PURPOSE:

To Compare between the effect of extra corporeal shock wave and Photobiomodulation on pain level, ROM, muscle strength, function level, dynamic balance and thickness of ligament in patients with chronic ankle instability.

BACKGROUND:

Lateral ankle sprains are the most common lower limb musculoskeletal injury incurred by individuals who participate in sports and recreational physical activities Approximately 40% of individuals who sustain a LAS develop a condition known as chronic ankle instability (CAI) (Miklovic et al., 2018), The lateral ligamentous complex is the main structure affected in 80-85% of these injuries, which are originated from a sudden inversion or supination trauma (Mansur et al., 2021).

The ligament system plays a fundamental role in the ankle's stability and includes a talocrural complex and a subtalar complex that are functionally related. For the talocrural joint, three lateral collateral ligaments are present and one medial collateral ligament (Bonnel et al., 2010).

Physical examination is mostly the first diagnostic step in the assessment of ankle injuries. Imaging modalities such as ultrasonography (US) and magnetic resonance imaging (MRI) play a major role in providing a detailed depiction of ankle tendons and ligaments (Hosseinian et al., 2022).

The effect of ESWT is Higher multiplication of collagen fibers; faster organization of muscle fibers and vascularization by treatment with radial shockwaves (Schnurrer-Luke-Vrbanic et al., 2018), ESWT could improve pain, ankle instability, ankle function, dorsiflexion ROM, and dynamic balance in patients with CAI (Le et al., 2022).

Photobiomodulation Therapy (PBMT) is effective for patients with an ankle sprain. PBMT showed high effect size with a moderate level of evidence on pain intensity and is related to the PBMT intensity and frequency (Alayat et al., 2024).

HYPOTHESES:

There is no statistically significant effect of extra corporeal shock wave versus photobiomodulation on level of pain, ROM, muscle strength, function level, dynamic balance and thickness of ligament in patients with chronic ankle instability.

RESEARCH QUESTION:

Is there any effect of extra corporeal shock wave versus Photobiomodulation on pain level, ROM, muscle strength, function level, dynamic balance and thickness of ligament in patients with chronic ankle instability?

The purpose of the study will be to investigate the effect of extracorporeal shock wave versus photobiomodulation therapy for chronic ankle instability Design of the study: A pre and posttest randomized controlled trial.

Subjects of the study:

participants will be chosen according to inclusive criteria. The sample size will be calculated depending on pilot study by power analysis (G power).

Group A: will receive exercise program include (Resistance Band Protocols, Resistance Kinematic Chain Exercises, Heel raise and Balance Exercise) at painful ankle.

Group B: as group A, plus the extra corporeal shock wave. Group C: as group A, plus the photobiomodulation

Inclusion Criteria:

- 60 participants ranging in age from 18 to 65 years from both gender with a diagnosis of Chronic lateral ankle instability stage (II) (Schurz et al., 2023).

Patients body mass index (BMI) are ranged from 18,5 to 25 (lee et al., 2022). The main presenting symptoms were ankle pain with restricted ROM that compromised activities of daily living (Schurz et al., 2023).

All ankle sprains occurring more than four weeks before inclusion both recurrent sprain and CAI patients are included (Schurz et al., 2023).

Mild to moderate severity of pain measured by NPRS scale (Srinivas, 2022). no wounds in the ankle joint and calf (lee et al., 2022). Participants had no history of ankle joint injuries or surgical procedures within the last year and injection treatment around the ankle joint within six months (lee et al., 2022).

Exclusion Criteria:

• they had any medical condition that could cause ankle pain (arthritis, fracture, rheumatiod arthritis, any deformity of ankle and neurological condition).

Any individual who had previously suffered a musculoskeletal injury or surgery that could have influenced the measurement was also eliminated.

Any individual who had diagnosed a Chronic lateral ankle instability stage (I, III).

Acute foot trauma occurring from 7 days of injury (Srinivas, 2022).