The incidence of subsequent hip arthroscopy after rectus-sparing periacetabular osteotomy.

Aims: Periacetabular osteotomy (PAO) is the preferred treatment for symptomatic acetabular dysplasia in adolescents and young adults. There remains a lack of consensus regarding whether intra-articular procedures such as labral repair or improvement of femoral offset should be performed at the time of PAO or addressed subsequent to PAO if symptoms warrant. The purpose was to determine the rate of subsequent hip arthroscopy (HA) in a contemporary cohort of patients, who underwent PAO in isolation without any intra-articular procedures. Methods: From June 2012 to March 2022, 349 rectus-sparing PAOs were performed and followed for a minimum of one year (mean 6.2 years (1 to 11)). The mean age was 24 years (14 to 46) and 88.8% were female (n = 310). Patients were evaluated at final follow-up for patient-reported outcome measures (PROMs). Clinical records were reviewed for complications or subsequent surgery. Radiographs were reviewed for the following acetabular parameters: lateral centre-edge angle, anterior centre-edge angle, acetabular index, and the alpha-angle (AA). Patients were cross-referenced from the two largest hospital systems in our area to determine if subsequent HA was performed. Descriptive statistics were used to analyze risk factors for HA. Results: A total of 16 hips (15 patients; 4.6%) underwent subsequent HA with labral repair and femoral osteochondroplasty, the most common interventions. For those with a minimum of two years of follow-up, 5.3% (n = 14) underwent subsequent HA. No hips underwent total hip arthroplasty and one revision PAO was performed. Overall, 17 hips (4.9%) experienced a complication and 99 (26.9%) underwent hardware removal. All PROMs improved significantly postoperatively. Radiologically, 80% of hips (n = 279) reached the goal for acetabular correction (77% for acetbular index and 93% for LCEA), with no significant differences between those who underwent subsequent HA and those who did not. Conclusion: Rectus-sparing PAO is associated with a low rate of subsequent HA for intra-articular pathology at a mean of 6.2 years' follow-up (1 to 11). Acetabular correction alone may be sufficient as the primary intervention for the majority of patients with symptomatic acetabular dysplasia.

Dysplastic Hips That Are Too Late For Periacetabular Osteotomy Are Not Too Early For Total Hip Arthroplasty.

INTRODUCTION: Total hip arthroplasty (THA) is often performed in symptomatic patients who have hip dysplasia and do not qualify for periacetabular osteotomy (PAO). The impact of osteoarthritis (OA) severity on postoperative outcomes in dysplasia patients who undergo THA is not well described. We hypothesized that dysplasia patients who have mild OA have slower initial recovery postoperatively, but similar one-year patient-reported outcome measures (PROMs) compared to dysplasia patients who have severe OA. METHODS: We performed a retrospective review at a single academic institution over a six-year period of patients who have dysplasia who underwent THA compared to patients who have primary OA who underwent THA. There were 263 patients who had dysplasia were compared to 1,225 THA patients who did not have dysplasia. Within the dysplasia cohort, we compared PROMs stratified by dysplasia and OA severity. The diagnosis of dysplasia was verified using the radiographic lateral center edge angle (LCEA). A minimum one-year follow-up was required. The PROMs were collected through one year postoperatively. Logistic and linear regression models were used, adjusting for age, sex, body mass index, and Charlson comorbidity index. RESULTS: No significant differences were found in postoperative PROMs or revision rates (P = 0.58). When stratified by dysplasia severity, patients who had lower LCEA had more improvement in physical function scores from pre-operative to 2-weeks (P < 0.01) and higher physical function scores at 2-weeks (P = 0.03). When stratified by OA severity, patients who had a worse Tönnis score had more improvement in physical function scores from pre-operative to 2 weeks (P < 0.01). Recovery curves in dysplasia patients based on dysplasia and OA severity were not significantly different at 6-weeks, 1-year, and 2-years post-operative. CONCLUSION: Patients who had hip dysplasia and mild OA had similar recovery curves compared to those who had severe OA or who did not have dysplasia. We believe that THA is a reasonable surgical intervention for symptomatic dysplasia patients who have mild arthritis and do not qualify for PAO.

Outpatient Total Joint Arthroplasty at a High-Volume Academic Center: An Analysis of Failure to Launch.

BACKGROUND: Unanticipated failure to discharge home (failure to launch, FTL) following scheduled same-day discharge (SDD) total joint arthroplasty (TJA) is problematic for the surgical facility with respect to staffing, care coordination, and reimbursement concerns. The aim of this study was to review rates, etiologies, and contributing factors for FTL in SDD TJA at an inpatient academic medical center. METHODS: All patients who underwent primary TJA between February 2021 and February 2023 were retrospectively reviewed. Of those scheduled for SDD, risk factors for FTL were compared with successful SDD. Readmission and emergency department (ED) visits were compared with historical cohorts. There were 3,093 consecutive primary joint arthroplasties performed, of which 2,411 (78%) were scheduled for SDD. RESULTS: Overall, SDD was successful in 94.2% (n = 2,272) of patients who had an FTL rate of 5.8%. Specifically, SDD was successful in 91.4% with total hip arthroplasty, 96.0% with total knee arthroplasty, and 98.6% with unicompartmental knee arthroplasty. Factors that significantly increased the risk of FTL included general anesthesia versus spinal anesthesia (P < .0001), later surgery start time (P < .0001), longer surgical time (P = .0043), higher estimated blood loss (P < .0001), women (P = .0102), younger age (P = .0079), and lower preoperative mental health patient-reported outcomes scores (P = .0039). Readmission and ED visit rates were not higher in the SDD group when compared to historical controls (P = .6830). CONCLUSIONS: With a comprehensive multidisciplinary approach dedicated to improving SDDs at an academic medical center, we have seen successful SDD in nearly 80% of primary TJA, with an FTL rate of 5.8%, and no increased risk of readmission or ED visits. Without adding many personnel, hospital recovery units, or other resources, simple interventions to help decrease FTL have included enhanced preoperative education and expectation settings, improved perioperative communications, reallocating personnel from the inpatient to the outpatient setting, the use of short-acting spinal anesthetics, and earlier scheduled surgery times.

John Charnley Award: A Quantitative Fluoroscopic Tool Improves Acetabular Fragment Positioning in Periacetabular Osteotomy.

BACKGROUND: Radiographic assessment of acetabular fragment positioning during periacetabular osteotomy (PAO) has been linked to hip survivorship. Intraoperative plain radiographs are time and resource intensive, while fluoroscopy can introduce image distortion affecting measurement accuracy. Our purpose was to determine whether intraoperative fluoroscopy-based measurements with a distortion correcting fluoroscopic tool improved PAO measurement targets. METHODS: We retrospectively reviewed 570 PAOs; 136 PAOs utilized a distortion correcting fluoroscopic tool, and 434 PAOs performed with routine fluoroscopy, prior to this technology. Lateral center-edge angle (LCEA), acetabular index (AI), posterior wall sign (PWS), and anterior center-edge angle (ACEA) were measured on preoperative standing radiographs, intraoperative fluoroscopic images, and postoperative standing radiographs. Defined target zones of correction were AI: 0-10°, ACEA: 25-40°, LCEA: 25-40°, PWS: negative. Postoperative correction in zones and patient-reported outcomes were compared using chi-square tests and paired t-tests, respectively. RESULTS: The average difference between postcorrection fluoroscopic measurements and 6-week postoperative radiographs was 0.21° for LCEA, 0.01° for ACEA, and -0.07° for AI (all P < .01). The PWS agreement was 92%. The percentages of hips meeting target goals overall improved with the new fluoroscopic tool: 74%-92% for LCEA (P < .01), 72%-85% for ACEA (P < .01), and 69 versus 74% for AI (P = .25), though there was no improvement in PWS (85 versus 85%, P = .92). All patient-reported outcomes except PROMIS Mental Health were significantly improved at most recent follow-up. CONCLUSIONS: Our study demonstrated improved PAO measurements and target goals with the use of a distortion correcting quantitative fluoroscopic real-time measuring device. This value-additive tool gives reliable quantitative measurements of correction without interfering with surgical workflow.

High Survivorship of a Modular Titanium Baseplate Independent of Body Mass Index and Malalignment.

BACKGROUND: Tibial component aseptic loosening remains problematic in primary total knee arthroplasty (TKA). Influential factors include component design, metallurgy, and cement technique. Additionally, reports advocate for longer tibial stem fixation in high body mass index (BMI) patients. We have utilized a single stem length modular titanium baseplate in patients regardless of BMI, bone quality, or malalignment. We report the survivorship of this implant with focus on the impact of elevated BMI and postoperative malalignment. METHODS: We retrospectively reviewed patients who underwent TKA with a single modular titanium baseplate with a cruciate-shaped keel between 2004 and 2018. In total, 2,949 TKAs with a minimum of 1-year follow-up were included. The mean follow-up was 7 years. The primary outcome was component failure stratified by BMI and postoperative malalignment. High viscosity cement was utilized in all cases. Chi-squared and t-tests were used to compare outcome variables across groups. RESULTS: Eighty-five implants (2.8%) were revised with 46 (1.6%) for aseptic loosening. Failure was not associated with BMI, gender, American Society of Anesthesiologists class, or Charlson Comorbidity Index. There was no difference in failure rate by BMI (P = .26) or by malalignment (outside of 3° from neutral mechanical axis) (P = .67). Age was associated with failure as patients with failed TKAs were younger (61 vs 65, P < .01). CONCLUSION: This design of a specific modular titanium base plate with a cruciate-shaped keel and grit blast surface demonstrated 99% survivorship regardless of patient BMI or malalignment over 7-year follow-up period. Consistent cement technique with high viscosity cement indicates that component design remains an important variable impacting survivorship in TKA.

Evaluating the Utility of Using Text Messages to Communicate With Patients During the COVID-19 Pandemic.

INTRODUCTION: We evaluated the use of text messages to communicate information to patients whose surgeries were postponed because of the COVID-19 restriction on elective surgeries. Our hypothesis was that text messaging would be an effective way to convey updates. METHODS: In this observational study, 295 patients received text messaging alerts. Eligibility included patients who had their surgery postponed and had a cell phone that received text messages. Engagement rates were determined using embedded smart links. Patient survey responses were collected. RESULTS: A total of 3,032 texts were delivered. Engagement rates averaged 90%. Survey responses (n = 111) demonstrated that 98.2% of patients liked the text messages and 95.5% said that they felt more connected to their care team; 91.9% of patients agreed that the text updates helped them avoid calling the office. Patients with higher pain levels reported more frustration with their surgery delay (5.3 versus 2.8 on 1 to 10 scale, P value < 0.01). More frustrated patients wished they received more text messages (24.4% versus 4.6%, P value = 0.04) and found the content less helpful (8.2 versus 9.2 on 1 to 10 scale, P value = 0.01). CONCLUSION: Text messaging updates are an efficient way to communicate with patients during the COVID-19 pandemic.

Brief preoperative mind-body therapies for total joint arthroplasty patients: a randomized controlled trial.

ABSTRACT: Although knee and hip replacements are intended to relieve pain and improve function, up to 44% of knee replacement patients and 27% of hip replacement patients report persistent postoperative joint pain. Improving surgical pain management is essential. We conducted a single-site, 3-arm, parallel-group randomized clinical trial conducted at an orthopedic clinic, among patients undergoing total joint arthroplasty (TJA) of the hip or knee. Mindfulness meditation (MM), hypnotic suggestion (HS), and cognitive-behavioral pain psychoeducation (cognitive-behavioral pain psychoeducation) were each delivered in a single, 15-minute group session as part of a 2-hour, preoperative education program. Preoperative outcomes-pain intensity, pain unpleasantness, pain medication desire, and anxiety-were measured with numeric rating scales. Postoperative physical functioning at 6-week follow-up was assessed with the Patient-Reported Outcomes Measurement Information System Physical Function computer adaptive test. Total joint arthroplasty patients were randomized to preoperative MM, HS, or cognitive-behavioral pain psychoeducation (n = 285). Mindfulness meditation and HS led to significantly less preoperative pain intensity, pain unpleasantness, and anxiety. Mindfulness meditation also decreased preoperative pain medication desire relative to cognitive-behavioral pain psychoeducation and increased postoperative physical functioning at 6-week follow-up relative to HS and cognitive-behavioral pain psychoeducation. Moderation analysis revealed the surgery type did not differentially impact the 3 interventions. Thus, a single session of a simple, scripted MM intervention may be able to immediately decrease TJA patients' preoperative clinical symptomology and improve postoperative physical function. As such, embedding brief MM interventions in surgical care pathways has the potential to improve surgical outcomes for the millions of patients receiving TJA each year.

Does the sequential addition of accelerometer-based navigation and sensor-guided ligament balancing improve outcomes in TKA?

AIMS: A significant percentage of patients remain dissatisfied after total knee arthroplasty (TKA). The aim of this study was to determine whether the sequential addition of accelerometer-based navigation for femoral component preparation and sensor-guided ligament balancing improved complication rates, radiological alignment, or patient-reported outcomes (PROMs) compared with a historical control group using conventional instrumentation. METHODS: This retrospective cohort study included 371 TKAs performed by a single surgeon sequentially. A historical control group, with the use of intramedullary guides for distal femoral resection and surgeon-guided ligament balancing, was compared with a group using accelerometer-based navigation for distal femoral resection and surgeon-guided balancing (group 1), and one using navigated femoral resection and sensor-guided balancing (group 2). Primary outcome measures were Patient-Reported Outcomes Measurement Information System (PROMIS) and Knee injury and Osteoarthritis Outcome (KOOS) scores measured preoperatively and at six weeks and 12 months postoperatively. The position of the components and the mechanical axis of the limb were measured postoperatively. The postoperative range of motion (ROM), haematocrit change, and complications were also recorded. RESULTS: There were 194 patients in the control group, 103 in group 1, and 74 in group 2. There were no significant differences in baseline demographics between the groups. Patients in group 2 had significantly higher baseline mental health subscores than control and group 1 patients (53.2 vs 50.2 vs 50.2, p = 0.041). There were no significant differences in any PROMs at six weeks or 12 months postoperatively (p > 0.05). There was no difference in the rate of manipulation under anaesthesia (MUA), complication rates, postoperative ROM, or blood loss. There were fewer mechanical axis outliers in groups 1 and 2 (25.2%, 14.9% respectively) versus control (28.4%), but this was not statistically significant (p = 0.10). CONCLUSION: The sequential addition of navigation of the distal femoral cut and sensor-guided ligament balancing did not improve short-term PROMs, radiological outcomes, or complication rates compared with conventional techniques. The costs of these added technologies may not be justified. Cite this article: Bone Joint J 2020;102-B(6 Supple A):24-30.

Revisiting the role of isolated polyethylene exchange for aseptic failures in total knee arthroplasty.

BACKGROUND: Controversy continues to exist regarding the advisability of isolated polyethylene exchange (IPE) following total knee arthroplasty (TKA) for aseptic indications. We sought to compare the difference in the cumulative incidence of reoperation after IPE specifically for aseptic failure and to evaluate risk factors for failure. METHODS: We performed a retrospective cohort study of 122 knees revised for aseptic failure. Reasons for IPE in aseptic knees included: instability, polyethylene wear, arthrofibrosis, patella fracture, patellar resurfacing, patellar maltracking, extensor mechanism failure, patellectomy, and a custom polyethylene for correction of valgus deformity. The relatively high rate of mortality warranted a competing risk model to evaluate the cumulative incidence reoperation. Follow-up time was defined by years from IPE to date of reoperation or last follow-up. Generalized estimating equations were used for comparisons. RESULTS: Our analysis demonstrated an 87% (95% CI, 78-92%) survivorship free of reoperation at five years. Re-revision was secondary to aseptic failure, infection, and patellar malalignment. IPE for polyethylene wear was found to be protective and less likely to require reoperation (SHR 0.121 95% CI: 0.016-0.896, p = 0.039). CONCLUSIONS: The current study suggests that when done for carefully selected indications, IPE may be an acceptable procedure and helpful alternative for aseptic TKA revisions, particularly when the pre-operative diagnosis is polyethylene wear. This is in contrast to prior reports and may represent a need to re-visit the role of isolated polyethylene exchange.

Advantages of an Anterior-Based Muscle-Sparing Approach in Transitioning From a Posterior Approach for Total Hip Arthroplasty: Minimizing the Learning Curve.

BACKGROUND: Enthusiasm for anterior-based approaches for total hip arthroplasty (THA) continues to increase but there is concern for increased complications during the learning curve period associated. This study aimed to investigate if there was a difference in perioperative variables, intraoperative and immediate postoperative complications, or patient-reported outcomes when transitioning from a mini-posterior approach (mPA) to an anterior-based muscle-sparing (ABMS) approach for THA. METHODS: Retrospective cohort study on the first 100 primary THA cases (n = 96 patients) of the senior author (August 2016 to August 2017) using the ABMS approach. These cases were compared to primary THA cases done the year prior (July 2015 to July 2016, n = 91 cases in 89 patients) using an mPA. Data were extracted and analyzed via gamma regression with robust standard errors and using generalized estimating equation regression. RESULTS: We found no difference in the estimated blood loss (P = .452) and surgical time (P = .564) between the cohorts. The ABMS cases had a slightly shorter length of stay (P = .001) with an adjusted mean length of stay of 1.53 days (95% confidence interval 1.4-1.6) compared to 1.85 days (95% confidence interval 1.8-1.9) in the mPA cases. There was no difference in the frequency of immediate postoperative complications (all, P > .05). There was no difference in the adjusted mean change in patient-reported outcomes (all P > .05). In the ABMS group, there was no difference in surgical time or physical function computerized adaptive test between the first 20 cases (reference) and each subsequent group of 20 cases (all P > .05). CONCLUSION: This study demonstrates no associated learning curve for an experienced senior surgeon when switching routine THA approach from mPA to ABMS. We advise careful interpretation of our results, as they may not apply to all surgeons and practices. LEVEL OF EVIDENCE: Level III Therapeutic Study: retrospective comparative study.

Short-term functional recovery after total joint arthroplasty is unaffected by bundled payment participation.

BACKGROUND: Bundled payment models for lower extremity total joint arthroplasty (TJA) aim to improve value by decreasing costs via efficient care pathways. It is unclear how such models affect patient-centered outcomes such as functional recovery. We aimed to determine whether participation in bundled payment for TJA negatively affects patients' functional recovery. METHODS: All patients, regardless of payer, undergoing elective TJA between July 2014 and December 2016 were identified retrospectively and categorized into prebundle (n = 680) and postbundle (n = 1216) cohorts. Mixed-effects linear regression and Wald postests were used to test for differences in patients' functional recovery during the hospital period and over 12 months after TJA between cohorts. We also used multivariate regression to test for differences in hospital length of stay (LOS) and postacute care (PAC) facility use between cohorts. RESULTS: Compared with the prebundle cohort, patients in the postbundle cohort demonstrated a small and nonmeaningful difference in the trajectory of functional recovery in the hospital [χ2(3) = 31.3, P < .01] and no difference in the 12 months after TJA [χ2(3) = 3.9, P = .28]. They had a 0.4-day shorter hospital LOS (95% confidence interval: -0.5, -0.3) and decreased odds for PAC facility use (adjusted odds ratio = 0.3; 95% confidence interval: 0.2, 0.4). CONCLUSIONS: Participation in bundled payment for TJA was not associated with significant changes in patients' functional recovery, an important patient-centered outcome. For the postbundle cohort, hospital LOS and PAC facility use were decreased, consistent with previous studies describing cost-saving strategies in bundled payment. These findings support the need for an ongoing study of the long-term sustainability of these value-based payment models.

Treated Versus Untreated Depression in Total Joint Arthroplasty Impacts Outcomes.

BACKGROUND: To determine if there was a difference in the change in patient-reported physical function (PF) between nondepressed and medically treated depressed or untreated depressed total joint arthroplasty (TJA) patients. METHODS: This is an Institutional Review Board exempt retrospective review of 280 TJA cases from March 2014 to May 2016. Patient-reported PF was measured as part of the routine care via the Patient Reported Outcomes Measurement Information System PF computerized adaptive test. Linear generalized estimating equation regression analyses were used. RESULTS: Untreated depressed cases demonstrated much smaller gains in PF scores compared to nondepressed patients (P = .020). Additionally, although treated and untreated depressed patients had statistically similar preoperative and postoperative PF scores (P > .05), untreated depressed cases experienced a lower magnitude of change (P = .015). CONCLUSION: Medically treated depressed patients may have similar PF gains as nondepressed patients. Larger prospective studies may help identify whether screening for untreated depression and subsequent treatment leads to improved outcomes.

Adding Value to Total Joint Arthroplasty Care in an Academic Environment: The Utah Experience.

BACKGROUND: Adding value in a university-based academic health care system provides unique challenges when compared to other health care delivery models. Herein, we describe our experience in adding value to joint arthroplasty care at the University of Utah, where the concept of value-based health care reform has become an embraced and driving force. METHODS: To improve the value, new resources were needed for care redesign, physician leadership, and engagement in alternative payment models. The changes that occurred at our institution are described. RESULTS: Real-time data and knowledgeable personnel working behind the scenes, while physicians provide clinical care, help move clinical pathway redesigns. Engaged physicians are essential to the successful implementation of value creation and care pathway redesign that can lead to improvements in value. An investment of money and resources toward added infrastructure and personnel is often needed to realize large-scale improvements. Alignment of providers, payers, and hospital administration, including by means of gainsharing programs, can lead to improvements. CONCLUSION: Although significant care pathway redesign efforts may realize substantial initial cost savings, savings may be asymptotic in nature, which calls into question the likely sustainability of programs that incentivize or penalize payments based on historical targets.

Improving Value in Total Joint Arthroplasty: A Comprehensive Patient Education and Management Program Decreases Discharge to Post-Acute Care Facilities and Post-Operative Complications.

BACKGROUND: A step-by-step approach to creating a comprehensive patient education, expectation, and management program is described with the aim of reducing discharges to post-acute care centers (PACs) following total joint arthroplasty (TJA). We hypothesized that by lowering discharges to PACs, readmissions and reoperations would also decrease. METHODS: Following the implementation of a multi-faceted patient education and management program, we retrospectively reviewed 927 TJAs who underwent surgery 12 months before (n = 465) and after (n = 462) the program was implemented. To assess the exposure of the pathway on discharge disposition as well as institutional 30-day and 90-day readmissions and reoperations, a modified Poisson regression was used. RESULTS: There was a 20% absolute reduction in discharges to PACs (<0.001). The frequency of 30-day readmissions was greater in patients who underwent TJA before implementation (incidence rate ratio [IRR] 1.93, 95% confidence interval [CI] 1.01-3.69). The risk for 90-day readmissions (IRR 1.70, 95% CI 1.20-2.40) and reoperations (IRR 1.67, 95% CI 1.12-2.53) was greater prior to implementation. Discharge to PACs was associated with 2.4 and 3.10 times greater risk for 30-day readmissions (95% CI 1.28-4.56) and 30-day reoperations (95% CI 1.40-7.0), respectively. Patients discharged to PACs were also at greater risk for both 90-day readmissions (IRR 1.59, 95% CI 1.08-2.32) and 90-day reoperations (IRR 1.75, 95% CI 1.12-2.73). CONCLUSION: Our program led to a reduction in the number of patients being discharged to PACs following TJA, while also demonstrating a reduction in readmission and reoperations. Additionally, discharge to these facilities was an independent risk factor for these complications.

Challenges in Total Hip Arthroplasty in the Setting of Developmental Dysplasia of the Hip.

BACKGROUND: Developmental dysplasia of the hip (DDH) is a recognized cause of secondary arthritis, which may eventually lead to total hip arthroplasty (THA). An understanding of the common acetabular and femoral morphologic abnormalities will aid the surgeon in preparing for the complexity of the surgical case. METHODS: We present the challenges associated with acetabular and femoral morphologies that may be present in the dysplastic hip and discuss surgical options to consider when performing THA. In addition, common complications associated with this population are reviewed. RESULTS: The complexity of THA in the DDH patient is due to a broad range of pathomorphologic changes of the acetabulum and femur, as well as the diverse and often younger age of these patients. As such, THA in the DDH patient may offer a typical primary hip arthroplasty or be a highly complex reconstruction. It is important to be familiar with all the subtleties associated with DDH in the THA population. The surgeon must be prepared for bone deficiency when reconstructing the acetabulum and should place the component low and medial (at the anatomic hip center), and avoid oversizing the acetabular component. Femoral dysplasia is also complex and variable, and the surgeon must be prepared for different stem choices that allow for decoupling of the metaphyseal stem fit from the implanted stem version. In Crowe III and IV dysplasia, femoral derotation/shortening osteotomy may be required. Many complications associated with THA in the DDH patient may be mitigated with careful planning and surgical technique. CONCLUSION: Performed correctly, THA can yield excellent results in this complex patient population.

Acetabular Wall Indices Help to Distinguish Acetabular Coverage in Asymptomatic Adults With Varying Morphologies.

BACKGROUND: The anterior wall index (AWI) and posterior wall index (PWI) have been proposed to quantify anterior and posterior acetabular coverage using AP pelvic radiographs. However, these indices have only been reported in symptomatic patients with apparent pathomorphologies (dysplasia, overcoverage, and retroversion) undergoing osteochondroplasty or reorientation osteotomy. QUESTIONS: (1) What are the ranges for AWI and PWI from measurements obtained on AP pelvic radiographs of asymptomatic senior athletes with well-functioning hips? (2) Is there a difference between the AWI and PWI in asymptomatic athletes with acetabular morphology consistent with acetabular dysplasia, overcoverage, and retroversion when compared with asymptomatic hips that do not meet the radiographic definitions for those morphologies (controls)? METHODS: Five hundred five athletes (998 asymptomatic native hips) were independently evaluated by two readers on AP pelvic radiographs for AWI and the PWI after excluding hips with prior surgery, inadequate radiographs, or poor function (modified Harris hip score < 80). Hips with a lateral center-edge angle (LCEA) ≥ 20° and ≤ 38° and without acetabular retroversion, based on a positive crossover sign, were used as controls. Hips were categorized as developmental dysplasia of the hip (DDH; undercoverage) if the LCEA was < 20°. Finally, overcoverage was defined as an LCEA > 38°. The mean age of the athletes was 67 years (range, 50-91 years) and 55% were men. Linear generalized estimating equation regression was used to compare each individual diagnosis (DDH, retroversion, overcoverage) with the controls for both AWI and PWI adjusting for age and sex. RESULTS: The mean AWI in the study population was 0.36 (range, -0.02 to 0.91). The mean PWI was 1.13 (range, 0.12-1.74). The mean AWI and PWI in controls (n = 740) was 0.35 (range, -0.02 to 0.91) and 1.13 (range, 0.64-1.70), respectively. There were 25 (3%) with DDH in whom the mean AWI was 0.26 (range, 0.05-0.5) and the mean PWI was 1.03 (range, 0.71-1.3). There were 112 (11%) retroverted hips in whom the mean AWI was 0.42 (range, 0.1-0.89) and PWI was 1.02 (range, 0.61-1.5). There were 121 (12%) overcovered hips in whom the mean AWI was 0.43 (range, -0.18 to 0.85) and PWI was 1.22 (0.12-1.74). The AWI in the control hips was no different than that of DDH hips (ß -0.06; 95% confidence interval [CI], -0.12 to 0.002; p = 0.059) but was found to be lower than retroverted hips (ß 0.08; 95% CI, 0.04-0.11; p < 0.001) and overcovered hips (ß 0.05; 95% CI, 0.03-0.08; p < 0.001). The PWI in control hips was greater than that of DDH hips (ß -0.08; 95% CI, -0.14 to -0.02; p = 0.013) and retroverted hips (ß -0.07; 95% CI, -0.11 to -0.04; p < 0.001) but was less than overcovered hips (ß 0.07; 95% CI, 0.04-0.10; p < 0.001). CONCLUSIONS: The measurements of AWI and PWI in well-functioning, asymptomatic hips may be useful in assessing anterior and posterior acetabular coverage because it was able to distinguish between different types of known pathologic morphology. Despite evidence of these morphologic variances, these senior athletes continued to function at a high level. Thus, the identification of morphologic variance was not consistent with signs of pathology, which further supports that early screening of morphology may not predict the development of symptomatic pathology. Future work should focus on comparing these indices for morphologic variance in both symptomatic and asymptomatic hips to determine whether these measurements can be used in identifying problematic hips and as reference ranges for surgical correction. LEVEL OF EVIDENCE: Level III, diagnostic study.

Operative Fluoroscopic Correction Is Reliable and Correlates With Postoperative Radiographic Correction in Periacetabular Osteotomy.

BACKGROUND: Intraoperative fluoroscopy is commonly used to both guide the osteotomy and judge correction of the acetabular fragment in periacetabular osteotomy (PAO). Prior studies that have compared intraoperative fluoroscopic correction with postoperative radiographic correction were small studies that did not report intra- or interreader reliability. QUESTIONS/PURPOSES: (1) What is the correlation between intraoperative fluoroscopic correction in PAO compared with the correction seen on postoperative radiographs? (2) What is the reliability of radiographic measures of correction in PAO? METHODS: We performed a retrospective study of 121 patients (141 hips) who underwent PAO for symptomatic hip dysplasia at a tertiary referral center. Patients were included in the study if they had preoperative radiographs, intraoperative fluoroscopy, and minimum 6-week postoperative radiographs. Of the 272 PAO procedures performed in this time period, 61 patients who underwent PAO for retroversion and five patients with a history of Perthes disease were excluded as a result of the inability for these radiographic measures to judge fragment correction in PAOs for retroversion and the difficulty in measurement in post-Perthes deformity. Of the 206 PAOs performed for symptomatic acetabular dysplasia, 65 (32%) could not be analyzed because they lacked appropriate preoperative films, leaving 141 PAOs in 121 patients for analysis. The patients lacking appropriate preoperative films had them performed at an outside facility or had plain films that have since been destroyed. The lateral center-edge angle (LCEA) and acetabular index (AI) on the fluoroscopic views and postoperative radiographs were measured by two authors. The concordance between the amount of correction on intraoperative fluoroscopy and minimum 6-week postoperative measurements was analyzed using the concordance correlation coefficient (rc) and a Bland-Altman analysis. Intra- and interrater reliability was calculated between measurements. RESULTS: The amount of intraoperative correction of LCEA as measured on fluoroscopic images demonstrated substantial agreement with postoperative radiographs (rc = 0.79; 95% confidence interval [CI], 0.73-0.85; p < 0.001) as did the AI (rc = 0.77; 95% CI, 0.70-0.84; p < 0.001). The mean difference between intraoperative correction was only -0.38° (SD 3.6°) for LCEA and -0.84° (SD 3.4°) for AI. Interrater reliability for both LCEA and AI also demonstrated substantial agreement (all, rc = 0.70-0.90) for preoperative, operative, and postoperative imaging. Furthermore, intrarater reliability for both LCEA and AI demonstrated almost perfect agreement for all measures (all, rc > 0.81). CONCLUSIONS: Intraoperative fluoroscopy is an accurate and reliable measure of correction of lateral coverage of the acetabular fragment during PAO. Further studies on measures of anterior coverage and acetabular version are needed to validate intraoperative fluoroscopic correction in these planes. LEVEL OF EVIDENCE: Level III, diagnostic study.

Femoral Morphology in Patients Undergoing Periacetabular Osteotomy for Classic or Borderline Acetabular Dysplasia: Are Cam Deformities Common?

BACKGROUND: The primary purpose of our study was to determine the prevalence of Cam deformity in patients with symptomatic acetabular dysplasia (SAD) who underwent periacetabular osteotomy (PAO). METHODS: We retrospectively reviewed 164 SAD PAO patients from 2 institutions. Preoperative anteroposterior and frog-lateral radiographs were analyzed for lateral center edge angle (LCEA), retroversion, alpha angles, and anterior femoral head-neck offset. Hips were classified as dysplastic (LCEA <20°, group A, n = 142) and borderline dysplastic (LCEA 20°-25°, group B, n = 22). There were 128 females and 36 males with an average age of 29 years (range 13-56). RESULTS: The overall prevalence of Cam deformity was 10% (17 of 164) in SAD patients. There was no difference in the prevalence of Cam deformity between the groups (P > .99). CONCLUSION: Prevalence of Cam deformities in our series of SAD patients having undergone PAO is less than prior reports. Careful radiographic measurement should be performed to avoid overtreating these hips with unnecessary osteochondroplasty procedures.

The 2015 Frank Stinchfield Award: Radiographic Abnormalities Common in Senior Athletes With Well-functioning Hips but Not Associated With Osteoarthritis.

BACKGROUND: It is not known whether morphological abnormalities of the hip are compatible with lifelong hip function and avoidance of osteoarthritis (OA). Our purpose was to investigate the prevalence of radiographic findings consistent with femoroacetabular impingement (FAI) and dysplasia (DDH) in senior athletes with well-functioning hips. QUESTIONS/PURPOSES: (1) What is the prevalence of FAI and DDH in senior athletes with well-functioning hips? (2) Are radiographic findings of FAI and DDH associated with OA? (3) Is a history of longer duration or more intense activity associated with hip pathomorphology? (4) Were the modified Harris hip scores and the Hip Outcome Scores lower (legacy scales) in patients with evidence of hip pathomorphology than those without? METHODS: Five hundred forty-seven individuals (55% men, 45% women; 1081 hips, 534 bilateral and 13 unilateral), mean age 67 years (SD 8 years), gave consent and qualified for this institutional review board-approved cross-sectional study of senior athletes. Hips were independently evaluated for radiographic signs of FAI, DDH, and OA. Additionally, a lifetime activities questionnaire and outcome instruments were used to assess pain and function. Hips that had previously undergone arthroplasty or fracture surgery were excluded. RESULTS: Eighty-three percent (898 of 1081) of hips had radiographic abnormalities consistent with FAI, of which 67% (599 of 898) were cam-type FAI. Ten percent (103 of 1081) of hips had radiographic evidence for dysplasia. Radiographic findings of FAI were not predictive of OA after controlling for age and sex (odds ratio [OR], 1.79; 95% confidence interval [CI], 0.48-6.62; p = 0.390). Similarly, radiographic findings of DDH were not predictive of OA (OR, 1.48; 95% CI, 0.31-7.21; p = 0.62). Our data suggest an increased risk of FAI-type morphologies in athletes who participated in competitive sporting events during early adult years (OR, 1.49; 95% CI, 1.04-2.11; p = 0.020). Additionally, participants who reported lifetime participation in competitive sports were at an increased risk of OA compared with those who did not (OR, 1.75; 95% CI, 1.14-2.69; p = 0.007). There were no differences in outcome scores between athletes with and without morphologic abnormalities. CONCLUSIONS: Radiographic findings consistent with FAI in these senior athletes were common and were not associated with the presence of OA. These data suggest that the need to screen for asymptomatic young athletes for radiographic evidence of FAI and DDH may not be necessary. LEVEL OF EVIDENCE: Level III, prognostic study.

Can Radiographs Predict the Use of Modular Stems in Developmental Dysplasia of the Hip?

BACKGROUND: Abnormal anatomy frequently results in the use of a modular stem in patients undergoing primary total hip arthroplasty (THA) for developmental dysplasia of the hip (DDH). However, because these stems are not always available in the operating room, it would be helpful if standard radiographic views could be analyzed in such a way that patients whose femoral anatomy might call for stem modularity could be anticipated before surgery. To our knowledge, no such parameters have been defined. QUESTIONS/PURPOSES: In the senior author's practice, we used femoral neck anteversion of more than 25° as a determinant for use of a modular stem. Given this criterion, we asked if we could reliably identify plain film radiographic parameters of the femur that predict the use of modular stems. We looked at the following: (1) the neck-shaft angle based on the anteroposterior (AP) radiograph (alpha); (2) the neck-shaft angle from the crosstable lateral radiograph (beta); and (3) the calculated femoral anteversion angle. METHODS: We reviewed preoperative radiographs from 50 of 67 patients (79 hips) who had a primary diagnosis of DDH and underwent primary THA from January 1999 to February 2007 inclusive. Hips with prior femoral-sided surgery (n = 2) or without preoperative films (n = 19) were excluded. Furthermore, patients with bilateral hips had the second hip excluded (n = 8). Twenty-one of 50 received a modular femoral stem based on the criterion of intraoperative neck-shaft anteversion of greater than 25° as measured by the senior surgeon (CLP), whereas the remainder received tapered nonmodular stems. There were no differences in age, sex, height, or weight between the modular stem group and tapered stem group. Radiographs were evaluated to record the parameters listed. RESULTS: Patients in whom modular femoral stems were used had a greater mean AP (alpha) neck-shaft angle compared with patients who received tapered nonmodular stem (152°; 95% confidence interval [CI], 146°-157° versus 137°; 95% CI, 134°-141°; p < 0.001) with an optimal cutoff point for determining the use of modular stems of ≥ 142° (receiver operating characteristic [ROC] area = 73%). Hips in which modular femoral stems were chosen had a smaller mean lateral (beta) neck-shaft angle (152°; 95% CI, 148°-157° versus 161°; 95% CI, 158°-164°; p = 0.003) with an optimal cutoff point of ≤ 153° (ROC area = 65%). Hips in which modular femoral stems were used had a higher femoral anteversion angle (mean 45°; 95% CI, 37°-54° versus 21°; interquartile range, 17°-25°; p < 0.001) with an optimal cutoff of ≥ 32° (ROC area = 80%). CONCLUSIONS: Preoperative radiographs anticipated the use of modular stems during THA for DDH in a practice where modular stems were chosen on the basis of a neck-shaft angle of greater than 25° measured at surgery. We found that this could be predicted on preoperative radiographs based on smaller lateral neck-shaft angles, steeper AP radiographic neck-shaft angles, and increased femoral anteversion calculated using these angles. Prospective studies are needed to better determine if these cutoff values adequately predict the use of modular stems.