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Stephen S Burkhart

Publications and source records attributed to Stephen S Burkhart.

14 recordsLinked to original sources
PubMed2003

The comma sign: An arthroscopic guide to the torn subscapularis tendon.

Subscapularis tears are becoming increasingly recognized as a cause of shoulder pain and disability. However, identifying the subscapularis tendon stump is often difficult during repair of chronic, retracted subscapularis tears that are scarred to the deltoid fascia. The authors have found the "comma sign," an arc formed by a portion of the superior glenohumeral ligament/coracohumeral ligament complex, to be a useful marker of the superolateral corner of the torn subscapularis tendon.

Arthroscopy↗
PubMed2003

The disabled throwing shoulder: spectrum of pathology Part I: pathoanatomy and biomechanics.

PROLOGUE: Several years ago, when we began to question microinstability as the universal cause of the disabled throwing shoulder, we knew that we were questioning a sacrosanct tenet of American sports medicine. However, we were comfortable in our skepticism because we were relying on arthroscopic insights, clinical observations, and biomechanical data, thereby challenging unverified opinion with science. In so doing, we assembled a unified concept of the disabled throwing shoulder that encompassed biomechanics, pathoanatomy, kinetic chain considerations, surgical treatment, and rehabilitation. In developing this unified concept, we rejected much of the conventional wisdom of microinstability-based treatment in favor of more successful techniques (as judged by comparative outcomes) that were based on sound biomechanical concepts that had been scientifically verified. Although we have reported various components of this unified concept previously, we have been urged by many of our colleagues to publish this information together in a single reference for easy access by orthopaedic surgeons who treat overhead athletes. We are grateful to the editors of Arthroscopy for allowing us to present our view of the disabled throwing shoulder. Part I: Pathoanatomy and Biomechanics is presented in this issue. Part II: Evaluation and Treatment of SLAP Lesions in Throwers will be presented in the May-June issue. Part III: The "SICK" Scapula, Scapular Dyskinesis, the Kinetic Chain, and Rehabilitation will be presented in the July-August issue. We hope you find it thought-provoking and compelling.

Adolescent↗
PubMedDate not supplied

Arthroscopic coracoplasty through the rotator interval.

Coracoid impingement has been increasingly recognized as a cause of shoulder pain. Although most decompressive techniques involve open anterior surgery, the arthroscopic treatment of such impingement has only rarely been reported. In this report, the authors describe an intra-articular method of coracoplasty through the rotator interval. This method is easier to perform than a subacromial approach and allows appropriate orientation of the coracoplasty in the plane of the subscapularis tendon.

Adult↗
PubMedDate not supplied

The twist-lock concept of tissue transport and suture fixation without knots: observations along the Hong Kong skyline.

PURPOSE: To evaluate the load to failure and the mode of failure of a novel suture anchor construct that does not require knots (the "twist-lock" construct) and to compare it with a standard suture anchor construct (Corkscrew; Arthrex, Naples, FL). TYPE OF STUDY: Biomechanical single-pull load-to-failure study comparing the twist-lock construct to the Corkscrew suture anchor construct. METHODS: The twist-lock construct is a suture anchor system that does not use knots, instead using 3 consecutive twists between suture limbs to enhance internal interference between the suture limbs. This system maximizes internal interference by 2 mechanically verifiable friction-multiplier mechanisms: the cable friction effect and the wedge effect. After theoretically verifying the strength characteristics of the twist-lock system, the authors tested and compared its strength in vitro to that of a standard screw-type suture anchor system (Corkscrew). Unicellular polyurethane, which has been shown to accurately mimic the properties of cancellous bone, was used for implantation of suture anchors for the purpose of comparing the load to failure of 10 identical constructs in each of the 2 anchor systems. Axial single-pull loading to failure was performed with an Instron 5565 testing machine (Instron, Canton, MA). RESULTS: The average load to failure for the twist-lock group was 137.2 N, and the average for the Corkscrew group was 123.0 N, a difference of 14.2 N. This study shows that the twist-lock anchors failed at a load that was 12% higher than that of the Corkscrew group (P =.02). CONCLUSION: The twist-lock system is a suture anchor system that achieves suture fixation of soft tissue to bone without the need to tie knots. It shows single-pull loads to failure that are significantly higher than those of a standard suture anchor system.

Equipment Design↗
PubMedDate not supplied

Arthroscopic subscapularis tendon repair: Technique and preliminary results.

PURPOSE: Our objective was to evaluate the preliminary results of 25 consecutive arthroscopic subscapularis tendon repairs. TYPE OF STUDY: Case series. METHODS: All 25 shoulders had longer than 3 months follow-up, with an average of 10.7 months (range, 3 to 48 months). The average age was 60.7 years (range, 41 to 78 years). The average time from onset of symptoms to surgery was 18.9 months (range, 1 to 72 months). The shoulders were evaluated using a modified UCLA score, Napoleon test, lift-off test, radiographs, and magnetic resonance imaging (MRI). Indications for surgery included clinical and/or MRI evidence of a rotator cuff tear. An arthroscopic suture anchor technique devised by the senior author (S.S.B.) was used for repair. RESULTS: UCLA scores increased from a preoperative average of 10.7 to a postoperative average of 30.5 (P <.0001). By UCLA criteria, excellent and good results were obtained in 92% of patients, with 1 fair and 1 poor result. Forward flexion increased from an average 96.3 degrees preoperatively to an average 146.1 degrees postoperatively (P =.0016). Eight of 9 patients with a positive Napoleon test had complete tears of the subscapularis. All 7 patients with a negative Napoleon test had a tear of the upper half only. The lift-off test could not be performed reliably due to pain or restricted motion in 19 of the 25 patients. Eight patients had isolated tears of the subscapularis. The remaining 17 patients had associated rotator cuff tears with an average total tear size of 5 x 8 cm. Ten patients had proximal migration of the humerus preoperatively. Eight of these 10 patients had durable reversal of proximal humeral migration following surgery. These 8 patients improved their overhead function from a preoperative "shoulder shrug" with attempted elevation of the arm to functional overhead use of the arm postoperatively. CONCLUSIONS: (1) The senior author has been able to consistently perform arthroscopic repair of torn subscapularis tendons, with good and excellent results, in 92% of patients. (2) The Napoleon test is useful in predicting not only the presence of a subscapularis tear, but also its general size. (3) Combined tears of the subscapularis, supraspinatus, and infraspinatus tendons are frequently associated with proximal humeral migration and loss of overhead function. Arthroscopic repair of these massive tears can produce durable reversal of proximal humeral migration and restoration of overhead function.

Adult↗
PubMedDate not supplied

Quantifying glenoid bone loss arthroscopically in shoulder instability.

PURPOSE: Our goal was to establish a consistent methodology for quantifying glenoid bone loss by arthroscopic means. TYPE OF STUDY: This study was an anatomic investigation of glenoid structure and its consistent anatomic landmarks as determined by arthroscopic means in live subjects and by direct measurement in fresh-frozen cadaver specimens. METHODS: We arthroscopically evaluated and measured the location of the bare spot of the glenoid in 56 subjects that had no evidence of instability (average age, 40 years). We also measured the exact location of the glenoid bare spot in 10 cadaver shoulders (average age, 76 years). RESULTS: The bare spot of the glenoid was a consistent reference point from which to determine glenoid bone loss because it was located almost exactly at the center of the circle that was defined by the articular margin of the inferior glenoid below the level of the midglenoid notch. The tightly clustered standard deviations of the bare spot measurements in both the live subjects and the cadaver specimens confirmed its consistent location. CONCLUSIONS: The glenoid bare spot can be used as a central reference point to quantify the percentage bone loss of the inferior glenoid. Such objective measurement of glenoid bone loss can be clinically useful to the surgeon in deciding whether bone grafting is necessary to restore stability to the shoulder with a bone-deficient glenoid.

Adolescent↗
PubMedDate not supplied

The bubble sign: an arthroscopic indicator of an intratendinous rotator cuff tear.

Intratendinous tears of the rotator cuff are, by definition, difficult to diagnose due to the absence of overt tendon disruption on both the bursal and articular surface of the rotator cuff. The authors describe the bubble sign, a bulging expansion of the rotator cuff tendon following injection of saline into the suspected lesion, as a useful indicator of an intratendinous tear of the rotator cuff.

Adult↗
PubMedDate not supplied

Current concepts in arthroscopic rotator cuff repair.

The interest in arthroscopic rotator cuff repair has increased exponentially over the last 5 years. Although the operative technique of repair continues to evolve, there are now several studies reporting excellent results after arthroscopic repair of rotator cuff tears. In this review, we focus on new concepts and techniques related to arthroscopic rotator cuff repair that have been recently introduced.

Arthroscopy↗