Outcomes of Flexibility Sport Athletes With Borderline Hip Dysplasia After Hip Arthroscopy for Femoroacetabular Impingement Syndrome: A Propensity-Matched Analysis at Minimum 2-Year Follow-up

BACKGROUND

Hip arthroscopy has proved successful in treating femoroacetabular impingement syndrome (FAIS) in patients with and without borderline hip dysplasia (BHD). Despite a high prevalence of BHD in patients who participate in sports with high flexibility requirements, a paucity of literature evaluates the efficacy of hip arthroscopy in treating FAIS in flexibility sport athletes with BHD.

PURPOSE

To compare minimum 2-year patient-reported outcomes (PROs) and achievement of clinically significant outcomes in flexibility sport athletes with BHD undergoing primary hip arthroscopy for FAIS with capsular plication with results in flexibility sport athletes without dysplasia.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were prospectively collected for patients undergoing primary hip arthroscopy for FAIS with BHD, defined as a lateral center-edge angle of 18° to 25°, who reported participation in a sport with a high flexibility requirement, including dance, gymnastics, figure skating, yoga, cheerleading, and martial arts, according to previous literature. These patients were matched 1:2 to flexibility sport athletes without dysplasia, controlling for age, sex, and body mass index. Preoperative and minimum 2-year postoperative PROs were collected and compared between groups. Cohort-specific minimal clinically important difference and patient acceptable symptom state achievement was compared between groups.

RESULTS

In total, 52 flexibility sport athletes with BHD were matched to 104 flexibility sport athletes without BHD. Both groups showed similar sport participation (P = .874) and a similar level of competition (P = .877). Preoperative lateral center-edge angle (22.2°± 1.6° vs 31.5°± 3.9°; P < .001) and Tönnis angle (10.9°± 3.7° vs 5.8°± 4.4°; P < .001) differed between groups. Capsular plication was performed in all cases. Both groups achieved significant improvement in all PROs (P < .001) with no differences in postoperative PROs between groups (P≥ .147). High minimal clinically important difference (BHD group: 95.7%; control group: 94.8%) and patient acceptable symptom state (BHD group: 71.7%; control group: 72.2%) achievement for any PRO was observed with no differences between groups (P≥ .835).

CONCLUSION

Flexibility sport athletes with BHD achieved similar outcomes as those of flexibility sport athletes without BHD after hip arthroscopy for FAIS with capsular plication.

Hip Arthroscopy Patients with Lower Back Pain Show Delayed Clinical Improvement and Inferior Time-Dependent Survivorship: A Propensity Matched Study at Mid-Term Follow-Up

PURPOSE

To evaluate patient-reported outcomes (PROs) and survivorship at mid-term follow-up after hip arthroscopy (HA) for femoroacetabular impingement syndrome (FAIS) in patients with and without preoperative lower back pain (LBP).

METHODS

Patients with self-endorsed preoperative LBP who underwent HA for FAIS with mid-term follow-up were identified and propensity matched 1:1 to patients without back pain by age, sex, and body mass index. PROs collected preoperatively and at postoperative years 1, 2, and 5 included: Hip Outcome Score Activities of Daily Living (HOS-ADL) and Sports Subscale (HOS-SS), International Hip Outcome Score 12 (iHOT-12), modified Harris Hip Score (mHHS), Visual Analog Scale (VAS) for Pain. Achievement of minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) were compared. Survivorship was compared with Kaplan-Meier analysis.

RESULTS

119 patients with LBP were matched to 119 patients without LBP. Group demographic factors were as follows, age (37.4±11.9 years vs 37.6±12.6, p=0.880), sex (64.4% female vs 67.7%, p=0.796), and BMI (25.3±5.1 kg/m2 vs 25.3±5.4, p=0.930). Average follow-up duration was 6.0 ± 1.9 years. LBP patients showed similar preoperative PROs, yet lower 1-year scores for all PROs (p ≤ 0.044). At final follow-up, similar PROs were shown between groups (p ≥ 0.196). LBP and non-LBP patients had similar MCID achievement for HOS-ADL (59.3%vs.63.1%,p=0.640), HOS-SS (73.9%vs.70.8%,p=0.710), mHHS (66.7%vs.73.4%, p=-.544), iHOT-12 (85.1%vs.79.4%,p=0.500), and VAS-Pain (75.6%vs.69.9%,p=0.490). Groups also had similar PASS achievement for HOS-ADL (63.5%vs.61.3%,p=0.777), HOS-SS (57.0%vs.62.5%,p=0.461), mHHS (81.9%vs.79.1%, p=0.692), iHOT-12 (54.6%vs.61.2%,p=0.570), and VAS-Pain (51.0%vs.55.4%,p=0.570). with similar MCID (p ≥ 0.490) and PASS (p ≥ 0.386) achievement. Conversion to total hip arthroplasty occurred in 3.4% of hips with LBP and 0.8% of hips without LBP (p=0.370), Back pain patients demonstrated inferior time-dependent survivorship compared to patients without back pain on Kaplan-Meier survival analysis (p = 0.023).

CONCLUSIONS

Patients undergoing primary hip arthroscopy for femoroacetabular impingement syndrome with LBP achieve comparable PROs and CSOs to patients without back pain at mid-term, despite lower 1-year PRO scores. LBP patients show inferior reoperation-free time-dependent survivorship compared to those without LBP.

Computer-Assisted Arthroscopic Cam Resection

Determining the appropriate femoral cam resection during hip arthroscopy for femoroacetabular impingement syndrome is both critical for the patient and challenging for the surgeon. Incomplete bone resection is a leading cause of failed hip arthroscopy, whereas over-resection may increase the risk of femoral neck fracture. The alpha angle is a validated 2-dimensional radiographic measurement used to both diagnose femoroacetabular impingement syndrome preoperatively and to determine resection adequacy postoperatively. Computer-assisted intraoperative guidance systems enhance the accuracy of femoral cam resection, although a preoperative 3-dimensional computed tomography scan may be required. Other systems, such as the HipCheck software (Stryker, Kalamazoo, MI), have been developed to provide intraoperative guidance with live feedback using simultaneous alpha angle measurements overlayed on fluoroscopic images without the requirement for routine preoperative computed tomography. Via intraoperative touchscreen navigation, the surgeon identifies the midpoint of the femoral neck and femoral head. A commercial software program provides real-time alpha angle measurements, as well as enhanced visualization of the femoral cam deformity with an adjustable resection curve. Before the surgeon performs the cam resection, the software provides a template for appropriate resection depth in 6 positions of the hip. Upon completion of the femoral cam resection, the hip is again assessed in the same 6 positions and the alpha angle is assessed to ensure a complete resection.

Increased Alpha Angles and Younger Age Increase the Risk of Contralateral Femoral Acetabular Impingement Syndrome Symptom Development and Surgical Intervention: A Systematic Review

PURPOSE

To identify the preoperative risk factors associated with contralateral symptom development and surgical intervention for patients presenting with unilateral femoral acetabular impingement (FAI) syndrome.

METHODS

A literature search was performed using PubMed and Scopus computerized databases according to the 2020 Preferred Reporting Items for Systematic Meta-Analyses guidelines. Studies evaluating preoperative risk factors associated with the contralateral progression of FAI were included. Quality assessment was completed using the Methodological Index for Non-Randomized Studies criteria.

RESULTS

A total of 5 studies (n = 1,011 patients; mean age, 29.9 years) published from 2013 to 2022 met the inclusion/exclusion criteria. Mean follow-up ranged from 12 to 132 months. The overall rate of contralateral progression of symptomatic FAI ranged from 32.4% to 81%. Increased alpha angle was frequently reported factor associated with contralateral symptom progression, followed by decreased total arc of rotation, decreased internal rotation, reduced neck-shaft angle, and head-neck offset. The incidence rate of progression to contralateral surgery ranged from 15.7% to 24% of patients. Younger age was frequently reported factor associated with contralateral surgical intervention, followed by male sex, increased level of activity, and increased alpha angle.

CONCLUSIONS

Increased alpha angle and younger age were commonly reported risk factors associated with an increased risk of symptom development and surgical progression of contralateral FAI, respectively. The overall rate of contralateral progression of symptomatic FAI and the rate of progression to surgical intervention ranged up to 81% and 24%, respectively. This information may help both patients and surgeons to establish expectations regarding development of contralateral hip symptoms and possible need for surgery.

LEVEL OF EVIDENCE

Level III; systematic review of Level II-III studies.

Patients With Lateral and Anterolateral Cam Morphology Have Greater Deformities Versus Typical Anterolateral Deformity Alone but No Differences in Postoperative Outcomes: A Propensity-Matched Analysis at Minimum 5-Year Follow-Up

PURPOSE

To compare pre- and postoperative findings between patients undergoing hip arthroscopy for femoroacetabular impingement syndrome with lateral impingement versus those without lateral impingement METHODS: Patients who underwent primary hip arthroscopy for femoroacetabular impingement syndrome between 2012 and 2017 with minimum 5-year follow-up were included. Alpha angle (AA) was measured on preoperative anteroposterior (AP) and 90° Dunn radiographs. Patients with AA >60° on Dunn view but not AP view (no lateral impingement) were propensity matched by sex, age, and body mass index in a 1:3 ratio to patients with AA >60° on both views (lateral impingement). Demographic characteristics, radiographic and intraoperative findings, reoperation rates, and patient-reported outcomes (PROs) were compared between groups. Categorical variables were compared using the Fisher exact testing and continuous variable using 2-tailed Student t tests.

RESULTS

Sixty patients with lateral impingement (65.0% female, age: 35.3 ± 13.0 years) were matched to 180 patients without lateral impingement (65.0% female, age: 34.7 ± 12.5 years, P ≥ .279). Patients with lateral impingement had larger preoperative AAs on both Dunn (71.0° ± 8.8° vs 67.6° ± 6.1°, P = .001) and AP radiographs (79.0° ± 12.1° vs 48.2° ± 6.5°, P < .001). However, there were no differences in postoperative AAs on either view (Dunn: 39.0° ± 6.1° vs 40.5° ± 5.3°, AP: 45.8° ± 9.0° vs 44.9° ± 7.0°, P ≥ .074). Labral tears began more superiorly in patients with lateral impingement (12:00 ± 0:49 vs 12:17 ± 0:41, P = .030), and they demonstrated greater rates of acetabular and femoral cartilage damage (P = .030 for both); however, there were no differences in PROs or reoperation rates between the groups at 5-year follow-up.

CONCLUSIONS

Although cam deformities located laterally and anterolaterally are larger than those located anterolaterally alone, both can be resected adequately, resulting in similar postoperative radiographic measurements, PROs, and survivorship.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Gluteus Repair Yields Satisfactory Clinically Significant Outcome Achievement by 1 Year in Mostly Partial-Thickness Tears With Preoperative Hip Abduction Weakness Associated With Delayed Achievement

PURPOSE

To define the time to achievement of clinically significant outcomes (CSOs) after primary gluteus medius and/or minimus (GM) repair and to identify factors associated with delayed CSO achievement.

METHODS

Patients who underwent primary GM repair between January 2012 and June 2021 with complete preoperative, 6-month, 1-year, and 2-year Hip Outcome Score-Activities of Daily Living (HOS-ADL) were retrospectively identified. Cohort-specific minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) were calculated. The time to achievement of MCID and PASS was analyzed using Kaplan-Meier survival analysis. Median time to MCID and PASS achievement was recorded. Multivariate stepwise Cox regressions were used to identify factors associated with delayed CSO achievement.

RESULTS

Fifty GM repairs were identified (age 59.4 ± 9.7 years, body mass index 27.9 ± 6.2, 94% female). Tears were grade 1 in 39 cases, grade 2 in 7 cases, and grade 3 in 4 cases. Endoscopic repair was performed in 35 cases, and open repair was performed in 15 cases. Labral debridement and repair were each performed in 15 cases. Median time to CSO achievement was 5.7 months for MCID and 11.0 months for PASS. The 2-year cumulative probability of MCID and PASS achievement was 92.7% and 66.7%, respectively. Preoperative hip abduction weakness on physical examination was associated with delayed achievement of MCID (hazard ratio 2.27, confidence interval 1.067-7.41, P = .039) and PASS (hazard ratio 3.89, confidence interval 1.341-11.283, P = .012).

CONCLUSIONS

This study demonstrated that in patients undergoing repair of primarily grade 1 GM tears, most achieved MCID by 6 months, and more than one half achieved PASS by 12 months. Preoperative hip abduction weakness on physical examination was associated with delayed CSO achievement.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Patients Maintain Clinically Significant Outcomes at 5-Year Follow-Up after Hip Arthroscopy for Femoroacetabular Impingement Syndrome: A Systematic Review

PURPOSE

To assess 5-year outcomes and survival rate of hip arthroscopy (HA) for femoroacetabular impingement syndrome (FAIS) and to determine achievement rates of clinically significant outcomes.

METHODS

Three databases were searched around the following terms: hip arthroscopy, FAIS, and 5-year follow-up. Articles available in English, presenting original data, and reporting minimum 5-year follow-up after primary HA using either patient reported outcomes (PROs) or conversion to total hip arthroplasty (THA) and/or revision surgery were included. Quality assessment was completed using MINORS assessment, and relative agreement was calculated using Cohen's kappa.

RESULTS

Fifteen articles were included. MINORS assessment ranged from 11-22, with excellent (k=0.842) inter-rater reliability between reviewers. 2080 patients were included at a follow-up range of 60.0-84 months. Labral repair was the most commonly performed procedure (range: 8.0%-100%). All studies included PROs and all reported statistically significant improvement (p<0.05) at the 5-year timepoint. The most frequent PRO reported was modified Harris Hip Score (mHHS) (n=8). Nine studies reported on clinically significant outcome achievement, with mHHS being the most common (n=8). The rate of achieving minimal clinically important difference (MCID) ranged from 64-100%, patient-acceptable symptomatic state (PASS) ranged from 45-87.4%, and substantial clinical benefit (SCB) ranged from 35.3-66%. Conversion to THA and revision surgery varied across studies, with ranges of 0.0%-17.9% (duration: 28.8-87.1 months) and 1.3%-26.7% (duration: 14.8-83.7 months), respectively. The most common definition of failure was conversion to THA or revision (n=7). Increased age (n=5) and greater joint degeneration (n=4) were the most common predictors of clinical failure.

CONCLUSIONS

Patients undergoing primary hip arthroscopy for FAIS demonstrate significant improvement at 5-year follow-up, with maintained rates of achievement of MCID, PASS, and SCB. Survival rate of HA at 5-years is overall high, with ranges of 0.0-17.9% and 1.3-26.7% % conversion to THA or revision surgery, respectively. Across studies, increased age and greater joint degeneration were the most common cited predictors of clinical failure.

Capsular Repair is Associated with Lower Revision Rates Yet Similar Clinical Outcomes and Arthroplasty Conversion 5-Years after Hip Arthroscopy: A Systematic Review

PURPOSE

The purpose of this study was to perform a systematic review of studies reporting on minimum 5-year outcomes of patients undergoing primary hip arthroscopy (HA) for femoroacetabular impingement syndrome (FAIS) to determine whether capsular management influences patient-reported outcomes (PROs), rates of clinically significant outcome, and rates of revision surgery or conversion to total hip arthroplasty (THA).

METHODS

PubMed, Scopus, and Google Scholar were searched around the terms hip arthroscopy, FAIS, five-year follow-up, and capsule management. Articles available in English, presenting original data, and reporting minimum 5-year follow-up after HA using either PROs or conversion to THA and/or revision surgery were included. Quality assessment was completed using MINORS assessment. Articles were stratified into unrepaired and repaired capsule cohorts (excluding periportal capsulotomy techniques).

RESULTS

Eight articles were included. MINORS assessment ranged from 11-22, with excellent (k=0.842) inter-rater reliability. Populations without capsular repair were identified in four studies including a total of 387 patients, at an age of 33.1-38.0 years and follow-up range of 60.0-77 months. Populations with capsular repair were identified in five studies including a total of 835 patients, at an age range of 33.6-43.1 years and follow-up range of 60.0-78.0 months. All studies included PROs and all reported significant improvement (p<0.05) at the 5-year timepoint, with modified Harris Hip Score (mHHS) being the most frequent (n=6). No differences were noted between groups regarding any of the measured PROs. Average rates of achieving MCID and PASS for mHHS were similar between patients without capsular repair (MCID 71.1%, PASS 73.7%, n=1) and with capsular repair (MCID 66.0%-90.6%, PASS 55.3%-87.4%, n=4). Conversion to THA occurred in 12.8-18.5% and 0.0-29.0% for patients with an unrepaired and repaired capsule, respectively. Revision HA occurred in 15.4-25.5% and 3.1-15.4% in unrepaired and repaired capsular patients, respectively.

CONCLUSIONS

Patients undergoing hip arthroscopy for FAI had significant improvement in PRO scores at minimum 5-year follow-up, and scores did not differ between patients that underwent capsular repair and those that did not. Similar rates of markers of clinical benefit and THA conversion were achieved by both groups; however, lower rates of revision hip arthroscopy were demonstrated in the capsular repair cohort.

Comparison of Long-term Radiographic Outcomes and Rate and Time for Conversion to Total Knee Arthroplasty Between Repair and Meniscectomy for Medial Meniscus Posterior Root Tears: A Systematic Review and Meta-analysis

BACKGROUND

Previous meta-analyses have demonstrated superior outcomes in patients undergoing arthroscopic repair of medial meniscus posterior root tears (MMPRTs) compared with meniscectomy. However, these analyses have considered only short- or midterm outcomes and low-quality evidence.

PURPOSE

To compare the mid- to long-term rates of radiographic osteoarthritis (OA) between repair and meniscectomy for MMPRT.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

PubMed, EMBASE, Ovid/MEDLINE, and Cochrane Central Register of Controlled Trials databases were queried for articles evaluating repair and meniscectomy for MMPRT. Articles were eligible if they had a minimum mean 4-year follow-up for radiographic OA or conversion to total knee arthroplasty (TKA) and were at least level 3 evidence. Radiographic OA was assessed using Kellgren-Lawrence (KL) progression. Rates of conversion to TKA and International Knee Documentation Committee (IKDC) scores were also extracted. DerSimonian-Laird binary random-effects models were created to evaluate differences in radiographic OA and TKA conversion rates, with odds ratios (ORs) representing pooled estimates. Continuous random-effects models with standardized mean differences (SMDs) were used to compare postoperative IKDC scores.

RESULTS

Repair and meniscectomy cohorts were followed for a mean of 64.8 months and 62.5 months, respectively, for KL progression; and 82.8 months and 73.8 months, respectively, for TKA rates and IKDC scores. Overall, 59 of 144 (41%) patients undergoing surgical intervention for MMPRT demonstrated OA progression; 18 of 82 (22%) who underwent repair for MMPRT exhibited OA progression compared with 41 of 62 (66%) who underwent meniscectomy (OR, 0.17; 95% CI, 0.03-0.83; P = .029). Overall, 30 of 143 (21%) patients converted to TKA; 9.8% (8/82) of patients who underwent repair converted to TKA (range, 47-131 months), while 36% (22/61) who underwent meniscectomy converted to TKA (range, 17.8-101 months) (OR, 0.15; 95% CI, 0.05-0.44; P < .001). No significant differences between postoperative IKDC scores were observed (SMD, 0.51; 95% CI, -0.02 to 1.05; P = .06).

CONCLUSION

Medial meniscus posterior root repair results in significantly lower rates of radiographic OA progression and conversion to TKA at >60-month follow-up. On the basis of these findings, we recommend consideration of repair of MMPRTs when degenerative changes are not severe, as it can yield improved outcomes.

Return to Sport Following Distal Triceps Repair

PURPOSE

The purpose of this investigation was to examine the timeline of return-to-sport following distal triceps repair; evaluate the degree of participation and function upon returning to sport; and identify risk factors for failure to return to sport.

METHODS

Patients who underwent distal triceps repair with a minimum of 1 year of follow-up were retrospectively reviewed. Patients completed a subjective sports questionnaire and were scored on a visual analog scale for pain; the Mayo Elbow Performance Index; the Quick Disabilities of the Arm, Shoulder, and Hand; and the Single Assessment Numerical Evaluation.

RESULTS

Out of 113 eligible patients who had a distal triceps repair, 81 patients (71.7%) were contacted. Sixty-eight patients (84.0%) who participated in sports prior to surgery were included at 6.0 ± 4.0 years after surgery, and the average age was 46.6 ± 11.5 years. Sixty-one patients (89.7%) resumed playing at least 1 sport by 5.9 ± 4.4 months following distal triceps repair. However, 18 patients (29.5%) returned to a lower level of activity intensity. The average postoperative Quick Disabilities of the Arm, Shoulder, and Hand; Mayo Elbow Performance; visual analog scale for pain; and Single Assessment Numerical Evaluation scores were 8.2 ± 14.0, 89.5 ± 13.4, 2.0 ± 1.7, and 82.2 ± 24.3, respectively. No patients underwent revision surgery at the time of final follow-up.

CONCLUSIONS

Distal triceps repair enables 89.7% of patients to return to sport by 5.9 ± 4.4 months following surgery. However, 29.5% of patients were unable to return to their preinjury level of activity. It is imperative that patients are appropriately educated to manage postoperative expectations regarding sport participation following distal triceps repair.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Contemporary Principles for Postoperative Rehabilitation and Return to Sport for Athletes Undergoing Anterior Cruciate Ligament Reconstruction

Despite advancements in our understanding of anterior cruciate ligament (ACL) injury prevention and nonsurgical management, ACL reconstruction continues to occur at an alarming rate. Among athletic patients, individuals participating in basketball, soccer, and football have the highest incidence of ACL injury, often requiring surgical intervention. To ensure the optimal treatment strategy for return to sport and prevention of secondary graft re-tear, it is important to tailor to the specific demands of the injured athlete and apply evidence-based best practices and rehabilitation principles. The purpose of this review is to provide readers with a brief background regarding ACL injuries, a focused review of clinical outcome studies after ACL reconstruction, and an updated framework with expert-guided recommendations for postoperative rehabilitation and return to sporting activity. Currently, there is no gold standard for rehabilitation after ACL reconstruction, highlighting the need for robust studies evaluating the best modalities for athlete rehabilitation, as well as determining the efficacy of new tools for improving therapy including blood flow restriction therapy and neuromuscular electrical stimulation. Based on clinical experience, a renewed focus on objective, criteria-based milestones may maximize the ability of return to preinjury levels of athletic function.

Prolonged Postoperative Opioid Use After Arthroscopic Femoroacetabular Impingement Syndrome Surgery: Predictors and Outcomes at Minimum 2-Year Follow-up

Background:

The association between prolonged postoperative opioid use on outcomes after hip preservation surgery is not known.

Purpose:

To compare minimum 2-year patient-reported outcomes (PROs) between patients who required ≥1 postoperative opioid refill after undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS) versus patients who did not require a refill and to identify preoperative predictors for patients requiring ≥1 postoperative opioid refill.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Data from consecutive patients who underwent arthroscopic surgery for FAIS between January 2012 and January 2017 were analyzed. Multivariate regression analysis was performed to classify patient and radiographic variables as predictive of requiring ≥1 opioid prescription refill after surgery. Patients completed the following PROs preoperatively and at 2-year follow-up: Hip Outcome Score— Activities of Daily Living subscale (HOS-ADL), HOS–Sports Subscale (HOS-SS), modified Harris Hip Score (mHHS), International Hip Outcome Tool (iHOT-12), and 100-point visual analog scale (VAS) for pain and satisfaction. Scores were compared between patients needing additional prescription opioids and those who did not.

Results:

A total of 775 patients, of whom 141 (18.2%) required ≥1 opioid prescription refill, were included in the analysis. Patients requiring opioid refills had significantly lower 2-year postoperative PRO scores compared with patients not requiring refills: HOS-ADL (79.9 ± 20.3 vs 88.7 ± 14.9), HOS-SS (64.6 ± 29.5 vs 78.2 ± 23.7), mHHS (74.2 ± 21.1 vs 83.6 ± 15.9), iHOT-12 (63.6 ± 27.9 vs 74.9 ± 24.8), and VAS satisfaction (73.4 ± 30.3 vs 82.2 ± 24.9), as well as significantly more pain (26.8 ± 23.4 vs 17.9 ± 21.8) (P ≤ .001 for all). Predictors of requiring a postoperative opioid refill included patients with active preoperative opioid use (odds ratio, 3.12 [95% confidence interval, 1.06-9.21]; P = .039) and larger preoperative alpha angles (odds ratio, 1.04 [95% confidence interval, 1.01-1.07]; P = .03).

Conclusion:

Patients requiring ≥1 opioid prescription refill after hip arthroscopy for FAIS had lower preoperative and 2-year PRO scores when compared with patients not requiring refills. Additionally, active opioid use at the time of surgery was found to be predictive of requiring additional opioids for pain management.

Complete Capsular Closure Provides Higher Rates of Clinically Significant Outcome Improvement and Higher Survivorship Versus Partial Closure After Hip Arthroscopy at Minimum 5-Year Follow-Up

PURPOSE

To (1) compare the rates of reaching threshold hip-specific outcome scores for achieving the minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) in patients who underwent partial versus complete T-capsulotomy repair and (2) identify the failure rates in each group 5 years after undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS).

METHODS

Data from consecutive patients who underwent hip arthroscopy for FAIS performed by a single fellowship-trained surgeon from January 2011 to March 2013 were collected and analyzed. Baseline data, hip-specific outcomes, and clinical failure rates were recorded at a minimum of 5 years postoperatively. Patients with partial T-capsulotomy repair were matched 1:3 by age, body mass index, and sex to patients with complete T-capsulotomy repair. Threshold scores for achieving the MCID and PASS were calculated and compared between the 2 groups. Additionally, rates of revision and conversion to total hip arthroplasty (THA) were compared between the groups.

RESULTS

A total of 379 patients were available for analysis (39 partial and 340 complete repairs), with 100 patients included in the matching process (25 in the partial-repair group and 75 in the complete-repair group). Comparison of radiographic parameters, including the Tönnis grade, alpha angle, and lateral center-edge angle, between the 2 groups showed no statistically significant difference (P > .05 for all). Comparison of postoperative score averages between the partial- and complete-closure groups showed a significant difference in the Hip Outcome Score-Activities of Daily Living Subscale (85.4 ± 17.7 vs 94.6 ± 7.8, P < .001), Hip Outcome Score-Sports Subscale (76.6 ± 26.2 vs 89.3 ± 16.8, P = .034), modified Harris Hip Score (83.2 ± 19.7 vs 90.5 ± 11.2, P = .035), and visual analog scale pain score (24.5 ± 30.8 vs 13.4 ± 15.8, P = .035). A total of 65 complete-repair patients (95.6%) achieved the MCID for at least 1 outcome measure versus 18 patients with partial repair (78.3%) (P = .04). A total of 69 complete-repair patients (92%) achieved the PASS for at least 1 outcome measure versus 18 partial-repair patients (72%) (P = .017). Of the 39 partial-repair patients, 35.9% (n = 14) underwent revision or conversion to THA, as compared with 2.9% (n = 10) in the overall cohort.

CONCLUSIONS

At a minimum 5-year follow-up, patients with complete capsular closure after hip arthroscopy for FAIS show superior long-term outcomes and achieve higher rates of meaningful clinical success when compared with patients with partial capsular closure. Furthermore, patients with partial capsular repair undergo revision or conversion to THA at high rates.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Hip Arthroscopy for Femoroacetabular Impingement Syndrome in Adolescents Provides Clinically Significant Outcome Benefit at Minimum 5-Year Follow-Up

PURPOSE

To report the rates of achieving clinically significant outcomes as defined by the minimal clinically important difference (MCID), patient acceptable symptomatic state (PASS), or substantial clinical benefit (SCB) in adolescent patients and the rates of clinical failure 5 years after undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS).

METHODS

Data from consecutive adolescent patients (defined by the American Academy of Pediatrics as age 11 to 21 years) who underwent primary hip arthroscopy with routine capsular closure for the treatment of FAIS between January 2012 and January 2015 by a single, fellowship-trained surgeon was collected. Baseline data, clinical outcomes including Hip Outcome Score (HOS)-Activities of Daily Living, HOS-Sports Subscale, modified Harris hip score, international Hip Outcome Tool, and clinical failure rates were recorded at 5 years after operative. Clinical failure was defined by revision hip arthroscopy or conversion to total hip arthroplasty. Clinically significant outcomes was defined as achieving MCID, PASS, or SCB on at least 1 hip-specific outcome measure.

RESULTS

Of the 139 eligible patients, a total of 85 (60.4%) patients (85 hips) were included in the final analysis, with an age and body mass index average of 17.6 ± 2.5 years (range 13-21) and 22.3 ± 3.1 kg/m², respectively. The majority of the patients were female (80.6%) and participated in sports (76.2%). There was statistically significant difference between preoperative and postoperative score averages across every reported outcome (P < .001). At 5 years, 88.4%, 67.6%, and 64.9% reached at least 1 threshold for achieving MCID, PASS, and SCB, respectively, whereas 89.2% achieved at least one of the meaningful outcome thresholds. Last, 2 patients (2.4%) failed clinically, with both undergoing revision (2.4%) because of continued pain. There were no conversions to total hip arthroplasty.

CONCLUSION

This study demonstrated that a large majority (89.2%) of adolescent patients undergoing primary arthroscopic treatment for symptomatic FAIS achieved meaningful clinically significant outcomes. Furthermore, only 2.4% of patients failed clinically, requiring revision hip arthroscopy because of continued pain.

LEVEL OF EVIDENCE

IV, Retrospective Case Series.

Return to work following distal triceps repair

PURPOSE

The purpose of this study was to evaluate the rate and duration of return to work in patients undergoing distal triceps repair (DTR).

METHODS

Consecutive patients undergoing DTR from 2009 to 2017 at our institution were retrospectively reviewed at a minimum of 1 year postoperatively. Patients completed a standardized and validated work questionnaire; a visual analog scale for pain; the Mayo Elbow Performance Score; the short version of the Disabilities of the Arm, Shoulder and Hand questionnaire; and a satisfaction survey.

RESULTS

Of 113 eligible patients who underwent DTR, 81 (71.7%) were contacted. Of these patients, 74 (91.4%) were employed within 3 years prior to surgery (mean age, 46.0 ± 10.7 years; mean follow-up, 5.9 ± 3.9 years). Sixty-nine patients (93.2%) returned to work by 2.2 ± 3.2 months postoperatively. Sixty-six patients (89.2%) were able to return to the same level of occupational intensity. Patients who held sedentary-, light-, medium-, and high-intensity occupations were able to return to work at a rate of 100.0%, 100.0%, 80.0%, and 76.9%, respectively, by 0.3 ± 0.5 months, 1.8 ± 1.5 months, 2.5 ± 3.6 months, and 4.8 ± 3.9 months, respectively, postoperatively. Of the workers' compensation patients, 15 (75%) returned to work by 6.5 ± 4.3 months postoperatively, whereas 100% of non-workers' compensation patients returned to work by 1.1 ± 1.6 months (P < .001). Seventy-one patients (95.9%) were at least somewhat satisfied, with 50 patients (67.6%) reporting excellent satisfaction. Seventy-two patients (97.3%) would undergo the operation again if presented the opportunity. A single patient (1.4%) required revision DTR.

CONCLUSIONS

Approximately 93% of patients who underwent DTR returned to work by 2.2 ± 3.2 months postoperatively. Patients with higher-intensity occupations had an equivalent rate of return to work but took longer to return to their preoperative level of occupational intensity. Information regarding return to work is imperative in preoperative patient consultation to manage expectations.

Knockout of the gene encoding the extracellular matrix protein SNED1 results in early neonatal lethality and craniofacial malformations

BACKGROUND

The extracellular matrix (ECM) is a fundamental component of multicellular organisms that orchestrates developmental processes and controls cell and tissue organization. We previously identified the novel ECM protein SNED1 as a promoter of breast cancer metastasis and showed that its level of expression negatively correlated with breast cancer patient survival. Here, we sought to identify the roles of SNED1 during murine development.

RESULTS

We generated two novel Sned1 knockout mouse strains and showed that Sned1 is essential since homozygous ablation of the gene led to early neonatal lethality. Phenotypic analysis of the surviving knockout mice revealed a role for SNED1 in the development of craniofacial and skeletal structures since Sned1 knockout resulted in growth defects, nasal cavity occlusion, and craniofacial malformations. Sned1 is widely expressed in embryos, notably by cell populations undergoing epithelial-to-mesenchymal transition, such as the neural crest cells. We further show that mice with a neural-crest-cell-specific deletion of Sned1 survive, but display facial anomalies partly phenocopying the global knockout mice.

CONCLUSIONS

Our results demonstrate requisite roles for SNED1 during development and neonatal survival. Importantly, the deletion of 2q37.3 in humans, a region that includes the SNED1 locus, has been associated with facial dysmorphism and short stature.

Patients With Borderline Hip Dysplasia Achieve Clinically Significant Improvement After Arthroscopic Femoroacetabular Impingement Surgery: A Case-Control Study With a Minimum 5-Year Follow-up

BACKGROUND

Hip arthroscopy for the treatment of femoroacetabular impingement syndrome (FAIS) in patients with borderline hip dysplasia (BHD) is becoming a more common practice. However, the literature on achieving meaningful outcomes at midterm follow-up, as well as predictors of these outcomes, is limited.

PURPOSE

To (1) compare the rates of achieving meaningful clinical outcomes between patients with and without BHD and (2) identify the predictors for achieving clinical success among patients with BHD 5 years after undergoing hip arthroscopic surgery for FAIS.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data from consecutive patients who underwent primary hip arthroscopic surgery with routine capsular closure for the treatment of FAIS between January 2012 and August 2014 were collected and retrospectively analyzed. Patients with BHD (lateral center-edge angle [LCEA] 20°-25°) were matched 1:2 by age (±1 year) and body mass index (BMI; ±5 kg/m²) to control patients with normal acetabular coverage (LCEA 25°-40°). Data collected included baseline and 5-year postoperative patient-reported outcomes. The minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) were calculated for each patient-reported outcome measure and compared between the 2 groups. A binary logistic regression analysis was used to identify significant predictors of achieving the MCID and PASS in the BHD group.

RESULTS

The MCID in the BHD group was defined as 9.6, 14.1, and 9.5 for the Hip Outcome Score-Activities of Daily Living, Hip Outcome Score-Sports Subscale, and modified Harris Hip Score, respectively. Threshold scores for achieving the PASS in both groups were 90.9, 76.6, and 81.9, respectively. A total of 88 patients were identified with having BHD and were matched to 176 controls. No statistical differences were identified for age, BMI, or sex. Both the BHD and the non-BHD groups had statistically significant increases in patient-reported outcome scores over the 5-year period, but the difference in both groups was not statistically significant (P > .05 for all). There was no statistical difference in the frequency of patients in the BHD and non-BHD groups achieving the MCID (86.6% vs 85.2%, respectively; P = .804) or PASS (76.0% vs 73.7%, respectively; P = .675) on at least 1 outcome measure. The logistic regression model demonstrated that being physically active (odds ratio [OR], 27.59; P = .005) and being female (OR, 14.64; P = .025) were independent predictors of achieving the MCID, while running (OR, 11.1; P = .002), being female (OR, 7.6; P = .011), and a larger preoperative LCEA (OR, 2.3; P = .001) were independent preoperative predictors of achieving the PASS.

CONCLUSION

The rates of achieving clinical success 5 years after undergoing arthroscopic treatment with capsular closure for FAIS were not significantly different between patients with BHD and those with normal acetabular coverage. Being physically active, running for exercise, female sex, and a larger LCEA were preoperative predictors of achieving clinical success at 5 years in patients with BHD.

The Effect of Postoperative Opioid Prescription Refills on Achieving Meaningful Clinical Outcomes After Hip Arthroscopy for Femoroacetabular Impingement Syndrome

PURPOSE

To determine whether requiring postoperative opioid refills has an effect on both baseline and postoperative functional scores, as well as rates of achieving clinical success 2 years after hip arthroscopy for femoroacetabular impingement syndrome (FAIS).

METHODS

Data from consecutive patients undergoing hip arthroscopy for FAIS from January 2012 to December 2016 were analyzed. Patients with at least 1 postoperative opioid refill were matched 1:2 by age and body mass index to patients not requiring refills. Preoperative and postoperative patient-reported outcomes including the Hip Outcome Score-Activities of Daily Living Subscale, HOS-Sports Subscale, and modified Hip Harris Score, as well as visual analog scale (VAS) pain and satisfaction surveys, were compared between the 2 groups, as well as between patients who requested 1 refill versus those requiring 2 or more refills. The minimal clinically important difference and patient acceptable symptomatic state (PASS) were calculated for the study group and compared between patient groups.

RESULTS

A total of 128 patients (14.5%) requesting at least 1 postoperative opioid refill and 256 with no refills were included in the study. Analysis showed that the refill group had lower patient-reported outcomes (P < .05 for all), a lower VAS satisfaction score average (73.2 ± 30.7 vs 80.1 ± 25.9, P = .029), and a higher VAS pain score average (27.2 ± 26.1 vs 19.9 ± 22.7, P = .007). Similar trends were seen when patients with 1 refill were compared with those with 2 or more refills. Analysis of meaningful clinical outcomes showed that patients in the refill group had lower rates of achieving the PASS (68.3% vs 77.2%, P = .006). However, there were no statistically significant differences in achieving the minimal clinically important difference between the 2 groups (P > .05 for all).

CONCLUSIONS

Patients undergoing hip arthroscopy for FAIS who require 1 or more opioid refills postoperatively are likely to have lower baseline and postoperative functional scores, as well as to achieve the PASS at lower rates, compared with patients who do not require an additional opioid prescription to what is routinely given after surgery.

LEVEL OF EVIDENCE

Level III, retrospective case-control study.

Preoperative Hip Extension Strength Is an Independent Predictor of Achieving Clinically Significant Outcomes After Hip Arthroscopy for Femoroacetabular Impingement Syndrome

BACKGROUND

The effect of preoperative hip strength on outcomes after hip arthroscopy for femoroacetabular impingement syndrome (FAIS) is unclear. The purpose of this study was to determine whether preoperative isometric hip strength is associated with outcome scores at 6 months as well as achieving the minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) in patients undergoing hip arthroscopy for FAIS.

HYPOTHESIS

Increased preoperative isometric strength will be correlated with short-term postoperative outcomes and will be predictive of achieving higher functional status.

STUDY DESIGN

Case series.

LEVEL OF EVIDENCE

Level 4.

METHODS

Data from 92 consecutive patients undergoing primary hip arthroscopy for treatment of FAIS from March through August 2018 were analyzed. All patients included in the analysis had preoperative measures of isometric hip strength on both affected and unaffected limbs, as well as preoperative and 6-month patient-reported outcome (PRO) scores. Analysis was performed to determine correlations between normalized isometric hip strength measurements and PROs and whether strength measurements were predictive of achieving MCID or PASS.

RESULTS

A total of 74 (80.4%) patients had 6-month PROs and were included in the final analysis. Hip extension strength on both sides was correlated with all postoperative PROs (all P > 0.05). Abduction strength on both sides was correlated with postoperative Hip Outcome Score-Activities of Daily Living subscale score, achieving MCID on at least 1 score threshold, and reaching the international Hip Outcome Tool-12 threshold score for achieving PASS (all P < 0.05). Regression analysis showed that extension strength on the affected side was the only strength measurement predictor of achieving PASS (1.043; P = 0.049).

CONCLUSION

Preoperative isometric hip extension and abduction strength are correlated with 6-month postoperative PRO scores. Furthermore, hip extension strength is a predictor of achieving clinically meaningful outcomes.

CLINICAL RELEVANCE

This study highlights the possible importance of preoperative optimization of hip function to maximize outcomes in patients undergoing hip arthroscopy for FAIS.

Defining Meaningful Functional Improvement on the Visual Analog Scale for Satisfaction at 2 Years After Hip Arthroscopy for Femoroacetabular Impingement Syndrome

PURPOSE

To (1) define Substantial Clinical Benefit (SCB), Patient Acceptable Symptomatic State (PASS), and Minimal Clinically Important Difference (MCID) for the visual analog scale (VAS) Satisfaction in patients undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS), and (2) identify preoperative predictors of achieving each outcome end-point.

METHODS

Data from consecutive patients who underwent primary hip arthroscopy between November 2014 and January 2017 were prospectively collected and retrospectively analyzed. Inclusion criteria consisted of patients with clinical and radiographic diagnosis of FAIS, who failed nonoperative treatment, underwent primary hip arthroscopy to address the FAIS, and had at minimum 2-year follow-up. Baseline data and postoperative patient-reported outcome scores were recorded at 2 years postoperatively. To quantify clinical significance of outcome achievement on the VAS)Satisfaction, we calculated MCID, PASS, and SCB for this outcome measure. A multivariate logistic regression analysis was used to identify preoperative predictors of achieving SCB, PASS, and MCID satisfaction.

RESULTS

A total of 335 patients were included in the final analysis, with an average age and body mass index (BMI) of 32.8 (standard deviation ± 12.4) years and 25.2 (standard deviation ± 5.3), respectively, and the majority being female (69.3%). The values on the VAS satisfaction were identified to represent MCID, PASS, and SCB, respectively: 52.8, 80.9, and 89.7. The rates of achieving clinically significant improvement on the VAS Satisfaction was 85.6%, 68.1%, and 56.9% for MCID, PASS, and SCB, respectively. A larger preoperative alpha angle was predictive for achieving SCB (odds ratio [OR], 1.076; P = .046), whereas lower BMI (OR, 0.955; P = .047) and larger preoperative alpha angle (OR, 1.12; P = .025) were predictors for achieving PASS.

CONCLUSIONS

This study identified threshold VAS satisfaction scores of 52.8, 80.9, and 89.7 for achieving MCID, SCB, and PASS, respectively, at 2-year follow-up following hip arthroscopy for FAIS. Furthermore, preoperative variables including larger preoperative alpha angles and lower BMI are predictors of achieving superior clinical satisfaction.

LEVEL OF EVIDENCE

Level IV, Case Series.

Squat and gait biomechanics 6 months following hip arthroscopy for femoroacetabular impingement syndrome

The purpose of this study was to (i) assess whether squat and gait biomechanical measures improve in patients with femoroacetabular impingement syndrome (FAIS) 6 months after surgery compared to pre-operative measures and (ii) compare biomechanical properties to controls without FAIS. In this prospective study, biomechanical data during a double leg squat task and gait for 15 FAIS patients and 9 controls were collected using three-dimensional motion analysis. Data were collected in the FAIS group at two-time points, pre-operatively and 6-month post-operatively following arthroscopic hip surgery, and at a single time point for the healthy controls. Independent sample's t-test were used to compare the FAIS group to the controls, and paired samples t-test were used to determine within-group differences before and after hip arthroscopy in the FAIS group. The results indicated that there were significant within-group increases for sagittal plane moment rate during the double leg squat task (P = 0.009) between the pre-operative and post-operative time points for the FAIS group. Between-group differences showed that FAIS patients pre-operatively exhibit slower squat velocities during the descent (P = 0.005) and ascent phase (P = 0.012) of a double leg squat when compared healthy controls. Reduced hip external rotation moments during gait (P = 0.02) were also found between FAIS patients pre-operatively and controls. In conclusion, alterations in hip biomechanics are present before surgery for FAIS when compared to healthy controls, and joint mechanics change 6 months after surgery. However, the biomechanical differences during a double leg squat and gait were minimal.

Comparing Outcomes of Competitive Athletes Versus Nonathletes Undergoing Hip Arthroscopy for Treatment of Femoroacetabular Impingement Syndrome

BACKGROUND

A growing number of studies have examined return to sport in competitive athletes after undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS); however, few have evaluated the rate of achieving meaningful clinical outcomes in this group.

PURPOSE

To determine if competitive athletes (professional, semiprofessional, or collegiate) have better 2-year patient-reported outcomes and achieve the minimal clinically important difference (MCID) and substantial clinical benefit at higher rates when compared with nonathletes undergoing hip arthroscopy for the treatment of FAIS.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

The study was a retrospective analysis of all consecutive patients who identified as either a competitive athlete or a nonathlete and had undergone hip arthroscopy for FAIS by a single fellowship-trained surgeon between January 2012 and April 2017. Patients in the 2 groups were matched 1:2 by age, sex, and body mass index. Baseline and clinical outcomes, including the Hip Outcome Score-Activities of Daily Living, Hip Outcome Score-Sports Subscale (HOS-SS), modified Harris Hip Score, and international Hip Outcome Tool-12, were collected preoperatively and at 2 years postoperatively and compared between the groups. The MCID and substantial clinical benefit were calculated for each group separately and compared using chi-square analysis.

RESULTS

A total of 59 competitive athletes and 118 nonathletes were included in the final analysis. Most of the competitive athletes were soccer players (23.7%), followed by softball players (10.2%) and runners (10.2%). Postoperative score comparison between competitive athletes and nonathletes demonstrated a statistically significant difference in the HOS-SS (mean ± SD, 84.5 ± 19.0 vs 76.1 ± 23.8; P = .02). Meaningful outcome analysis demonstrated that competitive athletes had a higher rate of achieving the HOS-SS threshold for the MCID (97.4% vs 82.5%; P = .021). There was no other difference in frequency of achieving the threshold for any other meaningful clinical outcome between the groups.

CONCLUSION

Hip arthroscopy for the treatment of FAIS in competitive athletes and nonathletes produced clinically meaningful outcomes in both patient groups. However, competitive athletes achieved the MCID on the HOS-SS at higher rates than nonathletes and had significantly higher scores at 2 years postoperatively on the HOS-SS.

Patients With Borderline Hip Dysplasia Achieve Clinically Significant Outcome After Arthroscopic Femoroacetabular Impingement Surgery: A Case-Control Study With Minimum 2-Year Follow-up

BACKGROUND

There is a growing trend for hip arthroscopists to treat patients with borderline hip dysplasia (BHD) for femoroacetabular impingement syndrome (FAIS) without addressing the acetabular coverage. However, the literature of outcomes and failure rates for these patients is conflicting.

PURPOSE

(1) To identify whether patients with BHD achieved 2-year similar patient-reported outcome, minimal clinically important difference (MCID), and patient acceptable symptomatic state (PASS) when compared with patients without BHD and (2) to identify predictors for achieving the MCID and PASS among patients with BHD who are undergoing hip arthroscopy for FAIS.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data from consecutive patients who underwent primary hip arthroscopy with routine capsular closure for the treatment of FAIS between January 2012 and January 2017 were collected and retrospectively analyzed. Patients with BHD (lateral center-edge angle [LCEA], 20°-25°) were matched 2:1 by age, sex, and body mass index (BMI) to control patients with normal acetabular coverage (LCEA, >25°-40°). Patient-reported outcome, MCID, and PASS were compared between the groups. Multivariate logistic regression analysis identified significant predictors of achieving the MCID and PASS in the BHD group.

RESULTS

The MCID in the BHD group was defined as 9.2, 13.7, 8.5, and 15.2 for the Hip Outcome Score-Activities of Daily Living, Hip Outcome Score-Sport Specific, modified Harris Hip Score, and iHOT-12, respectively. Threshold scores for achieving the PASS in both groups were 87.9, 76.4, 78.1, and 60.0. A total of 112 patients were identified as having BHD (LCEA, 20°-25°) and were matched to 224 controls. Both groups saw statistically significant increases in score averages over the 2-year period; however, the differences between them were not statistically significant (P > .05 for all). There was no statistical difference in the frequency of the BHD and non-BHD cohorts achieving the MCID on at least 1 threshold score (86.6% vs 85.6%, P = .837) and the PASS (78.6% vs 79.8%, P = .79). There was, however, a statistically significant difference between the rates of patients with and without BHD achieving the PASS on the modified Harris Hip Score threshold (62.5% vs 74.5%, P = .028). The final logistic models demonstrated that lower BMI (odds ratio [OR], 0.872; P = .029), lower preoperative alpha angle (OR, 0.965; P = .014), and female sex (OR, 3.647; P = .03) are independent preoperative predictors of achieving the MCID, while lower preoperative alpha angle (OR, 0.943; P = .018) and self-reported limp (OR, 18.53; P = .007) are independent preoperative predictors of achieving the PASS.

CONCLUSION

Outcome improvements in patients with BHD who are undergoing arthroscopic treatment with capsular closure for FAIS are not significantly different from patients with normal acetabular coverage. Lower BMI, lower alpha angle, absence of limp, and female sex are preoperative predictors of achieving meaningful clinically significant outcome improvements in patients with BHD.

Diagnostic validity of the dementia questionnaire for Alzheimer disease

OBJECTIVE

To determine the sensitivity and specificity of postmortem dementia diagnoses based on a retrospective informant interview by comparison with criterion standard neuropathological diagnoses and the results of previous clinical examinations.

SETTING

Three university-based academic research centers.

SUBJECTS

Fifty-four deceased elderly persons with Alzheimer disease, another dementing disorder, a neurologic disease resulting in functional impairment but no dementia, or no neurologic disorder.

METHODS

Blinded nonclinician interviewers administered the Dementia Questionnaire (DQ) by telephone to informants, typically close relatives, who were familiar with the intellectual and functional status of the subjects before death. Two senior clinicians (LJ.T. and C.K.) rated each DQ for the presence or absence of a dementia syndrome during life and for the specific disorders causing the dementia, if present. Raters were blinded to the neuropathological findings and based their assessments only on data provided by responses to the DQ. Comparison was made with diagnoses based on neuropathological assessment. In most cases, the results of antemortem clinical examinations were also available as a check on the clinical diagnosis of the dementia syndrome. Sensitivity and specificity of the DQ diagnoses were computed, and chance-corrected agreement measures were calculated for the 2 independent DQ raters (LJ.T. and C.K.).

RESULTS

Compared with antemortem clinical diagnosis, the average sensitivity of the DQ for the clinical syndrome of dementia was 92.8%, the specificity was 89.5%, and the interrater agreement was 98% (kappa = 0.96). Among 7 subjects with mild dementia (Mini-Mental State Examination score > or = 24 at the last clinical examination), 5 (71%) were correctly identified using the DQ. The DQ correctly indicated the absence of dementia in 8 (80%) of 10 subjects with other neurologic disorders causing functional impairment. Compared with the neuropathological diagnoses, the DQ differentiated Alzheimer disease from other primary causes of dementia with a sensitivity of 89% and a specificity of 72%. The interrater agreement was 93.8% (kappa = 0.85).

CONCLUSIONS

Compared with the results of the antemortem clinical examinations, the DQ was sensitive to the presence of dementia, detected most cases of mild dementia, and discriminated dementia from other neurologic disorders causing functional impairment. Compared with the neuropathological diagnoses, the ability of the DQ to differentiate Alzheimer disease from other dementing disorders indicates that it may be useful as a research tool.

Identification of the MN/CA9 protein as a reliable diagnostic biomarker of clear cell carcinoma of the kidney

The MN/CA9 protein is a tumor-associated antigen that has been shown to have diagnostic utility in identifying cervical dysplasia and carcinoma. MN/CA9 expression is limited to very few normal tissues. We have now extended those observations to further investigate expression of the MN/CA9 protein in histological sections and fine-needle aspiration biopsy smears of normal kidney, benign renal cell lesions, all categories of renal cell carcinomas (clear/granular/spindle cell, chromophilic cell, chromophobic cell, and collecting duct cell RCCs), metastatic RCCs, and non-renal cell clear cell adenocarcinomas. We have found that high levels of MN/CA9 expression is seen in all primary RCCs, cystic RCCs, and metastatic RCCs, with the exception of two cases of the chromophobe cell type, which were MN/CA9 negative. Identical MN/CA9 immunostaining was also observed in the aspiration cytological smears. In contrast, all benign lesions, including pyelonephritis, renal cysts, adenomas, oncocytomas, and normal kidney, did not express the MN/CA9 protein. Thus, we conclude that MN/CA9 protein expression could serve as a valuable adjunct to the cytological and histological diagnosis of benign renal cysts versus cystic RCC, adenoma versus RCC, and oncocytoma versus granular cell RCC. Diffuse membraneous staining of all RCCs (with the exception of chromophobic cell RCC) suggests that MN/CA9 protein expression might have an important clinical utility in the early detection and treatment of RCC. Absence of MN/CA9 expression in non-renal cell clear cell adenocarcinoma also indicates that MN/CA9 protein expression may be used as a differential diagnostic biomarker of metastatic clear cell RCC.

Effects of transfusion on rheological properties of blood in sickle cell anemia

The effects of transfusion on the rheological properties of blood in sickle cell anemia were studied in 15 patients. Blood samples were obtained before and after transfusion of normal (hemoglobin AA) packed cells. Blood viscosity was determined with a coaxial cylinder viscometer over a wide range of shear rates. The index of oxygen dependence of blood viscosity (eta O2) was calculated as the ratio of viscosity values at low PO2 (20 mm Hg) and at high PO2 (100 mm Hg) levels. After transfusion, blood viscosity significantly increased as a result of an evaluation of hematocrit. Although transfusion of normal cells into sickle cell anemia patients results in an increased oxygen content of blood and a decreased oxygen dependence of blood viscosity, an elevation of hematocrit value beyond 35 per cent may cause a high viscosity state and outweigh the benefits of transfusion. Judicious monitoring of blood viscosity should serve as a guide for blood transfusion in these patients.

The use of radioactive isotopes for analysis of cutaneous allergic responses

Local exudation at the sites of allergic and histamine-induced cutaneous reactions, was measured with an in vivo double-labelling procedure, based upon local serial simultaneous measurements of indium-113 m (113mIn) labelled transferrin and technitium-99m labeled red blood cells (99mTc RBC). Analyses depended upon the reaction index i.e. comparison of the ratio of 113mIn/99mTc counts at the reaction site with the ratio of 113mIn/99mTc at the corresponding unreacted site in the skin of the opposite arm. Reaction indices were initially significantly elevated at the sites of histamine and allergic reactions. After the first hour, there was a progressive reduction at histamine sites indicating a tapering of the local accumulation of indium-labelled transferrin. By contrast allergic reaction sites showed a continuing increase in the reaction index after one hour. During the first hour the curves were comparable, but they diverge and were significantly different after one hour (0.05 greater than P greater than 0.02). This is consistent with the known occurrence of late cutaneous reponses at the site of allergic but not histamine reactions.