Is It Necessary to Obtain Lateral Pelvic Radiographs in Flexed Seated Position for Preoperative Total Hip Arthroplasty Planning?

Background: Many of the current total hip arthroplasty (THA) planning tools only consider sagittal pelvic tilt in the standing and relaxed sitting positions. Considering that the risk of postoperative dislocation is higher when bending forward or in sit-to-stand move, sagittal pelvic tilt in the flexed seated position may be more relevant for preoperative planning. We hypothesized that there was a significant difference in sagittal pelvic tilt between the relaxed sitting and flexed seated positions as measured by the sacral slope in preoperative and postoperative full-body radiographs. Methods: This was a multicenter retrospective analysis of the preoperative and postoperative simultaneous biplanar full-body radiographs of 93 primary THA patients in standing, relaxed sitting, and flexed seated positions. The sagittal pelvic tilt was measured using the sacral slope relative to the horizontal line. Results: The mean difference between the preoperative sacral slope in the relaxed sitting position and the flexed seated position was 11.3° (-13° to 43°) (P < .0001). This difference was >10° in 52 patients (56%) and >20° in 18 patients (19.4%). The mean difference between the postoperative sacral slope in a relaxed sitting position and the sacral slope in a flexed seated position was 11.3° (P < .0001). This difference was >10° in 51 patients (54.9%) and >30° in 14 patients (15.1%) postoperatively. Conclusions: There was a significant difference in sagittal pelvic tilt between the relaxed and flexed seated positions. A flexed seated view provides valuable information that might be more relevant for preoperative THA planning in order to prevent postoperative THA instability.

Patient perception of leg length after total hip arthroplasty does not correlate with sagittal lumbar spine stiffness, history of spinal pathology or fusion.

PURPOSE: Although spinal pathology or fusion can change patients' posture and pelvic orientation, their correlation with perception of limb length discrepancy (LLD) after total hip arthroplasty (THA) is not well understood. We hypothesised that LLD perception after THA would not correlate with a history of spinal pathology, fusion or sagittal lumbar spine stiffness among patients who underwent THA. METHODS: Four hundred consecutive patients who underwent THA and had a complete set of anteroposterior and lateral EOS® imaging in standing and sitting positions were included in this retrospective case-control study. All patients underwent THA between 2011 and 2020. Sagittal lumbar spine stiffness was measured by changes in lumbar lordosis and sacral slope from the standing to the sitting position (lumbar spine stiffness: standing sacral slope-sitting sacral slope < 10°). Anatomical and functional lower extremity length, change in the centre of hip rotation, coronal and sagittal knee alignment, and hindfoot height were measured. Multiple logistic regression was used to investigate the correlation between patient perceptions of LLD, and the variables found to be significant in the univariate analysis. RESULTS: There was a substantial difference between the patients with and without LLD perceptions regarding axial pelvic rotation (p = 0.001), knee flexum-recurvatum (p = 0.007) and hindfoot height (p = 0.004). There was no significant difference between patients with and without LLD perceptions regarding differences in femoral length (p = 0.06), history of spine pathology or fusion (p = 0.128) and lumbar spine stiffness (p = 0.955). CONCLUSIONS: Our study found no significant correlation between perceptions of LLD after THA and spinal fusion or lumbar spine stiffness. Changes in the position of the centre of hip rotation can affect the functional leg length. Surgeons should consult patients regarding other factors, such as knee alignment or hind-/midfoot pathologies, as well as compensatory mechanisms, such as axial pelvic rotation, that could affect perceptions of LLD.

Low pelvic incidence is a risk factor for intraoperative complications in minimally invasive anterolateral approach for total hip arthroplasty.

BACKGROUND: Minimally invasive anterolateral approach (ALA) has gained popularity in recent years as better postoperative functional recovery and lower risk of postoperative dislocation are claimed. However, difficulties for femur exposure and intraoperative complications during femoral canal preparation and component placement have been reported. This study analyses the effect of anatomical factors on difficulties for femoral access and intraoperative complications with a modified minimally invasive ALA. MATERIAL AND METHODS: 310 consecutive patients who had primary unilateral total hip arthroplasty (THA) by single surgeon using same approach and technique, and being suitable for EOS were included. All patients underwent pre- and postoperative standing and sitting full-body EOS acquisitions and pelvic and femoral parameters were measured. All intra- and postoperative complications for femoral preparation and implantation were assessed. Intraoperative complications included femoral fractures and difficulties for femoral exposure. RESULTS: 10 patients (3.2%) had intraoperative femoral fractures (2 greater trochanter, 8 calcar). Difficult access to the proximal femur was reported for 10 other patients (3.2%). Patients with intraoperative complications presented a significantly lower pelvic incidence (PI) than patients without intraoperative complications (mean PI: 39.4° vs. 56.9°, p < 0.001). CONCLUSIONS: The pelvic incidence can be useful to detect anatomically less favourable patients for THA implantation using ALA.

How much change in pelvic sagittal tilt can result in hip dislocation due to prosthetic impingement? A computer simulation study.

Developing spinal pathologies and spinal fusion after total hip arthroplasty (THA) can result in increased pelvic retroversion (e.g., flat back deformity) or increased anterior pelvic tilt (caused by spinal stenosis, spinal fusion or other pathologies) while bending forward. This change in sagittal pelvic tilt (SPT) can result in prosthetic impingement and dislocation. Our aim was to determine the magnitude of SPT change that could lead to prosthetic impingement. We hypothesized that the magnitude of SPT change that could lead to THA dislocation is less than 10° and it varies for different hip motions. Hip motion was simulated in standing, sitting, sit-to-stand, bending forward, squatting and pivoting in Matlab software. The implant orientations and SPT angle were modified by 1° increments. The risk of prosthetic impingement in pivoting caused by increased pelvic retroversion (reciever operating characteristic [ROC] threshold as low as 1-3°) is higher than the risk of prosthetic impingement with increased pelvic anteversion (ROC threshold as low as 16-18°). Larger femoral heads decrease the risk of prosthetic impingement (odds ratio {OR}: 0.08 [932 mm head]; OR: 0.01 [36 mm head]; OR: 0.002 [40 mm head]). Femoral stems with a higher neck-shaft angle decrease the prosthetic impingement due to SPT change in motions requiring hip flexion (OR: 1.16 [132° stem]; OR: 4.94 [135° stem]). Our results show that overall, the risk of prosthetic impingement due to SPT change is low. In particular, this risk is very low when a larger diameter head is used and femoral offset and length are recreated to prevent bone on bone impingement.

Is Combined Anteversion Equally Affected by Acetabular Cup and Femoral Stem Anteversion?

BACKGROUND: To create a safe zone, an understanding of the combined femoral and acetabular mating during hip motion is required. We investigated the position of the femoral head inside the acetabular liner during simulated hip motion. We hypothesized that cup and stem anteversions do not equally affect hip motion and combined hip anteversion. METHODS: Hip implant motion was simulated in standing, sitting, sit-to-stand, bending forward, squatting, and pivoting positions using the MATLAB software. A line passing through the center of the stem neck and the center of the prosthetic head exits at the polar axis (PA) of the prosthetic head. When the prosthetic head and liner are parallel, the PA faces the center of the liner (PA position = 0, 0). By simulating hip motion in 1-degree increments, the maximum distance of the PA from the liner center and the direction of its movement were measured (polar coordination system). RESULTS: The effect of modifying cup and stem anteversion on the direction and distance of the PA's change inside the acetabular liner was different. Stem anteversion influenced the PA position inside the liner more than cup anteversion during sitting, sit-to-stand, squatting, and bending forward (P = .0001). This effect was evident even when comparing stems with different neck angles (P = .0001). CONCLUSION: Cup anteversion, stem anteversion, and stem neck-shaft angle affected the PA position inside the liner and combined anteversion in different ways. Thus, focusing on cup orientation alone when assessing hip motion during different daily activities is inadequate.

Sagittal Spinopelvic Translation Is Combined With Pelvic Tilt During the Standing to Sitting Position: Pelvic Incidence Is a Key Factor in Patients Who Underwent THA.

BACKGROUND: Sagittal spinopelvic translation (SSPT) is the horizontal distance from the hip center to the C7 plumb line (C7PL). SSPT is an important variable showing the overall patient balance in different functional positions which could affect the rate of hip instability. This study investigates the SSPT modification in patients who underwent total hip arthroplasty (THA). METHODS: A total of 120 patients were assessed preoperatively and postoperatively on standing and sitting acquisitions (primary unilateral THA without complication). SSPT is zero when the C7PL goes through the center of the femoral heads and positive when the C7PL is posterior to the hips' center (negative if anterior). Three subgroups were defined based on the pelvic incidence (PI): low PI <45°, 45°< normal PI <65°, or high PI >65°. RESULTS: The overall mean preoperative SSPT change from standing to sitting was 2.2 cm ([-7.2 to 17.4]) (P < .05). The overall mean postoperative SSPT change from standing to sitting was 1.2 cm ([-14.2 to 22.4]) (P < .05). In low- and normal-PI groups, standing to sitting SSPT and preoperative to postoperative changes in standing SSPT were increased significantly after surgery with the C7PL behind the hips' center (P < .05). In the high-PI group, standing to sitting SSPT was increased postoperatively (P = .034) (no significant changes from preoperative to postoperative status in standing and sitting). CONCLUSIONS: Adaptation from standing to sitting positions combines pelvic tilt and anteroposterior pelvic translation. THA implantation induces significant changes in SSPT mainly for low- and standard-PI patients. This is an important variable to consider when investigating the causes of THA subluxation or dislocation.

How do global sagittal alignment and posture change after total hip arthroplasty?

BACKGROUND: Postural change after total hip arthroplasty (THA) is still a matter of discussion. Previous studies have mainly concentrated on the pelvic motions. We report the post-operative changes of the global sagittal posture using pelvic, spinal, and lower extremities parameters. METHODS: 139 patients (primary THA, without previous spinal or lower extremity surgery) were included. We measured pelvic parameters [SS, sacral slope; PI, pelvic incidence; PT, pelvic tilt; APP angle, anterior pelvic plane angle] and the global posture parameters (SVA, sagittal vertical angle; GSA, global sagittal angle; TPA, T1 pelvic angle). Patients were categorized into low PI group < 45°, 45° < medium PI < 65°, and high PI > 65°. RESULTS: Mean GSA and SVA decreased post-operatively (p = 0.005 and p = 0.004 respectively). The TPA change was not significant (p = 0.078). In the low PI group, GSA (5.4 ± 5.0 to 4.3 ± 4.0, p = 0.005) and SVA (5.4 ± 4.9 to 4.2 ± 4.1, p = 0.038) decreased with more posterior pelvic tilt. Post-operative TPA was significantly higher (8.4 ± 10.6 to 9.8 ± 10.7; p = 0.048). In the medium PI group, SVA decreased (4.2 ± 4.6 to 3.6 ± 4.5, p = 0.020) with more posterior pelvic tilt. In the high PI group, pelvic and global posture parameters did not evolve significantly. CONCLUSION: PI is the key determining factor in pelvic tilt modification after THA. Patients with low PI demonstrate significant modification in spine, pelvic, and lower extremities. Pelvic tilt is the main adaptation mechanism for medium incidence patients whereas pelvic tilt does not change in high PI patients after surgery.

Post-operative urinary retention after lower extremity arthroplasty and the peri-operative role of selective alpha-1 adrenergic blocking agents in adult male patients: a propensity-matched retrospective cohort study.

PURPOSE: The purpose of this study was to determine whether male patients taking pre-operative selective alpha-1 adrenergic blocking agents have a lower likelihood of developing post-operative urinary retention (POUR) and a shorter length of hospitalization following lower extremity arthroplasty. METHODS: A retrospective cohort study was conducted of patients who underwent primary or revision total hip or knee arthroplasty, or unicompartmental knee arthroplasty at an academic institution from January 2002 to May 2014. A cohort of male patients aged 35 and older who were taking a selective alpha-1 blocker prior to surgery (N = 229) were compared with a control group (N = 330) not taking one of these medications. Propensity score-matched logistic regression was performed to isolate the effect of taking a selective alpha-1 blocker on POUR. RESULTS: When evaluating for the outcome of POUR while controlling for age, hypertension, benign prostatic hyperplasia, urinary tract infections, type of anaesthesia, and procedure, those patients taking an alpha-1 blocker had a 12.1% decreased relative risk (95% CI 3.4 to 20.8%; p = 0.007) of developing POUR compared with patients not taking these medications. Mean length of stay was 3.8 days (95% CI 3.6 to 4.1) in the cohort taking selective alpha-1 blockers compared with 4.7 days (95% CI 4.4 to 4.9) for the control cohort. CONCLUSIONS: After controlling for known risk factors for the development of POUR, the use of selective alpha-1 blockers pre-operatively reduces the risk of developing urinary retention after lower extremity arthroplasty and is associated with a 1-day decreased length of stay.

The AAHKS Clinical Research Award: Prophylactic Tamsulosin Does Not Reduce the Risk of Urinary Retention Following Lower Extremity Arthroplasty: A Double-Blinded Randomized Controlled Trial.

BACKGROUND: Postoperative urinary retention (POUR) is common. Selective alpha-1 adrenergic antagonists, such as tamsulosin, are effective for treating urinary retention. The purpose of this study is to determine whether perioperative prophylactic tamsulosin reduces the incidence of POUR following total hip and knee arthroplasty. METHODS: Male patients 35 years of age and older undergoing primary total hip or knee arthroplasty at a single center from 2015 to 2018 were eligible for inclusion. Patients were randomized to receive tamsulosin 0.4 mg or placebo daily for 5 days preoperatively, the morning of surgery, and the first postoperative day. The incidence of POUR was determined during the postoperative hospitalization. RESULTS: A total of 176 patients were enrolled in the study. Two patients were withdrawn prior to randomization. The remaining 174 were randomized to tamsulosin (n = 87) or placebo (n = 87). After an additional 43 patients were withdrawn prior to surgery, 131 patients completed the study (tamsulosin, n = 64; placebo, n = 67). A total of 42 patients (32.1%) developed POUR, with 18 cases (28.1%) in the tamsulosin group and 24 cases (35.8%) in the placebo group (P = .345), resulting in an odds ratio of 0.701 and a risk difference of 7.69%. CONCLUSION: Prophylactic tamsulosin did not reduce the incidence of POUR after hip and knee arthroplasty compared to placebo. The odds ratio indicates an approximately 30% decreased odds of developing POUR in the tamsulosin group, albeit not statistically significant. Tamsulosin does not appear to be effective as a prophylactic measure for reducing POUR in male hip and knee arthroplasty patients.

Long-term results of extensor mechanism reconstruction using Achilles tendon allograft after total knee arthroplasty.

PURPOSE: Disruption of the extensor mechanism after total knee arthroplasty (TKA) is an infrequent but devastating complication. Presently, limited data exists regarding the optimal treatment and long-term outcomes. METHODS: Patients who underwent reconstruction of their knee extensor mechanism using Achilles tendon allograft following TKA between January 2003 and January 2012 were identified. Sixteen patients with 17 reconstructions (10 patellar tendons, 7 quadriceps tendons) were studied. All patients underwent evaluation at an average of 45.7 months. Ten of the patients were followed to an average of 65.4 months. RESULTS: After reconstruction, the average extensor lag was 6.6° and average knee flexion was 105.1°. Of the patients with a minimum follow-up of two years and an average follow-up of 65.4 months, the average extensor lag and knee flexion was 8.4° and 107.9°, respectively, with quadriceps strength maintained at an average of 4/5. The quadriceps tendon reconstructions had an average extensor lag and flexion of 2.9° and 103°, respectively. The patellar tendon reconstructions, excluding one re-rupture, had an average extensor lag and flexion of 9.6° and 105.1°, respectively. Four patients died during the follow-up period. All but one of the patients were below the mean for age-matched controls on the SF-36. CONCLUSION: Achilles tendon allograft reconstruction is a reliable and durable treatment for patients who sustain not only patellar tendon ruptures, but also quadriceps tendon ruptures following TKA. Despite the success of this technique, the injury and procedure have a profound impact on overall function.

Total Hip Arthroplasty in Patients With Parkinson Disease: Improved Outcomes With Dual Mobility Implants and Cementless Fixation.

BACKGROUND: Parkinson disease (PD) results in severe limitation in ambulation caused by abnormality of gait and posture. The rate of complications, including fractures and dislocation after total hip arthroplasty (THA), can be higher among these patients. The goal of this study was to investigate the long-term outcomes of primary and revision THAs with cementless dual mobility implants. METHODS: This retrospective study examines 59 PD patients who had surgery between 2002 and 2012. All the primary cases were performed for osteoarthritis and all patients received cementless acetabular implants with dual mobility bearing surface. The femoral stem was cemented in 4 patients who underwent revision surgery. The mean follow-up time was 8.3 years (4-14 years). RESULTS: Good to excellent pain relief was achieved in 53 of 57 patients at the 2-year follow-up and in 40 of 47 patients at their latest follow-up. The most common medical complication was cognitive impairment (12 of 57 patients). One patient sustained an intraprosthetic hip dislocation 9 years after surgery, which required revision. Four patients sustained periprosthetic femoral fractures with well-fixed stem, requiring open reduction and internal fixation. The disability had increased in 68% of the patients in the latest follow-up visit. DISCUSSION: Our study shows that elective primary or revision THA using cementless implants with dual mobility bearing surface in patients with PD provides satisfactory long-term outcomes, although many of these patients may see a general worsening of their activities over time due to PD.

Post-operative medical and surgical complications after primary total joint arthroplasty in solid organ transplant recipients: a case series.

PURPOSE: In a series of solid organ transplant (SOT) recipients who underwent a subsequent primary total joint arthroplasty (TJA) procedure, this study aimed to determine: (1) 90-day morbidity and mortality after primary total knee or hip arthroplasty (TKA and THA), (2) overall post-operative infection rates, and (3) how complication and infection rates compared across primary TJA procedure and type of transplant organ. METHODS: The University of Michigan Health System database was retrospectively searched using current procedural terminology codes for any primary TKA or THA performed at the institution in years 2000-2012 in a patient who previously received a successful SOT at any hospital. RESULTS: The search yielded 44 arthroplasties performed in 29 SOT recipients (average age 54.8 years, average follow-up about 30 months for both groups). No deaths were reported, but 13/27 (48.1%) THA patients and 2/6 (33.3%) TKA patients experienced a total of 29 complications within 90 days of surgery. One patient (3.7%) [1/27 patients, 1/37 joints] underwent revision hip arthroplasty to correct limb length. One THA patient and two TKA patients developed infection requiring revision surgery (3.7% and 33%, respectively). Type of transplant did not affect complication rates (P=0.65), and infection was more common after TKA (P=0.01). CONCLUSIONS: A series of SOT recipients demonstrated increased rates of infection and other complications following TJA. Surgical and medical teams should work closely to optimize this population for TJA surgery and minimize peri-operative complications. LEVEL OF EVIDENCE & STUDY DESIGN: Level IV, Prognostic Case-Series.

Previous arthroscopic repair of femoro-acetabular impingement does not affect outcomes of total hip arthroplasty.

BACKGROUND: Total hip arthroplasty (THA) is commonly elected following failed arthroscopic treatment of femoro-acetabular impingement (FAI). The purpose of this study was to evaluate post-operative outcomes of primary THA in patients who had previously undergone arthroscopic treatment for FAI. METHODS: A retrospective, matched case-control study was conducted. The case group included 39 patients who underwent THA after previous hip arthroscopy for FAI. Thirty-nine patients who had a primary THA without previous hip arthroscopy served as a control group and were matched for age, sex and body mass index. Surgical outcomes were assessed based on inpatient hospital metrics and outpatient complication measures. Statistical analyses were performed to identify the significance of outcome variables between case and control groups. RESULTS: No statistically significant differences were observed between groups in terms of operative time, haemoglobin drop, intra-operative estimated blood loss, transfusion requirements, amounts of opioids provided, functional mobility assessments on post-operative days one and two, length of hospitalization, discharge location, emergency department visits, post-operative superficial or deep periprosthetic infection, revision rates for dislocation or formation of heterotopic bone (p-values = 0.1-0.8). A statistically significant difference was found between the walking scores on the third post-operative day (p = 0.015). CONCLUSIONS: These findings, while underpowered, are consistent with other previously published reports. Previous hip arthroscopy for FAI does not appear to impact post-operative outcomes of a subsequent THA. Larger datasets from different surgeons and centers are needed to further assess these conclusions. LEVEL OF EVIDENCE: Case-control level-III.

Are advanced three-dimensional imaging studies always needed to measure the coronal knee alignment of the lower extremity?

BACKGROUND: Coronal malalignment of the lower extremity is closely related to the onset and progression of osteoarthritis. Restoring satisfactory alignment after tibial osteotomy improves the long-term success of this conservative surgery. The purpose of our study was to determine (1) if there is a difference between two-dimensional (2D) and 3D measurements of the hip-knee-ankle (HKA) angle between the mechanical axes of the femur and the tibia, (2) which parameter most affects 2D-3D HKA measurement, and (3) the percentage of patients who are at risk of error in HKA measurement. METHODS: We reviewed imaging studies of the consecutive patients referred to us for hip or knee pain between June and October 2013. Patients with previous pelvis or lower extremity surgery were excluded. RESULTS: In 51 % (95/186) of lower extremities examined, the 3D method showed more valgus than the 2D method, and in 49 % (91/186), the 3D method showed more varus. In 12 % of extremities (23/186), the knee varus or valgus alignment was completely opposite in 3D images compared to 2D images. Having more than 7° of flexum/recurvatum alignment increased error in 2D HKA measurement by 5.7°. This was calculated to be 0.15° per 1° increase in femoral torsion and 0.05° per 1° increase in tibial torsion. Approximately 20 % of patients might be at risk of error in HKA angle measurement in 2D imaging studies. CONCLUSIONS: Orthopaedic surgeons should assess lower extremity alignment in standing position, with enough exposure of the extremity to find severe alignment or rotational deformities, and consider advanced 3D images of those patients who have them. Otherwise, HKA angle can be measured with good accuracy with 2D techniques. LEVEL OF EVIDENCE: Level-III diagnostic.

The global alignment in patients with lumbar spinal stenosis: our experience using the EOS full-body images.

Lumbar stenosis is frequently observed and treated by spine surgeons. The extent of neurological decompression and the potential spinal fixation are the basic concerns when surgery is planned. But this segmented approach to the problem is sometimes insufficient due to the complex functional situations induced by a sagittal imbalance of the patient and the combination of pathologies known as hip-spine or knee-spine syndromes. A total of 373 consecutive patients included from our EOS and clinical data base. Patients were divided in two groups. Group A included patients presenting exclusive spinal issues (172 cases) out of whom 117 (68 %) had sagittal imbalance. Among 201 patients with associated lower limbs issues (group B), 122 (61 %) had sagittal imbalance. The perception of imbalance was noticed in 54 % (93 cases) in group A and 57 % (115 cases) in group B. In the global series of 239 imbalanced cases, the key point was a spine issue for 165 patients (the 117 patients with only spine problems and 48/122 cases with combined spine and lower limbs problems). But in the patients with combined spine and lower limbs problems, we individualized hip-spine syndromes (24/122 patients) and knee-spine syndromes (13/122 patients). In some cases, (37/122 patients) the anatomical and functional situations were more complex to characterize a spine-hip or a hip-spine problem. The EOS full-body images provide new information regarding the global spinal and lower limbs alignment to improve the understanding of the patient functional posture. This study highlights the importance of the lower limb evaluation not only as compensatory mechanism of the spinal problems but also as an individualized parameter with its own influence on the global balance analysis. Level of evidence IV diagnostic case series.

Complicated Outcomes After Emergent Lower Extremity Surgery in Patients With Solid Organ Transplants.

The complications of emergent or urgent surgery in solid organ transplant recipients are unclear. The goal of this nonrandomized retrospective case study, conducted at a large public university teaching hospital, was to determine the following: (1) 90-day postsurgical complications in solid organ transplant recipients who undergo fracture surgery of the lower extremities; (2) 90-day and 1-year mortality rates for this cohort; (3) correlation of particular postsurgical complications with the 90-day or 1-year mortality rate; and (4) correlation of body mass index with the 90-day or 1-year mortality rate. Subjects included 36 solid organ transplant recipients who underwent surgical treatment for 37 emergent or urgent lower extremity fractures within 72 hours of presentation to the emergency department. Patients were followed for all medical and surgical complications for 90 days and for all-cause mortality for 1 year. Within 90 days of surgery, patients had complications that included acute renal failure (15, 40.5%), deep venous thrombosis (3, 8.1%), pulmonary embolus (2, 5.4%), pneumonia (7, 18.9%), superficial surgical site infection (3, 8.1%), and nonorthopedic sepsis (4, 10.8%). In addition, 3 (8.1%) and 5 (13.9%) patients died within 90 days and 1 year, respectively. Hospital readmission correlated with a higher 1-year mortality rate (odds ratio, 14.000; P=.016). Higher body mass index correlated with higher 90-day (odds ratio, 1.425; P=.035) and 1-year (odds ratio, 1.334; P=.033) mortality rates. Solid organ transplant recipients with lower extremity fracture have high 90-day and 1-year mortality rates and may have multiple complications within 90 days of treatment. [Orthopedics. 2016; 39(6):e1063-e1069.].

Do Patients' Perceptions of Leg Length Correlate With Standing 2- and 3-Dimensional Radiographic Imaging?

BACKGROUND: This study compared 2- and 3-dimensional (2D and 3D) radiographic measurements of anatomical and functional leg length and knee coronal and sagittal alignments and correlated these measurements with patients' leg-length perceptions. METHODS: Patients without symptomatic spinal pathology, previous surgery of the spine, and lower extremities (140 lower extremities) were evaluated on EOS images obtained in standing position. Numerous measurements of each limb were compared to the contralateral limb. All 2D/3D measures were evaluated and compared for repeatability and reproducibility. RESULTS: Mean 2D functional and anatomical lengths were 78.7 cm (64.7-88.4, confidence interval [CI] 95%: 77.4-80) and 78.3 cm (64.9-87.9, CI 95%: 77-79.6), respectively. Mean 3D functional and anatomical lengths were 78.9 cm (65.1-88.7, CI 95%: 77.6-80.2) and 78.9 cm (65.6-88.3, CI 95%: 77.8-80.5), respectively (P < .001). Mean 2D and 3D knee varus/valgus angles were -1.9° (-26.4 to 9.1, CI 95%: -3.5 to -0.7) and -0.9° (-19.2 to 11.8, CI 95%: -2.4 to 0.2), respectively (P = .004). Multiple regression analysis found that patients with >10° of flexum/recurvatum were 2.1× more likely to perceive unequal length (P < .1). Patients with irreducible varus/valgus knee deformity were 4× more likely to perceive unequal length (P < .04). CONCLUSION: EOS imaging allows more accurate assessment of anatomical and functional lengths. Patients' perceptions of lower extremity length may correlate more closely with coronal and sagittal alignments of the knee than with femoral or tibial length. This study highlights the importance of physical examination of all the joints and 3D measurements in functional standing position.

Trends in primary and revision knee arthroplasty among orthopaedic surgeons who take the American Board of Orthopaedics part II exam.

PURPOSE: A certified list of all operative cases performed within a six month period is required of surgeons by the American Board of Orthopaedic Surgery (ABOS) as a prerequisite to taking the Part II Oral Examination. Using the data on these cases collected and maintained by ABOS, this study assessed the influence of prior fellowship training in adult reconstruction on the volume and surgeon-reported complication rate of knee joint arthroplasty cases over time. METHODS: All data were self reported to a secure Internet database (SCRIBE) by candidates who applied to take Part II of the ABOS Examination for the first time. This database was searched for all procedures done between 2003 and 2013 with CPT codes for total and revision knee arthroplasty and removal of knee implant (static or dynamic spacer) to determine procedural volumes and early complication rates among Board-eligible orthopaedic surgeons with and without adult reconstructive fellowship training. RESULTS: More than 43,000 knee arthroplasty surgeries were identified. Surgeons who had completed adult reconstruction fellowship training after residency performed 55 % of total knee arthroplasties, averaging 33.5 knee arthroplasties during the six month case-collection period compared to 7.4 procedures by non-fellowship-trained surgeons (p < 0.001). Adult reconstruction fellowship-trained surgeons performed significantly more revisions for infection (average 6.6 versus 2.2 revisions) (p < 0.001). Adult reconstruction fellowship training did not significantly affect complication rates for primary arthroplasty but was associated with an increased complication rate for revisions. Those surgeons who performed more than 100 arthroplasties a year reported significantly fewer complications in primary arthroplasties (12.7 % versus 16.9 %) (p < 0.001). Over time, an increasing percentage of arthroplasties were done by surgeons with adult reconstruction fellowship training. CONCLUSIONS: Adult reconstruction fellowship-trained surgeons performed an increasing number of primary and more complex knee arthroplasties from 2003 to 2013. Surgeons who perform a larger volume of knee arthroplasty surgeries report fewer early complications than surgeons with fewer cases. LEVEL OF EVIDENCE: 4.

High Risk of Failure With Bimodular Femoral Components in THA.

BACKGROUND: The bimodular femoral neck implant (modularity in the neck section and prosthetic head) offers several implant advantages to the surgeon performing THAs, however, there have been reports of failure of bimodular femoral implants involving neck fractures or adverse tissue reaction to metal debris. We aimed to assess the results of the bimodular implants used in the THAs we performed. QUESTIONS/PURPOSES: We asked: (1) What is the survivorship of the PROFEMUR(®) bimodular femoral neck stems? (2) What are the modes of failure of this bimodular femoral neck implant? (3) What are the major risk factors for the major modes of failure of this device? METHODS: Between 2003 and 2009, we used one family of bimodular femoral neck stems for all primary THAs (PROFEMUR(®) Z and PROFEMUR(®) E). During this period, 277 THAs (in 242 patients) were performed with these implants. One hundred seventy were done with the bimodular PROFEMUR(®) E (all are accounted for here), and when that implant was suspected of having a high risk of failure, the bimodular PROFEMUR(®) Z was used instead. One hundred seven THAs were performed using this implant (all are accounted for in this study). All bearing combinations, including metal-on-metal, metal-on-polyethylene, and ceramic-on-ceramic, are included here. Data for the cohort included patient demographics, BMI, implant dimensions, type of articular surface, length of followup, and C-reactive protein serum level. We assessed survivorship of the two stems using Kaplan-Meier curves and determined the frequency of the different modes of stem failure. For each of the major modes of failure, we performed binary logistic regression to identify associated risk factors. RESULTS: Survivorship of the stems, using aseptic revision as the endpoint, was 85% for the patients with the PROFEMUR(®) E stems with a mean followup of 50 months (range, 1-125 months) and 85% for the PROFEMUR(®) Z with a mean followup of 50 months (range, 1-125 months)(95% CI, 74-87 months). The most common modes of failure were loosening (9% for the PROFEMUR(®) E), neck fracture (6% for the PROFEMUR(®) Z and 0.6% for the PROFEMUR(®) E), metallosis (1%), and periprosthetic fracture (1%). Only the bimodular PROFEMUR(®) E was associated with femoral stem loosening (odds ratio [OR] =1.1; 95% CI, 1.04-1.140; p = 0.032). Larger head (OR = 3.2; 95% CI, 0.7-14; p = 0.096), BMI (OR = 1.19; 95% CI, 1-1.4; p = 0.038) and total offset (OR = 1.83; 95% CI, 1.13-2.9; p = 0.039) were associated with neck fracture. CONCLUSION: Bimodular neck junctions may be potentiated by long neck lengths, greater offset, and larger head diameters. These factors may contribute to bimodular neck failure by creating a larger moment about the neck's insertion in the stem. The PROFEMUR(®) E implant is associated with high periprosthetic loosening. Based on our experience we cannot recommend the use of bimodular femoral neck implants. LEVEL OF EVIDENCE: Level III, therapeutic study.

Total Hip Prostheses in Standing, Sitting and Squatting Positions: An Overview of Our 8 Years Practice Using the EOS Imaging Technology.

More total hip arthroplasty (THA) is performed worldwide and especially in younger and more active patients compared to earlier decades. One of the focuses of THA research in the future will be on optimizing the radiological follow-up of these patients using 2D and 3D measurements of implants position while reducing the radiation dose delivered. Low-dose EOS(®) imaging is an innovative slot-scanning radiograph system providing valuable information in patient functional positions (standing, sitting and even squatting positions). EOS has been proven accurate and reliable without significant inconvenience caused by the metallic artifacts of implants. The ability to obtain precise data on implant orientation according to the patient posture opens new perspectives for a comprehensive analysis of the pelvic frontal and sagittal balance and its potential impact on implants function and failures. We report our 8 years experience on our first 300 THA patients using this technology routinely for pre and post op evaluation. Our results will be compared and confronted with the actual literature about this innovative technology. We shall especially emphasize our experience about patients with abnormal posture and the evolution of the subject over time, because the phenomenon of an aging spine is frequently associated with the process of aging hips.