2018 John N. Insall Award: Recovery of Knee Flexion With Unsupervised Home Exercise Is Not Inferior to Outpatient Physical Therapy After TKA: A Randomized Trial.

BACKGROUND: Concerns about the cost and convenience of postsurgical physical therapy (PT) have sparked interest in unsupervised, home-based rehabilitation. However, the effectiveness of unsupervised home exercise after primary TKA has not been previously evaluated. QUESTIONS/PURPOSES: (1) Can unsupervised home exercise after surgery provide noninferior recovery of passive knee flexion compared with formal outpatient PT? (2) Does a web-based platform for home-based exercise provide an advantage compared with a printed PT manual? METHODS: We conducted a randomized, noninferiority trial involving 290 patients (20% of the 1464 eligible patients who could be contacted) who underwent primary TKA from March 2016 to April 2018. We included patients > 18 years old who were undergoing primary, unilateral TKA and provided written consent. We excluded patients with preoperative knee flexion < 90°, patients considering surgical intervention in a hip or the contralateral knee, patients discharged to an extended care facility, and revision or conversion TKA. We randomized patients to one of three groups: outpatient PT, unsupervised home exercise using a web-based platform (web PT), or unsupervised home exercise using a printed paper manual (paper PT). We also implemented a "delayed recovery intervention" within the home exercise program, in which patients were obliged to begin outpatient PT if knee flexion was < 70° at 2 weeks or < 90° at 4 weeks. The primary outcome was change in knee flexion from preoperative baseline after 4 to 6 weeks and 6 months. Secondary outcomes included Knee Injury and Osteoarthritis Outcome Score (KOOS), time back to activities of daily living, and time off narcotics. All analyses were intention to treat, and the noninferiority margin was 5% with maximum flexion as the outcome of interest for this parameter. RESULTS: Adjusted differences in change in passive flexion for web PT +3° (95% confidence interval [CI], -1.2° to 6.4°) and paper PT +5° (95% CI, 0.99°-8.6°) were not inferior to outpatient PT based on a predefined 5° margin. Change in knee flexion from baseline was 0° for outpatient PT, -2° for web PT, and -1° for paper PT after 4 to 6 weeks and 8°, 8°, and 12° for the three groups, respectively, after 6 months. Additionally, there was no difference in the change in KOOS from baseline at 4 to 6 weeks or 6 months postoperatively as well as time back to work, driving, and walking without an assistive device. CONCLUSIONS: Unsupervised home exercise is an effective rehabilitation strategy after primary TKA and was noninferior to formal outpatient PT in selected patients. It is worthwhile to reconsider the current practice of automatically designating patients for outpatient PT after primary TKA, because appropriately selected patients with adequate clinical support can achieve similar results at home. LEVEL OF EVIDENCE: Level I, therapeutic study.

Does an Elastic Compression Bandage Provide Any Benefit After Primary TKA?

BACKGROUND: Compression bandages often are used after TKA to reduce swelling. However, the degree to which they are helpful has not been well characterized. QUESTIONS/PURPOSES: The purpose of this study was to determine whether use of a compression bandage after TKA was associated with (1) less leg swelling (our primary endpoint); or (2) secondary study endpoints, including improved ROM of flexion and extension, lower visual analog scale (VAS) pain scores for worst pain and pain during physical therapy just before surgery, postoperative day (POD) 1, POD 2, and POD 28, or fewer wound complications within 90 days of surgery. METHODS: A prospective, single-center, two-arm, parallel-group randomized controlled trial was conducted on 51 patients undergoing simultaneous, bilateral, primary TKA between February 2015 and August 2016. Patients were excluded if they had a body mass index > 40 kg/m, a history of a venous thromboembolic event, an allergy to the dressing or compression bandage, or lymphedema in one or both legs. Participants averaged a mean age of 62 years (range, 40-83 years). In all patients, we released the tourniquet after full wound closure, and we applied an Aquacel dressing to both limbs. Patients were randomized by opaque envelope, and the compression bandage was applied to the randomized limb. For each leg, study personnel not involved in patient care measured the patients' limb circumference (thigh, knee, and tibia), ROM, and VAS pain scores 24 hours after surgery, 48 hours after surgery, and on POD 28. The minimal clinically important difference for circumference was 2 cm with a SD of 2 cm in the circumference. For VAS, it was 2 points with a SD of 2. For ROM, it was 10° with a SD of 15. We conservatively picked an effect size of 0.5 SD and assumed a correlation between limbs of 0.3. This set the power level at 0.80 with an α error of 0.05; thus, a power analysis for paired t-tests indicated that 45 patients would be an appropriate sample size. There were 29 patients randomized to the right leg group and 22 patients randomized to the left leg group. There were no differences between the limb with and without the compression bandage preoperatively. RESULTS: Postoperatively, there were no differences between the groups in terms of leg swelling at the thigh (POD 1: mean ± SD = 51 ± 6 with compression bandage versus mean ± SD = 51 ± 6 without compression bandage, mean Δ = - 0.14, 95% confidence interval [CI], -0.65 to 0.37], p = 0.586; POD 2: mean ± SD = 53 ± 6 with compression bandage versus mean ± SD = 53 ± 7 without compression bandage, mean Δ = -0.22, 95% CI, -0.95 to 0.51, p = 0.548; POD 28: mean ± SD = 47 ± 6 with compression bandage versus mean ± SD = 47 ± 6 without compression bandage, mean Δ = -0.01, 95% CI, -0.39 to 0.38, p = 0.975), knee (POD 1: mean ± SD = 45 ± 4 with compression bandage versus mean ± SD = 45 ± 5 without compression bandage, mean Δ = -0.44, 95% CI, -1.16 to 0.28, p = 0.223; POD 2: mean ± SD = 46 ± 4 with compression bandage versus mean ± SD = 46 ± 4 without compression bandage, mean Δ = -0.30, 95% CI, -0.69 to 0.10, p = 0.137; POD 28: mean ± SD = 42 ± 5 with compression bandage versus mean ± SD = 42 ± 5 without compression bandage, mean Δ = 0.21, 95% CI, -0.34 to 0.76, p = 0.446), and shin (POD 1: mean ± SD = 40 ± 4 with compression bandage versus mean ± SD = 40 ± 4 without compression bandage, mean Δ = -0.22, 95% CI, -1.23 to 0.79, p = 0.659; POD 2: mean ± SD = 41 ± 4 with compression bandage versus mean ± SD = 41 ± 4 without compression bandage, mean Δ = -0.31, 95% CI, -0.72 to 0.09, p = 0.126; POD 28: mean ± SD = 37 ± 4 with compression bandage versus mean ± SD = 37 ± 4 without compression bandage, mean Δ = -0.34, 95% CI, -0.92 to 0.24, p = 0.246). There were no differences between the groups in terms of flexion ROM (POD 1: mean ± SD = 56 ± 25 with compression bandage versus mean ± SD = 58 ± 22 without compression bandage, mean Δ = -2.63, p = 0.234; POD 2: mean ± SD = 64 ± 20 with compression bandage versus mean ± SD = 63 ± 23 without compression bandage, mean Δ = 1.22, p = 0.534; POD 28: mean ± SD = 101 ± 20 with compression bandage versus mean ± SD = 102 ± 20 without compression bandage, mean Δ = -1.64, p = 0.103) and extension (POD 1: mean ± SD = 12 ± 7 with compression bandage versus mean ± SD = 12 ± 7 without compression bandage, mean Δ = 0.51, p = 0.328; POD 2: mean ± SD = 9 ± 5 with compression bandage versus mean ± SD = 10 ± 6 without compression bandage, mean Δ = -1.28, p = 0.061; POD 28: mean ± SD = 6 ± 14 with compression bandage versus mean ± SD = 4 ± 4 without compression bandage, mean Δ = 2.19, p = 0.252). With the numbers available, we observed greater maximal postoperative pain for the limb with the compression bandage than the control limb on POD 1 and POD 2, but not on POD 28 (POD 1: mean ± SD = 8 ± 3 with compression bandage versus mean ± SD = 7 ± 3 without compression bandage, mean Δ = 0.66, p = 0.030; POD 2: mean ± SD = 7 ± 2 with compression bandage versus mean ± SD = 7 ± 3 without compression bandage, mean Δ = 0.80, p = 0.008; POD 28: mean ± SD = 4 ± 3 with compression bandage versus mean ± SD = 3 ± 3 without compression bandage, mean Δ = 0.14, p = 0.526). Likewise, there was greater pain during physical therapy for the limb with the compression bandage than the limb without on POD 2, but not on POD 1 and POD 28 (POD 1: mean ± SD = 7 ± 3 with compression bandage versus mean ± SD = 6 ± 3 without compression bandage, mean Δ = 0.29, p = 0.460; POD 2: mean ± SD = 8 ± 2 with compression bandage versus mean ± SD = 7 ± 3 without compression bandage, mean Δ = 0.67, p = 0.018; POD 28: mean ± SD = 5 ± 2 with compression bandage versus mean ± SD = 5 ± 3 without compression bandage, mean Δ = 0.14, p = 0.600). With the numbers available, we observed no difference in 90-day wound healing complications between the limb with and the limb without the compression dressing; however, the sample size was too small to analyze this in a meaningful statistical way. Overall, there were 6% total wound complications in the compression bandage group and 12% total wound complications in the group without the compression bandage (odds ratio [OR], 0.47; p = 0.487). Drainage was not observed in the group with the compression bandage, whereas the group without the compression bandage had 6% drainage (OR, 0.00; p = 0.243). There were no deep infections or reoperations within 90 days postoperatively. CONCLUSIONS: Applying a compression bandage after TKA did not result in any clinical improvement in limb circumference, ROM, or pain. Based on this study, we believe that applying a compression bandage after TKA neither benefits nor harms the patient. Thus, we no longer use compression dressings for routine primary TKA. LEVEL OF EVIDENCE: Level I, therapeutic study.

Mechanical Complications Following Total Hip Arthroplasty Based on Surgical Approach: A Large, Single-Institution Cohort Study.

BACKGROUND: The influence of surgical approach on risk of early postoperative mechanical complications after total hip arthroplasty (THA) continues to be a focus of debate. We performed the first single-institution study on risk of early operative and nonoperative mechanical complications after THA based on approach, with the hypothesis that there would be no clinically significant difference with modern surgical methods. METHODS: A retrospective study was conducted on 16,186 consecutive THA performed from 2010 to 2016. Revision or conversion THA and cases performed for hip fracture, with recalled prostheses, or during a surgeon's learning period were excluded. THAs were performed using direct anterior (DA; n = 5465), direct lateral (DL; n = 8561), or posterolateral approach with soft tissue repair (PL; n = 2160). All mechanical complications within the first 2 years were identified. The primary analysis was a time to event Cox regression, accounting for both patient and surgeon characteristics. RESULTS: Compared with the DL approach, risk of mechanical complications was higher for both DA and PL. Adjusted risk of instability within 2 years was 0.17%, 0.74%, and 1.74% for DL, DA, and PL, respectively. While occurring at similar rates with the PL and DL approaches, the risk of periprosthetic fracture and loosening increased with DA. Consequently, femoral failure, including fracture or loosening, occurred more frequently for DA, with an adjusted incidence of 1.20% vs 0.58% and 0.47%, with DL and PL. CONCLUSION: Even with soft tissue repair, instability continues to occur with increased frequency with the PL approach. While reducing dislocation, a higher risk of femoral failure with DA must also be considered. Nevertheless, the DL approach appears to confer the lowest overall risk of mechanical complications.

Femoral Nerve Palsy Following Total Hip Arthroplasty: Incidence and Course of Recovery.

BACKGROUND: Femoral nerve palsy (FNP) is a relatively uncommon complication following total hip arthroplasty (THA). There is little recent literature regarding the incidence of FNP and the natural course of recovery. METHODS: Using our institutional database, we identified postoperative FNPs from 17,350 consecutive primary THAs performed from 2011 to 2016. Hip exposures were performed using a direct lateral (modified Hardinge), direct anterior (Smith-Peterson), anterolateral (Watson-Jones), or posterolateral (Southern or Moore) approach. Patients with FNP were contacted to provide a subjective assessment of convalescence and underwent objective muscle testing to determine the extent of motor recovery. RESULTS: The overall incidence of FNP was 0.21% after THA, with the incidence 14.8-fold higher in patients undergoing anterior hip surgery using either a direct anterior (0.40%) or anterolateral (0.64%) approach. Significant recovery from FNP did not commence for a majority of patients until greater than 6 months postoperatively. Motor weakness had resolved in 75% of patients at 33.3 months, with remaining patients suffering from mild residual weakness that typically did not necessitate an assistive walking device or a knee brace. Nearly all patients had improved sensory manifestations, but such symptoms had completely resolved in less than 20% of patients. CONCLUSION: FNP after hip surgery remains relatively uncommon, but may increase with a growing interest in anterior THA exposures. A near complete recovery with only mild motor deficits can be expected for a majority of patients in less than 2 years, although sensory symptoms may persist.

Reduced Incidence of Intraoperative Femur Fracture With a Second-Generation Tapered Wedge Stem.

BACKGROUND: Intraoperative fractures during total hip arthroplasty (THA) are more common when using cementless stems. The purpose of this study was to investigate the impact of a new shorter second-generation cementless, tapered wedge stem with improved proximal femoral fit in reducing the incidence of intraoperative fracture. METHODS: A retrospective study was conducted on primary THA cases performed at a single institution using a first-generation or second-generation cementless stem from 2006-2016. All intraoperative femur fractures were identified, as well as early 30-day postoperative periprosthetic femur fractures, which could represent nondisplaced intraoperative fractures that were initially missed. Risk for intraoperative femur fracture was analyzed using logistic regression, accounting for demographic covariates and surgeon. RESULTS: Of 6473 primary THA performed with a cementless, tapered wedge stem during the study period, 3126 used a first-generation stem and 3347 used a second-generation stem. The incidence of intraoperative fracture was 1.79% for first-generation stems and 0.24% for second-generation stems, representing a 7.5-fold reduction of risk for fracture. After accounting for covariates, the odds of intraoperative fracture were 0.33 using the second-generation stem relative to the first-generation stem (P = .01). However, there was no significant difference in the odds of early 30-day postoperative fractures using the second-generation stem (odds ratio 0.93, P = .56). CONCLUSION: A new second-generation cementless stem resulted in a 7.5-fold decrease in the incidence of intraoperative femur fracture compared with the preceding stem.

Bilateral Total Hip Arthroplasty: 1-Stage or 2-Stage? A Meta-Analysis.

BACKGROUND: Total hip arthroplasty (THA) is one of the most successful orthopedic surgeries performed in the last 50 years. However, controversies still exist between conducting 1- or 2-stage bilateral THA. METHODS: Using PubMed, Ovid, Embase, and Cochrane library databases, we searched for papers written between January 1995 and October 2015 that contained the following search terms: "one-stage or two-stage" or "simultaneous or staged," and "hip" and "arthroplasty or replacement." A meta-analysis was conducted with the collected pooled data about major and minor systemic complications, surgical complications, and other perioperative data associated with 1- and 2-stage bilateral THA. Statistical analysis was performed by the Mantel-Haenszel method, and the fixed effect model was used to analyze data. RESULTS: There were 13 studies with 17,762 patients who underwent 1-stage bilateral THA and 46,147 patients who underwent 2-stage bilateral THA. One-stage bilateral THA had a lower risk of major systemic complications, less deep venous thrombosis, and shorter operative time compared with 2-stage bilateral THA. There were no significant differences in death, pulmonary embolism, cardiovascular complication, infections, minor complications, and other surgical complications between procedures. CONCLUSION: One-stage bilateral THA was superior to 2-stage bilateral THA in terms of major systemic complication, deep venous thrombosis, and surgical time compared with 2-stage bilateral THA. However, this study does not encourage performing 1-stage over 2-stage bilateral THA. Higher evidence level studies are necessary for further analysis.

Periarticular Injection of Liposomal Bupivacaine Offers No Benefit Over Standard Bupivacaine in Total Knee Arthroplasty: A Prospective, Randomized, Controlled Trial.

BACKGROUND: Periarticular injection of liposomal bupivacaine has been adopted as part of multimodal pain management after total knee arthroplasty (TKA). METHODS: In this prospective, randomized clinical trial, we enrolled 162 patients undergoing primary TKA in a single institution between January 2014 and May 2015. Eighty-seven patients were randomized to liposomal bupivacaine (experimental group), and 75 patients were randomized to free bupivacaine (control group). All patients received spinal anesthesia and otherwise identical surgical approaches, pain management, and rehabilitation protocols. Outcomes evaluated include the patient-reported visual analog pain scores, narcotic consumption, and narcotic-related side effects (Brief Pain Inventory) within 96 hours after surgery as well as functional outcomes using the Knee Society Score and the Short-Form 12 measured preoperatively and at 4-6 weeks after surgery. RESULTS: There were no statistically significant differences between the groups in terms of postoperative daily pain scores, narcotic consumption (by-day and overall), or narcotic-related side effects. There were no statistically significant differences between the groups in terms of surgical (P = .76) and medical complications or length of hospital stay (P = .35). There were no statistically significant differences in satisfaction between the groups (P = .56) or between the groups in postoperative Knee Society Score (P = .53) and the Short-Form 12 at 4-6 weeks (P = .82, P = .66). CONCLUSION: As part of multimodal pain management protocol, periarticular injection of liposomal bupivacaine compared with bupivacaine HCl did not result in any clinically or statistically significant improvement of the measured outcomes following TKA.

Single vs Repeat Surgical Skin Preparations for Reducing Surgical Site Infection After Total Joint Arthroplasty: A Prospective, Randomized, Double-Blinded Study.

BACKGROUND: Preventing surgical site infection (SSI) after total joint arthroplasty (TJA) is a high priority and is partly linked to the efficacy of surgical site preparation solutions (SPSs) in reducing the number of pathogens on the skin before incision. The aim of this study is to investigate the effectiveness of SRS reapplication after draping to reduce the incidence of SSI after TJA. METHODS: Six hundred patients undergoing primary TJA between 2010 and 2011 at a single institution were recruited and randomly assigned to one of 2 groups. The patients in the intervention group (n = 300) received SPS that included alcohol and povidone-iodine before draping and an additional SPS by iodine povacrylex and isopropyl alcohol before application of the final adhesive drape, whereas the patients in the control group (n = 300) received a single SPS with alcohol and povidone-iodine before draping. Randomization was performed by an opaque envelope, and the rates of SSI and blistering were compared between groups. RESULTS: Five seventy-seven patients completed the study and were included in the final analysis. There was a significant reduction in the incidence of superficial SSI for the intervention group (1.8%, 5 of 283) compared to the control group (6.5%, 19 of 294, P = .02). There were 2 (0.7%, 2 of 294) deep incisional SSIs in the control group, and 2 (0.7%, 2 of 283) organ-space SSIs in the intervention group (P = 1.00). In addition, skin blistering was lower in the intervention group (3.5%, 10 of 283) vs the control group (6.5%, 19 of 294), but this difference also did not reach statistical significance (P = .13). CONCLUSION: Reapplication of an SPS after draping and before the application of iodophor-impregnated incisive draping resulted in a significant reduction in the rate of SSI in patients undergoing elective TJA.

Timing of Symptomatic Pulmonary Embolism with Warfarin Following Arthroplasty.

The purpose is to determine the incidence and timing of pulmonary embolism for patients receiving warfarin for thrombo-prophylaxis following total joint arthroplasty (TJA). Current guidelines for duration of prophylaxis are nonspecific. Chemical prophylaxis carries the risk of bleeding and associated periprosthetic joint infection. We retrospectively studied 26,415 primary and revision TJA cases performed at our institution between 2000 and 2010. The overall 90-day rate of symptomatic PE was 1.07%. Fatal PE rate was 0.02%. Out of 283 documented symptomatic PE cases, 81% occurred within three postoperative days, 89% within one postoperative week, and 94% within two postoperative weeks. The risk of symptomatic PE appears to be highest during the first week after TJA. Efforts must be made to minimize risk during this period.

Aspirin: an alternative for pulmonary embolism prophylaxis after arthroplasty?

BACKGROUND: The most effective agent for prophylaxis against venous thromboembolic disease after total joint arthroplasty (TJA) remains unknown. The paucity of literature comparing different methods of pulmonary embolism (PE) prophylaxis and fear of litigation make it difficult for surgeons to abandon the use of aggressive chemical prophylaxis. QUESTIONS/PURPOSES: We compared the (1) overall frequency of symptomatic PE, (2) risk of symptomatic PE after propensity matching that adjusted for potentially confounding variables, and (3) other complications and length of stay before and after propensity matching in patients undergoing TJA at our institution who received either aspirin or warfarin prophylaxis. METHODS: A total of 28,923 patients underwent TJA between January 2000 and June 2012 at our institution, had either aspirin (325 mg twice daily; 2800 patients) or warfarin prophylaxis (26,123 patients), and were registered in our institutional electronic database. The incidence of symptomatic PE, symptomatic deep vein thrombosis (DVT), hematoma formation, infection, wound complications, and mortality up to 90 days postoperatively was collected from the database. We performed multivariate analysis and 3:1 and 5:1 propensity score matching for comorbid and demographic variables. RESULTS: The overall symptomatic PE rate was lower (p < 0.001) in patients receiving aspirin (0.14%) than in the patients receiving warfarin (1.07%). This difference did not change after matching. The aspirin group also had significantly fewer symptomatic DVTs and wound-related problems and shorter hospital stays, which did not change after matching. CONCLUSIONS: After publication of the American Academy of Orthopaedic Surgeons' guidelines, some surgeons have utilized aspirin as thromboprophylaxis after TJA. Based on our findings from a large institutional database, aspirin offers suitable prophylaxis against symptomatic PE in selected patients.

Symptomatic pulmonary embolus after joint arthroplasty: stratification of risk factors.

BACKGROUND: Prophylaxis for pulmonary embolism (PE) after total joint arthroplasty (TJA) presents the clinical dilemma of balancing the risk of postoperative thrombotic risk and anticoagulation-related complications such as bleeding, hematoma formation, and infection. Risk stratification of patients undergoing TJA is needed to tailor prophylaxis based on thrombotic and bleeding risk. QUESTIONS/PURPOSES: The purpose of this study was to identify the preoperative comorbidities that were associated with an increased risk of symptomatic PE after joint arthroplasty in a large group of patients who had TJAs and who were treated with either aspirin or warfarin. METHODS: We conducted a retrospective study of 26,391 primary and revision TJAs performed at our institution between January 2000 and April 2011. A total of 24,567 patients received warfarin prophylaxis for 6 weeks (targeted international normalized ratio of 1.5-2.0) and 1824 patients received 325 mg aspirin twice daily. Symptomatic patients with decreased oxygen saturation were evaluated for PE using either a ventilation/perfusion scan or multidetector CT scan. Symptomatic PEs occurring in patients within 90 days postoperatively identified with CT or ventilation/perfusion scans were considered complications related to surgery, and fatal PEs were those that occurred in patients who died during the hospital admission owing to cardiopulmonary failure after PE. Using a logistic regression analysis, a nomogram was created to predict postoperative symptomatic PE risk. RESULTS: Risk of postoperative symptomatic PE after primary and revision TJAs was 1.1%. Risk of postoperative fatal PE was 0.02%. Elevated BMI (p < 0.035), procedures on the knee (p < 0.006), higher Charlson Comorbidity Index (p < 0.015), chronic obstructive pulmonary disorder (p = 0.006), atrial fibrillation (p < 0.001), anemia (p < 0.001), presence of deep vein thrombosis (p < 0.001), and depression (p = 0.012) were independent risk factors for symptomatic PE. Based on these risk factors and derived scoring criteria, patients can be classified into low- (0.35%), medium- (1.4%), and high- (9.3%) risk categories. CONCLUSIONS: Patients who are obese, undergo knee procedures, have an elevated Charlson Comorbidity Index, chronic obstructive pulmonary disease, atrial fibrillation, anemia, depression, or postoperative deep vein thrombosis are at greater risk of having a postoperative PE develop. These risk factors should be considered when deciding on postoperative anticoagulation prophylaxis. LEVEL OF EVIDENCE: Level IV, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Proximal deep venous thrombosis and pulmonary embolus following total joint arthroplasty.

It has been proposed that prevention of deep venous thrombosis (DVT) will lead to a reduction in pulmonary embolism (PE). This retrospective comparative study examines the association between symptomatic proximal DVT (occurring at or proximal to the popliteal fossa) and PE in total joint arthroplasty (TJA) patients. We evaluated 1031 patients with DVT symptoms and 428 with PE symptoms. A total of 227 patients were evaluated for both. No statistically significant association found between developing PE and DVT within 90 days after TJA (P=0.94). Our findings raise into question the mechanical propagation theory. Formation of DVT and PE may be independent events in patients undergoing TJA. Evaluating the efficacy of thromboprophylaxis using DVT as end point may not reflect its efficacy for prevention of PE.

Surgical care improvement project (SCIP): has its mission succeeded?

The purpose of this study was to determine if adherence to the surgical care improvement project (SCIP) measures could further reduce rate of surgical site infection (SSI) and venous thromboembolism (VTE) in total joint arthroplasty (TJA) patients. We retrospectively identified all patients who underwent primary or revision TJA at our institution between July 2000 and June 2009. After implementation of SCIP measures, rate of superficial SSI increased (0.42% versus 0.60%, P=0.05) while rate of deep SSI decreased from 0.92% to 0.82% (P=0.46). The rate of DVT was 0.92% before and 0.83% after implementation of SCIP (P=0.51); however, rate of PE increased from 0.87% to 1.30% (P=0.002). Our findings indicated that SCIP has not been successful in reducing complications in TJA patients.

Does international normalized ratio level predict pulmonary embolism?

BACKGROUND: Preventing pulmonary embolism is a priority after major musculoskeletal surgery. The literature contains discrepant data regarding the influence of anticoagulation on the incidence of pulmonary embolism after joint arthroplasty. The American College of Chest Physicians guidelines recommend administration of oral anticoagulants (warfarin), aiming for an international normalized ratio (INR) level between 2 and 3. However, recent studies show aggressive anticoagulation (INR > 2) can lead to hematoma formation and increased risk of subsequent infection. QUESTIONS/PURPOSES: We asked whether an INR greater than 2 protects against pulmonary embolism. PATIENTS AND METHODS: We identified 9112 patients with 10,122 admissions for joint arthroplasty between 2004 and 2008. All patients received warfarin for prophylaxis, aiming for an INR level of 2 or lower. We assessed 609 of 10,122 admissions (6%) for pulmonary embolism using CT, ventilation/perfusion scan, or pulmonary angiography, and 163 of 10,122 admissions (1.6%) had a proven pulmonary embolism. RESULTS: Fifteen of 163 admissions (9%) had an INR greater than 2 before or on the day of workup compared to 35 of 446 admissions (8%) who were negative. We observed no difference between the INR values in patients with or without pulmonary embolism. CONCLUSIONS: We found no clinically relevant difference in the INR values of patients who did or did not develop pulmonary embolism. The risk of bleeding should be weighed against the risk of pulmonary embolism when determining an appropriate target INR for each patient, as an INR less than 2 may reduce the risk of bleeding while still protecting against pulmonary embolism. LEVEL OF EVIDENCE: Level III, therapeutic study. See Instructions to Authors for a complete description of levels of evidence.

Overdiagnosis of pulmonary embolism: evaluation of a hypoxia algorithm designed to avoid this catastrophic problem.

BACKGROUND: We observed a substantial increase in the incidence of pulmonary embolism (PE) after total joint arthroplasty (TJA) when multidetector computerized tomography (MDCT) replaced ventilation-perfusion (V/Q) scans as the diagnostic modality of choice. We questioned whether this resulted from the detection of clinically unimportant PE with the more sensitive MDCT and in 2007 instituted a hypoxia protocol to enhance the detection of PE. QUESTIONS/PURPOSES: We determined whether this new hypoxia protocol increased the specificity of our workups for suspected clinically important PE in the immediate postoperative period without affecting patient morbidity and mortality. PATIENTS AND METHODS: We compared the frequency of MDCT, V/Q scan and total investigations, incidence of PE, and overall mortality rates in the 3 years prior (January 2003 to December 2006) and 2 years after (January 2007 to November 2009) the implementation of the algorithm. RESULTS: After instituting the protocol, we observed a trend toward a decrease in the number of patients worked up for PE (4.6 to 4.0 per 100 TJAs, 13.5% decrease). At the same time, there was an increase in the percent of positive findings of PE per workup for PE (23-33 positive PEs per 100 patients, 40.5% increase). All-cause mortality rates decreased for the 30-day period (3.1 to 1.4 per 1000 TJAs, 53.5% decrease) and the 90-day period (5.0 to 2.6 per 1000 TJAs, 48.3% decrease). CONCLUSIONS: With the implementation of this algorithm, the specificity of our management of postoperative hypoxia and suspected clinically important PE improved without affecting patient morbidity or mortality.

Secondary resurfacing of the patella after primary total knee arthroplasty does the anterior knee pain resolve?

Although it has been shown that the risk of anterior knee pain is greater in patients with nonresurfaced patellae, it is not exactly clear whether the pain would resolve with secondary resurfacing of the patella. Thirty-nine patients (41 knees) underwent secondary patellar resurfacing between January 2001 and January 2007. The mean age was 66 years. The mean body mass index was 29.2 kg/m(2). The average time from primary total knee arthroplasty to resurfacing procedure was 29 months. The mean follow-up was 54 months. Anterior knee pain was the indication for secondary resurfacing in all patients. Although the clinical and functional knee scores improved significantly for whole cohort, 8 patients (8 knees) were dissatisfied with the outcome of surgery. This study highlights that secondary resurfacing is not an always rewarding procedure and patients need to be consulted appropriately with regard to the outcome.

A squeaky reputation: the problem may be design-dependent.

BACKGROUND: Squeaking is reportedly a complication in patients having ceramic-on-ceramic total hip implants. The etiology remains unknown and multifactorial with recent studies suggesting a relationship between the audible squeak and implant design. When we evaluated our ceramic-on-ceramic cohort, we noticed squeaking primarily in patients receiving an acetabular system designed with an elevated titanium rim. OBJECTIVES/PURPOSES: We therefore (1) determined the incidence of squeaking among four different ceramic-on-ceramic bearing surfaces used for THA at our institution; (2) evaluated the association between different acetabular designs and the incidence of squeaking; and (3) assessed other potential variables associated with squeaking. METHODS: We retrospectively reviewed 1507 patients having a ceramic-on-ceramic THA between 2002 and 2009; we separately analyzed those receiving an acetabular system with and without an elevated titanium rim. Data were collected through phone-administered questionnaires and retrospective reviews of patient charts for intraoperative findings, followup reports, demographic information, and radiographic findings. RESULTS: Squeaking occurred in 92 of the 1507 patients (6%). All 92 patients with squeaking received an elevated rim design (1291 patients) or an incidence of 7% with that design. We found no association between squeaking and any other examined factors. CONCLUSION: Our findings complement the theory from in vitro studies suggesting that neck impingement on the elevated titanium rim is the probable cause of the increased frequency of squeaking with this design.

Hip dislocation: are hip precautions necessary in anterior approaches?

BACKGROUND: In 2005, we reported removal of functional restriction after primary THA performed through the anterolateral approach did not increase the incidence of dislocation. QUESTIONS/PURPOSES: To develop a current practice guideline, we evaluated the incidence of early dislocation after primary THA after implementation of a no-restriction protocol. METHODS: Between January 2005 and December 2007, 2532 patients (2764 hips; 1541 women, 1223 men; mean age, 63.2 years [28-98 years]) underwent primary THA at our institution. Bilateral THA was performed in 232 patients (464 hips). The direct anterior or anterolateral approach was used in all patients. Femoral head size was 28, 32, or 36 mm. Patients were given no traditional functional restrictions postoperatively, such as use of elevated seats, abduction pillows, and restriction from driving. All patients received standard care at the judgment of the attending surgeon. One hundred forty-six patients missed followup appointments despite efforts to be contacted by telephone. The remaining 2386 of 2532 patients (94%) had a minimum followup of 6 months (mean, 14.2 months; range, 6-34 months). RESULTS: Four known dislocations occurred in the followed cohort of 2386 patients with 2612 hips (0.15%) at a mean of 5 days (3-12 days) postoperatively, none related to high-impact trauma. One dislocation occurred in a patient with a history of developmental dysplasia of the hip, two dislocations occurred while at the toilet (one with a previous hip fracture treated with a modular system), and one dislocation was idiopathic. CONCLUSIONS: We confirmed a low incidence of dislocation after primary THA in the absence of early postoperative restrictions. We conclude a no-restriction protocol does not increase the incidence of early dislocation after primary THA. LEVEL OF EVIDENCE: Level II, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.