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.

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.

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.

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.