Abstract
Background
Varus-posteromedial rotatory instability (VPMRI) of the elbow is a relatively uncommon yet significant injury that can often present with subtle clinical symptoms, such as mild joint misalignment. These initial symptoms may be easily overlooked or misdiagnosed, especially in the absence of overt signs of instability. As a result, the injury is frequently missed in early stages, leading to improper or delayed treatment. If left untreated, VPMRI can result in severe long-term complications, including rapid joint degeneration, traumatic arthritis, heterotopic ossification, elbow stiffness, and ulnar nerve entrapment. The progressive nature of these issues can lead to permanent functional impairment and reduced quality of life.
Methods
A comprehensive literature review was performed to investigate the study objective.
Results
By examining both conservative and surgical interventions, the review provides a comprehensive understanding of this injury, emphasizing the importance of early diagnosis and appropriate management. Understanding the specific forces involved, such as axial loading, varus stress, and forearm pronation, is crucial for developing effective treatment strategies.
Conclusion
Early intervention can prevent long-term complications and improve functional outcomes, making timely and accurate diagnosis essential for optimal care.
Keywords: Elbow joint, Varus-posteromedial rotatory instability, Diagnosis and treatment, Research status
1. Introduction
Varus-posteromedial rotatory instability (VPMRI) of the elbow is a clinically significant injury pattern that remains relatively under-recognized. It typically results from a combination of axial loading, varus stress, and forearm pronation, often sustained during a fall on an outstretched hand.1 This mechanism can lead to failure of the lateral ulnar collateral ligament (LUCL) and fracture of the anteromedial facet (AMF) of the coronoid process, resulting in recurrent elbow instability.2 Unlike a simple dislocation, the humeroulnar joint in VPMRI may appear deceptively aligned on standard radiographs, with instability manifesting primarily as a dynamic posteromedial rotatory subluxation. This subtle presentation, coupled with occasional olecranon fractures, frequently leads to misdiagnosis or delayed diagnosis.3 If not properly managed, VPMRI can progress to debilitating secondary complications, including post-traumatic arthritis, coronoid nonunion, chronic elbow stiffness, and heterotopic ossification.3
Given these diagnostic challenges and the potential for poor long-term outcomes, a clear synthesis of current evidence is crucial. Therefore, this review aims to: (1) analyze the contemporary evidence on the biomechanics, diagnostic workup, and treatment outcomes of VPMRI; (2) synthesize a practical, evidence-informed decision framework to guide management from diagnosis through rehabilitation; and (3) identify persistent knowledge gaps to inform future clinical research. By addressing these objectives, we seek to enhance recognition and optimize the clinical management of this complex elbow injury.
2. Materials and methods
This study is a narrative review that employed a systematic literature search strategy to synthesize current evidence on the biomechanics, diagnosis, and management of varus-posteromedial rotatory instability (VPMRI) of the elbow. The methodology was designed to ensure comprehensiveness, transparency, and reproducibility.
2.1. Literature search strategy
A comprehensive electronic literature search was conducted across three primary databases: PubMed/MEDLINE, Web of Science (Core Collection), and EMBASE. The search timeframe encompassed all records from database inception until April 2024. To capture all relevant literature, the search strategy utilized a combination of Medical Subject Headings (MeSH) terms and free-text keywords, connected with Boolean operators (AND, OR). Key search terms and concepts included: “varus posteromedial rotatory instability”, “VPMRI”, “posteromedial rotatory instability”, combined with specific anatomical and pathological terms such as “anteromedial coronoid facet fracture”, “lateral ulnar collateral ligament”, “LUCL”, “medial collateral ligament”, and “MCL”. The search was restricted to studies published in English involving human subjects. Google Scholar was used in a supplementary role for citation tracking and to identify any additional grey literature not indexed in the primary databases.
2.2. Study selection and eligibility criteria
Two authors independently screened the titles and abstracts of identified records, followed by a full-text assessment of potentially eligible articles. Discrepancies were resolved through discussion and consensus.
The review focused on adult populations (≥18 years). Included study designs comprised systematic reviews, meta-analyses, prospective or retrospective cohort studies, and case series with a minimum of 5 patients. Studies were required to report on the etiology, diagnostic methods, treatment options, or clinical outcomes of VPMRI.
Exclusion criteria were: (1) studies focusing exclusively on other elbow instability patterns (e.g., “terrible triad”) without specific analysis of VPMRI; (2) purely biomechanical or cadaveric investigations, unless they provided fundamental insight into injury mechanics directly relevant to clinical understanding; (3) conference abstracts, editorials, commentaries, and non-peer-reviewed literature; (4) case reports with fewer than 5 cases; and (5) duplicate publications.
3. Results
3.1. Mechanism of injury
The primary stabilizing structures of the elbow joint include the coronoid process, the humeroulnar joint, and the lateral (LCLC) and medial collateral ligament complexes (MCLC). Secondary stabilizers comprise the radial head, common flexor and extensor tendons, and the joint capsule. VPMRI is typically caused by axial compression combined with varus and pronation forces. Specifically, when the upper limb is extended and the shoulder joint is externally rotated, axial pressure is exerted onto the palm during a fall. This results in increased load on the elbow, causing inward rotation and backward forearm rotation. Consequently, the lateral collateral ligament complex (LCLC) may avulse from the humeral epicondyle, and a medial impact may cause anteromedial fractures of the coronoid process and tears in the MCLC.4
3.2. Coronal fracture types
The coronoid process plays a critical role in elbow stability, and fractures of this structure are common in elbow injuries. The coronoid has two prominent features: the tip, located on the anterolateral surface, and the towering tubercle, located medially. Coronal fractures are classified based on their location and size, with two major systems in use: (1) Regan-Morrey classification,5 which divides fractures into: Type I (avulsion of the coronoid tip), Type II (fracture involving <50 % of the coronoid), and Type III (fracture involving >50 % of the coronoid). (2) O'Driscoll classification,6 which focuses on the location of the fracture fragment, dividing them into three main types: coronoid tip fractures, anteromedial facet fractures, and basal coronoid fractures. The anteromedial facet can be further subdivided into three subtypes: marginal fractures (Subtype 1), marginal + tip fractures (Subtype 2), and marginal + anteromedial facet fractures, with or without tip fractures (Subtype 3). In cases of VPMRI, approximately 93 % of axial forces are transmitted through the humeroulnar joint, which can cause the coronoid's anteromedial facet to fracture, particularly in the absence of adequate support from the proximal ulna.7 The O'Driscoll classification is widely used for these types of injuries,8 which can involve the anteromedial border (subtype 1), or the tip of the coronoid, comminuted fractures (subtype 2), or the towering tubercles and medial collateral ligaments (subtype 3).
3.3. Diagnosis of elbow varus-posteromedial rotatory instability
3.3.1. Clinical manifestation
Patients with VPMRI typically present following an acute injury with the elbow held in a pain-guarded flexed position, accompanied by significant peri-elbow swelling and tenderness. Ecchymosis may be evident, particularly over the medial aspect, while point tenderness is often most pronounced over the lateral epicondyle, corresponding to the common site of lateral ulnar collateral ligament (LUCL) insufficiency.9 Physical examination is critical but may be limited by pain in the acute setting. The hallmark finding is reproducible varus and posteromedial rotatory instability. This can be elicited by performing a varus stress test with the elbow in slight flexion (approximately 20°–30°) to unlock the olecranon from its fossa. A more specific maneuver, the posteromedial rotatory stress test, involves applying a combination of axial loading, varus moment, and forearm pronation to the partially flexed elbow; a positive test is indicated by the palpable or visible subluxation of the proximal ulna relative to the trochlea.10 Due to the frequent preservation of humeroulnar alignment on standard radiographs, a high index of suspicion combined with a meticulous physical exam (potentially requiring examination under anesthesia) is essential to avoid missed diagnosis.
3.3.2. Imaging examination
3.3.2.1. X-ray
Standard anteroposterior (AP) and lateral radiographs of the elbow are the essential initial imaging studies. Key radiographic signs suggestive of VPMRI on the AP view include asymmetrical widening of the lateral humeroradial joint space, indicative of varus alignment, and the presence of an anteromedial coronoid facet fracture fragment.3,9 The lateral view is crucial for assessing the humeroulnar relationship; findings may include subtle posterior subluxation of the radial head, a non-concentric joint, and the visualization of coronoid fractures. Although these fractures are often small, a careful search for the “double line sign”—representing a displaced subchondral bone fragment—can be a valuable clue.11 It is critical to note that due to the dynamic nature of VPMRI and the frequent preservation of gross joint alignment, standard radiographs may appear deceptively normal, underscoring the need for a high index of suspicion and advanced imaging when clinical findings are suggestive.
3.3.2.2. CT scan
CT imaging, including both two-dimensional and three-dimensional (3D) reconstructions, is invaluable in assessing coronoid fractures. It can reveal free fragments of the anteromedial coronoid process and provide detailed views of the fracture's size, displacement, and impact on the articular surface.
3.3.2.3. MRI
MRI is useful for evaluating the integrity of soft tissues such as the MCLC, LCLC, and flexor tendons. It can also show signal changes in the cartilage and ligaments due to injury. However, due to significant edema in acute injuries, it is often difficult to differentiate normal from injured soft tissue structures in the early phase of injury.
3.3.2.4. Ultrasonography
Ultrasonography can effectively assess ligament injuries, including the LCLC and MCLC. Dynamic ultrasound can detect increased ligament laxity, a hallmark of varus-posteromedial rotatory instability.
3.3.2.5. Fluoroscopy under anesthesia
Fluoroscopy, performed under anesthesia, is useful for confirming instability. Stress tests during fluoroscopy can help visualize the extent of instability during surgical planning.
3.4. Treatment of elbow varus-posteromedial rotatory instability
3.4.1. Conservative treatment
In the acute phase, the primary challenge is the patient's pain, which limits physical examination. Some studies suggest that examination under anesthesia is more reliable in these cases.10 Conservative management is appropriate for patients with small fracture fragments (<5 mm) and no detected instability on varus stress testing. Rhyou et al.12 emphasized the utility of fluoroscopic guidance to assess the size of fractures and make decisions regarding conservative treatment. In a study by Chan K et al.,13 10 patients with anteromedial fractures were treated conservatively with closed reduction and plaster immobilization, and after 50 months of follow-up, most achieved satisfactory clinical outcomes. However, conservative treatment carries risks, including habitual instability and early progressive osteoarthritis.14 Park et al.15 found that loss of integrity in the LCLC or coronoid process increases susceptibility to early osteoarthritis. Chan K et al.13 screened several patients undergoing closed reduction splinting and the following conclusions were obtained from an observational analysis of the patients for about 5 years: the average displacement of the fracture fragment was (3 ± 2) mm, the range of motion of the affected elbow was 137° ± 8°, and the mean MEPS was 94 points. Foruria AM et al.16 screened several patients with acute solitary coronary fractures and found that in the presence of an intact coronal nodule, conservative treatment can be applied in any case as long as the height of the fracture fragment is less than 50 %, and the vast majority of patients have very good treatment outcomes. Liu Tao et al. from Qilu Hospital treated and followed up 15 cases of elbow varus-posteromedial rotatory instability injury, and found that the effect of conservative treatment in such patients was not clear. And conservative treatment could only be chosen when the anterior medial surface bone of the coronal process was very small, the position was in a normal anatomical position and the elbow joint did not appear dislocated or subluxated. Therefore, conservative treatment can be considered for patients with simple O'Driscoll type I coronoid fracture who have stable elbow joint on imaging and physical examination. If it is found to have affected the stability of the elbow joint, surgery is recommended. In general, the goals of treatment for traumatic complex elbow instability are to restore a stable rostral notch and maintain proper joint alignment while the collateral ligaments heal.17 If these goals can be achieved with only a brief immobilization of the elbow, nonoperative treatment may be considered. Otherwise, surgical treatment is required to prevent elbow instability and post-traumatic joint necrosis.
3.4.2. Surgical treatment
3.4.2.1. Selection of surgical approach
The choice of surgical approach depends on the size and morphology of the coronoid fracture. Approaches can be posterior, lateral, or anteromedial. Feng et al.18 adopted an anteromedial approach to expose the anteromedial aspect of the coracoid process, which allowed the fracture fragment to be fixed with resurfacing plate screws under direct visualization. Meanwhile, Chen et al.19 compared the treatment effects of coronal fractures with a prospective study on medial and anterior approach, and found that: the duration of the anterior approach, the amount of intraoperative bleeding, and intraoperative trauma were less than that of the medial approach. At present, there are some shortcomings in the lateral and posterior approach and the medial approach, such as the lateral and posterior approach cannot adequately expose the coronoid fracture and the trauma is large, so it is extremely challenging for internal fixation. However, the incision of medial approach is not conducive to recovery, and the injury rate of ulnar nerve and flexor tendon are high. Therefore, The anteromedial approach is often favored as it provides optimal exposure of the coronoid process, with minimal trauma to surrounding tissues and easier fixation.19, 20, 21
3.4.2.2. Selection of fixation method
Fixation of coronoid fractures is typically achieved through internal fixation (e.g., plates, screws, or Kirschner wires) or external fixation. Iannuzzi et al.22 found that screw fixation offers superior stiffness and strength compared to suture lasso techniques for type II fractures. For comminuted fractures, Shen et al.23 demonstrated that microplate fixation can result in good clinical outcomes without complications such as post-surgical instability. At present, most scholars recommend repair of the LCLC to restore the elbow varus and rotational stability, and to perform the elbow valgus stress test again after strong internal fixation of the coronary fracture fragment and repair of the LCLC, and repair of the MCLC is required if the elbow is still unstable.24 In addition, with the development of arthroscopic technology, Kim et al.25 used arthroscopic techniques to repair the collateral ligament of 13 patients with posterior medial rotatory instability of the elbow joint, with an average follow-up of 18 months, and the average postoperative MEPS score was 92, with 12 cases being excellent and 1 case being good.
3.4.3. Postoperative rehabilitation
The core goal of postoperative rehabilitation for varus-posteromedial rotatory instability (VPMRI) is to restore knee stability, improve range of motion, regain muscle strength, and prevent re-injury. In the early postoperative phase, the focus is on reducing swelling and restoring basic joint range of motion, typically through measures like icing, compression, and elevation, while gradually initiating passive and active knee flexion and extension exercises. In the mid-phase of recovery, as swelling decreases and range of motion improves, rehabilitation shifts to strengthening the quadriceps and hamstrings to enhance knee stability and control, with gradual progression to weight-bearing exercises to improve the joint's load-bearing capacity. In the later postoperative phase, the focus is on functional training, such as dynamic balance and explosive power exercises, to help patients regain their athletic capabilities and reduce long-term instability, while gradually reintroducing high-intensity activities like running and jumping. Through this staged rehabilitation approach, patients can effectively restore normal knee function and reduce the risk of chronic knee pain and instability.
4. Discussion
Varus-posteromedial rotatory instability (VPMRI) represents a clinically significant injury pattern that is frequently under-recognized due to its subtle initial presentation and the frequent preservation of humeroulnar alignment on standard radiographs.3 This diagnostic pitfall underscores the necessity of understanding its characteristic biomechanics—a combination of axial loading, varus stress, and forearm pronation—which typically results in failure of the lateral collateral ligament complex (LCLC, primarily the LUCL) and fracture of the anteromedial facet of the coronoid process.1,2 While standard radiographs may reveal indirect signs, computed tomography (CT) with three-dimensional (3D) reconstruction is the gold standard for precisely characterizing coronoid fracture morphology, size, and displacement, which is critical for surgical planning.6,8 Magnetic resonance imaging (MRI) excels in evaluating concomitant soft-tissue injuries to the LCLC and medial collateral ligament (MCL), although acute edema can sometimes obscure interpretation. Complementary dynamic modalities, such as stress fluoroscopy (often under anesthesia) and ultrasonography, are invaluable for directly demonstrating latent instability not apparent on static images.10,11 A high index of suspicion, coupled with a stepwise imaging protocol, is paramount for timely diagnosis.
Management of VPMRI must be individualized, hinging on a triad of factors: fracture morphology (guided by the O'Driscoll classification), the degree of joint instability, and the integrity of ligamentous stabilizers.6,14 Truly non-operative management is reserved for a narrow subset: minimally displaced O'Driscoll type I fractures (or selected, non-displaced type II) in patients who demonstrate unequivocal stability on examination under anesthesia with stress fluoroscopy.12,13 However, long-term data indicate that even in carefully selected cases, risks of residual instability and accelerated post-traumatic osteoarthritis persist, mandating cautious patient selection and thorough counseling.14,15 The presence of displacement, comminution, or any objective instability constitutes a clear indication for surgical intervention to restore anatomy and stability.
When surgery is indicated, the primary goals are anatomic reduction and stable fixation of the coronoid fragment, followed by repair of the incompetent lateral ligamentous complex. The anteromedial surgical approach is widely favored as it provides direct visualization of the fracture with minimal soft-tissue dissection, facilitating accurate fixation.18, 19, 20 The choice of fixation depends on fragment size and comminution: lag screws are optimal for simple fragments, while mini-fragment or pre-contoured plates provide better stability for comminuted fractures.22,23 Concurrent repair of the LUCL is essential to address the varus and rotatory instability component.24 If instability persists after coronoid fixation and lateral-sided repair, attention must be turned to the medial side, with possible repair or reconstruction of the MCL. Although emerging, arthroscopic techniques for these repairs remain technically demanding and are applicable only in selected scenarios.25
Acknowledging potential complications is crucial for surgical planning and patient counseling. Common issues include residual elbow stiffness, symptomatic hardware, and ulnar neuropathy. The most concerning long-term sequelae are persistent instability and post-traumatic osteoarthritis, which are often linked to delayed diagnosis, inadequate fracture reduction, or failure of ligament healing.14,15 Heterotopic ossification is another recognized risk, particularly after extensive surgical dissection. These potential outcomes highlight the importance of anatomic restoration, stable fixation, and early, controlled mobilization.
Structured rehabilitation is a cornerstone of successful outcomes. The protocol must balance early motion to prevent stiffness with adequate protection to allow ligament and bone healing. Typically, an initial phase of short-term immobilization (≤2 weeks) is followed by progressive, active-assisted range-of-motion exercises in a protected arc. Strengthening is introduced gradually after radiographic evidence of union, typically by 8–12 weeks. The entire process requires close supervision to tailor the progression to the individual patient's healing response and stability achieved intraoperatively.
Despite synthesizing the available literature, this review highlights that current evidence on VPMRI is largely derived from retrospective case series and biomechanical studies, constituting a moderate level of evidence. This limits the ability to make definitive, high-strength recommendations. There is a clear need for prospective, multicenter studies with standardized outcome measures (e.g., MEPS, patient-reported outcomes, radiographic parameters) to validate the proposed treatment algorithm. Future research should also explore the role of advanced imaging biomarkers, refine minimally invasive (including arthroscopic) techniques, and investigate biological augmentation to improve healing.
5. Conclusions
In summary, varus-posteromedial rotatory instability (VPMRI) of the elbow is a complex injury that is frequently overlooked due to its subtle initial presentation. Successful management underscores the imperative for a high index of clinical suspicion, a meticulous imaging assessment protocol incorporating dynamic studies where indicated, and a treatment strategy rigorously individualized to fracture pattern and ligamentous integrity. While early diagnosis and appropriate intervention are pivotal for mitigating the risk of long-term complications such as chronic instability and post-traumatic arthritis, it must be acknowledged that the current evidence, predominantly from retrospective series, imposes limitations on the strength of recommendations. Therefore, the optimal management of VPMRI will be further refined by future prospective, multicenter studies employing standardized outcome measures to validate diagnostic algorithms and therapeutic protocols.
Funding
No funding was received in support of this project.
Declaration of competing interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Acknowledgments
All authors who have contributed to the manuscript must be acknowledged.
References
- 1.Cho C.-H., Kim J.-H., Kim B.-S., et al. Pure varus posteromedial rotatory instability of the elbow: radiographic findings, treatment, and outcomes. Injury. 2024;55(8) [Google Scholar]
- 2.Marinelli A., Guerra E., Rotini R. Elbow instability: are we able to classify it? Review of the literature and proposal of an all-inclusive classification system. Musculoskelet Surg. 2016;100:61–71. doi: 10.1007/s12306-016-0424-1. [DOI] [PubMed] [Google Scholar]
- 3.Furey M.J., White N.J., Strauch R.J. Operative Techniques: Shoulder and Elbow Surgery. 2019. Surgical approaches to the elbow; pp. 433–453. [Google Scholar]
- 4.Kural C., Ercin E., Erkilinc M., Karaali E., Bilgili M.G., Altun S. Bicolumnar 90-90 plating of AO 13C type fractures. Acta Orthop Traumatol Turc. 2017;51(2):128–132. doi: 10.1016/j.aott.2016.09.003. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Regan W., Morrey B. Fractures of the coronoid process of the ulna. J Bone Joint Surg Am. 1989;71(9):1348–1354. [PubMed] [Google Scholar]
- 6.O'Driscoll S.W., Jupiter J.B., Cohen M.S., Ring D., McKee M.D. Difficult elbow fractures: pearls and pitfalls. Instr Course Lect. 2003;52:113–134. [PubMed] [Google Scholar]
- 7.Shukla D.R., Golan E., Weiser M.C., Nasser P., Choueka J., Hausman M. The posterior bundle's effect on posteromedial elbow instability after a transverse coronoid fracture: a biomechanical study. J Hand Surg Am. 2018;43(4) [Google Scholar]
- 8.Chin T.Y., Chou H., Peh W.C.G. The acutely injured elbow. Radiol Clin. 2019;57(5):911. + [Google Scholar]
- 9.Savoie F.H., O'Brien M. Chronic medial instability of the elbow. EFORT Open Rev. 2017;2(1):1–6. doi: 10.1302/2058-5241.2.160037. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 10.Ramirez M.A., Stein J.A., Murthi A.M. Varus posteromedial instability. Hand Clin. 2015;31(4):557. doi: 10.1016/j.hcl.2015.06.005. + [DOI] [PubMed] [Google Scholar]
- 11.Shen L., Yu X., Zhong B., Ding J. A figure-eight suture loop with kirschner wires for fixation of anteromedial coronoid process fractures: a case series. Int J Surg Case Rep. 2017;33:130–134. doi: 10.1016/j.ijscr.2017.02.016. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 12.Rhyou I.H., Kim K.C., Lee J.-H., Kim S.Y. Strategic approach to O'Driscoll type 2 anteromedial coronoid facet fracture. J Shoulder Elb Surg. 2014;23(7):924–932. [Google Scholar]
- 13.Chan K., Faber K.J., King G.J.W., Athwal G.S. Selected anteromedial coronoid fractures can be treated nonoperatively. J Shoulder Elb Surg. 2016;25(8):1251–1257. [Google Scholar]
- 14.Lanzerath F., Hackl M., Wegmann K., Mueller L.P., Leschinger T. The treatment of anteromedial coronoid facet fractures: a systematic review. J Shoulder Elb Surg. 2021;30(4):942–948. [Google Scholar]
- 15.Park S.-M., Lee J.S., Jung J.Y., Kim J.Y., Song K.-S. How should anteromedial coronoid facet fracture be managed? A surgical strategy based on O'Driscoll classification and ligament injury. J Shoulder Elb Surg. 2015;24(1):74–82. [Google Scholar]
- 16.Foruria A.M., Gutierrez B., Cobos J., Haeni D.L., Valencia M., Calvo E. Most coronoid fractures and fracture-dislocations with no radial head involvement can be treated nonsurgically with elbow immobilization. J Shoulder Elb Surg. 2019;28(7):1395–1405. [Google Scholar]
- 17.Ring D., Horst T.A. Coronoid fractures. J Orthop Trauma. 2015;29(10):437–440. doi: 10.1097/BOT.0000000000000326. [DOI] [PubMed] [Google Scholar]
- 18.Feng D., Zhang X., Jiang Y., et al. Plate fixation through an anterior approach for coronoid process fractures A retrospective case series and a literature review. Medicine (Baltim) 2018;97(36) [Google Scholar]
- 19.Chen H., Teng X. A comparative study on the validity and reliability of anterior, medial, and posterior approaches for internal fixation in the repair of fractures of the coronoid process of the ulna. Eur J Med Res. 2018;23 [Google Scholar]
- 20.Huang A.L., Hackl M., Chan A.H.W., Axford D.T., Athwal G.S., King G.J.W. Medial elbow exposure: an anatomic comparison of 5 approaches. J Shoulder Elb Surg. 2021;30(3):512–519. [Google Scholar]
- 21.Yu T., Tao H., Xu F., Hu Y., Zhang C., Zhou G. Comparison of lateral approach versus anterolateral approach with Herbert screw fixation for isolated coronal shear fractures of humeral capitellum. J Orthop Surg Res. 2019;14 [Google Scholar]
- 22.Iannuzzi N.P., Paez A.G., Parks B.G., Murphy M.S. Fixation of regan-morrey type II coronoid fractures: a comparison of screws and suture lasso technique for resistance to displacement. J Hand Surg Am. 2017;42(1):e11–e14. doi: 10.1016/j.jhsa.2016.11.003. [DOI] [PubMed] [Google Scholar]
- 23.Shen J.-J., Qiu Q.-M., Gao Y.-B., Tong S.-L., Huang J.-F. Direct anterior approach for mini plate fixation of regan-morrey type II comminuted ulnar coronoid process fracture. J Orthop Surg. 2019;27(1):1–6. [Google Scholar]
- 24.Ouyang K., Wang D., Lu W., et al. Arthroscopic reduction and fixation of coronoid fractures with an exchange rod-a new technique. J Orthop Surg Res. 2017;12 [Google Scholar]
- 25.Kim J.W., Yi Y., Kim T.K., et al. Arthroscopic lateral collateral ligament repair. J Bone Joint Surg Am. 2016;98(15):1268–1276. doi: 10.2106/JBJS.15.00811. [DOI] [PubMed] [Google Scholar]