Medial knee pain with varus alignment is common in active adults and is associated with increased medial joint loading, cartilage loss, and progression of knee osteoarthritis. Conventional rehabilitation typically emphasizes quadriceps strengthening and general physiotherapy, which may reduce pain and improve function but often has limited effect on abnormal frontal-plane loading and alignment in individuals with varus deformity. Targeted neuromuscular and alignment-focused exercise programs that emphasize hip and lower-limb muscle control may better address underlying biomechanical contributors to medial knee loading.

This randomized controlled trial will compare a traditional/conventional physical therapy program with a specific, alignment-focused exercise program in active adults aged 30-55 years who have medial knee pain, mild to moderate varus deformity, and Kellgren-Lawrence grade 1-3 knee osteoarthritis. Approximately 80 participants will be recruited from an outpatient setting and randomized (1:1) to receive either traditional rehabilitation or a targeted exercise protocol focusing on hip adductors and internal rotators. The supervised intervention will last 6 weeks, with follow-up assessments at 12 weeks, 6 months, and 1 year. The primary outcome is the Oxford Knee Score, with secondary outcomes including lower-extremity function, pain, quality of life, muscle strength, and radiographic alignment.

Medial knee pain in adults with varus lower-limb alignment is a frequent presentation in orthopedic and physical therapy practice. Varus malalignment increases the medial knee adduction moment and concentrates load in the medial compartment, which is associated with greater cartilage loss, radiographic progression of knee osteoarthritis, and faster functional decline compared with neutral alignment. Prospective work has shown that higher dynamic medial knee load predicts greater medial cartilage loss over time in individuals with medial knee osteoarthritis. Conventional conservative management typically focuses on quadriceps strengthening, general lower-limb exercise, manual therapy, and activity modification. Although these approaches often reduce pain and improve function, they may not adequately address the underlying biomechanical factors related to varus alignment and medial loading.

Targeted neuromuscular and alignment-focused exercise interventions have been proposed as a way to optimize frontal-plane control and dynamic alignment of the lower limb. These programs place greater emphasis on hip adductors, abductors, and internal rotators, as well as neuromuscular training during functional tasks (e.g., squatting, stepping, and gait retraining). By improving the strength and coordination of muscles that control pelvic and femoral position, such protocols may help reduce excessive medial knee loading and improve overall joint mechanics during daily and sports activities. Previous studies in knee osteoarthritis and lower-limb malalignment populations suggest that well-designed exercise programs can yield clinically meaningful improvements in pain, function, and, in some cases, measures of alignment or dynamic loading. However, high-quality randomized controlled trials that directly compare a conventional physiotherapy program with a clearly defined, alignment-focused exercise protocol in adults with medial knee pain and varus deformity remain limited.

This trial is designed as a parallel-group randomized controlled study conducted in an outpatient setting. Active adults between 30 and 55 years of age with medial knee pain, mild to moderate varus deformity on long-leg radiographs, and radiographic knee osteoarthritis graded 1-3 on the Kellgren-Lawrence scale are eligible for inclusion, provided they meet predefined anthropometric and health-status criteria and have no significant comorbid musculoskeletal or neurological conditions affecting the lower limb. The target sample size is based on an a priori power analysis to detect a moderate effect size in repeated-measures comparisons between two groups across multiple time points, with allowance for attrition to reach an enrollment goal of approximately 80 participants.

Following baseline assessment, participants will be randomly assigned in a 1:1 ratio to one of two intervention arms using a computer-generated randomization schedule with allocation concealment. The control group will receive a conventional physical therapy program consistent with usual care for medial knee pain and early medial-compartment osteoarthritis. This program typically includes quadriceps and general lower-extremity strengthening, range-of-motion and flexibility exercises, manual therapy and modalities as deemed appropriate by the treating therapist, and functional training (e.g., gait and basic task practice). Exercise dosage and progression will follow standardized guidelines, while still allowing therapists to make minor individual adjustments within the protocol framework.

The experimental group will receive a targeted exercise program that retains core elements of evidence-based knee rehabilitation but places specific emphasis on restoring dynamic alignment and frontal-plane control. The program focuses on strengthening hip adductors and internal rotators, as well as other key hip and lower-limb muscle groups that influence knee valgus-varus mechanics during weight-bearing activities. Exercises include a combination of open- and closed-chain strengthening, neuromuscular control drills, and functional retraining tasks that challenge alignment under progressively increasing load and complexity. The intervention is structured into a 6-week, clinic-based program with supervised sessions, complemented by a structured home exercise component to reinforce gains between visits.

All participants, regardless of group assignment, will undergo standardized outcome assessments at baseline, immediately after the 6-week intervention period, and at medium-term follow-up points (e.g., 3 and 6 months), with an extended follow-up to 12 months for recording clinical relapses or significant symptom flare-ups that require further treatment. The primary outcome is change in knee-specific pain and function as measured by the Oxford Knee Score, a validated patient-reported outcome measure commonly used in knee osteoarthritis and post-surgical populations. Secondary outcomes include lower-extremity function (e.g., Lower Extremity Functional Scale), pain intensity using a numeric rating scale, health-related quality of life (e.g., SF-36), and objective measures of hip muscle strength obtained with manual muscle testing or a handheld dynamometer, depending on the final protocol specifications. Radiographic measures of mechanical alignment, including Hip-Knee-Ankle angle and segmental angles such as the Mechanical Lateral Distal Femoral Angle and Medial Proximal Tibial Angle, will be derived from standardized long-leg standing radiographs and interpreted by a qualified radiologist who is blinded to group allocation.

To minimize measurement bias, outcome assessments will be performed by trained assessors who are not involved in intervention delivery and who remain blinded to treatment assignment. The primary analysis will follow the intention-to-treat principle, comparing changes in the primary and secondary outcomes between the two groups over time using appropriate repeated-measures statistical models. Additional per-protocol or sensitivity analyses may be conducted to explore the robustness of the findings. By directly comparing a conventional physiotherapy program with a clearly specified, alignment-focused exercise protocol in a well-defined subset of adults with medial knee pain and varus deformity, this trial aims to clarify whether targeted exercises confer superior benefits in pain relief, functional improvement, muscle performance, and alignment, and to inform more precise conservative management strategies that may delay or reduce the need for surgical realignment procedures in this population.

• Inclusion Criteria

  • Age 30-55 years
  • BMI 18-25 kg/m²
  • Presence of medial knee pain
  • Mild to moderate varus deformity confirmed via long-leg X-ray (e.g., 2° < Hip-Knee-Ankle angle ≤ 10°)
  • Kellgren-Lawrence grade 1-3 knee osteoarthritis
  • Active adults based on REFA work classification
  • Able and willing to complete a 6-week exercise program and follow-up visits
  • Provision of written informed consent

• Exclusion Criteria:

  • BMI > 25 kg/m²
  • History of knee surgery on the affected side
  • Any contraindication to exercise (e.g., unstable cardiovascular conditions)
  • Other significant musculoskeletal or neurological conditions affecting lower-extremity function (e.g., hip osteoarthritis, rheumatoid arthritis, peripheral neuropathy)