Nathan A. Mall
Rush University Medical Center
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American Journal of Sports Medicine | 2014
Nathan A. Mall; Peter N. Chalmers; Mario Moric; Miho J. Tanaka; Brian J. Cole; Bernard R. Bach; George A. Paletta
Background: Anterior cruciate ligament (ACL) injury is among the most commonly studied injuries in orthopaedics. The previously reported incidence of ACL injury in the United States has varied considerably and is often based on expert opinion or single insurance databases. Purpose: To determine the incidence of ACL reconstruction (ACLR) in the United States; to identify changes in this incidence between 1994 and 2006; to identify changes in the demographics of ACLR over the same time period with respect to location (inpatient vs outpatient), sex, and age; and to determine the most frequent concomitant procedures performed at the time of ACLR. Study Design: Descriptive epidemiological study. Methods: International Classification of Diseases, 9th Revision (ICD-9) codes 844.2 and 717.83 were used to search the National Hospital Discharge Survey (NHDS) and the National Survey of Ambulatory Surgery (NSAS) for the diagnosis of ACL tear, and the procedure code 81.45 was used to search for ACLR. The incidence of ACLR in 1994 and 2006 was determined by use of US Census Data, and the results were then stratified based on patient age, sex, facility, concomitant diagnoses, and concomitant procedures. Results: The incidence of ACLR in the United States rose from 86,687 (95% CI, 51,844-121,530; 32.9 per 100,000 person-years) in 1994 to 129,836 (95% CI, 94,993-164,679; 43.5 per 100,000 person-years) in 2006 (P = .015). The number of ACLRs increased in patients younger than 20 years and those who were 40 years or older over this 12-year period. The incidence of ACLR in females significantly increased from 10.36 to 18.06 per 100,000 person-years between 1994 and 2006 (P = .0003), while that in males rose at a slower rate, with an incidence of 22.58 per 100,000 person-years in 1994 and 25.42 per 100,000 person-years in 2006. In 2006, 95% of ACLRs were performed in an outpatient setting, while in 1994 only 43% of ACLRs were performed in an outpatient setting. The most common concomitant procedures were partial meniscectomy and chondroplasty. Conclusion: The incidence of ACLR increased between 1994 and 2006, particularly in females as well as those younger than 20 years and those 40 years or older. Research efforts as well as cost-saving measures may be best served by targeting prevention and outcomes measures in these groups. Surgeons should be aware that concomitant injury is common.
Journal of Bone and Joint Surgery, American Volume | 2010
Nathan A. Mall; H. Mike Kim; Jay D. Keener; Karen Steger-May; Sharlene A. Teefey; William D. Middleton; Georgia Stobbs; Ken Yamaguchi
BACKGROUND The purposes of this study were to identify changes in tear dimensions, shoulder function, and glenohumeral kinematics when an asymptomatic rotator cuff tear becomes painful and to identify characteristics of individuals who develop pain compared with those who remain asymptomatic. METHODS A cohort of 195 subjects with an asymptomatic rotator cuff tear was prospectively monitored for pain development and examined annually for changes in various parameters such as tear size, fatty degeneration of the rotator cuff muscle, glenohumeral kinematics, and shoulder function. Forty-four subjects were found to have developed new pain, and the parameters before and after pain development were compared. The forty-four subjects were then compared with a group of fifty-five subjects who remained asymptomatic over a two-year period. RESULTS With pain development, the size of a full-thickness rotator cuff tear increased significantly, with 18% of the full-thickness tears showing an increase of >5 mm, and 40% of the partial-thickness tears had progressed to a full-thickness tear. In comparison with the assessments made before the onset of pain, the American Shoulder and Elbow Surgeons scores for shoulder function were significantly decreased and all measures of shoulder range of motion were decreased except for external rotation at 90° of abduction. There was an increase in compensatory scapulothoracic motion in relation to the glenohumeral motion during early shoulder abduction with pain development. No significant changes were found in external rotation strength or muscular fatty degeneration. Compared with the subjects who remained asymptomatic, the subjects who developed pain were found to have significantly larger tears at the time of initial enrollment. CONCLUSIONS Pain development in shoulders with an asymptomatic rotator cuff tear is associated with an increase in tear size. Larger tears are more likely to develop pain in the short term than are smaller tears. Further research is warranted to investigate the role of prophylactic treatment of asymptomatic shoulders to avoid the development of pain and loss of shoulder function.
Journal of Bone and Joint Surgery, American Volume | 2012
Rick W. Wright; Corey S. Gill; Ling Chen; Robert H. Brophy; Matthew J. Matava; Matthew Smith; Nathan A. Mall
BACKGROUND Revision anterior cruciate ligament (ACL) reconstruction is believed to have an inferior outcome compared with primary ACL reconstruction. The available literature on the outcome of revision ACL reconstruction is sparse compared with that for primary reconstruction. The purpose of this systematic review was to test the hypothesis that the outcome of revision ACL reconstruction compares unfavorably with the historical outcome of primary ACL reconstruction. METHODS A systematic review of studies evaluating the outcome of revision ACL reconstructions with a minimum of two years of follow-up was performed. Pooled data were collected when appropriate and a mixed-effect-model meta-analysis was performed for important outcome measures that were reported in several studies (objective graft failure, Lysholm score, International Knee Documentation Committee [IKDC] subjective score, and IKDC objective score). Objective failure was defined as repeat revision, a side-to-side difference of >5 mm measured with use of a KT1000 arthrometer, or a pivot-shift grade of 2+ or 3+. RESULTS Twenty-one studies were included, and 863 of the 1004 patients in these studies had a minimum of two years of follow-up and were analyzed. The pooled mean age of the patients at the time of the revision procedure was 30.6 years, and 66% were male. Objective failure occurred in 13.7% ± 2.7% of the patients (95% confidence interval, 8.0% to 19.4%). The mean Lysholm score in 491 patients was 82.1 ± 3.3 (95% confidence interval, 74.6 to 89.5) according to a mixed-model meta-analysis. The mean IKDC subjective score in 202 patients was 74.8 ± 4.4 (95% confidence interval, 62.5 to 87.0). CONCLUSIONS Revision ACL reconstruction resulted in a worse outcome compared with primary ACL reconstruction. Patient-reported outcome scores were inferior to previously published results of primary ACL reconstruction, but these differences may not be clinically important. A dramatically elevated failure rate was noted after revision ACL reconstruction; this rate was nearly three to four times the failure rate in prospective series of primary ACL reconstructions.
Journal of Bone and Joint Surgery, American Volume | 2014
Peter N. Chalmers; Nathan A. Mall; Mario Moric; Seth L. Sherman; George P. Paletta; Brian J. Cole; Bernard R. Bach
BACKGROUND Anterior cruciate ligament (ACL) injury can lead to tibiofemoral instability, decreased functional outcomes, and degenerative joint disease. It is unknown whether ACL reconstruction alters this progression at long-term follow-up. METHODS A systematic literature review of the long-term results (minimum follow-up, more than ten years) after operative intra-articular reconstruction of ACL injuries and after nonoperative management was performed to compare (1) knee stability on physical examination, (2) functional and patient-based outcomes, (3) the need for further surgical intervention, and (4) radiographic outcomes. After application of selection criteria, forty patient cohorts with a mean of 13.9 ± 3.1 years of postoperative follow-up were identified. Twenty-seven cohorts containing 1585 patients had undergone reconstruction, and thirteen containing 685 patients had been treated nonoperatively. RESULTS Comparison of operative and nonoperative cohorts revealed no significant differences in age, sex, body mass index, or rate of initial meniscal injury (p > 0.05 for all). Operative cohorts had significantly less need for further surgery (12.4% compared with 24.9% for nonoperative, p = 0.0176), less need for subsequent meniscal surgery (13.9% compared with 29.4%, p = 0.0017), and less decline in the Tegner score (-1.9 compared with -3.1, p = 0.0215). A difference in pivot-shift test results was observed (25.5% pivot-positive compared with 46.6% for nonoperative) but did not reach significance (p = 0.09). No significant differences were seen in outcome scores (Lysholm, International Knee Documentation Committee [IKDC], or final Tegner scores) or the rate of radiographically evident degenerative joint disease (p > 0.05 for all). CONCLUSIONS At a mean of 13.9 ± 3.1 years after injury, the patients who underwent ACL reconstruction had fewer subsequent meniscal injuries, less need for further surgery, and significantly greater improvement in activity level as measured with the Tegner score. There were no significant differences in the Lysholm score, IKDC score, or development of radiographically evident osteoarthritis.
Arthroscopy | 2012
Jaskarndip Chahal; Geoffrey S. Van Thiel; Nathan A. Mall; Wendell Heard; Bernard R. Bach; Brian J. Cole; Gregory P. Nicholson; Nikhil N. Verma; Daniel B. Whelan; Anthony A. Romeo
PURPOSE Despite the theoretic basis and interest in using platelet-rich plasma (PRP) to improve the potential for rotator cuff healing, there remains ongoing controversy regarding its clinical efficacy. The objective of this systematic review was to identify and summarize the available evidence to compare the efficacy of arthroscopic rotator cuff repair in patients with full-thickness rotator cuff tears who were concomitantly treated with PRP. METHODS We searched the Cochrane Central Register of Controlled Trials, Medline, Embase, and PubMed for eligible studies. Two reviewers selected studies for inclusion, assessed methodologic quality, and extracted data. Pooled analyses were performed using a random effects model to arrive at summary estimates of treatment effect with associated 95% confidence intervals. RESULTS Five studies (2 randomized and 3 nonrandomized with comparative control groups) met the inclusion criteria, with a total of 261 patients. Methodologic quality was uniformly sound as assessed by the Detsky scale and Newcastle-Ottawa Scale. Quantitative synthesis of all 5 studies showed that there was no statistically significant difference in the overall rate of rotator cuff retear between patients treated with PRP and those treated without PRP (risk ratio, 0.77; 95% confidence interval, 0.48 to 1.23). There were also no differences in the pooled Constant score; Simple Shoulder Test score; American Shoulder and Elbow Surgeons score; University of California, Los Angeles shoulder score; or Single Assessment Numeric Evaluation score. CONCLUSIONS PRP does not have an effect on overall retear rates or shoulder-specific outcomes after arthroscopic rotator cuff repair. Additional well-designed randomized trials are needed to corroborate these findings. LEVEL OF EVIDENCE Level III, systematic review of Level I, II, and III studies.
Journal of Bone and Joint Surgery, American Volume | 2014
Nathan A. Mall; Miho J. Tanaka; Luke S. Choi; George A. Paletta
Several studies have noted that increasing age is a significant factor for diminished rotator cuff healing, while biomechanical studies have suggested the reason for this may be an inferior healing environment in older patients. Larger tears and fatty infiltration or atrophy negatively affect rotator cuff healing. Arthroscopic rotator cuff repair, double-row repairs, performing a concomitant acromioplasty, and the use of platelet-rich plasma (PRP) do not demonstrate an improvement in structural healing over mini-open rotator cuff repairs, single-row repairs, not performing an acromioplasty, or not using PRP. There is conflicting evidence to support postoperative rehabilitation protocols using early motion over immobilization following rotator cuff repair.
Journal of Shoulder and Elbow Surgery | 2014
Peter N. Chalmers; William Slikker; Nathan A. Mall; Anil K. Gupta; Zain Rahman; Daniel J. Enriquez; Gregory P. Nicholson
BACKGROUND Significant controversy surrounds optimal treatment of displaced 4-part proximal humeral fractures. Reverse total shoulder arthroplasty (RTSA) has recently been proposed as an alternative to hemiarthroplasty (HA) and open reduction-internal fixation (ORIF). Several authors have questioned the additional implant cost for RTSA. The purpose of this study was to compare outcomes and cost of RTSA, HA, and ORIF. MATERIALS AND METHODS We prospectively evaluated patients who underwent RTSA for displaced 3- and 4-part proximal humeral fractures and then retrospectively developed age- and sex-matched control groups with 3- and 4-part proximal humeral fractures who underwent HA and ORIF. Range of motion including active forward elevation and external rotation and time to achieve active forward elevation >90° were recorded. American Shoulder and Elbow Surgeons (ASES), Short-Form 12-item (SF-12), and Simple Shoulder Test (SST) scores were recorded. In addition, treatment cost was assessed by Medicare data and implant list prices. RESULTS This study enrolled 27 patients; 9 underwent RTSA, 9 HA, and 9 ORIF. Minimum follow-up was 1 year. No significant differences were seen in SST, ASES, or SF-12 scores. Significantly more patients achieved >90° of active forward elevation after RTSA (P = .012). RTSA provided significant cost savings to Medicare compared with HA and ORIF (P = .002.) CONCLUSION In this case-control study, RTSA appears to provide superior range of motion earlier and more predictably than HA and ORIF, with significant cost savings to Medicare.
Arthroscopy | 2013
Nathan A. Mall; Andrew S. Lee; Jaskarndip Chahal; Seth L. Sherman; Anthony A. Romeo; Nikhil N. Verma; Brian J. Cole
PURPOSE The purpose of this study was to systematically review the literature to better define the epidemiology, mechanism of injury, tear characteristics, outcomes, and healing of traumatic rotator cuff tears. A secondary goal was to determine if sufficient evidence exists to recommend early surgical repair in traumatic rotator cuff tears. METHODS An independent systematic review was conducted of evidence Levels I to IV. A literature search of PubMed, Medline, Embase, and Cochrane Collaboration of Systematic Reviews was conducted, with 3 reviewers assessing studies for inclusion, methodology of individual study, and extracted data. RESULTS Nine studies met the inclusion and exclusion criteria. Average patient age was 54.7 (34 to 61) years, and reported mean time to surgical intervention, 66 days (3 to 48 weeks) from the time of injury. The most common mechanism of injury was fall onto an outstretched arm. Supraspinatus was involved in 84% of tears, and infraspinatus was torn in 39% of shoulders. Subscapularis tears were present in 78% of injuries. Tear size was <3 cm in 22%, 3 to 5 cm in 36%, and >5 cm in 42%. Average active forward elevation improved from 81° to 150° postoperatively. The weighted mean postoperative UCLA score was 30, and the Constant score was 77. CONCLUSIONS Traumatic rotator cuff tears are more likely to occur in relatively young (age 54.7), largely male patients who suffer a fall or trauma to an abducted, externally rotated arm. These tears are typically large and involve the subscapularis, and repair results in acceptable results. However, insufficient data prevent a firm recommendation for early surgical repair. LEVEL OF EVIDENCE Level IV, systematic review Levels III and IV studies.
Arthroscopy | 2012
Jaskarndip Chahal; Nathan A. Mall; Peter B. MacDonald; Geoffrey S. Van Thiel; Brian J. Cole; Anthony A. Romeo; Nikhil N. Verma
PURPOSE The purpose of this study was to determine the efficacy of arthroscopic repair of full-thickness rotator cuff tears with and without subacromial decompression. METHODS We searched the Cochrane Central Register of Controlled Trials (third quarter of 2011), Medline (1948 to week 1 of September 2011), and Embase (1980 to week 37 of 2011) for eligible randomized controlled trials. Two reviewers selected studies for inclusion, assessed methodologic quality, and extracted data. Pooled analyses were performed by use of a random effects and relative risk model with computation of 95% confidence intervals. RESULTS We included 4 randomized trials and 373 patients. Methodologic quality was variable as assessed by the CLEAR NPT (Checklist to Evaluate a Report of a Non-pharmacological Trial) tool. One trial showed that there was no difference in disease-specific quality of life (Western Ontario Rotator Cuff questionnaire) between the 2 treatment groups. A meta-analysis of shoulder-specific outcome measures (American Shoulder and Elbow Surgeons or Constant scores) or the rate of reoperation between patients treated with subacromial decompression and those treated without it also showed no statistically significant differences. CONCLUSIONS On the basis of the currently available literature, there is no statistically significant difference in subjective outcome after arthroscopic rotator cuff repair with or without acromioplasty at intermediate follow-up. LEVEL OF EVIDENCE Level I, systematic review of Level I studies.
Arthroscopy | 2013
Peter N. Chalmers; Nathan A. Mall; Brian J. Cole; Nikhil N. Verma; Bernard R. Bach
PURPOSE Failure to anatomically reconstruct the femoral footprint can lead to rotational instability and clinical failure. Thus we sought to compare femoral tunnel drilling techniques, specifically anteromedial (AM) and transtibial (TT) methods, with respect to rotational stability. METHODS In this study we evaluated available scientific support for the ability of both techniques to achieve rotational stability of the knee through a systematic review of the literature for directly comparative biomechanical and clinical studies. RESULTS We identified 9 studies (5 clinical Level II or III studies and 4 cadaveric studies) that directly compared AM and TT techniques. Three cadaveric and 2 clinical studies showed superior rotational stability with the AM technique as compared with the TT technique, whereas 2 cadaveric studies and 1 clinical study were unable to show any similar differences. Two studies showed superior clinical outcomes with the AM technique, whereas 3 studies were unable to show any difference. CONCLUSIONS In this systematic review of clinical and biomechanical studies directly comparing AM and TT techniques for anterior cruciate ligament reconstruction (ACLR) in the literature, there are mixed results, with some studies finding superior rotational stability and clinical outcomes with the AM technique and some finding no difference. No studies showed significantly better results with the TT technique. This study shows that the AM portal technique for ACLR may be more likely to produce improved clinical and biomechanical outcomes but that the TT technique is capable of producing similar outcomes. LEVEL OF EVIDENCE Level III, systematic review of Level II and III studies plus cadaver studies.