Abstract
A quadriceps tendon rupture is a traumatic injury of the quadriceps insertion on the patella leading to a disruption in the knee extensor mechanism. Diagnosis is usually made clinically with a palpable defect proximal to the superior pole of the patella coupled with the patient’s inability to perform a straight leg raise and confirmed on radiographs, ultrasonography, or magnetic resonance imaging scan. When the extensor mechanism is disrupted, operative repair is indicated. Two common techniques have been described for repair: the transosseous) repair and the suture anchor repair, and both have shown good clinical results. Nevertheless, gap formation is always a concern, and there is no consensus if one technique is superior to the other in this matter. We propose a low-cost, tensionable, transosseous anatomic repair that results in a tight construction.
Technique Video
Technique Video
See video under supplementary data.
The optimal technique for quadriceps tendon rupture repair remains a matter of debate, with some authors defending suture anchor (SA) fixation over transosseous (TO) tunnel techniques.1-4 A systematic review performed in 2022 by Onggo et al.1 showed that SA fixation displays a better biomechanical profile with smaller gap formation compared with TO techniques. Although SA repair has been proposed by some authors as showing less gap formation in biomechanical studies, its clinical benefits remain unproven. In addition, those techniques can be technically challenging, risking anchor pullout (specially in patients with osteoporosis), and are significantly more expensive. The main purpose of this technique is to allow an adequate, anatomical, biological, and tight repair by pretensioning the repair using 4 sliding knots, before tying the Krackow suture tapes. The detailed surgical steps are demonstrated in Video 1.
Surgical Technique
Positioning, Exposure, and Debridement
The patient is placed supine on an operative table with the knee flexed at 30°, with a lateral post at the level of the padded noninflated tourniquet and a foot roll to prevent the hip from externally rotating (Fig 1). This position allows easy drilling of the TO patellar tunnels. A midline incision from the midportion of the patella and extending proximally is made to expose the quadriceps tendon rupture and the retracted tendon stump. Evacuation of the hematoma and debridement of all scar tissue are performed.
Tendon and Proximal Patellar Insertion Point Preparation
The quadriceps tendon stump is trimmed to obtain good-quality tissue of the tendon end for repair. The proximal pole of the patella also is prepared by removing scar tissue and, with a curet or rongeur, cancellous bleeding bone is exposed for the tendon reattachment (Fig 2).
Suture Passage
Two 1.3-mm suture tapes (Arthrex, Naples, FL) are passed in the tendon using a Krackow-type suture. The sutures enter the anterior-posterior midportion of the tendon, and one starts in the most medial and the other in the most lateral part of the tendon. Four to five Krackow sutures are passed before converging both sutures to the midportion of the tendon, finishing by exiting again in the anterior-posterior midportion of the tendon end, in the central part of it (Fig 3).
Then, 3 polydioxanone (PDS) 1 sutures (Ethicon, Cincinnati, OH) are passed in a single loop 1 cm proximally to the tendon end, entering anteriorly and exiting posteriorly. They are placed medially, centrally and laterally in the tendon. One last 1.3-mm suture tape (Arthrex) is also placed centrally in the tendon. It is passed 1 cm proximally to the tendon end, in a single loop, with entry on the anterior side and exit on the posterior side (Fig 4). The final suture configuration is shown in Figure 5.
Patellar TO Tunnels and Suture Passage
The knee is bent to 30° and 3 TO tunnels in the patella are drilled with a 2.4-mm guide pin with an eyelet on the medial, central, and lateral portion of the patella. Care is taken to avoid iatrogenic cartilage damage (if the drilling is too deep) or anterior cortical disruption (if the drilling is too superficial). A radiograph scan can be used at this point to ensure proper placement of the guidewire, although the authors deem it not usually necessary (Fig 6).
In the central tunnel, the central inferior limb of the PDS 1, the inferior limb of the central suture tape, and the 2 central limbs of the medial and lateral suture tapes are shuttled. In the medial and lateral patellar tunnels, the medial inferior and the lateral inferior limbs of the PDS 1 and the medial and lateral limbs of suture tapes of the Krackow suture, respectively, are shuttled (Fig 7).
Sequential Knot Tying to Ensure Tight, Circumferential, Anatomical Repair
We now have the 4 Krackow suture tape ends, the single inferior limb of the central suture tape, and the 3 inferior limbs of the PDS 1 exiting in the inferior pole of the patella. The point of this technique is to provide tension to the repair, by first securing the central suture tape and PDS 1, before tying the final Krackow suture tape. This prevents loosening and strengthens the reconstruction. The assistant holds all free ends and puts tension in the repair. Then the surgeon sequentially ties the central suture tape using a sliding knot to reduce the tendon end to its original insertion site (Fig 8).
Then, the PDS 1 are tied in the same manner from lateral to medial. We use the SMC knot.5 The central suture tape together with the PDS 1 allow good amount of tension and a strong reduction of the tendon end in the proximal patella pole (Fig 9).
Also, both the central suture tape and the PDS have been passed around the tendon, which, together with the tapes later tied, will increase the contact area between the insertion site and the tendon, allowing a more anatomic and biological repair. Afterwards, we sequentially tie the medial and lateral Krackow suture tape ends. The medial suture tape ends (one exiting medially and the other centrally) are tied first, followed by the lateral suture tape, in the same fashion. This will finish the repair construct of the tendon (Fig 10). A schematic of the final construct is shown in Figure 11.
Closure
After closure of the medial and lateral retinacula, we perform a final lavage, and the wound is closed in sequential layers. The skin is closed with staples.
Postoperative Rehabilitation
Postoperatively, the patient is placed in an extension brace for 2 to 4 weeks and is allowed full weight-bearing with crutches as tolerated, with a focus on quadriceps activation. Physiotherapy starts at 2 weeks after the removal of the stitches to slowly regain flexion. Patients are expected to progressively recover flexion, as tolerated without restrictions. After 3 months, the patient should be able to perform a straight leg raise without lag and have full flexion.
Discussion
When evaluating failure type, both SA and TO constructs most commonly fail via knot slippage.6 Knot strength is directly related to knot material, surgeon experience,7 and the number and type of knots thrown.8 Systematic reviews comparing TO tunnels and SA repairs have demonstrated similar outcomes regarding gap formation and overall repair integrity.9 In this technique, we do a sequential knot tying to ensure tight, circumferential, anatomical repair using the SMC knot for the adequate tension and reduction of the tendon on the patella (Video 1), that can possibly help reducing gap formation. The tensioning principle employed in our technique facilitates secure knotting of subsequent sutures by initially reducing and stabilizing the tendon, similar to a recently described technique for medial meniscus posterior root repair.10
The limitation of our technique is that it has not yet been biomechanically tested, even though part of the repair is known and has been proven to be effective, and this modification only aims to improve even further the strength of the repair. Future studies that prospectively evaluate clinical outcomes between this technique and other techniques are necessary to appropriately assess their impacts on clinical performance. The advantages and disadvantages of this repair method are presented in Table 1. Key pearls and pitfalls are outlined in Table 2, providing a practical guide to optimizing the surgical approach and avoiding common errors.
| Advantages | Disadvantages |
|---|---|
| The tension provided by this technique avoids the loosening of the suture tape repair while knot tying | Larger incision |
| Low cost | Soft-tissue irritation as the result of prominent knots |
| Use of absorbable materials | |
| Anatomical repair by adding circumferential sutures | |
| Less hardware | |
| Simple technique | |
| Avoids the anchor pullout problem |
Table 1
Advantages and Disadvantages of a Low-Cost Tensionable Quadriceps Tendon Rupture Repair Using Transosseous Tunnels
| Pearls | Pitfalls |
|---|---|
| Any soft tissue located superiorly to the site of the quadriceps tendon insertion in patella should be fully debrided. | Any remaining slack in the Krackow suture tapes may result in elongation at the repair site |
| After each suture tape pass, remove any slack to provide an optimal Krackow configuration. | Failure to achieve a correct sliding knot with the PDS 1 or with the central suture tape, may contribute to loss of reduction, undermining the purpose of this technique. |
| Ensure that the PDS 1 and central tape sliding sutures are appropriately positioned between the Krackow sutures, to prevent cutting through the longitudinal fibers of the quadriceps tendon. | If excessive force is applied, the PDS 1 may break, undermining the purpose of this technique. |
| Accurately position the tunnels, with a safe distance between them, while avoiding both cartilage or anterior cortex perforation | |
| Place the exit tunnel near the inferior pole, to avoid anterior soft tissue knot irritation. |
Table 2
Pearls and Pitfalls of a Low-Cost Tensionable Quadriceps Tendon Rupture Repair Using Transosseous Tunnels
PDS, polydioxanone.
Disclosures
All authors (J.L., G.M., M.O., A.G., C.Q., J.R., L.F.) declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Supplementary Data (1)
Video 1
The patient is positioned supine on the operating table, with a hip and foot roll allowing 30°of knee flexion. A standard midline incision is performed. Upon exposing the rupture, the proximal pole of the patella is debrided of fibrous tissue, and cancellous bleeding bone is exposed using a rongeur and curette. Two 1.3-mm suture tapes are passed into the tendon using a Krackow suture technique. The sutures start at the most medial and lateral parts of the tendon and after 4 to 5 Krackow sutures, they converge towards the midportion, exiting centrally. In addition, 3 PDS 1 sutures are placed in a single loop, 1 cm proximal to the tendon end. These sutures are positioned medially, centrally, and laterally. One final central suture tape is also passed in a single loop, 1 cm proximal to the tendon end, from the anterior to the posterior side. With the knee maintained at 30 degrees of flexion, three transosseous tunnels are drilled through the patella using a 2.4-mm guide pin. This procedure should be done medially, centrally, and laterally. Care is taken to avoid cartilage damage or cortical disruption. The sutures are passed sequentially through these tunnels. In the central tunnel, the 2 central limbs of the Krackow sutures are passed along with the inferior limb of the central PDS and the central suture tape. In the medial and lateral tunnels, the medial and lateral limbs of the Krackow sutures and the inferior limbs of the PDS of the respective side are passed. Here, we can easily see the gap between the quadriceps tendon end and the place in the patella where it should be attached to. Now, the tensioning and tying process begins. The assistant holds all free suture ends while maintaining tension. The surgeon ties the central suture tape using a sliding knot to reduce the tendon to its original insertion point. Here you can observe the tendon gradually returning to its anatomical position as the knot is tied. Then the medial, lateral and central PDS sutures are also tied using a sliding knot, providing a strong and anatomical reduction of the tendon onto the proximal pole of the patella. Allowing the final Krackow suture tapes to be tied securely without tension, preventing loosening. Finally, the medial and lateral Krackow suture tapes are sequentially tied to complete the reconstruction. This combination of sutures increases the contact area between the tendon and its insertion site, promoting a biological robust repair. After confirming the stability of the repair, both retinacula are closed. The wound is carefully irrigated and closed in sequential layers. The skin is closed with staples. (PDS, polydioxanone.)
References
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