Total knee arthroplasty (TKA) is one of the most highly successful orthopaedic procedures performed in North America. It is also one of the most common procedures performed, and its incidence ...continues to increase. Despite this, it is the opinion of many that patients of advanced age groups are not ideal candidates to undergo such procedures secondary to the concern over higher complication rates and poorer functional outcomes. This review article attempts to analyze the current body of literature concerning TKA outcomes and to evaluate some of the issues that are more specific to this population when they undergo TKA. It is our hypothesis that the literature does not support this popular misconception, and that older patients who do not have significant medical comorbidities are good candidates to undergo primary TKA. However, certain cohorts of this population are not ideal candidates to undergo this procedure. Also, certain joint reconstructive procedures, such as simultaneous and staged bilateral TKA, are higher risk procedures in this patient cohort.
Ileus following total knee arthroplasty is a clinically and financially significant postoperative complication that has not been extensively described in the orthopaedic joint literature. Ileus has ...been found to occur in 0.7 to 4.0% of patients after total joint arthroplasty. In a 17-year period (2001 fiscal year through 2017 fiscal year) at one institution, we found an incidence of 0.500% (190/38,007) following knee arthroplasty. In addition, the incidence of ileus following total knee arthroplasty (TKA) has drastically declined over this 17-year period, from 1.593% (13/816) in 2001 to 0.120% (4/3,332) in 2017. This decrease may be attributed to a reduction in narcotic use postoperatively, earlier ambulation following surgery, and reduction in length of hospital stay. Though postoperative ileus is not yet a preventable complication, recognition of risk factors may permit earlier intervention to ameliorate some of the morbidity associated with this condition.
Periarticular injections (PAIs) and adductor canal blocks (ACBs) are widely accepted pain management strategies for total knee arthroplasty (TKA); however, the optimal anesthetic concentration to ...provide adequate pain relief while avoiding toxicity remains controversial. The purpose of this study is to evaluate the efficacy of different anesthetic concentrations for PAI alone and in combination with ACB.
This retrospective cohort study of patients undergoing primary TKAs between January 2019 and November 2020 included 3 groups: 0.25% PAI (50 cc of 0.25% bupivacaine PAI diluted with 50 cc of saline and ketorolac), 0.5% PAI (50 cc of 0.5% bupivacaine with 50 cc of saline and ketorolac), and PAI + ACB (ultrasound-guided preoperative anesthesiologist-administered ACB and 0.25% PAI).
In total, 368 TKAs were analyzed (123 0.25%, 132 0.5%, and 113 PAI + ACB). Total overall hospital narcotic usage in oral morphine equivalents (OME) was significantly lower for the 0.5% group (120.09 vs 165.26 and 175.75) compared to the 0.25% and PAI + ACB groups, respectively (P < .0001). Cumulative OME for the first 3 shifts was also lower for 0.5% (68.7 vs 83.7 and 76.4) compared to the 0.25% and PAI + ACB groups, respectively (P = .030). Total postoperative narcotics in OME were significantly lower for 0.5% (617.9 vs 825.2 and 1047.6) than 0.25% and PAI + ACB, respectively (P = .0003). Number of prescriptions within 6 weeks postoperatively were also significantly lower for 0.5% (1.7) than 0.25% (2.1) and PAI + ACB (2.4) (P = .0003).
Patients receiving 0.5% PAI had lower narcotic usage compared to 0.25% PAI or PAI + ACB. ACB may be eliminated without compromising pain control if the dose of local anesthetic in the PAI is sufficiently high.
Leg pain associated with walking is sometimes incorrectly attributed to hip osteoarthritis (OA) or lumbar spinal stenosis (LSS).
This study compared physicians' values of signs and symptoms for ...diagnosing and differentiating hip OA and LSS to their clinical utility.
Musculoskeletal physicians were surveyed with online questionnaires. Patients were recruited from hip and spine specialty practices.
Seventy-seven hip OA and 79 LSS patients.
Signs and symptoms of hip OA and LSS.
Fifty-one of 66 invited musculoskeletal physicians completed online surveys about the values of 83 signs and symptoms for diagnosing hip OA and LSS. Of these, the most valued 32 symptoms and 13 physical examination items were applied to patients with symptomatic hip OA or LSS. Positive likelihood ratios (+LR) were calculated for each items' ability to differentiate hip OA from LSS, with a +LR>2 set as indicating usefulness for favoring either diagnosis. Positive LRs were compared with surveyed physicians' values for each test.
All symptoms were reported by some patients with each diagnosis. Only 11 of 32 physician-valued symptoms were useful for discriminating hip OA from LSS. Eight symptoms favored hip OA over LSS: groin pain (+LR=4.9); knee pain (+LR=2.2); pain that decreased with continued walking (+LR=3.9); pain that occurs immediately with walking (+LR=2.4); pain that occurs immediately with standing (+LR=2.1); pain getting in/out of a car (+LR=3.3); pain with dressing the symptomatic leg (+LR=3.1); and difficulty reaching the foot of the symptomatic leg while dressing (+LR=2.3). Three symptoms favored LSS over hip OA: pain below the knee (+LR=2.3); leg tingling and/or numbness (+LR=2.7); and some pain in both legs (+LR=2.5). Notable symptoms that did not discriminate hip OA from LSS included: pain is less while pushing a shopping cart (+LR=1.0); back pain (+LR=1.1); weakness and/or heaviness of leg (+LR=1.1); buttocks pain (+LR=1.2); poor balance or unsteadiness (+LR=1.2); pain that increased with weight-bearing on the painful leg (+LR=1.3), and step to gait on stairs (+LR=1.7). Consistent with physicians' expectations, 7 of 13 physical examination items strongly favored hip OA over LSS: limited weight-bearing on painful leg when standing (+LR=10); observed limp (+LR=9); and painful and restricted range-of-motion with any of five hip maneuvers (+LR range 21–99). Four of five tested neurological deficits (+LR range 3–8) favored the diagnosis of LSS over hip OA.
There is substantial crossover of symptoms between hip OA and LSS, with some physician-valued symptoms useful for differentiating these disorders whereas others were not. Physicians recognize the value of the examination of gait, the hip, and lower extremity neurological function for differentiating hip OA from LSS. These tests should be routinely performed on all patients for which either diagnosis is considered. Awareness of these findings might reduce diagnostic errors.
Abstract Background Intraoperative femur fracture (IFF) is a well-known complication in primary uncemented total hip arthroplasty (THA). Variations in implant instrumentation design and operative ...technique may influence the risk of IFF. This study investigates IFF between a standard uncemented tapered-wedge femoral stem and its second generation successor with the following design changes: size specific medial curvature, proportional incremental stem growth, modest reduction in stem length, and distal lateral relief. Methods A single experienced surgeon’s patient database was retrospectively queried for IFF occurring during primary uncemented THA using a standard tapered-wedge femoral stem system or a second generation stem. All procedures were performed using soft tissue preserving anatomic capsule repair and posterior approach. The primary outcome measure was IFF. A z-test of proportions was performed to determine significant difference between the two stems with respect to IFF. Patient demographics, Dorr classification, and implant characteristics were also examined. Results Forty one of 1510 patients (2.72%) who received a standard tapered-wedge femoral stem sustained an IFF, whereas 5 of 800 patients (0.63%) using the second generation stem incurred an IFF. No other significant associations were found. Conclusion A standard tapered-wedge femoral stem instrumentation system resulted in greater than four times higher incidence of IFF than its second generation successor used for primary uncemented THA. Identifying risk factors for IFF is necessary to facilitate implant system improvements and thus maximize patient outcomes.
While femoral intramedullary alignment has been found to be the most accurate and reproducible method for proper femoral component orientation in total knee arthroplasty, certain situations preclude ...the use of intramedullary alignment, such as ipsilateral long-stem total hip arthroplasty, femoral shaft deformity (congenital or post-traumatic), capacious femoral canal, and retained hardware. These cases require alternative alignment guides, that is, extramedullary alignment. The purpose of this study was to determine the accuracy of intramedullary alignment in reproducing the femoral anatomic axis. Using 35 adult cadaveric femora without obvious clinical deformity, and 7 with proximal prosthetic devices blocking the passage of an intramedullary guide, the accuracy of the guide rod was assessed both anatomically and radiographically. In the seven femora with proximal femoral devices, the guide rod could not be completely seated, resulting in a greater degree of flexion of the guide rod compared with the mechanical axis of the femur, and a greater degree of varus compared with the anatomical axis, as compared with 35 femora without obvious deformity. In cases where seating of the intramedullary guide rod is either incomplete or impossible, extramedullary femoral guides allow more accurate determination of the distal femoral cut by referencing directly from the mechanical axis, that is, the center of the femoral head. We present case studies as examples of indications for use of an extramedullary femoral guide. In addition, we demonstrate two different techniques for extramedullary femoral alignment using fluoroscopic guidance in cases incompatible with intramedullary alignment.
Despite the most recent American Academy of Orthopaedic Surgeons clinical practice guideline making a "strong" recommendation against the use of intraoperative navigation in total knee arthroplasty ...(TKA), its use is increasing. We utilized the concept of the reverse fragility index (RFI) to assess the strength of neutrality of the randomized controlled trials (RCTs) comparing the long-term survivorship of computer-navigated and conventional TKA.
A systematic review was performed including all RCTs through August 3, 2021, comparing the long-term outcomes of computer-navigated and conventional TKA. Randomized trials with mean follow-up of >8 years and survivorship with revision as the end point were included. The RFI quantifies the strength of a study's neutrality by calculating the minimum number of events necessary to flip the result from nonsignificant to significant. The RFI at a threshold of p < 0.05 was calculated for each study reporting nonsignificant results. The reverse fragility quotient (RFQ) was calculated by dividing the RFI by the study sample size.
Ten clinical trials with 2,518 patients and 38 all-cause revisions were analyzed. All 10 studies reported nonsignificant results. The median RFI at the p < 0.05 threshold was 4, meaning that a median of 4 events would be needed to change the results from nonsignificant to significant. The median RFQ was 0.029, indicating that the nonsignificance of the results was contingent on only 2.9 events per 100 participants. The median loss to follow-up was 27 patients. In all studies, the number of patients lost to follow-up was greater than the RFI.
The equipoise in long-term survivorship between computer-navigated and conventional TKA rests on fragile studies, as their statistical nonsignificance could be reversed by changing the outcome status of only a handful of patients--a number that was always smaller than the number lost to follow-up. Routine reporting of the RFI in trials with nonsignificant findings may provide readers with a measure of confidence in the neutrality of the results.
Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.
Failure due to trunnionosis with adverse local tissue reaction (ALTR) has been reported with cobalt-chrome (CoCr) heads in total hip arthroplasty (THA); however, there are limited data on the use of ...these heads in the revision setting. The purpose of this study was to analyze the outcomes of patients who underwent revision THA with a retained femoral component and received a CoCr femoral head on a used trunnion.
In this retrospective review, we identified all patients who underwent revision THA with a retained femoral component and received a CoCr femoral head between February 2006 and March 2014. Demographic factors, implant details, and postoperative complications, including the need for repeat revisions, were recorded. In total, 107 patients were included (mean age 67 years, 74.0% women). Of the 107 patients, 24 (22.4%) required repeat revisions.
Patients who required repeat revision were younger than those who did not (mean age: 62.9 versus 69, P = .03). The most common indications for repeat revision were instability (8 of 24, 33.3%), ALTR (5 of 24, 20.8%), and infection (4 of 18, 16.7%). Evidence of ALTR or metallosis was identified at the time of reoperation in 10 of the 24 patients who underwent re-revision (41.7%).
The placement of a new CoCr femoral head on a used trunnion during revision THA with a retained femoral component carries a significant risk of complication (22.4%) and should be avoided when possible.
During cruciate retaining (CR) total knee arthroplasty (TKA), the posterior cruciate ligament (PCL) may avulse at its insertion. The incidence of PCL avulsion fracture has not been previously ...studied. The aim of this study is to report on the incidence and clinical significance of intraoperative PCL avulsion during primary CR TKA and to identify potential risk factors. Our institutional joint registry was retrospectively reviewed for PCL avulsion occurring during CR TKA implanted between April 2008 and April 2016. Patient demographics, preoperative range of motion (ROM), complications, and revision rate were examined. A control group of 132 patients was used for comparison to identify potential risk factors. Forty-four of 2,457 patients (1.7%) suffered a PCL avulsion fracture during primary CR TKA. No intraoperative repair was performed and no postoperative weight bearing or ROM restrictions were implemented. There was no significant difference in BMI (
= 0.258), mean preoperative ROM (
= 0.763), or femoral and tibial component sizes (
= 0.3069,
= 0.1306) between groups. Logistic regression found female gender (
= 0.0254) to be the only statistically significant risk factor for PCL avulsion. The incidence of intraoperative PCL avulsion fracture during CR TKA is low (1.7%) and does not appear to affect postoperative ROM, subjective stability, or incidence of revision. Female gender was identified as the only patient factor that increased the risk of PCL avulsion fracture.
Abstract Modular neck stems allow for optimization of joint biomechanics by restoring anteversion, offset, and limb length. A potential disadvantage is the generation of metal ions from fretting and ...crevice corrosion. We identified 118 total hip arthroplasty implanted with one type of dual-modular femoral component. Thirty-six required revision due to adverse local tissue reaction. Multivariate analysis isolated females and low offset necks as risk factors for failure. Kaplan–Meir analysis revealed small stem sizes failed at a higher rate during early follow-up period. Although the cobalt/chrome levels were higher in the failed group, these tests had low diagnostic accuracy for ALTR, while MRI scan was more sensitive. We conclude that the complications related to the use of dual modular stems of this design outweigh the potential benefits.
