A German-Wide Systematic Study on Mobilization and Collection of Hematopoietic Stem Cells in Poor Mobilizer Patients with Multiple Myeloma prior to Autologous Stem Cell Transplantation.

Introduction: In patients with a clinical indication for autologous hematopoietic stem cell transplantation (ASCT), sufficient mobilization of CD34+ precursor cells into peripheral blood is essential to ensure adequate hematopoietic stem cell (HSC) collection prior to intensive therapy. However, with standard granulocyte-colony stimulating factor (G-CSF)-based mobilization schemes, an important minority of patients fail to mobilize sufficient (e.g., >10/µL) CD34+ cell counts into the peripheral blood and are considered as poor mobilizers (PM). Because failure to achieve sufficient CD34+ cell mobilization can negatively affect important clinical treatment endpoints, the use of plerixafor (PLX) was approved to increase CD34+ mobilization in PM patients. Methods: The German non-interventional, multicenter, open-label, prospective OPTIMOB study evaluated HSC mobilization strategies prior to planned ASCT in adult patients with hematologic malignancies (lymphomas or multiple myeloma [MM]) focusing on PM patients. PM patients were defined as follows: (1) never achieving ≥20 CD34+ cells/µL before 1st apheresis, (2) receiving PLX at any timepoint of mobilization, (3) their initially planned stem cell yield had to be reduced, or (4) they had not received apheresis due to low CD34+ count in peripheral blood. Results: 168 of 475 MM patients (35%) participating in the OPTIMOB study were classified as PM, and 155 of them (92%) received PLX (PM+PLX) during the study. PM patients were 40-78 years old, slightly more often male (n = 97, 58%), mostly newly diagnosed (n = 146, 87%) and received highly individualized previous treatments. Ninety-four of the PMs underwent chemotherapy mobilization (65%), and 51 patients (35%) received steady-state mobilization with G-CSF only during 1st mobilization attempt. 92% of the total PM population (n = 155) underwent apheresis, 78% of them (n = 117) achieved >2.0 × 106 CD34+ cells/kg body weight on the 1st day of apheresis. PM+PLX had a higher median total collection result than those PM patients without PLX support (7.2 vs. 5.7 × 106 CD34+ cells/kg body weight). In total, ASCT was performed in 136 PM+PLX (88%) versus 8 PM-PLX patients (62%). Conclusion: The OPTIMOB study showed that a considerable proportion of adult MM patients in Germany are PMs. Even though most of PMs were supported with PLX in the OPTIMOB study, PM-PLX also successfully mobilized HSCs, allowing ASCT in majority of all PMs. However, further analyses are required for treatment optimization in PMs.

Mobilization and Hematopoietic Stem Cell Collection in Poor Mobilizing Patients with Lymphoma: Final Results of the German OPTIMOB Study.

Introduction: Successful mobilization and collection of peripheral hematopoietic stem cells (HSCs) are necessary for lymphoma patients eligible for myeloablative chemotherapy with subsequent autologous stem cell transplantation (ASCT). Albeit G-CSF alone or combined with chemotherapy is well-established methods for HSC mobilization, up to 40% of the patients fail to mobilize (poor mobilizer, PM). Plerixafor (PLX) is commonly used in PM patients resulting in increased migration of HSCs into peripheral blood and thus improves the collection outcome. Methods: The prospective, multicenter, open-label, non-interventional OPTIMOB study assessed mobilization and collection parameter of patients with lymphoma or multiple myeloma to get deep insights in the treatment of those patients in clinical routine focusing on PM patients. PM was defined as follows: (1) no achievement of ≥20 CD34+ progenitor cells/µL before first apheresis, (2) PLX administration at any time point during the observational period, (3) reduction of the initially planned CD34+ progenitor cell yield as necessity due to failed mobilization or HSC collection, and (4) no performance of apheresis due to low CD34+ progenitor level. Primary objective of the study was to assess mobilization success by the proportion of PM patients achieving >2 × 106 CD34+ progenitor cells/kg body weight on the first day of apheresis. Here, the data of the lymphoma cohort are presented. Results: Out of 238 patients with lymphoma documented in the study, 32% were classified as PM. 87% of them received PLX. Demographic data revealed no obvious differences between PM and good mobilizing (GM) patients. All patients were treated highly individualized prior to mobilization. Majority of all PM patients were able to undergo apheresis (95%) and reached their individual requested CD34+ progenitor cell target (72%). 57% of the PM patients achieved >2.0 × 106 CD34+ progenitor cells/kg body weight on day 1 of apheresis and nearby 70% of them underwent ASCT. Median time to engraftment was similar in PM and GM patients of the lymphoma cohort. Conclusions: Majority of PM patients with lymphoma were successfully mobilized and underwent ASCT. Most of them received PLX during the study.

Modern Total Knee Arthroplasty Bearing Designs and the Role of the Posterior Cruciate Ligament.

The role of the posterior cruciate ligament (PCL) in total knee arthroplasty (TKA) surgery continues to be a source of debate among the adult reconstruction community. In native knee flexion, the PCL is comprised of an anterolateral and posteromedial bundle that work together to limit posterior tibial translation and allow adequate femoral rollback for deep flexion. In the arthritic knee, the PCL can often become dysfunctional and attenuated, which led to the development of posterior stabilized (PS) TKA bearing options. PS TKAs implement a cam-post construct to functionally replace a resected PCL. While PS designs may facilitate balancing knees with significant deformity, they are associated with complications such as postfracture, increased wear, and patellar clunk/crepitus. In recent years, newer designs have been popularized with greater degrees of congruency and incorporation of medial and lateral pivoting to better recreate native knee kinematics. The American Joint Registry has confirmed the recent predilection for ultra-congruent and cruciate-retaining TKA inserts over PS TKAs during the last decade. Studies have failed to identify an overall clinical superiority between the cruciate substituting and sacrificing designs. The literature has also failed to identify clinical consequences from PCL resection with modern, more conforming TKA designs. In this article, we review modern PCL sacrificing designs and discuss the impact of each on the kinematics after TKA. We also will delineate the role of the PCL in modern TKA in the hopes to better understand the recent surge in sacrificing but not substituting knee implants.

Predictors of Adverse Events in the Surgical Treatment of Adult Distal Humerus Fractures.

The purpose of this study was to identify surgical complications after distal humerus fracture fixation as well as correlations between these complications and patient variables. A total of 132 patients underwent open reduction and internal fixation of traumatic distal humerus fractures between October 2011 and June 2018. Included were adult patients who underwent surgical fixation and had more than 6 months of follow-up. Excluded were patients with inadequate radiographic imaging, less than 6 months of follow-up, and previous distal humerus surgery. Multivariate logistic regression models controlling for age and body mass index were used to determine preoperative factors predictive of postoperative complications. A total of 73 patients were included in this analysis. Surgical complications were reported for 17 patients. Reoperation was required for 13 patients. Open injury at presentation was predictive of delayed union. Predictors of subsequent elbow surgery included younger age, polytrauma, open fracture, and ulnar nerve injury at the time of injury. Radial nerve injury at the time of presentation was also a risk factor for postoperative radial nerve symptoms. Predictors of postoperative heterotopic ossification included older age. Thirty-one patients had an olecranon osteotomy during their open reduction and internal fixation and none went on to nonunion. There were 13 patients with ulnar nerve complications. Of these patients, 3 had undergone an ulnar nerve transposition. None of the other studied variables were predictors of complications, malunion, or nonunion at latest follow-up. Although open reduction and internal fixation is effective in treating distal humerus fractures, its complications cannot be overlooked. Open fractures are more likely to go on to delayed union. Ulnar nerve injury, open fracture, and polytrauma were predictive for reoperation. Older patients were less likely to have subsequent surgery but more likely to develop heterotopic ossification. By identifying at-risk patients, managing physicians can better prognosticate and counsel patients on their recovery. [Orthopedics. 2023;46(6):352-357.].

Widely applicable, extended flow cytometric stem cell enumeration panel for quality control of advanced cellular products.

The most widely used quality control assay for CD34 + hematopoietic stem cell product characterization is the protocol established by the International Society of Hematotherapy and Graft Engineering (ISHAGE). While this protocol is still the gold standard for stem cell enumeration and viability assessment, it does not include T cell enumeration, which is nowadays mandatory for assaying standard allogeneic grafts and various advanced therapy medicinal products (ATMPs). In accordance, we have developed and extensively validated a new approach for a more comprehensive characterization of hematopoietic cellular products using a pre-formulated dried antibody format panel. In addition to the counting beads, the typical markers CD45 fluorescein isothiocyanate (FITC) and CD34 phycoerythrin (PE), as well as the viability dye 7-amino actinomycin D (7-AAD), our novel pre-formulated panel also contains CD3 Pacific Blue (PB) and CD19 allophycocyanin (APC) in the same tube, thereby allowing a combined calculation of leucocytes, stem cells, T and B cells. Showing high linearity, sensitivity and accuracy, our approach is easy to implement and enables a more in-depth characterization of the cellular product under release testing conditions. In addition, the dried pre-formulated antibody approach increases assay reliability compared to the standard antibody panel.

Use of the Hybrid Operating Room for Pelvic and Acetabular Fracture Surgery.

The hybrid operating room (HOR) utilizes advanced imaging technology to improve intra-operative visualization and facilitate efficient care in procedures that are relatively image dependent. The robotic C-arm provides improved 2D image quality and is capable of large volume three-dimensional fluoroscopy (3DF) that can rapidly create multiplanar CT like images. Here we discuss on the technique, utility, potential benefits, pitfalls, and complications of using the hybrid suite with and without intra-arterial balloon occlusion for pelvic and acetabular fracture surgery. We also present a case series of patient who underwent pelvic fixation using the HOR. While not advocated for routine use in all pelvic and acetabular fractures; the hybrid suite can be an effective tool in the treatment of complex cases and may facilitate efficient care of the hemodynamically unstable patient. It should be considered when resuscitative stabilization, angioembolization, intra-arterial balloon occlusion, or life-threatening bleeding is anticipated. Additionally, use of the hybrid room allows access to 3D fluoroscopy, and the associated benefits, if a mobile 3D unit is otherwise unavailable. These benefits must be weighed against the cumbersome table, the potential pitfalls with patient size and positioning, and the increased cost to the hospital.

An Atypical Adverse Local Tissue Reaction After Ceramic-on-Ceramic Primary Total Hip Arthroplasty.

Adverse local tissue reaction is an uncommon but frequently described complication after total hip arthroplasty (THA). It is most often associated with metal-on-metal hips and less frequently with metal-on-polyethylene implants as part of a mechanically assisted crevice corrosion process. In this report, we describe a rare case of an atypical adverse local tissue reaction in a patient with a ceramic-on-ceramic THA. Abrasive backside liner wear from a prominent screw head, failure of the liner locking mechanism, and liner fragmentation secondary to component-component impingement created an atypical mass and fluid collection leading to THA failure. This case demonstrates the importance of appropriate cup-liner positioning, thorough workup of pain after THA, and the ability of ceramic debris to cause an associated, atypical adverse local tissue reaction.

Systematic Review and Meta-Analysis of Intrawound Vancomycin in Total Hip and Total Knee Arthroplasty: A Continued Call for a Prospective Randomized Trial.

BACKGROUND: Periprosthetic joint injection (PJI) is a rare, but life-altering complication of total joint arthroplasty (TJA). Though intrawound vancomycin powder (IVP) has been studied in other orthopedic subspecialties, its efficacy and safety in TJA has not been established. METHODS: PubMed and MEDLINE databases were used to identify studies utilizing IVP in primary and revision total hip (THA) and knee arthroplasty (TKA). Postoperative PJI data were pooled using random effect models with results reported as odds ratios (ORs) and 95% confidence intervals (CIs). Studies were weighted by the inverse variance of their effect estimates. RESULTS: Overall, 16 of the 1871 studies identified were pooled for final analysis, yielding 33,731 patients totally. Of these, 17 164 received IVP. In aggregate, patients who received IVP had a decreased rate of PJI (OR 0.46, P < .05). Separately, TKA and THA patients who received IVP had lower rates of PJI (OR 0.41, P < .05 and OR 0.45, P < .05, respectively). Aggregate analysis of primary TKA and THA patients also revealed a decreased PJI rate (OR 0.44, P < .05). Pooled revision TKA and THA patients had a similar decrease in PJI rates (OR 0.30, P < .05). Although no publication bias was appreciated, these findings are limited by the low-quality evidence available. CONCLUSION: While IVP may reduce the risk of PJI in primary and revision TJA, its widespread use cannot be recommended until higher-quality data, such as that obtained from randomized control trials, are available. This study underscores the continued need for more rigorous studies before general adoption of this practice by arthroplasty surgeons.

Adverse Events Following Minimally Invasive Achilles Tendon Repair.

BACKGROUND: The rate of wound complications following traditional open Achilles tendon repair is reported at 7.6%. The purpose of this study is to characterize the rate of wound and other early complications following a specific minimally invasive Achilles tendon repair technique, and to identify any factors associated with increased risk. METHODS: The postoperative courses of 99 patients who underwent minimally invasive Achilles tendon repair by 2 surgeons at separate academic medical centers were retrospectively reviewed. Mean follow-up was 8.1 months (range 3.0-24.6 months). Repair technique was similar in all cases with the exception that 71 procedures used a longitudinal incision and a tourniquet, while 28 procedures used a transverse incision and no tourniquet (surgeon preference). The rates of complications were compared between patients with differing baseline and procedural characteristics. RESULTS: Of the 99 patients included in the study, 2 (2.0%) developed wound complications. There was no statistical difference in the rate of wound complications between patients in the longitudinal incision/tourniquet group and patients in the transverse incision/no tourniquet group (2.8% vs 0%; P = 1.000). Four patients (4.0%) developed sural neuropraxia. One patient developed deep venous thrombosis. There were no cases of rerupture. At final follow-up, all 99 patients had intact Thompson tests and well-healed wounds. CONCLUSIONS: The rate of wound complications following minimally invasive Achilles tendon repair is low at 2.0%. Patients should be counseled that although risk for wound complications may be lower with this minimally invasive technique, there are risks for sural neuropraxia and deep suture reaction. LEVELS OF EVIDENCE: Level III, Retrospective study.

Surface Mapping of the Musculotendinous Attachments at the Pubic Symphysis in Cadaveric Specimens: Implications for the Treatment of Core Muscle Injury.

PURPOSE: To characterize the 3-dimensional muscular, musculotendinous, and neurovascular anatomy about the pubic symphysis relevant to core muscle injury (CMI). METHODS: Ten cadaveric hips were dissected to characterize the musculotendinous insertion of the rectus abdominis and inguinal ligament, origins of the adductor longus and adductor brevis, and the pubic cartilage plate. A 3-dimensional coordinate measuring system and data acquisition software were used to calculate structure cross-sectional area, and the landmark anatomical relationships to 1 another and relevant neurovascular structures. RESULTS: All specimens were male with an average age of 62 ± 2 years. The mean footprints of the rectus abdominis, inguinal ligament, adductor longus, and adductor brevis were 8.4 ± 3.1, 1.2 ± 0.5, 3.8 ± 1.6, and 2.9 ± 1.3 cm2, respectively. The mean pectineus and gracilis footprints were 6.3 ± 2.4 and 3.4 ± 0.9 cm2, respectively. The mean cross-sectional area of the cartilage plate was 24.8 ± 5.6 cm2. The adductor longus was an average 1.5 ± 0.25 cm from the adductor brevis and 0.69 ± 0.52 cm from the rectus abdominis. The genital branch of the genitofemoral nerve was an average of 4.3 cm (range, 2.8-6.4) lateral to the insertion of the inguinal ligament. The femoral vein and artery were 3.0 cm (range, 2.5-3.6) and 3.7 cm (range, 2.5-5.9) lateral to the inguinal ligament footprint. The obturator nerve was 2.5 cm (range, 1.6-3.4) lateral to the adductor longus. CONCLUSIONS: Familiarity with the anatomy of the pubic symphysis is essential for surgeons treating patients with CMI. We have shown that this relatively small area is the site of many muscular, musculotendinous, and neurovascular structures with various sized footprints and described the 3-dimensional anatomy of the anterior pubic symphysis. The origin of the adductor longus lies in close proximity to other structures, such as the adductor brevis, the insertion of the rectus abdominis, and the obturator nerve. These findings should be considered when operating in this region and treating patients with chronic groin pain. CLINICAL RELEVANCE: The anatomy of the pelvic region and pubic symphysis has not been well characterized. Intimate knowledge of relevant anatomy is essential to treating CMI, also known as athletic pubalgia or sports hernia.

Comparison of Stand-alone Lateral Lumbar Interbody Fusion Versus Open Laminectomy and Posterolateral Instrumented Fusion in the Treatment of Adjacent Segment Disease Following Previous Lumbar Fusion Surgery.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The aim of this study was to compare clinical and radiographic outcomes of patients who underwent stand-alone lateral lumbar interbody fusion (LLIF) to those who underwent posterolateral fusion (PLF) for symptomatic adjacent segment disease (ASD). SUMMARY OF BACKGROUND DATA: Recent studies have suggested that LLIF can successfully treat ASD; however, there are no studies to date that compare LLIF with the traditional open PLF in this cohort. METHODS: A total of 47 consecutive patients who underwent LLIF or PLF for symptomatic ASD between January 2007 and August 2016 after failure of conservative management were reviewed for this study. Patient-reported outcomes (PROs) were collected on all patients at preoperative, postoperative, and most recent post-operative visit using the Oswestry Disability Index, Visual Analog Scale (VAS)-Back, and VAS-Leg surveys. Preoperative, immediate postoperative, and most recent postoperative radiographs were assessed for pelvic incidence, fusion, intervertebral disc height, segmental and overall lumbar lordosis (LL). Symptomatic ASD was diagnosed if back pain, neurogenic claudication, or lower extremity radiculopathy presented following a previous lumbar fusion. Preoperative plain radiographs were evaluated for evidence of adjacent segment degeneration. RESULTS: A total of 47 patients (23 LLIF, 24 PLF) met inclusion criteria. Operative times (P < 0.001) and intraoperative blood loss (P < 0.001) were significantly higher in the PLF group. Patients who underwent PLF were discharged approximately 3 days after the LLIF patients (P < 0.001). PROs in the PLF and LLIF cohorts showed significant and equivalent improvement, with equivalent radiographic fusion rates. LLIF significantly improve segmental lordosis (P < 0.001), total LL (P = 0.003), and disc height (P < 0.001) from preoperative to immediate postoperative and final follow-up (P = 0.004, P = 0.019, P ≤ 0.001, respectively). CONCLUSION: Although LLIF may provide less perioperative morbidity and shorter length of hospitalization, both techniques are safe and effective approaches to restore radiographic alignment and provide successful clinical outcomes in patients with adjacent segment degeneration following previous lumbar fusion surgery. LEVEL OF EVIDENCE: 3.

How Should We Define Clinically Significant Outcome Improvement on the iHOT-12?

BACKGROUND: There is increased emphasis on efficiently administering patient-reported outcome measures (PROMs). The International Hip Outcome Tool-12 (iHOT-12) is a short-form version of the iHOT-33, and relatively little is known about clinically significant outcomes using the iHOT-12. QUESTIONS/PURPOSES: The purpose of this study was to define minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) for the iHOT-12 and to identify predictors for achieving these psychometric end points in patients undergoing arthroscopic treatment of femoroacetabular impingement (FAI). METHODS: Data was prospectively collected and retrospectively analyzed as part of an institutional hip preservation repository. One hundred and twenty patients were included; mean age and body mass index (BMI) were 38.7 years and 25.9, respectively. A majority of patients were female (67.5%) and white (81.7%) and participated in recreational sports (79.2%). The iHOT-12 was administered pre-operatively and at 1-year follow-up to patients undergoing primary hip arthroscopy for FAI. The following anchor question was also asked at 1-year follow-up: "Taking into account all the activities you have during your daily life, your level of pain, and also your functional impairment, do you consider that your current state is satisfactory?" MCID was calculated using a distribution-based method. Receiver-operating characteristic analysis with area under the curve was used to confirm the significance of the PASS threshold. RESULTS: Mean iHOT-12 scores improved from 35.6 at pre-operative assessment to 70.7 at 1-year follow-up. Patients indicating satisfaction with their outcome improved from 37.5 pre-operatively to 79.0 at 1-year follow-up. MCID value for the iHOT-12 was 13.0. The PASS threshold was 63.0, indicating an excellent predictive value that patients scoring above this threshold were likely to have met an acceptable symptom state. Worker's compensation patients and those with increased BMI were less likely to achieve PASS; lower pre-operative iHOT-12 score was predictive for achieving MCID, and achieving MCID was predictive for achieving PASS. CONCLUSION: This is the first study to define PASS and MCID for the iHOT-12, which measures clinically significant outcome improvement comparably to that of other commonly used hip PROMs. As its use becomes more widespread, the iHOT-12 data-points presented in this study can be used to determine clinically significant improvement of patient-reported outcomes.

Systematic Review of Hip Arthroscopy for Femoroacetabular Impingement: The Importance of Labral Repair and Capsular Closure.

PURPOSE: To evaluate the safety and efficacy of hip arthroscopy for femoroacetabular impingement syndrome by assessing complications, comprehensive procedure survivorship, and the influence of labral and capsular management on procedure survivorship. METHODS: A systematic review of multiple medical databases was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and checklist. All clinical outcome studies that reported on the presence or absence of reoperation after hip arthroscopy for femoroacetabular impingement syndrome were eligible for inclusion. Data pertaining to patient demographic characteristics, surgical technique (specifically labral and capsular management), patient-reported outcomes, complications, reoperation, and conversion to arthroplasty were extracted from each study. RESULTS: A total of 68 studies (7,241 hips) were included. Most were Level IV studies (63%). Complications occurred in 1.9% of cases. The most common complications were neurologic (53%), heterotopic ossification (24%), infection (15%), and thromboembolic (7%). Conversion to total hip arthroplasty (456 cases) was the most common reason for reoperation, followed by revision hip arthroscopy (226 cases) and periacetabular osteotomy (7 cases). The rate of arthroplasty conversion was lower than 10% in 43 of 59 studies reporting this outcome. The average interval to arthroplasty conversion was 58 months. Between 2009 and 2017, the performance of labral repair increased from 19% to 81% of cases and capsular closure increased from 7% to 58% of cases. CONCLUSIONS: Arthroplasty conversion occurred in fewer than 10% of cases in the clear majority of series. Labral repair (compared with labral debridement) and capsular closure (compared with unrepaired capsulotomy) were associated with a lower risk of conversion to arthroplasty. Throughout the study interval, there were shifts in surgical technique favoring labral repair over debridement and capsular repair over unrepaired capsulotomy. The study is limited by selection bias because cases in which labral and capsular repair was performed may have had superior tissue that was more amenable to repair. LEVEL OF EVIDENCE: Level IV, systematic review.

The Duration of Symptoms Does Not Impact Clinical Outcomes Following Lumbar Decompression Surgery.

STUDY DESIGN: A retrospective cohort analysis. OBJECTIVE: The aim of this study was to assess whether duration of symptoms (DOS) has an effect on clinical outcomes in patients undergoing lumbar decompression. SUMMARY OF BACKGROUND DATA: The success of surgical interventions for lumbar spinal stenosis varies depending on numerous factors, including DOS. However, existing literature does not provide a clear indication of the outcome of lumbar decompression surgery in regard to DOS secondary to nerve root compression. METHODS: Analysis of patients who underwent primary lumbar laminectomy from 2008 through 2015 by one of two senior orthopedic spine surgeons was conducted. Exclusion criteria were as follows: previous lumbar surgery, patient under 18 years of age at time of surgery, or postoperative follow-up less than 3 months. Patients were divided into groups on the basis of preoperative DOS: less than 1 year and 1 year or greater. Patient-reported outcomes were obtained using Oswestry Disability Index (ODI) scores, Visual Analog Scales (VAS) scores for the back and leg, 12-Item Short Form Mental and Physical Survey (SF-12) scores, and Veterans Rand 12-Item Health Mental and Physical Survey (VR-12) scores. Patients were surveyed about expectations and postoperative satisfaction. RESULTS: Two hundred ten patients were assessed; 108 with DOS of less than 1 year and 102 with DOS of 1 year or more. On multivariate analysis, patients with DOS of 1 year or greater presented with significantly lower SF-12 scores (P = 0.043). No significant differences existed in other outcome survey scores. Reoperation rates were not significantly different (P = 0.904). Both groups reported high levels of satisfaction (odds ratio 0.42, P = 0.483) and that surgery met or exceeded their expectations (odds ratio 1.00, P = 0.308). CONCLUSION: Symptom chronicity did not significantly affect postoperative clinical outcomes, reoperation rates, or patient satisfaction. Nonoperative treatment of lumbar spinal stenosis is often successful but may delay operative intervention. However, results of this study suggest that the delay does not negatively impact surgical outcomes. LEVEL OF EVIDENCE: 3.

The Effect of Preoperative Symptom Duration on Postoperative Outcomes After a Tubular Lumbar Microdiscectomy.

STUDY DESIGN: This is a retrospective cohort study. OBJECTIVE: This study aims to characterize the effect of preoperative symptom duration on postoperative outcomes after minimally invasive lumbar microdiscectomy (MIS LD). SUMMARY OF BACKGROUND DATA: It is unknown whether extended nonoperative treatment before MIS LD has implications for long-term clinical outcomes even after surgery is performed. MATERIALS AND METHODS: A prospectively maintained surgical registry of patients undergoing MIS LD by a single surgeon between 2013 and 2017 was reviewed. Preoperative symptom duration was dichotomized into 2 groups (≤6 and >6 mo). Only patients with full clinical data at 6 months postoperative follow-up were included in the study. Clinical outcomes were assessed at 6, 12 weeks, and 6 months after surgery. The number of patients obtaining a minimum clinically important difference was assessed. Groups were compared with the χ analysis and the student t tests for categorical and continuous data, respectively. RESULTS: In total, 94 patients were identified. A total of 45 patients (47.9%) had symptom duration ≤6 months. No differences in baseline characteristics were found (P>0.05). Patients with shorter symptom duration had significantly greater improvement in Oswestry Disability Index scores at 6 weeks (P=0.004), 12 weeks (P=0.022), and 6 months (P=0.005). Patients with shorter duration of symptoms also obtained minimum clinically important difference for Oswestry Disability Index at a greater rate than those with longer duration of symptoms (P=0.015). CONCLUSIONS: Although patients who underwent MIS LD within 6 months of symptom onset had similar baseline characteristics compared with patients who underwent surgery after 6 months of symptoms, the patients with longer preoperative symptom duration had worse functional outcomes at 6 months after surgery. These results suggest that earlier MIS lumbar microdiscectomy may provide a functional benefit for patients. Further studies should therefore evaluate the efficacy of nonoperative treatment in the setting of lumbar herniated nucleus pulposus, as prolonged conservative management may potentially impair functional recovery after surgery.

Internal Validation of a Predictive Model for Complications After Total Hip Arthroplasty.

BACKGROUND: Total hip arthroplasty (THA) is projected to increase in prevalence and associated complications will impose significant cost on the US healthcare system. The purpose of this study is to validate a predictive model for postoperative complications utilizing a novel 11-component hip-specific questionnaire encompassing preoperatively available clinical and radiographic data. METHODS: Consecutive primary THA patients between January 2014 and January 2016 were included. Exclusion criteria included patients without questionnaire scoring variables and less than 1-year follow-up. Patients were stratified into 4 tiers based on their questionnaire score: low risk (>74), mild risk (57-73), moderate risk (41-56), and high risk (<40). A binary logistic regression was performed to determine if the questionnaire predicted complications. Receiver-operator curves were constructed to determine the threshold score below which there was a high likelihood of experiencing a complication. RESULTS: Four hundred fifty patients were included in the final analysis with a mean (range) follow-up of 2.1 years (1.0-5.9), age of 63.1 years (25.7-9.17), and body mass index of 31.7 kg/m2 (17.8-64.5). The complication rate was 13.6%. A hip questionnaire score of 73.8 conferred a 98.5% sensitivity and 98.5% negative predictive value for complications. The questionnaire score was the strongest predictor of a decreased complication likelihood (odds ratio 0.94, 95% confidence interval 0.90-0.97, P < .001). Risk tier was significantly associated with complications (low risk: 0; mild risk: 12; moderate risk: 25; and high risk: 24; P < .001). CONCLUSION: This novel hip questionnaire demonstrated a high sensitivity and negative predictive value to identify patients at risk for postoperative complications. Future studies should attempt to prospectively validate the use of this questionnaire.

Multi- versus single-level anterior cervical discectomy and fusion: comparing sagittal alignment, early adjacent segment degeneration, and clinical outcomes.

PURPOSE: The purpose of this study was to compare the rates of adjacent segment degeneration (ASD), sagittal alignment parameters, and patient-reported outcomes in patients who underwent multi-level versus single-level anterior cervical discectomy and fusion (ACDF). METHODS: A retrospective cohort analysis was performed on consecutive patients who underwent an ACDF. Pre- and post-operative radiographic assessment included ASD, change in C2-C7 lordosis, T1 angle, levels fused, sagittal vertical axis (SVA), fusion mass lordosis, proximal and distal adjacent segment lordosis. Patient-reported outcomes were obtained. RESULTS: Of the 404 that underwent an ACDF with a minimum of 6 months of follow-up (average 28 months), there was no significant difference in the rate of radiographic ASD overall (p = 0.479) or in the proximal or distal adjacent segments on multivariate analysis. Secondarily, the multi-level fusions appear to restore significantly greater amounts of lordosis compared to single-level procedures (p < 0.001) and are able to maintain the corrected cervical lordosis and fusion segment lordosis over time. From the immediate post-operative period to final follow-up, the single-level ACDFs show continuing lordosis improvement (p = 0.005) that is significantly greater than that of the multi-level constructs. There were no significant differences between pre-operative, post-operative, or change in patient-reported outcomes. CONCLUSIONS: Two years following an ACDF, patients who underwent multi-level fusions appear to restore significantly greater amounts of lordosis compared to single-level procedures, while single-level ACDFs show significantly greater amounts of lordosis improvement over time. Multi-level procedures may not be at a significantly greater risk of developing early radiographic evidence of ASD compared to single-level procedure. These slides can be retrieved under Electronic Supplementary Material.

High Rate of Return to High-Intensity Interval Training After Arthroscopic Management of Femoroacetabular Impingement Syndrome.

BACKGROUND: Since the inception of CrossFit in 2000, the popularity of high-intensity interval training (HIIT) in the United States has risen dramatically. While HIIT is a highly efficient exercise for weight loss and improved conditioning, some literature reports injuries in up to 34% of HIIT participants. We sought to evaluate the functional and sports-specific results of hip arthroscopic surgery in recreational HIIT participants. PURPOSE: To evaluate patients' ability to return to HIIT after hip arthroscopic surgery for femoroacetabular impingement syndrome (FAIS). STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Consecutive patients with FAIS who had identified themselves as participating in HIIT and had undergone hip arthroscopic surgery for the treatment of FAIS by a single fellowship-trained surgeon between 2012 and 2015 were reviewed. Demographic data; preoperative physical examination findings; preoperative imaging results; preoperative patient-reported outcome (PRO) scores including the modified Harris Hip Score (mHHS), Hip Outcome Score-Activities of Daily Living (HOS-ADL), Hip Outcome Score-Sports-Specific Subscale (HOS-SSS), and visual analog scale (VAS) for pain; and postoperative examination and PRO scores at a minimum 2 years after surgery, including a HIIT-specific questionnaire, were assessed for all patients. RESULTS: Thirty-two patients (13 male, 19 female) with a mean age of 34.7 ± 6.9 years (range, 21-49 years) were identified with a minimum 24-month follow-up. Among these, 22 participated in CrossFit, 4 in Shred415, 3 in Orangetheory, and 3 in self-directed cross-training including plyometrics. Preoperatively, 14 patients had discontinued HIIT because of activity-related hip complaints, 17 patients had scaled back involvement in HIIT, and 1 patient maintained her baseline routine. Postoperatively, 28 of 32 patients (88%) returned to HIIT at a mean of 9.8 ± 5.7 months after surgery (range, 3-24 months); 96% returned to HIIT at the same level as or better than before the injury. Fear of reinjury was the most common reason for cessation (3/4). Preinjury and postoperative involvement in HIIT were comparable (5.3 vs 5.1 h/wk, respectively; P = .8). All patients had significant improvements in the HOS-ADL score (69.7 ± 17.3 to 94.2 ± 8.4; P < .001), HOS-SSS score (49.2 ± 21.2 to 83.3 ± 21.4; P < .001), mHHS score (59.9 ± 14.2 to 85.4 ± 11.6; P < .001), and VAS for pain score (7.5 ± 1.8 to 1.1 ± 1.3; P < .001) from preoperatively to postoperatively. CONCLUSION: Arthroscopic treatment of FAIS in recreational HIIT participants resulted in significant improvements in hip function and predictably high rates of patient satisfaction. Postoperatively, 88% of patients returned to HIIT, 44% noted improvement from preinjury HIIT performance, and the mean weekly participation was comparable with before the injury.

Authorship Trends in Spine Publications From 2000 to 2015.

STUDY DESIGN: Literature review. OBJECTIVE: To examine changes in authorship characteristics for Spine publications from the year 2000 to 2015. SUMMARY OF BACKGROUND DATA: Scientific publications are considered an indication of academic achievement for physicians. Recently, authorship trends have been investigated; however, limited information is available on this topic within spine-specific literature. METHODS: Original research articles published in Spine in the years 2000, 2005, 2010, and 2015 were evaluated. Authorship characteristics were collected for each article, including the number of authors and institutions per publication, first and last authors' sex, publication origin, and highest degree held by the first and last author. Trends over time were analyzed using numeric and visual descriptive analyses including percentages, means, standard deviations, and graphs. RESULTS: An average of 506 articles per year was published in Spine during the years 2000, 2005, 2010, and 2015. The number of articles written by 10 or more authors increased during this time (0.9%-14.4%). There was a substantial increase in the number of multiple institutional affiliations (33.6%-68.7%) and articles originating from outside North America (47.6%-55.7%) from 2000 to 2015. The percentage of first authors with bachelor's degrees was higher in 2015 (6.6%) as compared to 2000 (1.4%), and more last authors were identified as MD/PhDs in 2015 (19.2%) than in 2000 (10.0%). Similar female representation was noted for first and last authorship for all years evaluated. CONCLUSION: The results of this study demonstrate increases in authors per article published in Spine from 2000 to 2015. In addition, first authors were more likely to hold bachelor's degrees over time. This may be attributed to increasing competition in spine-related fields, necessitating earlier research exposure to aid in academic achievement. Interestingly, the percentage of female authorship has not changed significantly over time, in contrast with much of the previous literature. LEVEL OF EVIDENCE: 2.