Anterior cruciate ligament(ACL) injury is one of the most common sport injuries. The major problem after ACL reconstruction or rehabilitation program is quadriceps weakness. Previous studies suggested that cryotherapy and transcutaneous electrical nerve stimulation(TENS) can effectively reduce the arthrogenic muscle inhibition caused by experimental swelling.

Objective:

To exam the effects of 12 weeks cryotherapy and TENS on arthrogenic muscle inhibition in subjects with ACL reconstruction.

Design:

Prospective study.

Subjects:

Male subjects with isolated ACL injury, age between 18~40 years old are going to receive an ACL reconstruction surgery.

Methods:

Quadriceps activation level, quadriceps peak torque during maximal voluntary contraction and rate of force development are measure at presurgery, 3-month, 6-month after surgery. After surgery, subjects will receive 12 weeks, 3 days/week, training programs included 20 minutes cryotherapy and exercise training with TENS.

Data analysis:

Data will be analyzed using SPSS 13.0 software (SPSS Inc., Chicago, IL). One-way ANOVA will be used to analysis data.

Examination procedure:

1. Skin preparation and EMG setting.
2. Fill out knee joint function questionnaire.
3. Warmup with a stationary bike.
4. Single hop for distance.
5. MVIC test and EMG recording.
6. Endurance test.
7. Record surface EMG of vastus lateralis, vastus medialis, biceps femoris and semitendinosus during maximal voluntary contraction.

Inclusion Criteria:

• Male subjects with isolated ACL injury, age between 18~40 years old are going to receive an ACL reconstruction surgery.

Exclusion Criteria:

• meniscus lesion, bony fracture and osteochondral lesions