Weight change 1 year following total knee or hip arthroplasty

BACKGROUND: Pain secondary to osteoarthritis (OA) of the hip or knee is often used as a reason to not lose weight prior to total knee or hip arthroplasty (TKA, THA). This study followed the weight change of patients who subjectively increased their activity levels 1 year following TKA or THA. METHODS: We reviewed the records and prospectively followed the weight of 84 patients 1 year following surgery. The pre and postoperative weight were compared, including separate 10 kg categories (e.g. 60.1-70.0 kg). RESULTS: All patients had improved mobility as evaluated by either the clinical notes or a patient-based questionnaire. At 1 year, there was no significant change in weight; only an insignificant small increase in weight was seen. CONCLUSIONS: This study suggests that lower preoperative activity levels are not the cause for the inability to lose weight or that the gain in mobility achieved by joint replacement, of its own, does not result in weight loss.     

Patient-reported outcomes after total hip and knee arthroplasty: comparison of midterm results

The aim of this study was to compare the midterm functional outcomes of total knee arthroplasty (TKA) and total hip arthroplasty (THA). A cross-sectional postal audit survey of all consecutive patients who had a primary joint replacement at one orthopedic center 5 to 8 years ago was conducted. Participants completed an Oxford hip score or Oxford knee score, which are self-report measures of functional ability. Completed questionnaires were returned from 1112 THA patients and 613 TKA patients, giving a response rate of 72%. The median Oxford knee score of 26 was significantly worse than the median Oxford hip score of 19 (P < .001). In conclusion, TKA patients experience a significantly poorer functional outcome than THA patients 5 to 8 years postoperatively.     

Comparison of total hip and knee arthroplasty cohorts and short-term outcomes from a single-center joint registry

The purpose of this study was to compare short-term clinical outcomes between total hip arthroplasty (THA) and total knee arthroplasty (TKA) patient cohorts, adjusting for confounding variables including age, sex, body mass index, operative time, length of stay, and preoperative Western Ontario and McMaster Universities and 12-Item Short-Form Health Survey. A total of 349 patients who met inclusion and exclusion criteria created 2 cohorts: THA, 194, and TKA, 155, for statistical analysis via multiple regression and analysis of covariance measures. Outcome measures included Western Ontario and McMaster Universities and 12-Item Short-Form Health Survey data, collected prospectively at baseline and 2 years of follow-up. The current study showed that baseline characteristics of TKA patients have more factors with negative effect on postoperative outcome than THA. However, despite controlling for the possible confounding effect of these variables, THA patients experienced a significantly better functional outcome than TKA patients.     

Financial impact of a capitation matrix system on total knee and total hip arthroplasty

Total hip and total knee arthroplasty are high-volume surgical procedures that have a substantial economic impact for the healthcare system. This study analyzes the financial effect of a capitation matrix system on total knee and total hip implant costs over a 1-year period at a community hospital system. The matrix implant levels were based on implant characteristics, correlating increased technological sophistication of the various implants with increased but capitated payment to vendors. In the first year after the implementation of the matrix system, implant costs for the hospital decreased by 26.1% per implant for 369 total hip procedures and also by 26.1% per implant for 934 total knee procedures.     

Quality of life outcomes in revision vs primary total hip arthroplasty: a prospective cohort study

This study included 143 patients who had revision total hip arthroplasty (THA) and 144 patients who had primary THA. The primary outcome variable in this study was the Western Ontario and McMaster Universities Osteoarthritis Index scores. Univariate and multivariate regression models were used to assess the relationship between surgical procedure and postoperative health related quality of life outcomes. The mean follow-up period was 1.7 years (range, 1-3 years). The mean preoperative function of patients with primary THA was significantly worse than that in the revision group (delta = -6.2; P = .013). Postoperative functional outcome was significantly better in patients with primary THA (delta = 6.5, P = .016) than in patients who had revision THA. The magnitude of improvement in quality of life is greater for the patient with primary THA in comparison to the patient with revision THA.     

Conversion total hip arthroplasty: Primary or revision total hip arthroplasty

Total hip arthroplasty (THA) is an increasingly common procedure among elderly individuals. Although conversion THA is currently bundled in a diagnosis related group (DRG) with primary THA, there is a lack of literature supporting this classification and it has yet to be identified whether conversion THA better resembles primary or revision THA. This editorial analyzed the intraoperative and postoperative factors and functional outcomes following conversion THA, primary THA, and revision THA to understand whether the characteristics of conversion THA resemble one procedure or the other, or are possibly somewhere in between. The analysis revealed that conversion THA requires more resources both intraoperatively and postoperatively than primary THA. Furthermore, patients undergoing conversion THA present with poorer functional outcomes in the long run. Patients undergoing conversion THA better resemble revision THA patients than primary THA patients. As such, patients undergoing conversion THA should not be likened to patients undergoing primary THA when determining risk stratification and reimbursement rates. Conversion THA procedures should be planned accordingly with proper anticipation of the greater needs both in the operating room, and for in-patient and follow-up care. We suggest that conversion THA be reclassified in the same DRG with revision THA as opposed to primary THA as a step towards better allocation of healthcare resources for conversion hip arthroplasties.     

Epidemiology and risk factors for perioperative mortality after total hip and knee arthroplasty

The perioperative mortality of total knee and hip arthroplasties (TKA, THA) remains a major concern among health care providers and their patients. The increase in utilization of TKA and THA makes it imperative to be aware of factors that are associated with this unfortunate event. Therefore we analyzed the Nationwide Inpatient Sample data from 1998 to 2008 and compared admissions with perioperative mortality to those that survived their hospitalization. An estimated total of 4,438,213 TKA and 2,182,121 THA procedures were performed in the United States between 1998 and 2008. The average mortality rate for TKA was 0.13% and 0.18% for THA, or 0.34 and 0.44 events per 1,000 inpatient days, respectively. Independent risk factors for in‐hospital mortality were advanced age, male gender, ethnic minority background, emergency admission as well as a number of comorbidities and complications. Furthermore, we demonstrated that the timing of death occurred earlier after TKA when compared to THA, with 50% of fatalities occurring by day 4 versus day 6 of the hospitalization, respectively. This study provides nationally representative information on risk factors for and timing of perioperative mortality after TKA and THA. Our data can be used to assess the risk for perioperative mortality and to develop targeted intervention to decrease such risk. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1811–1821, 2012     

Dislocation following primary posterior-stabilized total knee arthroplasty

From 1981 through 1991, 3, 032 primary total knee arthroplasties were performed using the Insall-Burstein Posterior Stabilized Condylar Prosthesis (IB-I, IB-II, and IB-II modified) (Zimmer, Warsaw, IN). Fifteen posterior dislocations occurred: 4 with the IB-I system occurring 2 or more years after surgery, 10 with the IB-II system (8 occurring 6 months after surgery and 2 occurring 2–3 years after surgery), and 1 with the IB-II modified system occurring 9 months after surgery. Statistically significant differences for the rate of dislocation between both the IB-I and IB-II modified arthroplasties versus the IB-II arthroplasties were found (P < .001). In an attempt to identify a cause for these dislocations, the authors retrospectively assessed the 15 dislocated cases with respect to sex, age, weight, height, preoperative and postoperative Hospital for Special Surgery scores, preoperative and postoperative alignment, preoperative versus postoperative reconstruction dimensions, patellar thickness and height, and postoperative flexion and compared the results with those patients who did not experience dislocation. Possible etiologies and mechanisms of dislocation were sought. There were no significant differences between the control and study groups for any variable assessed, with the exception of postoperative flexion, which averaged 118° for the study group and 105° for the control group (P < .001). Conservative management was successful in 11 cases. In September 1988 the IB-II system was introduced; modification of the tibial insert was made in January 1990. The 10 IB-II dislocations occurred prior to the modification of the modular tibial polyethylene insert, and the 3 recurrent dislocations in this group were successfully treated with revision to this modified insert. Since this modification, 656 IB-II modified systems have been implanted with one dislocation (0.15%).     

Bypassing the post-anaesthesia care unit after elective hip and knee arthroplasty: a prospective cohort safety study

Following knee and hip arthroplasty, transfer to a recovery area immediately following surgery and before going to ward might be unnecessary in low-risk patients. Avoiding the recovery area in this way could allow for more targeted use of resources for higher risk patients, which may improve operating theatre flow and productivity. A prospective single-centre cohort study on the safety of criteria for bypassing the post-anaesthesia care unit in elective hip and knee arthroplasty was designed. Criteria were: ASA physical status < 3; peri-operative bleeding < 500 ml; low postoperative discharge-score (modified Aldrete-score); and an uncomplicated surgical and neuraxial anaesthesia procedure. The primary outcome was the number of patients in need of secondary readmission to the post-anaesthesia care unit. Events within the first 24 postoperative hours were recorded, along with readmission and complication rates. A total of 696 patients were included, with 287 (41%) undergoing total hip arthroplasty, 274 (39%) undergoing total knee arthroplasty and 135 (19%) undergoing unicompartmental knee-arthroplasty. Of these, 207 (44%) bypassed the post-anaesthesia care unit. Patients all received multimodal analgesia without peripheral nerve blockade. Only one patient in the ward group required secondary readmission to the post-anaesthesia care unit. Within 24 h, 151 events were reported, with 41 (27%) in the ward group and 110 (73%) in the post-anaesthesia care unit group. Two events in each group occurred within 2 hours of surgery. No complications were attributed to bypassing the post-anaesthesia care unit. The use of simple pragmatic criteria for bypassing the post-anaesthesia care unit for patients undergoing knee and hip arthroplasty with spinal anaesthesia is possible and associated with significant reduction of post-anaesthesia care unit admission and without apparent safety issues. Confirmation is needed from other studies and external validity should be interpreted cautiously in centres with different peri-operative regimens, organisational and staffing structures.     

A systematic review of pain outcomes reported by randomised trials of hip and knee arthroplasty

It is difficult to pool results from randomised clinical trials that report different outcomes. We want to develop a core set of pain-related outcomes after total hip or knee arthroplasty, the first stage of which is to systematically review published outcomes. We searched PubMed, Embase and CENTRAL for relevant trials to January 2020. We identified 165 outcomes from 565 trials with 50,668 participants, which we categorised into six domains: pain; analgesic consumption; quality of care; adverse events; mobility; and patient-reported outcome measures. The outcome in each domain reported by most trials was: visual analogue score for pain, 401 (71%); morphine consumption, 212 (38%); length of hospital stay, 166 (29%); nausea or vomiting, 425 (75%); range of motion, 173 (31%); and patient satisfaction score, 181 (32%). A primary outcome was reported in 281 (50%) trials: 101 (18%) trials reported consumption of rescue analgesics and 95 (17%) trials reported pain. We plan to publish a consensus on outcomes that should be reported in postoperative pain trials after hip or knee arthroplasty.     

Results of total hip and total knee arthroplasties in patients with synovial chondromatosis

This retrospective analysis examines the outcome of total joint arthroplasty for severe arthritis in patients with synovial chondromatosis. All 11 patients treated with total hip arthroplasty (n = 7) or total knee arthroplasty (n = 4) returned for follow-up at a mean of 10.8 years after surgery. Pain and functional scores improved significantly in all patients. Knee range of motion improved in all patients. Synovial chondromatosis recurred in 1 knee (25%) and 1 hip (14%). Total joint arthroplasty is a valuable treatment option for these patients with predictable improvement in pain and function. Knee range of motion is likely to improve but may be less than expected for primary total knee arthroplasty. Patients remain at risk for recurrence.     

Outcomes of total hip and knee arthroplasty after cardiac transplantation

The outcomes of 18 primary or revision total hip (THA) and knee arthroplasties (TKA) in 9 patients with cardiac transplants were reviewed. Primary total joint arthroplasties were performed for osteonecrosis (5 hips) or osteoarthritis (5 hips, 4 knees). There were no infections in any of these patients. Final Harris Hip Scores were 71.8 for patients with osteonecrosis and 88.6 for osteoarthritis. Eight of 10 hips were pain-free at final follow-up. Two of the 10 primary THAs required late revision at 7 and 10 years after the index arthroplasty. One patient (2 hips and 1 knee) had chronic bilateral lower extremity pain. Total knee arthroplasty range of motion averaged from 7.5° to 118°. Average final Knee Society function score was 79, and objective score was 88. One of 4 patients with primary TKA required a manipulation under anesthesia. No reoperations were required in this group. Overall, patients with heart transplantations on immunosuppression had generally good pain relief after THA and TKA. There were no infections in this small cohort; however, there were many complications.     

Alignment of computer-assisted total knee arthroplasty in patients with altered hip center

This study aimed to determine limb and component alignment after computer-assisted total knee arthroplasty in 30 patients (32 limbs) with an altered hip center due to a prior hip implant or deformed femoral head. There were no outliers greater than ±3° in the postoperative coronal alignment of the limb and the femoral component in relation to the altered hip center. Two limbs (8%) were more than ±3° for coronal alignment of the femoral component in relation to the anatomical hip center and 96% of limbs had less than 2° deviation in relation to the altered hip center. Computer-navigated total knee arthroplasty results in accurate restoration of lower limb and component alignment in patients with prior hip implants or deformed femoral heads where accurate restoration of alignment may be challenging due to altered hip center.     

Improved clinical outcomes after high-flexion total knee arthroplasty: a 5-year follow-up study

The purpose of this study was to determine if high-flexion total knee arthroplasty resulted in improved outcomes compared with conventional total knee arthroplasty. This was a prospective, double-blind, randomized controlled trial involving 76 patients over 5 years. We compared the postoperative flexion range, Knee Society scores, Oxford knee scores, and SF-36 scores between 2 groups. The high-flexion group was able to achieve a significant sustainable increase in postoperative knee flexion angle; and this correlated to a significant improvement in the General Health, Vitality, and Physical Functioning scales of SF-36 at 5 years postoperatively. Our results signify that high-flexion total knee arthroplasty has additional benefits to the quality of life in patients who require higher degrees of knee flexion in their activities of daily living.     

Mental health and outcomes in primary total joint arthroplasty

A consecutive series of 640 total joint arthroplasty patients was interviewed before surgery and at a minimum of 2 years following surgery. Statistical analyses were conducted to examine the effect of psychological distress and other patient characteristics on outcomes (Western Ontario and McMaster Universities Osteoarthritis Index, Short Form 36, and Quality of Well-Being index). Before and after surgery, distressed subjects had significantly lower scores than nondistressed subjects for most dependent measures (P range, .05 ≤ .001). All mean outcomes improved by follow-up in both groups (P ≤ .001) except mental health scores of nondistressed subjects. Stepwise regression analysis found that low baseline mental health score, non-Hispanic ethnicity, and fewer years since procedure were the strongest predictors of worse Western Ontario and McMaster Universities Osteoarthritis Index scores at follow-up. Although the magnitude of improvement is similar to nondistressed subjects, distressed patients do not achieve comparable functional and psychosocial outcomes.     

全髋关节置换术治疗僵直髋的临床疗效

目的探讨僵直髋患者行全髋关节置换术(THA)的临床疗效。方法采用THA治疗16例僵直髋患者(21髋),比较手术前后髋关节被动屈曲度、Harris评分。结果患者手术均顺利完成。16例患者均获得随访,时间6个月~3年。未出现术后切口感染、脂肪栓塞、下肢静脉血栓、假体松动等并发症。末次随访时,被动屈曲度由术前0°提高至62°~96°(76.5°±8.3°)(P<0.01);Harris评分由术前14~38(27.2±2.8)分提高至67~92(84.1±6.5)分(P<0.01);髋关节功能:优8髋,良9髋,可3髋,差1髋,优良率17/21。结论THA治疗僵直髋,能够减轻髋关节疼痛,增加髋关节活动度,改善髋关节功能,提高患者的生活质量。术前的充分准备及丰富的手术经验是手术成功的关键。     

Metal hypersensitivity in total hip and knee arthroplasty: Current concepts

Metal hypersensitivity (MHS) is a rare complication of total joint arthroplasty that has been linked to prosthetic device failure when other potential causes have been ruled out. The purpose of this review was to conduct an analysis of existing literature in order to get a better understanding of the pathophysiology, presentation, diagnosis, and management of MHS. It has been described as a type IV hypersensitivity reaction to the metals comprising prosthetic implants, often nickel and cobalt-chromium. Patients suffering from this condition have reported periprosthetic joint pain and swelling as well as cutaneous, eczematous dermatitis. There is no standard for diagnosis MHS, but tests such as patch testing and lymphocyte transformation testing have demonstrated utility, among others. Treatment options that have demonstrated success include administration of steroids and revision surgery, in which the existing metal implant is replaced with one of less allergenic materials. Moreover, the definitive resolution of symptoms has most commonly required revision surgery with the use of different implants. However, more studies are needed in order to understand the complexity of this subject.     

Assessing short-term functional outcomes and knee alignment of computer-assisted navigated total knee arthroplasty

This retrospective study examined the relationship between the mechanical axis of the knee throughout its functional arc and functional outcomes in patients with computer-assisted navigation total knee arthroplasty. Data on final intraoperative functional arc alignment were obtained on 76 patients who had computer-assisted navigation total knee arthroplasty over a 2-year period and correlated with scores from postoperative Short Form 12 and Western Ontario and McMaster Universities functional outcome surveys. No correlation was found between functional arc alignment and outcomes from Western Ontario and McMaster Universities or Short Form 12 surveys; however, subgroup analysis of patients with more than 3° average final intraoperative alignment throughout the functional arc of motion demonstrated increased difficulty with daily activities (P = .05). The results indicate that patients with more than 3° average alignment throughout the functional arc of motion perform more poorly with daily activities postoperatively.     

Preoperative risk factors for postoperative cardiac arrest following primary total hip and knee arthroplasty: A large database study

BackgroundCardiac arrest (CA) has been identified as a potential complication following Total Hip Arthroplasty (THA) and Total Knee Arthroplasty (TKA). This retrospective, case-controlled study aims to identify risk factors in order to improve the management of patients undergoing THA or TKA with known preoperative comorbidities.MethodsCPT codes were used to investigate the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database for patients who underwent THA or TKA from 2010 to 2017. Patients were classified as having cardiac arrest (CA) by the NSQIP guidelines. Patient samples with all possible covariates were included for the multivariate logistic regression analysis and assessed for independent association.ResultsPatients receiving perioperative transfusion, experiencing dyspnea with moderate exertion, dyspnea at rest, patients currently on dialysis, and patients aged ≥72 are all independently associated with increased rates of cardiac arrest (CA) following THA. Patients receiving perioperative transfusion, patients with anemia, bleeding disorders, dyspnea with moderate exertion, cardiac comorbidities, pulmonary comorbidities, and patients aged ≥73 are all associated with increased rates of cardiac arrest (CA) following TKA.ConclusionPatients with the identified risk factors are at a greater risk of suffering cardiac arrest within 30 days following THA and TKA. It is imperative that we recognize which risk factors may precipitate CA in THA and TKA recipients so that prophylactic management can be employed. Furthermore, management guidelines should be updated for patients at high risk of CA following THA and TKA to prevent this complication.