Persons with anterior cruciate ligament injury (ACL) for whom all inside technique ACLR is

planned under Ortho III unit, will be assessed for eligibility and will be included after a

written consent by the Principal investigator. Pre-operative assessment will be done, which

will include assessment of muscle girth using inch tape, muscle strength using Modified

Oxford scale, pain using Visual Analogue Scale (VAS score), active ROM using Goniometer,

Quadriceps Hamstring Index (Q/H index), electrical muscle activity of the hamstring muscle

using surface EMG electrodes and Functional activities using 3 meter hop test, and Lysholm

score. After the initial assessment the subjects will be given a short-term prehab which will

include knee strengthening and range of motion exercises, to continue till the day of surgery

and the rehabilitation protocol will be explained. (APPENDIX -1) To ensure homogeneity,

subjects who have undergone surgery by the same Orthopedic surgeon(Co-investigator) and

his team will be recruited. Following surgery, supervised physiotherapy will be given and all

the patients will be following the rehabilitation protocol from post-operative day 1(POD 1).

On POD 3, assessment of pain, muscle strength and active knee ROM will be done.

Computer generated randomization will be done; sequentially numbered, opaque sealed

envelopes (SNOSE) will be used for allocation concealment and the subjects will be

randomly allocated to one of the two groups from POD 3. Group I will receive eccentric

exercises and Group II will receive concentric exercises for quadriceps strengthening for 2

weeks. In addition, both these groups will be following the exercises of Phase I of the

rehabilitation protocol (Phase I: Immediate Post-operative period, 1 to 2 WEEKS). At the end

of 2nd week reassessment of pain, muscle girth, muscle strength, active ROM and function

will be done.