Abstract
Background:
Chronic patellar tendon insufficiency often results in loss of active knee extension, retraction of the quadriceps, and patella alta. This study outlines a surgical technique for patellar tendon reconstruction using an Achilles allograft with V-Y quadriceps advancement, in the context of failed prior mid-substance patellar tendon repair.
Indications:
Reconstruction is indicated in patients with complete tears of the patellar tendon that are non-amenable to primary repair. Other considerations include failed prior repair or persistent functional deficits in patients with contributing patellar tendon insufficiency. V-Y quadriceps advancement may be implemented if there are concerns for quadriceps retraction, patella alta, and inability to achieve tension-free reconstruction.
Technique Description:
The V-Y quadricepsplasty was performed initially to deliver the patella inferiorly before inferior pole suture anchors were placed. The patellar tendon reconstruction consisted of an Achilles allograft with calcaneal bone block fixation at the tibial tuberosity, augmented with distal suture fixation. Medial retinacular repair via ipsilateral hamstring autograft was incorporated into the overall construct, which was fixated at the inferior patellar pole anchors and soft tissues superiorly.
Results:
At 2 weeks postoperatively, the patient is progressing well, without complications, and the stability of the construct is maintained. Recovery of range of motion and return to full function may be expected in approximately 9 to 12 months.
Discussion/Conclusion:
This study describes a patellar tendon reconstruction using an Achilles allograft and a V-Y quadriceps advancement, with concomitant medial retinacular repair, for chronic patellar insufficiency and patella alta in a 35-year-old man. The literature supports similar outcomes for several graft options and techniques to address patellar tendon reconstruction. However, the use of Achilles allograft may be superior in terms of patient-reported pain measures.
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.
This is a visual representation of the abstract.
Video Transcript
This video demonstrates our technique for an Achilles allograft reconstruction using V-Y quadriceps advancement for chronic patellar tendon insufficiency.
Background
Chronic patellar tendon insufficiency is caused by a history of prior rupture, trauma, multiple knee surgeries, missed diagnoses, and neglect. Tendon rupture results in proximal patellar retraction, placing increased tension on the patellar tendon, making approximation and repair of the tendon more difficult. 4 Challenges in management come with loss of active knee extension, atrophy of the quadriceps, quadricep tendon retraction, and patella alta. 2 Tendon repair can be considered in acutely managed cases with adequate and viable tissue. Achilles allograft with V-Y quadriceps advancement can be used in surgical management to provide a large tissue replacement for increased bone-to-bone healing with bone block fixation and restore length to the quadriceps, improve tension, correct patellar positioning, and restore knee extension. 6
Indications
Case
The patient presented is a 35-year-old man complaining of left knee pain and limited flexion after a slip and fall on a wet surface, when he felt a pop on the lateral aspect of his knee. He underwent a patellar tendon repair 8 years prior after a patellar tendon rupture and patella fracture. Initial radiographs obtained in the emergency department demonstrated a high-riding patella, and he was subsequently placed in a knee immobilizer. He was seen in the sports clinic 2 weeks later and then referred to Atrium Health Wake Forest Baptist Medical Center for further management, where surgery was scheduled for 2 months after his initial injury.
Preoperative Planning and Examination
On examination, the patient had a well-healed surgical scar from the previous repair with slight prepatellar effusion and mild quadriceps atrophy when compared with the contralateral side. The patella was high-riding but could be manually reduced distally into the trochlear groove. Pain was noted along the lateral joint line. Range of motion assessment revealed active flexion to 90°, with extension limited to <10°. Motor strength was 2/5 against resistance, with a limited ability to perform a straight-leg raise. He was neurovascularly intact in all distributions. Patellar apprehension was positive. Stability testing demonstrated negative Lachman and McMurray tests, and no valgus or varus instability was noted.
Preoperative Imaging
Plain films of the left knee obtained in the clinic revealed bilateral patella alta, worse on the left, with an Insall-Salvati ratio of 1.7. There were no acute osseous abnormalities, and the joint space was well-maintained. A non-contrast magnetic resonance imaging demonstrated patella alta. There was a dysmorphic appearance of the patellar tendon with elongation and thickening likely associated with chronic tendinopathy, postsurgical changes, and plastic deformation. Suspected subchondral microtrabecular fractures were noted at the superior margin of the lateral trochlear facet, the posterior aspect of the lateral femoral condyle, and the superior margin of the medial femoral condyle. A small joint effusion was present. Cruciate ligaments and menisci were intact.
Technique Description
Patient Positioning
The procedure is performed with the patient in a supine position. A bump is placed under the patient's ipsilateral hip so that the knee does not externally rotate. The knee is elevated to facilitate intraoperative fluoroscopy.
Exposure and V-Y Quadriceps Flap Formation
A longitudinal anterior incision was made, followed by medial and lateral patellar flap creation. With the extensor mechanism now exposed, a V-shaped quadricepsplasty incision was created, approximately 7 cm in length, to allow for adequate advancement. Further sharp dissection was used to isolate the mid-portion of the quadriceps tendon from the surrounding soft tissue. The proximal end of the elevated V-Y flap was clamped with Allis forceps, and blunt dissection was utilized to free the quadriceps tendon from the underlying capsular tissue.
Inferior Patellar Pole Anchor Placement
Attention was then turned to the previously repaired patellar tendon. It is not shown, but with notable elongation and loss of sufficient tendon quality following a failed mid-substance rupture repair, the tendon was removed via sharp dissection along with surrounding scar tissue and remnant suture. The inferior pole of the patella is exposed and debrided to a clean base. Three parallel K wires are then placed longitudinally under direct visualization through the central third of the patella. After the appropriate position is confirmed fluoroscopically, they are overdrilled with a cannulated reamer, and three 4.75-mm suture anchors are firmly affixed for later use for primary fixation of the Achilles allograft and inferior reduction of the patella.
V-Y Quadriceps Advancement
The quadriceps flap is confirmed to be free of any remaining adhesions as the knee is ranged through flexion. The remaining proximal free margins of the quadriceps tendon are approximated and closed using a figure-of-8 technique with FiberTape suture (Arthrex). The quadriceps flap is repositioned, and the process is continued inferiorly along the length of the V-Y advancement flap, effectively delivering the patella distally about 3 cm and in line with the contralateral knee. Fluoroscopy is used to check for patella baja.
Achilles Graft Fixation
At the tibial tubercle, an oscillating anterior cruciate ligament saw blade is used to perforate the cortex to create a recipient bed measuring approximately 10 mm wide, 15 mm long, and 10 mm deep for subsequent placement of the donor bone block. A freer elevator is used to carefully remove the bone fragment and create the tibial tubercle trough. The tibial trough is further refined, and cancellous ground bone is harvested for grafting if needed. The calcaneal bone block of the Achilles tendon allograft is assessed for contouring before placement. The allograft bone block is fixed into place and seated gently using a bone tamp. The near cortex of the donor bone block is drilled with a 3.5-mm drill bit. A 2.5-mm drill bit is then used to drill to the far cortex. The depth is measured at 52 mm, and fixation of the allograft bone block is achieved by placing a 3.5 mm fully threaded screw and washer.
Appropriate positioning of the screw is confirmed on fluoroscopic imaging. The examination demonstrates bicortical fixation and stability of the bone block. The distal Achilles allograft is fixated and confirmed. Two knotless SutureTak anchors (Arthrex) are placed distally on either side of the tibial tubercle for additional Achilles allograft fixation. Horizontal mattress sutures are thrown on both sides of the Achilles allograft for increased fixation.
Medial Retinacular Repair
Ipsilateral harvest of semitendinosus and gracilis tendons was obtained for subsequent medial retinacular repair. The grafts were then tubularized in a double bundle. A transosseous suture passer is used to create a tunnel through the quadriceps tendon. Shuttling suture affixed to the prepared double-bundle graft is passed in a medial to lateral direction through the quadriceps tunnel. The hamstring graft, anchored to the proximal tibia, is then passed through the quadriceps tunnel and looped back distally on the lateral side in a box-like configuration, incorporating proximally with the suture anchors in the patella.
Final Construct Fixation
The distal end of the hamstring graft is secured via a FiberTak anchor (Arthrex) on the lateral aspect of the tibial tubercle. Here, the final construct can be appreciated. It is not shown, but the hamstring graft is incorporated proximally with the 3 patellar suture anchors. The Achilles allograft is also secured through the inferior patellar sutures and superiorly to the soft tissues. A total of 6 anchors are used.
Results
The postoperative rehabilitation plan allows the patient to remain weightbearing as tolerated in a knee immobilizer for 6 weeks with crutches as needed. Exercises, including straight-leg raises and quad sets, are started 24 hours postoperatively and performed 3 to 4 times daily. Ankle pumps should be performed throughout the day to prevent clotting. Formal physical therapy should begin 7 to 10 days after surgery. The target return to full activity is around 9 to 12 months.
As shown, postoperative films obtained at the 2-week follow-up confirm inferior reduction of the patella and stability of the construct. At the 6-week follow-up, the patient had a near full range of motion and was able to perform single-leg raises.
Discussion/Conclusion
This surgical approach for chronic patellar tendon insufficiency has shown minimal complications, primarily the risk of recurrent extensor mechanism disruption and postoperative extensor lag. 7 Studies report complication rates ranging from 6% to 47%, with autogenous hamstring tendon allografts having the highest rates, and persistent knee pain being the most common issue.1,5 Outcomes between hamstring and Achilles allografts are comparable, with mean ranges of motion at 1° to 128° for hamstring and 1° to 122° for Achilles allografts.4,5 The mean extensor lag is also similar, at 1.5° for the hamstring and 2° for Achilles allografts. However, Achilles allografts are associated with lower pain scores and higher Lysholm scores postoperatively. 4 For patients treated with direct repair, the mean knee flexion reaches 116.3°, with no extensor lag. 5 Return to sport rates for chronic patellar tendon patients are shown to range between 3 62.5% and 75%.
Here are some key tips and tricks to consider. To ensure optimal patellar height, obtain contralateral knee films to determine the native patellar height and set a proper surgical goal, preventing overtensioning. During the approach, creating generous skin flaps allows for better exposure and a wider surgical window. Using careful dissection is crucial for preserving layers and ensuring closure at the end of the case. Additionally, any prior repair sutures should be removed entirely to avoid interference with the new reconstruction. In chronic tear cases where there is significant soft tissue retraction, a V-Yplasty can be considered to restore adequate length. Harvest of both semitendinosus and gracilis tendons is dependent on surgeon preference and patient anatomy. Using both autograft and allograft may allow for better restoration of the full extensor mechanism by maximizing available tissue size and strength. Before placing suture anchors, debride and roughen the inferior pole of the patella for better fixation. Save any tibial bone removed during preparation to help fill defects after allograft placement. To enhance stability, screws should be reinforced with washers when securing the allograft. Finally, a meticulous, layered closure is essential for optimizing healing and long-term function.
Footnotes
Submitted August 6, 2025; accepted August 17, 2025.
One or more of the authors has declared the following potential conflict of interest or source of funding: B.R.W. receives research support from Arthrex, Inc.; is a paid consultant for FH Ortho; is an unpaid consultant for Sparta Science; is a paid presenter or speaker for Vericel; serves on committees for the American Academy of Orthopaedic Surgeons and the American Orthopaedic Society for Sports Medicine (AOSSM); receives publishing royalties and financial or material support from Elsevier; is an unpaid consultant and holds stock or stock options in Kaliber AI; and holds stock or stock options in Vivorte. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.
