The goal of this clinical trial stydy : is to compare between the effect of pulsed high intensity laser and extracorporeal shockwave therapy on hypertrophic scar on post burned patients.

The main questions is it aims to answer is :

• Which is more effective on hypertrophic scar post burn Extracorporeal shockwave therapy or pulsed high intensity laser therapy?
• Participants will receive the treatment for 6 weeks.
• Assesment will be don before and after treatment.

1. Subjects :

   Sixty patients have hypertrophic scar post burn. They will be selected from El Gamaa hospital and randomly distributed into two equal groups. Their ages will be ranged from 20 to 45 years.

2. Design of the study :

In this study, the patients will be randomly divided into two equal groups in number (30 patients each).

1. Group A (pulsed high intensity laser group):

   In this group of the study, thirty patients whom have hypertrophic scar post burn injury will receive pulsed high intensity laser in addition to traditional physiotherapy (deep friction massage and stretching exercises) for six weeks. The application will be three times per week.

2. Group B (Extracorporeal shockwave group):

In this group of the study, thirty patients whom have hypertrophic scar post burn injury will receive Extracorporeal shockwave therapy in addition to traditional physiotherapy (deep friction massage and stretching exercises) for six weeks. The application will be two times per week.

Equipments :

.Measurement equipments :

1. Modified Vancouver burn Scar assessment scale :

   Modified Vancouver scar scale (VSS), an observer-dependent scale of the macroscopic appearance of scarring, was used to measure changes in the scar over the period of treatment.

   The Modified Vancouver Scar Scale score is probably the most widely known scar scale that consists of three components (vascularization, pliability and scar height); the total score ranges from 0 to 11, with 0 representing normal skin.To assess 3 variables of scar characteristics: Vascularity, pliability and height.

   Scoring; vascularity ranged from 0 to 3 (1 Pink, 2 Red, 3 Purple), pliability ranged from 0 to 5 (1 Supple, 2 Yielding, 3 Firm, 4 Ropes, 5 Contracture) and height ranged from 0 to 3 (1 Less than 2 mm, 2 From 2 to 5 mm, 3 More than 5 mm). The larger the total score, the worse the HTS. The investigators choose an algebraic value for any of these characteristics based on a comparison with normal skin (zero score)

2. A Schiotz tonometer scale :

This scale will be used as an objective scale to asses the hypertrophic scar pliability and elasticity.

The tissue tonometer provides a repeatable and objective index of burn scar pliability. it is a simple, clinically useful technique for monitoring an individual's scar.

To assess scar pliability and elasticity improvement by an objective manner It is held vertically at a measured point of the scar, so the plunger moved downwards by gravity and indent the scar tissue. The instrument gives a reading on a horizontal scale numbered arbitrarily from 0 to 20, but the device does not measure scar pressure directly, a conversion table, supplied with the Schiotz tonometer pressure directly, a conversion table, supplied with the Schiotz tonometer, is used to translate the instrument readings into measurements by mmHg .

Treatment procedure :

1. Pulsed High Intensity Laser application procedure:

   • Should wear laser-protective glasses or goggles.
   • Inappropriate use of the goggles is more dangerous than their non-use, as they may provide a false sense of security.
   • Laser equipment should be placed in a controlled area with minimal access to avoid inadvertent exposure.
   • Avoid laser reflection from mirrored surfaces.
   • Avoid exposure of eyes, unclosed fontanels of children.
   • Applied at at fluence of 40 J/cm2 , pulse duration of 0.3 m/s , spot size of 5 mm in a focused mode for 3 passes.

2. Extracorporeal shockwave application procedure:

   • Patients will receive sessions of ESWT twice a week for 6 weeks.
   • ESWT will be administered on an outpatient basis; the selected treatment area is usually the most uncomfortable for the patient. Patient placed into comfortable position that allowed the vision of the treated area.
   • Each treatment region covered with 2500 to 3000 impulses with average session time 10-15 min.

conservative treatment for both groups: (Stretching exercises and Deep friction massage ) 2 sessions per week for 6 weeks

Inclusion Criteria:

• The patients age will range from 20 to 45 years.
• All patients will be free from any other pathological conditions or histories except hypertrophic scar.
• patients will be selected from both gender.
• All patients will have hypertrophic scars post burn injuries.

Exclusion Criteria:

• The patients who have open wound at or near treatment site.
• The patients who have cardiac pacemakers or other implanted electronic devices.
• The patients who have any significant health problem such as diabetes, circulatory
• disorders or history of skin malignancy in the treated area.
• uncooperative patients.
• The patients who have a deep venous thrombosis (DVT).