For an Appointment: (480) 964-2908

Request Dr. Hansen by name

Sports Medicine & ShoulderSpecialist in Gilbert Arizona
Matthew L. Hansen, MD

Matthew L. Hansen, MD

Orthopedic surgeonBoard Certified in Orthopedic SurgeryBoard Certified in Sports Medicine

ACI Vignette

Patient Vignette – Autologous Chondrocyte Implantation


P.C. is a 47-year-old female. She is an active person. She began having pain in her left knee approximately 2 weeks prior to her first clinic visit. This was the first time she experienced problems with her knee. Looking back, P.C. cannot recall any specific injury, but symptoms did begin after an aggressive workout at the gym. She reported pain along the medial side of the knee, and loss of range of motion in extension. P.C. was working as a nurse, and was unable to complete tasks required for her job, and it was increasingly challenging to feel like an actively involved mother to her young children. She decided to have her knee evaluated by an orthopedic surgeon.

Clinic Visit #1

After completing paperwork in the waiting room, P.C. had X-rays to allow for a complete evaluation. When the provider entered the room, P.C. started by giving a thorough history related to the knee injury. She described the onset of symptoms, and loss of motion. The provider then did a series of exams, including a careful evaluation of both knees, and several maneuvers to test for discomfort to the touch (very tender medially), range of motion and strength. There was tenderness along the medial side of the knee and large swelling in the joint. The knee was unable to extend fully, even when manipulated manually.

X-rays showed no abnormalities of bone or joint space, but did demonstrate swelling in the joint.

Abductor Preop AP Arrows
Abductor Preop AP Arrows

The provider was concerned for meniscus tear given the loss of motion and pain on exam. An MRI was ordered to further evaluate the knee.

Clinic Visit #2

P.C. had her MRI done and presented back in clinic to review the findings. The provider reviewed the MRI with her on the iPad. Fraying of the medial meniscus and an area of full-thickness cartilage damage were seen. [MRI_ACI_MFC defect_arrows.jpg] (In the picture, note the white, fluid filled defect at the red arrow, compared to normal cartilage at the white arrow.) A decision was made to proceed with Autologous Chondrocyte Implantation (ACI). This would be a 2-surgery process. Time was taken to review all the pre-operative testing and ask questions about the surgery.

MRI_ACI_MFC defect_arrows
MRI ACI MFC Defect Arrows

P.C. was referred to her primary care doctor for physical examination and testing such as a chest X-ray, blood and urine analysis, and EKG. This was coordinated by the surgeon’s office, but P.C. was actively involved in insuring all the tests were done in a timely manner.

Surgery #1

For 2 days prior to surgery P.C. used a special soap while showering that decreases the amount of bacteria in the skin. She received a call on the afternoon prior to her surgery with final arrangements and surgery time. P.C. was at the hospital 2 hours before her surgery time to check in to the hospital, start her IV, and sign the requisite paperwork. The surgeon signed her leg, and P.C. was wheeled off to the operating suite.

The first surgery consisted of an arthroscopic partial meniscectomy (trimming of the meniscus tear), stabilizing of cartilage at risk for breaking free, and a cartilage biopsy. Damage in the knee is seen in the pictures, both initially and after stabilizing the borders.

ACI-surgery1-MFC Defect
ACI-surgery1-MFC Defect Smooth

Please see more information about details of the surgery itself here P.C. was discharged home after less than 2 hours in the recovery room.

After the Surgery

Things happened quickly after P.C. was discharged home. She started therapy within just a few days, and was given exercises to do at home. P.C. recalls taking the pain medication for less than 2 weeks on a regular basis, but would occasionally take a pill prior to therapy. She used the crutches between surgeries to avoid further damage to the area of the bone to be grafted.

The cartilage biopsy taken during surgery was sent to a lab in Boston to grow more cartilage cells. This process takes about 6 weeks. Information regarding the process in the lab can be seen here.

Surgery #2

The second surgery occurred approximately 8 weeks after the first. The pre-surgical time progressed as with Surgery #1. The surgeon signed her leg, but this time the anesthesiologist administered a nerve block, which numbed the leg for surgery. P.C. was then wheeled off to the operating suite.

The second surgery consisted of implantation of the cartilage cells. This surgery was done through a large incision on the front of the knee. Please see more information about details of the surgery itself here. A picture of her knee before and after graft placement are pictured.

ACI Open Initial
ACI Open Initial
 ACI Open Final
ACI Open Final

P.C. spent one night in the hospital, and was appreciative that she could have pain medication through the IV when the nerve block wore off during the night. By morning she was eating well and tolerating the medication by mouth. She was discharged to home by about noon.

After the Surgery

Recovery from the second surgery was more challenging that the first. Therapy progressed slower, and there was more pain. A CPM (continuous passive motion machine) was used daily for at least 6 hours to help shape the transplant to match the surrounding cartilage. At times P.C. was frustrated with her progress, but as time progressed she began to notice significant improvement.

Post-Operative Clinic Visits

P.C. reported back to the surgeon about 2 weeks postop to have her sutures removed. She was seen every 4-6 weeks for the first 6 months. She was able to discontinue crutches at 6 weeks, but still used them occasionally for comfort. P.C. noted that the resolution of pain was a gradual process, primarily over the first 6 months.

Recovery was not without hiccups. P.C. reported multiple times at follow-up visits that she was still experiencing discomfort and the sensation of mechanical symptoms. The knee would often swell with extended standing or walking.

How Is She Doing Now?

Today the patient reports she is very happy with her surgical outcome. She has returned to many of her favorite activities, and has returned to her job as a nurse in the operating room. While there are certain movements that create a minimal amount of discomfort, P.C. reports that she has excellent range of motion and pain that is significantly better than before surgery. She considers recommendations like avoidance of repeated impact activity. Now approximately one year from surgery, P.C. is happy to have done it, and happy to have it done!

AOSSM AAOS: American Academy of Orthopaedic Surgeons® / American Association of Orthopaedic Surgeons® ORS | Orthopaedic Research Society ARIZONA ORTHOPAEDIC SOCIETY OrthoArizona