Anatomic cadaveric study of the extensile extensor digitorum communis splitting approach for exposing the ulnar coronoid process

Treatment of Ulnar Coronoid Process Fracture Using the Anterior Neurovascular Interval Approach: A Retrospective Clinical Study with Short- to Mid-term Follow-up

OBJECTIVE

Numerous surgical techniques for addressing ulnar coronoid process fractures are available; however, a consensus on the optimal approach remains elusive. This study aimed to use the anterior neurovascular interval approach for the surgical management of ulnar coronoid process fractures and to evaluate its clinical outcomes over short- to mid-term follow-up.

METHODS

This retrospective clinical study included 20 patients with ulnar coronoid process fractures who were treated using the anterior neurovascular interval approach between January 2018 and December 2022. Participants comprised 16 males and four females, aged between 20 and 64 years (mean, 34.3 ± 12.44 years). Clinical and radiological evaluations were based on elbow joint range of motion (ROM), Visual analogue scale (VAS), and Mayo elbow performance score (MEPS). A paired t-test was used to compare the pre-operative and final follow-up VAS and MEPS scores.

RESULTS

The follow-up duration for all patients was at least 12 months (average, 12.65 ± 1.60 months). At the final follow-up, measurements of elbow ROM included a mean extension of 2.85 ± 3.17°, mean flexion of 135 ± 7.25°, mean pronation of 86.4 ± 4.56°, and mean supination of 84.85 ± 5.54°. All participants reached their target MEPS, with an average score of 97.25 ± 4.72 points, and the final mean VAS score was 0.2 ± 0.52 points. The VAS score was significantly lower and MEPS score was higher at the final follow-up than those before surgery (p < 0.05). Throughout the follow-up period, all the fractures united, and the stability of the affected elbows was satisfactory.

CONCLUSION

Employing the anterior neurovascular interval approach for open reduction and internal fixation to manage coronoid process fractures effectively facilitates anatomical restoration and robust fixation of ulnar coronoid process fractures.

Location of the posterior interosseous nerve in relation to common lateral approaches to the elbow

PURPOSE

The risk of posterior interosseous nerve (PIN) injury during surgical approaches to the lateral elbow varies depending on the chosen approach, level of dissection, and rotational position of the forearm. Previous studies evaluated the trajectory of the PIN in specific surgical applications to reduce iatrogenic nerve injuries. The goal of this study is to examine the location of the PIN using common lateral approaches with varying forearm rotation.

METHODS

The Kaplan, extensor digitorum communis (EDC) split, and Kocher approaches were performed on 18 cadaveric upper extremity specimens. Measurements were recorded with a digital caliper from the radiocapitellar (RC) joint and the lateral epicondyle to the point where the PIN crosses the approach in full supination, neutral, and full pronation with the elbow at 90°. The ratio of the nerve's location in relation to the entire length of the radius was also evaluated to account for different-sized specimens.

RESULTS

The PIN was not encountered in the Kocher interval. For Kaplan and EDC split, with the forearm in full supination, the mean distance from the lateral epicondyle to the PIN was 52.0 ± 6.1 mm and 59.1 ± 5.5 mm, respectively, and the mean distance from the RC joint to the PIN was 34.7 ± 5.5 mm and 39.3 ± 4.7 mm, respectively; with the forearm in full pronation, the mean distance from the lateral epicondyle to the PIN was 63.3 ± 9.7 mm and 71.4 ± 8.3 mm, respectively, and the mean distance from the RC joint to the PIN was 44.2 ± 7.7 mm and 51.1 ± 8.7 mm, respectively.

CONCLUSIONS

The PIN is closer to the lateral epicondyle and RC joint in the Kaplan than EDC split approach and is not encountered during the Kocher approach. The PIN was not encountered within 26 mm from the RC joint and 39 mm from the lateral epicondyle in any approach and forearm position and is generally safe from iatrogenic injury within these distances.

The spin move to facilitate antegrade coronoid fixation in terrible triad injuries

BACKGROUND

The role of the coronoid process in elbow instability has been established. When necessary, coronoid fixation can be challenging. Placing fixation perpendicular to the fracture requires achieving a trajectory as close as possible to the midline axis of the proximal ulna, either from anterior to posterior or vice versa. The aim of this study was to determine whether coronoid exposure-and the ability to place fixation from anterior to posterior-is improved via a lateral extensor-splitting approach with forearm supination, that is, the "spin move," with progressive stages of lateral elbow instability.

METHODS

The lateral extensor-splitting approach was performed on 9 cadaveric upper extremities. A 0.157-mm (0.062-inch) wire was drilled perpendicularly into the lateral aspect of the humerus just proximal to the lateral epicondyle. A second wire was drilled into the tip of the coronoid, aiming for a drill trajectory as close as possible to the midline axis. The angle between the 2 wires was measured as the initial angle. Three stages of progressive lateral elbow instability were produced by sequential release of the lateral ulnar collateral ligament (LUCL), common extensor origin (CEO), and posterior capsule. At each stage, the spin move was performed and the angle between the 2 wires was measured. The difference between this angle and the initial angle was calculated, with the average value reported as the Δ angle for each stage. The average difference between each stage and the next stage was reported.

RESULTS

The spin move resulted in Δ angles of 10.3° with the LUCL released, 20° with the CEO released, and 29.1° with the posterior capsule released. Progressing from LUCL release to CEO release to posterior capsule release, the Δ angle between the K-wires increased an average of 9.6° from the LUCL stage to the CEO stage and 9.1° from the CEO stage to the posterior capsule stage.

CONCLUSION

The spin move is a simple maneuver that can improve exposure of the coronoid process regardless of the degree of elbow instability. This may facilitate a more perpendicular screw, bone tunnel, or suture anchor trajectory via the lateral approach, reducing the need for posterior-to-anterior fixation. The improved exposure is inferred from the differences in the K-wire angles with and without the spin move. This study has also quantified the change in coronoid exposure using the angles of the wires with progressive release of the LUCL, CEO, and posterior capsule. If necessary, releasing the CEO or posterior capsule with eventual repair may allow improved coronoid fixation from the lateral approach.

Elbow dislocation with lateral condyle and coronoid fractures

Elbow dislocations are simple or complex types. We introduce a patient with the elbow dislocation, lateral condyle fracture and coronoid fracture and their surgical management. This type of fracture is rare in adults. Particular attention should pay to coronoid fracture repair during the treatment.

No neurovascular damage after creation of an accessory anteromedial portal for arthroscopic reduction and fixation of coronoid fractures

PURPOSE

Arthroscopic reduction and internal fixation for coronoid process fractures has been proposed to overcome limitations of open approaches. Currently, arthroscopy is most frequently used to assist insertion of a retrograde guide wire for a retrograde cannulated screw. The present anatomical study presents an innovative arthroscopic technique to introduce an antegrade guide wire from an accessory anteromedial portal and evaluates its safety and reproducibility.

METHODS

Six fresh-frozen cadaver specimens were obtained and prepared to mimic an arthroscopic setting. The coronoid process was localized and a 0.9 mm Kirschner wire was introduced from an accessory anteromedial portal, located 2 cm proximal to the standard anteromedial portal. At the end of the procedure, a lateral radiograph was taken to verify the Kirschner wire position and open dissection was conducted to evaluate possible damage to neurovascular structures.

RESULTS

The Kirschner wire was drilled without complications in the coronoid process of all six specimens. Damage of the brachial artery, the median nerve, and the ulnar nerve did not occur in any specimen. A corridor between the brachialis muscle, the median intermuscular septum, and the pronator teres could be identified as suitable for the wire passage.

CONCLUSION

This study presents a safe and reproducible technique combining the possibility to introduce a guide wire from the anteromedial part of the coronoid, under direct visual control, with a completely arthroscopic approach. This wire can guide the introduction of a retrograde cannulated screw from the dorsolateral ulna to the tip of the coronoid. This new arthroscopic approach permits to obtain improved visual control over coronoid process fixation, without endangering neurovascular structures.

A matched quantitative computed tomography analysis of 3 surgical approaches for osteochondral reconstruction of the capitellum

BACKGROUND

The location of capitellar osteochondritis dissecans (OCD) lesions in the sagittal plane guides the surgical approach used for autologous osteochondral transplantation. We sought to compare the capitellar region accessible for orthogonal graft placement through 3 approaches: (1) posterior anconeus-split approach; (2) lateral approach with lateral collateral ligament (LCL) preservation (LCL-preserving lateral approach); and (3) lateral approach with LCL release (LCL-sacrificing lateral approach).

METHODS

The 3 approaches were sequentially performed on 9 cadaveric elbows: posterior anconeus-split approach, LCL-preserving lateral approach, and LCL-releasing lateral approach. The extent of perpendicular access was delineated with Kirschner wires. Each specimen underwent computed tomography. The accessible region was quantified as degrees on the capitellum and converted into time on a clock, where 0° corresponds to the 12-o'clock position. Generalized estimating equation modeling was used to investigate for significant within-specimen, between-approach differences.

RESULTS

The LCL-preserving and LCL-sacrificing lateral approaches provided more anterior perpendicular access than the posterior anconeus-split approach (mean, 0° vs 83°; P < .001). The posterior anconeus-split approach provided more posterior perpendicular access (mean, 215.0°; P < .001) than the LCL-preserving (mean, 117°; P < .001) and LCL-sacrificing (mean, 145°; P < .001) lateral approaches. The LCL-sacrificing lateral approach provided more posterior exposure than the LCL-preserving lateral approach (mean, 145° vs 117°; P < .001). The mean arc of visualization was greater for the LCL-sacrificing lateral approach than for the LCL-preserving lateral approach (145° vs 117°, P < .001).

CONCLUSIONS

A capitellar OCD lesion can be perpendicularly accessed from a posterior anconeus-split approach if it is posterior to 83° (2:46 clock-face position). A laterally based approach may be required for lesions anterior to this threshold. These data inform clinical decisions regarding the appropriate surgical approach for any OCD lesion.

[Effectiveness of improved elbow anteromedial approach in treatment of ulna coronoid process fracture]

Objective

To observe the effectiveness of reduction and fixation by the improved elbow anteromedial approach in treatment of ulna coronoid process fracture.

Methods

Between January 2010 and December 2014, 13 patients with the ulna coronoid process fracture were treated with reduction and fixation by the improved elbow anteromedial approach. There were 10 males and 3 females with an average age of 37.2 years (range, 18-57 years). Five cases were caused by traffic accident, 7 cases by falling injury from height, and 1 case by object impact injury. Seven cases were the terrible triad of the elbow, 4 cases were the ulna coronoid process and radial head fractures, 1 case was the proximal radius and ulna fractures, and 1 case was the ulna coronoid process and distal radius fractures. According to Regan-Morrey classification criteria, the ulna coronoid process fracture was rated as type Ⅱ in 2 cases and as type Ⅲ in 11 cases. According to O'Driscoll classification criteria, 10 of the 13 cases were anterior coronoid fracture (8 cases of type Ⅱb, 2 of type Ⅱc), and 3 of basal fracture. The operation time, amount of intraoperative bleeding, postoperative complications, range of motion (ROM) of the elbow joint, Mayo elbow function index (MEPI) score and fracture healing time were recorded.

Results

The average operation time was 38.7 minutes (range, 30-55 minutes), and the average amount of intraoperative bleeding was 109.3 mL (range, 90-160 mL). All incisions healed at stage Ⅰ. There was no iatrogenic vascular or nerve injury. All patients were followed up 13-24 months (mean, 16.9 months). All fractures achieved clinical healing. The average healing time was 11.2 weeks (range, 8-16 weeks). There were 2 cases of heterotopic ossification. At last follow-up, the ROM of elbow flexion was 119-145° (mean, 132.4°); the ROM of elbow extension was -8-15° (mean, 7°). The ROM of forearm pronation was 68-90° (mean, 78.6°), and the ROM of forearm supination was 76-90° (mean, 84.3°). At last follow-up, the MEPI score was 70-100; and 9 cases were excellent, 3 cases were good, and 1 case was fair. The excellent and good rate was 92.3%.

Conclusion

Improved elbow anteromedial approach for the ulna coronoid process fracture can not only avoid the injuries of surrounding blood vessels and nerves, but also perform fracture reduction and fixation under direct vision. It is a safe, simple, and effective treatment method for the ulna coronoid process fracture.

Avoiding radial nerve palsy in proximal radius shaft plating - a cadaver study

BACKGROUND

Opinions vary concerning the position of forearm rotation during detachment of the supinator in radial nerve palsy Henry's and Thompson's approaches.

PURPOSE

To define the optimal forearm position for a safe detachment of the supinator during these approaches and to clarify their close relationship to the posterior interosseous nerve (PIN).

METHODS

The study sample comprised 90 upper extremities of 45 human adult cadavers, embalmed using Thiel's method. After detection of the radial nerve in the interval between the brachialis and brachioradialis, its pathway was traced to the Arcade of Frohse (AF). Measurements involved the distance between the AFand the radial border of the distal biceps tendon (DBT) in pronation and supination, the interval between the AF and the radiocapitellar joint space (RCJS) in supination and the radial length (RL).

RESULTS

Distances between the DBT and the AF were significantly shorter during pronation (right side: 14.1 ± 3.4mm; left side: 13.5 ± 3.2mm) compared with supination (right side: 20.5 ± 3.6mm; left side: 19.8 ± 3.5mm) for both right and left extremities. The mean interval between the AF and the centre of the RCJS was 25.2 ± 5.9mm for the right side and 24.7 ± 5.6mm for the left side, which correlated positively with the RL.

CONCLUSION

These results indicate a safe detachment of the supinator from the radius with the forearm placed in supination during both Henry's and Thompson's approaches.

Arthroscopic reduction and fixation of coronoid fractures with an exchange rod-a new technique

BACKGROUND

The ulnar coronoid process plays a central role in maintaining elbow stability. Some of its fractures were often combined with injury of bone and ligament. Arthroscopy enables perfect visualization to allow anatomical repair.

METHODS

From January 2012 to December 2013, six patients (four males, two females) with a mean age of 26.6 years were treated. The left and right ulnas were involved in two and four patients, respectively. All patients suffered from ipsilateral subluxation of the elbow without associated radial fracture. According to the Regan and Morrey fracture classification and O'Driscoll's classification, two and four patients were classified as type I and type II and as having tip fracture (O'Driscoll type I) and anteromedial fracture (O'Driscoll type II), respectively. Exchange rod technology via the elbow front center approach was used for reduction and fixation of fractures of the coronoid process of the ulna.

RESULTS

Intra- and postoperative X-ray examination showed that the fractures were satisfactorily fixed and that the screw and fracture line were vertical to each other. Follow-ups showed that the fractures had healed well, and the average elbow extension was -2° while the average flexion was 140°. No problems related to pronation or supination, elbow instability, or complications of blood vessels or nerves were reported. The elbows showed excellent results according to the Mayo Elbow Performance Score.

CONCLUSIONS

Arthroscopy using an exchange rod can provide excellent visual exposure of the fractured joints, without the need for a large incision during the anatomical repair. Moreover, it protects the surrounding soft tissue, shows good stability of the components, and allows early rehabilitation exercises.