Sang-Jin Shin

Prognostic factors for unstable proximal humeral fractures treated with locking-plate fixation.

This study evaluated the functional outcomes of proximal humeral fractures treated with locking plates and determined the prognostic factors for successful clinical outcomes. We included 44 patients with 45 unstable proximal humeral fractures. There were 19 two-part, 22 three-part, and 4 four-part fractures. Outcomes were analyzed by use of multivariate linear regression with several different combinations of 7 independent variables: age, fracture pattern, osteoporosis, calcium sulfate graft, rotator cuff suture loop, head-neck shaft angle, and comorbidity. The mean head-shaft angle was 132.4 degrees after the operation and decreased to 127.7 degrees at final follow-up. Five patients showed considerable loss of fixation. The analysis showed that delay in rehabilitation because of comorbidities and decreased head-neck shaft angle induced by lack of medial support were the primary prognostic factors that led to poor outcomes. The absence of comorbidity and the restoration of the medial metaphysis were the most reliable predictors of successful clinical outcomes.

A clinical comparison of two different double plating methods for intraarticular distal humerus fractures

BACKGROUND This study compared clinical outcomes in patients with intraarticular distal humerus fractures treated using 2 different double plating methods. METHOD Seventeen patients were treated by perpendicular plating (group I) and 18 by parallel plating (group II) methods. Arc of flexion averaged 106 degrees +/-23 degrees in group I and 112 degrees +/-19 degrees in group II. RESULTS Eleven patients in group I recovered full arc of flexion and 13 patients in group II achieved full arc of flexion. All patients obtained bone union, except 2 patients in group I. Nonunion in these patients developed in the supracondylar area. Complications developed in 6 patients in group I and in 8 in group II. No significant differences were found between the clinical outcomes of the 2o plating methods. CONCLUSION Although more patients failed to achieve bony union in the perpendicular plating group, both parallel and orthogonal plates positioning can provide adequate stability and anatomic reconstruction of the distal humerus fractures. LEVEL OF EVIDENCE 2.

The Efficacy of Acromioplasty in the Arthroscopic Repair of Small- to Medium-Sized Rotator Cuff Tears Without Acromial Spur: Prospective Comparative Study

PURPOSE To assess the role of acromioplasty in the arthroscopic repair of small- to medium-sized rotator cuff tears. METHODS A prospective randomized trial of 120 patients who had small- to medium-sized rotator cuff tears and various types of acromions without spurs were included. Sixty patients received arthroscopic rotator cuff repair with acromioplasty (group I), and another sixty received the same procedure without acromioplasty (group II). The mean age at surgery was 57.8 ± 9.3 years in group I and 55.8 ± 8.0 years in group II. The shape of the acromion was flat in 18 patients, curved in 32, and hooked in 10 in group I, and it was flat in 15 patients, curved in 36, and hooked in 9 in group II. The mean tear size was similar in the two groups (14.6 ± 5.2 mm in group I and 15.3 ± 7.0 mm in group II). Pain and satisfaction were estimated and range of motion was measured at a mean of 35 months after surgery. Functional outcomes were assessed with American Shoulder and Elbow Surgeons: Constant; and University of California, Los Angeles scores. Tendon healing was evaluated by magnetic resonance imaging postoperatively. RESULTS Clinical outcome was significantly improved in both groups after arthroscopic rotator cuff repair (P < .05). There were no significant differences with respect to pain and range of motion between the groups at the final follow-up (1.1 ± 0.9 v 1.3 ± 1.4 on visual analog scale). Functional outcomes also showed no significant differences between the 2 groups (American Shoulder and Elbow Surgeons score, 90.7 ± 13.1 v 87.5 ± 12.0; Constant score, 85.0 ± 11.3 v 83.3 ± 13.0; and University of California, Los Angeles score, 33.4 ± 3.3 v 32.3 ± 3.5). Postoperative imaging showed that the retear rate was 17% in group I and 20% in group II (P = .475). CONCLUSIONS Arthroscopic repair of small- to medium-sized rotator cuff tears provided pain relief and improved functional outcome with or without acromioplasty. Clinical outcomes were not significantly different, and acromioplasty may not be necessary in the operative treatment of patients with small- to medium-sized rotator cuff tears in the absence of acromial spurs. LEVEL OF EVIDENCE Level II, prospective comparative study.

The development and validation of an appraisal method for rotator cuff disorders: The Korean Shoulder Scoring System

HYPOTHESIS The purpose of this study was to develop and validate a disease-specific appraisal method for patients with rotator cuff disorders. The Korean Shoulder Scoring System (KSS) includes 5 domains totalling 100 points: function, 30 points; pain, 20; satisfaction, 10; range of motion, 20; and muscle power, consisting of strength, 10; and endurance, 10. METHOD The KSS was used to evaluate clinical outcomes of 430 patients with rotator cuff disorder for a period of 6 months postoperatively. RESULT The KSS had an acceptable level of internal consistency (alpha = 0.840). The KSS scores also correlated strongly with the Constant scores (r = 0.802), but less so with the American Shoulder and Elbow Surgeons scores (r = 0.602) and the University of California Los Angeles shoulder scores (r = 0.573). A large effect size (r = 1.234) and a standardized response mean (r = 1.317) for KSS were evident at 6 months postoperatively. CONCLUSION The KSS is a useful measurement tool that combines subjective and objective evaluations for shoulder function related to rotator cuff disorders.

Minimally invasive plate osteosynthesis of humeral shaft fractures: a technique to aid fracture reduction and minimize complications.

Objectives: To introduce a modified operative technique for minimally invasive plate osteosynthesis (MIPO) for acute displaced humeral shaft fractures and to evaluate the clinical and radiological outcomes. Design: Prospective clinical series study. Setting: University hospital. Patients: Twenty-one patients with acute displaced humeral shaft fractures were treated by MIPO with a modified fracture reduction technique. Intervention: A narrow 4.5/5.0-mm locking compression plate was applied to the anterior aspect of the humerus. Fracture reduction and manipulation were performed using a plate and drill bits. Main Outcome Measurements: The operating time, time to union, humeral alignment, and functional outcome of the shoulder and elbow joints were evaluated using the University of California Los Angeles shoulder score and Mayo elbow performance score. Results: No patient experienced a neurological complication. Bony union was obtained in 20/21 patients at a mean 17.5 weeks postoperatively. Eighteen patients had excellent and 3 patients had good results in the University of California Los Angeles score. The average Mayo elbow performance score was 97.5. Two patients were converted to an open reduction during operation due to a failure of MIPO. There was 1 nonunion and 1 malunion in this series. Conclusions: Although the MIPO technique for humeral shaft fractures is technically demanding, satisfactory clinical outcomes in terms of bony union and shoulder and elbow function can be obtained using the modified fracture reduction method. Potential postoperative complications, such as malreduction and nonunion, must be considered. Appropriate surgical indications, a thorough understanding of the neurovascular anatomy and skillful surgical technique, are needed to reduce potential complications. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Biomechanical effects of humeral neck-shaft angle and subscapularis integrity in reverse total shoulder arthroplasty

BACKGROUND The variability in functional outcomes and the occurrence of scapular notching and instability after reverse total shoulder arthroplasty remain problems. The objectives of this study were to measure the effect of reverse humeral component neck-shaft angle on impingement-free range of motion, abduction moment, and anterior dislocation force and to evaluate the effect of subscapularis loading on dislocation force. METHODS Six cadaveric shoulders were tested with 155°, 145°, and 135° reverse shoulder humeral neck-shaft angles. The adduction angle at which bone contact occurred and the internal and external rotational impingement-free range of motion angles were measured. Glenohumeral abduction moment was measured at 0° and 30° of abduction, and anterior dislocation forces were measured at 30° of internal rotation, 0°, and 30° of external rotation with and without subscapularis loading. RESULTS Adduction deficit angles for 155°, 145°, and 135° neck-shaft angle were 2° ± 5° of abduction, 7° ± 4° of adduction, and 12° ± 2° of adduction (P < .05). Impingement-free angles of humeral rotation and abduction moments were not statistically different between the neck-shaft angles. The anterior dislocation force was significantly higher for the 135° neck-shaft angle at 30° of external rotation and significantly higher for the 155° neck-shaft angle at 30° of internal rotation (P < .01). The anterior dislocation forces were significantly higher when the subscapularis was loaded (P < .01). CONCLUSIONS The 155° neck-shaft angle was more prone to scapular bone contact during adduction but was more stable at the internally rotated position, which was the least stable humeral rotation position. Subscapularis loading gave further anterior stability with all neck-shaft angles at all positions.

Risk factors for postoperative complications of displaced clavicular midshaft fractures.

BACKGROUND: This study evaluated the risk factors of the complications following operative treatment of an acute displaced clavicular midshaft fracture using a reconstruction plate. METHODS: One hundred twenty-five patients with an acute displaced clavicular midshaft fracture underwent open reduction and plate fixation using a reconstruction plate. Cerclage wires or interfragmentary screws were used for additional comminuted fragment fixation. Clinical outcomes and radiologic evaluation were assessed. Risk factors for postoperative complications requiring reoperation were analyzed by univariate analysis. RESULTS: Bony union was achieved in 110 patients without any complications within 10.6 weeks postoperatively. Fifteen patients (12%) had a complication requiring reoperation. Implant-related complications occurred in 10 patients (plate breakage in 6 and plate loosening in 4). Deep infection and intractable adhesive capsulitis occurred in one and two patients, respectively. Refracture of the same clavicle after plate removal occurred in two patients. All patients with plate breakage demonstrated nonunion at the time of second operation. Unlike plate breakage, plate loosening was found to be associated with technical errors. Preoperative fracture pattern (p = 0.012) and usage of cerclage wires for additional fragment fixation were found to be significantly related to implant failure (p = 0.009). CONCLUSIONS: Open reduction and internal fixation using a reconstruction plate for acute displaced clavicular midshaft fractures demonstrated satisfactory clinical outcomes and favorable bony union rates. However, hardware-related complications because of fracture pattern, nonunion, and inadequate surgical techniques require detailed consideration. Furthermore, when additional fixation is needed for comminuted fracture fragments, interfragmentary screw fixation is recommended before cerclage wiring. LEVEL OF EVIDENCE: III.

Critical Value of Anterior Glenoid Bone Loss That Leads to Recurrent Glenohumeral Instability After Arthroscopic Bankart Repair

Background: Generally, a glenoid bone loss greater than 20% to 25% is considered critical for poor surgical outcomes after a soft tissue repair. However, recent studies have suggested that the critical value should be lower. Purpose: To determine the critical value of anterior glenoid bone loss that led to surgical failure in patients with anterior shoulder instability. Study Design: Case-control study; Level of evidence, 3. Methods: The study included 169 patients with anterior glenoid erosion. The percentage of glenoid erosion was calculated as the ratio of the glenoid loss width and the glenoid width to the diameter of the outer-fitting circle based on the inferior portion of the glenoid contour. The critical value of the glenoid bone loss was analyzed by means of receiver operating characteristic (ROC) curve analysis. Patients were divided into 2 groups based on the amount of glenoid bone loss: group A (less than the critical value) and group B (more than the critical value). Patients evaluated their shoulder function as a percentage of their preinjury level using the Single Assessment Numeric Evaluation (SANE) score, and postoperative clinical outcomes were assessed with the American Shoulder and Elbow Surgeons (ASES) score and Rowe score. Surgical failure was defined as the need for revision surgery or the presence of subjective symptoms of instability. Results: The optimal critical value of glenoid bone loss was 17.3% (area under the curve = 0.82; 95% confidence interval, 0.73-0.91; P < .001; sensitivity 75%; specificity 86.6%). Group A and B contained 134 and 35 patients, respectively. Shoulder functional scores were significantly lower in group B than in group A (P < .001). Five patients (3.7%) in group A and 15 (42.9%) in group B had surgical failure (P < .001). The SANE score was significantly lower in group B (83.8 ± 12.1) than in group A (92.9 ± 4.7, P = .001). Conclusion: An anterior glenoid bone loss of 17.3% or more with respect to the longest anteroposterior glenoid width should be considered as the critical amount of bone loss that may result in recurrent glenohumeral instability after arthroscopic Bankart repair.

A surgical technique for minimally invasive plate osteosynthesis of clavicular midshaft fractures.

This study describes a minimally invasive plate osteosynthesis technique to treat acute displaced clavicular midshaft fractures using anterior-inferior plating. The technique assesses the fracture via a medial window and a lateral window without opening the fracture area itself. A 3.5-mm locking reconstruction plate is applied to fix the clavicle fracture, and reduction is achieved with a joystick technique using 2 threaded k-wires. The clinical outcomes of 19 patients with clavicle midshaft fractures treated using this technique are also described.

Clinical Outcomes of Modified Mason-Allen Single-Row Repair for Bursal-Sided Partial-Thickness Rotator Cuff Tears Comparison With the Double-Row Suture-Bridge Technique

Background: Various repair techniques have been reported for the operative treatment of bursal-sided partial-thickness rotator cuff tears. Recently, arthroscopic single-row repair using a modified Mason-Allen technique has been introduced. Hypothesis: The arthroscopic, modified Mason-Allen single-row technique with preservation of the articular-sided tendon provides satisfactory clinical outcomes and similar results to the double-row suture-bridge technique after conversion of a partial-thickness tear to a full-thickness tear. Study Design: Cohort study; Level of evidence, 3. Methods: A retrospective study was conducted on 84 consecutive patients with symptomatic, bursal-sided partial-thickness rotator cuff tears involving more than 50% thickness of the tendon. A total of 47 patients were treated by the modified Mason-Allen single-row repair technique, preserving the articular-sided tendon, and 37 patients were treated by the double-row suture-bridge repair technique after conversion to a full-thickness tear. The clinical and functional outcomes were evaluated using the American Shoulder and Elbow Surgeons (ASES) and Constant scores and a visual analog scale (VAS) for pain and satisfaction of patients. Magnetic resonance imaging (MRI) was used to analyze the integrity of tendons at 6-month follow-up. Patients were followed up for a mean of 32.5 months. Results: In the 47 patients treated with the modified Mason-Allen suture technique, the VAS score decreased from a preoperative mean of 5.3 ± 0.3 to 0.9 ± 0.5 at the time of final follow-up. There was a statistically significant increase in the mean ASES score (from 45.4 ± 2.9 to 88.6 ± 4.5) and mean Constant score (from 66.9 ± 2.6 to 88.1 ± 2.4) (P < .001). Four of 47 patients (8.5%) demonstrated retears at 6-month postoperative MRI. There was no statistical difference in terms of functional outcomes and the retear rate compared with those of patients with the suture-bridge repair technique (3 patients, 8.1%). However, the mean number of suture anchors used in the patients with modified Mason-Allen suture repair (1.2 ± 0.4) was significantly fewer than that in the patients with suture-bridge repair (3.2 ± 0.4) (P < .01). Conclusion: The modified Mason-Allen single-row repair technique that preserved the articular-sided tendon provided satisfactory clinical outcomes in patients with symptomatic, bursal-sided partial-thickness rotator cuff tears. Despite a fewer number of suture anchors, the shoulder functional outcomes and retear rate in patients after modified Mason-Allen repair were comparable with those of patients who underwent double-row suture-bridge repair. Therefore, the modified Mason-Allen single-row repair technique using a triple-loaded suture anchor can be considered as an effective treatment in patients with bursal-sided partial-thickness rotator cuff tears.