Internal joint stabilizer for varus posteromedial rotatory instability of the elbow

A single-surgeon experience with the internal joint stabilizer of the elbow across 56 cases

Background

Recurrent instability continues to plague outcomes of elbow trauma. Adjuvant stabilization-whether internal or external-is intended to acutely stabilize the elbow and off-load the repair construct(s) during early mobilization. Our objective was to report clinical outcomes for a single-surgeon consecutive series using the internal joint stabilizer (IJS) of the elbow. Furthermore, we intend to describe technical points that have been gleaned from the experience which may provide guidance.

Methods

A retrospective follow-up was performed for cases of elbow instability treated with the IJS (Skeletal Dynamics, Miami, Florida, USA) from 2016-2023 with a minimum requirement of 6 months of follow-up. Clinical outcomes and complications including recurrent instability were compiled.

Results

Of 87 potential cases, 56 met the inclusion criteria. Simple dislocations (30%) and terrible triad injury (21%) were the most common injury patterns. The mean Mayo Elbow Performance Score was 81 and the mean Disabilities of the Arm, Shoulder, and Hand score was 22.5. Recurrent instability occurred in 5.3% of cases. The mean time to removal was 21.1 weeks.

Discussion

Our utilization of the IJS of the elbow has evolved from simple dislocations to complex instability cases. Results demonstrated satisfactory clinical outcomes with low rates of recurrent instability and revision. The ability for early mobilization was a critical determinant for using an IJS in these cases. This advantage carried particular importance in cases that presented subacutely following an extended course of immobilization. Our protocol for removal timing is applied on a case-by-case basis and involves identification of sufficient rehabilitation and clinical stability.

Internal brace augmentation in elbow varus posteromedial rotatory instability (VPMRI) allows early rehabilitation and prevents stiffness

PURPOSE

Varus posteromedial rotatory instability (VPMRI) involves anteromedial coronoid fracture (AMCF), lateral ulnar collateral ligament (LUCL), and medial collateral ligament (MCL) injury. There is no general consensus regarding the surgical treatment, but most surgeons recommend internal fixation of the coronoid along with primary ligament repair. This methodology involves postoperative immobilization to allow ligament healing, occasionally associated with stiffness. Augmentation of one/or both collateral ligaments using a non-absorbable suture tape as an internal brace in VPMRI cases was the subject of the presented study. This method allows brace-free initiation of full elbow range of motion while protecting bony and soft tissue healing.

METHODS

17 patients (13 males and four females) with VPMRI were treated in the center from 2017 to 2021 with internal brace augmentation of collateral ligament along with ORIF (Open reduction & internal fixation)/ reconstruction of the coronoid fragment. All patients were actively mobilized early after surgery. Patients who completed a minimum follow up of 24 months were included in the study. Clinical examination findings at follow-up assessment included ROM (range of motion) recording and instability testing, including special instability tests such as moving valgus stress test, lateral pivot shift test, Posterolateral rotatory drawer test, and gravity-assisted varus stress test. Disabilities of arm, shoulder and hand (DASH) score, Mayo Elbow Performance Score (MEPS), Oxford Elbow Score (OES), Visual Analogue Score (VAS), and SEV (Simple Elbow values) were assessed and noted at follow-up.

RESULTS

At 43 months of mean follow-up, none of the patients had significant postoperative contracture, and none had any clinically apparent signs of instability or suffered subluxation or re-dislocation. Postoperative radiographs showed complete fracture/graft healing with no signs of subluxation in all patients. The mean range of motion of the patients was 6.20 (1.00-11.30) to 139.10 (136.20-142.00), with a mean Oxford elbow score (OES) of 42.0 (39.9-44.7). The mean DASH (Disability of Arm, Shoulder & Hand) score was 11.4 (6.7-16.1), the mean MEPS (Mayo Elbow Performance Score) was 91.2 (86.3-96.0), the mean Visual Analogue Score (VAS) score was 0.6 (0.1-1.2), and the mean Simple Elbow value (SEV) was 85.4% (81.1-89.8%).

CONCLUSION

Internal brace augmentation with a non-absorbable suture tape in the setting of VPMRI is a safe and helpful adjunct to coronoid repair/reconstruction and primary ligament repair and allows early mobilization and recovery of elbow stability and range of motion.

Residual Elbow Instability Treated with a Submuscular Internal Joint Stabilizer: Prospective and Consecutive Series with a Minimum Follow-Up of 12 Months

Background: The management of residual elbow instability is a challenging and compelling issue for treating physicians. To overcome inherent drawbacks of dynamic external fixators, the internal joint stabilizer (IJS) has been developed, achieving successful results, but it can sometimes cause local tenderness or anesthetic concerns in the subcutaneous layer. In addition, a bulky anconeus can pull the hardware away from the axis of rotation with an increase in the lever arm and potential issues. To address these issues, an alternative approach has been recently described in which the internal device is covered by the anconeus muscle, becoming submuscular, rather than subcutaneous. The aim of this study was to evaluate the effectiveness of this alternative approach to the IJS application in maintaining a concentric elbow during and after device removal in both acute and chronic scenarios. Methods: Prospective data collection was performed with consecutive patients who had residual elbow instability treated with an IJS (Skeletal Dynamics, Miami, FL) covered by the anconeus from January 2022 and with a minimum follow-up of 12 months. Results: At a medium follow-up of 16 months, the 16 patients selected had a mean arc of flexion-extension of 123° (range: 0-140°) and a mean pronation-supination arc of 150° (range: 80-80°). The mean MEPS and DASH scores were 90.3 ± 6.2 and 6.3 ± 5.3, respectively. At the last follow-up, elbow stability and concentric reduction were confirmed with radiographic and clinical examinations. Conclusions: With a minimum follow-up of 12 months, the present study supports the safety and efficacy of the internal device in a submuscular layer. The clinical outcomes and the rate of recurrent instability are comparable to those achieved with a classic subcutaneous position. Similarly, the complication rate is not affected, and removal surgery is no more aggressive than the classic approach.

The internal joint stabilizer for elbow instability: current concepts

The management of residual elbow instability is challenging in both acute and chronic injuries. Among the available devices, the hinged external fixator provides an additional joint stabilization while allowing an early motion, but it is clumsy and associated to high rate of pin track complications. To address these issues, an internal joint stabilizer (IJS) has been recently developed. An easier recreation of the axis of rotation coupled to the reduced lever arm of the hinge is the root of the consistent and satisfactory results thus far observed. In addition, the device is more comfortable for the patients being an internal stabilizer. Nonetheless, a second surgery for the device removal is necessary, of which the timing is still not standardized. This current concepts paper describes literature regarding outcomes of the IJS focusing on the rate of maintained radiographic joint reduction, the resultant range of motion, and the associated complication profile.

The Internal Joint Stabilizer of the Elbow: A Systematic Review of the Clinical and Biomechanical Evidence

Purpose

The goal of surgical management for unstable elbow injuries is the restoration of joint concentricity and stability. After internal fixation, concerns may exist regarding instability or durability of the fixation construct. Historically, these scenarios were treated with options such as transarticular pinning or external fixation. Recently, an internal joint stabilizer (IJS) that allows postoperative mobilization was introduced. Our objective was to systematically review the literature to aggregate the clinical and biomechanical evidence for the IJS of the elbow.

Methods

A systematic review of the PubMed and Google Scholar databases was performed, following the PRISMA guidelines. The search results were narrowed from 2015 through 2023 to coincide with the inception of the device being reviewed.

Results

A total of nine retrospective reports on the IJS (N = 171) cases at a mean follow-up of 10.8 months were included. The pooled rate of implant failure was 4.4%, and recurrent instability was 4.1%. Additionally, the we included seven case reports and two biomechanical reports.

Conclusions

The aggregate literature describes satisfactory clinical outcomes with low rates of recurrent instability and device failure for the IJS of the elbow. The limited biomechanical investigations conclude efficacy for stability profiles.

Clinical relevance

Across a spectrum of unstable elbow cases, the IJS prevented recurrent instability during the early postoperative period. Notably, the device requires an additional procedure for removal, and the long-term impact of the retained devices is currently unclear.

Using External Joint Stabilizer - Elbow (EJS-E) for treating elbow instability-biomechanical assessment and clinical outcomes

BACKGROUND

This study aimed to evaluate the outcome of using an External Joint Stabilizer - Elbow (EJS-E) for persistent elbow instability based on biomechanical experiments and analysis of clinical results.

METHODS

An EJS-E was used in 17 elbow instability patients. The median follow-up was 26 months (range, 12-42 months). We evaluated the flexion-extension and pronation-supination movement arcs, visual analog scale (VAS) score, Mayo Elbow Performance Score (MEPS), Broberg and Morrey classification system, and occurrence of complications in these patients. Moreover, construct stiffness and maximum strength tests were performed to evaluate the strength of the fixation techniques.

RESULTS

The final median range of the extension-to-flexion and pronation-to-supination arc of the elbow was 135° (range, 110°-150°) and 165° (range, 125°-180°), respectively. The VAS pain scores were > 3 in two patients. The median MEPS was 90 (range, 80-100 points). Five patients showed signs of grade I post-traumatic osteoarthritis according to the Broberg and Morrey radiographic classification system, while grade II changes were observed in three patients. Complications included axis pin loosening with pin-tract infection in two patients, transient ulnar nerve symptoms in two patients, heterotopic ossification in two patients, and suture anchors infection in one patient. Based on the biomechanical testing results, the EJS-E exhibited higher stiffness and resisting force in varus loading. It was 0.5 (N/mm) stiffer and 1.8 (N·m) stronger than the internal joint stabilizer (IJS) by difference of medians (p < 0.05).

CONCLUSIONS

Biomechanical and clinical outcomes show that EJS-E via the posterior approach can restore mobility and stability in all patients, thus serving as a valuable alternative option for the treatment of persistent instability of the elbow.

Unique indications for internal joint stabilizer for elbow instability

BACKGROUND

Treatment of elbow instability remains challenging despite advancements in surgical techniques. The objective of this study was to evaluate obesity, advanced age or frailty, and altered cognitive function (because of mental handicap, stroke, dementia, or traumatic brain injury) as unique indications for the use of the internal joint stabilizer (IJS) to augment surgical treatment of elbow instability.

METHODS

This was a retrospective review of all patients 18 years and older with elbow instability who were managed with an IJS along with standard measures of care for their specific injury, such as fracture fixation and collateral ligament reconstruction. Patients were excluded if they did not have a minimum follow-up of 3 months. All patients were treated by a single shoulder and elbow fellowship-trained orthopedic traumatologist at an urban university-based level 1 trauma center.

RESULTS

Twenty-two patients were included in the study. Five patients were 60 years of age or older. Nine patients had a body mass index of 30 or greater. Five patients had a history of 1 or more cerebral insults or cognitive impairment. The majority of patients (21/22; 95%) regained elbow stability after the index surgery. At last follow-up, 14 of 22 patients (63%) regained a functional arc of motion, defined as at least 100° arc of motion, and 77% of patients had at least 90° of motion. Complications requiring revision surgery included culture-negative recurrent elbow instability (n = 1), deep infection (n = 1), and IJS failure without recurrent instability (n = 1). The IJS was removed in all 3 cases. Twelve patients underwent delayed IJS removal >2 months after the index surgery to grant additional time for bony and ligamentous healing and to permit secondary contracture release at the time of IJS removal. No complications were seen from delayed IJS removal.

CONCLUSION

The IJS may be used to create elbow stability in complex patients, regardless of weight, frailty, cognitive function, neurologic insult, or other comorbidities. Unlike external fixation, the IJS does not require pin site care and is relatively light and low-profile. When augmenting surgical fixation for elbow instability, the IJS may be preferable for patients with complex comorbidities or social dynamics.

Proximal ulna fractures in adults: A review of diagnosis and management

Proximal ulna fractures are relatively common upper limb injuries, which may represent fragility fractures or result from high-energy trauma. These include fractures of the olecranon, coronoid and associated radial head dislocations. A wide variety of treatment options are available for the management of these injuries that makes the selection of most appropriate treatment difficult. We aim to provide a brief overview of the treatment options for such injuries.