS Clear block seemed to be better with regard to all the parameters used in the study but on statistical analysis the difference between the two groups was insignificant. CONCLUSIONS Clear block appliance was designed to increase the compliance of the patient. However, clear block and twin block appliance have similar effects. KEY WORDS Class II, Clear Block, Twin Block

Effect of Ulnar Head Offset on Distal Radioulnar Joint Stability

A complete ulnar head replacement may be indicated in cases of distal radial ulnar joint (DRUJ) dysfunction to address bony pathology in lieu of using a constrained total DRUJ prosthesis. Complete ulnar head implants are simple, but they may be unstable if soft tissue tension is not adequately restored. We hypothesized that incorporating an increased offset in the complete ulnar head replacement would lead to increased tension on the distal oblique interosseous ligament, increased contact force at the DRUJ, and improved joint stability. Using a specially designed jig, we measured instability by comparing displacement under load (stiffness) of the DRUJ in 10 cadaveric specimens under 4 different conditions: (1) intact, (2) native head after excision of the triangular fibrocartilage complex, (3) replacement of the ulnar head with a standard offset ulnar head, and (4) replacement of the ulnar head with an increased offset ulnar head. No soft tissue repair was done. We measured anteroposterior displacement under load with maximum translation of 10 mm or maximum loads of 50 N. We tested all specimens with the forearm positioned in neutral, supination, and pronation. Excising the triangular fibrocartilage complex decreased the average stiffness of the DRUJ to 46% of the intact state, creating a simulated state of DRUJ instability. Replacing the ulnar head with the standard offset head increased average stiffness to 54% of the intact state. Increasing the ulnar head offset with the simulated total ulnar head replacement increased average stiffness to 77% of the intact state. An increased offset ulnar head replacement improves DRUJ stability compared with a standard anatomic offset ulnar head replacement. Understanding DRUJ morphology and offset is important in the treatment of DRUJ arthritis and instability.

Use of Dual Mobility Acetabular Component and Anterior Approach in Patients With Displaced Femoral Neck Fracture

BackgroundAlthough the antidislocation effect of total hip arthroplasty (THA) via the direct anterior approach (DAA) with dual mobility cup (DMC) for displaced femoral neck fracture (FNF) has already been reported, the clinical result of DMC-DAA-THA for displaced FNF in terms of mortality, complications, and walking ability are still unclear. Methods106 cases with DMC-DAA-THA for displaced FNF were investigated of dislocation; perioperative complications; 3-, 6-, and12-month mortality rate; and pre/early postoperative walking ability. The walking ability was stratified into the following four categories: (1) use of a wheelchair (no walking), (2) walking alongside a support (including walkers designed for the elderly), (3) walking using one stick, and (4) unaided walking. ResultsThere was no dislocation withing one-year postoperative. The 3-, 6-, and 12-month mortality rate was 2.8%, 4.7%, and 5.7%. Total complications occurred in 14 cases (14.7%). Although there was no revision surgery, two cases (1.9%) of intraoperative fracture treated without additional fixation, and one case of postoperative fracture was occurred. Among patients with preinjury walking category 2, 3, and 4 (total 94 cases), the number of patients who recovered same walking category at two-week postoperation was 56 cases (59.6%). ConclusionsOur study demonstrated that DMC-DAA-THA for displaced FNF offered quick recovery of walking ability with no dislocation and low one-year mortality rate. We believe that the combination of early postoperative recovery due to the minimal invasiveness of the DAA and decreased dislocation rate due to increased range of motion by DMC and adequate soft tissue tension by DAA contributed to null dislocation.

Functional alignment achieves soft-tissue balance in total knee arthroplasty as measured with quantitative sensor-guided technology.

Total knee arthroplasty (TKA) using functional alignment aims to implant the components with minimal compromise of the soft-tissue envelope by restoring the plane and obliquity of the non-arthritic joint. The objective of this study was to determine the effect of TKA with functional alignment on mediolateral soft-tissue balance as assessed using intraoperative sensor-guided technology. This prospective study included 30 consecutive patients undergoing robotic-assisted TKA using the Stryker PS Triathlon implant with functional alignment. Intraoperative soft-tissue balance was assessed using sensor-guided technology after definitive component implantation; soft-tissue balance was defined as intercompartmental pressure difference (ICPD) of < 15 psi. Medial and lateral compartment pressures were recorded at 10°, 45°, and 90° of knee flexion. This study included 18 females (60%) and 12 males (40%) with a mean age of 65.2 years (SD 9.3). Mean preoperative hip-knee-ankle deformity was 6.3° varus (SD 2.7°). TKA with functional alignment achieved balanced medial and lateral compartment pressures at 10° (25.0 psi (SD 6.1) vs 23.1 psi (SD 6.7), respectively; p = 0.140), 45° (21.4 psi (SD 5.9) vs 20.6 psi (SD 5.9), respectively; p = 0.510), and 90° (21.2 psi (SD 7.1) vs 21.6 psi (SD 9.0), respectively; p = 0.800) of knee flexion. Mean ICPD was 6.1 psi (SD 4.5; 0 to 14) at 10°, 5.4 psi (SD 3.9; 0 to 12) at 45°, and 4.9 psi (SD 4.45; 0 to 15) at 90° of knee flexion. Mean postoperative limb alignment was 2.2° varus (SD 1.0°). TKA using the functional alignment achieves balanced mediolateral soft-tissue tension through the arc of knee flexion as assessed using intraoperative pressure-sensor technology. Further clinical trials are required to determine if TKA with functional alignment translates to improvements in patient satisfaction and outcomes compared to conventional alignment techniques. Cite this article: Bone Joint J2021;103-B(3):507-514.