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Dive into the research topics where Christopher M. Larson is active.

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Featured researches published by Christopher M. Larson.


Arthroscopy | 2009

Arthroscopic Debridement Versus Refixation of the Acetabular Labrum Associated With Femoroacetabular Impingement

Christopher M. Larson; M. Russell Giveans

PURPOSE The purpose of this study was to compare the outcomes of arthroscopic labral debridement with those of labral refixation. METHODS We reviewed patients who underwent labral debridement during a period before the development of labral repair techniques. Patients with labral tears deemed repairable with our current arthroscopic technique were compared with patients who underwent labral refixation with a minimum 1 of year of follow-up. To better match the 2 groups, only patients with labral pathology caused by pincer-type or combined pincer- and cam-type femoroacetabular impingement were included. In the first 36 hips the labrum was debrided (group 1); in the next 39 hips the labrum underwent refixation (group 2). Outcomes were measured preoperatively and postoperatively with the modified Harris Hip Score (HHS), Short Form 12, and visual analog scale for pain. Preoperative and postoperative radiographs were obtained to evaluate bony resection (alpha angle) and osteoarthritis (Tönnis grade). RESULTS The mean age was 31 years in group 1, with a mean follow-up of 21.4 months, and 27 years in group 2, with a mean follow-up of 16.5 months. Preoperative subjective outcomes scores were not significantly different between groups. At the 1-year follow-up visit, subjective outcomes were significantly improved (P < .01) in both groups. HHSs were significantly better for the refixation group (94.3) compared with the debridement group (88.9) at 1 year (P = .029). At most recent follow-up, good to excellent results were noted in 66.7% of hips in the debridement group compared with 89.7% of hips in the refixation group (P < .01). CONCLUSIONS Although other variables could have influenced these outcomes, these preliminary results indicate that labral refixation resulted in better HHS outcomes and a greater percentage of good to excellent results compared with the results of labral debridement in an earlier cohort. LEVEL OF EVIDENCE Level III, retrospective comparative study.


American Journal of Sports Medicine | 2012

Arthroscopic Debridement Versus Refixation of the Acetabular Labrum Associated With Femoroacetabular Impingement Mean 3.5-Year Follow-up

Christopher M. Larson; M. Russell Giveans; Rebecca M. Stone

Background: The acetabular labrum provides a sealing function and a degree of hip joint stability. Limited, short-term follow-up studies suggest that labral refixation/preservation leads to superior outcomes compared with labral debridement/excision. Purpose: To compare the results of labral refixation versus focal labral excision/debridement in a cohort of patients who underwent arthroscopic correction of femoroacetabular impingement (FAI). Study Design: Cohort study; Level of evidence, 3. Methods: We reported on patients who underwent labral debridement/focal labral excision during a period before the development of labral repair techniques. Patients with labral tears thought to be repairable with our current arthroscopic technique were compared with a cohort of patients who underwent labral refixation. To better match the 2 groups, only patients with labral pincer- or combined-type FAI were included. In the first 44 hips, the labrum was focally excised/debrided (group 1); in the next 50 hips, the labrum was refixed (group 2). Outcomes were measured with the modified Harris Hip Score (HHS), Short Form 12 (SF-12), and a visual analog scale (VAS) for pain preoperatively and postoperatively. Preoperative and postoperative radiographs were obtained to evaluate bony resection. Results: The mean age was 32 years in group 1 and 28 years in group 2 with a mean follow-up of 42 months (range, 24-72 months). Preoperative mean subjective outcome scores were not significantly different between groups. At a mean 3.5 years’ follow-up, subjective outcomes were significantly improved (P < .01) for both groups compared with preoperative scores. The HHS (P = .001), SF-12 (P = .041), and VAS pain scores (P = .004) were all significantly better for the refixation group compared with the debridement group at the most recent follow-up. At a mean 3.5 years’ follow-up, good to excellent results were noted in 68% of the focal excision/debridement group and 92% of the refixation group (P = .004). Conclusion: Although other factors may have influenced these results, labral refixation compared with an earlier cohort of focal labral excision/debridement resulted in better HHS, SF-12, and VAS pain outcomes and a greater percentage of good to excellent results at a mean 3.5-year follow-up.


Journal of Pediatric Orthopaedics | 2000

Bone mineral density and fractures in boys with Duchenne muscular dystrophy

Christopher M. Larson; Richard C. Henderson

The relationships between bone density, mobility, and fractures were assessed in 41 boys with Duchenne muscular dystrophy. Bone density in the lumbar spine was only slightly decreased while the boys were ambulatory (mean z-score, -0.8), but significantly decreased with loss of ambulation (mean z-score, -1.7). In contrast, bone density in the proximal femur was profoundly diminished even when gait was minimally affected (mean z-score, -1.6), and then progressively decreased to nearly 4 standard deviations below age-matched normals (mean z-score, -3.9). These are consistent with the findings that 18 (44%) of the boys sustained a fracture, 66% of these fractures involved the lower extremities, and there were no spinal compression fractures. Furthermore, four (44%) of nine boys who were walking with aids or support at the time of fracture never resumed walking after the fracture. Osteoporosis is most profound in the lower extremities of boys with Duchenne muscular dystrophy, and begins to develop early while still ambulating. Frequent fractures that may result in loss of ambulation are the clinical consequences.


Arthroscopy | 2012

The Development and Validation of a Self-Administered Quality-of-Life Outcome Measure for Young, Active Patients With Symptomatic Hip Disease: The International Hip Outcome Tool (iHOT-33)

Nicholas Mohtadi; Damian R. Griffin; M. Elizabeth Pedersen; Denise Chan; Marc R. Safran; Nicholas R. Parsons; Jon K. Sekiya; Bryan T. Kelly; Jason Werle; Michael Leunig; Joseph C. McCarthy; Hal D. Martin; J. W. Thomas Byrd; Marc J. Philippon; RobRoy L. Martin; Carlos A. Guanche; John C. Clohisy; Thomas G. Sampson; Mininder S. Kocher; Christopher M. Larson

PURPOSE The purpose of this study was to develop a self-administered evaluative tool to measure health-related quality of life in young, active patients with hip disorders. METHODS This outcome measure was developed for active patients (aged 18 to 60 years, Tegner activity level ≥ 4) presenting with a variety of symptomatic hip conditions. This multicenter study recruited patients from international hip arthroscopy and arthroplasty surgeon practices. The outcome was created using a process of item generation (51 patients), item reduction (150 patients), and pretesting (31 patients). The questionnaire was tested for test-retest reliability (123 patients); face, content, and construct validity (51 patients); and responsiveness over a 6-month period in post-arthroscopy patients (27 patients). RESULTS Initially, 146 items were identified. This number was reduced to 60 through item reduction, and the items were categorized into 4 domains: (1) symptoms and functional limitations; (2) sports and recreational physical activities; (3) job-related concerns; and (4) social, emotional, and lifestyle concerns. The items were then formatted using a visual analog scale. Test-retest reliability showed Pearson correlations greater than 0.80 for 33 of the 60 questions. The intraclass correlation statistic was 0.78, and the Cronbach α was .99. Face validity and content validity were ensured during development, and construct validity was shown with a correlation of 0.81 to the Non-Arthritic Hip Score. Responsiveness was shown with a paired t test (P ≤ .01), effect size of 2.0, standardized response mean of 1.7, responsiveness ratio of 6.7, and minimal clinically important difference of 6 points. CONCLUSIONS We have developed a new quality-of-life patient-reported outcome measure, the 33-item International Hip Outcome Tool (iHOT-33). This questionnaire uses a visual analog scale response format designed for computer self-administration by young, active patients with hip pathology. Its development has followed the most rigorous methodology involving a very large number of patients. The iHOT-33 has been shown to be reliable; shows face, content, and construct validity; and is highly responsive to clinical change. In our opinion the iHOT-33 can be used as a primary outcome measure for prospective patient evaluation and randomized clinical trials.


Arthroscopy | 2011

Making a Case for Anterior Inferior Iliac Spine/Subspine Hip Impingement: Three Representative Case Reports and Proposed Concept

Christopher M. Larson; Bryan T. Kelly; Rebecca M. Stone

Femoroacetabular impingement is typically described as occurring due to a conflict between the femoral head-neck junction and acetabular rim. A prior case report described an open decompression of the anterior inferior iliac spine (AIIS) due to impingement against the proximal femur. AIIS impingement may be developmental or the result of a prior AIIS avulsion or pelvic osteotomy. We describe 3 representative cases with minimum 1-year follow-up treated with an arthroscopic AIIS decompression.


Arthroscopy | 2008

A geographic zone method to describe intra-articular pathology in hip arthroscopy: cadaveric study and preliminary report.

Victor M. Ilizaliturri; J. W. Thomas Byrd; Thomas G. Sampson; Carlos A. Guanche; Marc J. Philippon; Bryan T. Kelly; Michael Dienst; Rodrigo Mardones; Paul Shonnard; Christopher M. Larson

PURPOSE Our purpose was to develop an alternative method to divide the acetabulum and femoral head into different zones based on anatomic landmarks clearly visible during arthroscopy to facilitate reporting the geographic location of intra-articular injuries. METHODS Two vertical lines are positioned across the acetabulum aligned with the anterior and posterior limits of the acetabular notch. A horizontal line is positioned aligned with the superior limit of the notch perpendicular to the previous lines. The lines divide the acetabulum into 6 zones. Numbers are assigned to each zone in consecutive order. Zone 1 is the anterior-inferior acetabulum. The numbers progress around the notch until zone 5 is assigned to the posterior-inferior acetabulum. Zone 6 is the acetabular notch. The same method is applied to the femoral head. Six experienced hip arthroscopists were instructed in the zone and clock-face methods and were asked to identify and describe the geographic locations of lesions at the acetabular rim, acetabular cartilage, and femoral head in the same cadaveric specimen. RESULTS The zone method was more reproducible than the clock-face method in the geographic description of intra-articular injuries on the acetabulum and the femoral head. CONCLUSIONS Among a group of expert hip arthroscopists, the zone method was more reproducible than the clock-face method. CLINICAL RELEVANCE The presented method divides the acetabulum into 6 different zones based on the acetabular notch. The zones are the same for right- and left-side hips. The same method is applied for the femoral head allowing, for the first time, a geographic description of pathology.


American Journal of Sports Medicine | 2002

Intramedullary Screw Fixation of Jones Fractures Analysis of Failure

Christopher M. Larson; Louis C. Almekinders; Timothy N. Taft; William E. Garrett

Treatment failures after screw fixation of Jones fractures are reported to be infrequent. Between 1993 and 1999, 15 patients (mean age, 21.7 years) underwent cannulated screw fixation of a Jones fracture at our institution. There were six treatment failures: four re-fractures and two symptomatic nonunions. The mean time to full activity was 6.8 weeks for the patients with failure compared with 9 weeks for patients who did not have complications. Although all patients were asymptomatic and radiographically progressing to union before return to full activity, only one of six patients with failures had complete radiographic union, compared with six of seven patients with no complications. There was a higher proportion of elite athletes (division I or professional level) among the failure group (83%) compared with those without complications (11%). There were no significant differences in age, sex, screw diameter, use of bone graft, or age of fracture between patients with failures and those without complications. Return to full activity, especially among elite athletes, before complete radiographic union was predictive of failure. Even though intramedullary screw fixation offers advantages over nonoperative treatment, a significant risk of postoperative complications exists.


Arthroscopy | 2012

Anterior Inferior Iliac Spine Deformity as an Extra-Articular Source for Hip Impingement: A Series of 10 Patients Treated With Arthroscopic Decompression

Iftach Hetsroni; Christopher M. Larson; Katrina Dela Torre; Robert M. Zbeda; Erin Magennis; Bryan T. Kelly

PURPOSE To describe an arthroscopic technique for decompression of a prominent anterior inferior iliac spine (AIIS) leading to extra-articular hip impingement and to provide short-term outcome after this procedure. METHODS We retrospectively reviewed office charts, imaging studies, operative reports, arthroscopic images, preoperative and postoperative hip flexion range of motion, and preoperative and postoperative modified Harris Hip Scores in a consecutive series of 10 male patients who had arthroscopic decompression of symptomatic AIIS deformities leading to extra-articular hip impingement. The procedure was performed through standard anterolateral and mid-anterior hip arthroscopy portals that were also used to explore the joint and address concomitant intra-articular pathologies. RESULTS The mean age was 24.9 years, with 8 of 10 patients aged younger than 30 years. In 9 patients, an anterior cam lesion was identified and decompressed before the AIIS decompression. The mean follow-up time was 14.7 months (range, 6 to 26 months). Hip flexion range of motion improved from 99° ± 7° before surgery to 117° ± 8° after surgery (P < .001). The modified Harris Hip Score improved from 64 ± 18 before surgery to 98 ± 2 at latest follow-up after surgery (P < .001). CONCLUSIONS Arthroscopic decompression of a symptomatic AIIS deformity is a reproducible procedure that can provide excellent outcomes at short-term follow-up. As opposed to using an open approach for decompressing a prominent AIIS, an arthroscopic approach may be of particular value in patients with mixed intra- and extra-articular sources of hip dysfunction, because it enables the surgeon to address all pathologies with a single arthroscopic procedure. LEVEL OF EVIDENCE Level IV, therapeutic case series.


Arthroscopy | 2011

Treatment of Athletes With Symptomatic Intra-Articular Hip Pathology and Athletic Pubalgia/Sports Hernia: A Case Series

Christopher M. Larson; Bradley R. Pierce; M. Russell Giveans

PURPOSE The purpose of the study was to evaluate the results of surgical treatment in athletes with associated intra-articular hip pathology and extra-articular sports pubalgia. METHODS Between December 2003 and September 2009, 37 hips (mean patient age, 25 years) were diagnosed with both symptomatic athletic pubalgia and symptomatic intra-articular hip joint pathology. There were 8 professional athletes, 15 collegiate athletes, 5 elite high school athletes, and 9 competitive club athletes. Outcomes included an evaluation regarding return to sports and modified Harris Hip Score, Short Form 12 score, and visual analog scale score. RESULTS We evaluated 37 hips at a mean of 29 months (range, 12 to 78 months) after the index surgery. Thirty-one hips underwent thirty-five athletic pubalgia surgeries. Hip arthroscopy was performed in 32 hips (30 cases of femoroacetabular impingement treatment, 1 traumatic labral tear, and 1 borderline dysplasia). Of 16 hips that had athletic pubalgia surgery as the index procedure, 4 (25%) returned to sports without limitations, and 11 (69%) subsequently had hip arthroscopy at a mean of 20 months after pubalgia surgery. Of 8 hips managed initially with hip arthroscopy alone, 4 (50%) returned to sports without limitations, and 3 (43%) had subsequent pubalgia surgery at a mean of 6 months after hip arthroscopy. Thirteen hips had athletic pubalgia surgery and hip arthroscopy at one setting. Concurrent or eventual surgical treatment of both disorders led to improved postoperative outcomes scores (P < .05) and an unrestricted return to sporting activity in 89% of hips (24 of 27). CONCLUSIONS When surgery only addressed either the athletic pubalgia or intra-articular hip pathology in this patient population, outcomes were suboptimal. Surgical management of both disorders concurrently or in a staged manner led to improved postoperative outcomes scoring and an unrestricted return to sporting activity in 89% of hips. LEVEL OF EVIDENCE Level IV, therapeutic case series.


Clinical Orthopaedics and Related Research | 2013

Anterior Inferior Iliac Spine Morphology Correlates With Hip Range of Motion: A Classification System and Dynamic Model

Iftach Hetsroni; Lazaros A. Poultsides; Asheesh Bedi; Christopher M. Larson; Bryan T. Kelly

BackgroundThe anterior inferior iliac spine (AIIS) contributes to hip dysfunction in patients with symptomatic impingement and resection of a prominent AIIS can reportedly improve function. However, the variability of the AIIS morphology and whether that variability correlates with risk of associated symptomatic impingement are unclear.Questions/purposesWe characterized AIIS morphology in patients with hip impingement and tested the association between specific AIIS variants and hip range of motion.MethodsWe evaluated three-dimensional CT reconstructions of 53 hips (53 patients) with impingement and defined three morphological AIIS variants: Type I when there was a smooth ilium wall between the AIIS and the acetabular rim, Type II when the AIIS extended to the level of the rim, and Type III when the AIIS extended distally to the acetabular rim. A separate cohort of 78 hips (78 patients) with impingement was used to compare hip range of motion among the three AIIS types.ResultsMean hip flexion was limited to 120°, 107°, and 93° in hips with Type I, Type II, and Type III AIIS, respectively. Mean internal rotation was limited to 21°, 11°, and 8° in hips with Type I, Type II, and Type III AIIS, respectively.ConclusionsWhen the AIIS is classified into three variants based on the relationship between the AIIS and the acetabular rim in patients with impingement, Type II and III variants are associated with a decrease in hip flexion and internal rotation, supporting the rationale for considering AIIS decompression for variants that extend to and below the rim.Level of EvidenceLevel III, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

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Bryan T. Kelly

Hospital for Special Surgery

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Jeffrey J. Nepple

Washington University in St. Louis

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