Highly Cross-Linked Polyethylene in Patients 50 Years of Age and Younger: A 20-year Follow-Up Analysis.

BACKGROUND: Highly cross-linked polyethylene (HXLPE) has been an excellent bearing for total hip arthroplasty (THA) due to improved wear characteristics compared to conventional materials. Patients 50 years of age or younger are at high risk for wear-related complications of their THA, and few studies have followed these patients who have HXPLE into the third decade. METHODS: In a retrospective review of 88 consecutive THAs performed in 77 patients aged 50 years and younger (mean 41; range, 20 to 50), in which HXLPE was utilized, they were evaluated for their clinical and radiographic results at an average of 20-year follow-up (range, 18 to 24). The current study reports on longer-term follow-up from our previously published series at shorter follow-up times. Patients were categorized by femoral head material: cobalt chrome (n = 14), ceramic (n = 30), and oxidized zirconium (n = 22) and by femoral head size: 26 mm (n = 12), 28 mm (n = 46), and 32 mm (n = 8). Harris Hip Scores were collected preoperatively and at the most recent follow-up. Radiographs were evaluated for linear and volumetric wear, radiolucent lines, and osteolysis. RESULTS: Mean Harris Hip Scores improved from 47.1 (standard deviation [SD] 8.8) preoperatively to 92.0 (SD 7.7) (P < .0001) at 20-year follow-up. There was one hip that was revised for recurrent instability, and no hip demonstrated radiographic evidence of loosening or osteolysis. The mean polyethylene linear wear rate was 0.017 (SD 0.012) mm/y, and the mean polyethylene volumetric wear rate was 3.15 (SD 2.8) mm3/year, with no significant differences based on articulation type or head size. CONCLUSIONS: Total hip arthroplasty with HXLPE in patients ≤ 50 years of age continues to demonstrate excellent long-term clinical and radiographic outcomes with low wear characteristics at 20-year follow-up, regardless of femoral head material or size.

Metaphyseal Fixation Using Cones and Sleeves for Severe Proximal Tibial Bone Loss.

BACKGROUND: Tibial bone defects are commonly encountered in revision total knee arthroplasty (rTKA) and can be managed with metaphyseal cones or sleeves. Few studies have directly compared tibial cones and sleeves in rTKA, and none have limited this comparison to the most severe tibial defects. The purpose of this study was to evaluate and compare the outcomes of metaphyseal cones and sleeves for tibial reconstruction in rTKA regarding implant fixation and clinical outcomes. METHODS: A retrospective review was conducted on patients undergoing rTKA in which metaphyseal cones or sleeves were utilized for addressing metaphyseal bone loss (34 cones and 18 sleeves). Tibial bone loss was classified according to the Anderson Orthopaedic Research Institute bone defect classification, with types 2B and 3 being included. Patient-reported outcomes and postoperative complications were collected, and a radiographic evaluation of osseointegration or loosening was performed. RESULTS: There were 52 knees included (34 cones, 18 sleeves), with a median follow-up of 41.0 months. All-cause implant survival was 100% at 2 years and 96% (95% confidence interval: 76 to 99%) at 4 years, with 98% of tibial components demonstrating osseointegration at the final follow-up. During follow-up, there were a total 11 revisions, of which 1 sleeve was revised secondary to implant loosening. Tibial sleeves had a higher risk of revision compared to tibial cones (P < .01), and sleeves fixed with a hybrid technique were more likely to need revision than cones fixed by the same method (P = .01). CONCLUSIONS: Porous metaphyseal tibial cones and tibial metaphyseal sleeves both performed well at a 41-month median follow-up with no difference in aseptic survivorship between the 2 constructs. Both demonstrate high rates of osseointegration, low rates of aseptic failure, and significant improvement in Knee Society Scores in patients with severe tibial defects in rTKA.

Advancing Laryngeal Adductor Reflex Testing Beyond Sensory Threshold Detection.

Flexible endoscopic evaluation of swallowing with sensory testing (FEESST) is a promising clinical tool to assess airway integrity via the laryngeal adductor reflex (LAR). The current clinical protocol relies on sensory threshold detection, as relatively little is known about the motor response of this sensorimotor airway protective reflex. Here, we focused on characterizing normative LAR motion dynamics in 20 healthy young participants using our prototype high-pressure syringe-based air pulse device and analytic software (VFtrack™) that tracks vocal fold (VF) motion in endoscopic videos. Following device bench testing for air pulse stimulus characterization, we evoked and objectively quantified LAR motion dynamics in response to two suprathreshold air pulse stimuli (40 versus 60 mm Hg), delivered to the arytenoid mucosa through a bronchoscope working channel. The higher air pressures generated by our device permitted an approximate 1 cm endoscope working distance for continual visualization of the bilateral VFs throughout the LAR. Post hoc video analysis identified two main findings: (1) there are variant and invariant subcomponents of the LAR motor response, and (2) only a fraction of suprathreshold stimuli evoked complete glottic closure during the LAR. While the clinical relevance of these findings remains to be determined, we have nonetheless demonstrated untapped potential in the current FEESST protocol. Our ongoing efforts may reveal LAR biomarkers to quantify the severity of laryngeal pathology and change over time with natural disease progression, spontaneous recovery, or in response to intervention. The ultimate goal is to facilitate predictive modeling of patients at high risk for dysphagia-related aspiration pneumonia.

A Surgical Mouse Model for Advancing Laryngeal Nerve Regeneration Strategies.

Iatrogenic recurrent laryngeal nerve (RLN) injury is a morbid complication of anterior neck surgical procedures. Existing treatments are predominantly symptomatic, ranging from behavioral therapy to a variety of surgical approaches. Though laryngeal reinnervation strategies often provide muscle tone to the paralyzed vocal fold (VF), which may improve outcomes, there is no clinical intervention that reliably restores true physiologic VF movement. Moreover, existing interventions neglect the full cascade of molecular events that affect the entire neuromuscular pathway after RLN injury, including the intrinsic laryngeal muscles, synaptic connections within the central nervous system, and laryngeal nerve anastomoses. Systematic investigations of this pathway are essential to develop better RLN regenerative strategies. Our aim was to develop a translational mouse model for this purpose, which will permit longitudinal investigations of the pathophysiology of iatrogenic RLN injury and potential therapeutic interventions. C57BL/6J mice were divided into four surgical transection groups (unilateral RLN, n = 10; bilateral RLN, n = 2; unilateral SLN, n = 10; bilateral SLN, n = 10) and a sham surgical group (n = 10). Miniaturized transoral laryngoscopy was used to assess VF mobility over time, and swallowing was assessed using serial videofluoroscopy. Histological assays were conducted 3 months post-surgery for anatomical investigation of the larynx and laryngeal nerves. Eight additional mice underwent unilateral RLN crush injury, half of which received intraoperative vagal nerve stimulation (iVNS). These 8 mice underwent weekly transoral laryngoscopy to investigate VF recovery patterns. Unilateral RLN injury resulted in chronic VF immobility but only acute dysphagia. Bilateral RLN injury caused intraoperative asphyxiation and death. VF mobility was unaffected by SLN transection (unilateral or bilateral), and dysphagia (transient) was evident only after bilateral SLN transection. The sham surgery group retained normal VF mobility and swallow function. Mice that underwent RLN crush injury and iVNS treatment demonstrated accelerated and improved VF recovery. We successfully developed a mouse model of iatrogenic RLN injury with impaired VF mobility and swallowing function that can serve as a clinically relevant platform to develop translational neuroregenerative strategies for RLN injury.

Cementless Total Knee Arthroplasty: Is it Safe in Demineralized Bone?

There is concern for cementless total knee arthroplasty (TKA) in patients with decreased bone mineral density (BMD) due to the potential increase in complications, namely failed in-growth or future aseptic loosening. Some data suggest that advances in cementless prostheses mitigate these risks; however this is not yet born out in long-term registry data. It is crucial to expand our understanding of the prevalence and etiology of osteoporosis in TKA patients, survivorship of cementless implants in decreased BMD, role of bone-modifying agents, indications and technical considerations for cementless TKA in patients with decreased BMD. The purpose of this study is to review current literature and expert opinion on such topics.

Which Surgical Approach Provides Maximum Visualization and Access for Open Reduction and Internal Fixation of Femoral Head Fractures?

OBJECTIVES: Femoral head fracture open reduction and internal fixation (ORIF) requires adequate surgical access and visualization. The purpose of this study was to objectively characterize femoral head access associated with commonly used surgical approaches. Our hypothesis was that a surgical hip dislocation (SHD) provides the greatest visualization and access to the femoral head. METHODS: Ten fresh-frozen cadaveric whole-pelvis specimens (n = 20 hips) were used to compare 4 surgical approaches to the femoral head (n = 5 hips per approach): SHD, Smith-Petersen (with and without rectus release), and Hueter. After surgical exposure, standardized and calibrated digital images were captured and analyzed to determine the percent-area visualized. Three independent investigators assessed each specimen to determine surgical visualization and access to the following femoral head anatomic quadrants: anteromedial, anterolateral, posteromedial, and posterolateral. Data were analyzed for significant (P < 0.05) differences using analysis of variance (ANOVA) and Fisher exact tests. RESULTS: The Hueter approach provided the lowest calculated % visualization. For surgeon visualization, SHD demonstrated a significantly (P < 0.001) higher proportion of visualized anatomic landmarks compared with all other approaches. SHD provided significantly (P < 0.049) more access to the femoral head quadrants compared with all other approaches. The Hueter approach had significantly (P = 0.004) lower surgeon access compared with the Smith-Petersen with release. CONCLUSIONS: SHD provided superior visualization and access to clinically relevant femoral head anatomy compared with the Smith-Petersen with or without rectus release and Hueter approaches.

Which surgical approach provides maximum visualization and access for open reduction and internal fixation (ORIF) of femoral neck fractures?

OBJECTIVES: Appropriate visualization of the femoral neck is critical when performing open reduction and internal fixation (ORIF) of a femoral neck fracture. The purpose of this study was to objectively identify which surgical approach provided the most extensive visualization of the femoral neck during ORIF. Our hypothesis was that the Smith-Petersen approach with rectus release would provide the most extensive visualization. METHODS: Ten cadaveric hips were utilized to compare 4 different surgical approaches to the femoral neck: Smith-Petersen (SP), Smith-Petersen with rectus release (SPwR), Watson-Jones (WJ), and Hueter approach. After surgical exposure, calibrated digital images were captured and analyzed using a computer software program to determine the percent-area visualized. Three trained investigators separately assessed each specimen to determine clinical visualization and ability of the surgeon to manually outline anatomic locations of the femoral neck: subcapital, trans-cervical, and basicervical. Data were analyzed for significant (p < 0.05) differences using ANOVA and Fisher Exact tests. RESULTS: For calculated percent-visualization, SP and SPwR allowed for significantly more (p = 0.003) visualization than the Hueter and WJ approaches. For surgeon visualization, SP and SPwR were significantly higher (p < 0.029) when compared to WJ. The ability for the individual surgeon to outline the femoral neck's anatomical landmarks was significantly higher (p < 0.049) with SP and Hueter approaches compared with SPwR. CONCLUSION: The SP and SPwR provided superior visualization of femoral neck anatomy compared to Hueter and WJ approaches. Similarly, the SP approach allowed for optimal surgeon visualization of and access to clinically relevant femoral neck anatomic landmarks compared to other approaches assessed.

A prospective randomized double-blind clinical trial to assess the effects of leukocyte-reduced platelet-rich plasma on pro-inflammatory, degradative, and anabolic biomarkers after closed pilon fractures.

Posttraumatic osteoarthritis (PTOA) significantly affects patients with pilon fractures even after adequate anatomical reduction, and treatment strategies targeting the biologic mediators of PTOA are needed. This study was designed to determine the effects of intra-articular injection of platelet-rich plasma (PRP) on synovial fluid (SF) biomarkers for patients undergoing open reduction and internal fixation (ORIF) of pilon fractures. Patients undergoing staged management of pilon fractures were enrolled in a prospective, double-blinded, randomized, and placebo-controlled clinical trial to determine the effects of a single intra-articular injection of leukocyte-reduced PRP on SF biomarkers. Arthrocentesis of the injured and uninjured ankles was performed at the time of external skeletal fixation (ESF) and ORIF. Patients were randomized to receive either autogenous leukocyte-reduced PRP or saline (control) via intra-articular injection into the injured ankle at the time of ESF. SF biomarker concentrations were compared-uninjured, injured pretreatment, and saline-injected or PRP-injected. Eleven patients (PRP, n = 5; saline, n = 6) completed the study. Twenty-one uninjured, and 11 injured pretreatment, five PRP-treated, and six saline-treated SF samples were analyzed. PRP-treated SF contained significantly higher levels of PDGF-AA (p = 0.046) and significantly lower levels of MMP-3 (p = 0.042), MMP-9 (p = 0.009), IL-1ß (p = 0.049), IL-6 (p < 0.01), IL-8 (p = 0.048), and PGE2 (p < 0.04). This study provided mechanistic data to suggest that a single intraarticular injection of leukocyte-reduced PRP is associated with anti-inflammatory, anti-degradative, and anabolic responses compared with saline control. These findings provide the impetus for investigating long-term clinical outcomes after PRP injection as an orthobiologic adjunct to ORIF for mitigating the incidence and severity of PTOA after pilon fractures.

Revision Anterior Cruciate Ligament Reconstruction after Surgical Management of Multiligament Knee Injury.

The purpose of this study is to determine factors associated with the need for revision anterior cruciate ligament reconstruction (ACLR) after multiligament knee injury (MLKI) and to report outcomes for patients undergoing revision ACLR after MLKI. This involves a retrospective review of 231 MLKIs in 225 patients treated over a 12-year period, with institutional review board approval. Patients with two or more injured knee ligaments requiring surgical reconstruction, including the ACL, were included for analyses. Overall, 231 knees with MLKIs underwent ACLR, with 10% (n = 24) requiring revision ACLR. There were no significant differences in age, sex, tobacco use, diabetes, or body mass index between cohorts requiring or not requiring revision ACLR. However, patients requiring revision ACLR had significantly longer follow-up duration (55.1 vs. 37.4 months, p = 0.004), more ligament reconstructions/repairs (mean 3.0 vs. 1.7, p < 0.001), more nonligament surgeries (mean 2.2 vs. 0.7, p = 0.002), more total surgeries (mean 5.3 vs. 2.4, p < 0.001), and more graft reconstructions (mean 4.7 vs. 2.7, p < 0.001). Patients in both groups had similar return to work (p = 0.12) and activity (p = 0.91) levels at final follow-up. Patients who had revision ACLR took significantly longer to return to work at their highest level (18 vs. 12 months, p = 0.036), but similar time to return to their highest level of activity (p = 0.33). Range of motion (134 vs. 127 degrees, p = 0.14), pain severity (2.2 vs. 1.7, p = 0.24), and Lysholm's scores (86.3 vs. 90.0, p = 0.24) at final follow-up were similar between groups. Patients requiring revision ACLR in the setting of a MLKI had more overall concurrent surgeries and other ligament reconstructions, but had similar final outcome scores to those who did not require revision surgery. Revision ligament surgery can be associated with increased pain, stiffness, and decrease patient outcomes. Revision surgery is often necessary after multiligament knee reconstructions, but patients requiring ACLR in the setting of a MLKI have good overall outcomes, with patients requiring revision ACLR at a rate of 10%.

Patient-Reported Outcomes for Large Bipolar Osteochondral Allograft Transplantation in Combination with Realignment Osteotomies for the Knee.

Effective treatment for bipolar articular cartilage lesions in the knee remains a clinical challenge. Lower extremity malalignment is a risk factor for treatment failures, which can be addressed by tibial or femoral osteotomy. The purpose of this study was to compare outcomes among patients who underwent knee joint restoration by osteochondral allograft (OCA) transplantation with concurrent or staged realignment osteotomy. With Institutional Review Board approval, patients undergoing bipolar OCA transplantation with concurrent or staged distal femoral osteotomy (DFO) or high tibial osteotomy (HTO) were analyzed. Patients were categorized by osteotomy type (DFO and HTO) and timing (concurrent and staged). Patient-reported outcome measures (PROMs), revisions, failures, and complications were examined preoperatively (baseline), 3, 6, 12, and 24 months after OCA transplantation; change scores from preoperative values were used for analysis. A total of 23 patients met inclusion criteria (15 males); 13 (56.5%) received HTO (5 concurrent), while 10 (43.5%) received DFO (5 concurrent). There were no significant differences in complication rates between concurrent and staged osteotomies. Primary bipolar OCA transplantation with osteotomy was associated with successful outcomes in 70% of patients; four patients underwent revision (17.4%) and three (13.0%) failed and were treated by total knee arthroplasty. Further, the four patients undergoing revision met functional criteria for success at final follow-up, resulting in a 2-year functional survival rate of 87.4%. Aside from Patient-Reported Outcomes Measurement Information System (PROMIS) physical function, all PROMs for concurrent and staged osteotomies improved from baseline to 2 years postoperatively. Concurrent osteotomies of both types were associated with significantly lower pain scores at 12 months (p = 0.04), compared with staged osteotomies. Apart from Single Assessment Numerical Evaluation (SANE), more PROM improvement was observed for concurrent osteotomies at 2 years. Improvements in PROMs for patients undergoing OCA transplantation combined with osteotomy were observed at 2-year follow-up. PROMs for concurrent osteotomy were consistently greater than staged osteotomy, lending support to addressing lower extremity malalignment with bipolar OCA transplantation in the knee during a single surgery when possible.