[Abstract] OBJECTIVE: To investigate the efficacy of using Y-shaped plate internal fixation to treat humeral condylar fractures. METHODS: The 12 cases of humeral condylar fracture were treated with Y-shaped plate internal fixation according to AO\ASIF classification: 0 cases of A3 type, 2 cases of C1 type, 4 cases of C2 type and 6 cases of C3 type. Results: 11-30 months follow-up, 6 cases were excellent, 4 cases were good, and 2 cases were acceptable according to the modified Cassebaum evaluation, with an excellent rate of 88%.
Humeral condylar fracture is a fracture of the distal humerus within 2CM above the inner and outer condyles. It is a common fracture. It occurs mostly in young adults, often due to high-energy injuries, and is more difficult to deal with, especially C2-C3 intercondylar humeral fractures are more difficult to reset. In recent years, with the development of orthopedic technology and the constant update of internal fixation materials, surgical treatment of humeral condylar fractures has gradually become a trend. The author has applied Y-shaped titanium plate to treat 12 cases of intercondylar fractures of the humerus since 2005 and achieved satisfactory treatment results.
1 Clinical data
1.1 General information
There were 12 cases in this group, 7 males and 5 females, aged 19-45 years old, average 34 years old, 3 cases were open and the rest were closed fractures. Causes of injury: 7 cases of car accident injury. There were 5 cases of fall injury and 8 cases of combined ulnar nerve injury. All of them were treated surgically within 8~48 hours after the injury. The fractures were classified according to the AO\ASIF classification [1], with 2 cases of C1 type, 4 cases of C2 type and 6 cases of C3 type.
1.2 Surgical method
Brachial plexus or general anesthesia, lateral recumbency, affected limb on top, taking a longitudinal incision at the back of the elbow, and an “S”-shaped incision at the hawk’s beak, cutting the skin, subcutaneous tissue and fascia, freeing the flap to the medial and lateral epicondyles on both sides, finding the ulnar nerve between the ulnar carpal flexors, freeing and protecting the ulnar nerve with a rubber membrane, and then exposing the fracture, in 3 cases In 9 cases, the fracture was revealed by using the ulnar hawk’s-jaw osteotomy approach. For C1 fractures, the fracture was dissected and repositioned, temporarily fixed with a Kirschner pin, and then fixed with a Y-plate. For intercondylar fractures, the medial and lateral condyles were firstly repositioned and fixed with Kirschner pins to change the intercondylar fracture into a supracondylar fracture, and then the crest of the medial and lateral condyles were repositioned with the upper part of the condyle and temporarily fixed with Kirschner pins; the free displaced small bone pieces were repositioned or filled in the bone defect, and attention was paid to maintain the normal lifting angle of about 10 degrees and the anterior inclination angle of 45 degrees, and for C3 type, attention was paid to maintain the width of the humeral carriage, and the fracture was repositioned anatomically as far as possible. After good alignment, a 5CM hollow tension screw or 4MM cancellous bone screw was screwed into the condyle from outside to inside, and then the “Y” shaped plate was attached upside down to the dorsal side of the distal humerus; the epiphysis and the medial and lateral condyles of the humerus were fixed, the kerf pins were removed as appropriate, and the ulnar nerve was returned to its original position or anteriorly (all 8 cases of ulnar nerve injury were explored and moved forward). The skin was drained by placing rubber sheets and suturing all layers of the skin.
1.3 Postoperative management
Drainage was placed for 24 hours, and postoperative muscle contraction activities of clenched fist and extended finger were started immediately after surgery, and gentle active and passive activities were performed.
1.4 Results
All patients in this group were followed up for 2-10 months, with an average of 6 months, and all fractures healed without complications such as ossifying myositis, delayed ulnar neuritis, or failure of internal fixation, according to the modified Cassebaum scoring system (excellent: 15 degrees of elbow extension; 130 degrees of elbow flexion, no symptoms in the elbow joint; good: 30 degrees of elbow extension; 120 degrees of elbow flexion, or subjective symptoms in the elbow joint; may: 40 degrees of elbow extension, and (flexion of the elbow 90-120 degrees, elbow joint with symptoms; poor: extension of the elbow 40 degrees, flexion of the elbow <90 degrees). Efficacy: 10 cases, good 1 case, 1 case, poor 0 cases, excellent rate of 96%, satisfactory results.
2 Discussion
2.1 The necessity of surgery and the choice of timing
The bone quality of the coronal surface of the distal humerus is thin, and there are coronal fossa and hawk’s nest in the front and back respectively, so the fracture in this area is heavily comminuted and difficult to treat; especially the intercondylar comminuted fracture, due to the different sizes of the broken bone pieces, there is often rotation and separation displacement, which is more difficult to treat; if the repositioning and fixation are poor, the structure and function of the elbow joint will be seriously affected in the later stage, only to restore the integrity of the articular surface of the distal humerus and reconstruct the inner and outer lateral columns Only by restoring the integrity of the distal humeral articular surface and reconstructing the equilateral triangle formed by the internal and external columns and the talus can the inherent stability of the joint be restored and the conditions for functional recovery be created. Surgical repositioning and strong fixation are required to meet the need for early postoperative functional exercise, to maximize the restoration of elbow function, and to reduce the disability rate [2]. The earlier the surgery is performed, the better, and the surgery should be performed within 6-8 hours as far as possible to avoid swelling of the affected limb and even blister formation to delay the timing of surgery.
2.2 Selection of surgical approach
The “tongue” flap of the triceps brachii muscle can be opened to reveal the triceps brachii muscle, but it can avoid the osteotomy of the hawk’s jaw, but the damage to the triceps brachii muscle is great and it is not sufficiently revealed, so it is difficult to reset correctly and fix reliably, and the braking time is long, which is not conducive to early joint movement. The ulnar hawkeye osteotomy approach has adequate exposure of the distal humerus and is conducive to the direct visualization of the comminuted fracture for revision and fixation. Due to the specific osteotomy and fixation method, the fixation strength is higher than the tendon suture tension, which can withstand the early activities of the joint, prevent joint stiffness, and facilitate the recovery of joint function. Therefore, the author believes that the hawk’s-eye osteotomy approach is the ideal approach for internal fixation of intercondylar fractures of the humerus.
2.3 Selection of internal fixation materials
There are many methods of internal fixation for intercondylar fractures of the humerus, and the commonly used internal fixation materials include Kirschner pins, tension band tension screws, and double plates [3]. The traditional Kirschner pin fixation suffers from poor fixation, pin wandering, poor stability, inability to perform early functional exercises after surgery, and later leads to complications such as arthrofibrosis and joint ankylosis, which limits the function of the elbow joint [4]. A single tension screw is difficult to fix the supracondylar fracture and has poor stability; AO double plate places a reconstructed plate and 1/3 tubular plate on the lateral and medial side respectively, which reveals more to the medial condyle, causes heavy injury, and is easy to damage the ulnar nerve, and the double plate screws are prone to “fighting” phenomenon. The authors used a Y-shaped plate to treat humeral condylar fractures, which avoids the above-mentioned shortcomings and provides a posterior approach with easy plate placement, significantly shortens the operation time, reduces soft tissue injury, and facilitates the recovery of elbow function. The titanium alloy plate is biocompatible, can be shaped freely, adapts to the morphology of the distal humerus, and adheres well; the symmetrical design of the Y-shaped plate facilitates uniform stress distribution in the medial condyle of the humerus, has strong torsional resistance, and the plate hole distance is small, so more screws can be placed in the epiphysis than the AO double plate. In the posterior extension experiment, the Y-shaped plate and the lateral plate were slightly worse than the medial and lateral double plates, but the difference was not significant; in the torsional resistance experiment, the Y-shaped plate and the medial and lateral double plates were significantly better than the lateral plate, and the Y-shaped plate was slightly better than the double plates. Therefore, Y-shaped plate fixation of the supracondylar humerus and intercondylar fracture can provide enough stability to fix the intercondylar and supracondylar to the humeral stem as a whole and play the effect of strong fixation. Thus, functional impairment of the elbow joint can be performed early to facilitate early recovery of its function.
2.4 Precautions
Attention should be paid to the protection of the ulnar nerve during surgical exposure, and the ulnar nerve should be placed back or moved forward according to the situation between the plate and the nerve after the surgery is completed to avoid ulnar neuritis. Anyone with symptoms of ulnar nerve injury before surgery and contusion of the ulnar nerve on intraoperative exploration should move the ulnar nerve forward after surgery to facilitate ulnar nerve recovery. In our group, two cases of ulnar nerve injury were routinely anteriorized after surgery, and both recovered within 3 months. During surgery, attention should be paid to restoring the anteversion and carry angle of the lower humerus, maintaining the width of the humeral talus, especially for C3 fractures, removing the small intra-articular bones that affect fixation, using autologous iliac bone blocks to fill in the remaining defects, and using the width of the ulnar talus notch to indirectly measure the repositioning of the humeral talus, and operating gently to minimize the stripping of soft tissues to avoid the formation of fibrosis around the joint at a later stage, resulting in Elbow contracture. Early functional exercise should be appropriate and can be based on active activities, supplemented by passive activities, with flexion of the elbow as the main focus and extension of the elbow as a supplement, taking into account the policy of forearm rotation. Forced extension and flexion and forceful activities can cause bleeding and fibrosis, increase the irritation of the joint, and restrict the joint movement.