Differences in Rupture Patterns and Associated Lesions Related to Traumatic Distal Triceps Tendon Rupture Between Outstretched Hand and Direct Injuries.

BACKGROUND: Traumatic distal triceps tendon rupture results in substantial disability in the absence of an appropriate diagnosis and treatment. To the best of our knowledge, differences in the degree of injury according to the injury mechanisms and associated lesions are not well known. QUESTIONS/PURPOSES: In this study, we asked: (1) What differences are seen in triceps tear patterns between indirect injuries (fall on an outstretched hand) and direct injuries? (2) What are the associated elbow and soft tissue injuries seen in indirect and direct triceps ruptures? METHODS: Between 2006 and 2017, one center treated 73 elbows of 72 patients for distal triceps tendon rupture. Of those, 70% (51 of 73 elbows) was excluded from this study; 8% (6 of 73) were related to systemic diseases, 59% (43 of 73) sustained open injuries, and 3% (2 of 73) were related to local steroid injections. We retrospectively collected data on traumatic distal triceps tendon rupture in 30% (22 of 73) of elbows at a single trauma center during a 10-year period. A fall on an outstretched hand was the cause of injury in 15 patients and direct blow by object or contusion were the cause in seven. MRI and surgery were performed in all patients. Traumatic distal triceps tendon rupture was classified by the Giannicola method, which is classified according to the depth and degree of the lesion based on MRI and surgical findings. Associated fractures and bone contusions on MRI were characterized. Ligament injuries on MRI was divided into partial and complete rupture. Agreement between the MRI and intraoperative findings for the presence of a traumatic distal triceps tendon rupture was perfect, and the Giannicola classification of traumatic distal triceps tendon rupture was good (kappa = 0.713). RESULTS: In the indirect injury group (fall on an outstretched hand), 15 of 15 patients had injuries that involved only the tendinous portion of the distal triceps, but these injuries were not full-thickness tears, whereas in the direct injury group, three of seven patients had a full-thickness rupture (odds ratio [OR] 1.75 [95% CI 0.92 to 3.32]; p = 0.02). The direct injury group had no associated ligamentous injuries while 14 of 15 patients with indirect injuries had ligamentous injuries (OR 0.13 [95% CI 0.02 to 0.78]; p < 0.001; associated injuries in the indirect group: anterior medial collateral ligament [14 of 15], posterior medial collateral ligament [7 of 15], and lateral collateral ligament complex [2 of 15]). Similarly, one of seven patients in the direct injury group had a bone injury (capitellar contusion), whereas 15 of 15 patients with indirect ruptures had associated fractures or bone contusions (OR 16.0 [95% CI 2.4 to 106.7]; p < 0.001). CONCLUSION: A fall on an outstretched hand may result in an injury mostly to the lateral and long head of distal triceps tendon and an intact medial head tendon; however, direct injuries can involve full-thickness ruptures. Although a traumatic distal triceps tendon rupture occurs after a fall on an outstretched hand, radial neck, capitellar, and medial collateral ligament injury can occur because of valgus load and remnant extensor mechanisms. Based on our finding, the clinician encountering a distal triceps tendon rupture due to a fall on an outstretched hand should be aware of the possibility of remaining elbow extensor mechanism by intact medial head tendon portion, and associated injuries, which may induce latent complications. LEVEL OF EVIDENCE: Level III, prognostic study.

Prediction of the anterior shoulder pain source by detecting indirect signs for partial articular subscapularis tendon tears through conventional magnetic resonance imaging.

PURPOSE: To evaluate the diagnostic efficacy of indirect signs for proximal articular-positioned, partial (< 50%), subscapularis tendon tears (facet 1 tears) via conventional magnetic resonance imaging (MRI). METHODS: A retrospective study was conducted on 67 patients of Yoo's type 1 or 2A tears. Forty-five arthroscopic subacromial decompression and acromioclavicular resection cases served as controls. Indirect signs indicating a facet 1 tear included small defects, superior subscapularis recess (SSR), long head of the biceps (LHBT) configurations, bone edema or cyst formation on lesser tuberosity (LTBEC), and fatty infiltration of subscapularis muscle. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were checked. RESULTS: SSR was the most sensitive sign (90%). The sensitivities and NPV of LHBT configurations and LTBEC were low (sensitivity: 42.9% and 17.9%, NPV: 56.4% and 44.4%, respectively). The specificities of all indirect signs were relatively high (> 90%). The Chi-squared test and multinomial logistic regression confirmed the significance of small defects, SSRs, and fatty infiltrations for facet 1 tears (p ≤ 0.014). The combined sensitivity and specificity were up to 97.7% and 92.3%, respectively, in the presence of either a small defect or an SSR. CONCLUSIONS: Conventional MRI alone can detect facet 1 tears through indirect signs (small defects, SSR, and fatty infiltrations of the subscapularis muscle), predicting unspecified anterior shoulder pain due to concealed biceps instability, and facilitating preoperative diagnosis for a facet 1 tear. LEVEL OF EVIDENCE: III.

Patterns of injury mechanism observed in terrible triad.

INTRODUCTION: The purpose of this study was to classify the injury mechanism of terrible triad (TT) and suggest a treatment method according to the mechanism. MATERIALS AND METHODS: Forty TTs with magnetic resonance imaging (MRI) scans and 3-dimensional computed tomography (3D CT) were enrolled. 3D CT scans of coronoid fractures were used for classifying into O'Driscoll type representing injury mechanisms and measuring sizes. In MRI scans, lateral collateral ligament complex (LCLC) injuries were classified into distraction (D) type caused by varus force and stripping (S) type caused by forearm external rotation force. Using these findings, possible injury mechanisms were speculated and classified into groups. Characteristic soft tissue injury patterns of collateral ligaments and overlying muscles, direction of dislocation in simple radiographs, and the amount of involvement of radial head fracture were investigated. Ulnar- and radial-side instabilities of soft tissues were newly defined and investigated. RESULTS: There were 29 (73%) cases by posterolateral external rotation (PLER), 5 (13%) cases by posteromedial external rotation (PMER), and 6 (14%) cases by posteromedial internal rotation (PMIR). Simple radiographs showed all posterolateral dislocations in PLER TT compared to posteromedial or pure posterior dislocations in PMER or PMIR TT. Regarding LCLC and overlying extensor muscle, they were all completely torn with D type in all PLER compared to D type in PMER or PMIR. The ulnar collateral ligament was spared in 5 (17%) cases among 29 PLER in contrast to complete rupture in all PMER and PMIR. In PLER, PMER, and PMIR, involvement ratios of radial head fracture were 82% (range, 27%-100%), 61% (range, 25%-100%), and 61% (range, 25%-100%), respectively, and sizes of coronoid fractures were 7 mm (range, 1-14 mm), 6 mm (range, 2-11 mm), and 10 mm (range, 2-16 mm), respectively. In PLER, PMER, and PMIR, percentages of ulnar-side instabilities were 17%, 20%, and 17%, respectively, and those of radial-side instabilities were 59%, 60%, and 83%, respectively. CONCLUSIONS: TT is caused by at least 3 mechanisms (PLER, PMER, and PMIR) with characteristic soft tissue injuries and fracture patterns. PLER is the main mechanism of injury. It is always observed in the form of posterolateral dislocation on simple radiographs compared with pure posterior or posteromedial dislocation of PMER or PMIR. It should be managed individually based on injury mechanisms presenting different instability patterns.

Soft tissue injury patterns in posteromedial rotatory instability with dislocation compared with posteromedial dislocation of the elbow joint.

BACKGROUND: We sought to determine injury mechanisms and soft tissue injury patterns of dislocation caused by posteromedial rotatory instability (PMRI) and simple posteromedial (PM) dislocation of the elbow joint that appear similar on simple radiographs. METHODS: In this retrospective case-series study, we reviewed 13 patients with PMRI dislocation and 10 patients with simple PM dislocation. Three-dimensional computed tomography and magnetic resonance imaging were performed in both groups. The ulnar collateral ligament, lateral collateral ligament complex (LCLC), overlying extensor muscle, and locus of bone contusion were identified. The direction of dislocation was categorized into the pure-posterior or PM type by simple radiographs. RESULTS: The LCLC was completely ruptured in both groups. A completely torn ulnar collateral ligament was observed in 3 patients (23%) in the PMRI dislocation group and 9 patients (90%) in the simple PM dislocation group (P = .005). Regarding injury patterns of the LCLC and overlying extensor muscle, the distraction type was found in 10 patients (77%) and the stripping type was found in 3 patients (23%) in the PMRI dislocation group, whereas all patients (100%) in the simple PM dislocation group had the distraction type (P = .103). Bone contusion was observed at the posterolateral olecranon in 2 patients (15%) in the PMRI dislocation group and at the PM olecranon in 4 patients (40%), posterolateral olecranon in 1 (10%), posterior olecranon in 1 (10%), and PM-posterolateral olecranon in 1 (10%) in the simple PM dislocation group (P = .008). In the PMRI dislocation group, 7 patients (54%) had the PM type and 6 (46%) had the pure-posterior type. CONCLUSIONS: Simple PM and PMRI dislocations of the elbow joint might have different soft tissue injury characteristics because of different injury mechanisms.

Dual reconstruction of lateral collateral ligament is safe and effective in treating posterolateral rotatory instability of the elbow.

PURPOSE: Although reconstruction of the lateral ulnar collateral ligament (LUCL) has been considered the procedure of choice for posterolateral rotatory instability (PLRI), recent studies have reported that the entire lateral collateral ligament complex (LCLC), rather than its posterior part only, contributes to preventing PLRI. Thus, it was hypothesized that dual reconstruction of the radial collateral ligament (RCL) and LUCL for the treatment of elbow PLRI could provide favourable clinical results regardless of the mechanism of injury. METHODS: This retrospective study reviewed the clinical results of 21 patients who underwent dual reconstruction of the RCL and LUCL between 2011 and 2016. Functional outcomes were assessed using the numeric rating scale (NRS) score, Mayo Elbow Performance Score (MEPS), quick Disabilities of the Arm, Shoulder, and Hand (quick DASH) score, and manual varus instability. To identify any difference in outcomes according to the aetiologies for LCLC insufficiency, our patients were divided into LCLC insufficiency associated with elbow dislocation and that with lateral epicondylitis. RESULTS: At a median follow-up of 27 months (range 13-65 months), all patients showed resolved instability and achieved a functional arc of motion. In addition, lateral pivot shift tests were negative in all patients. The median MEPS significantly improved after surgery from 70 (range 60-75) to 85 (range 75-100) (p < 0.001), while the median quick DASH score improved from 38.6 (range 26.6-54.5) to 11.4 (range 0-34.1) (p < 0.001). Clinical outcomes according to the aetiology of LCLC insufficiency were not significantly different except for the NRS score. CONCLUSION: The results suggest that the dual reconstruction technique leads to a clinical outcome similar to that of conventional LUCL reconstruction in LCLC insufficiency regardless of aetiology. In addition, the dual reconstruction technique was technically easier than the conventional LUCL reconstruction technique and may be a potential alternative when a bone tunnel created at the proximal ulna by the original technique has failed. LEVEL OF EVIDENCE: IV.

Treatment of posteromedial and posterolateral dislocation of the acute unstable elbow joint: a strategic approach.

BACKGROUND: The purpose of this study was to evaluate the different treatment strategies for posterolateral and posteromedial elbow dislocation. METHODS: The study enrolled 21 patients with unstable simple elbow dislocation including 16 cases of posterolateral dislocation (PLDL) and 5 cases of posteromedial dislocation (PMDL). In patients with PLDL, the medial side was evaluated and repaired first, followed by the lateral side. In patients with PMDL, the lateral side was repaired first, followed by the medial side according to residual instability. RESULTS: Among the 16 cases of unstable PLDL, 7 of 9 presenting with complex combined tear of the ulnar collateral ligament (UCL) and flexor muscle on magnetic resonance imaging showed abnormality on valgus stress testing and UCL repair. Three of 7 cases required additional lateral collateral ligament complex (LCLC) repair. Two of 9 cases showing medial complex dual lesions had normal findings on valgus stress testing and were treated only with LCLC repair. Seven of 16 cases without medial complex dual lesion had normal findings on valgus stress testing, and only LCLC repair was performed. All 5 cases of unstable PMDL showed distraction-type LCLC injury on magnetic resonance imaging and required no additional UCL repair after LCLC repair. There were no cases of recurrent instability following this treatment algorithm. CONCLUSIONS: In unstable elbow dislocation, PLDL and PMDL are caused by different mechanisms following damage to different structures. Therefore, different strategies are needed to ameliorate the dislocation and instability.

What Injury Mechanism and Patterns of Ligament Status Are Associated With Isolated Coronoid, Isolated Radial Head, and Combined Fractures?

BACKGROUND: Isolated coronoid, isolated radial head, and combined coronoid and radial head fractures are common elbow fractures, and specific ligamentous injury of each fracture configuration has been reported. However, the osseous injury mechanism related to ligament status remains unclear. QUESTIONS/PURPOSES: The objectives of this study were: (1) to determine what ligamentous injury patterns (medial or lateral collateral) and bone contusion patterns (medial or lateral) are associated with isolated coronoid, isolated radial head, and combined coronoid and radial head fractures; (2) to correlate the osseous injury mechanism based on these findings with isolated coronoid, isolated radial head, and combined coronoid and radial head fractures; and (3) to determine whether isolated and combined coronoid fractures have different fracture lines through the coronoid (tip or anteromedial facet), speculated to be caused by different injury mechanisms. METHODS: Between June 2007 and June 2012, 100 patients with elbow fractures were included in the cohort, with 46 of these patients being excluded owing to incongruity for our surgical indication. Finally, 54 patients with surgically treated elbow fractures who had MRI preoperatively were assessed retrospectively. There were 17 elbows with isolated coronoid fractures, 22 with isolated radial head fractures, and 15 with combined coronoid and radial head fractures. Collateral ligament injury pattern and existence of distal humerus bone contusion were reviewed on MR images. RESULTS: Patients with isolated radial head fractures were at greater risk of medial collateral ligament rupture compared with patients with isolated coronoid fractures (radial head only: 15 of 22 [68%]; coronoid only: three of 17 [18%]; odds ratio [OR], 10.0; 95% CI, 2.2-46.5; p = 0.002). Patients with isolated coronoid fractures had greater risk of lateral ulnar collateral ligament ruptures (coronoid: 16 of 17 [94%]; radial head: seven of 22 [32%]; OR, 3.5; 95% CI, 3.8-333.3; p < 0.001). The presence of radial head fractures was associated with the risk of lateral bone bruising (isolated radial head fracture: 32 of 37 [86%], isolated coronoid fracture: four of 17 [24%]; OR, 29.6; 95% CI, 5.2-168.9; p < 0.001). Medial bone bruising was only detected in isolated coronoid fractures (isolated coronoid fracture: 12 of 17 [71%], others: zero of 37 [0%]). All isolated coronoid fractures involved the anteromedial facet of the coronoid (17 of 17; 100%). However, combined coronoid and radial head fractures often involved the tip (13 of 15; 87%). CONCLUSIONS: Isolated coronoid fractures mostly involved the anteromedial facet of the coronoid process associated with lateral ulnar collateral ligament rupture and medial bone bruising. However, isolated radial head fractures were associated with medial collateral ligament rupture and lateral bone bruising. Combined coronoid and radial head fractures mostly involved a tip fracture of the coronoid with lateral ulnar collateral ligament rupture and lateral bone bruising. Thus surgeons may predict which ligament they should be aware of in the surgical field. LEVEL OF EVIDENCE: Level III, prognostic study.

Drop sign of the elbow joint after surgical stabilization of an unstable simple posterolateral dislocation: natural course and contributing factors.

BACKGROUND: We performed this study to investigate the natural course and factors affecting the incidence of drop sign immediately after stabilization of an unstable posterolateral (PL) dislocation of the elbow. METHODS: Twenty-three patients who underwent a stabilization procedure for persistent instability after closed reduction of PL dislocation of the elbow were enrolled. The natural course was evaluated with simple radiographs taken at regular intervals after the operation. Primary repair of medial or lateral ligaments and overlying muscles, degree of adjacent muscle injury, and type of anesthesia were analyzed to determine their relationship to postoperative drop sign. Functional outcomes were evaluated by the Disabilities of the Arm, Shoulder, and Hand score and Mayo Elbow Performance Score. RESULTS: A postoperative drop sign was observed in 4 cases (17%) and resolved within 1 week after the operation. There was no significant relationship between preoperative factors and drop sign except method of anesthesia. All drop signs were found in patients who had received a regional block (P = .006). There were no statistically significant differences in functional outcome between the drop sign group and the non-drop sign group. CONCLUSIONS: A postoperative drop sign was observed in 17% of patients who underwent a surgical stabilization procedure for an unstable PL elbow dislocation; this sign spontaneously disappeared in all 4 patients within 1 week of the operation. The drop sign was possibly caused by delayed return of muscle tone. A postoperative drop sign did not indicate the need to perform an additional stabilization procedure, nor did it affect postoperative functional outcome.

Strategic approach to O'Driscoll type 2 anteromedial coronoid facet fracture.

BACKGROUND: The purpose of this study was to suggest a strategic approach to the management of anteromedial coronoid facet (AMCF) fracture that is related to posteromedial rotational instability of the elbow through investigation of the surgical outcome of diverse combinations, including internal fixation of AMCF fractures and repair of collateral ligament injury. METHODS: The study enrolled 18 patients. On the basis of the size of the coronoid fracture and the degree of the soft tissue injuries that were evaluated with computed tomography, magnetic resonance imaging, and varus stress test under anesthesia, these fractures were managed differently. Functional outcomes were evaluated with the visual analog scale score, modified Mayo Elbow Performance Score, and Disabilities of the Arm, Shoulder and Hand score. Plain radiographs were used to evaluate the degree of arthrosis. RESULTS: There were 2 cases of O'Driscoll type 2, subtype 1 fractures; 14 cases of type 2, subtype 2 fractures; and 2 cases of type 2, subtype 3 fractures. Seven cases were managed with only AMCF fracture fixation, 4 cases with only lateral ulnar collateral ligament (LUCL) repair, 6 cases with concomitant repair of the LUCL and AMCF fracture, and 1 case with a conservative method. There were no significant differences among O'Driscoll types and among the subgroups of type 2-2 (P > .05). When the elbow showed instability on the varus stress test after AMCF fracture fixation, the soft tissue injuries of the lateral elbow were more severe (P =. 015). Arthrosis was not correlated with the patient's symptoms (P > .05). CONCLUSION: AMCF fracture can be treated by only AMCF fracture fixation, only LUCL repair, or a combination of these techniques, depending on the size of the AMCF fracture fragment and the degree of the lateral soft tissue injuries.

Pure varus posteromedial rotatory instability of the elbow: Radiographic findings, treatment, and outcomes.

INTRODUCTION: Although varus posteromedial rotatory instability (VPMRI) is a subtle elbow injury that involves anteromedial coronoid facet (AMCF) fracture and ligamentous injuries, treatment options and outcomes of VPMRI remains controversial. The aim of this study was to investigate radiographic findings, treatments, and outcomes of a large series of VPMRI. METHODS: We retrospectively reviewed 91 pure VPMRI cases with AMCF fracture (O'Driscoll classification anteromedial type) which were treated at 6 hospitals. Clinical and radiographic outcomes were investigated with a mean follow-up period of 46.8 months using the Mayo elbow performance score (MEPS), and the Quick Disabilities of the Arm, Shoulder and Hand (Quick-DASH) score, and serial plain radiographs. RESULTS: In AMCF fracture, there were 4 cases of subtype 1, 67 cases of subtype 2, and 20 cases of subtype 3. On MRI, complete tears of lateral collateral ligament and medial collateral ligament were observed in 83.1 % (59/71 cases) and 33.8 % (24/71 cases). Operative treatment was performed in 68 cases (74.7 %) including both side fixation in 40 cases (58.8 %), medial side fixation only in 17 cases (25.0 %), and lateral side fixation only in 11 cases (16.2 %). Nonoperative treatment was performed in 23 cases (25.3 %). The mean final MEPS and Quick-DASH scores were 93.7 and 7.9. The overall complication and reoperation rates were 22.0 % and 15.4 %. No significant differences regarding final clinical scores and range of motions were observed between the operative group and the nonoperative group, but significant differences were observed regarding number (p = 0.019) and displacement (p = 0.002) of coronoid fragment, and complication rate (p < 0.001) between the two groups. CONCLUSION: Depending on the pattern of coronoid fragment and the degree of ligamentous injuries, operative treatment of unstable VPMRI using various fixation techniques including coronoid fixation and ligament repair yielded satisfactory final clinical outcomes. However, surgeons should be aware of the high complication and reoperation rates after operative treatment. Stable VPMRI with AMCF fracture involving minimal displacement or small number of fragments can be treated nonoperatively.

Is posterior synovial plica excision necessary for refractory lateral epicondylitis of the elbow?

BACKGROUND: Arthroscopic treatments for lateral epicondylitis including débridement of the extensor carpi radialis brevis (ECRB) origin (Baker technique) or resection of the radiocapitellar synovial plica reportedly improve symptoms. However the etiology of the disease and the role of the plica remain unclear. QUESTIONS/PURPOSES: We asked if posterior radiocapitellar synovial plica excision made any additional improvement in pain or function after arthroscopic ECRB release. METHODS: We retrospectively reviewed 38 patients who had arthroscopic treatment for refractory lateral epicondylitis between November 2003 and October 2009. Twenty patients (Group A) underwent the Baker technique and 18 patients (Group B) underwent a combination of the Baker technique and posterior synovial plica excision. The minimum followup was 36 months (mean, 46 months; range, 36-72 months) for Group A and 25 months (mean, 30 months; range, 25-36 months) for Group B. Postoperatively we obtained VAS pain and DASH scores for each group. RESULTS: Two years postoperatively, we found no differences in the VAS pain score or DASH: the mean VAS pain scores were 0.3 points in Group A and 0.4 points in Group B, and the DASH scores were 5.1 points and 6.1 points respectively. CONCLUSIONS: The addition of débridement of the posterior synovial fold did not appear to enhance either pain relief or function compared with the classic Baker technique without decortication.

Collateral ligament injury in the displaced radial head and neck fracture: correlation with fracture morphology and management strategy to the torn ulnar collateral ligament.

BACKGROUND: The purpose of our study was to correlate the morphology of displaced radial head and neck (DRHN) fractures with associated ligament injuries and evaluate the outcomes of management of the torn ulnar collateral ligament (UCL). METHODS: Twenty-nine surgically treated patients presenting with a DRHN fracture were classified using the Charalambous classification by 3-dimensional computed tomography. Accordingly, the collateral ligament and overlying muscle injuries and bony contusions were investigated with magnetic resonance imaging. The valgus stress test was performed intraoperatively on 20 patients with magnetic resonance-confirmed complete UCL rupture. If there was no firm end point, the UCL was repaired (group B). The others were treated conservatively (group A). The Minnesota Elbow Performance Score and Disabilities of the Arm, Shoulder and Hand scores were used to measure patient outcome. RESULTS: There was a trend toward a higher incidence of complete UCL rupture in Charalambous type 3D and 4D fractures (P = .110) and complete lateral UCL rupture in Charalambous type 1D and 2D fractures (P = .126), although this was not statistically significant. Rupture of the overlying muscles was more common in group B than in group A (P < .05). Functional outcome between the 2 groups was not significantly different. CONCLUSIONS: DRHN fracture is always a complex fracture accompanied by collateral ligament injuries. Type 3D and 4D tended to have a higher association with UCL rupture compared with type 1D and 2D, types commonly associated with lateral UCL rupture. The magnetic resonance imaging-confirmed torn UCL could be managed conservatively if there was a firm end point on valgus stress test.

New mechanism of the posterior elbow dislocation.

PURPOSE: To suggest a new model on the most common kind of posterior elbow dislocation using MRI findings on acute elbow injuries. METHODS: Fifteen patients with simple elbow dislocation (Group A) and 19 patients sustaining pure ligament injuries (Group B) were enrolled in this study. Using MRI scans, bony contusion at radial head and posterior capitellum (lateral bone contusion) and medial aspect of the ulnohumeral joint (medial bone contusion) were investigated with the injury patterns of the collateral ligament and overlying muscles. In Group A, the injury patterns of the ulnar and lateral ulnar collateral ligaments were classified into distraction or stripping type; in Group B, into rupture or strain. Based on these findings, we speculated the injury mechanism of the elbow dislocation. RESULTS: In Group A, posterolateral (PL) dislocation was found in 12 cases of distractive ulnar collateral ligament type and stripping lateral ulnar collateral ligament type, where lateral bone contusion was found in 11 cases. Posteromedial (PM) dislocation was observed in only two cases of distraction type of the LUCL, where medial bone contusion was seen in two cases. In PL dislocation of the elbow joint, we always found more severe damage of soft tissue at the medial side of the elbow joint compared to the lateral side. Lateral bone contusion was speculated to be caused by bony abutment under pathologic forearm external rotation (PFER) and medial bone contusion, by bony abutment under varus stress. In Group B, the ulnar collateral ligament was more commonly injured than the lateral ulnar collateral ligament, and lateral bone contusion accompanied most cases. CONCLUSION: PL dislocation is thought to start from the medial side in contrary to PM dislocation beginning at the lateral side. If the disengagement of the coronoid process is not completed due to the insufficient valgus/varus distraction, a coronoid fracture will develop at the same time as the elbow dislocation during PFER.

Dual reconstruction of the radial collateral ligament and lateral ulnar collateral ligament in posterolateral rotator instability of the elbow.

Recent studies have found that the radial collateral ligament (RCL) plays a key role in the lateral stability of the elbow joint, and there is no truly isometric location for LUCL tendon graft reconstruction tunnels using the original technique. However, no report has been issued on the treatment including RCL reconstruction and the modification of LUCL reconstruction in patients with posterolateral rotatory instability (PLRI). Three patients with PLRI were treated using two different ways and produced good results. First, dual reconstruction of the LUCL and RCL was performed, and second, the insertion of the reconstructed LUCL was shifted to the AL instead of to the original ulna to produce a more flexible isometric point setting. We want to report on the management of PLRI by dual reconstruction of the RCL and LUCL and a modification of the original technique of LUCL reconstruction.

Rapid harvesting of stem cell sheets by thermoresponsive bulk poly(N-isopropylacrylamide) (PNIPAAm) nanotopography.

To date, cell sheet engineering-based technologies have actualized diverse scaffold-free bio-products to revitalize unintentionally damaged tissues/organs, including cardiomyopathy, corneal defects, and periodontal damage. Although substantial interest is now centered on the practical utilization of these bio-products for patients, the long harvest period of stem cells- or other primary cell-sheets has become a huge hurdle. Here, we dramatically reduce the total harvest period of a cell sheet (from cell layer formation to cell sheet detachment) composed of human bone marrow mesenchymal stem cells (hBMSCs) down to 2 d with the help of bulk thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) substrate nanotopography, which is not achievable via the previous grafting methods using PNIPAAm. We directly replicated an isotropic 400 nm-nanopore-array pattern on a bulk PNIPAAm substrate through UV polymerization of highly concentrated NIPAAm monomers, which was achieved using a remarkably increased Young's modulus of bulk PNIPAAm that was 1500 times higher than conventional PNIPAAm. The rapid harvesting of the hBMSC sheet on the bulk PNIPAAm substrate nanotopography was not only based on the accelerated formation and maturation of the hBMSC layer, but also the easy detachment of the hBMSC sheet induced by the abrupt change in the surface roughness of the substrate below the lower critical solution temperature (LCST) owing to the enlarged surface area of the substrate. Our findings may contribute to reverse presumptions about the limitations regarding the grafting methods for the cell sheet harvest and could broaden the practical utilization of cell sheets for patients in the near future.

A Case Series of Symptomatic Distal Biceps Tendinopathy.

BACKGROUND: The study of conservative and surgical treatment of distal biceps tendinopathy and associated biceps tendon partial rupture. METHODS: Twenty-one cases with distal biceps tendonitis and partial ruptures were studied who visited Pohang Semyeong Christianity Hospital from June 2010 to August 2017. The mean age was 57.1 years (39-69 years), 14 males and 7 females. The mean duration of symptom at the time of first visit was 4.9 months (0.2-14 months). Ultrasonography and magnetic resonance imaging were performed for patients with severe symptoms. According to the severity of the symptoms, splint immobilization, oral nonsteroidal anti-inflammatory drugs, and ultrasound-guided steroid injection were performed. Surgical treatment was performed if the patient did not respond to conservative treatment for 3 to 6 months or longer. RESULTS: There were 9 cases of partial rupture of the distal biceps tendon associated with distal biceps tendinopathy on imaging studies. Conservative treatment showed symptomatic improvement in 16 of 21 cases. In 4 cases with a relatively mild symptom, anti-inflammatory analgesics and intermittent splinting showed good result. In 12 cases, symptoms improved after ultrasonography-guided steroid injection. Surgical treatment was performed on 5 cases that did not respond to conservative treatment. CONCLUSIONS: Conservative treatment of distal biceps tendinopathy may promise good results. However, in case of partial tear of the distal biceps tendon and refractory to conservative treatment, surgical treatment may be needed.

Posteromedial Elbow Dislocations without Relevant Osseous Lesions: Clinical Characteristics, Soft-Tissue Injury Patterns, Treatments, and Outcomes.

BACKGROUND: Although simple posterolateral or posterior elbow dislocations are relatively common and usually stable after closed reduction, simple posteromedial dislocations are extremely rare and poorly characterized. We investigated the clinical characteristics, soft-tissue injury patterns, treatments, and outcomes of a series of posteromedial elbow dislocations without relevant osseous lesions. METHODS: We retrospectively reviewed 20 cases of simple posteromedial elbow dislocations without relevant osseous lesions that were treated at 7 fellowship training hospitals during a 10-year period. Soft-tissue injury patterns in 15 cases were investigated with use of magnetic resonance imaging. Clinical outcomes were evaluated after an average of 56.1 months (range, 24 to 93 months) with use of the Mayo Elbow Performance Score (MEPS) and the Quick-DASH (an abbreviated version of the Disabilities of the Arm, Shoulder and Hand [DASH]) score. Complications were also evaluated. RESULTS: On magnetic resonance imaging, significant tears of the lateral collateral ligament complex and common extensor group were observed in all cases. Seventeen cases (85%) required surgical treatment for acute instability. Fourteen cases underwent only lateral complex repair and 3 underwent repair of both the medial and lateral complexes. At the time of the latest follow-up, the mean MEPS and Quick-DASH scores were 85.8 ± 15.0 and 10.5 ± 16.3, respectively. Seventeen patients (85%) had a satisfactory clinical outcome. Complications following treatment included 4 patients with heterotopic ossification; 2 of these patients also experienced posttraumatic elbow stiffness, which was treated with arthrolysis at 8 and 18 months after the initial operation. CONCLUSIONS: Posteromedial elbow dislocations without relevant osseous lesions are associated with a more severe soft-tissue injury, especially to the lateral complex, resulting in a high rate of surgical treatment. With careful post-reduction evaluation, either operative or nonoperative treatment provided satisfactory clinical outcomes. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Endoscopic Olecranon Bursal Resection for Olecranon Bursitis: A Comparative Study for Septic and Aseptic Olecranon Bursitis.

BACKGROUND: Open excision of the olecranon bursa has been performed traditionally. However, surgical complications such as wound healing problems and recurrence may occur after the surgery. The purpose of this study was to report on the clinical outcomes of endoscopic olecranon bursal resection performed in both septic and aseptic olecranon bursitis. METHODS: We retrospectively reviewed 30 patients who underwent endoscopic olecranon bursal resection from June 2007 to January 2012. There were 20 males and 10 females. The ages ranged from 22 to 80 years, with an average age of 57.4 years and the average follow-up was 21.1 months (6-61.5 months). There were 15 cases in the septic group. The treatment outcome was measured according to the following; the rate of recurrence, range of motion, complications associated with surgery, VAS and QuickDASH. RESULTS: There were no complications such as postoperative infection or neurovascular injuries. In the septic group, the VAS and QuickDASH scores were significantly improved from 5.6 to 0.1 and from 28 to 1.3, respectively. In the aseptic group, the VAS and QuickDASH scores were improved from 0.6 to 0.1 and from 25.7 to 0.5, respectively. In all cases, there were no recurrences and no limitations of joint motion until the final follow-up. CONCLUSIONS: We were able to obtain excellent outcomes without recurrence by performing endoscopic olecranon bursal resection in both septic and aseptic olecranon bursitis.

Isolated coronoid fracture: Assessment by magnetic resonance imaging for concomitant injuries.

BACKGROUND: Ligamentous injury associated with isolated coronoid fracture had been sparingly reported. Concealed or unclear fractures and ligamentous or articular cartilage lesions are promptly acknowledged by magnetic resonance imaging (MRI) but cannot be entirely pictured in regular radiological assessments. In isolated coronoid fracture, the fragment size is very small and due to the complex anatomy surrounding the coronoid radiographic imaging may not be sufficient. The purpose of this study was to evaluate the incidence of combined osteochondral and ligamentous injuries by magnetic resonance imaging (MRI) in 24 patients with an isolated coronoid fracture. MATERIALS AND METHODS: In a retrospective study conducted at tertiary hospital between 2009 and 2011, elbow radiographs (anteroposterior and lateral views), computed tomography scan images, and MRI in the sagittal, coronal, axial, oblique, and coronal oblique planes were collected and reviewed. Musculoskeletal radiologist with subspecialty training in musculoskeletal MR interpretation and a fellowship-trained shoulder and elbow surgeon evaluated the MRI. RESULTS: The incidence of associated injuries revealed torn lateral collateral ligament (LCL) in all 24 patients (100%) while 15 patients (62.5%) had common extensor muscle tears. Seven of 24 elbows (29.2%) showed medial collateral ligament (MCL) tear, and 13 of 16 patients (81.3%) with anteromedial facet fracture had MCL attached to the fragment. Five of 24 (20.8%) cases had contusions on the radial head. On the distal humeral side, 15 patients had bone contusions on the posterior inferior of the trochlear on sagittal view. The ligament affections of the LCL were confirmed intraoperatively and repaired. CONCLUSION: LCL injury was consistent in all isolated coronoid fracture. The forces resulting in the injury appear similar to varus distraction forces acting in the knee leading to distraction injuries of the lateral structures of the knee joint. As concurrent osteochondral injuries and ligamentous injuries are not rare, magnetic resonance analysis serves as an excellent tool for analysis of the ligamentous injuries preoperatively and aids in surgical planning.