Proprioceptive Training for Gait and Knee Function After Anterior Cruciate Ligament Reconstruction

The Effect of Proprioceptive Training on Gait Performance and Knee Function in Patients With Anterior Cruciate Ligament Reconstruction

Anterior cruciate ligament reconstruction (ACLR) is commonly performed to restore knee stability after injury, but many patients continue to experience gait abnormalities and reduced knee function during rehabilitation. Proprioceptive training is frequently included in rehabilitation programs to improve joint position sense, neuromuscular control, and movement coordination, yet its specific effects on gait performance and knee function after ACLR are not fully understood.

This study aims to investigate the effects of a 12-week proprioceptive training program on gait performance and knee function in patients who have undergone ACLR. Patients who meet the inclusion criteria will undergo baseline assessments, including gait analysis and knee function tests. They will then participate in a structured 12-week proprioceptive training program as part of their rehabilitation, followed by post-intervention assessments using the same measures.

The primary outcomes include changes in gait performance, such as walking speed, step length, cadence, support time, knee motion, and knee joint angles and moments during walking. Secondary outcomes include changes in knee function, including isokinetic muscle strength, joint position sense, and patient-reported outcomes measured by the Lysholm score and the International Knee Documentation Committee (IKDC) questionnaire. The findings from this study may help to clarify the functional benefits of proprioceptive training and support the development of more targeted and effective rehabilitation strategies for patients recovering from Anterior cruciate ligament (ACL) injuries.

Anterior cruciate ligament reconstruction (ACLR) is widely performed to restore knee stability after injury; however, many patients continue to experience altered gait patterns, reduced neuromuscular control, and functional limitations during rehabilitation. Proprioceptive deficits after Anterior cruciate ligament (ACL) injury and surgery can contribute to impaired movement coordination and knee joint instability, highlighting the importance of proprioceptive training as part of the rehabilitation process.

This study aims to examine the effects of a structured 12-week proprioceptive training program on gait performance and knee function in individuals following ACLR. Participants who meet the eligibility criteria will undergo baseline assessments that include gait analysis, knee range of motion, muscle strength evaluation, joint position sense testing, and patient-reported functional outcomes. After baseline testing, participants will be assigned to one of two groups. The control group will receive a standard rehabilitation program, while the proprioceptive training group will receive the same standard rehabilitation combined with an additional proprioceptive training program.

The standard rehabilitation program is adapted from the Massachusetts General Brigham Sports Medicine ACLR Rehabilitation Protocol, with minor modifications to accommodate available equipment and safety considerations. The 12-week rehabilitation process is divided into four progressive phases (Phase I: 0-2 weeks, Phase II: 3-5 weeks, Phase III: 6-8 weeks, and Phase IV: 9-12 weeks), focusing on graft protection, restoration of knee range of motion, quadriceps activation, and gradual strengthening and functional progression.

The proprioceptive training protocol is adapted from previously validated progressive exercise programs that use unstable surfaces such as Swiss balls and BOSU balls to improve gait performance and knee joint function. Participants in the proprioceptive training group will train three times per week for a total of 12 weeks. The progression of exercises follows three phases (initial: weeks 1-5, intermediate: weeks 5-8, and advanced: weeks 8-12) and includes balance, coordination, and neuromuscular control activities. All sessions are supervised by a physiotherapist, and progression to the next level is allowed only when balance control is stable and exercises can be performed without pain or adverse symptoms.

The primary outcomes of this study focus on gait performance, including measures such as walking speed, step length, cadence, support time, and knee peak flexion and extension angles and moments, as well as knee range of motion during walking. Secondary outcomes include changes in knee function, such as isokinetic muscle strength, joint position sense accuracy, and patient-reported scores using the Lysholm and International Knee Documentation Committee (IKDC) questionnaires.

The results of this study may provide a better understanding of the role of proprioceptive training in improving functional recovery after ACLR. By identifying its effects on gait mechanics and knee function beyond standard rehabilitation alone, this research may support the development of more targeted and effective rehabilitation strategies for individuals recovering from ACL injuries.

Inclusion Criteria:

• Adults aged 18-40 years who have undergone primary unilateral anterior cruciate ligament reconstruction (ACLR) using an autograft.
• At least 3 weeks postoperatively and currently engaged in the early-stage rehabilitation phase following ACLR.
• Demonstrate near-full passive knee extension (≤ 5° loss) and at least 90° of passive knee flexion in the operated limb.
• Able to walk independently without assistive devices and perform basic functional tasks (e.g., normal walking, single-leg stance).
• No prior surgery or major injury to the contralateral knee or other lower limb joints.
• No neurological, vestibular, or systemic conditions affecting proprioception, motor control, or physical performance.
• Not currently participating in any structured proprioceptive or neuromuscular training programs.
• Willing and able to comply with the intervention protocol and follow-up, and able to provide written informed consent.

Exclusion Criteria:

• History of revision anterior cruciate ligament surgery, bilateral ACLR, or concurrent reconstruction of other knee ligaments (e.g., posterior cruciate ligament, medial collateral ligament, lateral collateral ligament) in the affected knee.
• Meniscal repair or other intra-articular procedures that restrict knee range of motion beyond 3 weeks postoperatively.
• Diagnosed osteoarthritis, rheumatoid arthritis, or other chronic joint diseases affecting the lower limbs.
• Significant injury, surgery, or persistent pain in the contralateral knee, hip, ankle, or spine that could interfere with training or gait.
• History or current diagnosis of neurological disorders (e.g., stroke, multiple sclerosis, Parkinson's disease) or vestibular dysfunction.
• Any cardiopulmonary or systemic condition that contraindicates structured physical exercise.
• Participation in other structured rehabilitation or proprioceptive training programs within the past 3 weeks.
• Cognitive impairment or psychiatric conditions that may interfere with understanding instructions or complying with the protocol.