Biocomposite Augmentation in Revision Quadriceps Tendon Repair

Abstract

Background:

Quadriceps tendon ruptures are uncommon, typically affecting middle-aged men, often due to trauma or systemic comorbidities. Primary repairs yield excellent outcomes; however, revision surgery poses challenges due to poor tissue quality and vascularity.

Indications:

Revision repair is indicated after failed primary surgery with recurrent extensor mechanism deficit—patella baja, extensor lag, palpable defect. Magnetic resonance imaging can confirm the diagnosis and approximate reducibility. Biologic augmentation is indicated in the presence of an especially poor healing environment, poor postoperative compliance, or a high fall risk. This technique requires a reducible tendon.

Technique:

Positioning is supine with a lateral thigh post and foot positioner. The midline incision is recreated. Two No. 2 FiberWire sutures are placed in the quadriceps tendon in a modified Krackow fashion. Beath pins create 3 parallel transpatellar tunnels and shuttle the sutures through them. A No. 5 FiberWire circumferential cerclage and biocomposite shoelace are placed around the patella. With the knee in hyperextension, the transosseous sutures and suture cerclage are tied, the retinaculum repaired, and the shoelace tensioned and secured with sutures. A platelet-rich plasma-soaked biocomposite patch is secured over the repair construct before a layered closure and application of a hinged brace locked in extension.

Rehabilitation begins with weightbearing as tolerated with the knee brace locked in extension for 1 week. Thereafter, the brace can be unlocked to the degree of stress-free flexion achieved intraoperatively at rest. From weeks 6 to 12, range of motion (ROM) gradually progresses to achieve full motion by 3 months. Strengthening, especially eccentric quadriceps exercises, begins after 3 months, with activity progression as tolerated.

Results:

While the literature on revision outcomes is limited, especially for this novel technique, primary repairs show rerupture rates of 2% to 8%. Optimal outcomes—regarding ROM, strength, patient satisfaction—are associated with intervention <3 weeks. Index suture anchor fixation also carries a slightly higher risk of complications and retear compared with transosseous tunnels. These technical and chronicity considerations can serve as risk factors for patients presenting for revision repair and support prompt revision surgery when indicated.

Discussion/Conclusion:

This technique combines the structural and cellular support of biocomposite augmentation with the mechanical stability of transosseous fixation and suture cerclage, offering a comprehensive, reproducible solution for complex revision cases.

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.

Video Transcript

In this video, we will review the background, preoperative planning, patient positioning, and procedure of revision quadriceps tendon repair with biocomposite augmentation, along with potential complications, rehabilitation, and return to sports, and patient outcomes in the literature.

Background

We present the case of a 75-year-old male patient, 11 days status post suture anchor quadriceps tendon repair, who sustained a reinjury as he tripped over a rug. There was an audible pop, immediate effusion, and subsequent difficulty in weightbearing. His examination was significant for tenderness to palpation over the superior pole of the patella and a questionable palpable defect at that location.

Radiographs reveal recurrent patella baja with a Caton–Deschamps index (CDI) of 0.65. T2-weighted sagittal and axial magnetic resonance imaging (MRI) cuts show a complete retear of the distal quadriceps tendon without significant retraction.

Recurrent quadriceps tears often occur due to poor tissue quality, scar, and reduced vascularity in the setting of inadequate fixation, excessive retraction and repair under tension, and/or infection at index surgery.^6,11 As such, structural and biologic augmentation is increasingly used in revision surgical episodes. ³ However, the literature on revision techniques and their respective outcomes is limited.

Indications

Indications for revision quadriceps repair mirror those for primary repair, with suspicious radiographic and examination findings. ³ An MRI is not vital but can confirm the suspected diagnosis^1,2 and help approximate tissue reducibility and the applicability of this biologic augmentation technique in revision settings. Biologic augmentation is indicated in especially poor healing environments in the context of patient comorbidities, advanced age, or chronicity, and in instances in which the repair may be significantly stressed, such as poor postoperative compliance or those at high fall risk.^1,2 This novel technique necessitates a reducible tendon; irreducibility may be better served with allograft reconstruction. ⁴

For preoperative planning, it is important to consider the index surgical technique and whether any augmentation was used, as well as to assess the MRI for tissue quality and the extent of retraction.^2,9

Technique Description

This is a cadaveric representation of the case. Patient is positioned supine with a lateral padded thigh post and a Kirschenbaum foot positioner. A bump can be placed under the operative hip to facilitate neutral leg rotation with the patella facing straight up. A thigh tourniquet is applied but not routinely inflated.

The previous midline incision is recreated, extending roughly 4 cm proximal to the superior pole of the patella to the tibial tubercle.

Soft tissue flaps are mobilized to expose the extensor mechanism. Hematoma is evacuated. The extensor mechanism and retinaculum are investigated. Suture material is removed, and the wound is copiously irrigated. The tear site is freshened by excising scar to healthy, bleeding tissue. If the tendon is not reducible to the superior pole of the patella, improved mobilization can be achieved by sharply releasing adhesions medially and laterally, and at times, utilizing a Cobb to free the vastus intermedius from the anterior femur. If it is still not reducible in a tension-free manner, one can consider a formal V-Y lengthening, or it may favor the use of an allograft reconstruction instead. ⁴ Previous suture anchors are not routinely removed unless they loosen independently, indicating poor bone quality. A No. 2 FiberWire suture is passed up the medial and lateral margins, respectively, in a modified Krackow fashion, then back down centrally.

With the knee flexed 45°, beath pins facilitate creation of 3 parallel tunnels 1 cm apart in an anterograde fashion through the center, medial, and lateral aspects of the patella. Often, tunnels can diverge around the previous suture anchors or bone tunnels to ensure getting into new bone. This can be done freehand, using preoperative imaging as a reference, or aided by intraoperative fluoroscopy. If there is insufficient bone quantity, this would also favor the use of allograft reconstruction over augmentation. ⁴ The central pin is placed first and serves as a guide for the medial and lateral pins. These pins then shuttle the previously placed FiberWire suture tails, with 1 medial, 1 lateral, and 2 central. The central suture tails are retrieved beneath the patellar tendon to their respective medial and lateral complements.

No. 5 FiberWire is used to create a circumferential suture cerclage around the patella utilizing the Wisconsin technique. ⁵ This technique creates a purse string by slightly retreating to create some overlap with each passage and advancement of the suture. Special attention is taken to pass completely under, not through, the patellar and quadriceps tendons; thus, a larger needle radius of curvature is often beneficial. It is also important to extend the suture cerclage proximal to the previously placed Krackow sutures when traversing the quadriceps tendon.

Biocomposite augmentation is facilitated by the ConMed BioBrace, a 3-dimensional, deoxyribonucleic acid-absent, 100% type 1 collagen scaffold reinforced with poly-L-lactic acid. A biocomposite shoelace, soaked in vancomycin, is woven around the patella, starting proximally, beneath the quadriceps tendon but proximal to the previously placed Krackow sutures. This is then woven distally on both the medial and lateral margins adjacent to the tendon and patella.

The quadriceps tendon is reduced by placing the knee in hyperextension and applying tension to the biocomposite shoelace. The transosseous FiberWire sutures are then tied over the inferior pole of the patella. The suture cerclage is tied on the lateral aspect.

The torn medial and lateral retinacula are repaired with a series of 0 Vicryl figure-of-8 sutures. To easily access the far medial and lateral aspects of the torn retinaculum, it can be helpful to place those sutures from the opposite side of the patient, with medial sutures placed from the patient's lateral side, and lateral sutures placed from the patient's medial side.

Both ends of the previously woven biocomposite shoelace are retrieved underneath the patellar tendon with a right-angle clamp. It can be helpful to dilate the shoelace's shuttling path with a right-angle clamp to ensure easy passage. With the knee maintained in hyperextension to keep the tension off the repair construct, the shoelace is tensioned, then secured with FiberWire figure-of-8 sutures on the medial and lateral sides of the patella and reinforced with a series of Vicryl figure-of-8 sutures.

A biocomposite patch, which has been soaking in platelet-rich plasma (PRP) on the back table, is laid over the repair construct for further biologic augmentation. It is secured with simple Vicryl sutures, first in the corners, taking great care to avoid cutting the previously placed FiberWire Krackow sutures. Once the corners are secured, evenly spaced simple sutures can be placed to help the patch lie flat without any bunching.

The knee is gently ranged to show restoration of the extensor mechanism. The amount of flexion before stress is observed on the repair, as this guides the permissible range of motion (ROM) postoperatively. The wound is then copiously irrigated, closed in layers, and placed in a hinged knee brace locked in extension.

Results

Several complications should be avoided during this procedure. Careful placement of beath pins is necessary to prevent fracture or cartilage injury and ensure adequate fixation. Intraoperative achievement of full extension or slight hyperextension during tendon repair ensures restoration of the length-tension relationship. Wound complications are possible but may be minimized through meticulous hemostasis, watertight closure, and use of a hinged knee brace locked in extension for initial soft-tissue rest.

This is the patient's postoperative progression in this case. ⁸ Postoperatively, the patient was allowed to weightbear as tolerated with a hinged knee brace locked in extension at all times for the first week. Thereafter, he was able to unlock the knee brace from 0° to 70° while at rest. Over 6 to 12 weeks, ROM was incrementally increased with an unlocked hinged knee brace to achieve a full ROM by 3 months postoperatively. From 3 months onward, the focus was on strengthening, specifically eccentric quadriceps exercises, followed by progression of activities as tolerated.

A comparison of primary versus revision rehabilitation protocols highlights the major differences in the first 8 to 10 weeks, with revisions utilizing longer immobilization and slower progression.^4,8 The present case is a hybrid of the 2 protocols, with decisions based on an intraoperative examination under anesthesia. Regardless of the primary or revision setting, the amount of knee flexion observed before stress on the repair is the permissible ROM postoperatively. However, if the tissue or bone quality is especially poor, additional consideration is given to progressing more slowly. Casts are seldom used in the senior author's (D.C.F.) practice and are reserved for truly noncompliant patients or those at an exceptionally high risk of falls for added protection.

Discussion/Conclusion

Outcomes are sparse for revision quadriceps repair, especially utilizing this novel technique. However, after primary repairs, rerupture rates are 2% to 8%. Best outcomes, in terms of ROM, strength, and satisfaction, are seen with early repair, <3 weeks, in the primary setting.^1,9 Thus, this can be extrapolated to risk factors of patients presenting for revision repair in addition to the expediency of reoperation for best outcomes.

The transosseous tunnel technique is the traditional method for primary repair, exchanging extensive dissection for strong fixation. Suture anchors have proven to have better biomechanics, less surgical dissection, and therefore better preservation of blood supply, and shorter operative times.^1,2,7,9

However, there is a slightly higher risk of overall complications in addition to the rerupture rate with suture anchor fixation, as was observed in this case. ⁷

For mechanical repair techniques, suture anchors have significantly higher implant costs than transosseous tunnels.^7,10 BioBrace costs vary by implant shape and size, but the product is billed as an implant rather than tissue. PRP costs depend on the kit used.