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Dive into the research topics where Ryan M. Nunley is active.

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Featured researches published by Ryan M. Nunley.


Journal of Bone and Joint Surgery, American Volume | 2006

Long-term follow-up of patients with clubfeet treated with extensive soft-tissue release.

Matthew B. Dobbs; Ryan M. Nunley; Perry L. Schoenecker

BACKGROUND Although long-term follow-up studies have shown favorable results, in terms of foot function, after treatment of idiopathic clubfoot with serial manipulations and casts, we know of no long-term follow-up studies of patients in whom clubfoot was treated with an extensive surgical soft-tissue release. METHODS Forty-five patients (seventy-three feet) in whom idiopathic clubfoot was treated with either a posterior release and plantar fasciotomy (eight patients) or an extensive combined posterior, medial, and lateral release (thirty-seven patients) were followed for a mean of thirty years. Patients were evaluated with detailed examination of the lower extremities, a radiographic evaluation that included grading of osteoarthritis, and three independent quality-of-life questionnaires, including the Short Form-36 Medical Outcomes Study. RESULTS At the time of follow-up, the majority of patients in both treatment groups had significant limitation of foot function, which was consistent across the three independent quality-of-life questionnaires. No significant difference between groups was noted with regard to the results of the quality-of-life measures, the range of motion of the ankle or the position of the heel, or the radiographic findings. Six patients who had been treated with only one surgical procedure had better ranges of motion of the ankle and subtalar joints (p < 0.004) than those who had had multiple surgical procedures. CONCLUSIONS Many patients with clubfoot treated with an extensive soft-tissue release have poor long-term foot function. We found a correlation between the extent of the soft-tissue release and the degree of functional impairment. Repeated soft-tissue releases can result in a stiff, painful, and arthritic foot and significantly impaired quality of life.


Clinical Orthopaedics and Related Research | 2007

The frog-leg lateral radiograph accurately visualized hip cam impingement abnormalities.

John C. Clohisy; Ryan M. Nunley; Robert J Otto; Perry L. Schoenecker

Radiographic evaluation of the anterolateral femoral head-neck junction is essential in diagnosing cam femoroacetabular impingement. We hypothesized the frog-leg lateral radiograph can accurately assess femoral head-neck offset abnormalities associated with cam femoroacetabular impingement. We reviewed the radiographs of 61 hips treated for cam impingement and 24 asymptomatic control hips. To characterize the anatomy of the femoral head-neck junction, the femoral head sphericity, the α-angle of Nötzli et al, and head-neck offset were measured on all radiographs. Asphericity of the femoral head was detected more frequently in hips with impingement on all radiographic views when compared with control hips. The average α-angle was greater in hips with impingement on all views, with the greatest difference between hips with impingement and control hips seen on the frog-leg lateral view (65° for hips with impingement versus 47° for control hips). The average head-neck offset was decreased in hips with impingement on all views. The greatest difference between groups was seen on the frog-leg lateral view (6.6 mm for hips with impingement versus 9.3 mm for control hips). The frog-leg lateral radiograph provides accurate visualization of the femoral head-neck offset in patients being evaluated for femoroacetabular impingement. Level of Evidence: Level II, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.


Clinical Orthopaedics and Related Research | 2012

Are Patient-specific Cutting Blocks Cost-effective for Total Knee Arthroplasty?

Ryan M. Nunley; Bradley S. Ellison; Erin L. Ruh; Brandon M. Williams; Keith Foreman; Adrienne D. Ford; Robert L. Barrack

BackgroundUsing patient-specific cutting blocks for TKA increases the cost to the hospital for these procedures, but it has been proposed they may reduce operative times and improve implant alignment, which could reduce the need for revision surgery.Questions/purposesWe compared TKAs performed with patient-specific cutting blocks with those performed with traditional instrumentation to determine whether there was improved operating room time management and component coronal alignment to support use of this technology.MethodsWe retrospectively reviewed 57 patients undergoing primary TKAs using patient-specific custom cutting blocks for osteoarthritis and compared them with 57 matched patients undergoing TKAs with traditional instrumentation during the same period (January 2009 to September 2010). At baseline, the groups were comparable with respect to age, sex, and BMI. We collected data on operative time (total in-room time and tourniquet time) and measured component alignment on plain radiographs.ResultsOn average, TKAs performed with patient-specific instrumentation had similar tourniquet times (61.0 versus 56.2 minutes) but patients were in the operating room 12.1 minutes less (137.2 versus 125.1 minutes) than those in the standard instrumentation group. We observed no difference in the femorotibial angle in the coronal plane between the two groups.ConclusionsPatient-specific instrumentation for TKA shows slight improvement in operating room time management but none in component alignment postoperatively. Therefore, routine use of this new technology may not be cost-effective in its current form.Level of EvidenceLevel III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.


Journal of Arthroplasty | 2013

Why Are Total Knees Failing Today? Etiology of Total Knee Revision in 2010 and 2011

William C. Schroer; Keith R. Berend; Adolph V. Lombardi; C. Lowry Barnes; Michael P. Bolognesi; Michael E. Berend; Merrill A. Ritter; Ryan M. Nunley

Revision knee data from six joint arthroplasty centers were compiled for 2010 and 2011 to determine mechanism of failure and time to failure. Aseptic loosening was the predominant mechanism of failure (31.2%), followed by instability (18.7%), infection (16.2%), polyethylene wear (10.0%), arthrofibrosis (6.9%), and malalignment (6.6%). Mean time to failure was 5.9 years (range 10 days to 31 years). 35.3% of all revisions occurred less than 2 years after the index arthroplasty, 60.2% in the first 5 years. In contrast to previous reports, polyethylene wear is not a leading failure mechanism and rarely presents before 15 years. Implant performance is not a predominant factor of knee failure. Early failure mechanisms are primarily surgeon-dependent.


Journal of Bone and Joint Surgery-british Volume | 2012

Patient specific cutting blocks are currently of no proven value

Robert L. Barrack; Erin L. Ruh; Brandon M. Williams; A. D. Ford; K. Foreman; Ryan M. Nunley

Patient specific cutting guides generated by preoperative Magnetic Resonance Imaging (MRI) of the patients extremity have been proposed as a method of improving the consistency of Total Knee Arthroplasty (TKA) alignment and adding efficiency to the operative procedure. The cost of this option was evaluated by quantifying the savings from decreased operative time and instrument processing costs compared to the additional cost of the MRI and the guide. Coronal plane alignment was measured in an unselected consecutive series of 200 TKAs, 100 with standard instrumentation and 100 with custom cutting guides. While the cutting guides had significantly lower total operative time and instrument processing time, the estimated


Journal of Bone and Joint Surgery, American Volume | 2007

Periacetabular osteotomy for the treatment of acetabular dysplasia associated with major aspherical femoral head deformities

John C. Clohisy; Ryan M. Nunley; Madelyn C. Curry; Perry L. Schoenecker

322 savings was overwhelmed by the


Clinical Orthopaedics and Related Research | 2015

Systematic Review of Patient-specific Instrumentation in Total Knee Arthroplasty: New but Not Improved

Adam Sassoon; Denis Nam; Ryan M. Nunley; Robert L. Barrack

1,500 additional cost of the MRI and the cutting guide. All measures of coronal plane alignment were equivalent between the two groups. The data does not currently support the proposition that patient specific guides add value to TKA.


American Journal of Sports Medicine | 2011

Clinical and Radiographic Predictors of Intra-articular Hip Disease in Arthroscopy

Jeffrey J. Nepple; John C. Carlisle; Ryan M. Nunley; John C. Clohisy

BACKGROUND Acetabular dysplasia associated with deformity of the proximal part of the femur can result in hip dysfunction and degenerative arthritis in young adults. The optimal method of surgical correction for these challenging combined deformities remains controversial. METHODS We retrospectively analyzed twenty-four hips in twenty patients who underwent a Bernese periacetabular osteotomy, which was done with a proximal femoral valgus-producing osteotomy in thirteen hips, for the treatment of acetabular dysplasia associated with proximal femoral structural abnormalities. The average age of the patients at the time of surgery was 22.7 years, and the average duration of clinical follow-up was 4.5 years. The Harris hip score and overall patient satisfaction with surgery were used to assess hip function and clinical results. Plain radiographs were used to assess the correction of the deformity, healing of the osteotomy, and progression of degenerative arthritis. RESULTS The mean Harris hip score increased from 68.8 points preoperatively to 91.3 points at the time of the most recent follow-up (p<0.0001). Sixteen patients (nineteen hips) had an excellent clinical result, and one patient (one hip) had a good result. Two patients (two hips) had a fair result, and one patient (two hips) had a poor result. Twenty-two of the twenty-four hips improved clinically. There was an average improvement of 27.6 degrees in the lateral center-edge angle of Wiberg (p<0.0001), an average improvement of 33.1 degrees in the anterior center-edge angle of Lequesne and de Seze (p<0.0001), and an average improvement of 16.5 degrees in the acetabular roof obliquity (p<0.0001). The hip center was translated medially an average of 6.3 mm (p=0.0003). The Tönnis osteoarthritis grade was unchanged in twenty hips, progressed one grade in three hips, and progressed two grades in one hip. There were three major technical complications. At the time of the most recent follow-up, none of the hips had required total hip arthroplasty. CONCLUSIONS The combination of acetabular dysplasia and proximal femoral deformities presents a complex reconstructive problem. The range of motion and radiographic assessment of the hip are major factors in the selection of patients for surgery. In selected patients, the periacetabular osteotomy combined with concurrent femoral procedures, when indicated, can provide comprehensive deformity correction and improved hip function.


Journal of Bone and Joint Surgery, American Volume | 2011

Clinical presentation of symptomatic acetabular dysplasia in skeletally mature patients.

Ryan M. Nunley; Heidi Prather; Devyani Hunt; Perry L. Schoenecker; John C. Clohisy

BackgroundPatient-specific cutting blocks have been touted as a more efficient and reliable means of achieving neutral mechanical alignment during TKA with the proposed downstream effect of improved clinical outcomes. However, it is not clear to what degree published studies support these assumptions.Questions/purposesWe asked: (1) Do patient-specific cutting blocks achieve neutral mechanical alignment more reliably during TKA when compared with conventional methods? (2) Does patient-specific instrumentation (PSI) provide financial benefit through improved surgical efficiency? (3) Does the use of patient-specific cutting blocks translate to improved clinical results after TKA when compared with conventional instrumentation?MethodsWe performed a systematic review in accordance with Cochrane guidelines of controlled studies (prospective and retrospective) in MEDLINE® and EMBASE® with respect to patient-specific cutting blocks and their effect on alignment, cost, operative time, clinical outcome scores, complications, and survivorship. Sixteen studies (Level I–III on the levels of evidence rubric) were identified and used in addressing the first question, 13 (Level I–III) for the second question, and two (Level III) for the third question. Qualitative assessment of the selected Level I studies was performed using the modified Jadad score; Level II and III studies were rated based on the Newcastle-Ottawa scoring system.ResultsThe majority of studies did not show an improvement in overall limb alignment when PSI was compared with standard instrumentation. Mixed results were seen across studies with regard to the prevalence of alignment outliers when PSI was compared with conventional cutting blocks with some studies demonstrating no difference, some showing an improvement with PSI, and a single study showing worse results with PSI. The studies demonstrated mixed results regarding the influence of PSI on operative times. Decreased operative times were not uniformly observed, and when noted, they were found to be of minimal clinical or financial significance. PSI did reliably reduce the number of instrument trays required for processing perioperatively. The accuracy of the preoperative plan, generated by the PSI manufacturers, was found lacking, often leading to multiple intraoperative changes, thereby disrupting the flow of the operation and negatively impacting efficiency. Limited data exist with regard to the effect of PSI on postoperative function, improvement in pain, and patient satisfaction. Neither of the two studies we identified provided strong evidence to support an advantage favoring the use of PSI. No identified studies addressed survivorship of components placed with PSI compared with those placed with standard instrumentation.ConclusionsPSI for TKA has not reliably demonstrated improvement of postoperative limb or component alignment when compared with standard instrumentation. Although decisive evidence exists to support that PSI requires fewer surgical trays, PSI has not clearly been shown to improve overall surgical efficiency or the cost-effectiveness of TKA. Mid- and long-term data regarding PSI’s effect on functional outcomes and component survivorship do not exist and short-term data are scarce. Limited available literature does not clearly support any improvement of postoperative pain, activity, function, or ROM when PSI is compared with traditional instrumentation.


Journal of Bone and Joint Surgery, American Volume | 2006

Early Results of a New Method of Treatment for Idiopathic Congenital Vertical Talus

Matthew B. Dobbs; Derek B. Purcell; Ryan M. Nunley; Jose A. Morcuende

Background: The arthroscopic treatment of intra-articular hip disease and associated structural abnormalities continues to evolve. Nevertheless, contemporary diagnostic tools have significant limitations in predicting severity of disease preoperatively. Hypothesis: Clinical characteristics and radiographic parameters correlate with and predict intra-articular disease patterns in patients undergoing hip arthroscopy. Study Design: Cohort study; Level of evidence, 3. Methods: In sum, 355 hips in 338 patients undergoing hip arthroscopy by a single surgeon were retrospectively reviewed. Clinical characteristics and radiographic findings (on anteroposterior pelvis and frog lateral radiographs) of mild dysplasia, cam, and pincer-type femoroacetabular impingement were compared with intraoperative labral and chondral disease patterns. Results: Labral tears were present in 90.1% of hips, and acetabular cartilage lesions were present in 67.3%, including 41.7% with grade 3 or 4 chondromalacia. Multivariate logistic regression analysis found male sex, older age (<30, 30-50, >50 years old), Tönnis osteoarthritis grade, and alpha angle >50° on frog lateral radiograph to be independently associated with increased risk of grade 3 or 4 acetabular chondromalacia (all P < .001). Insidious onset of pain (in contrast to acute onset) was independently associated with the presence of acetabular chondromalacia (P = .002). Cam-type femoroacetabular impingement (alpha angle >50°) was strongly associated with more severe labral disease (P < .001). Findings of acetabular dysplasia and pincer femoroacetabular impingement did not remain significantly associated with acetabular chondral disease in the multivariate analysis. Conclusion: Several clinical and radiographic characteristics—most notably, male sex, older age, Tönnis grade, and elevated alpha angle—are associated with more severe intra-articular hip disease. The recognition of these associations between clinical and radiographic characteristics and hip disease patterns is important for patient selection, surgical planning, and patient counseling.

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Robert L. Barrack

Washington University in St. Louis

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Denis Nam

Rush University Medical Center

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John C. Clohisy

Washington University in St. Louis

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Staci R. Johnson

Washington University in St. Louis

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Erin L. Ruh

Washington University in St. Louis

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Jeffrey B. Stambough

Washington University in St. Louis

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Craig J. Della Valle

Rush University Medical Center

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