Transcondylar distal humeral fracture is characterized by a transverse fracture line from the lateral epicondyle just proximal to the capitellum, extending to the medial epicondyle at the level of the olecranon and coronoid fossae [1]. It is a relatively rare type of fracture that accounts for less than 9% of all distal humeral fractures [2-4]. It mainly occurs in elderly patients with osteoporosis due to low-energy injuries [5]. As the fracture site is located inside the joint capsule, nonunion occurs frequently [6,7]. Therefore, displaced transcondylar fractures are absolute indications for surgical treatment. For non-displaced transcondylar fractures, surgical treatment is relatively indicated. Cast immobilization as a conservative treatment can be an option for non-displaced transcondylar distal humeral fractures, but elbow joint stiffness may occur owing to prolonged immobilization [8,9].

Because the distal fragment is small and surrounded by articular cartilage, the bone stock available for internal fixation is small [1,2,10-12]. Due to these anatomical characteristics, it is difficult to rigidly fix distal fragments by internal fixation. Some studies have reported that total elbow arthroplasty is a more useful procedure for articular comminuted distal humeral fractures [13,14]. In transcondylar fractures, however, an osteosynthesis method is a preferred treatment option [15].

With the recent advancement of the pre-contoured locking plate in distal humeral fractures, orthogonal or parallel pre-contoured anatomical locking plate has become the most commonly used implant for distal humeral fractures during the past decade [16]. For transcondylar fractures, open reduction and internal fixation with these plates have reported favorable outcomes [17]. Orthogonal locking plate showed 50% higher stiffness than conventional dorsal two plates and 26% higher stiffness than locking dorsal two plates [18]. Parallel locking plate systems showed greater or equal stiffness than orthogonal locking plates in many studies [19,20]. To fix this pre-contoured anatomical locking plate, the olecranon osteotomy approach and extensor-sparing paratricipital approach are commonly used approaches [3]. Triceps-reflecting anconeus pedicle and triceps-splitting approach are rarely used. However, these approaches require ulnar nerve release and violation of the triceps mechanism interfering with postoperative rehabilitation [3,21]. Additionally, these approaches also require extensive surgical exposure that compromises biological integrity, which may increase the risk of delayed union or nonunion [3,22].

To avoid extensive surgical dissection, two crisscross screw fixations using the medial and lateral incision in elderly patients have been tried and reported favorable outcomes [2]. As part of a minimally invasive surgical approach, tension band wiring (TBW) using a medial and lateral approach has also been attempted. However, it has been reported that this is a risk factor for nonunion compared to rigid fixation using a plate [7].

We performed bilaterally locking anatomical plate fixation using a medial and lateral approach for transcondylar distal humeral fractures without ulnar nerve release or extensive surgical dissection. This study aimed to describe our surgical technique and report the clinical outcomes achieved by using the technique.

The mean operative time was 112±13.5 minutes (range, 80–130 minutes). The mean follow-up duration was 18±7.6 months (range, 12–36 months). Rigid fixation was achieved immediately after internal fixation and was confirmed intraoperatively in all patients. On postoperative radiography, the anatomical reduction was achieved, and there was no step-off of >2 mm in any patient. Bone union was achieved in all patients. There were no remarkable postoperative ulnar nerve symptoms in any of the 18 patients.

In 16 patients without arthritis, at follow-up of 1 year after surgery, the mean VAS score was 0.44±0.7 (range, 0–2). The mean ROM of the elbow joint showed an extension of 13.5°±4.5° (range, 5°–20°) and flexion of 132.0°±7.1° (range, 120°–140°) (Figs. 3). Supination and pronation of the elbow joint were normal in all the patients. The MEPS was excellent for nine patients and good for seven. The mean period of bone union confirmation on the follow-up X-ray was 6.8±0.98 weeks postoperatively. There were no complications such as heterotopic ossification, infection, re-displacement, or hardware failure. In one case, hardware irritation occurred, and the plate was surgically removed 1 year postoperatively.

In one patient with osteoarthritis of Kellgren-Lawrence grade 3, at follow-up of 1 year after surgery, the VAS score was 0, and the ROM of the elbow joint was an extension of 30° and flexion of 125°. Bone union was achieved at 9 weeks, and no complications as mentioned above were observed.

In another patient with rheumatoid arthritis and liver cirrhosis, at follow-up 1 year after surgery, the VAS score was 4, and the ROM of the elbow joint was an extension of 30° and flexion of 150°. Bone union was achieved at 7 weeks, and no complications as mentioned above were observed until 3 years after surgery.

For the treatment of transcondylar fractures in the elderly population, dual-plate fixation using the medial and lateral approach showed excellent clinical outcomes, with all cases achieving an MEPS grade of good or higher. Bone union was achieved in all cases without severe complications. The brief comparison of clinical results and complication rates of transcondylar fractures with literature is shown in Table 1.

Several efforts to obtain rigid fixation via plating and achieve bone union in patients with transcondylar humeral fractures have been made. In 2005, Imatani et al. [10] applied a custom AO small T plate to 17 patients aged ≥70 years and reported bone union in all patients. Then, several studies have reported a high union rate with plate fixation. In 2014, Simone et al. [17] performed plate fixation in 14 patients with transcondylar humeral fractures and achieved bone union in 12 cases. But reported complications in 50% of all patients including two cases of delayed union, heterotrophic ossification, and skin defect. The team applied triceps-sparing, triceps tongue, or olecranon osteotomy approaches. In 2014, Leigey et al. [23] performed bicolumnar 90–90 plating and additional mini-plating on 15 elderly patients with low-energy transcondylar humeral fractures, and bone union was achieved in 14 patients with a joint ROM of 105° (range, 70°–140°). They applied the triceps-reflecting approach in 10 patients and olecranon osteotomy in five patients and reported a single case of ulnar neuropathy. Since the introduction of the anatomical pre-contoured locking LCP in the middle of the 2000s, orthogonal or parallel dual anatomical locking LCP fixation has been adopted as the standard method in the treatment of distal humeral fractures [16,24,25]. In 2020, Sur et al. [15] performed 11 orthogonal and six parallel anatomical LCP dual plating in patients with transcondylar fractures, and bone union was achieved in 16 of the 17 patients, with a single case of nonunion. Therefore, they suggested that open reduction and internal fixation with anatomical LCP could be useful surgical methods to treat transcondylar humeral fractures. They used the triceps-sparing, modified triceps tongue, or olecranon osteotomy approach, with ulnar nerve transfer surgery performed in nine patients but not in eight; they encountered a single case of ulnar neuropathy. For plate fixation for transcondylar humeral fractures, a posterior approach, such as paratricipital, triceps-sparing, or olecranon osteotomy, may be used during surgery. This entails the possibility of ulnar nerve release, which can lead to ulnar neuropathy. Furthermore, triceps weakness may result from a triceps muscle injury or olecranon osteotomy, necessitating a delay in rehabilitation. Moreover, extensive dissection around the elbow joint during plate fixation can cause heterotrophic ossification and prevent biological fracture healing [17].

Efforts have been made to achieve bone union in elderly patients with transcondylar humeral fractures with minimally invasive fixation. Simple percutaneous K-wire pinning, commonly used for pediatric supracondylar fractures, is minimally invasive but not suitable for adult transcondylar fractures because it cannot provide rigid internal fixation for a sufficient period of time. Park et al. [2] applied less invasive cross-type cannulated screw fixation after fracture reduction in 10 patients with transcondylar humeral fractures and achieved bone union in all 10 patients with an outstanding result of 12°–125° mean ROM. Paryavi et al. [8] treated four geriatric transcondylar patients with two-column screws and reported 92° of the arc of motion and achieved bone union in all patients. In both studies, no complications related to surgical approaches were reported. Previous biomechanical studies have shown that plate fixation is significantly more rigid than crisscross screw fixation for transcondylar fractures. Shimamura et al. [26] compared various fixation techniques, including orthogonal dual plating and crisscross screw fixation. The authors reported that crisscross screw fixation has a significantly lower failure load than plate fixation. Ku et al. [7] analyzed nonunion rates of dual plate, single plate, and bilateral TBW in transcondylar humeral fractures. Bilateral TBW was a risk factor for nonunion and dual plate shows the highest nonunion rate. Until now, parallel or orthogonal dual anatomical locking LCP fixation has been the most reliable way to achieve bone union despite several complications resulting from the extensive surgical approach.

We considered a rigid fixation and minimally invasive technique that could help rehabilitation and promote biological fracture healing without necessitating ulnar nerve release or transposition and attempted dual plating using medial and lateral approaches. This technique did not cause any splitting or damage to the triceps muscle, and the medial approach did not require ulnar nerve release or transposition. All 16 patients were older adults with osteoporosis, and dual-plate fixation led to reliable fixation. Illical et al. [27] reported that 89% of triceps strength is preserved after the triceps-sparing approach. In this study, triceps strength was not measured, suggesting the necessity for further studies for comparison. All patients had a complete bone union, with no nonunion or delayed union. Ulnar neuropathy did not occur postoperatively. In this study, fracture reduction and fixation were performed without exposing the anterior and posterior articular surfaces of the elbow joint. This allowed maximum blood flow through the fracture fragment to be maintained, which may have contributed to the prevention of complications such as heterotopic ossification, nonunion, and delayed union. Xie et al. [28] reported a combined medial and lateral approach and bicolumnar plate fixation in 19 patients with AO/OTA type C distal humeral fractures and achieved fracture union in all 16 patients with a mean arc of motion of 113.4°. They used a bendable locking plate, which was different from the pre-contoured anatomical locking plate used in our study.

Since the prevalence of Kellgren-Lawrence grade 3 or 4 elbow osteoarthritis exceeds 10% in the population aged 50 years and older, transcondylar fractures accompanied by osteoarthritis may not be uncommon. For transcondylar distal humeral fracture in patients with rheumatoid arthritis and osteoarthritis, this dual-plate fixation using a medial and lateral approach appears to be an effective treatment option, although total elbow arthroplasty is another treatment option for patients with arthritis and transcondylar fracture. Two patients with arthritis had extension limitations at postoperative 1-year follow-up, but flexion limitations were not remarkable. According to the patients’ memory, a similar degree of extension limitation was present even before the fracture.

One concern with this procedure is that, if nonunion or other complications occur and total elbow arthroplasty is required, total elbow arthroplasty cannot be performed through medial and lateral incision. A posterior approach or other new incisions may be required, but the distance from the existing incision might be too close. To address this concern, further case reports are required.

This study has several limitations. First, the sample size was small and the study was designed as a retrospective study. This limitation implicates a lack of randomization. Second, the selection bias can occur due to exclusion criteria. This limitation narrows the indications and makes it difficult to apply this technique to more complicated cases. Third, a control group was not established. A comparison with the literature is described in Table 1. However, it is not a direct comparison within a single study. Fourth, as parallel plating and orthogonal plating were not analyzed separately, which plating method is better has not been determined between parallel and orthogonal, although the authors prefer parallel. In order to overcome the limitations, further studies with larger sample sizes and comparisons should be conducted.

In transcondylar distal humeral fractures, a medial and lateral approach and bicolumnar dual pre-contoured locking LCP fixation were determined to be a treatment option with favorable clinical outcomes in this small retrospective case series. This method has the advantage of reliable rigid fixation and early ROM without necessitating ulnar nerve release and extensive dissection. Further research with a larger sample size and comparison between treatment options should be conducted to find optimal treatment.