Patellar Tendon Rupture Research Articles

Hamstring Tendon Autograft for Chronic Patellar Tendon Rupture- A Series of Ten Cases

Patellar Tendon (PT) rupture is an uncommon injury of the knee extensors. Majority of the PT ruptures occur at the insertion site, on the inferior pole of the patella as an avulsion injury, mostly in males of <40 years of age and involving sports persons or accidental cases. A case series of 10 cases of neglected PT rupture were managed with primary repair along with augmentation with semitendinosus and gracilis (Hamstring tendons) graft. Patient follow-up was done postoperatively at 2nd week, 6th week, 3 months, 6 months, and then yearly. A knee brace was given to the patient postoperatively to immobilise the knee for two weeks. Static quadriceps strengthening exercises were started from postoperative day two. Assisted quadriceps strengthening exercises were allowed after two weeks postoperatively. Active quadriceps strengthening exercises were initiated after four weeks postoperatively. Partial weight bearing was allowed after four weeks and full weight bearing was allowed after eight weeks postoperatively. Postoperatively functional scoring was done using the International Knee Documentation Committee (IKDC) and Lysholm scores, simultaneously checking the knee range of motion, Insaal-Salvati ratio and quadriceps girth. Total of 8 males and 2 females were present with the mean age 43.9 years ranging from 38-53 years. The average period of follow-up was 25.5 months (range 12-39 months). Results were excellent with faster recovery and regain their normal physically active life around 8 months after reconstruction.

Combined avulsion fracture of the tibial tubercle and patellar tendon rupture in young athlete: An uncommon injury

Introduction: Patellar tendon rupture is a rare entity, accounting for 3% of all knee extension system injuries. In some cases, the tear is accompanied with avulsed tibial tubercle. Such concurrent fracture is extremely rare, and only a few previously cases have been described in the literature. We reported a 13-year-old male with combined avulsion fracture of the tibial tubercule and patellar tendon rupture. Case Report: A 13-year-old male junior basketball athlete presenting with left knee pain since 2 days before admission. The patient had previously fell to the ground with his left knee hitting the ground while playing basketball. Physical examination demonstrated swollen left knee. Radiographic examination suggested tibial tubercle avulsion, and magnetic resonance imaging demonstrated partial rupture of distal patellar tendon. The patient then underwent open reduction and internal fixation using single cannulated screw for the avulsed tibial tubercle, and patellar tendon reconstruction using suture anchor with ultra high molecular weight polyethylene fibers. Postoperatively, the patient was placed in a locked straight leg brace. One week after surgery, the patient began range of motion exercises and progression of weight bearing with physical therapy. At 4 months of follow-up, the patient can already weightbear, and he had regained active knee range of motion. Discussion: Combined avulsion fracture of the tibial tubercle and patellar tendon rupture in young athlete is an extremely rare case. As such, there is no guideline regarding the best treatment. In this report, we chose open surgery for anatomical reduction of the tuberosity fragment because we consider the growth plate and direct visualization of the patellar tendon. Rigorous physical therapy is of utmost importance in this patient for return to sport, as he is a young athlete. Conclusions: Open reduction and internal fixation using single cannulated screw, and patellar tendon reconstruction suture anchor might be a treatment of choice for those with combined avulsion fracture of the tibial tubercle and patellar tendon rupture in young patients.

Management of Chronic Patellar Tendon Rupture Left Knee Joint with Primary Repair Using Fiber Wire and Endo Button As A Cost-Effective and Simple Anatomical Reconstruction Without Grafts: A Case Report

Patellar tendon ruptures mostly occur in persons under 40 years of age, typically during sports activities. Neglected ruptures of the patellar tendon, defined as ruptures presenting after six weeks, are often difficult to repair, and different techniques have been described for reconstruction of this uncommon problem including the use of auto-grafts, allografts, and synthetic materials. We hereby describe a cost-effective and simple anatomical reconstruction without the requirement for grafts for chronic patellar tendon injuries. This is a retrospective study of a 29-year-old man who came to the orthopaedic clinic with the chief complaint of pain in the left knee. Pain has been felt since 2 years ago after the patient falls when were playing football. After the incident, the patient was taken to alternative therapy, but still felt the pain and difficulty moving the left knee. From the physical examination, the patient presented elevation of left patella height, localized tenderness, palpable gap below the inferior pole of the patella, and limited range of movement on the left knee. There was also a straight leg raise provocative test positive. The x-ray results were obtained patella alta with Insall-Salvatti Index was 1.6. An MRI examination was also performed, showing patella contusion and marrow edema, suspicious of soft tissue rupture, with intact ACL/PCL. The patient was diagnosed with chronic patellar tendon rupture of the left knee. At the time of surgery, it was found that the patellar tendon ruptured with remnants still on the distal part, and the cartilage was still in good condition. The next step is to perform a primary repair of the patellar tendon using fiber wire and endo button at the tibial part. Postoperative rehabilitation was carried out by starting limited ROM exercise of the left knee on day 4. Six weeks after surgery, there was an improvement in left knee ROM and improvement in walking ability. In this case, primary repair of patellar tendon using fiber wire and endo button provides good results and can be used as a costeffective and simple anatomical reconstruction without the requirement for grafts.

Patellar tendon ruptures repaired through a simple modified reconstruction using hamstrings tendon graft in obese patient: surgical technique and case report

Background: Patellar tendon ruptures are uncommon, severe, and are complex cases that require early surgical intervention. Loss of function of the extensor mechanism of the knee joint might cause severe disability and inability to hold a standing position. Case Presentation: A 34-year-old Saudi male, known to have morbid obesity (class 1), came to the emergency room complaining of severe pain in the left knee after experiencing a fall on a flexed knee while playing soccer. The patient had no other significant past medical history. In this case, the injury occurred due to a minor sports accident, and there were no predisposing factors. Thus, it was decided to do patellar tendon augmented reconstruction using a pedicled hamstring tendon, involving primary repair. After the surgery, a cast was applied on the patient's knee and retained for 3 weeks, allowing only active knee flexion and passive extension. Then, active assisted knee extension was allowed through physiotherapy for 2 months, until 75%-80% of active extension was achieved. Patient was moved to out-patient department after 3 months for further assessment. Conclusion: Patellar tendon ruptures from the tibial tuberosity are quite uncommon. When the patient has morbid obesity, acute repair of the patellar tendon through reconstruction using hamstring tendons could give a positive result with good outcome in the joint's movement.

The Utility of MRI in Evaluating Ruptures of the Patellar Tendon.

Although the identification of patellar tendon rupture is a clinical diagnosis aided by standard radiography, magnetic resonance imaging (MRI) may aid in identifying the location of the rupture and concomitant pathology. To evaluate the characteristics of patellar tendon tears needing surgical repair and to determine whether patient or injury factors were predictive of tear location. Case series; Level of evidence, 4. Consecutive patients who underwent primary patellar tendon repair for rupture between May 15, 2017, and April 10, 2020, were reviewed retrospectively. Exclusion criteria included age <18 years, surgical treatment of multiligamentous knee injury, laceration injury, and knee arthroplasty. Radiographs, MRI scans, MRI reports, clinic notes, and operative notes were evaluated. Statistical analysis was performed to determine factors associated with tear location, complications, and reoperation. In total, 147 patients and 156 tendon tears were included; 82.1% of the tears were patellar avulsions, 14.7% were midsubstance or complex tears, and 3.2% were tibial avulsions. Patient and injury characteristics (body mass index, race, medical comorbidities, presence of patellar tendinitis, mechanism of injury, Insall-Salvati ratio, and the presence of infrapatellar bone fragments) were not predictive of tear location (P > .05). Patellar tendon ruptures were able to be clinically diagnosed correctly in >99% of cases. MRI was used to evaluate 77 (49.4%) knees. Patients who underwent MRI before surgery were more likely to have a history of preexisting tendinitis (P = .015) and a lower preoperative Insall-Salvati ratio (1.68 vs 1.52; P = .017). Patient and injury factors were not predictive of tear location. The majority of patellar tendon tears were avulsion-type injuries from the inferior patella. MRI was not necessary to aid in the diagnosis of patellar tendon rupture, as 99.4% of tears were able to be diagnosed clinically without advanced imaging.

Neglected Patellar Tendon Rupture Augmentation Using Fibertape Augmentation: A Case Report

Introduction: Rupture of the patellar tendon is an uncommon problem caused by athletic activities. Delayed treatment would result in suboptimal outcomes such as quadriceps contracture, residual quadriceps weakness, and loss of knee flexion. Case presentation: 18 years old female patient with a seven-month-old injury twisting her knee comes with pain and instability and positive anterior drawer test and Lachman test. The radiology findings showed total rupture of the anterior cruciate ligament (ACL) and partial tear of the patellar tendon on the MRI right knee. We perform a direct end-to-end approximation of the patellar tendon with augmentation through the transosseous site in the patella proximally and tibial tubercle distally without using a graft with a good outcome. Discussion: This is the first reported case where a patellar tendon reconstruction is done without implants, synthetic augmentation or graft. Based on this outcome, the use of this technique could be promising for patellar tendon augmentation without graft. This might be an alternative to the less expensive method of repairing a chronic patellar tendon rupture. Conclusion: The use of fibertape augmentation provides a practical solution for treating a neglected patellar tendon rupture with concurrent ligament injury needing graft repair. We believe that this technique is easily reproducible and warrants further investigation.

Intrasubstance Patellar Tendon Repair with the Addition of a Bio-inductive Implant

Intrasubstance patellar tendon ruptures are an uncommon injury that can have devastating long-term effects for patients. Operative intervention to repair the ruptured tendon is the gold standard treatment for these injuries and can be performed using a variety of techniques. Unlike the more common patellar tendon ruptures at the level of the patella, repairs of intrasubstance ruptures are often challenging because of the poor quality of the remaining tendon fibers. Tendon repair with augmentation via bio-inductive implants has gained popularity in upper extremity literature, as it has demonstrated improved tendon strength and patient outcomes. However, there remains a sparsity of reports regarding tendon augmentation in the lower extremity literature. Here, we describe repair of an intrasubstance patellar tendon rupture using a modified SpeedBridge repair and augmentation with a bio-inductive implant.

Extensor mechanism reconstruction with allograft following total knee arthroplasty: a systematic review and meta-analysis of achilles tendon versus extensor mechanism allografts for isolated chronic patellar tendon ruptures.

Extensor mechanism rupture is a severe complication with an incidence of 0.1-2.5% after total knee arthroplasty (TKA). Achilles tendon allograft (ATA) and extensor mechanism allograft (EMA) in TKA surgery have yielded mixed clinical results. Our systematic review aims to identify the proportion of failure in extensor mechanism reconstruction after TKA using allograft and evaluate clinical and functional outcomes and the most common complications. Furthermore, we performed a meta-analysis among studies dealing with isolated patellar tendon ruptures to assess the failure rate, surgical complications, and clinical findings (extensor lag and knee range of motion) of extensor mechanism reconstruction using either ATA or EMA grafts. A systematic review of the literature was performed following the PRISMA guidelines, including the studies dealing with the use of EMA and ATA for extensor mechanism rupture following TKA. Coleman Methodology Score and the MINORS score were used to assess the quality of the studies. A meta-analysis was performed to evaluate the failure rate, complications, and clinical findings (extensor lag and knee range of motion) of the ATA and EMA treatments in isolated patellar tendon ruptures. A total of 238 patients (245 knees), with a mean age ranging from 54 to 74years, who underwent extensor mechanism reconstruction with an allograft were identified in the 18 included studies. We analysed 166 patellar tendon ruptures, 29 quadriceps tendon ruptures, and 29 patellar fractures in the analysis. A chronic injury was described in the majority of included cases. ATA and whole EMA were used in 89 patients (92 knees) and 149 patients (153 knees), respectively. The overall failure percentage was 23%, while EMA and ATA were 23 and 24%. The most common complication was extensor lag (≥ 20°). The overall incidence of postoperative infection was 7%. Eleven of 14 included papers reported more than 100° of the mean postoperative knee flexion. The percentage of patients requiring walking aids is 55 and 34.5% in ATA and EMA, respectively. The failure outcome after extensor mechanism reconstruction in isolated patellar tendon ruptures was 27%, with no statistical difference between EMA and ATA in terms of failure rate and clinical outcomes. Extensor mechanism reconstruction with allograft represents a valid treatment option in patients with acute or chronic rupture following total knee arthroplasty. Persistent extensor lag represents the most common complication. EMA is associated with a lower frequency of patients requiring walking aids at last follow-up, although it has similar clinical and functional outcomes to ATA. In patellar tendon ruptures, ATA has a comparable success rate with EMA. Level IV, therapeutic study. PROSPERO 2019 CRD42019141574.

A different unhappy triad in the knee: a case of acute simultaneous rupture of Patellar Tendon, Anterior Cruciate Ligament and lateral meniscus treated in one stage and review of literature.

We present a case report of a 43-year-old male patient with simultaneous ruptured of anterior cruciate ligament (ACL), patellar tendon (PT) and lateral meniscus tear, occurred during a tennis match. This combinate tear is not frequent, and literature reports only few cases. Clinical diagnosis can be difficult and the support of MRI and X-Ray is needed. Surgery was performed within seven days from injury in a one-step fashion. Clinical and radiological outcome treatment was successful.

Early patellar tendon rupture after total knee arthroplasty: A direct repair method.

Patellar tendon rupture after total knee arthroplasty (TKA) is a catastrophic complication. Although the occurrence of this injury is rare, it can lead to significant dysfunction for the patient and is very tricky to deal with. There has been no standard treatment for early patella tendon rupture after TKA, and long-term follow-up data are lacking. To introduce a direct repair method for early patella tendon rupture following TKA and determine the clinical outcomes and complications of this method. During the period of 2008 to 2021, 3265 consecutive TKAs were retrospectively reviewed. Twelve patients developed early patellar tendon rupture postoperatively and were treated by a direct repair method. Mean follow-up was 5.7 years. Demographic, operative, and clinical data were collected. The clinical outcomes were assessed using the Western Ontario and McMaster Universities (WOMAC) score, the Hospital for Special Surgery (HSS) score, knee range of motion, extensor lag, and surgical complications. Descriptive statistics and paired t test were employed to analyze the data. For all 12 patients who underwent direct repair for early patellar tendon rupture, 3 patients failed: One (8.3%) for infection and two (17.6%) for re-fracture. The two patients with re-fracture both underwent reoperation to reconstruct the extensor mechanism and the patient with infection underwent revision surgery. The range of motion was 109.2° ± 10.6° preoperatively to 87.9° ± 11° postoperatively, mean extensor lag was 21° at follow-up, and mean WOMAC and HSS scores were 65.8 ± 30.9 and 60.3 ± 21.7 points, respectively. This direct repair method of early patellar tendon rupture is not an ideal therapy. It is actually ineffective for the recovery of knee joint function in patients, and is still associated with severe knee extension lag and high complication rates. Compared with the outcomes of other repair methods mentioned in the literature, this direct repair method shows poor clinical outcomes.

Augmentation in the repair of traumatic patellar tendon ruptures. A novel mechanical and biological construct: Technical note

Patellar tendon ruptures are infrequent and potentially disabling injuries. These injuries are usually repaired with transosseous suture tunnels. However, this technique can produce a significant gap formation and prolonged postoperative immobilization. Although several techniques have been described to improve the integrity of the repair, the surgical technique of choice is a matter of debate especially when there is tissue loss due to high-energy trauma. This study aims to evaluate the clinical outcomes of patients with acute patellar tendon ruptures due to high-energy trauma treated with a novel construct configuration that includes a suture anchor and a figure-of-eight augmentation with hamstring autograft with medial and lateral reinforcement. To determine the clinical outcomes the International Knee Documentation Committee (IKDC) score was obtained pre-surgery and at 12 months of follow-up. A total of six patients were recruited, with a median age of 27.5 years, five of these were male. Three lesions were in the proximal pole of the tendon, two were mid-substance and one was in the junction with tibial tuberosity. The IKDC clinical score significantly increased from pre-surgery to the 12-month follow-up with a median difference of 32.8 (95% CI, 19.5–42.6, p = 0.0313). Likewise, the patients presented a post-surgery quadriceps strength level with a median of 5/5. All patients had full active knee extension with a median of 0–120°. There was no statistical difference in the range of motion comparing the surgical knee to the contralateral knee (p = 0.6883). No patient presented any type of reintervention or complication during the follow-up period. The configuration of the construct presented in the technique had not been reported before in the literature and combines the advantages of the use of suture anchors and biological augmentation with lateral and medial reinforcement. This technique may be useful in patients with traumatic injuries with and without loss of tissue. Although it is a small series with concomitant injuries, satisfactory clinical results were presented during follow-up.

Senior Military Rank Is Associated With Higher Rates of Return to Running and Unrestricted Activity Among Military Servicemembers After Surgical Repair of Patellar Tendon Rupture at 1-Year Follow-up

To evaluate 1-year outcomes in active-duty servicemembers who underwent patellar tendon rupture repair and to identify baseline variables associated with return to activity. We performed a retrospective review of all active-duty servicemembers undergoing primary patellar tendon rupture repair between 2009 and 2014. All patients had a minimum 12-month follow-up. Demographic variables were recorded, as well as ability to return to impact activities and remain on active-duty status. Rates of recurrent rupture and revision surgery were identified. Univariate analysis was performed to assess relations between outcomes and baseline variables. A total of 123 patients met the inclusion criteria (average age, 33.5 ± 6.6 years; 99% male patients) with a mean follow-up period of 4.3 ± 2.2 years. Whereas 67.4% of patients returned to running at an average of 8.3 months from index surgery, only 42.4% of patients resumed unrestricted occupational function. Higher rates of return to running were observed among patients with senior military rank (P= .046). Senior military rank was also associated with a higher rate of return to unrestricted active-duty status (P= .006). Logistic regression analysis showed an association between postoperative pain (odds ratio [OR], 0.684; 95% confidence interval [CI], 0.56-0.84; P < .001) and return to running, between postoperative pain (OR, 0.77; 95% CI, 0.60-0.98; P= .033) and return to active duty, and between rank (OR, 2.06; 95% CI, 1.04-4.07; P= .037) and return to active duty. Patients who sustained injuries during deployment had a higher rate of recurrent rupture (26.1% vs 9.3%, P= .028). At 1-year follow-up, approximately two-thirds of military servicemembers undergoing primary patellar tendon repair had returned to running after surgery, whereas fewer than one-half returned to full military duty. Younger age and more senior military rank were associated with higher rates of return to running. Additionally, servicemembers of higher rank, particularly officers, had statistically higher rates of return to unrestricted activity. Level IV, therapeutic case series.

Traumatic Midsubstance Patellar Tendon Ruptures: A Unique Surgical Repair Technique in the Setting of Poor Tissue Quality

In the setting of traumatic midsubstance patellar tendon ruptures in which the tissue is unable to be repaired end to end, surgical options are limited. We offer a technique using suture anchors for the native tendon reconstruction, allograft augmentation, and a bioinductive implant.

Therapy of chronic extensor mechanism deficiency after total knee arthroplasty using a monofilament polypropylene mesh.

IntroductionLesions of the quadriceps or patellar tendon after total knee arthroplasty (TKA) are a rare but serious complication which, if left untreated, can lead to loss of function of the knee joint. While acute and subacute extensor mechanism disruptions may have several causes, chronic deficiencies are often related to multiple prior revision surgeries for joint infection or aseptic TKA failure. Up to date, biological allograft reconstruction showed unsatisfying results. The use of a monofilament polypropylene mesh is a promising approach for this pathological condition. The aim of the present study was to evaluate clinical, functional and patient reported outcomes of this procedure in patients with chronic extensor mechanism deficiency.Materials and MethodsTwenty-eight patients with chronic extensor mechanism deficiency (quadriceps tendon rupture n = 9, patellar tendon rupture n = 19) after TKA were included in this retrospective study. None of the patients were lost to follow-up. Surgical reconstruction was performed at one institution between 2014 and 2020 with a monofilament polypropylene mesh (Marlex Mesh, Bard, Murray Hill, USA). The mean age at the time of surgery was 69 years. Patients presented with a mean BMI of 33 kg/m2. The mean follow-up period was 23 months.ResultsThe 2-year survivorship free of mesh revision was 89% [95% confidence interval (CI): 75% to 100%]. Three patients (11%) had to undergo revision because of mechanical mesh failure and received another polypropylene mesh. No further revisions were performed thereafter. Flexion was 87° (range, 30–120°) on average. The majority of patients (75%, 21/28) had a full active extension. The mean active extension lag after surgery was 4 degrees (range, 0–30°).DiscussionWe observed a substantial improvement of extensor mechanism function. The majority of patients had full extension and showed good clinical results. A failure rate of over 50% has been published for alternative procedures. Thus, the use of the described augmentation technique represents a reasonable treatment option for chronic extensor mechanism disruptions of the patellar tendon as well as the quadriceps tendon after total knee arthroplasty. However, there might be a potentially higher risk for infection persistence in periprosthetic joint infection cases due to the presence of a foreign material.

The Injury Mechanism of Knee Extensor Mechanism Rupture in Professional Athletes: A Video Analysis Study.

In Professional Athletes, quadriceps and patellar tendon ruptures are devastating injuries, often resulting in the loss of a season or a decreased return to the pre-injury level of sport. This study aimed to perform a comprehensive Video Analysis on extensor mechanism rupture (EMR) to describe the body postures and related mechanism in Professional Athletes. Using publicly available data on quadriceps tendon and patellar tendon ruptures from between 2000 and 2020, 52 elite athletes were identified. Of these, twenty-eight injuries with adequate video data were analyzed for Injury Mechanism, body posture, as well as player and sports characteristics. Of the 27 athletes included in the study, with an average age of 28.18 ± 4.96years, there were injuries in 28 extremities (1 case bilateral). The patellar tendon was ruptured in 20 cases (71.4%), and the quadriceps tendon in 8 cases (28.6%). There was total tendon rupture in 13 cases, and partial rupture in 6 cases (data for 1 case was not available). In 20 cases (70.4%), there was no contact resulting in the injury. Four of the contact injuries occurred in American football (3 direct, one indirect), 3 in basketball (1 direct, two indirect), and 1 in baseball (direct). The results of this research indicate that EMR occurs most commonly when the knee is in flexion and the ankle is in plantar flexion. There is the tendency for the knee to be in valgus at the time of injury. This information can guide physical therapy techniques, including neuromuscular training, proprioception, and balance training in the prevention of EMR in elite athletes.

Hybrid Knot and Knotless Suture Anchor Repair for Patellar Tendon Rupture

Background: Patellar tendon ruptures are the third-most common injury involving the knee extensor mechanism. They typically occur in men under 40 years old as a result of eccentric quadriceps contraction while the knee is flexed and the foot is planted.1 The optimal treatment is surgical repair within 2 weeks of injury to prevent scar formation, degeneration, and loss of tendon excursion. Indications: Operative management is generally indicated for patellar tendon ruptures. In this case, a physically active, healthy 24-year-old man presented with acute pain, extensor lag, and patella alta related to a basketball injury. He was diagnosed with acute patellar tendon rupture/extensor mechanism disruption and indicated for surgery. Technique description: We describe a technique for primary patellar tendon repair which uses both knot-based and knotless suture anchor fixation. Using a pulley effect, sutures in the inferior patellar anchors are used to reduce and repair the patellar tendon back to its bony origin. Patellar anchor-based tapes and a suprapatellar traction suture are affixed with knotless anchors to the proximal tibia to reinforce the repair. Anchor-based suture limbs are used to repair the medial and lateral retinacula. Results: The senior authors’ experience with this technique has been excellent restoration of extensor mechanism function, with rehabilitation permitting early range of motion and no major complications or failures. This patient returned to unassisted activities of daily living between 8 and 12 weeks and had returned to gym workouts and recreational sports at 12 months. Discussion/conclusion: Biomechanical studies have demonstrated that compared with transosseous repair, suture anchor repair decreases gap formation and improves ultimate load to failure. Advantages of suture anchor repair include smaller incision, less tissue dissection, shorter operative time, and improved repair biomechanics. Our technique follows a principle of tendon repair using a high number of suture and tape limbs to span the repair. In addition, this technique incorporates a “double row” of suture anchors and spans the primary repair with a suture and tape “internal brace.” 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.

Effect of Poly-L-Lactic Acid Mesh Augmentation on Cyclic Gap Formation in Transosseous Patellar Tendon Repair: A Biomechanical Study.

No previous study has investigated poly-L-lactic acid (PLLA) surgical mesh augmentation in the repair of inferior pole patellar tendon rupture. We compared the biomechanical properties of transosseous patellar tendon repair with PLLA surgical mesh augmentation to transosseous repair without augmentation. Ten matched pairs of cadaveric knees were used. Specimens in each pair were randomized to undergo the transosseous technique alone or the transosseous technique augmented with a PLLA surgical mesh. An inferior pole patellar tendon rupture was simulated and the repair procedure was performed. Specimens were cyclically loaded for 500 cycles. Gap formation was measured using two sensors placed medial and lateral to the repair site. After cyclic loading, load to failure was determined by pulling the tendon at a constant rate until a sudden decrease in load occurred. The primary outcome measure was cyclic gap formation at the medial and lateral sensors. Compared with controls, specimens that underwent PLLA mesh-augmented repair had significantly lower medial gap formation at all testing intervals up to 500 cycles (p < 0.05) and significantly lower lateral gap formation at all testing intervals from 10 to 500 cycles (p < 0.05). Transosseous patellar tendon repair augmented with a PLLA woven mesh device provided significantly greater resistance to gap formation compared with transosseous repair alone. These results suggest that PLLA mesh augmentation of the transosseous technique is biomechanically effective for patellar tendon repair.

222 Bilateral Patellar Tendon Rupture Following Low-Energy Trauma in a Young Patient Without Predisposing Risk Factors

Abstract We describe the case of a 25-year-old male who presented with a bilateral patellar tendon rupture without any of the identified risk factors for tendon injuries. Our patient is the youngest adult reported to date with confirmed bilateral, unprovoked, patellar tendon ruptures. We accompany our case with an up-to-date literature review on this topic. A degree of clinical suspicion is required for emergency room physicians as well as orthopaedic surgeons assessing such patients to avoid missing bilateral injuries. Point of care ultrasound may be utilised when there is doubt regarding the diagnosis. Prompt surgical management and a specific rehabilitation programme are both required to ensure maximum recovery of these patients.

523 Effect of the COVID-19 UK Lockdown on Lower Limb Tendon Ruptures

AimAchilles tendon ruptures are known to be prevalent in the ‘weekend warrior’, individuals who are intermittently active on a background of sedentary behaviour. There is minimal literature that looks at whether this impacts the incidence of rupture of other tendons. In the spring of 2020, a ‘lockdown’ was announced in the UK in response to the COVID-19 pandemic. In this study we aim to assess whether the incidence of lower limb tendon rupture had increased compared to other years, and whether the incidence changed as exercise allowance was increased.MethodA retrospective study was performed at a London district general hospital assessing the incidence of Achilles, patellar and quadricep tendon rupture presenting during the lockdown period, and the corresponding periods in 2019 and 2021.ResultsIn 2020 there was a significant increase in incidence of Achilles (2021: 16, 2020: 14, 2019: 8) and patellar (2021: 2, 2020: 7, 2019: 1) tendon ruptures, whereas quadricep (2021: 0, 2020: 2, 2019: 0) tendon ruptures did not differ significantly. There was an increase in the incidence of Achilles tendon rupture as exercise allowance was increased.ConclusionsThis study reinforces the necessity of stepwise return to play protocol for deconditioned athletes as well as the advantages of an active lifestyle for the general population. The results also indicate that patellar rupture may be influenced by the same lifestyle factors as Achilles rupture and should prompt larger studies across multiple sites to confirm this.

Short-Term Efficacy of Lars Artificial Ligament Reconstruction for Spontaneous Quadriceps Tendon and Contralateral Patellar Tendon Rupture in a Chronic Hemodialysis Patient: A Case Report

Background: Spontaneous rupture of the quadriceps and patellar tendons is a very rare injury that usually occurs in middle-aged to elderly patients. It’s often associated with chronic metabolic disorders, such as diabetes, hyperparathyroidism, gout, chronic renal failure, or long-term steroid use. Case Presentation: This article describes a 43-year-old man who has been on hemodialysis for 8 years due to uremia. The patient occurred pain without an obvious cause in both knees, difficulty in walking and limited extension of both knees for more than 4 months, and aggravation for more than 1 month. Conservative treatment for him was not valid. The rupture of the quadriceps tendon and the patellar tendon was confirmed according to the patient’s clinical symptoms and Magnetic Resonance Imaging (MRI). We used Ligament Advanced Reinforcement System (LARS) artificial ligament to reconstruct the patellar tendon and quadriceps tendon. The tendon and knee joint function recovered well after surgery. No infection or tendon rupture was found during follow-up. Conclusion: We report a case of the femoral quadriceps tendon and contralateral patellar tendon rupture during long-term hemodialysis. After the failure of conservative treatment, LARS artificial ligaments were used to reconstruct the ruptured tendon, and good results were obtained.