OATS procedure

FAQs on OATS Procedure in Gilbert, Chandler & Mesa AZ


A relatively new technique, osteoarticular autograft transfer system or OATS procedure has been gaining prominence in the last five years. A 2012 study presented at the annual conference of the American Academy of Orthopaedic Surgeons hailed the procedure as the best among available surgical methods to repair damaged knee cartilages. A higher success rate and restoration of cartilage biomechanically equal to the originals make OATS procedure a popular option.

What is OATS procedure?

OATS procedure is a surgical technique to replace torn knee cartilages with a healthy one. A piece of cartilage and bone are taken from a non weight-bearing on no-critical need part of the knee and grafted in place of the damaged cartilage.

The osteoarticular transfer procedure is found to be highly successful in patients with damaged cartilage diameter less than 1 cm. Once performed, it relieves pain, restores full knee functionality, and gives all benefits of a normal cartilage. Unlike microfracture repair, there is no inferior or scar cartilage formed as a replacement.

What are conditions treated with OATS procedure?

Osteoarticular transfer system involves moving a non-damaged cartilage portion to replace a damaged cartilage. The procedure is very effective in repairing hylane cartilage injury. It cannot be performed in case of extensive cartilage damage due to insufficient availability of healthy cartilage.

OATS procedure is for both partial and full thickness cartilage lesions and recreates the original cartilage. But it is more invasive and with longer recovery time compared to microfracture repair.

Who is a candidate for OATS procedure?

You are a candidate for OATS procedure if

  • the cartilage is partially damaged
  • there is undamaged sufficient part for taking out a graft
  • there is no deep cartilage damage
  • you are skeletally mature ( at least aged 15)
  • there is no need for total knee replacement
  • there is no relief with non-surgical therapies
  • there is minimal degenerative changes in the knee joint
  • there is no alignment or malformation deformities

How is OATS procedure performed?

The patient is placed under general anesthesia and an arthroscopic examination is carried out first to assess the damage. Next an incision is made on the knee and makes space in the damaged cartilage part using a coring tool to place the plug. A part of the health cartilage (from non-critical area) is transferred to fill the gap created earlier. The implant is fixed there. The implant grows in due course and replaces the damaged cartilage completely.

How long does OATS procedure surgery take?

It takes about 60 to 90 minutes. You don’t need to stay in the hospital more than 24 hours. Many patients are discharged within a few hours of the surgery conclusion.

What are the restrictions following OATS procedure?

  • Keep the incision area clean and dry
  • No showering of the place for 3 days
  • Rest for 4-5 days
  • No driving for six weeks
  • Use crutches for 6 to 12 weeks
  • Avoid weight bearing for 12 weeks
  • Use a brace for 12-20 weeks
  • No resistance training before 12 weeks
  • Avoid return to sports for at least for a year

What kind of rehabilitation is needed following OATS procedure?            

  • Day 1 to Week 3: Non-weight bearing workouts, CPM machine, knee extension between 0 to 90 degrees, mostly passive flexion, assisted hell slides, etc.
  • Week 3 to 6: Extension up to 110 degrees, ROM exercises for 4 hours each day, supine wall slides, therapeutic workouts, quad sets, hip strength exercises, patellar and soft tissue mobilizations
  • Week 7 to 12: No high-impact activities, but can have light progressive weight bearing and weight shifting, WB strengthening, pool drills, stationary biking, muscle stretching, single and double leg balance, etc.
  • Up to 4 Months: Functional leg strengthening, proprioception progression, squatting, leg press, step backs, core strengthening, etc.
  • Up to 8 Months: Impact and movement control workouts, multiplane and progressive velocity activities, work-specific exercises, hip and core strengthening, etc.

How long is the recovery period following OATS procedure?

Full recovery almost takes a year. You can start low-impact sports in 8 months. But high-impact sports are suggested only after 12 months.

What are the potential complications of OATS procedure?

Like other surgical methods, OATS procedure may cause swelling, pain, bruising, bleeding, infections, or temporary knee stiffness. However, infections and bleeding are rare and avoidable.


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