Randa K. Elmallah

Dual mobility cups: an effective prosthesis in revision total hip arthroplasties for preventing dislocations

Purpose Postoperative dislocation is one of the most common complications following total hip arthroplasty (THA), and dual mobility articulations have been designed to provide greater hip stability. However, there are few studies that have assessed outcomes of these designs in revision THAs. Our purpose was to evaluate differences in dislocation rates, aseptic survivorship, and patient outcomes between dual mobility articulations and conventional arthroplasties in the revision setting. Methods Patients who underwent revision THA with dual mobility articulations (n = 60) were matched (1:2) to patients who had conventional single articulation prostheses (n = 120). They were matched for body mass index, age, gender, and Paprosky acetabular defect classification, and were followed up for a mean of 30 months (range, 18 to 52 months). The outcomes were evaluated preoperatively and at final follow-up using Harris Hip Scores, the University of California Los Angeles activity scale, and the Short Form-36 questionnaires. Results The dual mobility group had lower dislocation (1.7% (1 out of 60) versus 5.8% (7 out of 120)) and aseptic loosening rates (1.7% (1 out of 60) versus 4.2% (5 out of 120)) compared to the control group. There were no significant differences in functional outcomes, activity level, or overall physical and mental health status between the 2 cohorts. Conclusions When used in the revision setting, dual mobility bearings had fewer dislocations. We believe that these designs may lead to clinically significant improvements in complications while also improving patient reported and functional outcomes, but larger cohort studies are necessary for evaluation.

New and Common Perioperative Pain Management Techniques in Total Knee Arthroplasty

Optimal pain control in patients undergoing total knee arthroplasty (TKA) is imperative for good rehabilitation and functional outcomes. However, despite technological advancements, surgeons continue to struggle with adequate pain management in their patients. Current modalities in use, such as patient-controlled analgesia, opioids, and epidural anesthetics, provide good pain relief but can be associated with side effects and serious complications. As a result, newer pain control modalities have been used to try to reduce the use of opioids while providing adequate pain relief. Currently, there are no clear guidelines or evidence for an optimum postoperative TKA analgesic regimen. Our aim was to evaluate the recent literature and provide a summary of the newer perioperative analgesic modalities. Evidence suggests that analgesics, such as newer oral medications, peripheral nerve blocks, and periarticular injections, may improve pain management, rehabilitation, and patient satisfaction, as well as reduce opioid consumption. The literature has also highlighted that a multimodal approach to pain management may provide the best results. However, determining which modalities provide superior pain control is still being extensively studied, and further research is needed.

Predicting Blood Loss in Total Knee and Hip Arthroplasty

Marked blood loss during lower extremity total joint arthroplasties may lead to higher rates of transfusion, which may negatively affect surgical outcomes and yield greater complication rates. It is therefore ideal to identify factors that may increase the likelihood of blood loss, so they can be modified. From this review, it can be concluded that preoperative anemia, older age, multiple comorbidities, increased operative time, and use of postoperative anticoagulation may lead to higher blood loss and transfusion rates, although the influence of other factors remains controversial.

Liposomal Bupivacaine Suspension Can Reduce Lengths of Stay and Improve Discharge Status of Patients Undergoing Total Knee Arthroplasty

The purpose of this study was to use a large hospital database to assess: (1) length of hospital stay (LOS) and (2) discharge status among patients undergoing total knee arthroplasty (TKA) with or without the use of a liposomal bupivacaine suspension injection. We utilized an all-payer hospital administrative database from July 1, 2013 to June 30, 2014. We then selected patients age 18 years or older who had an inpatient stay for TKA in the data window based on International Classification of Diseases, Ninth Revision (ICD-9) procedure codes (ICD-9-CM = 81.54), which resulted in 103,152 TKA patients. Patients who had nerve blocks were excluded, which resulted in 94,828 TKA patients. The TKA cohort who received a liposomal bupivacaine suspension consisted of 14,668 patients (9,211 females; 5,457 males) who had a mean age of 66 years, while the TKAs without injections or block consisted of 80,160 patients (49,699 females; 30,461 males) who had a mean age of 66 years. Analyses of LOS were performed using a linear model, controlling for age, sex, race, region, Charlson index, and operating time. Discharge status to home versus rehabilitation or short-term nursing facility was evaluated using logistic regression analysis controlling for the above covariates. The adjusted mean LOS for the injection cohort was significantly shorter at 2.58 days compared with 2.98 days in the no injection cohort. The unadjusted distribution of patients being discharged to home compared with short-term nursing facility or rehabilitation was higher in the injection cohort compared with the cohort who did not receive injections (73.2 vs. 66.6%). Logistic regression analysis demonstrated that there was a higher likelihood of being discharged to home with liposomal bupivacaine. Patients who underwent TKA with liposomal bupivacaine had a significantly shorter LOS and a higher likelihood of being discharged to home. These results suggest that liposomal bupivacaine may represent a promising addition to current pain management regimens. Furthermore, it may limit pain following surgery, which may allow patients to ambulate earlier and have improved outcomes.

Robotic-assisted knee arthroplasty.

Robotics in total knee arthroplasty (TKA) has undergone vast improvements. Although some of the systems have fallen out of favor due to safety concerns, there has been recent increased interest for semi-active haptic robotic systems that provide intraoperative tactile feedback to the surgeon. The potential advantages include improvements in radiographic outcomes, reducing the incidence of mechanical axis malalignment of the lower extremity and better tissue balance. Proponents of robotic technology believe that these improvements may lead to superior functional outcomes and implant survivorship. We aim to discuss robotic technology development, outcomes of unicompartmental and total knee arthroplasty and the future outlook. Short-term follow-up studies on robotic-assisted knee arthroplasty suggest that, although some alignment objectives may have been achieved, more studies regarding functional outcomes are needed. Furthermore, studies evaluating the projected cost–benefit analyses of this new technology are needed before widespread adoption. Nevertheless, the short-term results warrant further evaluation.

The Effect of Comorbidities on Outcomes following Total Knee Arthroplasty

To enhance the success of total knee arthroplasty (TKA), clinicians must identify factors that may impede functional recovery. Multiple comorbidities may affect outcomes, and our purpose was to identify the role of overall disease burden, as well as individual comorbidities, on post-TKA outcomes. We prospectively reviewed 283 TKA patients (172 women, 111 men). Preexisting comorbidities were weighted using the Charlson comorbidity index (CCI). Patients were divided into four groups: CCI score of 0 to 1, 2, 3, or 4 or more and followed up at 6 weeks, 3 months, 1 year, and annually until 5 years. The most prevalent comorbidities were also individually assessed at these follow-ups. The effect of these on outcomes was evaluated using the Knee Society Score (KSS), Short Form 36 (SF-36), and lower extremity activity scale (LEAS). Patients who had lower CCI scores had significant improvements in KSS at 2- and 5-year follow-up (+34 and +38 points, respectively; p < 0.01). CCI scores of 0 to l demonstrated significantly greater improvement in the SF-36 physical component score (PCS) at final follow-up (+16 points; p < 0.05) and higher LEAS scores at 2 years postoperatively (p = 0.001), compared with the remaining cohorts. Endocrine disease and hypertension yielded significantly lower KSS at follow-up (-5 and -5 points, respectively; p < 0.05). Patients who had hypertension or gastrointestinal disease had significantly lower SF-36 PCS at final follow-up compared with those who did not (45 vs. 48 points and 47 vs. 49 points; p < 0.035 and 0.041, respectively), as well as lower activity scores (11 vs. 12 points for both comorbidities; p < 0.05). Patients who had cardiovascular disease had significantly lower SF-36 MCS (53 vs. 56 points, respectively; p = 0.03) at 4 years postoperatively than those without, as well as lower activity scores (11 vs. 12 points, respectively; p = 0.024). Patients who have lower CCIs may have improved activity and functional levels following TKA. Hypertension, cardiovascular disease, endocrine disease, and gastrointestinal disease may correlate with poorer functional and activity outcomes postoperatively.

Genetically modified chondrocytes expressing TGF-β1: a revolutionary treatment for articular cartilage damage?

Introduction: Currently, joint arthroplasty remains the only definitive management of osteoarthritis, while other treatment modalities only provide temporary and symptomatic relief. The use of genetically engineered chondrocytes is currently undergoing clinical trials. Specifically, it has been designed to induce cartilage growth and differentiation in patients with degenerative arthritis, with the aim to play a curative role in the disease process. Areas covered: This treatment involves the incorporation of TGF-β1, which has been determined to play an influential role in chondrogenesis and extracellular matrix synthesis. Using genetic manipulation and viral transduction, TGF-β1 is incorporated into human chondrocytes and administered in a minimally invasive fashion directly to the affected joint. Following a database literature search, we evaluated the current evidence on this product and its outcomes. Furthermore, we also briefly reviewed other treatments developed for chondrogenesis and cartilage regeneration for comparison. Expert opinion: This treatment method has sustained positive effects on functional outcomes and cartilage growth in initial trials. It allows administration in a minimally invasive manner that does not require extended recovery time. Although several treatment modalities are currently under investigation and appear promising, we hope that these effects can be sustained in further studies. Ultimately, we anticipate that the results may be reproducible in many clinical settings and allow us to effectively treat cartilage damage in patients with degenerative arthritis.

Rehabilitative Guidelines after Total Knee Arthroplasty: A Review.

Rehabilitation following total knee arthroplasty (TKA) continues to pose a challenge for both patients and providers. In addition, guidelines vary considerably between institutions, which often leave therapy regimens to the discretion of the provider. The lack of clear guidelines for rehabilitation may contribute to inadequate recovery of strength and range-of-motion, resulting in less optimal functional outcomes. Therefore, the aim of this review was to highlight and discuss a variety of post-TKA rehabilitative modalities currently available and to provide evidence regarding efficacy and practicality. Specifically, we assessed the role of and evidence for exercise therapy, aquatic therapy, balance training, continuous passive motion, cold therapy and compression, neuromuscular electrical stimulation, transcutaneous electrical nerve stimulation, and instrument-assisted soft-tissue therapy. Additionally, we proposed general recommendations for rehabilitation after TKA, and as we specifically described active and obese patients, we have included guidelines for these subsets as well. Our review examines the various rehabilitative modalities to offer suggestions for recovery of strength and range-of-motion after TKA, with a focus on the early incorporation of exercise therapy, balance training, aquatic therapy, cryopneumatic therapy, neuromuscular electrical stimulation, and transcutaneous electrical nerve stimulation. Dedication and commitment to rehabilitation may help patients attain and exceed their preoperative activity levels.

Liposomal Bupivacaine in Total Knee Arthroplasty for Better Postoperative Analgesic Outcome and Economic Benefits.

When orthopedists consider which analgesia to use after total knee arthroplasty (TKA), the primary objective is to relieve pain with fewer adverse side effects. Over the last decade, substantial efforts have been made to improve pain control following TKA, but it is still very challenging to obtain optimal control. Current modalities in use, such as opioids, epidurals, and nerve blocks, provide substantial pain relief, but they are associated with substantial side effects and serious complications. Recently, bupivacaine, a commonly used nonopioid analgesic, has been formulated into an aqueous suspension of multivesicular liposomes that provide long-lasting analgesia, while avoiding significant adverse effects of opioids. The purpose of this review is to analyze the use of traditional postsurgical pain management and the potential contribution of a long-acting liposomal formulation of bupivacaine as part of the analgesic regimen in TKA, including its mode of action, injection technique, efficacy on pain, and health care costs.

A current review of core decompression in the treatment of osteonecrosis of the femoral head.

The review describes the following: (1) how traditional core decompression is performed, (2) adjunctive treatments, (3) multiple percutaneous drilling technique, and (4) the overall outcomes of these procedures. Core decompression has optimal outcomes when used in the earliest, precollapse disease stages. More recent studies have reported excellent outcomes with percutaneous drilling. Furthermore, adjunct treatment methods combining core decompression with growth factors, bone morphogenic proteins, stem cells, and bone grafting have demonstrated positive results; however, larger randomized trial is needed to evaluate their overall efficacy.