Dr. Dirk Diefendorf, MD
New Patients

Dr. Dirk Diefendorf, MD


Sports Medicine | Male

101 S San Mateo Dr Ste 212 San Mateo, CA 94401 Get Directions

Care Philosophy

Board Certified Orthopedic Surgeon


Dr. Dirk Diefendorf, MD is a sports medicine doctor who practices in San Mateo, CA. He is 60 years old and has been practicing for 34 years. Dr. Diefendorf is affiliated with Mills-Peninsula Medical Center.

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Dr. Diefendorf's Experience

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Visiting Dr. Diefendorf

Dr. Diefendorf accepts 12 insurance carriers

Affiliated Hospitals

Hospital Quality
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Dr. Diefendorf's Reviews

Likelihood of recommending Dr. Diefendorf to family and friends
based on 25 total surveys (9 with reviews)
Dr. Diefendorf's Performance
  • Trustworthiness
  • Explains condition(s) well
  • Answers Questions
  • Time well spent
Office & Staff Performance
  • Scheduling
  • Office environment
  • Staff friendliness
  • Average wait time
    10 to 15 minutes
Patient Reviews (9)
in Dallas |
I rarely write reviews, I hope there's something called Negative rating. So far this is my worst hospital experience till date. I had to pay $35 as a copay, which they never collected at the visit, They didn't send a single mail nor called me in this regard. Now after an year i see than in my credit report as a collection. Simply Woow.
in san mateo, ca |
When I injured myself again I knew I was going to go back to Dr. Diefendorf and I had to change primary Drs. to do so. I had micro fracture surgery on my right knee along with the allograft procedure and cleaning up the meniscus. It is 6 months since the surgery and I feel great, walking normal and riding pain free. I was referred to Dr Diefendorf and have referred two friends to him with good results. If you need help getting back on track do not hesitate to contact Dr Diefendorf's office.
in millbrae, ca |
I suffered a fracture of my wrist on July 29th 2016. It was surgically repaired on Aug 5th and then a cast for 3 weeks. I can not say enough good things about this doctor. He is a excellent surgeon. Everything went perfectly because of his skill. He has excellent bedside manner and kept me informed on my progress at all times. I was back to work in 8 weeks Thank you so much Dr. Diefendorf
in San Mateo |
I had a total shoulder replacement last year. Completely satisfied with his personal care and communication. He is an excellent surgeon and would highly recommend him. ??M. Wolf
in S San Francisco |
I had a severe shoulder injury earlier this year. Dr Diefendorf did a rotator cuff repair which feels better every day. I would be happy to recommend him for his experience and expertise.
San Mateo, CA |
I had a broken ankle (5 months ago) which required surgery (plate & screws) and I felt I was in very good hands with Dr. D throughout the entire process. He explains thoroughly and answers questions completely. His manner is calm, supportive, compassionate and comforting. He has me back on both feet and I should be able to resume to all my normal activities soon. I recommend him highly.
in Santa Cruz, CA |
I went to Dr. D after learning that I had a partial tear to my left ACL. He and his staff made every effort to get me back to living the active lifestyle I am accustomed to living. Through his attention to detail at each appointment, every other month post-op, I was able to slowly build up the strength in my left knee. After 9 months of rigorous physical therapy and supporting strength building exercises, I have been cleared to do whichever outdoor activity I desire!
in Burlingame, CA |
I came to visit a friend in Burlingame from where I live in Sacramento. During my visit I broke my right femur and was transported (in great pain) to the nearby hospital. My surgery was scheduled for the next day but Dr. Diefendorf stepped up at the end of a very busy day and did my surgery that night. I found great comfort from Dr. Diefendorf's care. He is intelligent, competent, compassionate, and willing to listen patiently to what you have to say. I highly recommend Dr. Diefendorf!
in Pacifica, CA |
I had total knee replacements done by Dr. Diefendorf, the right knee 3/11/15 and left 1/4/16. In both cases the procedure was clearly explained to me ahead of time and the procedures went very well. I was home after 2 nights in the hospital each time. The followup care at home, therapy, was excellent. My recovery has gone quite well and I'm very pleased with the results of the surgeries Dr. Deifendorf performed to correct knee problems that have been with me for about 48 years.
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Dr. Diefendorf's Care Philosophy

Board Certified Orthopedic Surgeon

Dr. Diefendorf's experience matches your search based on the following criteria:

  •  Based on total number of patients treated over the last 12 months
  •  Specializes in Sports Medicine
  •  Board certified in Orthopaedic Sports Medicine, Orthopedic Surgery and Sports Medicine
  •  No malpractice claims found
  •  No sanctions found
  •  No board actions found

Awards & Recognition

  • Awards & Honors
    • Healthgrades Honor Roll
    What is a recognized doctor
  • Media & Publications

    Dr. Diefendorf has no media or publications listed.

Background Check

  • 0
    Malpractice Claims

    No malpractice history found for California.

    What is medical malpractice
  • 0

    No sanctions history found for the years that Healthgrades collects data.

    What is a sanction or disciplinary action
  • 0
    Board Actions

    No board actions found for the years that Healthgrades collects data.

    What are board actions

Board Certifications

Why It Matters: Dr. Diefendorf's Board Certifications

Board certification should be one of your top considerations when choosing a doctor. Board certification is an official recognition given to doctors who have met specific requirements set by national medical specialty boards in the... More

  • Orthopaedic Sports Medicine
  • Orthopedic Surgery
  • Sports Medicine

Conditions Treated

  • Adhesive Capsulitis
  • Ankle Fracture
  • Ankle Sprain and Achilles Tendon Sprain or Rupture
  • Ankle Sprains and Strains
  • Anterior Cruciate Ligament (ACL) or Posterior Cruciate Ligament (PCL) Tear
  • Ataxia
  • Baker’s Cyst
  • Bone Disorders
  • Broken Arm
  • Bursitis
  • Carpal Tunnel Syndrome
  • Chondrocalcinosis
  • Complications of Joint Prosthesis
  • Difficulty With Walking
  • Elbow Bursitis
  • Elbow Injuries
  • Elbow Sprain
  • Enthesopathy of Hip (incl. Trochanteric Bursitis)
  • Enthesopathy of Knee (incl. Bursitis of Knee)
  • Femur Fracture
  • Foot Conditions
  • Foot Fracture
  • Fracture
  • Fracture of Hand (incl. Fingers)
  • Gait Abnormality
  • Glenoid Labrum Tear
  • Gout
  • Hammer Toe
  • Hand Conditions
  • Hand Fracture
  • Hip Fracture
  • Hip Pointer Injuries
  • Hip Sprain
  • Internal Derangement of Knee
  • Joint Pain
  • Knee Dislocation
  • Knee Disorders
  • Knee Fracture
  • Knee Sprain
  • Lateral Collateral Ligament (LCL) Sprain
  • Lateral and Medial Epicondylitis (Tennis and Golf Elbow)
  • Leg Fracture Above Knee (incl. Hip)
  • Leg Fracture Below Knee (incl. Ankle)
  • Limb Pain
  • Low Back Pain
  • Non-Unions and Malunions of Fractures
  • Osgood Schlatter Disease
  • Osteoarthritis
  • Osteoarthritis of Ankle and Foot
  • Osteoarthritis of Hand or Wrist
  • Osteoarthritis of Hands
  • Osteoarthritis of Hip
  • Osteoarthritis of Hip and Thigh
  • Osteoarthritis of Knee
  • Osteoarthritis of Shoulder
  • Osteoarthritis of Spine
  • Patellofemoral Pain Syndrome or Knee Pain
  • Pelvic Fracture
  • Peripheral Nerve Disorders
  • Plantar Fasciitis
  • Rotator Cuff Tear
  • Runner's Knee
  • Scapular Fracture
  • Sciatica (Not Due to Disc Displacement)
  • Shoulder Dislocation
  • Shoulder Disorders
  • Shoulder Impingement Syndrome
  • Shoulder Tendinitis and Tenosynovitis
  • Sjögren's Syndrome
  • Sprains and Strains (incl. Muscle Tear)
  • Tibia and Fibula Fractures
  • Wrist Fracture


  • Medical School
    Northwestern University The Feinberg School Of Medicine

    Graduated in 1983

  • Internship Hospital
    University Of Southern California

    Completed in 1984

  • Residency Hospital
    University Of Southern California

    Completed in 1988

  • Fellowship Hospital
    The Southern California Orthopedic Institute

    Completed in 1989

  • Undergraduate School
    University Of California At Los Angeles

    Graduated in 1978

Languages Spoken

  • English
  • Spanish

Memberships &
Professional Affiliations

  • California Orthopaedic Association, Member


  • Sports Medicine
  • Orthopedic Surgery

Procedures Performed

  • ACL Surgery
  • Ankle Arthroscopy
  • Ankle Fracture Repair
  • Arm Surgery
  • Arthritic Shoulder Reconstruction
  • Arthroscopic Shoulder Reconstruction
  • Arthroscopic Shoulder Repair
  • Arthroscopic Shoulder Surgery
  • Dressing and-or Debridement of Wound, Infection, or Burn (incl. Negative Pressure Wound Therapy)
  • Elbow Fracture and Dislocation Treatment
  • Elbow Fracture and-or Dislocation Treatment, Closed
  • Elbow Fracture and-or Dislocation Treatment, Open
  • Excision of Femur or Knee
  • Excision of Tibia or Fibula
  • Foot and Ankle Fracture Treatment, Open
  • Foot and Ankle Fracture and Dislocation Treatment
  • Fracture Care
  • Fracture Open Reduction and Internal Fixation (ORIF)
  • Fracture and-or Dislocation Treatment
  • Glenoid Labrum Repair
  • Hand and Wrist Fracture Treatment, Closed
  • Hand and Wrist Fracture and Dislocation Treatment
  • Hip Fracture and Dislocation Treatment
  • Hip Fracture and-or Dislocation Treatment, Closed
  • Hip Fracture and-or Dislocation Treatment, Open
  • Hip Replacement
  • Joint Drainage
  • Knee Arthroscopy
  • Knee Replacement
  • Knee Replacement Revision
  • Knee Surgery
  • Knee and Leg Fracture and Dislocation Treatment
  • Knee and Lower Leg Fracture Treatment, Closed
  • Knee and Lower Leg Fracture Treatment, Open
  • Myofascial Trigger Point Injection
  • Resection or Ablation of Bone Tumor, Partial or Complete Resection of Bone, Debridement of Bone
  • Rotator Cuff Surgery
  • Shoulder Dislocation Treatment
  • Shoulder Fracture Treatment
  • Shoulder Fracture and Dislocation Treatment
  • Shoulder Reconstruction
  • Shoulder Replacement
  • Shoulder Resurfacing
  • Shoulder Stabilizations
  • Shoulder Surgery
  • Simple Fracture Care and Casting