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Journal of Bone and Joint Surgery, American Volume | 2010

Symptomatic progression of asymptomatic rotator cuff tears a prospective study of clinical and sonographic variables

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 | 2014

Thirty-five-Year Results After Charnley Total Hip Arthroplasty in Patients Less Than Fifty Years Old A Concise Follow-up of Previous Reports*

Jay D. Keener; John J. Callaghan; Devon D. Goetz; Douglas R. Pederson; Patrick M. Sullivan; Richard C. Johnston

Abstract: We report the updated results for a previously evaluated cohort of patients who were less than fifty years old when they underwent Charnley total hip arthroplasty with cement. The original cohort consisted of ninety-three total hip arthroplasties performed in sixty-nine patients. The patients were followed for a minimum of twenty-five years after surgery or until death. The present report describes the findings of the radiographic and functional follow-up, which was performed for forty-two of the forty-three living patients. At the time of the latest follow-up, twenty-nine (31%) of the ninety-three total hip replacements had been revised or removed. Eighteen acetabular and five femoral components were revised secondary to aseptic loosening. The combined prevalence of radiographic failure or revision because of aseptic loosening was 13% for the femoral components and 34% for the acetabular components. Comorbid medical conditions significantly hindered results on each functional subscale (p < 0.05). This study demonstrates the durability of cemented total hip replacements in a young patient population. Sixty-nine percent of the original hip replacements were functioning well at the latest follow-up examination or at the time of death, and only 5% required more than one revision arthroplasty. Level of Evidence: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.We report the updated results for a previously described cohort of patients who were less than fifty years old at the time of the index Charnley total hip arthroplasty with cement. The original cohort consisted of ninety-three consecutive hips in sixty-nine patients. The patients were followed for a minimum of thirty-five years after surgery or until death. At the latest follow-up evaluation, there were forty-one total hip replacements (44%) in thirty-two living patients. Thirty-four (37%) of the ninety-three total hip replacements in the original cohort had been revised or removed. Twenty acetabular (22%) and seven femoral (8%) components had been revised for aseptic loosening. Since the twenty-five-year follow-up, the average six-minute-walk distance decreased from 395 m to 171 m, and this decrease correlated with increasing comorbidity. This study demonstrates the durability of cemented total hip replacements in a young patient population. Although 63% (fifty-nine) of the ninety-three original hip replacements were functioning at the latest follow-up or at the time of death, a significant decrease in activity level was seen over time (p < 0.001). Of the forty-one original implants in the patients who were alive at the time of the thirty-five-year follow-up, only 46% (nineteen) were retained.


Journal of Bone and Joint Surgery, American Volume | 2009

Tendon Integrity and Functional Outcome After Arthroscopic Repair of High-Grade Partial-Thickness Supraspinatus Tears

Ganesh Kamath; Leesa M. Galatz; Jay D. Keener; Sharlene A. Teefey; William D. Middleton; Ken Yamaguchi

BACKGROUND Partial-thickness rotator cuff tears are a common cause of shoulder pain, yet the appropriate surgical treatment is controversial. In particular, very little information is available regarding rotator cuff integrity after operative repair. The purpose of this study was to evaluate the functional outcome and anatomic healing rate after arthroscopic repair of high-grade partial (>50%) thickness tears of the supraspinatus tendon. METHODS Forty-one consecutive patients (forty-two shoulders) who had undergone arthroscopic conversion of a partial-thickness rotator cuff tear to a full-thickness tear and subsequent repair were evaluated with ultrasound for evidence of rotator cuff healing. Clinical outcomes were assessed with use of validated outcomes measures, and all patients were reexamined by an independent observer. RESULTS The average patient age was fifty-three years. Thirty-seven (88%) of the forty-two shoulders had an intact rotator cuff repair seen on ultrasound at an average of eleven months postoperatively. The remaining five patients had a full-thickness defect in the tendon. The mean American Shoulder and Elbow Surgeons (ASES) score improved from 46.1 points preoperatively to 82.1 points at the time of follow-up. The overall rate of patient satisfaction was 93%. The average age of the patients with an intact rotator cuff was 51.8 years compared with 62.6 years for those with a persistent defect (p = 0.02). CONCLUSIONS Arthroscopic repair of high-grade partial-thickness rotator cuff tears results in a high rate of tendon healing. Patient age is an important factor in tendon healing.


Journal of Bone and Joint Surgery, American Volume | 2010

Location and initiation of degenerative rotator cuff tears: An analysis of three hundred and sixty shoulders

H. Mike Kim; Nirvikar Dahiya; Sharlene A. Teefey; William D. Middleton; Georgia Stobbs; Karen Steger-May; Ken Yamaguchi; Jay D. Keener

BACKGROUND It has been theorized that degenerative rotator cuff tears most commonly involve the supraspinatus tendon, initiating at the anterior portion of the supraspinatus insertion and propagating posteriorly. The purposes of this study were to determine the most common location of degenerative rotator cuff tears and to examine tear location patterns associated with various tear sizes. METHODS Ultrasonograms of 360 shoulders with either a full-thickness rotator cuff tear (272) or a partial-thickness rotator cuff tear (eighty-eight) were obtained to measure the width and length of the tear and the distance from the biceps tendon to the anterior margin of the tear. Tears were grouped on the basis of their size (anteroposterior width) and extent (partial or full-thickness). Each tear was represented numerically as a column of consecutive numbers representing the tear width and distance posterior to the biceps tendon. All tears were pooled to graphically represent the width and location of the tears within groups. Frequency histograms of the pooled data were generated, and the mode was determined for each histogram representing various tear groups. RESULTS The mean age (and standard deviation) of the 233 subjects (360 shoulders) was 64.7 +/- 10.2 years. The mean width and length of the tears were 16.3 +/- 12.1 mm and 17.0 +/- 13.0 mm, respectively. The mean distance from the biceps tendon to the anterior tear margin was 7.8 +/- 5.7 mm (range, 0 to 26 mm). Histograms of the various tear groups invariably showed the location of 15 to 16 mm posterior to the biceps tendon to be the most commonly torn location within the posterior cuff tendons. The histograms of small tears (a width of <10 mm) and partial-thickness tears showed similar distributions of tear locations, indicating that the region approximately 15 mm posterior to the biceps tendon may be where rotator cuff tears most commonly initiate. CONCLUSIONS Degenerative rotator cuff tears most commonly involve a posterior location, near the junction of the supraspinatus and infraspinatus. The patterns of tear location across multiple tear sizes suggest that degenerative cuff tears may initiate in a region 13 to 17 mm posterior to the biceps tendon.


Journal of Bone and Joint Surgery, American Volume | 2009

Proximal humeral migration in shoulders with symptomatic and asymptomatic rotator cuff tears.

Jay D. Keener; Anthony S. Wei; H. Mike Kim; Karen Steger-May; Ken Yamaguchi

BACKGROUND Proximal humeral migration is commonly seen in rotator-cuff-deficient shoulders. The specific effects of the size of the rotator cuff tear and of pain on glenohumeral kinematics have been poorly defined. The purpose of this study was to examine the influences of cuff tear size and pain, separately, on humeral migration in a series of patients with symptomatic and asymptomatic rotator cuff tears. METHODS Ninety-eight asymptomatic and sixty-two symptomatic shoulders were identified from a cohort of patients with unilateral shoulder pain related to rotator cuff disease. All shoulders underwent ultrasonographic evaluation of the rotator cuff and standardized radiographic evaluation. Humeral migration was measured by three observers using software-enhanced radiographic analysis. RESULTS There was no significant difference in rotator cuff tear size between the asymptomatic and symptomatic shoulders, although more tears involved the infraspinatus in the symptomatic group (p = 0.01). Proximal humeral migration was greater in the shoulders with a symptomatic tear than it was in those with an asymptomatic tear (p = 0.03). Tears that involved the infraspinatus resulted in more migration than did isolated supraspinatus tears in both the symptomatic (p = 0.01) and the asymptomatic shoulders (p = 0.03). When the symptomatic tears of > or =175 mm(2) were analyzed separately, the size of the tear was found to correlate strongly with humeral migration (p = 0.01). However, when the symptomatic tears that were <175 mm(2) were analyzed, neither tear size nor pain was found to have a significant relationship with migration. When the analysis was limited to full-thickness symptomatic tears of > or =175 mm(2), both pain (p = 0.002) and tear area (p = 0.0002) were found to have a significant effect on migration. Multivariate analysis showed that tear size (p = 0.01) was the strongest predictor of migration in symptomatic shoulders. CONCLUSIONS Proximal humeral migration correlates with rotator cuff tear size. Tears extending into the infraspinatus tendon are associated with greater humeral migration than is seen with isolated supraspinatus tears. Humeral migration resulting from symptomatic rotator cuff tears is greater than that resulting from asymptomatic tears. Additionally, there is a critical size for tendon tears resulting in humeral migration in painful shoulders. Although both pain and tear size influence glenohumeral kinematics in symptomatic shoulders, only tear size is an independent predictor of humeral migration.


Journal of Electromyography and Kinesiology | 2010

Head and shoulder posture affect scapular mechanics and muscle activity in overhead tasks

Charles A. Thigpen; Darin A. Padua; Lori A. Michener; Kevin M. Guskiewicz; Carol Giuliani; Jay D. Keener; Nicholas Stergiou

Forward head and rounded shoulder posture (FHRSP) is theorized to contribute to alterations in scapular kinematics and muscle activity leading to the development of shoulder pain. However, reported differences in scapular kinematics and muscle activity in those with forward head and rounded shoulder posture are confounded by the presence of shoulder pain. Therefore, the purpose of this study was to compare scapular kinematics and muscle activity in individuals free from shoulder pain, with and without FHRSP. Eighty volunteers were classified as having FHRSP or ideal posture. Scapular kinematics were collected concurrently with muscle activity from the upper and lower trapezius as well as the serratus anterior muscles during a loaded flexion and overhead reaching task using an electromagnetic tracking system and surface electromyography. Separate mixed model analyses of variance were used to compare three-dimensional scapular kinematics and muscle activity during the ascending phases of both tasks. Individuals with FHRSP displayed significantly greater scapular internal rotation with less serratus anterior activity, during both tasks as well as greater scapular upward rotation, anterior tilting during the flexion task when compared with the ideal posture group. These results provide support for the clinical hypothesis that FHRSP impacts shoulder mechanics independent of shoulder pain.


Journal of Bone and Joint Surgery, American Volume | 2009

Shoulder Strength in Asymptomatic Individuals with Intact Compared with Torn Rotator Cuffs

H. Mike Kim; Sharlene A. Teefey; Ari Zelig; Leesa M. Galatz; Jay D. Keener; Ken Yamaguchi

BACKGROUND Normative data are essential to the evaluation of shoulder function. The purposes of this study were to establish a normative database of isometric shoulder strength measured in asymptomatic individuals verified to have intact rotator cuffs and to determine the effect of asymptomatic rotator cuff tears on shoulder strength. METHODS Two hundred and thirty-seven volunteers with no shoulder pain or history of shoulder injury were screened with ultrasonography bilaterally for rotator cuff tears and then underwent isometric strength measurements for abduction in the scapular plane and external rotation. Statistical analysis was performed to evaluate the effect of age, body habitus, hand dominance, and the presence of a rotator cuff tear on shoulder strength. RESULTS Of the 237 volunteers, forty-one were found to have a torn rotator cuff in at least one shoulder. The prevalence of rotator cuff tears was 0% for the subjects between forty and forty-nine years old; 10%, between fifty and fifty-nine years old; 20%, between sixty and sixty-nine years old; and 40.7% for those seventy years old or older. Both abduction strength and external rotation strength in the male subjects showed an age-dependent decrease, whereas only abduction strength showed an age-dependent decrease in the female subjects. In multiple regression analysis, age and weight were the most important predictors of abduction strength and external rotation strength, respectively. In the shoulders with a large-to-massive full-thickness rotator cuff tear, abduction strength was significantly decreased (p = 0.007). Additionally, the ratio of abduction strength to external rotation strength was significantly decreased in the shoulders with a large-to-massive full-thickness tear compared with the shoulders with an intact rotator cuff (p < 0.001). CONCLUSIONS There is a high prevalence of rotator cuff tears in elderly asymptomatic individuals. Asymptomatic shoulders with a large-to-massive full-thickness rotator cuff tear have significantly decreased abduction strength. When there is a substantial decrease in abduction strength in relation to external rotation strength, the presence of an asymptomatic full-thickness tear should be suspected in that shoulder. Previous studies establishing normative values for isometric shoulder strength may have been skewed by the presence of asymptomatic rotator cuff tears in elderly subgroups.


Journal of Bone and Joint Surgery, American Volume | 2010

Revision Arthroscopic Rotator Cuff Repair: Repair Integrity and Clinical Outcome

Jay D. Keener; Anthony S. Wei; H. Mike Kim; Edward S. Paxton; Sharlene A. Teefey; Leesa M. Galatz; Ken Yamaguchi

BACKGROUND Literature regarding the outcomes of revision rotator cuff repair is limited. The purposes of the present study were to report the tendon repair integrity and clinical outcomes for a cohort of patients following revision arthroscopic rotator cuff repair and to examine factors related to tendon healing and the influence of healing on clinical outcomes. METHODS Twenty-one of twenty-nine consecutive revision arthroscopic rotator cuff repairs with a minimum of two years of postoperative follow-up were retrospectively reviewed. Outcomes were evaluated on the basis of a visual analog pain scale, the range of motion of the shoulder, the Simple Shoulder Test, the American Shoulder and Elbow Surgeons score, and the Constant score. Ultrasonography was used to examine repair integrity at a minimum of one year following surgery. Ten shoulders underwent arthroscopic repair of a recurrent single-tendon posterior rotator cuff tear, whereas eleven shoulders had repair of both the supraspinatus and infraspinatus. RESULTS The mean age of the twenty-one subjects was 55.6 years; thirteen subjects were male and eight were female. Complete preoperative and postoperative clinical data were available for nineteen subjects after an average duration of follow-up of thirty-three months. Significant improvements were seen in terms of postoperative pain (p < 0.05), the Simple Shoulder Test score (p < 0.05), the American Shoulder and Elbow Surgeons function (p < 0.05) and total scores (p < 0.05), active forward elevation (p < 0.05), and active external rotation (p < 0.05). Postoperative ultrasound data were available for all twenty-one shoulders after a mean duration of follow-up of twenty-five months. Ten (48%) of the twenty-one shoulders had an intact repair. Seven (70%) of the ten single-tendon repairs were intact, compared with three (27%) of the eleven supraspinatus/infraspinatus repairs (p = 0.05). Patient age (p < 0.05) and the number of torn tendons (p = 0.05) had significant effects on postoperative tendon repair integrity. Shoulders with an intact repair had better postoperative Constant scores (p < 0.05) and scapular plane elevation strength (p < 0.05) in comparison with those with a recurrent tear. CONCLUSIONS Revision arthroscopic rotator cuff repair results in reliable pain relief and improvement in shoulder function in selected cases. Approximately half of the revision repairs can be expected to be intact at a minimum of one year following surgery. Patient age and the number of torn tendons are related to postoperative tendon integrity. The postoperative integrity of the rotator cuff can have a significant influence on shoulder abduction strength and the Constant score.


Journal of Bone and Joint Surgery, American Volume | 2014

Rehabilitation Following Arthroscopic Rotator Cuff Repair: A Prospective Randomized Trial of Immobilization Compared with Early Motion

Jay D. Keener; Leesa M. Galatz; Georgia Stobbs-Cucchi; Rebecca Patton; Ken Yamaguchi

BACKGROUND The influence of rehabilitation on the outcomes after arthroscopic rotator cuff repair remains unknown. The purpose of this study was to compare clinical results and tendon healing rates following arthroscopic rotator cuff repair utilizing two distinct rehabilitation protocols. METHODS Over a thirty-month period, 124 patients under the age of sixty-five years underwent arthroscopic repair of a full-thickness rotator cuff tear measuring <30 mm in width. Postoperatively, patients were randomized either to a traditional rehabilitation program with early range of motion or to an immobilization group with delayed range of motion for six weeks. Clinical outcomes assessment included visual analog pain scale score, American Shoulder and Elbow Surgeons (ASES) score, Simple Shoulder Test (SST), relative Constant score, and strength measurements at six, twelve, and twenty-four months. Tendon integrity was assessed with ultrasonography at a minimum of twelve months postoperatively. RESULTS There were no significant differences in patient age, tear size, or measures of preoperative function between groups at baseline. Final clinical follow-up was available for 114 subjects (92%). Active elevation and external rotation were better in the traditional rehabilitation group at three months. No significant differences were seen in functional scores, active motion, and shoulder strength between rehabilitation groups at later time points. Functional outcomes plateaued at six or twelve months except for the relative Constant score, which improved up to twenty-four months following surgery. Ninety-two percent of the tears were healed, with no difference between rehabilitation protocols (p = 0.46). CONCLUSIONS Arthroscopic repair of small and medium full-thickness rotator cuff tears results in reliable improvements in clinical outcomes and a high rate of tendon integrity using a double-row repair technique in patients under the age of sixty-five years. There is no apparent advantage or disadvantage of early passive range of motion compared with immobilization with regard to healing or functional outcome.


Journal of Bone and Joint Surgery, American Volume | 2010

Relationship of Tear Size and Location to Fatty Degeneration of the Rotator Cuff

H. Mike Kim; Nirvikar Dahiya; Sharlene A. Teefey; Jay D. Keener; Leesa M. Galatz; Ken Yamaguchi

BACKGROUND Fatty degeneration of the rotator cuff muscles may have detrimental effects on both anatomical and functional outcomes following shoulder surgery. The purpose of this study was to investigate the relationship between tear geometry and muscle fatty degeneration in shoulders with a deficient rotator cuff. METHODS Ultrasonograms of both shoulders of 262 patients were reviewed to assess the type of rotator cuff tear and fatty degeneration in the supraspinatus and infraspinatus muscles. The 251 shoulders with a full-thickness tear underwent further evaluation for tear size and location. The relationship of tear size and location to fatty degeneration of the supraspinatus and infraspinatus muscles was investigated with use of statistical comparisons and regression models. RESULTS Fatty degeneration was found almost exclusively in shoulders with a full-thickness rotator cuff tear. Of the 251 shoulders with a full-thickness tear, eighty-seven (34.7%) had fatty degeneration in either the supraspinatus or infraspinatus, or both. Eighty-two (32.7%) of the 251 full-thickness tears had a distance of 0 mm between the biceps tendon and anterior margin of the tear. Ninety percent of the full-thickness tears with fatty degeneration in both muscles had a distance of 0 mm posterior from the biceps, whereas only 9% of those without fatty degeneration had a distance of 0 mm. Tears with fatty degeneration had significantly greater width and length than those without fatty degeneration (p < 0.0001). Tears with fatty degeneration had a significantly shorter distance posterior from the biceps than those without fatty degeneration (p < 0.0001). The distance posterior from the biceps was found to be the most important predictor for supraspinatus fatty degeneration, whereas tear width and length were found to be the most important predictors for infraspinatus fatty degeneration. CONCLUSIONS Fatty degeneration of the rotator cuff muscles is closely associated with tear size and location. The finding of this study suggests that the integrity of the anterior supraspinatus tendon is important to the development of fatty degeneration. Patients with full-thickness tears that extend through this area may benefit from earlier surgical intervention if fatty degeneration has not already occurred. Additionally, the findings suggest the importance of secure fixation and healing of the anterior aspect of the supraspinatus with surgical repair.

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Ken Yamaguchi

Washington University in St. Louis

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Aaron M. Chamberlain

Washington University in St. Louis

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Leesa M. Galatz

Icahn School of Medicine at Mount Sinai

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Peter N. Chalmers

Washington University in St. Louis

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Sharlene A. Teefey

Washington University in St. Louis

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Karen Steger-May

Washington University in St. Louis

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H. Mike Kim

Penn State Milton S. Hershey Medical Center

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Dane H. Salazar

Washington University in St. Louis

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Nathan D. Orvets

Washington University in St. Louis

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