Christopher M Larson

Minnesota Orthopedic Sports Medicine Institute at Twin Cities Orthopedics, Edina, Minnesota, United States

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Publications (51)127.62 Total impact

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    ABSTRACT: This study aimed to characterize the radiographic deformity observed in a consecutive series of butterfly goalies with symptomatic mechanical hip pain and to use computer-based software analysis to identify the location of impingement and terminal range of motion. We also compared these analyses to a matched group of positional hockey players with symptomatic femoroacetabular impingement (FAI). A consecutive series of 68 hips in 44 butterfly-style hockey goalies and a matched group of 34 hips in 26 positional hockey players who underwent arthroscopic correction for symptomatic FAI were retrospectively analyzed. Each patient underwent preoperative anteroposterior (AP) and modified Dunn lateral radiographs and computed tomography (CT) of the affected hips. Common FAI measurements were assessed on plain radiographs. Patient-specific, CT-based 3-dimensional (3D) models of the hip joint were developed, and the femoral version, alpha angles at each radial clock face position, and femoral head coverage were calculated. Maximum hip flexion, abduction, internal rotation in 90° flexion (IRF), flexion/adduction/internal rotation (FADIR), and butterfly position were determined, and the areas of bony collision were defined. Butterfly goalies had an elevated mean alpha angle on both AP (61.3°) and lateral radiographs (63.4°) and a diminished beta angle (26.0°). The mean lateral center-edge angle (LCEA) measured 27.3° and acetabular inclination was 6.1°. A crossover sign was present in 59% of the hips. The maximum alpha angle on the radial reformatted computed tomographic scan was significantly higher among the butterfly goalies (80.9° v 68.6°; P < .0001) and was located in a more lateral position (1:00 o'clock v. 1:45 o'clock; P < .0001) compared with positional players. Symptomatic butterfly hockey goalies have a high prevalence of FAI, characterized by a unique femoral cam-type deformity and noted by an elevated alpha angle and loss of offset, which is greater in magnitude and more lateral when compared with that in positional hockey players. Associated acetabular dysplasia is also common among hockey goalies. Level IV, prognostic case series. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.
    12/2014;
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    ABSTRACT: Previous studies have reported residual deformity to be the most common reason for revision hip arthroscopy. An awareness of the most frequent locations of the residual deformities may be critical to minimize these failures. The purposes of this study were to (1) define the three-dimensional (3-D) morphology of hips with residual symptoms before revision femoroacetabular impingement (FAI) surgery; (2) determine the limitation in range of motion (ROM) in these patients using dynamic, computer-assisted, 3-D analysis; and (3) compare these measures with a cohort of patients who underwent successful arthroscopic surgery for FAI by a high-volume hip arthroscopist. Between 2008 and 2013, one senior surgeon (BTK) performed revision arthroscopic FAI procedures on patients with residual FAI deformity and symptoms after prior unsuccessful arthroscopic surgery; all of these 47 patients (50 hips) had preoperative CT scans. Mean patient age was 29 ± 9 years (range, 16-52 years). Three-dimensional models of the hips were created to allow measurements of femoral and acetabular morphology and ROM to bony impingement using a validated, computer-based dynamic imaging software. During the same time period, 65 patients with successful primary arthroscopic treatment of FAI by the same surgeon underwent preoperative CT scans for the symptomatic contralateral hip; this group of 65 patients thus fortuitously provided postoperative evaluation of the originally operated hip and served as a control group. A comparison of the virtual correction with the actual correction in the primary successful FAI treatment cohort was performed. Correspondingly, a comparison of the recommended virtual correction with the correction evident at the time of presentation after failed primary surgery in the revision cohort was performed. Analysis was performed by two independent observers (JRR, OA) and a paired t-test was used for comparison of continuous variables, whereas chi-square testing was used for categorical variables with p < 0.05 defined as significant. Ninety percent (45 of 50) of patients undergoing revision surgery for symptomatic FAI had residual deformities; the mean maximal alpha angle in revision hips was 68° ± 16° and was most often located at 1:15, considering the acetabulum as a clockface and 1 to 5 o'clock as anterior independent of side. Twenty-six percent (13 of 50) of hips had signs of overcoverage with a lateral center-edge angle greater than or equal to 40°. Dynamic analysis revealed mean direct hip flexion of 114° ± 11° to osseous impingement. Internal rotation in 90° of hip flexion and flexion, adduction, internal rotation to osseous contact were 28° ± 12° and 20° ± 10°, respectively, which were less than those in hips that had underwent hip arthroscopy by a high-volume hip arthroscopist (all p < 0.001). We found marked radiographic evidence of incomplete correction of deformity in patients with residual symptoms compared with patients with successful results with residual deformity present in the large majority of patients (45 of 50 [90%]) undergoing residual FAI surgery. We recommend careful attention to full 3-D resection of impinging structures. Level III, retrospective study, case series.
    Clinical Orthopaedics and Related Research 12/2014; · 2.79 Impact Factor
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    ABSTRACT: Plain radiographic measures of the acetabulum may fail to accurately define coverage or pathomorphology such as impingement or dysplasia. CT scans might provide more precise measurements for overcoverage and undercoverage. However, a well-defined method for such CT-based measurements and normative data regarding CT-based acetabular coverage is lacking. The purposes of the study were (1) to develop a method for evaluation of percent coverage of the femoral head by the acetabulum; and (2) to define normative data using a cohort of asymptomatic patient hip and pelvic CT scans and evaluate the variability in acetabular version for asymptomatic patients with normal lateral coverage (lateral center-edge angle [LCEA] 20°-40°) that has previously been defined as abnormal based on radiographic parameters. Two-hundred thirty-seven patients (474 hips) with hip CT scans obtained for reasons other than hip-related pain were evaluated. The scans were obtained from a hospital database of patients who underwent CT evaluation of abdominal trauma or pain. In addition, hips with obvious dysplasia (LCEA < 20°) or profunda (LCE > 40°) were excluded resulting in a final cohort of 222 patients (409 hips [115 men, 107 women]) with CT scans and a mean age of 25 ± 3 years. CT scan alignment was corrected along the horizontal and vertical axis and percent acetabular coverage around the clockface (3 o'clock = anterior), and regional (anterior, superior, posterior) and global surface area coverage was determined. Percent coverage laterally was correlated with the LCEA and the presence and prevalence of cranial retroversion (crossover sign) and a positive posterior wall sign were determined. The mean regional percent femoral head surface area coverage for the asymptomatic cohort was 40% ± 2% anteriorly, 61% ± 3% superiorly, and 48% ± 3% posteriorly. Mean global coverage of the femoral head was 40% ± 2%. The local coverage anteriorly (3 o'clock) was 38% ± 3%, laterally (12 o'clock) was 67% ± 2%, and posteriorly (9 o'clock) was 52% ± 3%. The mean lateral coverage represented a mean LCEA of 31° (± 1 SD). Fifteen percent of hips demonstrated cranial retroversion that would correlate with a crossover sign, and 30% had < 50% posterior coverage that would correlate with a positive posterior wall sign on an anteroposterior pelvis radiograph. In addition, male hips had a higher prevalence of a crossover sign (19%; 95% confidence interval [CI], 14%-25% versus 11%; 95% CI, 7%-16%; p = 0.03) and posterior wall sign (46%; 95% CI. 39%-53% versus 13%; 95% CI, 9%-19%; p < 0.001) compared with women. A positive crossover sign or posterior wall sign was present for 113 male hips (53%; 95% CI, 46%-60%) compared with 39 female hips (20%; 95% CI, 15%-26%; p < 0.001). This study provides normative coverage data and a reproducible method for evaluating acetabular coverage. Cranial acetabular retroversion (crossover sign) and a positive posterior wall sign were frequent findings in a young asymptomatic cohort and might be a normal variant rather than pathologic in a significant number of cases. Level III, diagnostic study.
    Clinical Orthopaedics and Related Research 11/2014; · 2.79 Impact Factor
  • Source
    Patrick A Massey, Shane J Nho, Christopher M Larson, Joshua D Harris
    Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society. 10/2014;
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    ABSTRACT: The current understanding of the effect of dynamic changes in pelvic tilt on the functional acetabular orientation and occurrence of femoroacetabular impingement (FAI) is limited.
    The American journal of sports medicine. 07/2014;
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    ABSTRACT: There are limited data reporting outcomes after revision arthroscopic surgery for residual femoroacetabular impingement (FAI).
    The American journal of sports medicine. 05/2014;
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    ABSTRACT: Extra-articular hip impingement can be the result of psoas impingement (PI), subspine impingement (SSI), ischiofemoral impingement (IFI), and greater trochanteric/pelvic impingement (GTPI). Symptoms may be due to bony abutment or soft-tissue irritation, and often, it is a challenge to differentiate among symptoms preoperatively. Currently, the clinical picture and diagnostic criteria are still being refined for these conditions. This systematic review was conducted to examine each condition and elucidate the indications for, treatment options for, and clinical outcomes of surgical management. We searched online databases (Medline, Embase, and PubMed) for English-language clinical studies published from database inception through December 31, 2013, addressing the surgical treatment of PI, SSI, IFI, and GTPI. For each condition, 2 independent assessors reviewed eligible studies. Descriptive statistics are presented. Overall, 9,521 studies were initially retrieved; ultimately, 14 studies were included examining 333 hips. For PI, arthroscopic surgery resulted in 88% of patients achieving good to excellent results, as well as significant improvements in the Harris Hip Score (P = .008), Hip Outcome Score-Activities of Daily Living (P = .02), and Hip Outcome Score-Sport (P = .04). For SSI, arthroscopic decompression, with no major complications, resulted in a mean 18.5° improvement in flexion range of motion, as well as improvements in pain (mean visual analog scale score of 5.9 points preoperatively and 1.2 points postoperatively) and the modified Harris Hip Score (mean of 64.97 points preoperatively and 91.3 points postoperatively). For both IFI and GTPI, open procedures anecdotally improved patient symptoms, with no formal objective outcomes data reported. This review suggests that there is some evidence to support that surgical treatment, by arthroscopy for PI and SSI and by open surgery for IFI and GTPI, results in improved patient outcomes. Systematic review of Level IV and V (case report) studies.
    Arthroscopy The Journal of Arthroscopic and Related Surgery 05/2014; · 3.10 Impact Factor
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    ABSTRACT: BACKGROUND:In the diagnosis and surgical treatment of cam-type femoroacetabular impingement (FAI), 3-dimensional (3D) imaging is the gold standard for detecting femoral head-neck junction malformations preoperatively. Intraoperative fluoroscopy is used by many surgeons to evaluate and verify adequate correction of the deformity. PURPOSE:(1) To compare radial reformatted computed tomography (CT) scans with 6 defined intraoperative fluoroscopic views before surgical correction to determine whether fluoroscopy could adequately depict cam deformity, and (2) to define the influence of femoral version on the clock-face location of the maximum cam deformity on these views. STUDY DESIGN:Cohort study (diagnosis); Level of evidence, 2. METHODS:A consecutive series of 50 hips (48 patients) that underwent arthroscopic treatment for symptomatic FAI by a single surgeon were analyzed. Each patient underwent a CT scan and 6 consistent intraoperative fluoroscopy views: 3 views in hip extension and 3 views in hip flexion of 50°. The alpha angles of each of the fluoroscopic images were compared with the radial reformatted CT using a 3D software program. Femoral version was also defined on CT studies. Statistical analysis was performed using the Student t test, with P < .05 defined as significant. RESULTS:Fifty-two percent of patients were male, average age 28 years (range, 15-56 years). The maximum mean alpha angle on fluoroscopy was 65° (range, 37°-93°) and was located on the anteroposterior (AP) 30° external rotation (ER) fluoroscopy view. In comparison, the mean CT-derived maximum alpha angle was 67° and was located at 1:15 (P = .57). The mean clock-face positions of each of the fluoroscopy views (standardized to the right hip) were AP 30° internal rotation, 11:45; AP 0° (neutral) rotation, 12:30; AP 30° ER, 1:00; flexion/0° (neutral) rotation, 1:45; flexion/40° ER, 2:15; and flexion/60° ER, 2:45. Increased femoral anteversion (>20°) was associated with a significant change in the location of the maximum alpha angle (1:45 vs 1:15; P = .002). CONCLUSION:The described 6 fluoroscopic views are very helpful in localization and visualization of the typical cam deformity from 11:45 to 2:45 and can be used to reliably confirm a complete intraoperative resection of cam-type deformity in most patients. These views correlate with preoperative 3D imaging and may be of even greater importance in the absence of preoperative 3D imaging.
    The American journal of sports medicine 04/2014; · 3.61 Impact Factor
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    ABSTRACT: BACKGROUND:There are limited data regarding outcomes and return to sports after surgery for acute versus chronic proximal hamstring ruptures. HYPOTHESIS:Surgery for chronic proximal hamstring ruptures leads to improved outcomes and return to sports but at a lower level than with acute repair. Proximal hamstring reconstruction with an Achilles allograft for chronic ruptures is successful when direct repair is not possible. STUDY DESIGN:Cohort study; Level of evidence, 3. METHODS:Between 2002 and 2012, a total of 72 patients with a traumatic proximal hamstring rupture (51 acute, 21 chronic) underwent either direct tendon repair with suture anchors (n = 58) or Achilles allograft tendon reconstruction (n = 14). Results from the Single Assessment Numeric Evaluation (SANE) for activities of daily living (ADL) and sports-related activities, Short Form-12 (SF-12), visual analog scale (VAS), and a patient satisfaction questionnaire were obtained. RESULTS:The mean time to surgery in the chronic group was 441.4 days versus 17.8 days in the acute group. At a mean follow-up of 45 months, patients with chronic tears had inferior sports activity scores (70.2% vs 80.3%, respectively; P = .026) and a trend for decreased ADL scores (86.5% vs 93.3%, respectively; P = .085) compared with those with acute tears. Patients with chronic tears, however, reported significant improvements postoperatively for both sports activity scores (30.3% to 70.2%; P < .01) and ADL scores (56.1% to 86.5%; P < .01). Greater than 5 to 6 cm of retraction in the chronic group was predictive of the need for allograft reconstruction (P = .015) and resulted in ADL and sports activity scores equal to those of chronic repair (P = .507 and P = .904, respectively). There were no significant differences between groups in SF-12, VAS, or patient satisfaction outcomes (mean, 85.2% satisfaction overall). CONCLUSION:Acute repair was superior to chronic surgery with regard to return to sports. Acute and chronic proximal hamstring repair and allograft reconstruction had favorable results for ADL. For low-demand patients or those with medical comorbidities, delayed repair or reconstruction might be considered with an expected 87% return to normal ADL. For patients who desire to return to sports, acute repair is recommended.
    The American journal of sports medicine 04/2014; · 3.61 Impact Factor
  • Arthroscopy The Journal of Arthroscopic and Related Surgery 02/2014; 30(2):155-6. · 3.10 Impact Factor
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    ABSTRACT: The learning curve for hip arthroscopy is consistently characterized as "steep." The purpose of this systematic review was to (1) identify the various learning curves reported in the literature, (2) examine the evidence supporting these curves, and (3) determine whether this evidence supports an accepted number of cases needed to achieve proficiency. The electronic databases Embase and Medline were screened for any clinical studies reporting learning curves in hip arthroscopy. Two reviewers conducted a full-text review of eligible studies and a hand search of conference proceedings and reference sections of the included articles. Inclusion/exclusion criteria were applied, and a quality assessment was completed for each included article. Descriptive statistics were compiled. We identified 6 studies with a total of 1,063 patients. Studies grouped surgical cases into "early" versus "late" in a surgeon's experience, with 30 cases being the most common cutoff used. Most of these studies used descriptive statistics and operative time and complication rates as measures of competence. Five of 6 studies showed improvement in these measures between early and late experience, but only one study proposed a bona fide curve. This review shows that when 30 cases was used as the cutoff point to differentiate between early and late cases in a surgeon's experience, there were significant reductions in operative time and complication rates. However, there was insufficient evidence to quantify the learning curve and validate 30, or any number of cases, as the point at which the learning curve plateaus. As a result, this number should be interpreted with caution. Level IV, systematic review of Level IV studies.
    Arthroscopy The Journal of Arthroscopic and Related Surgery 01/2014; · 3.10 Impact Factor
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    ABSTRACT: The variety of hip pathology that can be addressed in a minimally invasive fashion in the young, pre-arthritic patient has rapidly grown in parallel with technical advances in hip arthroscopy. However, the indications and limits of arthroscopy must be carefully defined and indications must evolve correspondingly to avoid an increase in failure rates and unsatisfactory clinical outcomes. Some diagnoses may be better and more comprehensively addressed with open procedures or combined surgical approaches. The purpose of this article is to provide an unbiased and evidence-based review of conditions of the pre-arthritic hip to define our current understanding of the advantages, disadvantages, and limitations of an arthroscopic approach.
    Arthroscopy The Journal of Arthroscopic and Related Surgery 01/2014; 30(1):99–110. · 3.10 Impact Factor
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    ABSTRACT: Purpose Extra-articular hip impingement can be the result of psoas impingement (PI), subspine impingement (SSI), ischiofemoral impingement (IFI), and greater trochanteric/pelvic impingement (GTPI). Symptoms may be due to bony abutment or soft-tissue irritation, and often, it is a challenge to differentiate among symptoms preoperatively. Currently, the clinical picture and diagnostic criteria are still being refined for these conditions. This systematic review was conducted to examine each condition and elucidate the indications for, treatment options for, and clinical outcomes of surgical management. Methods We searched online databases (Medline, Embase, and PubMed) for English-language clinical studies published from database inception through December 31, 2013, addressing the surgical treatment of PI, SSI, IFI, and GTPI. For each condition, 2 independent assessors reviewed eligible studies. Descriptive statistics are presented. Results Overall, 9,521 studies were initially retrieved; ultimately, 14 studies were included examining 333 hips. For PI, arthroscopic surgery resulted in 88% of patients achieving good to excellent results, as well as significant improvements in the Harris Hip Score (P = .008), Hip Outcome Score–Activities of Daily Living (P = .02), and Hip Outcome Score–Sport (P = .04). For SSI, arthroscopic decompression, with no major complications, resulted in a mean 18.5° improvement in flexion range of motion, as well as improvements in pain (mean visual analog scale score of 5.9 points preoperatively and 1.2 points postoperatively) and the modified Harris Hip Score (mean of 64.97 points preoperatively and 91.3 points postoperatively). For both IFI and GTPI, open procedures anecdotally improved patient symptoms, with no formal objective outcomes data reported. Conclusions This review suggests that there is some evidence to support that surgical treatment, by arthroscopy for PI and SSI and by open surgery for IFI and GTPI, results in improved patient outcomes. Level of Evidence Systematic review of Level IV and V (case report) studies.
    Arthroscopy The Journal of Arthroscopic and Related Surgery 01/2014; · 3.10 Impact Factor
  • Arthroscopy The Journal of Arthroscopic and Related Surgery 01/2014; 30(2):155–156. · 3.10 Impact Factor
  • Osteoarthritis and Cartilage 01/2014; · 4.26 Impact Factor
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    ABSTRACT: The purposes of this study were to define the anatomy of the anterior inferior iliac spine (AIIS) and its relation to the footprint of the rectus femoris tendon and to evaluate on the clinical outcomes after AIIS/subspine decompression. The rectus origin was dissected and detached in 11 male cadaveric hips with a mean age of 54.3 ± 14.3 years (range, 33 to 74 years). The proximal-distal and medial-lateral extent of the footprint and its relation to the AIIS and acetabular rim were evaluated, with the 12-o'clock position defined as directly lateral at the insertion of the indirect head of the rectus tendon and the 1- to 6-o'clock positions defined as anterior acetabular positions. To assess the safety and efficacy of subspine decompression for AIIS deformity, clinical correlation of a series of 163 AIIS decompressions (mean age, 27.8 years; age range, 14 to 52 years) performed from January 2011 to January 2012 was completed, and outcome scores, strength deficits, and ruptures were assessed by manual muscle testing and postoperative radiographs. All patients presented with symptomatic FAI with proximal femoral and/or acetabular deformity and type 2 (131 hips) or type 3 (32 hips) AIIS morphology as defined by Hetsroni et al. The mean proximal-distal and medial-lateral distances for the rectus origin footprint were 2.2 ± 0.1 cm (range, 2.1 to 2.4 cm) and 1.6 ± 0.3 cm (range, 1.2 to 2.3 cm), respectively. There was a characteristic bare area at the anteromedial AIIS. On the clock face, the lateral margin (1-o'clock to 1:30 position) and medial margin (2-o'clock to 2:30 position) of the AIIS and the indirect head of the rectus (12 o'clock) were consistent for all specimens. In the clinical series, 163 AIIS decompressions were performed for symptomatic subspine impingement. The mean modified Harris Hip Score was 63.1 points (range, 21 to 90 points) preoperatively compared with 85.3 points (range, 37 to 100 points) at a mean follow-up of 11.1 ± 4.1 months (range, 6 to 24 months) (P < .01). Short Form 12 scores improved significantly from a mean of 70.4 (range, 34 to 93) preoperatively to a mean of 81.3 (range, 31 to 99) postoperatively (P < .01). The mean pain score on a visual analog scale also improved significantly from a mean of 4.9 (range, 0.1 to 8.6) preoperatively to a mean of 1.9 (range, 0 to 7.8) postoperatively (P < .01). The mean alpha angle improved from 61.5° (range, 35° to 90°) preoperatively to 49° (range, 35° to 63°) postoperatively on anteroposterior radiographs and from 71° (range, 45° to 90°) preoperatively to 44.3° (range, 37° to 60°) postoperatively on lateral radiographs. No short- or long-term hip flexion deficits or rectus femoris avulsions were noted with up to 2 years' follow-up. The origin of the rectus femoris tendon is broad on the AIIS and protective against direct head detachment with subspine decompression. This broad origin and consistent bare area anteromedially on the AIIS can be readily used by surgeons to perform a safe AIIS resection in cases of symptomatic impingement. Arthroscopic subspine decompression in addition to osteoplasty for symptomatic cam- and/or pincer-type FAI deformities can reliably improve outcome scores without significant hip flexion deficits or AIIS/rectus femoris avulsions. The direct head of the rectus tendon has a broad insertion on the AIIS, and an area devoid of tendon provides a "safe zone" for subspine decompression in cases of symptomatic AIIS impingement.
    Arthroscopy The Journal of Arthroscopic and Related Surgery 10/2013; · 3.10 Impact Factor
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    ABSTRACT: The mechanical causes of hip pain in a young athlete often reflect a complex combination of static and dynamic factors. A comprehensive diagnostic approach is paramount to the development of a rational treatment strategy that will address all underlying pathologic factors. The goals of this paper are to highlight the pertinent biomechanical factors of the hip joint in femoroacetabular impingement and to discuss the clinical history, physical examination, and radiographic findings that are essential to formulating a proper diagnosis and an effective treatment plan. In addition, the current literature and reported outcomes of femoroacetabular impingement surgery in athletic patients are reviewed.
    The Journal of Bone and Joint Surgery 09/2013; 95(18):e1331-16. · 3.23 Impact Factor
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    ABSTRACT: BACKGROUND:Femoroacetabular impingement (FAI) is one of the most common causes of early cartilage and labral damage in the nondysplastic hip. Biomarkers of cartilage degradation and inflammation are associated with osteoarthritis. It was not known whether patients with FAI have elevated levels of biomarkers of cartilage degradation and inflammation. HYPOTHESIS:Compared with athletes without FAI, athletes with FAI would have elevated levels of the inflammatory C-reactive protein (CRP) and cartilage oligomeric matrix protein (COMP), a cartilage degradation marker. STUDY DESIGN:Controlled laboratory study. METHODS:Male athletes with radiographically confirmed FAI (n = 10) were compared with male athletes with radiographically normal hips with no evidence of FAI or hip dysplasia (n = 19). Plasma levels of COMP and CRP were measured, and subjects also completed the Short Form-12 (SF-12) and Hip Disability and Osteoarthritis Outcome Score (HOOS) surveys. RESULTS:Compared with controls, athletes with FAI had a 24% increase in COMP levels and a 276% increase in CRP levels as well as a 22% decrease in SF-12 physical component scores and decreases in all of the HOOS subscale scores. CONCLUSION:Athletes with FAI demonstrate early biochemical signs of increased cartilage turnover and systemic inflammation. CLINICAL RELEVANCE:Chondral injury secondary to the repetitive microtrauma of FAI might be reliably detected with biomarkers. In the future, these biomarkers might be used as screening tools to identify at-risk patients and assess the efficacy of therapeutic interventions such as hip preservation surgery in altering the natural history and progression to osteoarthritis.
    The American journal of sports medicine 08/2013; · 3.61 Impact Factor
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    ABSTRACT: Hip preservation surgery has become more commonplace, yet when it fails, it is unclear why it does so. Understanding failed procedures should lead to improved surgical results. The purposes of this study were to (1) characterize patients undergoing hip preservation surgery after prior procedures; (2) compare demographics, hip pain, and function in patients with prior procedures with those undergoing primary surgery; (3) determine the types of previous procedures and the reasons for secondary surgery; and (4) report the procedure profile of the secondary surgeries. A prospective, multicenter hip preservation database of 2263 patients (2386 surgery cases) was reviewed to identify 352 patients (359 hips, 15% of the total) who had prior surgery. Patient demographics, type of previous surgery, diagnostic categories, clinical scores, and type of secondary procedure were recorded. For patients undergoing secondary surgery, the average age was 23 years and 70% were female. Hip pain and function were similar between patients undergoing primary and secondary surgery. The previous surgical approaches were open in 52% and hip arthroscopy in 48%. In the femoroacetabular impingement and adult acetabular dysplasia subgroups, hip arthroscopy was the most common previous surgical approach (86% and 64%, respectively). Inadequately corrected structural disease was the most common reason for secondary surgery. Femoral osteochondroplasty and acetabular reorientation were the most common secondary procedures. Inadequately corrected structural disease (femoroacetabular impingement or acetabular dysplasia) was commonly associated with the need for secondary hip preservation surgery. Although we do not have data to identify other technical failures, the available data suggest primary treatments should encompass comprehensive deformity correction when indicated. Level III, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.
    Clinical Orthopaedics and Related Research 08/2013; · 2.79 Impact Factor
  • Christopher M Larson, Rebecca M Stone
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    ABSTRACT: There has been an increasing body of literature regarding arthroscopic management of femoroacetabular impingement (FAI). Refinement of arthroscopic techniques has allowed for more complete management of FAI, and meta-analysis and systematic reviews have shown comparable outcomes to surgical hip dislocation with appropriate indications. There are still, however, pathomorphologies that are not accessible or much more challenging to address arthroscopically, and open corrective procedures should be considered in these situations. Extra-articular FAI is receiving increased attention and can be secondary to anterior inferior iliac spine/subspine impingement, trochanteric-pelvic impingement, and ischio-femoral impingement. Femoral and acetabular version and their impact on hip stability as well as the concept of impingement induced instability are being increasingly recognized. Acetabular labral and capsular management and repair techniques have also received increased attention. Finally, 3-dimensional imaging and dynamic software analysis are beginning to emerge as potential tools to better evaluate hip pathomorphology.
    Current Reviews in Musculoskeletal Medicine 06/2013;

Publication Stats

476 Citations
127.62 Total Impact Points

Institutions

  • 2009–2014
    • Minnesota Orthopedic Sports Medicine Institute at Twin Cities Orthopedics
      Edina, Minnesota, United States
    • University of Minnesota Twin Cities
      Minneapolis, Minnesota, United States
  • 2013
    • University of Pennsylvania
      Philadelphia, Pennsylvania, United States
    • Meir Medical Center
      Kafr Saba, Central District, Israel
    • University of Michigan
      • Department of Orthopaedic Surgery
      Ann Arbor, Michigan, United States
    • Dokuz Eylul University
      Ismir, İzmir, Turkey
  • 2012
    • Washington University in St. Louis
      • Department of Orthopaedic Surgery
      Saint Louis, MO, United States
    • The University of Calgary
      Calgary, Alberta, Canada
    • Mayo Foundation for Medical Education and Research
      • Department of Orthopaedic Surgery
      Scottsdale, AZ, United States
    • Hospital for Special Surgery
      • Department of Orthopaedic Surgery
      New York City, New York, United States
    • Tel Aviv University
      Tell Afif, Tel Aviv, Israel
  • 2008–2010
    • University of North Carolina at Chapel Hill
      • Department of Orthopaedics
      Chapel Hill, NC, United States
    • Instituto Nacional de Rehabilitación
      Ciudad de México, The Federal District, Mexico