Methods and study designs
This prospective cohort study was conducted between April 2017 and March 2018 at the Knee Clinics of Be'sat Hospital and the affiliated knee clinic at Hamadan University of Medical Sciences and Health Services (UMSHA). The study focused on patients with intraoperative MCL injury during TKA and examined repair and augmentation methods with initial pull-out or augmentation.
In this study, 553 patients with severe advanced knee arthritis were recruited for knee treatment with TKA. only 13 patients experienced MCL injuries during surgery.
Eligible Criteria
Due to the limited availability of qualified samples, 13 eligible patients with severe knee arthritis who experienced MCL injuries during TKA were included via a census method and subjected to investigation.
Exclusion criteria included patients requiring revision surgery, those with MCL inefficiency identified during preoperative assessments (e.g., severe valgus), individuals undergoing specific systems such as Legacy Constrained Condylar Knee (LCCK) (14) and Rotating Hinged Knee (RHK) (15), and those lacking accessibility for early and late surgical complication follow-up.
Pre-surgery evaluation of the patients
Initially, patients with complaints of knee pain and arthritis visited the hospital's orthopedic clinic and were examined by an orthopedic surgeon and a knee fellowship-trained specialist. They were evaluated based on predefined criteria and enrolled in the study as candidates for TKA.
Preoperative stages included conducting radiographic examinations such as anteroposterior, lateral, patella, and skyline views, performing routine laboratory tests including complete blood count, electrolyte assessment, urinalysis, and, if indicated, coagulation tests and blood glucose level assessment, as well as necessary consultations such as cardiology, internal medicine, anesthesia, etc., depending on the patient's condition, which was carried out for all patients.
For data collection, a questionnaire was used containing information such as age, gender, type of MCL injury, and the technique used for ligament repair or reconstruction. Information regarding the latter two was extracted based on intraoperative events recorded in the surgical report of the patient's file and documented in the questionnaire.
The subjective International Knee Documentation Committee (IKDC) questionnaire (16) was used to evaluate knee pain and function in patients before and after surgery. The IKDC is a patient-completed questionnaire comprising seven items related to knee symptom assessment, two items for knee functional evaluation, and two for assessing the level of sports activities. Scores range from 0 points (highest level of symptoms or lowest level of function) to 100 points (lowest level of symptoms and highest level of function) (17, 18).
Patients received anesthesia in the operating room and underwent knee arthroscopy in sterile conditions with tourniquet control. The classic midline incision was made. Limited bone cuts were made following synovectomy, and ligament balancing was performed. The PCLS prosthesis (19, 20) prosthesis from the Zimmer NexGen or PFC SIGMA DePuy cemented system was used for all patients. Any unintended events, including MCL injury, were recorded.
Intraoperative MCL injuries were classified into two groups and treated. First, Ligament laxity from the femoral or tibial side was re-fixed to its anatomical location on the same bone using the pullout method with Ethibond 5 sutures. second, if partial, injuries at the ligament mid-substance were initially repaired with Ethibond 2 sutures, and if complete, primary repair with augmentation of the semitendinosus tendon was performed.
If intraoperative instability was observed on the medial side after ligament repair or reconstruction using the methods above, the prosthesis type was changed to an LCCK (Low Contact Stress) prosthesis with increased constraint to achieve stability on the medial side. Once stability on the medial side was confirmed throughout the full knee range of motion (RoM) and ligament balancing was completed, the capsule and skin were repaired.
Post-surgery follow-up of the patients
After the surgery, the patients followed a partial weight-bearing (PWB) protocol starting the day after the surgery (21, 22). They were given knee braces to wear for six weeks after the operation. The knee brace was locked in full extension for the first two weeks. At the end of the second week, physiotherapy started (23). During physiotherapy, the patients' knees increased by 30 degrees of motion per week until a full range of motion was achieved by the end of six weeks. At the end of six weeks, stress radiographs, including anteroposterior, lateral, and varus-valgus views, were performed. The knee brace was discontinued if examinations indicated sufficient stability on the medial side. Patients were then followed up at intervals of 3 months, six months, and one year, and at the end of one year, IKDC questionnaires were completed again. The data obtained from clinical examinations, current status descriptions, and paraclinical findings in the researcher-designed checklist were collected and subjected to statistical analysis.
All study participants were provided with necessary explanations and sufficiently informed about the research procedures. Patients entered the study voluntarily, with full awareness and consent. All data obtained from the study participants, whether through questionnaires or examinations, will remain confidential. Patients' names and surnames will not be included in the research under any circumstances; only a unique identification code was used for data analysis. Participants were assured that their decision to participate or withdraw from the study at any time would not disrupt their care and treatment process.
All patients gave written and informed consent to participate in the study, which was approved by the ethics committee of Hamadan University of Medical Sciences (IR.umsha.rec.1399.616).
The collected data were analyzed using SPSS version 21 software. Descriptive statistical indices such as percentages, frequencies, means, and standard deviations were employed to describe the data. The analytical section used a paired t-test to compare patients' mean IKDC scores before and after arthroplasty. The Pearson correlation coefficient was also used to examine the relationship between injury and gender. Furthermore, the Pearson correlation coefficient was employed to determine the correlation between the IKDC score and age. A significance level of 0.05 was considered for all analyses.