Operative Techniques and Preferences in Anterior Cruciate Ligament (ACL) Reconstruction Surgery: A Cross-Sectional Survey of Filipino Surgeons

Introduction

Anterior cruciate ligament (ACL) tears are common injuries in recreational and competitive sports, often leading to restriction of activities for athletes until full recovery. The ACL is essential for maintaining knee stability during activities that involve rapid change of directions, jumping, landing and twisting motion of the knee.[1] When there is an acute ACL injury, patients typically experience immediate pain on weight bearing, swelling, joint effusion and instability, which will limit their ability to perform daily activities. When acute symptoms have subsided, instability on activities of daily living is the usual symptom that is left. Surgical intervention is frequently required to restore normal anatomic knee function and stability, particularly for active individuals.

The primary goal of ACL reconstruction is to replace the damaged ligament with a graft, thereby reestablishing the stability of the knee joint. Various surgical techniques have been developed over the years (ie, single-bundle and double-bundle reconstructions, all-inside and outside-in technique, button and screw fixation, augmentation techniques, etc.), each with distinct advantages and disadvantages. While single-bundle techniques have been widely adopted due to their relative simplicity and effectiveness, double-bundle techniques are gaining attention for their potential to more closely replicate the native anatomy and function of the ACL.[2]

Despite advancements in surgical techniques and rehabilitation protocols, there remains considerable variability in practice patterns among surgeons. The gold standard for ACL reconstruction has not been established. Multiple studies have tried but failed to consistently show the advantage of one technique over the other. Factors influencing these preferences include surgeon experience, patient demographics, injury severity and institutional resources.[3] In the Philippines, where the incidence of ACL surgery is rising, understanding the preferences of orthopedic surgeons regarding operative techniques is essential for optimizing patient care.

This study aims to explore the current practices of Filipino orthopedic surgeons in treating ACL injuries. By identifying preferred surgical techniques and factors influencing these choices, this research will contribute valuable insights that can inform clinical practice guidelines and enhance training programs for future surgeons.

Objectives

This study aims to determine the current practices of Filipino orthopedic surgeons and their preferences in performing ACL reconstruction surgery.

Specific Objectives

1. To determine the patient selection criteria of Filipino surgeons for ACL reconstruction.
2. To assess the preoperative management including preoperative rehabilitation and timing of surgery.
3. To assess operative techniques including tunnel placement, harvest technique, graft preference, augmentation techniques and fixation device.
4. To assess postoperative rehabilitation protocols such as return to activity timing, weight-bearing status and allowable range of motion.
5. To identify surgeon and patient factors that will influence management.

Significance of the Study

This study aims to explore the current practices of Filipino orthopedic surgeons in treating ACL injuries. By identifying preferred surgical techniques and factors influencing these choices, this research will contribute valuable insights that can inform clinical practice guidelines and enhance training programs for future surgeons.

Study Design

This research is a cross-sectional survey design to gather data on the perioperative techniques and preferences of orthopedic surgeons in the Philippines regarding ACL reconstruction. 

Methodology

Data Collection Procedure

The questionnaire was conducted through Google Form. It was distributed electronically via e-mail or Viber message to members of the POA (Philippine Orthopaedic Association) and POSSM (Philippine Orthopaedic Society for Sports Medicine). The senior author is an officer of the POSSM and recruited participants during their regular face-to-face meetings and conferences. The senior author distributed the survey through the POSSM Viber group. Some of the potential participants were contacted through e-mail obtained from previous correspondence and association with the authors. Follow-up reminders were given before the end of the data collection period to enhance response rates. The survey was completed in 5 to 10 minutes. The latest and most complete response was the one recorded if there were any duplicated responses. The link for the Google Forms was accessible during the data collection period, which was 2 weeks. After which, all collected data was exported to an Excel file into a password protected folder in the principal investigator’s hard drive. The electronic copy of the survey and responses were deleted after data analysis.

Data Collection Tool

A structured questionnaire was developed, consisting of:

• Demographic information (age, years of experience, annual case load).
• Preoperative factors (surgical timing, preoperative rehabilitation)
• Preferred surgical techniques (single-bundle versus double-bundle reconstruction, fixation, anatomical landmarks, augmentation).
• Graft selection (hamstring, patellar tendon, quadriceps tendon).
• Postoperative protocols and rehabilitation practices (weight bearing, brace use, return to activity timing).
• Factors influencing surgical decisions (patient demographics, patient activity level).

Participants

Inclusion Criteria:

1. Licensed orthopedic surgeon from the Philippines
2. Fellow of Philippine Orthopaedic Association (POA) and/or Philippine Orthopaedic Society for Sports Medicine (POSSM)

Exclusion Criteria:

1. Surgeons who were in residency training.

Sample Size

To calculate the sample size for a cross-sectional study with a known population size of N=68 total number of sports surgeons, the investigators used a 95% confidence interval (Z) of 1.96, margin of error (C) of 5% and proportion (p) of 0.5. The investigators used the correction formula to adjust for a finite population. The calculated sample size (S) was 384 and the population used was 68. 

A minimum of 58 participants was targeted based on the result of this computation.

Outcomes

The primary outcomes are surgeon graft preference, reconstruction techniques, preoperative protocols and postoperative protocols.

Data Analysis

Descriptive statistics summarized demographic data and surgical preferences. It was displayed through graphs and figures. Deidentified data was recorded and stored electronically. Comparative and trend analysis was done on the collected data by bivariate crosstabulation.

Study Site

The primary study site was in the University of Santo Tomas Hospital – Orthopedic Learning Center. The data collection was done online, but data analysis and record keeping were at the Orthopedic Learning Center.

Ethical Considerations

The protocol, informed consent forms, and all participant materials were submitted to the UST Hospital – Research Ethics Committee (USTH-REC) for review and approval. Before enrollment of any participants, approval of both the protocol and consent forms was obtained. Amendments to the protocol, as well as consent forms, required review and approval by the USTH-REC before changes were instituted. The study was conducted in conformity with the Declaration of Helsinki, the Good Clinical Practice, and the National Ethical Guidelines for Research Involving Human Participants (NEGRIHP) 2022.

Conflict of Interest and Funding

The senior author is an officer of POSSM and, therefore, was not included in the recruitment process due to the potential of his influence on other respondents. No potential conflicts of interest were identified. There was no sponsorship requested from any pharmaceutical company or organization directly or indirectly related to POSSM, POA, or the investigators. This study was initiated and subsidized fully by the author.

Privacy and Confidentiality

All pieces of information were stored in a secure office. After data collection, all collected data were exported to an Excel file into a password-protected folder in the principal investigator’s hard drive. The electronic copy of the survey and responses was deleted after data analysis. All electronic documents were saved on a secure folder with password access. Only members of the research team were allowed to access the above-mentioned data. All recognizable information and data were assigned a code number to mask the identity of each participant before data analysis. The research records are kept for at least two years following completion of the study, and these records will be disposed of through erasing and reformatting of the hard drive for electronic data.

Recruitment Process

The questionnaire was conducted through Google Forms. After securing approval from the president of the POSSM (Philippine Orthopaedic Society for Sports Medicine), it was distributed electronically via Viber message through the Viber group of the members of the POSSM and POA (Philippine Orthopaedic Association). Also, the principal author presented the protocol and tried to recruit participants during the next meeting and conference of the POSSM. These meetings are regularly attended by members of the POSSM and residents of other training institutions. The electronic informed consent form was placed on the first page of the Google Forms survey. If the participants agreed to the consent, they were then redirected to the survey form. If the participants did not agree, they were redirected to the end page.

Risk and Benefits

The potential risks of the study were inconvenience and the potential breach of confidentiality. To mitigate these risks, the investigators performed the data collection electronically with a 5-10 minute survey. To mitigate the risk of potential breach in confidentiality, the previously mentioned data safety, data deidentification, and data storage and disposal measures were strictly observed.

Although there are no direct benefits to the participants of the study, the indirect benefit of the study is the possible societal benefit. This study might influence and help future surgeons with decision-making based on patient factors.

Compensation and Incentives

This study was initiated and subsidized fully by the author. The participants did not receive any monetary or non-monetary compensation, and all follow-up interactions with the participants were conducted through email or social media (Viber) message if necessary.

Vulnerability

Since the study involved collecting data on professional practices and preferences, there was a risk of breaching participants' privacy if data were not handled securely. Even with anonymization, there was a possibility that sensitive information (such as practice patterns or outcomes) could be traced back to individual surgeons, particularly in a small professional community. To mitigate this risk, the aforementioned data safety protocols were employed.

Investigators

The investigators are licensed physicians by the Professional Regulation Commission and have a valid Good Clinical Practice (GCP) certificate during the study period. The senior investigator is a fellow of POA and POSSM.

Consent

The participants of the study were messaged through email or social media. Each potential participant was provided an electronic consent with full knowledge of the outcome involved. The informed consent, approved by the USTH-REC and in accordance with regulatory guidelines, was fully explained by the investigators, including the study aims, methods, benefits, and risks, and agreed by the participant before enrollment in the study. Potential participants were informed that inclusion is voluntary and that they may withdraw at any time. The participants were given enough time to read the consent and ask any questions. Once the informed consent was agreed, the subjects were given an electronic copy of the document. After answering the survey, their response and the informed consent form were sent to their provided e-mail. Changes to their answers or the informed consent were allowed within the duration of data collection.

Results

Respondents

A total of 68 surgeons have participated in this study. As of time of writing, there are currently 78 active fellows of POSSM and 5 candidates for membership.

Population Demographic

All of the participants were fellowship-trained surgeons and fellows of the POA and 82.4% of them are also fellows of the POSSM. There were 88.2% of participants under 55 years of age (Figure 1) but their years in practice are mostly distributed. There were 32.4% of participants between 10 to 15 years of practice and 26.5% have more than 16 years of practice (Figure 2).

Among them 29.4% does 10 to 25 ACL reconstruction cases a year. Around one-fourth (26.5%) does between 25 to 50 cases. Another fourth does more than 50 cases a year.

Preoperative Protocol

Results of the survey pertaining to preoperative practices showed that more than half of the surgeons (56%) base the timing of surgery on objective measure rather than time from injury (Figure 4).

More surgeons refer their patients to preoperative rehabilitation than not. A significant portion of them depend on patient factors to decide if preoperative therapy will be needed (Figure 5).

Technique Preferences

Almost all (91.2%) of the surgeons prefer hamstring graft for their primary ACL reconstruction cases. The second and third most used grafts are bone-patellar tendon-bone (BPTB) and quadriceps tendon, respectively (Figure 6).

Most (91.2%) of them utilize a single-bundle reconstruction technique. The rest prefer double bundle technique or an individualized approach.

With regards to intraoperative landmarks for tunnel placement, participants can use and select multiple landmarks. Half (52.9%) of the surgeons use the bifurcate ridge as landmark for the femoral tunnel and 26.5% use the lateral intercondylar ridge as the landmark, while 20.6% and 11.8% utilize the anteromedial and posterolateral bundle footprint, respectively. Two surgeons used all landmarks to make the femoral tunnel (Figure 8).

88.2% created a femoral tunnel through the anteromedial portal only, while only two surgeons mainly utilized the transtibial technique and 3% of surgeons used both techniques. Six percent of surgeons used an accessory anteromedial portal to create the femoral tunnel (Figure 9).

For femoral fixation, most (79.4%) of the surgeons fixed the graft using a button, while 14.7% preferred to use interference screw fixation. Four surgeons used either base on their personal criteria (Figure 10).

Like femoral tunnel landmarks, respondents can choose multiple landmarks for tibial tunnel placement. The landmark for placement of the tibial tunnel that was most utilized was the posterior border of the anterior horn of the lateral meniscus at 73.5%, while 26.5% of respondents used the anteromedial bundle footprint. The area anterior to the medial eminence or behind the intermeniscal ligament was utilized as landmark by 17.6% of surgeons, each. Other landmarks used were the posterolateral bundle footprint, area between the eminences and the junction of middle and posterior of the tibial footprint, just lateral to the medial eminence (Figure 11).

The preferred method for tibial tunnel fixation was interference screw fixation at 94.1% while the rest preferred button fixation. No other fixation methods were utilized by the respondents (Figure 12).

During graft fixation, most surgeons (91.2%) flex the knee in 20-30 degrees while 8.8% placed the knee in extension (Figure 13). At the same time, 29.4% placed 40N (Newtons) of posterior drawer force while fixing the graft and the same number of surgeons preferred 20N instead. Surgeons who do not apply force during fixation were 20.6% and surgeons who placed 80N of force were 3%, while another 3% placed the strongest pull they could apply. Ten of the respondents did not measure or were not sure of the applied force (Figure 14). In addition, two of the surgeons also internally rotated the tibia during fixation.

In primary ACL reconstruction in high-risk patients (increased posterior tibial slope, 3+ pivot shift, pivoting sports, Segond fracture, general laxity), surgeons are equally divided on performing augmentation in these patients (Figure 15). Of the surgeons that do augmentation, 40% use synthetic material such as Fibertape as augments, while 30% of respondents performed anterolateral ligament reconstruction or lateral extra-articular tenodesis and 15% of surgeons utilized double fixation methods on both tunnels. Two surgeons performed a double bundle technique and another surgeon considered using a BPTB graft.

For revision ACL reconstruction surgery, 44.1% utilized BPTB as graft while 29.4% used the hamstring tendon; 11.8% used the quadriceps tendon and another 11.8% used the personal tendon as grafts. Three percent of the surgeons did not do revision surgery (Figure 17). It was noted that 38.2% of the surgeons do augmentation in revision surgery while 55.9% do not. Two surgeons perform augmentation if the patient is a high-performance athlete (Figure 18). Of the surgeons that do augmentation in revision surgery, 56.3% perform lateral extra-articular tenodesis, 43.8% perform synthetic material augmentation and 18.8% perform anterolateral ligament reconstruction (Figure 19).

PostOperative Protocols

Immediate weight bearing after an isolated ACL reconstruction was allowed by 94.1% of surgeons. The rest allowed weight bearing after 2 to 4 weeks after the surgery (Figure 20).

Knee flexion was allowed up to 90 degrees immediately after surgery by 52.9%, While 35.3% did not restrict knee flexion and the rest of the respondents allowed 0 to 30 degree of knee flexion (Figure 21).

A knee brace was placed by 64.6% of surgeons after surgery while 32.4% did not and 3% of surgeons placed a brace depending on preoperative muscle strength and performance (Figure 22).

Patients were cleared for jogging at 1 to 2 months, 2 to 3 months, 3 to 4 months, 4 to 5 months and 6 to 8 months by 5.9%, 23.5%, 41.2%, 26.5% and 2.9% of surgeons, respectively (Figure 23).

Clearance for non-contact sports was given at 3 to 4 months, 4 to 5 months, 6 to 8 months and 9 to 11 months by 2.9%, 5.9%, 50% and 29.4% of surgeons, respectively (Figure 24).

Pivoting sports were permitted at 4 to 5 months, 6 to 8 months, 9 to 11 months and 12 or more months by 2.9%, 14.7%, 44.1% and 38.2% of surgeons, respectively (Figure 25). For unrestricted sport participation, 52.9% of surgeons cleared their patients by 12 months or more and 29.4% permitted patients by 9 to 11 months and 17.6% by 6 to 8 months (Figure 26).

Comparative Analysis

After tabulating and visualizing results of the survey, bivariate analysis was conducted using cross tabulation of the results to determine trends. Graphs were made to visualize trends.

The investigators looked if age and years of practice affected the clearance to return to activity. The participants were grouped into four age categories as shown in Figure 27. Although the graph shows that the 25-34 years old group had the earliest return to activity among all groups, there were only two respondents in this group. If we focus on the other three groups, there seems to be a trend that the younger group tends to clear patients earlier than the older age groups (Figure 27). When looking at years of practice, the investigator saw that the 0-5 years’ group cleared patients the earliest in pivoting and unrestricted sports versus the longer groups (Figure 28), which correlates well with the previous figure.

Looking at surgeons that did ACL reconstruction augmentation in high-risk patients, they cleared patients earlier as compared to surgeons that did not augment in high-risk patients (Figure 29).

The investigators also cross-tabulated surgeons that did ACL augmentation in high-risk patients to their age and years of practice. Both graphs showed a consistent trend that younger and newer surgeons preferred to do ACL augmentation in high-risk patients versus older and more experienced surgeons (Figure 30 and 31).

Discussion

The findings of this study offer significant insights into the current practices and preferences of Filipino orthopedic surgeons regarding ACL reconstruction surgery. Key patterns and trends were identified in the choice of surgical techniques, grafts, intraoperative methods and postoperative protocols, with implications for both clinical practice and future research.

Surgical Techniques and Graft Preferences

The overwhelming preference for hamstring tendon grafts (91.2%) and single-bundle reconstruction (91.2%) reflects a trend consistent with literature, particularly in resource-limited settings where cost and accessibility play pivotal roles. Studies such as those by Tang, et.al.[4] highlight similar preferences among Chinese orthopedic surgeons, where single-bundle reconstructions and hamstring autografts are also predominant. In the Philippines, graft choices are limited due to unavailability of allografts for reconstruction. However, the reported preference for hamstring grafts over BPTB grafts contrasts with trends in Western countries where BPTB grafts are more commonly utilized in high-demand and professional athletes.[5] 

Most respondents opted for anteromedial portal femoral tunnel creation with button fixation and interference screw fixation for the tibial tunnel. The button-screw fixation for femoral and tibial tunnel, respectively, was the most commonly preferred method, similar to previous studies in different regions.[4,5] The emphasis on using landmarks such as the bifurcate ridge for tunnel placement aligns with current efforts to replicate native ACL anatomy.[6]

Augmentation

Augmentation techniques were evenly divided among respondents for high-risk patients. Surgeons employing augmentation were predominantly younger and less experienced, suggesting a generational shift towards embracing more complex and innovative methods. This aligns with previous studies, who emphasize the growing interest in augmentation techniques for high-risk patients and revision cases.[5,7] Previous studies have also highlighted the preference of younger surgeons in augmenting ACL reconstruction. Several studies have emphasized the importance of the anterolateral ligament in ACL-deficient knees.[7] 

Postoperative Protocols and Rehabilitation

Postoperative practices among Filipino surgeons reflect a wide variety of protocols. Immediate weight bearing was permitted by 94.1% of respondents, aligning with modern rehabilitation protocols that advocate for early mobilization to prevent stiffness and improve outcomes. However, variability in knee brace usage and restrictions on range of motion suggests differing interpretations of best practices, likely influenced by institutional and patient-specific factors.

The variety in clearance times for different activities (eg, jogging, non-contact sports, pivoting sports) further emphasizes the individualized nature of postoperative management and preferences of surgeons. There are differing opinions on traditional versus accelerated rehabilitation programs.[8] Younger surgeons appeared more inclined to clear patients for earlier return to activity, potentially reflecting greater confidence in advanced techniques and rehabilitation strategies. This may also be due to the trend of younger surgeons that augment ACL reconstruction clear patients earlier for return to activity.

Comparative Trends and Implications

This study’s findings align with international trends while highlighting specific differences influenced by the Philippine healthcare landscape.[5] For instance, financial constraints and resource availability likely contribute to the preference for hamstring grafts and single-bundle techniques. Additionally, the lack of standardized protocols for tunnel placement, fixation methods and rehabilitation highlights the need for clinical guidelines and further clinical trials with long-term outcomes.

The generational differences in augmentation preferences and clearance times also indicate evolving practices that may warrant further investigation. Younger surgeons’ greater willingness to adopt augmentation techniques and permit earlier return to activity suggests potential shifts in training and practice, maybe due to recent literature. These trends could shape future educational programs and clinical guidelines tailored to the Filipino context.

Limitations and Future Directions

While the study provides a comprehensive overview of current practices, it is not without limitations. The reliance on self-reported data introduces potential recall bias, and the sample size, though sufficient for analysis, may not fully represent all Filipino orthopedic surgeons. These preferences do not necessarily translate to the true incidence of the techniques. Future studies could expand the sample size and include qualitative interviews to gain deeper insights into decision-making processes.

Further research should also explore patient outcomes associated with different surgical and postoperative practices to establish evidence-based guidelines. The development of standardized protocols could enhance consistency in care delivery and optimize outcomes for ACL reconstruction patients in the Philippines.

Conclusion

This study provides a detailed analysis of the practices and preferences of Filipino orthopedic surgeons in ACL reconstruction revealing significant trends in surgical and postoperative protocols. The preference for hamstring grafts and single-bundle techniques reflects practical considerations influenced by regional resource constraints and patient demographics. The findings also highlight generational differences in the adoption of advanced techniques, such as augmentation, and variations in postoperative protocols.

Despite its contributions, the study acknowledges limitations such as reliance on self-reported data and a limited sample size. Future research should expand on these findings by incorporating patient outcomes and qualitative insights to develop evidence-based guidelines. Standardizing surgical and rehabilitation protocols tailored to the Filipino context has the potential to enhance care consistency and improve long-term outcomes for ACL reconstruction patients.