No Revisions Attributable To Wear of Highly Cross-Linked Polyethylene Liners: A Long Term Follow-up Study.

INTRODUCTION: There is a paucity of data beyond 15 years on the survivorship of total hip arthroplasty since the introduction of highly cross-linked polyethylene (HXLPE) liners. Our aim was to evaluate implant survivorship, liner wear rates, and clinical outcomes after primary THA using HXLPE liners implanted between 1999 and 2002. METHODS: Between 1999 and 2002, 690 primary THAs utilizing 28-mm femoral heads and HXLPE liners of a single design were identified using our institutional total joint registry. Femoral heads were made of metal in 96% of cases and ceramic in 4%. The mean age was 56 years, 48% were women, and the mean BMI was 30. Survivorship analyses were performed for the outcomes of implant revision, reoperation, and complications for the entire cohort. Linear HXLPE liner wear rates were determined on 197 hips with radiographs with more than 18.5 years of follow-up. RESULTS: At 20 years, survivorship free of revision was 94%, free of reoperation was 92%, and free of any complication was 81%. There were no documented wear-related revisions. The linear wear rate at a mean of 20.3 years postoperatively was 0.02 mm/year. There was no statistically significant difference in measured wear observed between the first available postoperative radiographs and those taken at the final follow-up. The use of elevated liners, patient BMI, age, preoperative diagnosis, acetabular component inclination, and anteversion angles were not associated with increased wear rates. Mean Harris Hip Scores improved from 52 preoperatively to 90 at greater than 18.5 years. CONCLUSIONS: Primary THAs using a single first generation HXLPE liner demonstrated excellent survivorship and clinical outcomes at long-term follow-up with no wear-related revisions. Wear rates of HXLPE liners at 20 years are exceedingly low and are not significantly impacted by acetabular component position or patient-dependent variables such as BMI. LEVEL OF EVIDENCE: IV.

Identifying Critical Evidence Gaps in Wound Closure and Incision Management After Total Knee Arthroplasty: Delphi Panel Insights.

INTRODUCTION: In orthopaedic surgery, particularly total knee arthroplasty (TKA), the management of surgical wounds is critical for optimal wound healing and successful patient outcomes. Despite advances in surgical techniques, challenges persist in effectively managing surgical wounds to prevent complications and infections. This study aimed to identify and address the critical evidence gaps in wound management in TKA, including preoperative optimization, intraoperative options, and for the avoidance of postoperative complications. These are important issues surrounding wound management, which is essential for improving patient recovery and the overall success of the surgery. METHODS: Utilizing the Delphi method, this study brought together 20 experienced orthopaedic surgeons from Europe and North America. Conducted from April to September 2023, the process involved three stages: an initial electronic survey, a virtual meeting, and a concluding electronic survey. The panel reviewed and reached a consensus on 26 specific statements about wound management in TKA based on a comprehensive literature review. During these three stages and after further panel review, an alternative goal of the Delphi panel was to also identify critical evidence gaps in the current understanding of wound management practices for TKA. RESULTS: While the panel reached consensus on various wound management practices, they highlighted several major evidence gaps. Also, there was general consensus on issues such as wound closure methods including the use of mesh-adhesive dressings, skin glue, staples, sutures (including barbed sutures),and negative-pressure wound therapy (NPWT). However, it was deemed necessary that further evidence needs to be generated to address the cost-effectiveness of each and develop best practices for promoting patient outcomes. The identification of these gaps points to areas requiring more in-depth research and improvements to enhance wound care in TKA. DISCUSSION: The identification of these major evidence gaps underscores the need for targeted research in wound management surrounding TKA. Addressing these evidence gaps is crucial for the future development of more effective, efficient, and patient-friendly wound care strategies. Future research should prioritize these areas, focusing on comparative effectiveness studies and further developing clear guidelines for the use of emerging technologies. Bridging these gaps has the potential to improve patient outcomes, reduce complications, and elevate the overall success rate of TKA surgeries.

Total knee replacement with an accelerometer-based, hand-held navigation system improves knee alignment: reliable in all patients.

BACKGROUND: Achieving adequate alignment has traditionally been an important goal in total knee arthroplasty to achieve long-term implant survival. While accelerometer-based hand-held navigation systems (ABN) has been introduced as a way to achieve alignment, there is a limited body of evidence on its accuracy, especially in patients under 65 years with differing etiologies for knee arthritis. This study aimed to assess the precision of a specific ABN system in restoring the mechanical axis and report surgical variables and complications, with particular attention to younger patients. METHODS: We conducted a retrospective review of 310 primary TKA performed with ABN from May 2016 to February 2021. The mean patient age was 67.4 (SD 8.9) years, with 43% under 65 years and mean body mass index of 33.2 (SD 6.8). The average surgical time was 96.8 min (57-171) and the average follow-up was 3.3 years (1.9-6.7). Data regarding length of stay, pain, range of motion (ROM), complications, and reinterventions were collected from the institutional joint arthroplasty registry and the medical records. Preoperative mechanical axis measurements and postoperative radiological data, including mechanical axis, component alignment and mechanical alignment outliers were analyzed. RESULTS: The mean preoperative mechanical axis was 175.4° (SD 7.6), with 248 knees (80%) in preoperative varus. The mean postoperative mechanical axis was 179.5° (SD 1.96) with 98% of knees falling within ± 3° of the neutral mechanical axis. Only 6 knees (2 varus, 4 valgus) fell outside the ± 3° range. And 3 knees (1 varus, 2 valgus) fell outside the ± 5° range. In the sagittal plane, 296 knees (95.5%) knees were within ± 3° of goal of 3 degrees of femoral flexion and 302 (97.4%) knees were within ± 2° of goal 1° of slope for tibial component. Far outliers (alignment outside ± 5° of targeted position) were found in 3 knees. Factors such as posttraumatic arthrosis, previous surgery, presence of retained hardware, and age below 65 years were not associated with increase in alignment outliers and far outliers. No complications related to the navigation system were observed. There were 22 complications and 20 reoperations, including 2 revisions for periprosthetic joint infection and 1 revision for flexion instability. Patients that required knee manipulation achieved an ultimate flexion of 110° (SD 14.1). CONCLUSIONS: The ABN system proved to be user-friendly and accurate in reducing alignment outliers in both coronal and sagittal planes in all patient populations. It offers a straightforward navigation solution while preserving surgeon autonomy and the use of traditional surgical tools. These findings advocate for the integration of this navigation system as a valuable tool to enhance the precision of TKA surgery in all patient groups.

Peri-Operative Management of Periacetabular Osteotomy: A Report of Current Practices from the Anchor Group, Supporting Literature, and Areas for Future Investigation.

Background: Periacetabular osteotomy (PAO) is a well-established surgical treatment for hip dysplasia, but very few studies report the impact of peri-operative management strategies on early pain and function. The purpose of this study is to describe peri-operative management variability among a group of experienced surgeons and review the literature supporting these practice patterns. Methods: We surveyed 16 surgeons that perform PAO to document various aspects of peri-operative management at four stages: pre-operative, intra-operative, post-operative in the hospital, and at discharge. Our goal was to report current surgical pain management strategies, adjunct medications, type of anesthesia, deep venous thrombosis and heterotopic ossification prophylaxis strategies, initiation of physical therapy, and use of continuous passive motion (CPM). We reviewed current literature to identify studies supporting these perioperative strategies and identify knowledge gaps that would benefit from further investigation. Results: Of the 16 surgeons surveyed, 75% had been in practice greater than 10 years and most had not altered their post-operative protocol for more than 3 years. 15/16 surgeons felt that length of stay could be reduced at their institution with improved peri-operative pain management. 6/16 were considering or had already implemented outpatient PAO as a part of their practice. We found significant variability in the pain medications provided at all peri-operative stages. 14/16 utilized general anesthesia, and many utilized epidural or peripheral nerve blocks. 6/16 surgeons utilized surgical field block (also referred to as periarticular block). These surgeons advocated that surgical field block was an effective intervention with no/minimal complication risk. There is very little literature critically evaluating efficacy of these perioperative management strategies for PAO. Conclusion: There is significant practice variability in peri-operative management of PAO surgery. We report various strategies utilized by a group of experienced surgeons and review supporting literature. There are significant knowledge gaps in best surgical pain management strategies, adjunct medications, surgical field blocks, and use of CPM that need further investigation. Level of Evidence: IV.

Total Hip Arthroplasty After Peri-Acetabular Osteotomy Results in Significant Improvement in Hip Function With Low Revision Rates at Mid-Term Follow-Up.

Background: Bernese periacetabular osteotomy (PAO) improves symptoms and delays degenerative changes in patients with acetabular dysplasia. Yet, eventual total hip arthroplasty (THA) is needed in many of these patients. The impact of PAO on subsequent THA outcomes is not well defined. The purpose of this study is to define: 1) clinical outcomes, 2) post-operative complications and 3) implant survivorship for patients undergoing THA after prior ipsilateral PAO. Methods: A retrospective review was conducted at three institutions to identify individuals undergoing THA after ipsilateral PAO surgery with minimum 1 year follow up. Patient reported outcome measures (PROMs) were collected preoperatively and at final follow-up. Surgical details, radiographic and clinical outcomes, and major complications according to the modified Dindo-Clavien classification system were identified through review of the medical record. Regression analysis and student's t-test were used to compare pre- and post-operative outcome scores. Kaplan-Meier analysis was performed to estimate reoperation-free survivorship. Results: A total of 113 THA in 112 patients were identified with initial review. 103 hips had a minimum of 1-year follow-up and an average follow of 5 ± 4 years (range, 1 to 20). 10 hips (9%) were lost to follow-up leaving 103 (91%) hips available for review with a minimum of 1-year follow-up (mean = 5 years). Mean interval from PAO to THA was 7.7 years (range, 2-15). The average post-operative mHHS improved 37 points (50 to 87, P < 0.001) when compared to pre-operative scores. Eight patients (7.1%) experienced a major grades III-V) surgical complication. These included 2 cases of instability, 2 cases of acetabular loosening, and one case each of periprosthetic fracture, wound dehiscence, periprosthetic infection, acetabular loosening and pneumonia. Failures occurred early at average 3.2 years and survivorship analysis for all-cause revision demonstrated 96% survivorship at both 5 and 10 years. Conclusion: THA after PAO achieves significant clinical improvement and satisfactory survivorship (96%) at mid-term follow-up, with a major complication rate of 7.1%. Level of Evidence: III.

Osteochondral Allograft Transplantation for the Treatment of an Acetabular Defect: A Case Report.

CASE: A 20-year-old woman presented with a unipolar, 1.8 × 1.8-cm osteochondral defect of the left acetabulum. Osteochondral allograft transplantation was performed using a medial tibial plateau allograft resulting in excellent clinical outcomes across 4 different outcome scores and maintenance of the joint space at 4.3 years postoperatively. CONCLUSION: Although previous literature has demonstrated long-term clinical success of osteochondral allograft transplantation in knee, excellent clinical outcomes can also be obtained in the hip. Thus, osteochondral allograft transplantation may be a viable treatment option for adolescents and young adults with concomitant cartilage and subchondral bone hip defects.

A Randomized Clinical Trial of Direct Anterior Versus Mini-Posterior Total Hip Arthroplasty: Small, Early Functional Differences Did Not Lead to Meaningful Clinical Differences at 7.5 Years.

BACKGROUND: Our previously reported randomized clinical trial of direct anterior approach (DAA) versus mini-posterior approach (MPA) total hip arthroplasty showed slightly faster initial recovery for patients who had a DAA and no differences in complications or clinical or radiographic outcomes beyond 8 weeks. The aims of the current study were to determine if early advantages of DAA led to meaningful clinical differences beyond 5 years and to identify differences in midterm complications. METHODS: Of the 101 original patients, 93 were eligible for follow-up at a mean of 7.5 years (range, 2.1 to 10). Clinical outcomes were compared with Harris Hip, 12-Item Short Form Health Survey, and Hip Disability and Osteoarthritis Outcomes Scores (HOOS) scores and subscores, complications, reoperations, and revisions. RESULTS: Harris Hip scores were similar (95.3 ± 6.0 versus 93.5 ± 10.3 for DAA and MPA, respectively, P = .79). The 12-Item Short Form Health Survey physical and mental scores were similar (46.2 ± 9.3 versus 46.2 ± 10.6, P = .79, and 52.3 ± 7.1 versus 55.2 ± 4.5, P = .07 in the DAA and MPA groups, respectively). The HOOS scores were similar (97.4 ± 7.9 versus 96.3 ± 6.7 for DAA and MPA, respectively, P = .07). The HOOS quality of life subscores were 96.9 ± 10.8 versus 92.3 ± 16.0 for DAA and MPA, respectively (P = .046). No clinical outcome met the minimally clinically important difference. There were 4 surgical complications in the DAA group (1 femoral loosening requiring revision, 1 dislocation treated closed, and 2 wound dehiscences requiring debridement), and 6 surgical complications in the MPA group (3 dislocations, 2 treated closed, and 1 revised to dual mobility; 2 intraoperative fractures treated with a cable; and 1 wound dehiscence treated nonoperatively). CONCLUSIONS: At a mean of 7.5 years, this randomized clinical trial demonstrated no clinically meaningful differences in outcomes, complications, reoperations, or revisions between DAA and MPA total hip arthroplasty. LEVEL OF EVIDENCE: IV.

Diaphyseal Impaction Grafting Combined with Metaphyseal Cones: Outcomes in 88 Revision Total Knee Arthroplasties.

BACKGROUND: Metaphyseal cones with cemented stems can be successfully utilized in most revision total knee arthroplasties (TKAs). However, if the diaphysis has been previously violated, fixation of the cemented stem, which is important for cone ingrowth and construct survival, can be compromised. The initial results of our novel technique combining diaphyseal impaction bone-grafting with a metaphyseal cone were promising but required additional study. The purpose of the present study was to assess results of this technique in a larger cohort. METHODS: A metaphyseal cone combined with diaphyseal impaction grafting and a cemented stem was utilized in 88 revision TKAs at our institution, including 35 from our prior study. The mean age at the time of revision was 67 years, and 67% of patients were male. Patients had had a mean of 4 prior knee arthroplasty procedures. The 2 most common reasons for revision were aseptic loosening (78%) and 2-stage reimplantation for periprosthetic joint infection (PJI) (19%). The mean follow-up was 4 years. RESULTS: At the time of the latest follow-up, no cone-impaction grafting constructs required re-revision for aseptic loosening. Five-year survivorship free from any revision of the cone-impaction grafting construct and free from any reoperation was 95% and 65%, respectively. A total of 25 knees (28%) underwent reoperation, with the 2 most common indications being PJI and periprosthetic fracture. All cones were osseointegrated, and all bone graft appeared stable or incorporated. One patient had radiographic evidence of tibial component loosening despite a well-fixed cone; however, this patient was asymptomatic and had not undergone revision at 9 years. CONCLUSIONS: When presented with a sclerotic, polished diaphyseal canal with deficient cancellous bone and concomitant metaphyseal bone loss, our technique of combining diaphyseal impaction grafting with a metaphyseal cone proved extremely durable in this larger series of patients. No cone-impaction grafting constructs required re-revision for aseptic loosening. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Modular fluted tapered stems in two-stage reimplantation of previously infected total hip arthroplasties.

Aims: Uncemented implants are now commonly used at reimplantation of a two-stage revision total hip arthoplasty (THA) following periprosthetic joint infection (PJI). However, there is a paucity of data on the performance of the most commonly used uncemented femoral implants - modular fluted tapered (MFT) femoral components - in this setting. This study evaluated implant survival, radiological results, and clinical outcomes in a large cohort of reimplantation THAs using MFT components. Methods: We identified 236 reimplantation THAs from a single tertiary care academic institution from September 2000 to September 2020. Two designs of MFT femoral components were used as part of an established two-stage exchange protocol for the treatment of PJI. Mean age at reimplantation was 65 years (SD 11), mean BMI was 32 kg/m2 (SD 7), and 46% (n = 109) were female. Mean follow-up was seven years (SD 4). A competing risk model accounting for death was used. Results: The 15-year cumulative incidence of any revision was 24%. There were 48 revisions, with the most common reasons being dislocation (n = 25) and infection (n = 16). The 15-year cumulative incidence of any reoperation was 28%. Only 13 revisions involved the fluted tapered component (FTC), for a 15-year cumulative incidence of any FTC revision of 8%. Only two FTCs were revised for aseptic loosening, resulting in a 15-year cumulative incidence of FTC revision for aseptic loosening of 1%. Stem subsidence ≥ 5 mm occurred in 2% of unrevised cases. All stems were radiologically stable at most recent follow-up. Mean Harris Hip Score was 69 (SD 20) at most recent follow-up. Conclusion: This series demonstrated that MFT components were durable and reliable in the setting of two-stage reimplantation THA for infection. While the incidence of aseptic loosening was very low, the incidence of any revision was 24% at 15 years, primarily due to dislocation and recurrent PJI.

Incidence, treatment, and outcomes of modern dual-mobility intraprosthetic dissociations.

Aims: Dual-mobility (DM) components are increasingly used to prevent and treat dislocation after total hip arthroplasty (THA). Intraprosthetic dissociation (IPD) is a rare complication of DM that is believed to have decreased with contemporary implants. This study aimed to report incidence, treatment, and outcomes of contemporary DM IPD. Methods: A total of 1,453 DM components were implanted at a single academic institution between January 2010 and December 2021: 695 in primary and 758 in revision THA. Of these, 49 presented with a dislocation of the large DM head and five presented with an IPD. At the time of closed reduction of the large DM dislocation, six additional IPDs occurred. The mean age was 64 years (SD 9.6), 54.5% were female (n = 6), and mean follow-up was 4.2 years (SD 1.8). Of the 11 IPDs, seven had a history of instability, five had abductor insufficiency, four had prior lumbar fusion, and two were conversions for failed fracture management. Results: The incidence of IPD was 0.76%. Of the 11 IPDs, ten were missed either at presentation or after attempted reduction. All ten patients with a missed IPD were discharged with a presumed reduction. The mean time from IPD to surgical treatment was three weeks (0 to 23). One patient died after IPD prior to revision. Of the ten remaining hips with IPD, the DM head was exchanged in two, four underwent acetabular revision with DM exchange, and four were revised to a constrained liner. Of these, five (50%) underwent reoperation at a mean 1.8 years (SD 0.73), including one additional acetabular revision. No patients who underwent initial acetabular revision for IPD treatment required subsequent reoperation. Conclusion: The overall rate of IPD was low at 0.76%. It is essential to identify an IPD on radiographs as the majority were missed at presentation or after iatrogenic dissociation. Surgeons should consider acetabular revision for IPD to allow conversion to a larger DM head, and take care to remove impinging structures that may increase the risk of subsequent failure.

Highly Porous Acetabular Cup and Augment Constructs in Complex Revision Total Hip Arthroplasty: What Predicts 10-Year Implant Survivorship?

BACKGROUND: Porous tantalum acetabular cup and augment constructs have demonstrated favorable outcomes up to 5 years postsurgery despite severe bone loss during revision total hip arthroplasty (THA). Prior literature lacks long-term studies with substantial case numbers. This study aims to assess long-term clinical and radiographic outcomes 10 years postsurgery in patients undergoing revision THA with porous tantalum acetabular cup-augment constructs and determine factors associated with long-term survivorship. METHODS: Between 2000 and 2012, 157 revision THAs were performed in cases with major acetabular defects (mainly Paprosky type IIIA and IIIB) utilizing porous tantalum cup-augment constructs. Pelvic discontinuity was noted intraoperatively in 17 hips (11%). Postoperative radiographs were evaluated at regular intervals for implant stability and radiolucent lines. There were 49 patients who had complete radiographic follow-up at 10 years or longer postsurgery. RESULTS: The 10-year survivorship free of revision of the cup-augment construct for aseptic loosening was 93%, free of any acetabular construct revision was 91%, free of any hip rerevision was 77%, and free of any reoperation was 75%. Pelvic discontinuity was associated with increased risk of reoperation (hazard ratio [HR] = 2.8), any hip rerevision (HR = 3.2), any cup-augment construct revision (HR = 11.8), and aseptic construct revision (HR = 10.0). Of unrevised cases with radiographs at 10 years, 4 hips showed radiographic loosening. Mean Harris hip scores improved from 47 preoperatively to 79 at 10 years. CONCLUSIONS: Porous tantalum acetabular cup-augment constructs used in revision THA with severe acetabular bone loss provide excellent implant survivorship at 10 years when the acetabulum is intact. Due to lower survivorship of cup-augment constructs in cases of pelvic discontinuity, additional construct fixation or stabilization methods are recommended, when a discontinuity is present. LEVEL OF EVIDENCE: IV.

Contemporary Aseptic Revision Total Hip Arthroplasty in Patients ≤50 Years of Age: Results of >500 Cases.

BACKGROUND: There has been a paucity of long-term outcomes data on aseptic revision total hip arthroplasties (THAs) in the young adult population. The purpose of this study was to evaluate implant survivorship, complications, and clinical outcomes in a large cohort of contemporary aseptic revision THAs in patients ≤50 years of age at the time of the surgical procedure. METHODS: We identified 545 aseptic revision THAs performed at a single academic institution from 2000 to 2020 in patients who were 18 to 50 years of age. Patients who underwent conversion THAs and patients with a history of any ipsilateral hip infection were excluded. The mean age was 43 years, the mean body mass index (BMI) was 29 kg/m 2 , and 63% were female. The index indication for revision THA was aseptic loosening in 46% of cases, polyethylene wear or osteolysis in 28% of cases (all revisions of conventional polyethylene), and dislocation in 11% of cases. There were 126 hips (23%) that had undergone at least 1 previous revision (median, 1 revision [range, 1 to 5 revisions]). The mean follow-up was 10 years. RESULTS: In the entire cohort, the 20-year survivorship free of any re-revision was 76% (95% confidence interval [95% CI], 69% to 82%). There were 87 re-revisions, with 31 dislocations, 18 cases of aseptic loosening of the femoral component, and 16 periprosthetic joint infections (PJIs) being the most common reasons for re-revision. Dislocation as the indication for the index revision was associated with an increased risk of re-revision (hazard ratio, 2.9; p < 0.001). The 20-year survivorship free of any reoperation was 73% (95% CI, 66% to 78%). There were 75 nonoperative complications (14%), including 32 dislocations. The mean Harris hip score significantly improved (p < 0.001) from 65 preoperatively to 81 at 10 years postoperatively. CONCLUSIONS: Contemporary aseptic revision THAs in patients ≤50 years of age demonstrated a re-revision risk of approximately 1 in 4 at 20 years. Dislocation, aseptic loosening of the femoral component, and PJI were the most common reasons for re-revision. Index revision THAs for dislocation had a 3 times higher risk of re-revision. LEVEL OF EVIDENCE: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

The Femur-First Technique for Oxford Medial Unicompartmental Knee Arthroplasty.

Background: Unicompartmental knee arthroplasty (UKA) is a reliable procedure to treat medial compartment knee osteoarthritis (OA). The reported survivorship of UKA has varied in the literature3-7. In part, the higher failure rates of UKA seen in registries could be related to the caseload and experience of the reporting surgeon8. The introduction of techniques that make procedures more reliable, especially in the hands of inexperienced surgeons, can decrease the rate of failure. With the Oxford UKA implant (Zimmer Biomet), the recommended surgical technique involves cutting the tibia first, followed by the femoral preparation. However, a technique that allows for preparation of the femur first, as well as the use of the femoral component as a reference for the tibial cut, may reduce the common technical errors seen with the procedure. We have utilized the femur-first technique in cases of medial Oxford UKA. Description: The femur-first method outlined in the present article does not require any unique instruments beyond what is supplied by the manufacturer. Before beginning, the femoral positional guide needs to be decoupled from its base. To start, the intramedullary guide is introduced approximately 1 cm anterior and medial to the intercondylar notch. Once the femoral osteophytes are removed, the surgeon identifies the center of the femoral condyle and marks it. The posterior tibial cartilage is then removed with a saw to facilitate the placement of the appropriately sized femoral spherical guide. The size of the femoral component is determined by selecting the implant that aligns best with the width of the femoral condyle. The femoral drill guide is detached from its base because there is not enough space for the base, as the tibia has not yet been resected. The decoupled femoral guide is connected to the intramedullary rod, allowing the precise positioning of the femoral component in approximately 10° of flexion relative to the femoral sagittal plane and drilling of the 2 peg holes. The posterior condylar resection guide is impacted into position, and the osteotomy of the posterior condyle is made. The distal femur is then milled with use of a number-0 spigot, and the femoral component trial is positioned into place. The femoral condyle is "resurfaced" with the femoral component, which restores joint obliquity and the natural height, a critical element of the femur-first technique. Following this, the 1-mm (size-dependent) spherical gauge is placed around the femoral component trial. The tibial guide is secured with the G-clamp and a number-0 resection block, and is pinned into place. We recommend swapping the number-0 cutting guide for a +2 when making the cut in order to avoid over-resection. Recutting is advised if a minimum 3-mm feeler gauge does not adequately occupy the flexion space. The final step is to balance the flexion and extension gaps in the usual fashion. Alternatives: The alternative technique is a traditional tibia-first approach, in which tibial resection is performed prior to femoral resection. As described in the original manufacturer's manual, the tibial cut is accomplished with use of a number-0 cutting guide, and the tibial rotation is based on the axis formed by the anterior superior iliac spine and knee center, irrespective of the femoral condyle. Rationale: The femur-first technique is advantageous in several ways. When performing the femoral cut first, the surgeon can better align the drill guide at the center of medial femoral condyle. This will result in the femoral component being positioned more in line with the coronal plane of the femoral condyle. Additionally, the tibial resection is made with the femoral trial in place; therefore, the depth of resection can be more accurate, potentially avoiding excessive bone resection. Finally, with the femoral trial in place, the surgeon can judge the rotation and medial-lateral position of the tibial component more precisely, hence lowering the possibility of bearing spin-out, impingement, and dislocation or unexplained pain. Expected Outcomes: The femur-first technique is a bone-preserving procedure that results in thinner bearings when compared with a tibia-first approach1. The femur-first approach also improves radiographic outcomes, including femoral coronal, femoral sagittal, and tibial sagittal alignments, while tibial coronal alignment does not differ. There is an early trend toward improved 5-year survivorship with the femur-first (98%) versus tibia-first (94%, p = 0.35) techniques. There has been no significant difference reported in Knee Society Scores between techniques. Important Tips: Perform a preliminary cut of the posterior tibial cartilage in order to allow insertion of the femoral drill guide under the femoral condyle.Make sure the femoral drill guide lies in the center of the marked medial femoral condyle.Align the tibial sagittal cut with the femoral component trial in order to avoid bearing impingement.Be conservative in the tibial cutting by utilizing a +2 cutting guide (since the coupling is performed with the intramedullary guide in place, which drives the tibial guide distally). Acronyms and Abbreviations: UKA = unicompartmental knee arthroplastyFF = femur-firstM-L = medial-lateralAP = anteroposteriorPA = posteroanteriorASA = acetylsalicylic acid (aspirin)BID = bis in die, twice a dayPT = physical therapyTF = tibia-firstFCA = femoral coronal angleFSA = femoral sagittal angleTSA = tibial sagittal angleIM = intramedullaryOA = osteoarthritis.

Femoral Coronal Malalignment is Associated With Failure in Mobile-Bearing Medial Unicompartmental Knee Arthroplasty.

BACKGROUND: Femur-first (FF) technique for mobile-bearing medial unicompartmental knee arthroplasty (UKA) has been described as an alternative to tibia-first (TF) technique. The aim of this study was to compare the radiographic results in UKAs using FF or TF techniques and their influence on failure rates. METHODS: We retrospectively reviewed 288 UKAs with a minimum 2-year follow-up. There were 147 knees in the TF and 141 knees in the FF cohorts. Alignment parameters and overhang were assessed as outliers and far outliers. The mean follow-up was 6 years (range, 2 to 16), the mean age was 63 years (range, 27 to 92), and 45% of patients were women. Univariate and multivariate statistical analyses were carried out with Cox regression models. RESULTS: There were 13 and 6 revisions in the TF and FF cohorts, respectively. The FF had lower rates of femoral coronal alignment (FCA) or femoral sagittal alignment outliers compared to the TF (5.7% versus 19%, P = .011). Tibial coronal alignment and tibial sagittal alignment did not significantly differ between the techniques (22.7% in FF versus 29.9% in TF, P = .119). Overhang outliers did not differ significantly between the groups. Younger age was associated with a higher revision rate (P = .006), while FF versus TF, sex, body mass index, and postoperative mechanical axis did not show statistically significant associations. In multivariate analysis, FCA outliers and younger age were significantly associated with revision. CONCLUSIONS: The FF technique in mobile-bearing UKA resulted in fewer FCA outliers compared to TF. Despite improved knee alignment with the FF technique, FCA outliers and younger age were associated with a higher revision rate, independent of technique.

The Frank Stinchfield Award: Assembly and Dissociation Forces Differ Between Commonly Used Dual Mobility Implants: A Biomechanical Study.

BACKGROUND: Intraprosthetic dissociation (IPD) is a complication unique to dual mobility (DM) implants where the outer polyethylene head dissociates from the inner femoral head. Increasing reports of IPD at the time of closed reduction of large head DM dislocations prompted this biomechanical study evaluating the assembly and dissociation forces of DM heads. METHODS: We tested 17 polyethylene DM heads from 5 vendors. Of the heads, 12 were highly cross-linked polyethylene (4 vendors) and 5 were infused with vitamin E (2 vendors). Heads were between 46 and 47 mm in diameter, accepting a 28 mm-inner ceramic head. Implants were assembled and disassembled using a servohydraulic machine that recorded the forces and torques applied during testing. Dissociation was tested via both axial pull-out and lever-out techniques, where lever-out simulated stem-on-acetabular component impingement. RESULTS: The initial maximum assembly force was significantly different between all vendors (P < .01) and decreased for all implants with subsequent assembly. Vendor 4-E (Link with vitamin E) heads required the highest assembly force (1,831.9 ± 81.95 N), followed by Vendor 3 (Smith & Nephew), Vendor 5 (DePuy Synthes), Vendor 1-E (Zimmer Biomet with vitamin E), Vendor 2 (Stryker), and Vendor 1 (Zimmer Biomet Arcom). Vendor 4-E implants showed the greatest dissociation resistance in both pull-out (2,059.89 N, n = 1) and lever-out (38.95 ± 2.79 Nm) tests. Vendor 1-E implants with vitamin E required higher assembly force, dissociation force, and energy than Vendor 1 heads without vitamin E. CONCLUSIONS: There were notable differences in DM assembly and dissociation forces between implants. Diminishing force was required for assembly with each additional trial across vendors. Vendor 4-E DM heads required the highest assembly and dissociation forces. Vitamin E appeared to increase the assembly and dissociation forces. Based on these results, DM polyethylene heads should not be reimplanted after dissociation, and there may be a role for establishing a minimum dissociation energy standard to minimize IPD risk.

International Delphi Study on Wound Closure and Incision Management in Joint Arthroplasty Part 2: Total Hip Arthroplasty.

BACKGROUND: This modified Delphi study aimed to develop a consensus on optimal wound closure and incision management strategies for total hip arthroplasty (THA). Given the critical nature of wound care and incision management in influencing patient outcomes, this study sought to synthesize evidence-based best practices for wound care in THA procedures. METHODS: An international panel of 20 orthopedic surgeons from Europe, Canada, and the United States evaluated a targeted literature review of 18 statements (14 specific to THA and 4 related to both THA and total knee arthroplasty). There were 3 rounds of anonymous voting per topic using a modified 5-point Likert scale with a predetermined consensus threshold of ≥ 75% agreement necessary for a statement to be accepted. RESULTS: After 3 rounds of voting, consensus was achieved for all 18 statements. Notable recommendations for THA wound management included (1) the use of barbed sutures over non-barbed sutures (shorter closing times and overall cost savings); (2) the use of subcuticular sutures over skin staples (lower risk of superficial infections and higher patient preferences, but longer closing times); (3) the use of mesh-adhesives over silver-impregnated dressings (lower rate of wound complications); (4) for at-risk patients, the use of negative pressure wound therapy over other dressings (lower wound complications and reoperations, as well as fewer dressing changes); and (5) the use of triclosan-coated sutures (lower risk of surgical site infection) over standard sutures. CONCLUSIONS: Through a structured modified Delphi approach, a panel of 20 orthopedic surgeons reached consensus on all 18 statements pertaining to wound closure and incision management in THA. This study provides a foundational framework for establishing evidence-based best practices, aiming to reduce variability in patient outcomes and to enhance the overall quality of care in THA procedures.

Primary Hip Arthroscopy in Patients With Acetabular Dysplasia: A Systematic Review of Published Clinical Outcomes at Minimum 5-Year Follow-up.

BACKGROUND: Hip arthroscopy in patients with borderline hip dysplasia has satisfactory outcomes at short-term follow-up; however, the data on midterm outcomes are inconsistent, and failure rates are high in some studies, limiting understanding of the role and utility of hip arthroscopy in this patient cohort. PURPOSE: To provide an up-to-date, evidence-based review of the clinical outcomes of primary hip arthroscopy in patients with frank or borderline hip dysplasia at ≥5-year follow-up and report the failure rate and progression to total hip arthroplasty in this cohort. STUDY DESIGN: Systematic review; Level of evidence, 4. METHODS: A comprehensive literature search was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Studies were included if they evaluated outcomes of primary hip arthroscopy in patients with lateral center-edge angle (LCEA) <25° at ≥5-year follow-up. Risk of bias assessment was performed using the methodological index for non-randomized studies scoring system. Level of evidence was determined using criteria from the Oxford Centre for Evidence-Based Medicine. RESULTS: Nine studies were included in this review. Patients with LCEA <25° demonstrated satisfactory clinical outcomes, high patient satisfaction, and significant postoperative improvements in patient-reported outcomes (PROs) at follow-up ranging from a ≥5 to 10 years. Studies comparing patients with dysplasia to those without did not demonstrate significant differences in preoperative, postoperative, or delta PROs or in failure, reoperation, or revision rates. There was no overall significant correlation between outcomes and LCEA stratification. CONCLUSION: Hip arthroscopy in carefully selected patients with LCEA <25° can be successful at mid- to long-term follow-up and may provide clinical outcomes and failure rates comparable with patients with normal LCEA, understanding that this is a singular, 2-dimensional radiographic measure that does not differentiate instability from impingement or combinations thereof, warranting future studies delineating these differences. These findings suggest that hip dysplasia may not be an absolute contraindication for isolated hip arthroscopy and may serve as a viable intervention with consideration of staged future periacetabular osteotomy (PAO). Importantly, this review does not suggest that hip arthroscopy alters the natural history of dysplasia; therefore, patients with dysplasia should be counseled on the potential utility of PAO by appropriate hip preservation specialists.

A New Arthroscopic Classification for Chondrolabral Disease in Patients Undergoing Surgery for Developmental Dysplasia of the Hip.

BACKGROUND: Current classification systems for intra-articular pathology intraoperatively have been described for patients with femoroacetabular impingement rather than dysplasia. PURPOSE: To (1) describe intra-articular findings in dysplastic hips undergoing combined hip arthroscopy and periacetabular osteotomy (PAO); (2) propose a new chondrolabral classification system for dysplastic hips based on these findings; and (3) correlate patient-reported outcome measures (PROM) with the newly proposed classification. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A total of 46 hips underwent combined hip arthroscopy and PAO at our institution between September 2013 and December 2014, irrespective of symptoms or radiographic findings. PROMs were evaluated preoperatively and at 2 years postoperatively. At the time of hip arthroscopy, the chondrolabral junction was classified as normal without tear (1 hip, type 1); hypertrophic labrum without chondrolabral disruption (19 hips, type 2); chondrolabral disruption on the articular side, not extending into the capsular side (16 hips, type 3A); chondrolabral disruption extending through the capsular side (3 hips, type 3B); and exposed acetabular subchondral bone (7 hips, type 4). RESULTS: There was a significant difference in postoperative modified Harris Hip Score (mHHS) (P = .020), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain scores (P = .037), and WOMAC total scores (P = .049) between chondrolabral junction types. Post hoc analyses demonstrated significant differences between type 2 (84.9 ± 12.9) and type 3A (67.8 ± 20.7; P = .198), and between type 2 and type 4 (59.3 ± 24.3; P = .011) in postoperative mHHS scores; and between type 2 (83.9 ± 12.9) and type 3A (68.9 ± 23.7; P = .045) in postoperative WOMAC total scores. In multivariate analysis, chondrolabral type 3 or type 4, age >35 years, and previous surgery were significantly correlated with worse mHHS scores at 2 years. CONCLUSION: This new chondrolabral classification is proposed to describe intra-articular pathology seen during combined hip arthroscopy and PAO, specifically in dysplastic hips. More advanced chondrolabral disease was associated with worse PROMs at 2 years.

International Delphi Study on Wound Closure and Dressing Management in Joint Arthroplasty: Part 1: Total Knee Arthroplasty.

BACKGROUND: The purpose of this modified Delphi study was to obtain consensus on wound closure and dressing management in total knee arthroplasty (TKA). METHODS: The Delphi panel included 20 orthopaedic surgeons from Europe and North America. There were 26 statements identified using a targeted literature review. Consensus was developed for the statements with up to three rounds of anonymous voting per topic. Panelists ranked their agreement with each statement on a five-point Likert scale. An a priori threshold of ≥ 75% was required for consensus. RESULTS: All 26 statements achieved consensus after three rounds of anonymous voting. Wound closure-related interventions that were recommended for use in TKA included: 1) closing in semi-flexion versus extension (superior range of motion); 2) using aspirin for venous thromboembolism prophylaxis over other agents (reduces wound complications); 3) barbed sutures over non-barbed sutures (lower wound complications, better cosmetic appearances, shorter closing times, and overall cost savings); 4) mesh-adhesives over other skin closure methods (lower wound complications, higher patient satisfaction scores, lower rates of readmission); 5) silver-impregnated dressings over standard dressings (lower wound complications, decreased infections, fewer dressing changes); 6) in high-risk patients, negative pressure wound therapy over other dressings (lower wound complications, decreased reoperations, fewer dressing changes); and 7) using triclosan-coated over non-antimicrobial-coated sutures (lower risks of surgical site infection). CONCLUSIONS: Using a modified Delphi approach, the panel achieved consensus on 26 statements pertaining to wound closure and dressing management in TKA. This study forms the basis for identifying critical evidence supported by clinical practice for wound management to help reduce variability, advance standardization, and ultimately improve outcomes during TKA. The results presented here can serve as the foundation for knowledge, education, and improved clinical outcomes for surgeons performing TKAs.