The present study demonstrated that the posterior olecranon osteotomy and anterior approach had no significant differences in clinical efficacy and operation-related complications compared to the combined lateral and medial approach. However, the combined medial-lateral approach exposed only 46.9% of the whole distal humeral articular surface, which is lower than the maximal visible size of 61.3% reported for the olecranon osteotomy approach. Another research study has reported that the average percentage of the exposed articular surface for the anterior approach was 45.7% , which is also lower than 53.9% for the olecranon osteotomy. According to our experiences and previous studies[15, 18, 22], it is difficult to entirely expose the complex distal humeral fractures for any single approach, which is insufficient for treatment, especially for severe intra-articular fractures. The anterior (Henry) approach to the elbow has been widely used in upper limb surgery. It has been described as a valuable choice for the synthesis of proximal radial fractures, reinsertion of the distal biceps tendon, excision of anterior elbow tumors, and debridement in case of soft-tissue infections. However, due to the anatomical characteristics of the area and because the elbow can be approached from other directions that involve lower surgical risk, the anterior approach is rarely used in everyday practice. Despite the fact that radial nerve lesions have been reported in association with the approach, we recommend the use of a wide-blade separator to retract the mobile wad of Henry laterally along with the radial nerve, thus minimizing the possible insult to the nerve. Additionally, the anterior approach, which passes through the interval between the brachioradialis and the biceps or the biceps and the medial brachial neurovascular bundle, can avoid releasing the LUCL in combination with the olecranon osteotomy or the lateral approach[9, 25] in situations necessitating anterior exposure, such as a coronal capitellum or trochlear fracture. Because the anterior auxiliary approach combined with the olecranon osteotomy approach can expand the exposure area, it can further assist in the reduction and fixation of the coronal fracture from the front, especially when the patient was positioned supine with the elbow in full extension. This might explain why the incidence of postoperative complications, bleeding volume, and operation duration did not significantly increase in the case of increased olecranon osteotomy and anterior assisted exposure. It has been reported that intra-articular fractures of the distal humerus can be treated with ORIF through a combined medial-lateral elbow approach, which is useful in the surgical treatment of AO/OTA C1 and C2 with a simple fracture pattern in the posterior distal humerus. It also provides better outcomes for the motion of the elbow, bleeding volume in surgery, and complications than olecranon osteotomy[15, 17, 21]. To achieve a good anatomic reduction and stable internal fixation, it is important to gain enough exposure to the articular surface. Despite the fact that a combined medial-lateral approach can keep the integrality of the elbow extensor and, therefore, does not influence the extension power, which can allow patients to exercise early[17, 21], the major exposed area of the combined medial-lateral approach was limited to the front of the distal humeral articular surface compared to the anteroposterior approach. Thus, the P-A approach is recommended to treat complex articular fractures of the distal humerus, particularly the AO/OTA C3.
In the literature on surgical treatment of intra-articular distal humeral fractures, the posterior olecranon osteotomy approach is considered to be a better one, despite significant complications, such as delayed union, non-union, heterotrophic ossification, ulnar nerve paralysis, symptomatic olecranon fixation, and secondary procedures required for the removal of symptomatic hardware having been reported[14, 15, 18, 27, 28]. It is particularly beneficial for fractures with comminution of the articular surface. It also provides a more optimal visualization of distal articular surfaces. Non-union of osteotomy site has been reported to be as high as 30% when transverse osteotomy was performed. However, the risk of potential non-union complication is reduced with the use of a chevron-shaped osteotomy of the olecranon and proper fixation. Coles et al. have reported that delayed fracture union of chevron-shaped osteotomy occurred in only one out of 67 patients, and the union eventually occurred 10 months later after operation without further intervention. Ring et al. have reported union of the osteotomy in 44 out of 45 patients (98%). In the present study, two bicortical K-wires and a tension band construct were utilized to fix the osteotomy site. Only one case (7.7%) of delayed healing occurred in the P-A group, which can be attributed to chevron-type osteotomy on the basis of its larger contact area and better rotational stability compared to the transverse osteotomy. The osteotomy site healed after a prolonged cast fixation, which hints that two bicortical K-wires and a tension band construct were able to securely stabilize the osteotomy site. A recent retrospective review of distal humeral fractures treated via a transolecranon approach during a nine-year period showed that there were no differences in osteotomy time to union, elbow motion, or MEPS at final follow-up in patients with olecranon osteotomy fixed with tension band wiring or plate fixation. As compared with another technique to fix olecranon osteotomy with plates and screws, K-wire/tension band technique has become more popular due to limited surgical exposure and inexpensive implants.
It has recently been reported that the risk of HO development in association with distal humeral fracture includes central nervous system injury, delay in operative intervention, and surgery prior to definitive fixation, but not surgical approach. Thus, the role of the surgical approach in the development of HO remains controversial. No significant difference in HO was shown between the two groups in the present study. To date, there has been no Level 1 evidence examining the role of HO prophylaxis in the management of distal humeral fractures treated with ORIF[7, 9]. Nevertheless, indomethacin was used to prevent the development of HO according to its previously recommended dosage and usage in the present study. HO occurred in two cases (15.4%) in the P-A approach and one case (6.7%) in the L-M approach, which is close to previously reported findings[14, 17, 21]. In accordance with prior studies, the ulnar nerve was routinely anteriorly transposed in the two groups in order to avoid impingement between nerve and implants during elbow motion. The results indicated that only one case (7.7%) developed ulnar nerve palsy among patients treated using the P-A approach, which was considered to be traction injury to the nerve during surgery. Since the implantation of posterior to anterior headless screws into the anterior articular surface could not be directly observed in the L-M group, improper selection could easily lead to irritation symptoms in the posterior elbow joint. In this approach, we reported one case (6.7%) of irritation symptoms caused by the excessive length of the internal fixation screw, which required a second operation to be removed at 5 months post-surgery. Studies have reported that the rate of symptomatic hardware that necessitated re-operation for removal ranges from 8–13%[30, 31] in osteotomies secured with K-wire/tension band technique. Recently, Wei et al. have reported that a total of ten patients (52.6%) underwent removal of implants, which suggested that the rate of reoperation using K-wire in the treatment of comminuted distal humeral coronal shear fracture was greater than when using other internal fixations. Despite most of the studies emphasizing that the K-wire/tension band technique has a high incidence of symptomatic hardware, its specific time of occurrence is not indicated. The internal fixation in all patients in this study was removed within 10 months to one year, which significantly reduced the occurrence of related symptoms. This suggests that the symptoms related to K-wire/tension band technique may occur in the late stage of the operation.
Risk factors for elbow joint stiffness include advanced age, more severe soft tissue or bone injury, delayed surgery, and prolonged immobilization following surgery (over 14 days). All patients underwent necessary rehabilitation exercises in the early postoperative period. Therefore, only one patient (6.7%) in the L-M group developed joint stiffness due to poor compliance, and the range of motion of the elbow was eventually restored after elbow adhesiolysis and active remedial rehabilitation. Superficial infections can be difficult to distinguish from mild wound hematoma or erythema and usually subside with oral antibiotics. They occur in about 20% of patients after ORIF of the distal humerus, commonly after olecranon osteotomy with plate fixation[42, 43]. In the present study, one patient in each of the P-A and L-M groups (7.7% and 6.7%, respectively) had abnormal postoperative wounds that healed after a dressing change and anti-infection treatment.
The present study had several limitations. First, since this was a retrospective study, patient data could not be controlled and the choice of patients was not randomized, creating an unavoidable bias. Second, the present study involved three subtypes (OTA/AO C1, C2, and C3) of distal humeral fractures. Due to the limited sample size, it was not possible to evaluate the clinical efficacy of the two surgical approaches in different subtypes. Third, although the present study emphasized the advantages of the combined anterior and posterior approach in terms of articular surface exposure, no further anatomical study was conducted to determine the exposure range of the specific articular surface. Finally, the clinical efficacy of a combined P-A approach compared to a single posterior approach was not evaluated because a single olecranon osteotomy approach for the treatment of distal humeral fractures was not utilized in this study.