Anterior cruciate ligament (ACL) reconstruction is a common surgical procedure aimed at restoring knee stability and function after ACL injury, which predominantly affects athletes involved in high-demand sports. The success of ACL reconstruction is heavily influenced by postoperative rehabilitation, which plays a critical role in ensuring optimal recovery and return to sports or daily activities. Rehabilitation protocols vary widely, incorporating different exercises, intensities, and timelines, making it essential to evaluate their comparative effectiveness.[1][2]

The human knee joint relies on the ACL for stability, especially in dynamic and high-impact sports that involve sudden changes in direction and speed. An ACL injury not only disrupts this stability but also significantly affects an individual's mobility and quality of life. Post-surgery, rehabilitation is crucial for recovery, focusing on reducing swelling, restoring joint motion, improving muscle strength, and ultimately, ensuring functional stability.[3][4]

Recent research has shown that the type and intensity of rehabilitation protocols can significantly influence the outcomes of ACL reconstruction. Protocols range from conservative to accelerated, each with specific exercises, progression criteria, and duration. Conservative approaches often emphasize slower progression to ensure healing of the graft, whereas accelerated protocols encourage quicker restoration of function and return to sports, which can be beneficial for athletes.[5]

A comparative analysis of these protocols is essential to determine which approach offers the best outcomes in terms of pain management, functional recovery, and return to pre-injury activity levels. Furthermore, understanding the impacts of different rehabilitation strategies can help in tailoring individualized rehabilitation plans based on the patient's specific needs, health status, and recovery goals.[6][7]

Aim

To evaluate and compare the effects of different rehabilitation protocols on recovery outcomes after ACL reconstruction surgery.

Objectives

1. To assess the rate of functional recovery in patients following different ACL rehabilitation protocols.
2. To compare the incidence of reinjuries between various rehabilitation approaches post-ACL reconstruction.

Source of Data

The study retrospectively analyzed medical records of patients who underwent ACL reconstruction at our institution.

Study Design

This was a retrospective cohort study that compared different rehabilitation protocols in patients after ACL reconstruction.

Study Location

The research was conducted at the Department of Orthopedics, Tertiary care hospital.

Study Duration

Data were collected from January 2021 to December 2023.

Sample Size

The study included a total of 180 patients who underwent ACL reconstruction during the study period.

Inclusion Criteria

Patients included were those aged 18-50 years, both genders, who underwent primary ACL reconstruction using hamstring tendon autografts or allografts.

Exclusion Criteria

Excluded were patients with previous knee surgeries, multi-ligament injuries, concomitant fractures, or systemic diseases affecting mobility.

Procedure and Methodology

Patients were allocated to one of three rehabilitation protocols based on surgeon preference and patient consent: conservative, moderate, and accelerated. The rehabilitation programs were standardized in terms of exercise types but varied in intensity and progression speed.

Sample Processing

Not applicable, as the study did not involve laboratory processing of biological samples.

Statistical Methods

Data were analyzed using SPSS software. Descriptive statistics summarized patient demographics and outcomes. Comparative analysis was performed using ANOVA for continuous variables and chi-square tests for categorical variables, with p-values less than 0.05 considered statistically significant.

Data Collection

Data were collected from medical records, including demographic details, type of graft used, rehabilitation protocol followed, functional recovery scores (measured by standard physiotherapy assessments), reinjury rates, and patient-reported outcome measures (PROMs).

Table 1: General Outcomes and Characteristics

This table evaluates general characteristics and outcomes across three rehabilitation protocols: Conservative, Moderate, and Accelerated, for patients undergoing ACL reconstruction. Age shows a gradual decrease from Conservative (31.2 years) to Accelerated (28.3 years) groups, but differences are not statistically significant (P=0.073). BMI similarly decreases across the groups from 25.4 in Conservative to 24.2 in Accelerated, but again without significant difference (P=0.157). Notably, the Time to Full Weight Bearing significantly decreases across the groups, with patients in the Accelerated protocol achieving this milestone much quicker (10.6 weeks) than those in the Conservative protocol (14.7 weeks), with a P-value <0.001. Patient Satisfaction Scores also improve significantly with more aggressive rehabilitation, rising from 8.1 in the Conservative group to 8.9 in the Accelerated group (P=0.022).

Table 2: Functional Recovery Scores

Functional recovery following ACL reconstruction is captured at 1, 3, and 6 months post-surgery across the three groups. Initially, at 1 month, there is a marked increase in functional scores from Conservative (68.4) to Accelerated (77.3), with a significant difference (P=0.015). This trend is more pronounced at 3 and 6 months, where scores for the Accelerated group reach 88.2 and 95.8 respectively, significantly higher than those in the Conservative group, which scores 75.1 and 82.9 at the same intervals. The statistical significance of these differences becomes increasingly notable (<0.001), suggesting accelerated protocols may offer superior functional recovery.

Table 3: Incidence of Reinjuries

This table presents the percentage of patients experiencing reinjuries within 6 and 12 months post-surgery, segmented by rehabilitation protocol. The Conservative protocol shows the highest reinjury rates (12.3% and 16.4%, respectively), while the Accelerated protocol demonstrates the lowest (4.9% and 7.6%, respectively). The differences in reinjury rates across the protocols are statistically significant both at 6 months (P=0.048) and 12 months (P=0.033), indicating that more aggressive rehabilitation protocols may be associated with lower reinjury rates.

The findings from Table 1 indicate a significant decrease in the time to full weight bearing as rehabilitation protocols transition from Conservative to Accelerated, with the Accelerated group showing the quickest recovery at 10.6 weeks.

This is consistent with findings from other studies that suggest that accelerated rehabilitation protocols can significantly reduce recovery time without compromising the integrity of the surgical repair Cvjetkovic DD et al.(2015)[8]. Patient satisfaction scores also notably improve in more aggressive rehabilitation settings, echoing the results of a study by Wu J et al.(2022)[9], which found that higher satisfaction in ACL reconstruction patients was associated with faster return to normal function.

The data from Table 2 highlights a significant improvement in functional scores from 1 to 6 months across all groups, with the most pronounced gains observed in the Accelerated protocol. These findings align with those reported by Zaffagnini S et al.(2015)[10], who documented faster and more substantial functional improvements in patients undergoing more intensive rehabilitation programs. These results underscore the efficacy of tailored rehabilitation protocols in enhancing short- and long-term functional recovery post-ACL reconstruction.

In Table 3, the incidence of reinjuries within 6 and 12 months post-surgery decreases as the intensity of the rehabilitation protocol increases. The results suggest that Accelerated protocols, despite their rigorous nature, may not increase the risk of reinjury, which corroborates the findings of Forrester LA et al.(2019)[11] that higher intensity rehabilitation can be safe and effective in reducing the rate of ACL reinjuries. These findings are particularly important for athletes aiming for a faster return to sport, as they suggest that more aggressive rehabilitation might be pursued without an increased risk of reinjury.

The comparative analysis of different rehabilitation protocols following anterior cruciate ligament (ACL) reconstruction has elucidated significant findings that could influence clinical practices and patient outcomes. This study's exploration into conservative, moderate, and accelerated rehabilitation protocols reveals distinct advantages in adopting more accelerated approaches post-ACL reconstruction.

Firstly, the accelerated rehabilitation protocol demonstrated a significantly reduced time to full weight bearing compared to conservative approaches, underscoring the potential for expedited functional recovery without compromising the integrity of the surgical repair. Such findings are instrumental for clinical settings where reducing recovery time is crucial for patient satisfaction and early return to daily activities or competitive sports.

Furthermore, functional recovery scores consistently showed superior improvement in the accelerated protocol group across all time points (1, 3, and 6 months post-surgery). This enhanced recovery trajectory not only supports the patient's desire for a quicker return to pre-injury levels of activity but also suggests that more intensive rehabilitation may contribute to better long-term joint stability and mobility.

Importantly, the study also highlighted a lower incidence of reinjuries in the accelerated protocol group, challenging the traditional concerns that faster-paced rehabilitation could lead to higher reinjury rates. This aspect of the findings suggests that with appropriate oversight and patient adherence, accelerated rehabilitation can be safely implemented without increasing the risk of complications.

In conclusion, this comparative analysis provides robust evidence that supports the implementation of accelerated rehabilitation protocols in ACL reconstruction recovery. By fostering faster recovery times, improving functional outcomes, and maintaining a low risk of reinjuries, accelerated rehabilitation protocols can significantly enhance patient outcomes. Future research should continue to refine these protocols, ensuring they are tailored to individual patient needs and clinical contexts to maximize the benefits of rehabilitation after ACL surgery.

LIMITATIONS OF STUDY

1. Retrospective Design: Being a retrospective study, there are inherent limitations related to the collection and analysis of pre-existing data. This includes potential biases in how data were originally recorded and limitations in the ability to control for all potential confounding variables that could influence outcomes.
2. Sample Size and Distribution: Although the total sample size was adequate (n=180), the distribution among the three groups (conservative, moderate, accelerated) might still not fully represent the general population undergoing ACL reconstruction. Furthermore, the division into three distinct groups assumes equal variance among participants’ baseline characteristics, which might not be the case.
3. Variability in Rehabilitation Protocols: While the study categorized rehabilitation into three protocols, there can be substantial variability within each category regarding the specific exercises, intensity, and progression criteria employed by different therapists or institutions. This variability can affect the generalizability of the results.
4. Subjective Measures: Patient satisfaction and functional recovery scores rely heavily on self-reported measures, which can introduce subjective bias into the study outcomes. Objective measures of knee stability and function, such as imaging or biomechanical assessments, were not included, which might have provided more comprehensive insights into the differences between protocols.
5. Follow-up Duration: The follow-up period may not have been long enough to fully assess long-term outcomes such as the development of osteoarthritis or long-term knee function. Longer follow-up would help determine if the benefits observed with accelerated protocols persist over time.
6. Exclusion and Inclusion Criteria: The strict exclusion and inclusion criteria, while necessary for maintaining study integrity, limit the applicability of the findings to a broader ACL-reconstructed population. For instance, excluding patients with previous knee surgeries or multi-ligament injuries may exclude a significant portion of the clinical population.
7. Lack of Randomization: The lack of randomization in assigning patients to rehabilitation protocols can lead to selection bias, where certain types of patients may be more likely to be placed in one group over another based on undisclosed or unmeasured factors.
8. Unmeasured Confounders: Factors such as patients' pre-injury activity levels, motivation, compliance with rehabilitation, and access to physical therapy resources could significantly influence outcomes but were not controlled for in this study.

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