Anteromedial fracture of the coronoid process of the ulna

Morphological Characteristics of Proximal Ulna Fractures: A Proposal for a New Classification and Agreement for Validation

Historically, proximal ulna fractures have been simplistically diagnosed and treated as simple olecranon fractures, leading to an unacceptable number of complications. Our hypothesis was that the recognition of lateral, intermediate, and medial stabilizers of the proximal ulna and ulnohumeral and proximal radioulnar joints would facilitate decision-making, including the choice of approach and type of fixation. The primary aim was to propose a new classification for complex fractures of the proximal ulna based on morphological characteristics seen on three-dimensional computed tomography (3D CT). The secondary aim was to validate the proposed classification regarding its intra- and inter-rater agreement. Three raters with different levels of experience analyzed 39 cases of complex fractures of the proximal ulna using radiographs and 3D CT scans. We presented the proposed classification (divided into four types with subtypes) to the raters. In this classification, the medial column of the ulna involves the sublime tubercle and is where the anterior medial collateral ligament is inserted, the lateral column contains the supinator crest and is where the lateral ulnar collateral ligament is inserted, and the intermediate column involves the coronoid process of the ulna, olecranon, and anterior capsule of the elbow. Intra- and inter-rater agreement was analyzed for two different rounds, and the results were evaluated according to Fleiss kappa, Cohen kappa, and Kendall coefficient. Intra- and inter-rater agreement values were very good (0.82 and 0.77, respectively). Good intra- and inter-rater agreement attested to the stability of the proposed classification among the raters, regardless of the level of experience of each one. The new classification proved to be easy to understand and had very good intra- and inter-rater agreement, regardless of the level of experience of each rater.

Comparison of arthroscopy-assisted vs. open reduction and fixation of coronoid fractures of the ulna

PURPOSE

The purpose of this study was to compare clinical and radiographic outcomes and complications for arthroscopy-assisted vs. open reduction and fixation of coronoid fractures in patients with complex elbow fracture-dislocations.

METHODS

This retrospective study analyzed patients with complex elbow fracture-dislocations who underwent surgical fixation for coronoid fractures of the ulna from March 2009 to January 2016. Subjects included those who received either arthroscopy-assisted (group A) or open surgery (group O) for coronoid fractures and concurrent reconstruction of the lateral column (radial head and/or lateral ulnar collateral ligament) with follow-up for at least 2 years. Clinical outcomes were assessed using the visual analog scale for pain, range of motion, Mayo Elbow Performance Score, and Disabilities of the Arm, Shoulder, and Hand score at 2 years after surgery. For radiographic assessment, union of the coronoid, development of heterotopic ossification, and arthritic changes were evaluated. We also reviewed surgery-related complications.

RESULTS

Twenty-five patients (mean age, 40.0 ± 12.4 years) were enrolled in this study (group A, 15 patients; group O, 10 patients), and there were no statistical differences in baseline data between the 2 groups. Clinical outcomes did not differ between the 2 groups. All fractures were united and that the prevalence of heterotopic ossification and arthritic changes were similar between the 2 groups. However, operation-related complications were more common in group O than in group A (group A, 13.3%; group O, 40.0%), including 1 patient who underwent ulnar nerve neurolysis and anterior transposition at 3 months after the initial operation.

CONCLUSIONS

Eliciting fewer complications, arthroscopy-assisted reduction and fixation of coronoid fractures shows union rates and clinical results comparable to open fixation in patients with complex elbow fracture-dislocation.

Buttress plate fixation of coronoid process fractures via a medial approach

PURPOSE

To assess the clinical and radiographic outcomes of coronoid process fractures surgically managed with buttress plate fixation via a medial approach.

METHODS

A retrospective review of all coronoid fractures surgically fixed in our institution using a buttress plate technique via a medial approach between June 2012 and April 2015 by the senior author was performed. These fractures were all sizeable fractures contributing to persistent elbow instability in terrible triad or varus posteromedial rotatory instability injury patterns. A prospective telephone questionnaire was conducted to assess patient outcomes using the disabilities of the arm, shoulder and hand (DASH) score and Mayo hlbow performance score (MEPS).

RESULTS

Twelve patients were included in the study, comprising 10 males and 2 females with an average age of 39 years (range, 19-72 years). Mean follow-up was 16 months (range, 4-18 months). The average time to radiographic union was 4 months (range, 3-7 months). Range of motion measurements at final follow-up were obtained in 11 out of 12 patients, with one patient defaulting follow-up. All 11 patients displayed a functional elbow range of motion of at least 30°-130°, with an average arc of motion of 130° (range, 110° -140°), mean elbow flexion of 134° (range, 110° -140°) and mean flexion contracture of 3° (range, 0° -20°). The mean DASH score was 16 (range, 2.5-43.8) and the mean MEPS was 75 (range, 65-100). Complications observed included one patient with a superficial wound infection which resolved with a course of oral antibiotics and one patient with radiographic evidence of heterotopic ossification which was conservatively managed. No residual elbow instability was observed and no reoperations were performed.

CONCLUSION

Buttress plate fixation via a medial approach of coronoid process fractures that contribute to persistent elbow instability represents a reliable method of treatment that produces satisfactory and predictable outcomes.

Arthroscopically-assisted fixation of anteromedial coronoid facet fracture and lateral ulnar collateral ligament repair for acute posteromedial rotatory fracture dislocation of the elbow

If left untreated, varus posteromedial rotatory injuries of the elbow result in poor functional outcomes. Surgical treatment allows restoration of elbow kinematics, minimizing the chances of chronic varus instability and early onset osteoarthritis. However, large exposures are associated with extensive soft tissue stripping, a high risk of infection, nerve injury, poor visualization of the articular surface and longer recovery. Consequently, there has been renewed interest in the use of elbow arthroscopy to circumvent these problems. Arthroscopic treatment offers the potential advantage of a swift recovery, with instant rehabilitation, less stiffness and swelling than might be expected after open repair. We present the first combined arthroscopic-assisted anteromedial facet coronoid fracture fixation and lateral ulna collateral ligament repair in a varus posteromedial rotatory injury of the elbow.

Most coronoid fractures and fracture-dislocations with no radial head involvement can be treated nonsurgically with elbow immobilization

HYPOTHESIS

Conservative treatment of isolated coronoid fractures and fracture-dislocations focused on soft-tissue healing can provide good clinical results in the majority of patients. Our aims were (1) to evaluate the outcome of a conservative treatment protocol designed for isolated coronoid fractures with or without associated elbow dislocations (ICFs) and (2) to characterize the fractures with a dedicated image analysis protocol.

METHODS

Of 38 consecutive patients sustaining acute ICFs, 28 were treated nonsurgically after meeting specific inclusion criteria, prospectively followed up, and clinically evaluated at least 1 year after sustaining their injuries. All cases underwent elbow computed tomography scans with tri-plane and 3-dimensional reconstructions according to a specific protocol referenced to the proximal ulna.

RESULTS

The study included 15 male and 13 female patients, with a mean follow-up period of 32 ± 14 months (range, 12-61 months). An associated dislocation was presented in 8 (29%). Mean extension and flexion were 2° ± 8° (range, -10° to 30°) and 139° ± 11° (range, 110°-155°), respectively. Mean pronation and supination were 74° ± 3° (range, 60°-75°) and 83° ± 9° (range, 40°-85°), respectively. Of the patients, 78% rated their elbow as being normal or nearly normal. The mean Mayo Elbow Performance Score was 95 ± 9 (range, 70-100). The mean Disabilities of the Arm, Shoulder and Hand score was 7 ± 13 (range, 0-57). The mean coronoid fracture height was 5.7 ± 1.2 mm (range, 3.7-7.9 mm). The mean percentage of coronoid height fractured was 33% ± 6% (range, 23%-43%). Mean fracture displacement was 2.7 ± 2 mm (range, 1-9 mm). Of the fractures, 23 (82%) were located at the anteromedial coronoid.

CONCLUSION

An ICF with a perfectly reduced ulnohumeral joint, a competent sublime tubercle, and a fractured coronoid height up to 50% can be treated without surgery with excellent or good results in more than 90% of cases regardless of the location of the fracture in the coronoid or the type of soft tissue-associated disruptions.

Posteromedial rotatory incongruity of the elbow: a computational kinematics study

BACKGROUND

Our objective was to analyze the effect of different anteromedial coronoid fracture patterns with different combinations of ligamentous repairs. We hypothesized that smaller fractures would be sufficiently treated with ligamentous repair alone but that larger fragments would require a combination of ligament and bony repair versus reconstruction.

METHODS

Two multibody models were created from cadaveric specimens in the ADAMS program. Four different conditions were simulated: (1) no fracture, (2) O'Driscoll anteromedial subtype I (2.5-mm) fracture, (3) subtype II 2.5-mm fracture, and (4) subtype II 5-mm fracture. In each of these conditions, 3 ligament repairs were studied: lateral ulnar collateral ligament (LUCL), posterior bundle of the medial collateral ligament (pMCL), and both LUCL and pMCL. For each condition, kinematics and articular contact areas were calculated.

RESULTS

LUCL repair alone increases whereas pMCL repair decreases internal rotation of the ulna relative to all tested posteromedial rotatory instability conditions; their rotational effects are summative when both ligaments are repaired. With a subtype I fracture and both pMCL and LUCL injuries, repairing the LUCL alone corrects angulation whereas rotational stability is satisfactory through the arc from 0° to 90°. In a subtype II 2.5-mm fracture, isolated repair of the LUCL or pMCL is not capable of restoring rotation or angulation. For a subtype II 5-mm fracture, no combination of ligamentous repairs could restore rotation or angulation.

CONCLUSIONS

This study suggests that LUCL repair alone is sufficient to restore kinematics for small subtype I fractures for an arc avoiding deep flexion; whereas nearly normal kinematics throughout the arc of motion can be achieved if the pMCL is also repaired. Larger anteromedial coronoid fractures should ideally have fragments fixed in addition to ligament repairs.

[Research progress of posteromedial rotatory instability of the elbow]

Objective

To summarize the research progress in posteromedial rotatory instability (PMRI) of the elbow joint.

Methods

The recent researches about the management of PMRI of the elbow joint from the aspects of pathological anatomy, biomechanics, diagnosis, and therapy were analyzed and summarized.

Results

The most important factors related to PMRI of the elbow joint are lateral collateral ligament complex (LCLC) lesion, posterior bundle of the medial collateral ligament complex (MCLC) lesion, and anteromedial coronoid fracture. Clinical physical examination include varus and valgus stress test of the elbow joint. X-ray examination, computed tomography, particularly three-dimensional reconstruction, are particularly useful to diagnose the fracture. Also MRI, arthroscopy, and dynamic ultrasound can assistantly evaluate the affiliated injury of the parenchyma. It is important to repair and reconstruct LCLC and MCLC and fix coronoid process fracture for recovering stability of the elbow joint. There are such ways to repair ligament injury as in situ repairation and functional reconstruction, which include direct suturation, borehole repairation, wire anchor repairation, and transplantation repairation etc. The methods for fixation of coronal fracture include screw fixation, plate fixation, unabsorbable suture fixation, and arthroscopy technology.

Conclusion

It is crucial that recovering the stability of the elbow joint and early functional exercise for the treatment of PMRI. Individual treatment is favorable to protect soft tissue, reduce surgical complications, and improve the functional recovery and the quality of life.

Arthroscopic fixation of coronoid process fractures through coronoid tunnelling and capsular plication

PURPOSE

the purpose of this study is to describe a new arthroscopic technique for reduction and fixation of coronoid process fractures (CPFs) and report clinical and functional results in 4 patients after a 24-month follow-up.

METHODS

four patients underwent arthroscopic reduction and fixation of isolated CPFs (acute or non-unions, type I or type II according to the Regan-Morrey classification) performed using a new technique based on coronoid tunnelling and capsular plication. The patients were evaluated 6, 12 and 24 months after surgery, using the Disability of the Arm, Shoulder and Hand scale (DASH), the Mayo Elbow Performance Index (MEPI), and a visual analog scale (VAS); elbow range of motion (ROM) and joint stability were also evaluated and the rate of complications was reported.

RESULTS

all 4 patients completed the follow-up. At 6, 12 and 24 months, respectively, they recorded mean DASH scores of 22, 14 and 7, mean MEPI scores of 74, 82 and 94, and mean VAS scores of 4, 2 and 1. The mean ROM increased in all directions (at 6, 12 and 24 months, respectively: flexion: 112°, 125°, 144°; extension: 3°, 5°, 6°; pronation: 76°, 84°, 91°; supination: 78°, 82°, 86°). No signs of instability were observed and no complications were reported.

CONCLUSIONS

the new all-arthroscopic coronoid tunnelling and capsular plication technique here proposed can restore elbow function, ROM and stability and allows anatomical reconstruction of the joint after type I or type II CPFs. If performed by an experienced arthroscopist, it is a valid alternative to open reduction and external fixation.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Complex coronoid and proximal ulna fractures are we getting better at fixing these?

Technological advances and improved understanding of functional anatomy about the elbow have lead an evolution regarding operative reconstruction of complex proximal ulnar and coronoid fractures. When treating these complex and challenging fractures, goals of anatomic articular restoration along with balanced soft tissue stability can lead to early range of motion and thus, desired functional outcome. The purpose of this review is to outline and provide tips and pearls to achieve desired results, with a comprehensive update on the most recent literature to support the latest fixation methods and techniques.

Stress Fracture and Nonunion of Coronoid Process in a Gymnast

Background. Gymnasts have high mechanical loading forces of up to 14 times body weight. Overuse lesions are typical in wrists and stress fractures in the olecranon, while isolated fractures of the coronoid process are uncommon. We present a case of retraumatized nonunion stress fracture of the ulnar coronoid process. Case Description. A 19-year-old gymnast presented with elbow pain after training. Imaging confirmed an old fracture of the coronoid process. We describe a 6-month multiphase return to competition rehabilitation program, which allowed him to compete pain-freely. Literature Review. Acute and overuse injuries in gymnasts are known but no nonunion of the coronoid process has been described before. Only one case of stress fracture of coronoid process in a gymnast was reported. Purpose and Clinical Relevance. We could successfully and conservatively return to sport a reactivated nonunion of a stress fracture of the coronoid process.

How should anteromedial coronoid facet fracture be managed? A surgical strategy based on O'Driscoll classification and ligament injury

BACKGROUND

Despite an improved understanding of coronoid anteromedial facet (AMF) fractures, the optimal treatment protocol and technique have not yet been established. The goals of the study were to describe the characteristics of AMF fractures, to suggest a surgical strategy, and to report the outcomes after treatment according to this protocol.

METHODS

This was a retrospective study of 19 patients with AMF fractures between 2010 and 2012. Eight patients were excluded because of secondary olecranon fracture, radial head fracture, and elbow dislocation, leaving 11 patients with isolated AMF fracture in the study cohort. There were 7 men and 4 women, with an average age of 42 years (range, 29-62 years). Fracture classification, injury pattern, and accompanying collateral ligament injury were analyzed. O'Driscoll subtype 1 fractures were treated with lateral collateral ligament (LCL) repair; O'Driscoll subtype 2 and subtype 3 fractures were treated with buttress plating and LCL repair. Plain radiographs were used to evaluate union, arthritic change, and joint articulation. Functional outcomes were evaluated with range of motion and the Mayo Elbow Performance Score.

RESULTS

Two patients had O'Driscoll anteromedial subtype 1 fracture, 4 patients had subtype 2, and 5 patients had subtype 3. Two patients with subtype 1 fracture had associated posterior dislocation; 9 patients with subtype 2 or subtype 3 had associated varus posteromedial injury. All 11 patients had associated LCL injury, and 6 patients had associated medial collateral ligament injury. The mean range of motion was 128°, and the average Mayo Elbow Performance Score was 89 points. Qualitatively, patient outcomes were scored excellent in 4 patients, good in 6 patients, and fair in 1 patient.

CONCLUSION

AMF fractures are almost always accompanied by collateral ligament injuries. Thus, our surgical strategies, which include collateral ligament repair, are able to stabilize and result in favorable clinical outcomes. On the basis of our results, we recommend LCL repair alone for subtype 1 fractures and buttress plating and LCL repair for subtype 2 and subtype 3 fractures.

Management of complex elbow instability

Complex elbow instability is a challenging injury even for expert elbow surgeons. The preoperative radiographs should be carefully evaluated to recognize all lesions that may occur in complex elbow instabilities. Recognizing all the possible lesions is critical to achieve an optimal outcome. The most common types of injuries are as follows: (1) radial head fractures associated with lateral and medial collateral ligaments lesions (with or without elbow dislocation); (2) Coronoid fractures and lateral collateral ligament lesion (with or without elbow dislocation); (3) Terrible Triad; (4) Transolecranon fracture-dislocation; (5) Monteggia-like-lesions; and (6) Humeral Shear fractures associated with lateral and medial collateral ligaments lesions (with or without elbow dislocation). A correct evaluation includes X-rays, CT scan with 2D and 3D reconstruction and stability test under fluoroscopy. The treatment is always surgical and is challenging, and outcomes are not predictable. The goals of treatment are (1) to perform a stable osteosynthesis of all fractures, (2) to obtain concentric and stable reduction of the elbow and (3) to allow early motion. The proximal ulna must be anatomically reduced and fixed; the radial head must be repaired or replaced, and the coronoid fractures must be repaired or reconstructed. With respect of soft tissue lesions, the LUCL must be reattached with suture anchors or trans-osseous suture. The next critical step is the intra-operative assessment of elbow stability. If the elbow remains unstable, MCL repair and/or application of hinged external fixator must be considered. The most recent clinical and experimental studies have significantly expanded our knowledge of elbow instability and its management. Definite treatment protocols may improve the clinical results of such complex injuries.

Surgical approaches to the elbow

Surgical exposures for complex injuries about the elbow are technically demanding because of the high density of neurologic, vascular, and ligamentous elements around the elbow. The posterior approaches (ie, olecranon osteotomy, triceps-reflecting, triceps-splitting, triceps-reflecting anconeus pedicle flap, paratricipital) include techniques used to navigate the area around the triceps tendon and anconeus muscle. These approaches may be extended to gain access to the entire joint. The ulnar nerve, the anterior and posterior capsules, and the coronoid process are addressed by means of a medial approach. Lateral approaches are useful in addressing pathology at the radial head, capitellum, coronoid process, and anterior and posterior capsules. These approaches may be combined to address complex pathology in the setting of fracture fixation, arthroplasty, and capsular release.

Effect of the posterior bundle of the medial collateral ligament on elbow stability

PURPOSE

The role of the posterior bundle of the medial collateral ligament in stability of the elbow remains poorly defined. The purpose of this study was to determine the effect of sectioning the posterior bundle of the medial collateral ligament on the stability of the elbow.

METHODS

Varus and valgus gravity-loaded passive motion and simulated active vertical motion were performed on 11 cadaveric arms using an in vitro elbow motion simulator. Varus/valgus angle and internal/external rotation of the ulna with respect to the humerus were recorded using an electromagnetic tracking system in varus, valgus, and vertical orientations. Testing was performed on the intact elbow and after sectioning of the posterior bundle of the medial collateral ligament.

RESULTS

With active flexion in the vertical position, the varus/valgus kinematics were unchanged after sectioning of the posterior bundle of the medial collateral ligament. However, in pronation, there was an increase in internal rotation after sectioning of the posterior bundle of the medial collateral ligament compared with that of the intact elbow. This rotational difference was not detected with the forearm in supination. During supinated passive flexion in the varus position, sectioning of the posterior bundle of the medial collateral ligament resulted in increased varus angulation at all flexion angles. In pronation, varus angulation and internal rotation both increased. In supination, sectioning of the posterior bundle of the medial collateral ligament had no effect on maximum varus-valgus laxity or maximum internal rotation. However, in pronation, the maximum varus-valgus laxity increased by 3.5 degrees (30%) and maximum internal rotation increased by 1.0 degrees (29%).

CONCLUSIONS

These results indicate that isolated sectioning of the posterior bundle of the medial collateral ligament causes a small increase in varus angulation and internal rotation during both passive varus and active vertical flexion. This study suggests that isolated sectioning of the posterior bundle of the medial collateral ligament may not be completely benign and may contribute to varus and rotation instability of the elbow. In patients with insufficiency of the posterior bundle of the medial collateral ligament, appropriate rehabilitation protocols (avoiding forearm pronation and shoulder abduction) should be followed when other injuries permit.

Coronoid fractures of the elbow

Coronoid fractures of the ulna are relatively uncommon, yet critical injuries to recognize. They often occur in association with elbow dislocations and play an important role in elbow instability. Historic recommendations are to fix all large coronoid fracture fragments, as well as small fracture fragments associated with instability. There is little data regarding management of small coronoid fracture fragments. The coronoid process acts as a bony buttress to prevent posterior dislocation and has three soft tissue insertions which lend stability as well: the anterior joint capsule of the elbow, the brachialis muscle and the medial ulnar collateral ligament. Injured patients often present with swelling, tenderness and limited range of motion. After obtaining a detailed history and performing a careful physical examination, plain radiographs should be obtained. If present, dislocations are reduced and post-reduction stability is assessed. If the elbow is unstable, management usually consists of a combination of bony and soft-tissue repairs often including coronoid process repair. Loss of motion is the most common complication of these injuries. The current recommendation is to repair virtually all coronoid fractures associated with instability.