What is arthroscopic trochleoplasty?

Trochlear dysplasia is a structural abnormality in which the trochlear groove is too shallow or flat, causing the patella to slip out of place. Arthroscopic deepening trochleoplasty corrects this by reshaping the groove through keyhole incisions, allowing for precise anatomical reconstruction with minimal soft-tissue trauma.

The technique is based on:

• full arthroscopic visualization,
• controlled deepening of the groove,
• preservation of cartilage,
• stable fixation of the osteochondral flap.

This surgery creates a new, deeper groove to restore your anatomy to normal if you have trochlear dysplasia. If you simply want to know why there are clear benefits to having the procedure performed using the arthroscopic technique, scroll down to “Why Choose Arthroscopic Trochleoplasty?”.

Who Is a Candidate for the Procedure?

Arthroscopic trochleoplasty is indicated for patients with:

• recurrent patellar instability,
• high-grade trochlear dysplasia (low lateral inclination angle),
• failed previous stabilization surgery (e.g., MPFL reconstruction),
• pain caused by malalignment,
• instability during sports or daily activities.

It is particularly beneficial for young, active patients who need a quick recovery and minimal scarring. However, it is also advantageous for older patients, and I have operated on several patients around 50 years old, with the oldest being 58 years old

International patients

International patients from Europe, the UK, the Middle East, and the U.S. frequently travel to undergo this procedure. Fast recovery, minimal scarring, and expert surgical care.

Advantages Compared to Open Trochleoplasty

Arthroscopic deepening trochleoplasty offers several advantages:

• Minimally invasive (small incisions, no large incision)
• Less postoperative pain
• Faster recovery
• More precise groove shaping
• Better visualization of cartilage and anatomy
• Lower risk of stiffness
• Superior cosmetic results
• Reduced soft-tissue disruption
• Reduced heating of the cartilage flap.
• Reduced heating means a lower risk of damage to cartilage cells.
•  

Many patients return to their normal activities much sooner than after open surgery.

Surgical Technique (Step-by-Step)

The procedure includes:

1. Arthroscopic assessment of trochlear dysplasia and patellar tracking.
2. Creation of an osteochondral flap while preserving cartilage integrity.
3. Deepening of the trochlear groove to restore its correct anatomical shape.
4. Repositioning and fixation of the flap using bioabsorbable sutures and anchors.
5. Verification of patellar tracking throughout the full range of motion.
6. MPFL reconstruction.

This technique restores normal trochlear geometry and eliminates the mechanical cause of instability.

Recovery and Rehabilitation

• Most patients experience:
• immediate improvement in patellar stability,
• less pain compared to open surgery,
• rapid restoration of range of motion.
• Typical recovery timeline:
• Weeks 1–2: walking with full weight-bearing and full range of motion
• Weeks 4–6: return to full range of motion
• Month 3: light sports
• Month 6: full athletic activity is permitted if possible
• Rehabilitation is tailored to each individual based on the severity of the dysplasia and any additional procedures.

Why Choose Arthroscopic Trochleoplasty?

• This technique is ideal for patients seeking:
• anatomical correction,
• minimal scarring,
• a quick recovery,
• reduced pain,
• long-term stability,
• preservation of cartilage.
• reduced risk of arthrofibrosis
• It is one of the most advanced treatments available for trochlear dysplasia. 

About the Surgeon

Lars Blønd, MD, Orthopedic Surgeon – Patellofemoral Specialist, International instructor in arthroscopic trochleoplasty techniques. Developed minimally invasive arthroscopic trochlear deepening techniques in 2007. Has performed a large number of arthroscopic trochleoplasty procedures, not only in Denmark but also in many other countries. Author of multiple peer-reviewed publications. Speaker at ESSKA, ISAKOS, and international courses. Also author of the chapter on patellar instability in the latest European textbook published by ESSKA on arthroscopic treatments.

Contact and International Patients

Patients from Europe, the UK, and overseas frequently travel to undergo this procedure. For a consultation or referral, please contact the clinic directly.
Or email me directly at lars. [email protected]

Zoom

If you would like a second opinion regarding your MRI or just your general knee condition, I offer Zoom consultations. The cost is 225 euros.

History Arthroscopic Trochleoplasty

I used to perform open trochleoplasty. In 2007, I developed the arthroscopic technique. I began performing the first arthroscopic deepening trochleoplasty procedures in 2008. The open trochleoplasty method leaves a larger scar; furthermore, it is more painful, and the risk of scar-induced arthrofibrosis is 30%. The complication rate following this arthroscopic procedure is very low. In recent years, studies by other international groups have adopted the arthroscopic deepening trochleoplasty technique. They report results comparable to those of our three previous publications. To date, I have operated on patients from 15 different countries:

More about groove surgery

By using the pinhole technique (arthroscopic), the surgery is less traumatic for your knee, and rehabilitation is therefore likely to be faster. It should be noted that the groove procedure is usually performed in combination with a reconstruction of the medial patellofemoral ligament (MPFL reconstruction). Even the most severe cases of trochlear dysplasia can be treated with arthroscopic deepening trochleoplasty.

Heating of the Cartilage Flap

During open trochleoplasty, bone must be debrided using a high-speed burr on the posterior side of the cartilage flap, which can cause heating. This heating may impair the viability of the cartilage. During arthroscopic trochleoplasty, a constant, high volume of water flow ensures that no heating occurs.

Why also perform MPFL reconstruction?

Why isn’t groove surgery enough? And why should you also have the MPFL reconstructed? (medial patellofemoral ligament = the inner ligament of the kneecap). First of all, this is because the MPFL is always torn when the kneecap dislocates. In most cases, it does not heal on its own and therefore must be reconstructed. Furthermore, the trochlear groove does not provide stability to your kneecap until the kneecap reaches the trochlea. Importantly, this first occurs after your knee is bent about 20 degrees. This means that the MPFL is needed to provide stability to your kneecap from a fully extended knee position until your kneecap reaches the new groove at 20 degrees of flexion. There is scientific evidence to support this. Read more about MPFL reconstruction here

Arthroscopic trochleoplasty without MPFL reconstruction.

If your problem is chronic anterior knee pain resulting from a groove that is too shallow, and your kneecap is stable, then you do not need to have the ligament that stabilizes the kneecap reconstructed—for more information, see the page on anterior knee pain.

In some cases, there is a combination of trochlear dysplasia and increased femoral anteversion and/or increased external tibial torsion (kissing knees), and this must be further evaluated; otherwise, there is a risk that the outcome of the arthroscopic trochleoplasty will be suboptimal.

After surgery, you

are allowed to full weight-bearing and Full range of motion immediately after your surgery. No brace will be applied, but you will need crutches for approximately 3 weeks. You will only stay in the hospital for approximately six hours. Some patients have traveled 2,000 km back home right after surgery. Patients from Europe typically fly back three days after surgery, and patients from the U.S. return after a week. The majority begin physical therapy within 3 to 10 days after surgery. Some might find this rehabilitation regimen a little daunting, but it has proven effective for more than ten years without any problems.

Rehabilitation Protocol

After Arthroscopic Trochleoplasty and MPFL Reconstruction—by Dorte

Nielsen, Dorte Nielsen,

Proalign

.

dk. Dorte Nielsen is the physical therapist who has treated the vast majority of my arthroscopic trochleoplasty patients for more than 10 years. She often assists patients from abroad as well. She can see you both before and after surgery and guide you. She can let you know if you’re exercising too little or too much and advise you if anything seems out of the ordinary. Here is a link to her website.

Frequently Asked Questions (FAQ)

How severe is my trochlear dysplasia?

This is a common question, and it is usually addressed during an online consultation.

Is surgery mandatory? Or are there any conservative treatment options available?

This is typically discussed during an online consultation.

How long does the surgery take?

The procedure typically lasts between 1.5 and 2.5 hours.

When can I put my full weight on the leg?

Starting on day one, with crutches to help maintain balance.

When can I fly back home?

This depends on the distance. Most European patients fly home after 3 days, and patients from the U.S. usually return after about a week. A seat that allows you to straighten your leg may be necessary.

Do I need crutches?

Yes. Crutches are normally used for 2–4 weeks, depending on how quickly you recover.

Do I need a brace after surgery?

No brace is required. Full weight-bearing and full range of motion are permitted immediately.

Should I try a less invasive procedure first?

No. If trochlear dysplasia is the underlying cause, a single successful surgery is usually sufficient. Performing “smaller” procedures first often leads to repeated failures.

Is only one knee operated on?

Yes. Only one knee is operated on at a time. About one-third of patients have dysplasia in both knees.

How long does recovery take?

The knee improves over the course of 1–2 years. Most patients feel fairly well after 3 months.

Why isn’t this procedure more widely used globally?

Arthroscopic trochleoplasty is technically demanding and requires extensive arthroscopic experience. Many surgeons continue to use the open technique because it is familiar, not because it is better.

When can I return to work or sports?

Sedentary work is usually possible after about 4 weeks. Light exercise can typically resume after about 6 months.

Do I need anticoagulant medication?

Yes, if you are 30 years old or older.

Do I need a CPM machine?

No. You’ll perform active exercises on your own starting immediately after surgery.

Do I need physical therapy?

Yes. Rehabilitation is essential. Many international patients work with physical therapist Dorte Nielsen (Proalign.dk), who has extensive experience with trochleoplasty recovery.

Will I receive a postoperative plan?

Yes. You will receive a clear plan. You may put your full weight on the leg and move freely, but you will need crutches for the first few weeks.

How long is the sick leave?

This depends on the type of work and how you commute from home to work or school. At least one week of sick leave is recommended.

Will my insurance cover the surgery?

In most cases, yes—including travel expenses. The procedure is often significantly less expensive than similar surgery in the U.S.

What is the cost of an online consultation and MRI evaluation?

225 euros. MRI scans can be sent via email, Dropbox, WeTransfer, or similar services.

What is the price for combined arthroscopic trochleoplasty and MPFL reconstruction?

Approximately 11,000 euros, including implants (the cost of the implants alone is about 2,000 euros), and that includes any follow-up visits.

How often do complications occur?

To my knowledge, there have been no deep infections to date (2026). One case of arthrofibrosis. One case of patellar redislocation due to increased femoral anteversion. Three cases of deep vein thrombosis, all in patients over 30 years of age.

How can stiffness and arthrofibrosis be prevented?

It is important to prevent stiffness by performing range-of-motion exercises starting on the first day after surgery.

What is the risk of the patella dislocating again after surgery?

One patient experienced a redislocation, and I have performed more than 300 surgeries. This was the ninth case in the initial series (2009). I failed to recognize that the patient had severe femoral anteversion. Since then, there have been no redislocations.

Do I offer postoperative follow-up for international patients?

Yes. Follow-up can be conducted both in person and online, depending on your location and needs. I’m always interested in hearing how things are going!

Why Patients Travel to Denmark for Arthroscopic Trochleoplasty

• Minimally invasive technique: Arthroscopic deepening trochleoplasty preserves cartilage, reduces pain, and allows for faster rehabilitation compared to traditional open surgery.
• High surgical volume and experience: This technique has been performed for many years with consistent results, making Denmark one of the leading centers for the treatment of trochlear dysplasia.
• Accurate diagnosis and individualized planning: Detailed MRI evaluation ensures that trochlear dysplasia, patellar tilt, patella alta, and rotational issues are correctly identified before surgery.
• Short hospital stay and safe travel timeline: Most European patients return home after 3 days, and U.S. patients typically travel back after about a week.
• Clear postoperative instructions, full weight-bearing, a full range of motion, and structured physical therapy make recovery straightforward for international patients.
• Transparent pricing: Surgical costs are significantly lower than in many countries, and insurance often covers both the procedure and travel expenses.

More About Science

I have published the following peer-reviewed scientific papers. In addition, I have contributed to several papers on trochlear dysplasia and authored the one and only book on the subject.

• 1. Blønd L. and Schöttle P. Arthroscopic deepening trochleoplasty. PDF Version
• 2 Blønd L., & Haugegaard M. Combined arthroscopic deepening trochleoplasty and reconstruction of the medial patellofemoral ligament for patients with recurrent patella dislocation and trochlear dysplasia. PDF Version
• 3. Blønd L. Arthroscopic deepening trochleoplasty—The technique. PDF Version
• 4. Blønd L. Arthroscopic deepening trochleoplasty for chronic anterior knee pain following previous failed conservative and arthroscopic treatment. Report of two cases. PDF Version
• 5. Blønd L, Barfod KW. Trochlear Shape and Patient-Reported Outcomes After Arthroscopic Deepening Trochleoplasty and Medial Patellofemoral Ligament Reconstruction: A Retrospective Cohort Study Including MRI Assessments of the Trochlear Groove. PDF version

Medical Disclaimer:

The information on this page is general and cannot replace a personal consultation, physical examination, or MRI evaluation. Surgical decisions regarding trochlear dysplasia and patellar instability should always be based on an individual assessment by a qualified orthopedic surgeon. If you experience pain, instability, or knee symptoms, please seek medical advice.

Online Consultation

If you have been diagnosed with trochlear dysplasia but are unsure of its severity, you are welcome to schedule an online consultation. The same applies if you are considering traveling to Denmark to undergo surgery with me. The cost for an online consultation is 225 euros. You must send me the MRI (DICOM files). Once I have received the MRI, we can schedule a time to meet online.

Author

Lars Blønd, MD

Orthopedic surgeon with international expertise in trochlear dysplasia. Author of the first scientific book on trochlear dysplasia. Developed and researched the arthroscopic trochleoplasty procedure. Also author of the chapter on patellar instability in the latest European textbook published by ESSKA on arthroscopic treatments.

Booking
Aleris Hospital Søborg

Gyngemose Parkvej 66, 2860 Søborg

Phone +45 38170700
Email [email protected]

Below is more information for the tech-savvy

Video

Arthrex, the company that originally helped me develop the technique, has now also produced a video in 4K quality— watch it hereBe sure to read what some patients have to say on the testimonial page—or watch this YouTube video titled “Trochleoplasty Gathering” (in Danish but with English subtitles)

Why should I also have a groove surgery and not just MPFL reconstruction?

That is a good question and some surgeon argue that it is not necessary. Maybe it is not 100% necessary if you just want stability, but if you also want a knee without anterior knee pain, trochleoplasty have to be done. Also, sometimes I see patients having trochlear dysplasia and who have had an MPFL reconstruction only. Then after some years the kneecap starts to becomes loose again because the MPFL reconstruction get loose by time. Therefore if you visit a surgeons, who do not do trochleoplasty surgery, and you do have this flattened groove. Most importantly try to get a second opinion in case this surgeon tells you that the surgery is rare, dangerous and complicated surgery since this is not correct. 

Case Study - Mikkel

Mikkel was the first patient to undergo arthroscopic trochleoplasty, back in March 2008. He had previously undergone unsuccessful surgery to stabilize his kneecap, and both his doctor and physical therapist had told him he would never be able to play sports again. Most notably, Mikkel had been experiencing problems in both knees since he was 8 years old and had never been able to run. Finally, at the age of 29, he underwent surgery on both knees using the groove technique. That meant 21 years without running.

Follow-up on Mikkel

Today, Mikkel’s knees are doing well, and he is running and playing soccer. He says the only nuisance is the sound his knees make when he climbs stairs. Go to YouTube and listen to his story and others from the 2014 trochleoplasty gathering. Many thanks to Asker Blønd—my son—who created this video. Click here trochleoplasty gathering.or check out this video

Outcome after trochleoplasty

In general, the outcomes following groove surgery are very good, with fewer than 2 percent of patients experiencing new dislocations. As a result, quality of life improves dramatically. I have been following all my arthroscopic trochleoplasty patients for more than 18 years now, and on average, there have been improvements in all measured parameters and a high level of satisfaction.  Both the technique and the results of this procedure have been published in peer-reviewed journals. To date, I have presented the “Arthroscopic Deepening Trochleoplasty” technique in the United States, Japan, the Netherlands, the United Kingdom, Sweden, Norway, Poland, Germany, Austria, Portugal, and China. Furthermore, the procedure has been adopted by other surgeons and is now performed in fifteen different countries worldwide.

Tibial Tubercle Osteotomy =TTO

What about having a TT osteotomy instead of groove surgery? Several studies suggest that groove surgery yields better results—read more here. We know that trochleoplasty surgery restores normal anatomy. Furthermore, we know that patients who have undergone TT surgery a decade ago are experiencing declining outcomes. The first trochleoplasty patients I operated on more than 19 years ago are still doing well. So based on this and my clinical experience performing both many tibial tubercle osteotomies and trochleoplasty surgeries, I strongly recommend that you undergo trochleoplasty if you have trochlear dysplasia. Unfortunately, many orthopedic surgeons say that they do not perform trochleoplasty and therefore recommend TTO; instead, they must refer you to someone who performs trochleoplasty—preferably arthroscopic trochleoplasty. 

Here is the latest paper on arthroscopic deepening trochleoplasty here or simply go to the page where you can find all my scientific papers

Photo gallery with some examples of arthroscopic trochleoplasty

 Here is the latest paper on arthroscopic deepening trochleoplasty here or simply go to the page where you can find all my scientific papers