Postoperative Outcomes of Anteromedial Approach in Patients with Elbow Varus Posteromedial Rotatory Instability: A Retrospective Study

Introduction

Varus posteromedial rotatory instability (VPMRI) is a distinct type of elbow joint injury, initially described by O’Driscoll as a variant of posterolateral rotatory instability [1]. The injury mechanism primarily involves a fracture of the anteromedial facet of the ulnar coronoid process and damage to the lateral collateral ligament, resulting from axial loading combined with varus and posteromedial rotational forces [2,3]. Coronoid process fractures are systematically categorized by the O’Driscoll classification, which stratifies injuries based on computed tomography (CT) morphological characteristics: Type I involves the coronoid tip (transverse fracture line <50% height), Type II affects the anteromedial facet (oblique fracture plane), and Type III comprises basal fractures (>50% coronoid height). Medial rotatory instability patterns typically correspond to Type II injuries, characterized by anteromedial cortical involvement. This subtype is further differentiated into 3 variants based on associated osseous involvement: Subtype 1 (isolated anteromedial surface), Subtype 2 (anteromedial surface and coronoid tip), and Subtype 3 (anteromedial surface, sublime tubercle, and tip extension) [1].

Varus posteromedial rotatory instability is a rare but clinically significant elbow pathology. Analysis of an epidemiological investigation in the UK (2015–2022) indicates an annual incidence of 303.2 per 100 000 adults for elbow fractures, with VPMRI accounting for 1–2% of these cases. Notably, 2–15% of elbow fractures cases present with concomitant elbow dislocations. Epidemiological data demonstrate a mean age of 48.2 years at injury (male predominance: 56.4%), underscoring the working-age population’s vulnerability. Despite its low overall prevalence (an estimated 3–6 cases per 100 000 population annually), the critical role of the posteromedial complex in elbow stability necessitates prompt surgical intervention to prevent chronic instability and degenerative changes [4].

The key to the treatment of varus posteromedial rotatory instability is reduction of the anterior-medial fracture of the coronoid process. Open reduction and internal fixation is the preferred surgical approach, with evidence suggesting that surgical intervention yields satisfactory outcomes when the coronoid process fracture involves a bone block height exceeding 2.5 mm or 15% of the total coronoid process height [5]. However, the important anatomical structures of the median nerve, ulnar nerve, and brachial artery surrounding the coronoid process complicate the design and selection of surgical approaches. Fracture fragments on the anterior inner surface of the coronoid process are irregular and small; therefore, selection of internal fixation must be made very cautiously.

The surgical approaches for anterior-medial elbow joint injuries can be broadly classified into 2 types: anterior and medial approaches. The medial approach mainly encompasses the Smith approach, the flexor carpi ulnaris (FCU) split approach [6], the Hotchkiss approach [7,8], the Taylor-Scham (T&S) approach [9], and the extended medial epicondylar approach (EMEA) [10,11]. The most commonly used anterior approach is the over-the-top approach [12,13]. Each approach has its own distinct characteristics. The medial Hotchkiss approach has been used in the surgical management of the coronoid process fractures. This technique provides direct visualization of the anteromedial coronoid facet, facilitating anatomical reduction and rigid fixation under direct visualization. However, long incisions, extensive soft-tissue dissection, and surgical incisions near structures such as the flexor tendon, ulnar collateral ligament, and ulnar nerve pose a risk of nerve damage [14].

Because the medial approach provides limited exposure of the anterolateral coronoid facet, some surgeons have used the anterior approach. The anterior approach directly opens the anterior capsule of the elbow joint and allows operating from the space between the biceps brachii muscle and brachial artery, which avoids excessive dissection of muscle and fascial tissue, thereby minimizing iatrogenic trauma to surrounding soft-tissue structures. During the procedure, the biceps brachii is retracted laterally, while the brachial artery and median nerve are retracted medially to facilitate exposure of the anterior column. Studies have demonstrated that this approach effectively reduces fractures, with postoperative elbow MEPS functional scores averaging 98±3.3 points. However, the surgical exposure of the fracture site is relatively limited, and the need to operate between the brachial artery and median nerve elevates the risk of vascular and nerve injury. Consequently, this technique requires orthopedic surgeons to possess advanced anatomical expertise [12,13]. Recent research has shifted the emphasis toward optimizing safety profiles and refining minimally invasive techniques. A modified anterior approach has been developed that uses the nerve plane between the brachial artery and median nerve, in contrast to the conventional anterior surgical approach. This method reduces intraoperative biceps muscle dissection, accelerates postoperative recovery of elbow function, and has lower complication rates, but it increases the risk of iatrogenic neurovascular injury [15].

No consensus or guideline exists for selecting internal fixation methods for coronoid process fractures. Most surgeons use single steel plate fixation. Chen et al found that single steel plate fixation provides sufficient pressure on the fracture fragment [16]. In contrast, Ochtman prefers double-plate fixation, noting that single-direction compression is insufficient, reporting that double-plate fixation stabilized the fracture surface in longitudinal and transverse directions [17]. Zhang Bo and Pai et al recommend use of an anchor instead, and oppose using steel plates for anterior and medial fractures due to the risk of screw penetration and fixation failure [18,19]. Liu proposed combining steel plates with an anchor, integrating the joint capsule, bone fragments, and steel plate into a cohesive structure, similar to our method [20].

From April 2017 to January 2024, this retrospective study evaluated postoperative outcomes and outcomes at 6 months in 9 patients with elbow varus posteromedial rotatory instability following an anteromedial surgical approach using a steel plate and high-strength suture, aiming to provide a reference for the selection of surgical approaches and internal fixation methods for similar injuries. This approach involves accessing the intermuscular space between the pronator teres and the radial wrist flexor to expose and treat the anterior-medial fracture of the coronoid process. To ensure stable fixation of small bone fragments on the anteromedial side of the coronoid process, high-strength sutures combined with contoured steel plates are employed to compress the fragments, limit their displacement, and prevent internal fixation failure. It provides a sufficient anterior-medial surgical field, allowing for better repair of fracture fragments.

Material and Methods

INCLUSION AND EXCLUSION CRITERIA:

The inclusion criteria for this study comprised adult patients aged 18 years or older diagnosed with varus posteromedial rotatory instability, characterized by an anterior-medial coronoid fracture and lateral collateral ligament injury, as confirmed by preoperative elbow joint digital radiography (DR) and computed tomography (CT) scan. Eligible patients had no preoperative vascular or nerve damage or complications such as compartment syndrome. All patients underwent internal fixation surgery using steel plates and high-strength sutures through the anterior-medial approach. All patients completed postoperative follow-up.

Exclusion criteria included multiple fractures of the ipsilateral limb, primary diseases affecting the ipsilateral elbow or wrist joints, pre-injury inability to interact normally, severe degenerative arthritis of the elbow joint, osteoarthritis with functional impairment, a history of rheumatoid arthritis, and old fractures.

SURGICAL PREPARATION:

Upon admission, physical therapy was promptly initiated, encompassing manual reduction and plaster external fixation. Nonsteroidal anti-inflammatory drugs were administered to mitigate swelling and alleviate pain. Additionally, CT three-dimensional reconstruction was utilized to reassess the positioning of fracture fragments and the extent of ligament injuries, thereby informing surgical planning.

SURGICAL PROCEDURE:

The patient is positioned supine and anesthetized using either brachial plexus block or tracheal intubation. The affected limb is abducted and placed on the operating table, with a tourniquet pre-applied to the upper one-third of the arm. An incision is made approximately 1 cm distal to the medial epicondyle of the humerus, following the direction of the pronator teres muscle while avoiding the medial cutaneous nerve and the basilic vein of the forearm. To protect important nerve vessels such as the median nerve and brachial artery, we enter through the intermuscular septum between the pronator teres muscle and the radial wrist flexor muscle, which reduces the risk of exposure. The tendon membrane of the biceps brachii is longitudinally incised, and the intermuscular septum between the pronator teres and the flexor carpi radialis is opened along the muscle fibers and freed. The pronator teres is retracted radially, while the flexor carpi radialis is retracted ulnarly. The brachialis muscle is exposed, and its fibers are incised to reveal the anterior joint capsule. After opening the capsule, the coronoid process of the ulna is exposed. To reduce postoperative complications such as ectopic ossification and elbow stiffness, and ensure a good surgical field of view, we thoroughly clear the hematoma around the fracture. Hematoma and necrotic soft tissue surrounding the fracture site are removed, and the fracture line is fully visualized. Under direct vision, the fracture fragment is reduced. To prevent the failure of internal fixation of small bone blocks, we use high-strength sutures to apply lateral pressure to the small bone blocks. A high-strength suture is first applied to the joint capsule near the coronoid process fragment, tied, and pulled distally to aid in reduction. The fracture is temporarily stabilized using Kirschner wires, followed by the selection of an appropriately sized locking anatomical plate based on the fracture fragment size and degree of pulverization. A 3.5-mm plate can be applied in large fragments, while a 2.0–2.7-mm plate can be applied in a smaller fracture. The plate is contoured and positioned over the coronoid process fracture site, with screws inserted according to the fracture line and plate placement. The high-strength suture is then secured to the lateral hole of the anatomical plate. Intraoperative fluoroscopic elbow joint stress testing is performed; if positive, the anterior-medial incision is extended to repair the medial collateral ligament (MCL). The extent of lateral collateral ligament injury is assessed via varus stress testing, and if necessary, a hole is drilled and repaired using 1 or 2 anchor sutures. If ligament repair is not performed, postoperative brace fixation is applied. Following fracture and ligament repair, the fascia, subcutaneous tissue, and skin are closed in layers. A surgical drain is placed and removed within 24 hours postoperatively.

POSTOPERATIVE TREATMENT AND FOLLOW-UP:

Postoperative management involved the application of sterile drainage strips, which were systematically removed within 24 hours. Imaging assessment, including standard X-ray and CT scans of the elbow joint, was performed on postoperative day 2, concurrent with the initiation of active mobilization exercises for the shoulder, wrist, and finger joints. On postoperative day 3, the forearm was placed in a neutral position with straight extension. Active and passive flexion and extension activities of the elbow joint were initiated. Rotation of the forearm was not allowed. The active range of motion of the elbow joint was 0–30°. One week after surgery, the active range of the elbow joint continued to increase. The surgical sutures were removed 2 weeks later. Rotation of the forearm was allowed 4 weeks later. Following discharge, patients were advised to maintain adherence to prescribed rehabilitation protocols and attend scheduled follow-up evaluations at 1, 2, 3, and 6 months. These evaluations incorporated comprehensive assessment of elbow joint range of motion, surgical site integrity, and radiographic indicators of osseous union, including fracture line resolution and internal fixation stability. Final radiographic evaluations documented obliteration of the coronoid process fracture line, with functional outcomes quantified using the Mayo elbow performance score (MEPS).

MAYO ELBOW PERFORMANCE SCORE (MEPS):

The MEPS was used to assess clinical outcomes. This scoring system evaluates 4 domains: pain (45 points), range of motion (20 points), stability (10 points), and 5 functional daily activities (25 points), including hair combing, eating, personal hygiene, dressing, and putting on shoes. Total scores are categorized into 4 grades: excellent (90–100 points), good (75–89 points), fair (60–74 points), and poor (0–59 points) [21,22].

DATA ANALYSIS:

All analyses were performed using SPSS v27 (IBM Corporation, Chicago, IL, USA). All measurement data are expressed as the mean±standard deviation. For the data to be compared, data are presented as mean±standard deviation or the median (interquartile range) [M (P25, P75)] based on distributional characteristics. Normality was assessed using the Shapiro-Wilk test (α=0.05). For normally distributed data with homoscedasticity (verified by Levene’s test), parametric tests were employed: independent t-tests for between-group comparisons. Non-normal or heteroscedastic data were analyzed using Friedman test (n<30), followed the post hoc analysis by Wilcoxon signed-rank (Holm-Bonferroni) tests when omnibus significance was detected. Holm-Bonferroni correction for multiple comparisons. Statistical significance defined at p<0.05.

Results

PERIOPERATIVE INFORMATION:

The perioperative information comprised 9 patients (6 females, 3 males) with a mean age of 50±22.97 years. At the final follow-up, all patients showed disappearance and healing of fracture lines on X-rays, with fracture healing requiring 7–14 weeks (10.1±2.89). All patients presented with varus posteromedial rotatory instability and were treated by using a steel plate with high-strength suture through the anterior-medial approach. The affected side was the left in 4 patients and right in 5 patients. According to the O’Driscoll classification system, all cases were categorized as type II injuries, consisting of 5 grade 2 and 4 grade 3 types.

INTRAOPERATIVE AND POSTOPERATIVE COMPLICATIONS:

The intraoperative bleeding volume of all patients ranged from 100 to 400 ml (225±84 ml), and surgical time of all patients ranged from 95 to 280 min (224±61 min). Postoperative follow-up ranged from 8.5 to 19.5 months (12.38±3.43 months). Radiographic evaluation confirmed satisfactory fracture reduction and appropriate internal fixation positioning. Two patients developed mild heterotopic ossification (HO) – one anterior-medial and the other posterior-medial – and after manual release therapy, they both had regained proper elbow joint function by the final follow-up. This intervention enhanced elbow range of motion to clinically acceptable levels without requiring additional surgery. No instances of neurological impairment, soft-tissue complications, joint instability, stiffness, or dislocation were observed in the remaining cases.

FUNCTION FOLLOW-UP EVALUATION:

Imaging follow-up demonstrated preserved normal range of motion in all patients’ elbow joints throughout the study period. At final follow-up, all patients’ EMPS ranged from 85 to 100 (92.2±5.07), 8 patients achieved excellent scores and 1 attained good scores, 100% had favorable outcomes. Comparing the EMPS of the patients at 3 time points – preoperative, immediately postoperative, and 6 months postoperative – the preoperative score was 3.33±4.33, and the postoperative score was 41.11±7.81. The EMPS score at postoperative 6 months was significantly higher than the preoperative and postoperative EMPS scores (both p<0.05), as shown in Table 1 and Figure 1. Liu reported similar results of favorable outcomes shown by EMPS scores (83.33%) for coronoid process fractures treated with plate fixation combined with sutures [14].

Elbow flexion ranged from 105° to 140° (121.67±12.24°), while extension ranged from 0° to 20° (6.11±6.13°). Spin forward ranged from 60° to 85° (70.56±8.31°). Spin back ranged from 60° to 90° (70.56±8.64°). General information and postoperative functional outcomes of patients are presented in Tables 2 and 3. A typical case from our study is shown in Figures 2 and 3. The results for the elbow joint discussed above are consistent with the functional improvement observed with Pai’s anchoring technique and Zhang’s surgical treatment for coronoid process fractures [18,19].

Discussion

This study retrospectively analyzed 9 patients with varus posteromedial rotatory instability who received treatment between April 2017 and January 2024. Under direct visualization, a combination of steel plates and high-strength sutures were used through the anteromedial approach to treat varus posteromedial rotatory instability. This technique effectively avoided damage to the median nerve and brachial artery, reduced the need for extensive soft-tissue dissection through long incisions, effectively reduced the risk of internal fixation failure which caused by small bone fragments, avoided nerve and vascular damage, and reduced the occurrence of postoperative complications. The surgical process includes 3 key steps: (1) exposing the fracture surface of the anterior-medial coronal process through the anterior-medial approach, and placing high-strength sutures through the joint capsule at the proximal fracture fragment site; (2) Fracture reduction is achieved by dissecting steel plates and fixing them with appropriate screws; (3) High-strength suture fixation is performed through the side holes of the steel plate to enhance compression between the steel plate and the fracture surface. The follow-up results showed that the fracture healing and functional recovery of all cases were satisfactory. In our study, ectopic ossification of the medial elbow joint was identified in 2 patients at the follow-up, which may have been related to severe injury at the fracture site, caused by varus posteromedial rotatory instability, as well as for the external fixation braces of the elbow joint after injury. The underlying cause of this may be that during the immobilization period following elbow injury, the joint is typically maintained in a 90° flexion position. When the elbow is adducted, the medial aspect of the entire elbow joint becomes the lowest point of the upper limb, causing blood from the fracture site to pool in this area, subsequently leading to ectopic ossification. This finding aligns with the location of ectopic ossification observed in our study and corroborates the results of Meyers, who reported that over 50% of heterotopic ossification (HO) cases occurred in the medial aspect of the elbow in their study of elbow stiffness [23]. To prevent ectopic ossification, we implemented the following preventive measures: 1. Thorough debridement of hematomas at the fracture site during surgery to reduce soft tissue adhesion; 2. Using the internal fixation with steel plate and high-strength suture to stabilize small fracture fragments, prevent micromotion, and provide lateral compression; 3. Early postoperative functional exercises for patients to reduces elbow stiffness. The incidence of ectopic ossification in our final study was 2/9, which is slightly lower than the 1/6 reported by Liu [14]. This suggests that our method can reduce the risk of ectopic ossification and accelerate the recovery of elbow joint function following surgery.

Varus posteromedial rotatory instability is frequently misdiagnosed. When managing O’Driscoll type II coronoid fractures, comprehensive assessment of lateral collateral ligament and medial collateral ligament integrity should be performed to differentiate true medial rotational instability following elbow injury. The primary challenge in treating varus posteromedial rotatory instability through the anteromedial approach stems from preoperative imaging evaluation; expert orthopedic interpretation and surgical visualization are essential for accurate diagnosis, and misdiagnosis can impede optimal treatment planning. Emerging evidence suggests artificial intelligence (AI) could augment diagnostic capabilities. Binh’s meta-analysis demonstrated deep learning models achieve exceptional accuracy (sensitivity: 0.93, 95% CI 0.91–0.96) in pediatric elbow fracture detection (ages 0–16), indicating substantial diagnostic potential [24–27].

The key to treating varus posteromedial rotatory instability is reduction and fixation of anterior-medial fractures of the coronoid process. However, surgical exposure and fixation are complex and challenging due to the irregular fracture block of the coronoid process and the location of important anatomical structures such as the median nerve and brachial artery in front of the elbow joint and the ulnar nerve on the medial side. Consequently, further investigation into optimal surgical approaches and internal fixation techniques for these injuries is crucial [28,29]. Varus posteromedial rotatory instability involves fractures on the anterior-medial surface of the ulnar coronoid process. The bone fragment on the anterior-medial side of the ulnar coronoid process is irregular and small. The lack of lateral compressive strength in plate internal fixation increases the risk of failure of tension screws. Chen et al conducted a comparative study of internal fixation methods in 164 patients with O’Driscoll type II/III coronoid fractures, divided into 4 groups treated with plate fixation, cannulated screws, Kirschner wires, or tension band wiring. Their analysis revealed that plate and screw fixation significantly reduced surgery duration (mean reduction: 28%) and intraoperative blood loss compared to wire-based methods. Furthermore, these rigid fixation techniques demonstrated superior postoperative functional outcomes (MEPS improvement ≥30%) and lower complication rates (12.8% vs 34.1% in wire groups), particularly regarding fracture redisplacement and hardware failure [16]. This discrepancy may stem from the biomechanical limitations of wire fixation in addressing small, comminuted fracture fragments characteristic of varus posteromedial rotatory instability. Kirschner wires and tension bands fail to generate adequate compression, predisposing to micromotion and secondary displacement [30,31]. Traditional mini-fragment plates, while providing axial loading, lack circumferential containment of small fragments (<25% the coronoid height), increasing failure risks in osteoporotic bone or complex fracture patterns [32]. To enhance transverse compression of the fracture fragments, Ochtman employed a second plate applied to the medial coronoid process via an extended medial incision, after initial posteromedial fixation of the olecranon [17]. The approach created a double-plate fixation system. This modification was necessary because a plate extending from the posterior to the anterior aspect is insufficient for compressing the anteromedial coronal process, necessitating additional pressure from a transverse direction. Postoperative follow-up revealed successful fracture healing, with elbow joint motion achieving 115° of extension and 30° of flexion. However, the surgical double-plate internal fixation required extensive dissection of soft tissues, including muscles and fascia, thereby increasing the risk of ectopic ossification and ulnar nerve injury [17]. The range of motion of the elbow joint during their follow-up was similar to our results (extension mean 121.67±12.24°, flexion mean 6.11±6.13°). We used sutures to provide lateral compression without necessitating additional incisions, thereby better preserving soft tissues and preventing ulnar nerve injury. This approach is a safer and less invasive internal fixation method. Flexible fixation techniques can concurrently provide both longitudinal and lateral compression. In a clinical study involving 32 patients with coronoid process fractures, Zhang et al recommended using sutures and suture anchors connected to the joint capsule to fix small bone fragments of the coronoid process. They argued that steel plates are not effective for stabilizing small fracture fragments and reported satisfactory surgical outcomes. The final follow-up elbow joint function score was 91.08±11.68 points. Additionally, this method demonstrated superiority over the use of steel plates alone in terms of intraoperative blood loss (mean 120.83±72.17 ml) and operation time (mean 2.42±0.56 hours) [18]. Our research results were similar in terms of blood loss and operation time. This may be attributed to the use of suture-based internal fixation, which reduces the need for extensive soft-tissue dissection. However, compared to rigid plate fixation, this approach demonstrated prolonged short-term postoperative recovery despite achieving comparable final elbow functional restoration. This discrepancy may be attributed to the lack of strong internal fixation of flexible fixation systems (anchors and sutures) in maintaining fracture stability when compared to plate-based constructs. To improve this internal fixation method, Liu et al reported a hybrid fixation system combining pre-contoured plates and suture anchors, simultaneously stabilizing the joint capsule, bone fragments, and plate structure and enhancing the fracture stability through combined compression and containment mechanisms. Their study enrolled 24 patients with ulnar coronoid process comminuted fractures treated with this method – 83.33% achieved excellent/good MEPS scores, with only 4 cases exhibiting minor soft tissue ossification and no severe complications [20]. The internal fixation method employed in that study is similar to our research, yet the final elbow joint function score was marginally lower. This discrepancy may be attributed to the use of a steel plate and suture anchors in this study. The suture anchors relatively immobilize the brachial-ulnar joint, creating a reciprocal tensile force. If the suture anchors are excessively tight, which can affect the range of motion of the elbow joint. Pai achieved satisfactory results by using anchor fixation to fix the fracture of the coronoid process of the ulna, with an average elbow flexion-extension of 116±10º and an average flexion of 15±10º postoperatively, and there were no significant postoperative complications such as joint stiffness [19]. Our comparative analysis showed superior flexion improvement (6.11±6.13° vs 15±10°) over Pai’s and Zhang’s anchor fixation technique, while extension recovery was comparable (121.67±12.24° vs 116±10°). This differential improvement likely stems from the inherent stability of our hybrid construct, which enabled early mobilization without prolonged external immobilization [18,19]. Postoperative EMPS scores were 85–100 (mean 92.2±5.07), with 100% excellent/good outcomes.

The selection of surgical approach significantly influences postoperative complication rates. Zhou et al developed a minimally invasive anteromedial approach that optimizes visualization of anteromedial coronoid process fragments while minimizing soft-tissue disruption. This technique demonstrated 96% anatomical reduction accuracy through limited subperiosteal dissection, preserving functional elbow mobility (mean flexion-extension arc: 112°±15°) without joint stiffness complications [15]. The anteromedial approach is particularly effective for small coronoid fragments (<15 mm), circumventing the neurovascular injury risks associated with traditional extensile exposures. In a comparative analysis of elbow fracture management, Wang and Zhang found a 10% reduction in postoperative stiffness and heterotopic ossification rates with the anteromedial approach compared to conventional medial approaches [33,34]. This is consistent with our finding in this study that there is no serious ectopic ossification after surgery using the anterior-medial approach. This may be due to the anterior-medial approach we used, dissecting the intermuscular septum between the pronator teres muscle and the radial wrist flexor muscle, without the need for dissection of the median nerve, ulnar nerve, and brachial artery, reducing the detachment of soft tissue from the incision. It also may be because the anterior-medial approach provides a sufficient surgical field on the anterior-medial side before the coronal fracture, so the surgeon does not need to cut so much soft tissue to expose the fracture. These factors result in less soft-tissue damage during surgery, less bleeding, and less risk of ectopic ossification and elbow joint stiffness.

This study has several limitations that should be acknowledged. First, the relatively small sample size, attributable to the low incidence rate, may limit the generalizability of the research findings. In future research, the application of artificial intelligence technology could be explored to further assist in the diagnosis of elbow joint-related injuries and enhance the diagnostic accuracy for such conditions. Second, the follow-up duration might be insufficient to evaluate long-term outcomes. Third, the data analysis was not adjusted for potential confounding factors (eg, patient age, sex, fracture type). These limitations may introduce potential biases in the research conclusions. Fourth, the anterior-medial approach is indicated for anterior-medial coronoid process fractures but is inadequate for purely anterior or medial fractures, which means that preoperative evaluation of fracture morphology is crucial for selecting the appropriate surgical approach. When using a steel plate combined with high-strength sutures for internal fixation, the sutures must be placed before the steel plate, with each secured independently, potentially complicating the intraoperative procedure. Future research should focus on developing a specialized small steel plate integrated with sutures to simplify and streamline the surgical process.

Conclusions

The anteromedial approach combined with high-strength sutures and steel plate fixation demonstrates reliability and efficacy in treating varus posteromedial rotatory instability. This technique has excellent clinical effectiveness, suggesting its utility in the selection of surgical approaches and internal fixation methods for similar types of elbow joint injuries. Additionally, in the future it is necessary to further expand the sample size and ensure a long follow-up time through multi-center research to verify the long-term efficacy found in our study. In future analyses of research results, we will employ multivariate analysis methods to control for potential confounding factors, such as patient age, sex, and fracture type, which will enhance the statistical strength of findings.