Comminuted patella fracture in elderly patients: a systematic review and case report

Objectives: To review comminuted patella fracture in the elderly patients and examine the surgical options to avoid compli-cations such as fixation failure and poor functional outcome. To provide an example of mesh augmentation in comminuted patellafracture in the elderly patients. Data Sources: A literature review was conducted by the authors independently using Ovid,Medline, Cochrane, PubMed, and Clinical Key in English. We aimed to review data on patients older than 65 with comminutedpatella fracture. Search conducted between July and December 2015. Study Selection: Search terms included patella fracture,elderly, and fixation failure. Abstracts were included if they were a case report, cohort series, or randomized control trial. Furtherinclusion criteria were that they were available in full text and included patient age(s), operative details, follow-up, and outcomediscussion. Data Extraction: Each study was assessed according to its level of evidence, number of patients, age of patients,fracture patterns described, complications of treatment, and results summarized. Data Synthesis: Paucity of data and het-erogeneity of studies limited statistical analysis. Data are presented as a review table with the key points summarized. Conclusion:In patella fracture, age >65 years and comminuted fracture pattern are predictors of increased fixation failure andpostoperative stiffness, warranting special consideration. There is a trend toward improved functional outcomes when aug-mented fixation using mesh or plates is used in this group. Further level 1 studies are required to compare and validate newtreatment options and compared them to standard surgical technique of tension band wire construc

Total knee arthroplasty in patients with extra-articular deformity

AbstractMultiple acceptable options are available for the correction of distal femoral deformity associated with knee arthritis. The treatment modality should be chosen based on the extent of deformity and attention to preservation of the collateral ligaments. Surgical options range from osteotomy alone, arthroplasty with intra-articular correction, or arthroplasty with extra-articular correction. Different implant choices and fixation methods for the osteotomy possess advantages and disadvantages which need to be considered carefully. In addition to discussing principles of management based on current literature, this article includes a case report using a previously undescribed technique using corrective osteotomy, intramedullary nail fixation, and total knee arthroplasty with computer navigation

Mismatch between trochlear coronal alignment of arthritic knees and currently available prosthesis: a morphological analysis of 4116 knees and 45 implant designs

Purpose: In up to a fifth of total knee replacements (TKR), surgeons are not capable of achieving good clinical and functional results. Despite comprehensive diagnostic workup, an underlying cause is not always identified in these patients. The purpose of this study is to compare native and prosthetic trochlear anatomies, to evaluate a potential source of morphologic mismatch and theoretically, of poor clinical outcomes. Methods: Native trochlear angles of 4116 knee CTs from 360 Knee Systems database of arthritic pre-operative TKR patients were evaluated. A semi-automated tridimensional analysis was performed to define the native trochlear angle in the coronal plane (NTA) among other 142 parameters. An active search was conducted to identify currently available TKR models; prosthetic trochlear orientation in the coronal plane (PTA) was extracted from the technical data provided by manufacturers. Results: The mean native trochlear angle (NTA) was 1.6° ± 6.6° (valgus) with a range from − 23.8° (varus) to 30.3°(valgus). A valgus NTA was present in 60.6% of the knees and 39.4% of them had a varus NTA. 89 TKR models were identified; trochlear details were available for 45 of them, of which 93% were designed with a valgus orientation of the prosthetic trochlear angle (PTA) and 6.9% showed a neutral (0°) PTA. Varus alignment of PTA was not present in any system. Angular numeric values for PTA were available for 34 models; these ranged from 0° to 15° of valgus, with a median value of 6.18° (SD ± 2.88°). Conclusion: This study shows a significant mismatch between native and prosthetic trochlear angles. A relevant proportion of the studied knees (41.45%) fall out of the trochlear angle range of currently available implants; representing a potential source for biomechanical imbalance. While further research is warranted to fully understand the clinical implications of the present study, manufacturers may need to take these findings into account for future implant designs. Level of evidence: Level III, retrospective cohort study

Navigated functional alignment total knee arthroplasty achieves reliable, reproducible and accurate results with high patient satisfaction

Purpose: The decision on which technique to perform a total knee arthroplasty (TKA) has become more complicated over the last decade. Perceived limitations of mechanical alignment (MA) and kinematic alignment (KA) have led to the development of the functional alignment (FA) philosophy. This study aims to report the 2-year results of an initial patient cohort in terms of revision rate, PROMs and complications for Computer Aided Surgery (CAS) Navigated FA TKA. Methods: This paper reports a single surgeon’s outcomes of 165 consecutive CAS FA TKAs. The final follow-up was 24 months. Pre-operative and post-operative patient-reported outcome measures, WOMAC and KSS, and intra-operative CAS data, including alignment, kinematic curves, and gaps, are reported. Stress kinematic curves were analysed for correlation with CAS final alignment and CAS final alignment with radiographic long-leg alignment. Pre- and post-operative CPAK and knee phenotypes were recorded. Three different types of prostheses from two manufacturers were used, and outcomes were compared. Soft tissue releases, revision and complication data are also reported. Results: Mean pre-operative WOMAC was 48.8 and 1.2 at the time of the final follow-up. KSS was 48.8 and 93.7, respectively. Pre- and post-operative range of motion was 118.6° and 120.1°, respectively. Pre-operative and final kinematic curve prediction had an accuracy of 91.8%. CAS data pre-operative stress alignment and final alignment strongly correlate in extension and flexion, r = 0.926 and 0.856, p < 0.001. No statistical outcome difference was detected between the types of prostheses. 14.5% of patients required soft tissue release, with the lateral release (50%) and posterior capsule (29%) being the most common. Conclusion: CAS FA TKA in this cohort proved to be a predictable, reliable, and reproducible technique with acceptable short-term revision rates and high PROMs. FA can account for extremes in individual patient bony morphology and achieve desired gap and kinematic targets with soft tissue releases required in only 14.5% of patients. Level of evidence: IV (retrospective case series review)

Risk factors associated with cardiac complication after total joint arthroplasty of the hip and knee: a systematic review

Background: Cardiac complication represents a major cause of morbidity and mortality after total joint arthroplasty, thus necessitating investigation into the associated risks in total hip arthroplasty and total knee arthroplasty. There remains a lack of clarity for many risk factors in the current literature. The aim of this systematic review is to assess the most recent published literature and identify the risk factors associated with cardiac complication in total hip arthroplasty and total knee arthroplasty. Methods: Scopus, PubMed, CINHAL, and Cochrane were searched to identify studies published since 2008 reporting on risk factors associated with cardiac complication in elective primary in total hip arthroplasty and total knee arthroplasty in patients 18years old with osteoarthritis. Reported odds ratios, hazard ratios, and relative risk were the principal summary measures collected. The included studies were too heterogeneous to enable meta-analysis. Results: Fifteen studies were included in this systematic review. Increasing age and history of cardiac disease were found by most studies to be positively associated with risk of cardiac complication. There was no strong association found between obesity and cardiac complication. The evidence for other risk factors was less clear in the examined literature, although there is suggestive evidence for male gender and cerebrovascular disease increasing risk. Conclusions: Increasing age and history of cardiac disease increases the risk of cardiac complication after total hip arthroplasty and total knee arthroplasty. Other risk factors commonly attributed to increased risk in non-cardiac surgery including hypertension and obesity require further evaluation in arthroplasty. Systematic review registration: A detailed protocol was published in the PROSPERO database (registration number CRD42018095887) for this systematic review

Femoral Component Rotation in Total Knee Arthroplasty Using a Tibia-First, Gap-Balancing, “Functional Alignment” Technique

Background: The purpose of this study was to describe the femoral component rotation in total knee arthroplasty (TKA) using a tibia-first, gap-balancing, “functional alignment” technique. Methods: Ninety-seven patients with osteoarthritis received a TKA using computer navigation. The tibial resection was performed according to the kinematic alignment (KA) principles, while the femoral rotation was set according to the gap-balancing technique. Preoperative MRIs and intraoperative resection depth data were used to calculate the following rotational axes: the transepicondylar axis (TEA), the posterior condylar axis (PCA) and the prosthetic posterior condylar axis (rPCA). The angles between the PCA and the TEA (PCA/TEA), between the rPCA and the PCA (rPCA/PCA) and between the rPCA and the TEA (rPCA/TEA) were measured. Data regarding patellar maltracking and PROMs were collected for 24 months postoperatively. Results: The mean PCA/TEA, rPCA/TEA and rPCA/PCA angles were −5.1° ± 2.1°, −4.8° ± 2.6° and −0.4° ± 1.7°, respectively (the negative values denote the internal rotation of the PCA to the TEA, rPCA to TEA and rPCA to PCA, respectively). There was no need for lateral release and no cases of patellar maltracking. Conclusions: A tibia-first, gap-balancing, “functional alignment” approach allows incorporating a gap-balancing technique with kinematic principles. Sagittal complexities in the proximal tibia (variable medial and lateral slopes) can be accounted for, as the tibial resection is completed prior to setting the femoral rotation. The prosthetic femoral rotation is internally rotated relative to the TEA, almost parallel to the PCA, similar to the femoral rotation of the KA-TKA technique. This technique did not result in patellar maltracking

Pre-operative clinical predictors for cardiology referral prior to total joint arthroplasty: the 'asymptomatic' patient

Background: No validated pre-operative cardiac risk stratification tool exists that is specific for total hip and total knee arthroplasty (THA and TKA, respectively). To reduce the risk of post-operative cardiac complication, surgeons need clear guidance on which patients are likely to benefit from pre-operative cardiac optimisation. This is particularly important for asymptomatic patients, where the need is harder to determine. Methods: Primary THA and TKA performed between January 1, 2010, and December 31, 2017, were identified from a single orthopaedic practice. Over 25 risk factors were evaluated as predictors for patients requiring additional cardiac investigation beyond an ECG and echocardiogram, and for cardiac abnormality detected upon additional investigation. A multivariate logistic regression was conducted using significant predictor variables identified from inferential statistics. A series of predictive scores were constructed and weighted to identify the influence of each variable on the ability to predict the detection of cardiac abnormality pre-operatively. Results: Three hundred seventy-four patients were eligible for inclusion. Increasing age (p < 0.001), history of cerebrovascular accident (p = 0.018), family history of cardiovascular disease (FHx of CVD) (p < 0.001) and decreased ejection fraction (EF) (p < 0.001) were significant predictors of additional cardiac investigation being required. Increasing age (p = 0.003), male gender (p = 0.042), FHx of CVD (p = 0.001) and a reduced EF (p < 0.001) were significantly predictive for the detection of cardiac abnormality upon additional cardiac investigation. Conclusions: Increasing age, male gender, FHx of CVD and decreased ejection fraction are important risk factors to consider for pre-operative cardiac optimisation in THA and TKA patients. These findings can be applied towards future predictive models, to determine which asymptomatic patients are likely to benefit from pre-operative cardiac referral

Experimental model of peri-prosthetic infection of the knee caused by Staphylococcus aureus using biomaterials representative of modern TKA

Prosthetic joint infection (PJI) following total knee arthroplasty (TKA) remains the leading cause for revision surgery, with Staphylococcus aureus the bacterium most frequently responsible. We describe a novel rat model of implant-associated S. aureus infection of the knee using orthopaedic materials relevant to modern TKA. Male Sprague-Dawley rats underwent unilateral knee implant surgery, which involved placement of a cementless, porous titanium implant into the femur, and an ultra-highly cross-linked polyethyelene (UHXLPE) implant into the proximal tibia within a mantle of gentamicin-laden bone cement. S. aureus biofilms were established on the surface of titanium implants prior to implantation into the femur of infected animals, whilst control animals received sterile implants. Compared to controls, the time taken to full weight-bear and recover pre-surgical body weight was greater in the infected group. Neutrophils and C-reactive protein levels were significantly higher in infected compared to control animals at day 5 post surgery, returning to baseline levels for the remainder of the 28-day experimental period. Blood cultures remained negative and additional plasma inflammatory markers were comparable for control and infected animals, consistent with the clinical presentation of delayed-onset PJI. S. aureus was recovered from joint tissue and implants at day 28 post surgery from all animals that received pre-seeded titanium implants, despite the use of antibiotic-laden cement. Persistent localised infection was associated with increased inflammatory responses and radiological changes in peri-implant tissue. The availability of a preclinical model that is reproducible based on the use of current TKA materials and consistent with clinical features of delayed-onset PJI will be valuable for evaluation of innovative therapeutic approaches

In vivo arthroscopic temperatures: a comparison between 2 types of radiofrequency ablation systems in arthroscopic anterior cruciate ligament reconstruction—a randomized controlled trial

Purpose: To compare a plasma ablation device with a standard ablation device in anterior cruciate ligament (ACL) reconstruction to determine which system is superior in terms of intra-articular heat generation and diathermy efficiency. Methods: This was a prospective, randomized controlled trial. The inclusion criteria were adult patients undergoing primary ACL reconstruction. Patients were randomized preoperatively to the standard ablation group or the plasma ablation group. A thermometer was inserted into the inferior suprapatellar pouch, and the temperature, time, and duration of radiofrequency ablation were measured continually. Results: No significant differences were found between the standard ablation system and the plasma ablation system for maximum temperature (29.77°C and 29.34°C, respectively; P =.95), mean temperature (26.16°C and 26.99°C, respectively; P =.44), minimum temperature (22.66°C and 23.94°C, respectively; P =.54), and baseline temperature (26.80°C and 27.93°C, respectively; P =.35). Similarly, no significant differences were found for operative time (82.90 minutes and 80.50 minutes, respectively; P =.72) and mean diathermy activation times (2.6 minutes for both systems; P =.90). The between-system coefficient of variation for the measured parameters ranged from 0.12% to 3.69%. No intra-articular readings above the temperature likely to damage chondrocytes were recorded. The mean irrigation fluid temperature had a significant correlation with the maximum temperature reached during the procedure (Spearman rank correlation, r = 0.87; P < .01). Conclusions: No difference in temperature was observed between the standard ablation and plasma ablation probes during ACL reconstruction. Temperatures did not exceed critical temperatures associated with chondrocyte death. Level of Evidence Level I, randomized controlled trial

Comparison of intra‑articular administration of adenosine, lidocaine and magnesium solution and tranexamic acid for alleviating postoperative inflammation and joint fibrosis in an experimental model of knee arthroplasty

Background: Dysregulated inflammatory responses are implicated in the pathogenesis of joint stiffness and arthrofibrosis following total knee arthroplasty (TKA). The purpose of this study was to compare the effects of intra-articular (IA) administration of tranexamic acid (TXA), an anti-fibrinolytic commonly used in TKA, and ALM chondroprotective solution on postoperative inflammation and joint tissue healing in a rat model of knee implant surgery. Methods: Male Sprague–Dawley rats (n = 24) were randomly divided into TXA or ALM treatment groups. The right knee of each rat was implanted with titanium (femur) and polyethylene (tibia) implants. An IA bolus (0.1 ml) of TXA or ALM was administered after implantation and capsule closure, and before skin closure. Postoperative coagulopathy, haematology and systemic inflammatory changes were assessed. Inflammatory and fibrotic markers were assessed in joint tissue, 28 days after surgery. Results: Haemostasis was comparable in animals treated with TXA or ALM after knee implant surgery. In contrast to ALM-treated animals, systemic inflammatory markers remained elevated at day 5 (IL-6, IL-12, IL-10, platelet count) and day 28 (IL-1β, IL-10) following surgery in TXA-treated animals. At day 28 following surgery, the extension range of motion of operated knees was 1.7-fold higher for ALM-treated animals compared to the TXA group. Key inflammatory mediators (NF-κB, IL-12, IL-2), immune cell infiltration (CD68+ cells) and markers of fibrosis (α-SMA, TGF-β) were also lower in capsular tissue of ALM-treated knees at day 28. Conclusion: Data suggest that IA administration of ALM is superior to TXA for reducing postoperative systemic and joint inflammation and promoting restoration of healthy joint tissue architecture in a rat model of TKA. Further studies are warranted to assess the clinical translational potential of ALM IA solution to improve patient outcomes following arthroplasty