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Management of massive and irreparable rotator cuff tears
Neri, Brian R; Chan, Keith W; Kwon, Young W
Massive rotator cuff tears pose a distinct clinical challenge for the orthopaedist. In this review, we will discuss the classification, diagnosis, and evaluation of massive rotator cuff tears before discussing various treatment options for this problem. Nonoperative treatment has had inconsistent results and proven unsuccessful for chronic symptoms while operative treatment including debridement and partial and complete repairs have had varying degrees of success. For rotator cuff tears that are deemed irreparable, treatment options are limited. The use of tendon transfers in younger patients to reconstruct rotator cuff function and restore shoulder kinematics can be useful in salvaging this difficult problem.
PMID: 19487132
ISSN: 1058-2746
CID: 566882
Open reduction and internal fixation of capitellar fractures with headless screws. Surgical technique
Ruchelsman, David E; Tejwani, Nirmal C; Kwon, Young W; Egol, Kenneth A
BACKGROUND: The outcome of operatively treated capitellar fractures has not been reported frequently. The purpose of the present study was to evaluate the clinical, radiographic, and functional outcomes following open reduction and internal fixation of capitellar fractures that were treated with a uniform surgical approach in order to further define the impact on the outcome of fracture type and concomitant lateral column osseous and/or ligamentous injuries. METHODS: A retrospective evaluation of the upper extremity database at our institution identified sixteen skeletally mature patients (mean age, 40 +/- 17 years) with a closed capitellar fracture. In all cases, an extensile lateral exposure and articular fixation with buried cannulated variable-pitch headless compression screws was performed at a mean of ten days after the injury. Clinical, radiographic, and elbow-specific outcomes, including the Mayo Elbow Performance Index, were evaluated at a mean of 27 +/- 19 months postoperatively. RESULTS: Six Type-I, two Type-III, and eight Type-IV fractures were identified with use of the Bryan and Morrey classification system. Four of five ipsilateral radial head fractures occurred in association with a Type-IV fracture. The lateral collateral ligament was intact in fifteen of the sixteen elbows. Metaphyseal comminution was observed in association with five fractures (including four Type-IV fractures and one Type-III fracture). Supplemental mini-fragment screws were used for four of eight Type-IV fractures and one of two Type-III fractures. All fractures healed, and no elbow had instability or weakness. Overall, the mean ulnohumeral motion was 123 degrees (range, 70 degrees to 150 degrees ). Fourteen of the sixteen patients achieved a functional arc of elbow motion, and all patients had full forearm rotation. The mean Mayo Elbow Performance Index score was 92 +/- 10 points, with nine excellent results, six good results, and one fair result. Patients with a Type-IV fracture had a greater magnitude of flexion contracture (p = 0.04), reduced terminal flexion (p = 0.02), and a reduced net ulnohumeral arc (p = 0.01). An ipsilateral radial head fracture did not appear to affect ulnohumeral motion or the functional outcome. CONCLUSIONS: Despite the presence of greater flexion contractures at the time of follow-up in elbows with Type-IV fractures or fractures with an ipsilateral radial head fracture, good to excellent outcomes with functional ulnohumeral motion can be achieved following internal fixation of these complex fractures. Type-IV injuries may be more common than previously thought; such fractures often are associated with metaphyseal comminution or a radial head fracture and may require supplemental fixation
PMID: 19255199
ISSN: 1535-1386
CID: 93739
Atraumatic osteonecrosis of the humeral head
Gruson, Konrad I; Kwon, Young W
While much literature has focused on the management of osteonecrosis of the femoral head, far less information is available regarding the treatment and outcomes of this disease in the proximal humerus. To a great extent, management of humeral head osteonecrosis has been inferred from studies involving the femoral head. The etiologies for this disease can be categorized most usefully as traumatic versus atraumatic. Regardless of the underlying etiology, the common pathway involves disruption of the arterial inflow or the venous outflow of the bone, with resultant osseous cell death. The general treatment strategies for humeral head osteonecrosis include nonoperative modalities for symptomatic early disease, with surgical intervention reserved for more advanced disease or those with recalcitrant pain
PMID: 19302052
ISSN: 1936-9719
CID: 99280
Tendon transfers for irreparable rotator cuff tears
Neri, Brian R; Chan, Keith W; Kwon, Young W
PMID: 19302053
ISSN: 1936-9719
CID: 99281
Snapping scapula syndrome
Lazar, Meredith A; Kwon, Young W; Rokito, Andrew S
Snapping scapula syndrome arises from either a soft-tissue or a skeletal anomaly within the scapulothoracic space that creates a cracking sound during scapulothoracic motion that patients associate with pain. Nonoperative measures consisting of supervised physical therapy, anti-inflammatory medications, and therapeutic injections are the mainstay of treatment. Open, arthroscopic, and combined operative approaches have been described for the treatment of refractory cases, with good overall outcomes in many relatively small case series. However, the optimal operative approach has yet to be determined
PMID: 19724005
ISSN: 1535-1386
CID: 101965
Proximal biceps tendon--a biomechanical analysis of the stability at the bicipital groove
Kwon, Young W; Hurd, Jason; Yeager, Keith; Ishak, Charbel; Walker, Peter S; Khan, Sami; Bosco, Joseph A 3rd; Jazrawi, Laith M
The subscapularis tendon, coracohumeral ligament, and transverse humeral ligament are all believed to contribute to biceps tendon stability within the bicipital groove. In order to examine the relative contribution of these soft tissue structures to proximal biceps tendon stability, 11 fresh frozen cadaveric shoulder specimens were prepared and mounted onto a custom jig. A three-dimensional digitizer was utilized to record biceps tendon excursion in various shoulder positions. In sequential order, these structures were then sectioned, and biceps tendon excursion was again recorded. We found that sectioning of the subscapularis tendon significantly increased biceps tendon excursion, compared to intact specimens (8.1 +/- 4.1 mm vs. 4.3 +/- 3.6 mm; p < 0.006). In contrast, isolated sectioning of the transverse humeral ligament or the coracohumeral ligament did not significantly increase biceps excursion (5.4 +/- 2.5 mm, p = 0.26; 5.6 +/- 1.3 mm, p = 0.24). When two structures were sectioned, significant excursion in the biceps tendon only occurred in specimens where the subscapularis tendon was one of the sectioned structures. The preliminary data suggest that, of the three tested soft tissue structures, the subscapularis tendon is the most important stabilizer of the proximal biceps and that clinically significant lesions of the proximal biceps tendon may be associated with a defect in the subscapularis tendon
PMID: 20001935
ISSN: 1936-9727
CID: 105972
Normal glenoid vault anatomy and validation of a novel glenoid implant shape
Codsi, Michael J; Bennetts, Craig; Gordiev, Katherine; Boeck, Daniel M; Kwon, Young; Brems, John; Powell, Kimerly; Iannotti, Joseph P
Current glenoid implants are designed to be secured to the articular surface. When the articular surface is compromised, a glenoid component could be implanted if it obtained fixation from the endosteal surface of the glenoid vault. The first step for designing such a glenoid implant is to define the normal three-dimensional anatomy of the glenoid vault. The purpose of this study was to define the variations in glenoid vault shape in a large group of cadaver scapula. Computed tomographic (CT) scans of 61 normal scapulae (mean, 25-34 years) from the Haman-Todd Osteological Collection, with a wide range of sizes, were examined to define the normal glenoid vault anatomy. A custom software program was used to manipulate and measure the scans to determine the morphologic variations among the different glenoid vaults. From these data, we defined a unique glenoid vault shape and empirically developed 5 sizes to represent the study population of the 61 scapulae. A second group of 11 cadaver scapulae were used to validate the shape defined using the other 61. Prototype implants were placed into the real 11 scapulae using standard surgical techniques and then CT-scanned to analyze the shape of the glenoid vault. In the 61 scapulae, 85% of the points defining the endosteal surfaces vary among scapulae by less than 2 mm. For each of the 11 cadaver scapulae, the implant size used in the virtual computer implantation was the same size used for the plastic components placed into the cadaver scapulae. Fifty percent of the measured distances between the outer dimensions of the plastic models was within 2.4 mm of the glenoid endosteal surface. Eighty percent of the surface area of the plastic models was within 3.1 mm of the glenoid endosteal surface. Five percent of the dimensions were less than 1 mm and were considered to be areas of point contact. Before designing implants that can be used in pathologic glenoids, the shape of the normal glenoid vault must first be defined. This study defined a normal glenoid vault shape that can accommodate different sized scapula with 5 sizes. This glenoid shape may be used as a template to design a glenoid implant that obtains fixation within the glenoid vault.
PMID: 18328741
ISSN: 1058-2746
CID: 566952
Open reduction and internal fixation of capitellar fractures with headless screws
Ruchelsman, David E; Tejwani, Nirmal C; Kwon, Young W; Egol, Kenneth A
BACKGROUND: The outcome of operatively treated capitellar fractures has not been reported frequently. The purpose of the present study was to evaluate the clinical, radiographic, and functional outcomes following open reduction and internal fixation of capitellar fractures that were treated with a uniform surgical approach in order to further define the impact on the outcome of fracture type and concomitant lateral column osseous and/or ligamentous injuries. METHODS: A retrospective evaluation of the upper extremity database at our institution identified sixteen skeletally mature patients (mean age, 40 +/- 17 years) with a closed capitellar fracture. In all cases, an extensile lateral exposure and articular fixation with buried cannulated variable-pitch headless compression screws was performed at a mean of ten days after the injury. Clinical, radiographic, and elbow-specific outcomes, including the Mayo Elbow Performance Index, were evaluated at a mean of 27 +/- 19 months postoperatively. RESULTS: Six Type-I, two Type-III, and eight Type-IV fractures were identified with use of the Bryan and Morrey classification system. Four of five ipsilateral radial head fractures occurred in association with a Type-IV fracture. The lateral collateral ligament was intact in fifteen of the sixteen elbows. Metaphyseal comminution was observed in association with five fractures (including four Type-IV fractures and one Type-III fracture). Supplemental mini-fragment screws were used for four of eight Type-IV fractures and one of two Type-III fractures. All fractures healed, and no elbow had instability or weakness. Overall, the mean ulnohumeral motion was 123 degrees (range, 70 degrees to 150 degrees). Fourteen of the sixteen patients achieved a functional arc of elbow motion, and all patients had full forearm rotation. The mean Mayo Elbow Performance Index score was 92 +/- 10 points, with nine excellent results, six good results, and one fair result. Patients with a Type-IV fracture had a greater magnitude of flexion contracture (p = 0.04), reduced terminal flexion (p = 0.02), and a reduced net ulnohumeral arc (p = 0.01). An ipsilateral radial head fracture did not appear to affect ulnohumeral motion or the functional outcome. CONCLUSIONS: Despite the presence of greater flexion contractures at the time of follow-up in elbows with Type-IV fractures or fractures with an ipsilateral radial head fracture, good to excellent outcomes with functional ulnohumeral motion can be achieved following internal fixation of these complex fractures. Type-IV injuries may be more common than previously thought; such fractures often are associated with metaphyseal comminution or a radial head fracture and may require supplemental fixation
PMID: 18519327
ISSN: 1535-1386
CID: 79388
Coronal plane partial articular fractures of the distal humerus: current concepts in management
Ruchelsman, David E; Tejwani, Nirmal C; Kwon, Young W; Egol, Kenneth A
Partial articular fractures of the distal humerus commonly involve the capitellum and may extend medially to involve the trochlea. As the complex nature of capitellar fractures has become better appreciated, treatment options have evolved from closed reduction and immobilization and fragment excision to a preference for open reduction and internal fixation. The latter is now recommended to achieve stable anatomic reduction, restore articular congruity, and initiate early motion. More complex fracture patterns require extensile surgical exposures. The fractures are characterized by metaphyseal comminution of the lateral column and have associated ipsilateral radial head fracture. With advanced instrumentation, elbow arthroscopy may be used in the management of these articular fractures. Though limited to level IV evidence, clinical series reporting outcomes following open reduction and internal fixation of fractures of the capitellum, with or without associated injuries, have demonstrated good to excellent functional results in most patients when the injury is limited to the radiocapitellar compartment. Clinically significant osteonecrosis and heterotopic ossification are rare, but mild to moderate posttraumatic osteoarthrosis may be anticipated at midterm follow-up
PMID: 19056920
ISSN: 1067-151x
CID: 91337
Three-dimensional motion of the scapula and shoulder during activities of daily living
Sheikhzadeh, Ali; Yoon, Jangwhon; Pinto, Vivek J; Kwon, Young W
The purpose of this study was to describe 3-dimensional scapular motion during the activities of daily living (ADL) and the full range of arm motion, and to suggest a standardized method for evaluating scapular mobility. Eight healthy subjects between the ages of 25-40, with no prior history of shoulder pathology or surgery for the past 12 months, were recruited for this study. Touching 8 predetermined landmarks on the head and the trunk was used to simulate ADL. Touching the contralateral ear and contralateral shoulder resulted in the maximum scapular protraction 46 degrees (8 degrees) and 48 degrees (8 degrees), respectively, and the maximum degrees of the scapular anterior tilt, -11 degrees (4 degrees) and -11 degrees (5 degrees), respectively. Asking patients to reach to the back of the neck, and the contralateral shoulder, the clinician can evaluate the overall scapular mobility in all directions. A protocol controlling the performance variability during ADL tasks was suggested to improve the clinical evaluation of the shoulder joint complex. Findings of this study can guide clinicians to identify specific tasks which may relate to particular shoulder girdle dysfunction
PMID: 18774735
ISSN: 1532-6500
CID: 93940