Medial Patellofemoral Ligament Reconstruction Using the Anterior Half of the Peroneus Longus Tendon Graft

Abstract

Background:

Medial patellofemoral ligament (MPFL) reconstruction is the main procedure performed for recurrent patellar instability. Choosing wisely between graft options is particularly important in this specific population, who often lacks neuromuscular control. The gracilis, semitendinosus, and quadriceps tendons are the most frequently used autografts, but harvesting can lead to reduced thigh muscle strength and poorer balance control. Studies have demonstrated safety and efficacy in harvesting only the anterior half of the peroneus longus tendon (AHPLT), with low morbidity and satisfactory functional outcomes. The AHPLT can be a convenient option for MPFL reconstruction, as it provides a solid graft without compromising muscle balance around the knee and maintains the biomechanical functions of the tendon in the foot and ankle. The objective of this article is to describe the step-by-step technique of MPFL reconstruction using the AHPLT graft.

Indications:

Suitable indications for AHPLT harvesting are patients with previously harvested hamstrings or poor muscle control in patellar instability, avoiding strength imbalance in the thigh when allograft availability is limited.

Technique Description:

A longitudinal incision is made 2 cm proximal and posterior to the lateral malleolus. The peroneal tendons are identified, and the AHPLT is tagged with a 1-Vicryl suture. The peroneus longus tendon is divided in half with a No. 11 blade, and its anterior half is sectioned anteriorly. The AHPLT is harvested through a tendon stripper. Standard knee incisions are made in the patella's medial border and the femur's medial epicondyle. The graft is passed through the interval between the second and third layers of the medial retinaculum. At 30° of flexion, the graft is fixed to the femur in the MPFL origin point and in the superomedial aspect of the patella.

Results:

A prospective study harvesting the AHPLT graft showed no significant differences between the pre- and postoperative American Orthopaedic Foot & Ankle Society scores (99.4 ± 1.14 vs 99.1 ± 1.40) after a minimum 2-year follow-up and no serious instability, pain, and muscle force decline in the ankle.

Discussion/Conclusion:

The AHPLT provides a consistent, easy-to-harvest, low-morbidity graft for MPFL reconstructions, avoiding an imbalance in the thigh in patients with poor muscular control.

Patient Consent Disclosure Statement:

The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Graphical Abstract.

This is a visual representation of the abstract.

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DOI: 10.1177/26350254251347310.M1

Video Transcript

This video presents the surgical technique for medial patellofemoral ligament (MPFL) reconstruction using the anterior half of the peroneus longus tendon graft (AHPLT).

The authors have nothing to disclose.

Background

MPFL reconstruction is the main procedure performed for recurrent patellar instability.

Graft choice is important in this specific population, who often lacks neuromuscular control.

Harvesting grafts around the knee can reduce thigh muscle strength and impair balance control.

In this context, harvesting the AHPLT provides a solid graft without compromising muscle balance around the knee. It maintains the biomechanical functions of the tendon in the foot and ankle, making it a good option for these reconstructions.

Indications

The patient is a 35-year-old woman who experienced a patellar dislocation after minor trauma 3 years ago and has since had recurrent instability.

On physical examination, she had a positive patellar apprehension test and a grade 1 J sign.

On imaging assessment, the Caton-Deschamps was 1.2, the tibial tubercle–trochlear groove distance was 13.5, and magnetic resonance imaging showed no chondral injuries. No trochlear dysplasia or intra-articular findings were present.

Technique Description

Physical examination is performed under anesthesia to confirm patellar instability.

A longitudinal incision is made in the posterolateral region of the fibula, about 2 cm proximal to the tip of the lateral malleolus.

Then, the peroneal fascia is opened, and the peroneal tendons are identified: the most superficial is the peroneus longus, and the deepest is the peroneus brevis, with a muscle belly that can facilitate its identification.

The AHPLT is tagged with a No. 1 Vicryl (Ethicon) suture.

Then, the peroneus longus tendon is divided in half with a No. 11 scalpel blade and then sectioned in the anterior direction.

After that, a tendon stripper is used to harvest the AHPLT, while the assistant keeps their thumb approximately 5 cm distal to the fibular head to prevent the tendon stripper from advancing proximally, maintaining a safety margin to avoid injury to the peroneal nerve.

The remaining peroneus longus tendon and the peroneus brevis tendon are shown.

The remaining peroneus longus tendon has robust thickness and does not require tenodesis with the peroneus brevis tendon.

The adherent muscle tissue is removed from the graft, and both ends are prepared with a No. 1 Vicryl whipstitch suture.

This is the final aspect of the graft after cleaning and preparing both ends.

In sequence, a longitudinal incision is made over the medial border of the patella. Subcutaneous dissection is performed, and the interval between the second and third layers of the medial retinaculum is identified.

The medial border of the patella is freed from the surrounding soft tissue, and a bone bed is prepared with a curette.

Then, a suture anchor is positioned at the transition between the upper and middle thirds of the medial border of the patella and fixed into the bone.

A 3-cm incision is made posterior and proximal to the medial epicondyle of the femur, and the MPFL insertion point is located between the adductor tubercle and the medial epicondyle.

A guide pin is positioned at this point and checked with fluoroscopy. ⁹

If the position is suitable, the guide pin is inserted into the femur.

The position of the guide pin is checked, and a 3-cm tunnel is drilled at this point with the diameter of the smallest interference screw available.

Then, a shuttle suture is passed through the femoral tunnel.

Another suture is passed between the second and third layers of the medial retinaculum to guide the plane of graft passage.

The graft is inserted into the femoral tunnel and then fixed with an interference screw.

The graft is then passed from the femur to the patella through the interval between the second and third layers of the medial retinaculum.

Finally, the graft is fixed in the suture anchor using a horizontal mattress suture, with the knee in 30° of flexion and the patella engaged to the trochlea.

Before finalizing the knot, tensioning of the graft is verified, allowing the patella to move 1 quadrant.

If the graft tension is proper, the knot is tied off, fixating the graft to the patella.

The second suture of the anchor is also tied to the graft. Graft tension can be adjusted if necessary.

Closure of the retinaculum is performed together with the graft, as a secondary fixation.

Last, the wounds are sutured by layers, and that is the final physical examination, showing satisfactory patellar stability.

These are the postoperative radiographs.

Results

Immediate full range of motion of both ankle and knee is allowed. Weightbearing is allowed as tolerated. Crutches are recommended for 2 to 4 weeks. Isometric quadriceps contraction and early ankle inversion and eversion exercises are recommended early in the rehab.

The return-to-sport criteria are similar to standard MPFL reconstructions. The patient may be able to return to practice 4 months after surgery if there is adequate muscle control. However, the average mean time to return is 6 months.^5,6

Discussion/Conclusion

Bi et al^1,2 conducted a prospective study on the AHPLT graft. They found no significant differences in American Orthopaedic Foot & Ankle Society scores before and after surgery and no serious instability, pain, or decline in muscle force after a minimum 2-year follow-up.

The load to failure of the MPFL in biomechanical studies was 178 ± 46 N, while the AHPLT showed an average failure load of 322.35 ± 63.18 N, similar to the semitendinosus tendon (334.1 ± 49.0 N) and higher than the gracilis tendon (225.4 ± 43.9 N) failure loads, both of which are commonly used for MPFL reconstruction. ⁷ The length of the AHPLT graft is generally sufficient for a double-strand graft, with excess length, eliminating concerns about graft size when harvesting this graft.^10,13

The AHPLT graft has been previously studied and used for anterior cruciate ligament or lateral ankle ligament reconstructions.^2,8,10,11

The contraindication for harvesting the AHPLT is a history of peroneal tendon tears.

Possible complications of peroneus longus tendon harvesting include postoperative infection, hematoma at the donor site, and paresthesia. Major complications are rare. Foot drop resulting from iatrogenic injury to the peroneal nerve has been reported in 2 cases in the literature, both of which fully recovered nerve function.^3,12 Acute compartment syndrome following peroneus longus tendon harvesting is also rare, with 3 cases described in the literature. ⁴