Osteoarthritis (OA) is the most common degenerative joint disease, affecting millions worldwide, particularly in aging populations. It is characterized by progressive cartilage degradation, synovial inflammation, and subchondral bone changes, leading to pain, stiffness, and functional limitations (1). Knee OA significantly impacts mobility and quality of life, with early-stage disease

often managed conservatively through physical therapy, weight management, and pharmacological interventions. However, when these measures fail to provide adequate relief, surgical options such as arthroscopic debridement (AD) and unicompartmental knee arthroplasty (UKA) are considered (2).

Arthroscopic debridement involves removing loose cartilage, smoothing rough joint surfaces, and addressing meniscal tears or synovitis to reduce symptoms and improve function. Although it is a minimally invasive procedure, its long-term efficacy remains debated, with some studies reporting only temporary symptom relief (3,4). In contrast, unicompartmental knee arthroplasty (UKA) is a partial knee replacement targeting a single affected compartment, preserving native joint structures while improving joint mechanics and pain outcomes (5). Recent advancements in arthroscopic-assisted UKA (AA-UKA) have enhanced precision in implant placement and minimized surgical trauma, potentially improving patient outcomes (6).

Despite these surgical advancements, the optimal approach for managing early-stage knee OA remains uncertain. Arthroscopic debridement is widely performed but may not provide sustained benefits, while UKA offers a more definitive solution but comes with higher surgical demands and risks. This study aims to compare the clinical and functional outcomes of AD and AA-UKA in patients with early knee OA, providing evidence to guide surgical decision-making.

Study Design and Participants

This prospective, randomized controlled study was conducted to compare the clinical and functional outcomes of arthroscopic debridement (AD) and arthroscopic-assisted unicompartmental knee arthroplasty (AA-UKA) in patients with early-stage knee osteoarthritis (OA). The study included 100 patients diagnosed with early knee OA (Kellgren-Lawrence grade II-III) based on radiographic and clinical criteria. Patients were randomly assigned into two groups: Group A (n=50) underwent arthroscopic debridement, while Group B (n=50) received arthroscopic-assisted unicompartmental knee arthroplasty.

Inclusion and Exclusion Criteria

Inclusion criteria:

• Patients aged 40–65 years with unilateral knee OA (Kellgren-Lawrence grade II-III).
• Persistent knee pain despite conservative treatment for at least six months.
• Isolated medial or lateral compartment involvement confirmed via radiographic evaluation.

Exclusion criteria:

• Presence of inflammatory arthritis or systemic joint diseases.
• Advanced OA (Kellgren-Lawrence grade IV).
• Previous knee surgery or history of significant knee trauma.
• Severe obesity (BMI >35 kg/m²).

Surgical Procedures

All procedures were performed by experienced orthopedic surgeons using standardized techniques.

Arthroscopic Debridement (AD):

Patients in Group A underwent AD, which involved lavage of the joint, removal of loose cartilage fragments, meniscal trimming (if necessary), and synovectomy when indicated. The procedure aimed to improve joint function by reducing mechanical irritation.

Arthroscopic-Assisted Unicompartmental Knee Arthroplasty (AA-UKA):

Patients in Group B underwent AA-UKA, where arthroscopy was utilized for accurate cartilage assessment and precise implant placement. A minimally invasive approach was used to resurface the affected compartment with a prosthesis while preserving native knee structures.

Outcome Measures

Clinical and functional outcomes were assessed at baseline, 6 months, and 12 months postoperatively using:

• Knee Injury and Osteoarthritis Outcome Score (KOOS): Evaluating pain, symptoms, function, and quality of life.
• Visual Analog Scale (VAS) for Pain: Measuring pain intensity on a 10-point scale.
• Range of Motion (ROM): Assessed using a goniometer.
• Patient Satisfaction: Determined using a standardized questionnaire.

 Statistical Analysis

Data were analyzed using SPSS software (version 26.0). Continuous variables were expressed as mean ± standard deviation and compared using the independent t-test. Categorical data were analyzed using the chi-square test. A p-value of <0.05 was considered statistically significant.

A total of 100 patients were included in the study, with 50 in the arthroscopic debridement (AD) group and 50 in the arthroscopic-assisted unicompartmental knee arthroplasty (AA-UKA) group. Clinical and functional outcomes were assessed at baseline, 6 months, and 12 months postoperatively.

KOOS Score Comparison

The Knee Injury and Osteoarthritis Outcome Score (KOOS) showed a significant improvement in both groups over time. However, the AA-UKA group demonstrated a greater increase in KOOS scores compared to the AD group at both 6 and 12 months. At the final follow-up, the KOOS score in the AA-UKA group was significantly higher (p<0.001) (Table 1).

Pain Reduction (VAS Score)

Both groups exhibited a reduction in pain levels, as measured by the Visual Analog Scale (VAS). The AA-UKA group experienced a more substantial decrease in pain at both 6 and 12 months postoperatively, with a final VAS score of 2.1 ± 0.9 compared to 4.8 ± 1.3 in the AD group (p<0.001) (Table 2).

Range of Motion (ROM) Improvement

The range of motion (ROM) increased in both groups postoperatively, but the AA-UKA group exhibited a significantly greater improvement. At 12 months, the mean ROM in the AA-UKA group was 134° ± 4°, while it was 122° ± 5° in the AD group (p<0.001) (Table 3).

These results indicate that while both procedures provide symptomatic relief, AA-UKA leads to superior functional outcomes, pain reduction, and patient satisfaction compared to arthroscopic debridement. ​​

Table 1: KOOS Score Comparison

Table 2: Pain Reduction (VAS Score)

 Table 3: Range of Motion (ROM) Improvement

The management of early-stage knee osteoarthritis (OA) remains a challenge, with surgical options such as arthroscopic debridement (AD) and arthroscopic-assisted unicompartmental knee arthroplasty (AA-UKA) being widely used. The present study aimed to compare the clinical and functional outcomes of these two procedures, demonstrating that AA-UKA offers superior pain relief, range of motion (ROM), and patient satisfaction compared to AD.

Arthroscopic debridement is commonly performed in patients with early knee OA to remove loose cartilage fragments and improve joint function. However, its effectiveness remains controversial, with some studies reporting only short-term pain relief and limited long-term benefits (1,2). The present study found that while AD led to a moderate reduction in pain and an improvement in KOOS scores, the results were significantly inferior to those seen with AA-UKA at 6 and 12 months. These findings align with previous research suggesting that AD does not alter the progression of OA and may not provide sustained symptom relief in many cases (3,4).

In contrast, AA-UKA has gained popularity due to its ability to preserve native knee structures while replacing the damaged compartment. Studies have reported that UKA provides better functional outcomes and faster recovery compared to total knee arthroplasty (5,6). The current study found that KOOS scores in the AA-UKA group improved significantly from baseline to the 12-month follow-up (p<0.001), supporting the notion that UKA is a more effective option for isolated compartmental OA (7,8). The significant reduction in VAS pain scores in the AA-UKA group further reinforces its advantages over AD, as similar trends have been reported in previous clinical trials (9,10).

Range of motion (ROM) is an essential factor in postoperative recovery, influencing overall function and quality of life. The results showed that ROM improved significantly in the AA-UKA group compared to the AD group (p<0.001), consistent with prior findings that UKA facilitates better joint mechanics and movement preservation (11,12). Moreover, patient satisfaction was markedly higher in the AA-UKA group (92%) compared to the AD group (68%), which is in agreement with earlier studies demonstrating greater satisfaction rates following UKA (13).

Although AA-UKA showed superior outcomes, it is important to consider potential risks and limitations. UKA has been associated with complications such as polyethylene wear, implant loosening, and the need for revision surgery in some cases (14). However, advancements in surgical techniques, including the use of robotic and arthroscopic-assisted methods, have improved implant accuracy and longevity (15).

The study has some limitations, including a relatively short follow-up period of 12 months and a limited sample size. Future studies with long-term follow-ups and larger cohorts are required to validate these findings further. Despite these limitations, the results strongly suggest that AA-UKA is a more effective surgical option than AD for patients with early-stage knee OA, providing better pain relief, functional outcomes, and overall satisfaction.

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