Accuracy of cup placement compared with preoperative surgeon targets in primary total hip arthroplasty using standard instrumentation and techniques: a global, multicenter study.

BACKGROUND: Acetabular cup positioning in total hip arthroplasty (THA) is closely related to outcomes. The literature has suggested cup parameters defined by the Lewinnek safe zone; however, the validity of such measures is in question. Several studies have raised concerns about the benefits of using the Lewinnek safe zone as a predictor of success. In this study we elected to use prospective surgeon targets as the basis for comparison to see how successful surgeons are positioning their cup using standard instruments and techniques. METHODS: A prospective, global, multicenter study was conducted. Cup positioning success was defined as a composite endpoint. Both cup inclination and version needed to be within 10° of the surgeon target to be considered a success. Radiographic analysis was conducted by a third-party reviewer. RESULTS: In 170 subjects, inclination, target versus actual, was 44.8° [standard deviation (SD 0.9°)] and 43.1° (SD 7.6°), respectively (p = 0.0029). Inclination was considered successful in 84.1% of cases. Mean version, target versus actual, was 19.4° (SD 3.9°) and 27.2° (SD 5.6°), respectively (p < 0.0001). Version was considered successful in 63.4% of cases, and combined position (inclination and version) was considered successful in 53.1%. CONCLUSION: This study shows that with traditional methods of placing the cup intraoperatively, surgeons are only accurate 53.1% of the time compared with a predicted preoperative plan. This study suggests that the inconsistency in cup positioning based on the surgeon's planned target is potentially another important variable to consider while using a mechanical guide or in freehand techniques for cup placement in THA. TRIAL REGISTRATION: This study is registered on ClinicalTrials.gov, NCT03189303.

Mid-term survivorship and clinical outcomes of revision knee arthroplasty using a mobile bearing tibial tray: A single-center registry review.

BACKGROUND: Revision total knee arthroplasty can successfully restore function and relieve pain for patients with failed knee replacements. Mobile-bearing implants were designed to provide greater congruency between the implant and the polyethylene insert. The goal of this study was to review the clinical outcomes and survivorship for a revision mobile-bearing tibial design. METHODS: A retrospective outcomes review was conducted to assess survivorship and clinical outcomes for a mobile bearing tibial tray, used with metaphyseal sleeves, in revision total knee arthroplasty. RESULTS: At time of furthest follow-up, KM estimates (95% CI; n with further follow-up) for all-cause revision were 82.5% (75.8%; 87.5%; 42) at 7 years for the clinical assumption (CA), and 88.5% (84.4%,91.6%; 53) at 13 years for the registry assumption (RA). For revision of the tray as the endpoint, survivorship estimates were 93.4% (87.0%,96.7%; 42) at 7 years for CA, and 96.2% (93.2%,97.9%; 53) at 13 years for RA. CONCLUSION: In this single-center registry evaluation, we found excellent mid-term survivorship and clinical outcomes for a mobile-bearing tibial tray used with metaphyseal sleeves in revision total knee arthroplasty.

Early functional recovery outcomes and return to work after primary total hip arthroplasty: a novel patient reported outcomes questionnaire.

PURPOSE: Clinical and patient reported outcomes are often collected before and after the procedure to benchmark and study outcomes for patients. These outcomes and scores are useful for tracking patient outcomes after surgery, however, the fact that these commonly used measures typically provide information about a patient's level of pain and function at a single point in time is a limitation. METHODS: We present early functional recovery and return to work outcomes after primary THA from a novel questionnaire administered in a global, multi-center, prospective clinical study. RESULTS: By 6 and 12 weeks post-op, a large proportion of study subjects were able to perform functional recovery outcomes after their THA: walk without an aid (74%; 94%); drive (76%; 97%); basic activities of daily living (94%; 99%); perform light household duties (91%; 96%); perform moderate-to-heavy household duties (54%; 86%); go up and down a flight of stairs (92%; 99%); put on socks/stockings (77%; 93%); bend down to pick up an object from the floor (87%; 97%); stand up from a chair (96%; 99%); perform leisure recreational activities (54%; 84%); perform primary goal identified pre-THA (69%; 86%). 60% were able to return to work by 12 weeks post-op. These questions showed strong association with the Forgotten Joint Score. CONCLUSION: Excellent patient reported early functional recovery outcomes and satisfaction were observed at 6- and 12-weeks post-op in this cohort and is the first reported data using a novel PRO. CLINICAL TRIAL REGISTRATION: NCT03189303, registered June 14, 2017.

Use of an Automated Surgical Impactor Reduces Femoral Broaching Time in Direct Anterior Approach Total Hip Arthroplasty: Results From a Randomized, Multicenter Study.

Background: Impaction in total hip arthroplasty has typically been conducted using a mallet. A surgical automated impactor has been developed with the goal of reducing surgeon variability, fatigue, and injury. There is also potential to reduce the variability of each impaction step in which automated impaction is used, through reproducible and consistent application of force. Methods: Patients were randomized into either the mallet control group, or the automated impaction study group (1:1 randomization). The primary endpoint analysis was conducted to demonstrate that femoral broaching time (in minutes) with an automated impactor is noninferior to femoral broaching time with manual instruments (mallet) under a noninferiority (NI) margin of 1.25 minutes, with a subsequent test of superiority. A total of 218 patients were randomized and treated (109 in each group). Results: Mean femoral broaching time was 5.8 minutes in the automated impaction study group (automated), and 8.1 minutes in the mallet control group (mallet), a 28.4% reduction (P = .0005). However, there was not a difference in surgery duration between the groups. Three fractures were reported in the mallet group and 1 in the automated group. Conclusions: In this randomized multicenter study, an automated impactor was shown to reduce femoral broaching time in primary total hip arthroplasty, with no increase in fractures, but no decrease in operating room time was noted.

Five-Year Survivorship of Total Hip Arthroplasty With a Proximally Coated, Medially Collared, Triple-Tapered Femoral Stem: A Retrospective, Multicenter Registry Review.

Background The anterior approach for total hip arthroplasty (THA) has gained popularity in recent years. Some surgeons have been hesitant to adopt the approach due to concerns over increased complications such as intraoperative fracture, stem loosening, and stem revision. This study aims to evaluate the all-cause revision rate and survivorship of a collared, triple-tapered stem that was designed specifically for use with the anterior approach in THA to enhance outcomes and reduce adverse events. Methodology A retrospective outcomes review was conducted to assess survivorship and clinical outcomes for a specific proximally coated, medially collared triple-tapered (MCTT) femoral stem. Results In a cohort of 5,264 hips, Kaplan-Meier survivorship estimates (95% confidence interval [CI]; N with further follow-up), with survivorship defined as no revision of any component for any reason at five years after the index procedure, were 98.9% (97.8%-99.4%; 43) under the clinical assumption and 99.6% (99.4%-99.7%; 894) under the registry assumption. With survivorship defined as stem revision for any reason, survivorship estimates at five years postoperatively were 99.6% (99.3%-99.8%; 43) under the clinical assumption and 99.8% (99.7%-99.9%; 894) under the registry assumption. The mean follow-up time was 94.52 days (standard deviation [SD] 2.24, range 90.03-96.02). At five years postoperatively, the mean Harris Hip Score was 95.19, and the mean Hip Disability and Osteoarthritis Outcome Score Junior (HOOS JR) score was 98.66. Conclusions Our evaluation demonstrates excellent construct and stem survivorship and very low complication rates at midterm postoperative follow-up.

Intermediate-Term Survivorship of Total Hip Arthroplasty With a Proximally Coated Tapered-Wedge Femoral Stem: A Retrospective, Multi-Center Registry Review.

BACKGROUND: Short tapered-wedge stems have been used frequently over the past decade, but long-term follow-up data are not readily available in the literature. METHODS: A retrospective outcomes review was conducted to assess survivorship and clinical outcomes for the TRI-LOCK® Bone Preservation Stem (TRI-LOCK BPS; DePuy Synthes, Warsaw, IN, USA), a proximally coated, tapered-wedge femoral stem. RESULTS: In a cohort of 2,040 hips, Kaplan-Meier survivorship estimates (95% CI {confidence interval}; N with further follow-up, where N is the number of hips remaining at each post-operative interval), with survivorship defined as no revision of any component for any reason were 96.6% (92.8%,98.4%; 45) at eight years under the clinical assumption and 98.6% (97.9%,99.1%; 90) at 14 years under the registry assumption. With survivorship defined as stem revision for any reason, estimates were 97.7% (93.7%,99.2%; 45) at eight years under the clinical assumption and 99.2% (98.6%,99.5%; 90) under the registry assumption. Mean Harris Hip Scores and WOMAC scores were 90.08 and 21.98, respectively, at 10 years postoperatively. CONCLUSION: Our evaluation demonstrates excellent construct and stem survivorship and clinical outcomes at intermediate-term postoperative follow-up.

Mitigating calcar fracture risk with automated impaction during total hip arthroplasty.

Background: Automated broaching has recently been introduced for total hip arthroplasty (THA), with the goal of improving surgical efficiency and reducing surgeon workload. While studies have suggested that this technique may improve femoral sizing and alignment, little has been published regarding its safety, particularly with regard to calcar fractures. The purpose of our study was to evaluate the risk of calcar fracture during automated broaching, and to determine if this risk can be mitigated. Methods: We queried our prospective institutional database and identified 1596 unilateral THAs performed by the senior author using automated impaction between 2019 and 2023. We identified the incidence of calcar fracture with automated impaction, and whether the fracture occurred during broaching or stem insertion. We additionally determined calcar fracture incidence within two consecutive subgroups of patients using different stem insertion techniques; subgroup (1): automated broaching with automated stem insertion for all patients; versus subgroup (2): automated broaching with automated stem insertion ONLY if a cushion of cancellous bone separated the broach from the calcar, otherwise the stem was placed manually. Continuous and categorical variables were analyzed with Student's t-test and Fisher's exact test, respectively. Results: Seventeen calcar fractures occurred intraoperatively (1.1 %). Only two fractures occurred during automated broaching (0.1 %), while fifteen occurred during final stem impaction (0.9 %) (p = 0.007). Four calcar fractures (1.4 %) occurred in subgroup 1, compared to two in subgroup 2 (0.6 %) (p = 0.28). Conclusions: Our study found a calcar fracture incidence of 1.1 % using automated impaction, consistent with historically reported rates of 0.4-3.7 %. We found that calcar fractures are more likely to occur during stem insertion than during femoral broaching. We recommend that if any part of the final broach is in direct contact with the calcar, the final stem should be impacted manually to minimize fracture risk.