Background: Lymphedema is a chronic disease characterized by fluid buildup and swelling that can lead to skin and soft-tissue fibrosis and recurring soft-tissue infections. Literature with regard to the increased risk of complications following a surgical procedure in patients with lymphedema is emerging, but the impact of lymphedema in the setting of primary total hip arthroplasty (THA) remains unknown. The purpose of this study was to review outcomes following primary THA performed in patients with lymphedema compared with a matched cohort without lymphedema. Methods: Using our institutional total joint registry and medical records, we identified 83 patients (57 were female and 26 were male) who underwent THA with ipsilateral lymphedema. For comparison, these patients were matched 1:6 (based on sex, age, date of the surgical procedure, and body mass index [BMI]) to a group of 498 patients without lymphedema who underwent primary THA for osteoarthritis. Subsequently, postoperative complications and implant survivorship were evaluated for each group. The mean follow-up for each group was 6 years. Survivorship was compared between cohorts using Kaplan-Meier methodology and included both survivorship free of infection and survivorship free of reoperation or revision. Univariate Cox regression analysis was utilized to assess the association between patient factors for the time to event outcomes noted above. Results: In patients with a history of lymphedema, there was an increased risk of complications (hazard ratio [HR], 1.97; p < 0.01), including reoperation for any cause (HR, 3.16; p < 0.01) and postoperative infection (HR, 4.48; p < 0.01). The 5-year infection-free survival rate was 90.3% for patients with lymphedema compared with 97.7% for patients without lymphedema (p < 0.01). Conclusions: Patients with lymphedema are at increased risk for complications, including reoperation and infection, following primary THA. These data emphasize the importance of appropriate preoperative counseling in this population and should encourage efforts to identify methods to improve outcomes, including further investigation of the effects of preoperative optimization of lymphedema prior to THA and methods for improved perioperative management. Level of Evidence: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.
Prevalence of groin pain after primary dual-mobility total hip arthroplasty
Background: Instability remains a challenging problem following total hip arthroplasty (THA). Dual-mobility (DM) components are used with increasing frequency to mitigate this potential complication. As has been shown with larger metal-on-metal (MoM) THA, the larger size femoral head may pose an increased risk of groin pain. This study aims to evaluate the prevalence of groin pain following primary DM THA compared to other THA constructs. Methods: We identified 190 primary THAs (183 patients) performed with DM components at a single academic institution from 2008 to 2017. We retrospectively reviewed standardised patient questionnaires and the electronic medical record to determine the prevalence of groin pain. DM patients were compared to historical controls of 39 MoM hip resurfacing, 26 large-head MoM THA, and 217 conventional THA. Mean age was 64 years, 58% were female, mean body mass index was 30 kg/m 2 , and mean follow-up was 3.5 years (range 2–8 years). Results: The prevalence of groin pain in patients with DM components was 5%, similar to the prevalence reported by patients with conventional THA (7%). There was a decreased prevalence of groin pain in DM patients compared to hip resurfacing (18%) and MoM THA (15%). Among the 9 DM patients with groin pain, 1 was treated with iliopsoas injection, and 1 underwent radiofrequency ablation of the articular nerve. Conclusions: This study documents a relatively low prevalence of groin pain among primary DM THA patients. This is comparable with historical controls of conventional THA and decreased compared to hip resurfacing and large head MoM THA.
Outcomes of Primary Total Knee Arthroplasty Following Septic Arthritis of the Native Knee
Background: Septic arthritis of the native knee often results in irreversible joint damage leading to the need for total knee arthroplasty (TKA). The purpose of the present study was to examine the intermediate-term risk of periprosthetic joint infection (PJI), aseptic revision, and reoperation following primary TKA in patients with a history of septic arthritis of the native knee as compared with primary TKA performed for the treatment of osteoarthritis. Methods: We retrospectively identified 215 primary TKAs performed from 1971 to 2016 at a single institution in patients with a history of septic arthritis of the native knee. Each case was matched 1:1 based on age, sex, body mass index (BMI), and surgical year to a TKA for osteoarthritis. The mean age and BMI were 63 years and 30 kg/m 2 , respectively. The mean duration of follow-up was 9 years. Results: Survivorships free of PJI at 10 years were 90% and 99% for the septic arthritis and osteoarthritis groups, respectively (hazard ratio [HR] = 6.1; p < 0.01). Ten-year survivorships free of any aseptic revisions were 83% and 93% (HR = 2.5; p < 0.01), and survivorships free of any reoperation were 61% and 84% (HR = 2.9; p < 0.01) for the septic arthritis and osteoarthritis groups, respectively. In addition, as time from the diagnosis of native knee septic arthritis to TKA increased, the relative risk of subsequent infection decreased. Preoperative and 2-year postoperative Knee Society scores were similar between the groups (p = 0.16 and p = 0.19, respectively). Conclusions: There was a 6.1-fold increased risk of PJI in patients undergoing TKA with a history of native knee septic arthritis when compared with controls undergoing TKA for the treatment of osteoarthritis, with a cumulative incidence of 9% at 10 years. Subgroup analysis of the septic arthritis cohort revealed a higher risk of any infection in patients who underwent TKA within the first 5 to 7 years after the diagnosis of septic arthritis as compared with those with a greater duration. Moreover, the 10-year rates of survival free of aseptic revision, any revision, and any reoperation were significantly worse in the native knee septic arthritis cohort. Level of Evidence: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.
Extended Trochanteric Osteotomy in Revision Total Hip Arthroplasty
Background: Extended trochanteric osteotomies (ETOs) provide wide femoral and acetabular exposure, give direct access to the femoral medullary canal, and facilitate implant removal and new implant placement during selected revision total hip arthroplasties (THAs). Previous studies are limited by modest patient numbers and limited length of follow-up. The goals of the current study were to assess the union rate, complications, and outcomes of contemporary ETOs performed during revision THAs. Methods: From 2003 to 2013, 612 ETOs were performed during revision THAs at 1 institution using 2 techniques: Paprosky (laterally based osteotomy; n = 367) and Wagner (anteriorly based osteotomy; n = 245). The indications for the revision procedures were aseptic loosening (65%), periprosthetic joint infection (18%), periprosthetic fracture (6%), femoral implant fracture (5%), and other (6%). The mean patient age was 69 years, and 57% of the patients were male. The mean number of previous THAs was 1.6. The median duration of follow-up was 5 years (range, 2 to 13 years). Results: The mean Harris hip scores increased from 57 preoperatively to 77 at the latest follow-up (p < 0.001). Radiographic and clinical union was achieved in 98% of the patients at a mean of 6 months (range, 1 to 24 months). The mean migration of the proximal trochanteric osteotomy fragment prior to union was 3 mm (range, 0 to 29 mm). ETO fragment migration of >1 cm occurred in 7% (37) of the 501 hips that had radiographic analysis. Nine hips (2%) had nonunion of the ETO. Intraoperative fracture of the ETO diaphyseal fragment occurred in 22 hips (4%), postoperative fracture of the ETO diaphyseal fragment occurred in 3 hips (0.5%), and postoperative fracture of the greater trochanter occurred in 41 hips (7%). Survivorship at 10 years free of revision for aseptic femoral loosening, free of femoral or acetabular component removal or revision for any reason, and free of reoperation for any reason was 97%, 91%, and 82%, respectively. Conclusions: This large series of ETOs shows that the union rate is high and clinically important trochanteric migration is infrequent. The most common complications are fracture of the osteotomy fragment intraoperatively or postoperatively. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.
Hitting the Target: Natural History of the Hip Based on Achieving an Acetabular Safe Zone Following Periacetabular Osteotomy
Background: Periacetabular osteotomy (PAO) remains the gold-standard treatment for acetabular dysplasia in skeletally mature patients with preserved cartilage. The purpose of this multicenter cohort study was to delineate the long-term radiographic natural history of the dysplastic hip following PAO based on the final position of the acetabular fragment. Methods: We evaluated patients who underwent PAO performed by 4 hip preservation surgeons to treat acetabular dysplasia with or without concomitant retroversion from 1996 to 2012 at 3 academic institutions. There were 288 patients with a mean clinical and radiographic follow-up of 9 years (range, 5 to 21 years). Postoperative radiographs made at the first clinical visit were used to determine if the acetabular fragment fell into a safe zone according to the absence of retroversion, a lateral center-edge angle (LCEA) of 25° to 40°, an anterior center-edge angle (ACEA) of 25° to 40°, and a Tönnis angle of 0° to 10°. Every available subsequent radiograph was assessed for degenerative changes by the Tönnis classification (grades 0 to 3). The time to progression was analyzed using Cox proportional hazards regression and multistate modeling. Results: Only the absence of retroversion was independently associated with a decreased risk of progressing at least 1 Tönnis grade during follow-up: hazard ratio (HR), 0.60 (95% confidence interval [CI], 0.38 to 0.94; p = 0.025). Achieving the ACEA safe zone yielded the greatest time increase for remaining in Tönnis grade 0 or 1 (43 years for having an ACEA in the safe zone compared with 28 years for not having an ACEA in the safe zone), followed by the absence of retroversion (34 years for the absence of retroversion compared with 24 years for the presence of retroversion). However, attaining the Tönnis angle or LCEA safe zones did not delay progression. The achievement of additional safe zones generally increased the length of time that patients spent in Tönnis grade 0 or 1: 25 years for 0 safe zones, 36 years for 1 safe zone, 29 years for 2 safe zones, 37 years for 3 safe zones, and 44 years for 4 safe zones. Conclusions: This study demonstrates the importance of achieving appropriate acetabular reorientation to enhance the longevity of the native hip following PAO. Although the LCEA and the Tönnis angle are the most common metrics used to assess appropriate acetabular correction, this study shows that adequately addressing retroversion and the ACEA has a greater impact on improving the natural history. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.
More Predictable Return of Motor Function with Mepivacaine Versus Bupivacaine Spinal Anesthetic in Total Hip and Total Knee Arthroplasty
Background: Spinal anesthesia provides several benefits for patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA), but historically comes at the cost of slow and unpredictable return of lower-extremity motor function related to the use of long-acting local anesthetics. In this prospective, double-blinded, randomized clinical trial we sought to determine if an alternative local anesthetic, mepivacaine, would allow more consistent return of motor function compared with low-dose bupivacaine spinal anesthesia during primary THA and TKA. Methods: This trial was conducted at a single academic institution. Prior to trial initiation an internal pilot study determined that 154 patients were required to achieve 80% power. Patients were randomized in a 1:1 fashion with use of advanced computerized stratification based on procedure, age group, sex, and body mass index. Following the surgical procedure, motor function was assessed every 15 minutes in the nonoperative lower extremity according to the Bromage scale and discontinued once Bromage 0 was achieved (spontaneous movement at hip, knee, and ankle). Results: Return of lower-extremity function was more predictable in patients who received mepivacaine than in those who received low-dose bupivacaine. Among patients who received mepivacaine, 1% achieved motor function return beyond 5 hours compared with 11% of patients who received bupivacaine (p = 0.013). The mean time to return of lower-extremity motor function was 26 minutes quicker in patients who received mepivacaine (185 minutes; 95% confidence interval, 174 to 196 minutes) compared with low-dose bupivacaine (210 minutes; 95% confidence interval, 193 to 228 minutes) (p = 0.016). There were no significant differences in safety outcomes including pain scores, time to participation in physical therapy, incidence of orthostatic hypotension, urinary retention, or transient neurologic symptoms in patients receiving mepivacaine compared with low-dose bupivacaine. Conclusions: In patients undergoing primary THA and TKA, spinal anesthesia with mepivacaine allowed more consistent return of lower-extremity motor function compared with low-dose bupivacaine, without a concomitant increase in complications potentially associated with spinal anesthetics. This is particularly of value in an era of short-stay and outpatient surgical procedures. Level of Evidence: Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.
Implementation of Procedure-Specific Opioid Guidelines
Background: Evidence-based, procedure-specific guidelines for prescribing opioids are urgently needed to optimize pain relief while minimizing excessive opioid prescribing and potential opioid diversion in our communities. A multidisciplinary panel at our institution recently developed procedure-specific guidelines for discharge opioid prescriptions for common orthopaedic surgical procedures. The purpose of this study was to evaluate postoperative opioid prescription quantities, variability, and 30-day refill rates before and after implementation of the guidelines. Methods: This retrospective cohort study was conducted at a single academic institution from December 2016 to March 2018. Guidelines were implemented on August 1, 2017, with a recommended maximum opioid prescription quantity for 14 common orthopaedic procedures. Patients who underwent these 14 procedures during the period of December 2016 to May 2017 made up the pre-guideline cohort (n = 2,223), and patients who underwent these procedures from October 2017 to March 2018 made up the post-guideline cohort (n = 2,300). Opioid prescription quantities were reported as oral morphine equivalents (OME), with medians and interquartile ranges (IQRs). Four levels were established for recommended prescription maximums, ranging from 100 to 400 OME. Results: In the pre-guideline cohort, the median amount of prescribed opioids across all procedures was 600 OME (IQR, 390 to 863 OME), which decreased by 38% in the post-guideline period, to a median of 375 OME (IQR, 239 to 400 OME) in the post-guideline cohort (p < 0.001). The 30-day refill rate did not change significantly, from a rate of 24% in the pre-guideline cohort to 25% in the post-guideline cohort (p = 0.43). Multivariable analysis demonstrated that guideline implementation was the factor most strongly associated with prescriptions exceeding guideline maximums (odds ratio [OR] = 9.9; p < 0.001). Age groups of <80 years (OR = 2.0 to 2.4; p < 0.001) and males (OR = 1.2; p = 0.025) were also shown to have higher odds of exceeding guideline maximums. Conclusions: Procedure-specific guidelines are capable of substantially decreasing opioid prescription amounts and variability. Furthermore, the absence of change in refill rates suggests that pain control remains similar to pre-guideline prescribing practices. Evidence-based guidelines are a readily employable solution that can drive rapid change in practice and enhance the ability of orthopaedic surgeons to provide responsible pain management.
Long-Term Results of Total Knee Arthroplasty with Contemporary Distal Femoral Replacement
Background: Distal femoral replacement (DFR) is a salvage option for complex primary and revision total knee arthroplasty (TKA). Although excellent immediate fixation and weight-bearing are achieved, there is a paucity of data on long-term outcomes of TKA with DFR. The purpose of the present study was to determine implant survivorship, clinical outcomes, and radiographic results of TKAs with contemporary DFR components in a large series. Methods: We identified 144 consecutive TKAs performed with DFR for non-oncologic indications from 2000 to 2015 at a single academic institution. Indications for the index DFR included 66 (46%) for native (n = 11) or periprosthetic (n = 55) femoral fracture, 40 (28%) for staged treatment of periprosthetic joint infection, 28 (19%) for aseptic TKA loosening, and 10 (7%) for other indications. Porous metal cones were used to augment femoral fixation in 28 patients (19%) and tibial fixation in 38 patients (26%). Outcomes included cumulative incidence of revision and reoperation (utilizing a competing risk model), Knee Society scores, and radiographic results. The mean age at the time of index DFR was 72 years, and 65% of patients were female. The mean follow-up was 5 years (range, 2 to 13 years) for the 111 patients who did not undergo revision, had not died, and were not lost to follow-up. Results: The 10-year cumulative incidences of revision for aseptic loosening, all-cause revision, and any reoperation were 17.0%, 27.5%, and 46.3%, respectively. There was an increased risk of reoperation in patients who underwent index DFR for aseptic TKA loosening (hazard ratio [HR], 2.30; p = 0.026) or periprosthetic joint infection (HR, 2.18; p = 0.022) compared with periprosthetic or native femoral fractures. However, there was no difference in risk of revision for aseptic loosening or all-cause revision based on the original operative indication. The mean Knee Society score increased from 45 preoperatively to 71 at the time of the latest follow-up (p < 0.001). Radiographic loosening was observed in 8 unrevised DFRs (7%). There were 7 above-the-knee amputations performed at the time of the final follow-up, all for intractable periprosthetic joint infection. Conclusions: TKAs with contemporary DFR had high 10-year cumulative incidences of both revision and reoperation, underscoring the salvage nature of this procedure as a final reconstructive option. Most patients experienced substantial clinical improvements with this end-stage revision procedure. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.
Use of Natural Language Processing Algorithms to Identify Common Data Elements in Operative Notes for Total Hip Arthroplasty
Update This article was updated on December 6, 2019, because of a previous error. On page 1936, in Table VII, “Performance of the Bearing Surface Algorithm,” the row that had read “Bearing surface predicted by algorithm” now reads “Bearing surface predicted by algorithm*.” An erratum has been published: J Bone Joint Surg Am. 2020 Jan 2;102(1):e4. Update This article was updated on March 31, 2020, because of a previous error. On page 1934, in Table IV (“THA Bearing Surface-Related Keywords in Operative Notes”), the row that had read “Femoral stem; stem; HFx-stem; femoral component; femoral component/stem; permanent prosthesis; stem fem cemented” now reads “Femoral head; ball; delta head; delta ceramic head; ion treated; BIOLOX delta; ceramic head; ceramic femoral head; ceramic offset head; ceramic (size) head; alumina ceramic head; alumina prosthetic head; alumna ceramic head; BIOLOX ceramic head; BIOLOX delta head; BIOLOX femoral head; BIOLOX delta ceramic head.” An erratum has been published: J Bone Joint Surg Am. 2020 May 6;102(9):e43. Background: Manual chart review is labor-intensive and requires specialized knowledge possessed by highly trained medical professionals. Natural language processing (NLP) tools are distinctive in their ability to extract critical information from raw text in electronic health records (EHRs). As a proof of concept for the potential application of this technology, we examined the ability of NLP to correctly identify common elements described by surgeons in operative notes for total hip arthroplasty (THA). Methods: We evaluated primary THAs that had been performed at a single academic institution from 2000 to 2015. A training sample of operative reports was randomly selected to develop prototype NLP algorithms, and additional operative reports were randomly selected as the test sample. Three separate algorithms were created with rules aimed at capturing (1) the operative approach, (2) the fixation method, and (3) the bearing surface category. The algorithms were applied to operative notes to evaluate the language used by 29 different surgeons at our center and were applied to EHR data from outside facilities to determine external validity. Accuracy statistics were calculated with use of manual chart review as the gold standard. Results: The operative approach algorithm demonstrated an accuracy of 99.2% (95% confidence interval [CI], 97.1% to 99.9%). The fixation technique algorithm demonstrated an accuracy of 90.7% (95% CI, 86.8% to 93.8%). The bearing surface algorithm demonstrated an accuracy of 95.8% (95% CI, 92.7% to 97.8%). Additionally, the NLP algorithms applied to operative reports from other institutions yielded comparable performance, demonstrating external validity. Conclusions: NLP-enabled algorithms are a promising alternative to the current gold standard of manual chart review for identifying common data elements from orthopaedic operative notes. The present study provides a proof of concept for use of NLP techniques in clinical research studies and registry-development endeavors to reliably extract data of interest in an expeditious and cost-effective manner.
Natural History of the Dysplastic Hip Following Modern Periacetabular Osteotomy
Background: Periacetabular osteotomy (PAO) is the most common treatment for symptomatic acetabular dysplasia, or developmental dysplasia of the hip (DDH), in skeletally mature patients. The purpose of this multicenter cohort study was to delineate the long-term radiographic natural history of the dysplastic hip following PAO. Methods: We evaluated all patients undergoing PAO from 1996 to 2012 at 3 academic institutions in the United States. Inclusion criteria were PAO for DDH with a minimum 5-year radiographic follow-up. Exclusion criteria were PAO for isolated acetabular retroversion, neurogenic dysplasia, Legg-Calvé-Perthes disease, and prior hip surgery including osteotomies and arthroscopy. There were 288 patients, 83% of whom were women; the mean age and body mass index (BMI) were 29 years and 25 kg/m 2 , respectively. The mean clinical and radiographic follow-up was 9.2 years (range, 5.0 to 21.1 years). Every preoperative and postoperative hip radiograph was assessed to determine the degree of osteoarthritis according to the Tönnis classification. Survivorship was analyzed by multistate modeling, enabling assessment of progression through the Tönnis grades rather than just individual transitions as with Kaplan-Meier techniques. Results: At the time of final follow-up, 144 patients (50%) had progressed at least 1 Tönnis grade, with 42 patients (14.6%) undergoing total hip arthroplasty. The mean number of years spent in each Tönnis grade following PAO was 19 for Tönnis grade 1, 8 for Tönnis grade 2, and 4 for Tönnis grade 3. The probability of progression to total hip arthroplasty increased significantly on the basis of a higher initial Tönnis grade (p < 0.001). The most marked difference occurred between Tönnis grade 0 or 1 and Tönnis grade 2; for Tönnis grade 1, the probability of progression to total hip arthroplasty at 5 and 10 years was 2% and 11%, respectively, compared with 23% and 53%, respectively, for Tönnis grade 2. Conclusions: PAO effectively alters the natural history of DDH. Precise radiographic progression based on the Tönnis grade can now be used to ascribe prognosis for the native hip. Importantly, this investigation demonstrates a stark increase in progression to total hip arthroplasty within 10 years of PAO for patients with preoperative Tönnis grade-2 osteoarthritis compared with those with Tönnis grade-0 or 1 osteoarthritis. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.