Adult native knee extensor mechanism ruptures

Bilateral rupture of the quadricipital tendon in patients with chronic kidney disease: The peculiarities of management (case report)

INTRODUCTION

Bilateral forms of quadricipital tendon rupture are rare. They are usually associated with predisposing factors, such as secondary hyperparathyroidism due to chronic renal failure, which need to be treated to avoid recurrence.

PRESENTATION OF CASE

A 38-year-old man with a medical history of chronic kidney failure was presented to the hospital for bilateral quadricipital tendon ruptures after a low-energy trauma. Ruptures were in the midportion of the tendon on the right side and in the level of patellar insertion on the left side. We performed a surgical reparation. One year after surgery, he consulted for a recurrence of the left quadricipital tendon rupture after an impeded extension movement. Biology showed secondary hyperparathyroidism due to chronic renal failure. Surgical reparation and reconstruction by a graft tendon were performed. As for his secondary hyperparathyroidism, he got a sub-parathyroidectomy after medical treatment failure. Recovery was remarkably uneventful.

DISCUSSION

Despite the early diagnosis and treatment of a bilateral quadricipital tendons rupture, our patient had an iterative rupture. His secondary hyperparathyroidism due to chronic renal failure may weaken the tendon system through physiological and histological modifications, as it is reported in the literature. As a result, treating a bilateral rupture as a banal post-traumatic lesion without management of the predisposing factors may lead to recurrences.

CONCLUSION

A non or low-traumatic tendon rupture in a patient with a history of chronic renal failure needs to identify secondary hyperparathyroidism, which must be treated to avoid recurrences.

An in-depth study on the magnetic resonance imaging characteristics of tendon rupture in sports injuries and its correlation with patients' clinical symptoms

Muscle injuries, such as Achilles and quadriceps tendon ruptures, pose a significant challenge in elite sports, accounting for more than 30% of all sports-related injuries. Our primary goal is to investigate the MR imaging characteristics of tendon rupture in sports injuries and their relationship with patients' clinical symptoms. In our retrospective study at Zhejiang University of Traditional Chinese Medicine's Second Affiliated Hospital (Zhejiang Xinhua Hospital), we compared the clinical presentation and MRI results of 106 patients with isolated AT and QT ruptures. In the AT, the enthesis was identified as a common site of bony avulsions (30.2%). In contrast, insertional ruptures were more common in the gastrocnemius heads (69.8% and 66.0%). The low frequency of mid-substance tears (13.2% to 20.8%) demonstrated the central tendon region's inherent tensile strength. The ruptured musculotendinous junctions affected the soleus (20.8%). In QT, bony avulsions play a minor role (5.1% to 11.3%). The patella was the primary site of tears (42.2% - 45.3%), with the Vastus intermedius favoring proximal tears (58.5%). Our examination of AT and QT ruptures across sub-components sheds light on their distinct patterns and the implications for clinical practice in terms of precise diagnosis, personalized treatment, and, ultimately, better patient outcomes for these debilitating injuries.

Extensor Mechanism Reconstruction for Chronic Patellar Tendon Tears

OBJECTIVES

Reconstruction for a chronic patellar tendon rupture in a native knee is an uncommon surgical procedure. Although there have been case series investigating patient-reported outcomes, there is no systematic review of these studies to date. The purpose of this review is to synthesize the literature on this procedure to better understand its outcomes, complications, and surgical technique options.

METHODS

A systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify studies that reported outcomes and techniques of patellar tendon reconstruction for chronic disruption in native knees. Searches were conducted through MEDLINE using PubMed, Cochrane Database of Systematic Reviews, and clinicaltrials.gov.

RESULTS

Ten studies with 103 patients and 105 knees were included. Results for nonnative (arthroplasty) knees were excluded. The mean patient age was 40.3 years, and the mean postsurgical follow-up time was 53.8 months. Of the 105 knees, 75% received a hamstring tendon graft, whereas 13% received a bone-tendon-bone graft and 7% received a whole extensor mechanism allograft. The mean preoperative range of motion was 113.8°, which improved to 126.0° postoperatively. The mean preoperative Lysholm score was 58.6, which improved to 86.0 postoperatively; 100% of patients returned to their normal work activities and 76% returned to their prior level of physical activity. There were no major complications reported in any of the included studies.

CONCLUSIONS

Chronic patellar tendon disruption in a native knee is an uncommon injury that can result in significant limitations for patients. Although more research is needed to better elucidate which graft is best, outcomes after patellar tendon reconstruction for chronic tears appear to be satisfactory with current techniques.

Complications and re-operations after extensor mechanism repair surgery in a large cross-sectional cohort: females and tobacco-users at highest risk for adverse outcomes

PURPOSE

There is little information on patients most at risk for poor outcomes following surgical repair of extensor mechanism tendon injuries. The purpose of this study is to provide an epidemiological overview of patients undergoing patellar or quadriceps tendon repair and to assess the incidence of postoperative complications, readmissions, and revision repairs among this population.

METHODS

Retrospective data were obtained using the PearlDiver database for patellar tendon repair and quadriceps tendon repair patients between 2010 and 2020. Baseline demographics, incidences of 90-day readmissions and postoperative complications, and reoperation rates were collected for each group. Multivariate logistic regression was performed to assess the predictive power of each demographic variable on the incidence of postoperative complications and reoperations.

RESULTS

In total, 1543 patients underwent patellar tendon repair and 601 underwent quadriceps tendon repair. Complications within 90-days were observed in 33.7% of patients with patellar tendon repair and 39.2% of patients with quadriceps tendon repair. Reoperation rates were 4.2% and 4.8% for patellar tendon repair and quadriceps tendon repair, respectively. Females in both patellar tendon repair and quadriceps tendon repair groups were at significantly higher risk for post-operative complications (patellar tendon repair OR 3.0, 95% CI 2.4-3.7; quadriceps tendon repair OR 2.9, 95% CI 1.9-4.6; p < 0.001 for both). Older age (p < 0.001), female gender (p < 0.001), CCI (p < 0.001), tobacco use (p < 0.001), and obesity (p < 0.01) were all predictors of experiencing at least one complication following patellar tendon repair. For quadriceps tendon repair, female gender (p < 0.001) and CCI (p < 0.001) were the strongest predictors of experiencing at least one complication, while older age, tobacco use, and obesity (p < 0.05 for all) were also significant independent predictors.

CONCLUSION

Patellar tendon repair patients are younger on average than quadriceps tendon repair patients. Although females are less likely to sustain extensor mechanism ruptures compared to males, females are significantly more likely to have at least one complication after quadriceps or patellar tendon repair. These findings may be used by surgeons, patients, and payors to understand who is most at risk for adverse outcomes following extensor mechanism repair surgery, resulting in earlier intervention and counseling to reduce the likelihood of a poor outcome following extensor mechanism repair surgery.

LEVEL OF EVIDENCE

Level III.

Bilateral Chronic Quadriceps Tendon Ruptures Treated with Hamstring Autograft Reconstruction: A Case Report

CASE

A 30-year-old semiprofessional football player presented with chronic bilateral quadriceps tendon ruptures. Both quadriceps tendon ruptures were unsuitable for isolated primary repair because of tendon retraction and immobility. A novel reconstruction technique using semitendinosus and gracilis tendon autografts was performed to restore both lower extremities' disrupted extensor mechanisms. At the final follow-up, the patient regained excellent motion of both knees and returned to high-intensity activity.

CONCLUSION

Chronic quadriceps tendon ruptures present challenges related to tendon quality and mobilization. Reconstruction with hamstring autograft using a Pulvertaft weave through the retracted quadriceps tendon in a high-demand athletic patient represents a novel approach for treating this injury.

Quadriceps Tendon Reconstruction With Achilles Tendon Bone Block Allograft

Chronic quadriceps tendon ruptures are relatively uncommon albeit debilitating injuries to the knee extensor mechanism. Previous literature demonstrates worse reported outcomes with delayed surgical intervention, and no gold-standard technique currently exists for managing chronic quadriceps tendon ruptures. The goal of this technique is to provide orthopaedic surgeons an additional option that may provide a greater mechanical load to failure and greater allograft acceptance for cases with large tendon gapping or poor tissue quality that may not be viable to other lengthening techniques. We describe the repair of a chronic quadriceps tendon rupture using an Achilles tendon bone block allograft.

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.

Clinical Outcomes are Similar Between Graft Types Used in Chronic Patellar Tendon Reconstruction: A Systematic Review

Purpose

To compare clinical outcomes between graft types and techniques used to repair chronic patellar tendon injuries to help surgeons make evidence-based decisions.

Methods

Medline, Embase, and Cochrane libraries were searched through January 2021, according to Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. Inclusion criteria were surgical treatment of chronic patellar tendon injury (defined as >6 weeks old), article available in English, and human subjects, minimum 1-year follow-up, and level of evidence I-IV. Studies describing chronic patellar tendon ruptures in the setting of total knee arthroplasty were excluded. Study quality was assessed using the Joanna Briggs Institute Critical Appraisal tools for case reports and case series.

Results

A total of 642 studies were identified through the initial search with 9 studies meeting all inclusion criteria. All studies included were case series encompassing 96 patients with follow-up ranging from 21 months to 7.2 years. Reconstruction techniques included the use of semitendinosus and/or gracilis tendon(s), Achilles tendon, bone-patellar tendon-bone (BTB), or direct repair. The most common graft choice was semitendinosus and/or gracilis tendon(s). Each reconstruction method yielded improvement in respect to range of motion (ROM), extensor lag, quadriceps strength, and patient-reported outcome measures (PROMs). Commonly reported complications were pain and numbness with only one reported instance of graft failure.

Conclusions

In this study, we found that all reconstructive methods described in the literature can produce satisfactory outcomes with improved function, strength, and minimal complications after chronic patellar tendon ruptures. Because of study heterogeneity and low levels of evidence, consensus cannot be reached on a single superior reconstruction method.

Level of Evidence

Level IV, systematic review of level IV studies.

Using Nonlinear Vibroartrographic Parameters for Age-Related Changes Assessment in Knee Arthrokinematics

Changes in articular surfaces can be associated with the aging process and as such may lead to quantitative and qualitative impairment of joint motion. This study is aiming to evaluate the age-related quality of the knee joint arthrokinematic motion using nonlinear parameters of the vibroarthrographic (VAG) signal. To analyse the age-related quality of the patellofemoral joint (PFJ), motion vibroarthrography was used. The data that were subject to analysis represent 220 participants divided into five age groups. The VAG signals were acquired during flexion/extension knee motion and described with the following nonlinear parameters: recurrence rate (RR) and multi-scale entropy (MSE). RR and MSE decrease almost in a linear way with age (main effects of group p<0.001; means (SD): RR=0.101(0.057)−0.020(0.017); and MSE=20.9(8.56)−13.6(6.24)). The RR post-hoc analysis showed that there were statistically significant differences (p<0.01) in all comparisons with the exception of the 5th−6th life decade. For MSE, statistically significant differences (p<0.01) occurred for: 3rd−7th, 4th−7th, 5th−7th and 6th life decades. Our results imply that degenerative age-related changes are associated with lower repeatability, greater heterogeneity in state space dynamics, and greater regularity in the time domain of VAG signal. In comparison with linear VAG measures, our results provide additional information about the nature of changes of the vibration dynamics of PFJ motion with age.

Modified Pulvertaft on Weave Technique Restores Full Active Knee Extension in Patients With Large Chronic Quadriceps Tendon Rupture: A Case Series

PURPOSE

We aimed to investigate the clinical and functional outcomes, including maximal and explosive strength, after chronic quadriceps tendon rupture repair with Modified Pulvertaft on Weave (MPW) technique METHODS: Knee joint range of motion (ROM), patella height, thigh circumference, and Lysholm and International Knee Documentation Committee (IKDC) scores were assessed preoperatively and postoperatively. The knee extensors maximal (isokinetic peak torque and isometric maximal voluntary contraction (MVC) torque) and explosive strength-rate of torque development (RTD) early [RTD₅₀ and RTD₁₀₀] and late [RTD₂₅₀]-were performed. We assessed the thigh circumference and vastus lateralis muscle thickness (MT) as indicators of quadriceps muscle mass, and the voluntary quadriceps activation using surface electromyography (EMG₅₀).

RESULTS

Nine patients (mean age: 53 ± 11 years) took part in the study. We observed a significant increase in the knee active ROM and a decreased extension deficit (both, P < .001), but not for pain (P = .07), IKDC (P = .07), and Lysholm (P = .21) after the surgery. We did not observe a difference between involved (n = 8) and uninvolved (n = 10) limbs for ROM, thigh circumference, and MT. We observed differences for extensors peak torque, MVC torque, and late RTD (all, P < .05). However, we did not observe differences for early RTD and EMG₅₀. Significant positive correlations were observed for RTD₅₀ (ρ = .80) and RTD₁₀₀ (ρ = .81) vs EMG₅₀. Both the IKDC and Lysholm were better correlated with the early than with later RTD.

CONCLUSIONS

The MPW reestablished the active knee extension. The same level of quadriceps muscle mass was observed in both limbs, suggesting a lack of hypotrophy due to the injury. Although the involved limb had demonstrated lower knee extensors maximal strength, they demonstrate an equivalent early RTD when compared to the uninvolved limb. The early RTD seems to be better correlated with the patient's functionality than the later RTD and maximal strength.

LEVEL OF EVIDENCE

IV, case series.

Review of Extensor Mechanism Injuries in the Dislocated Knee

Knee dislocations, aka multiligamentous injuries, are uncommon but devastating injuries often following high-energy trauma. Tears of the major knee stabilizers are well documented; however, injuries of the knee extensor mechanism are less commonly reported. The extensor mechanism is comprised of the patella, patellar tendon, and quadriceps tendons. Magnetic resonance imaging (MRI) is the preferred imaging modality of internal derangements of the knee due to its excellent soft tissue contrast. In this article, we will discuss the normal imaging findings of the extensor mechanism and review abnormalities following knee dislocation.

Extensor Mechanism Ruptures and Reruptures: Perioperative Opioid Management

The purpose of this study was to determine (1) the correlation between preoperative and postoperative opioid use and (2) risk factors associated with rerupture in patients undergoing open extensor mechanism repair. A retrospective review of patients who underwent operative repair of quadriceps or patellar tendon rupture was performed. Patients were classified as opioid nonusers if they had not received any opioid medications in the 3 months before surgery, or as acute users or chronic users if they received at least one opioid prescription within 1 month or 3 months preceding surgery. Clinical records were reviewed for postoperative opioid use within a year after surgery as well as rerupture rates. A total of 144 quadriceps tendon and 15 patellar tendon repairs were performed at a mean age of 56.8 ± 15.1 years and body mass index of 33.2 ± 7.1. The overall rerupture rate was 6%. Diabetes was a significant risk factor for rerupture (56 vs. 19%, p = 0.023). Chronic preoperative opioid users were more likely to continue to use opioids beyond 1 month postoperatively (p < 0.001) as compared with acute or nonopioid users. Chronic preoperative opioid users (relative risk [RR]: 3.53, 95% confidence interval [CI]: 2.11-5.90) and patients with longer anesthesia time (RR: 1.39, 95% CI: 1.00-1.93) required more monthly opioid refills, whereas tourniquet use required fewer opioid refills each month (RR: 0.57, 95% CI: 0.37-0.88). Compared with patients without a rerupture, each additional prescription refill after the initial repair in the rerupture group was associated with a 22% higher risk of tendon rerupture (RR: 1.22, 95% CI: 1.07-1.39). The chronicity of preoperative opioid intake was found to have a significant effect on postoperative opioid use. This study suggests that there is a higher prevalence of rerupture in patients with prolonged opioid use postoperatively and among diabetics.

Quadriceps reconstruction with suture anchor and Achilles allograft combination in quadriceps tendon re-rupture after primary surgical repair: A novel technique

Quadriceps ruptures are one of the pathological conditions of the knee extensor mechanism, accounting for 3% of all tendon injuries. These injuries cause substantial disability of the extensor mechanism. Primary repair is the treatment of choice in acute presentation. In the setting of chronic conditions, the treatment becomes more challenging. Available surgical options include lengthening procedures, and reconstruction with auto graft or allografts. The traditional Scuderi and Codivilla techniques are challenging to perform in degenerative or traumatic retracted ruptures. There is no standard effective treatment in these patients, which yields the best clinical and biomechanical outcomes. An 18-year-old male patient with quadriceps re-rupture after a primary repair was managed with allograft reconstruction using suture anchors. At six years of follow-up, the patient gained a full range of motion with excellent clinical outcomes. He returned to his previous work. In conclusion, quadriceps reconstruction using suture anchor and Achilles allograft combination is a feasible technique in neglected cases who present with quadriceps tendon re-rupture after primary surgical repair.

Soft tissue extensor mechanism tendon ruptures of the knee

Ruptures of the extensor mechanism of the knee are serious injuries requiring prompt diagnosis and treatment. They can be divided into soft tissue and bony causes. Soft tissue tendon injuries can be either partial or complete. Rupture of the quadriceps tendon is an uncommon injury and is more frequent in patients over the age of 40 years. Patella tendon ruptures are even rarer and are more frequent in patients under the age of 40 years. Causes can be direct or indirect. Complete ruptures of the quadriceps tendon or patella tendon benefit from early surgical management, while partial ruptures may be managed non-operatively. This article gives an overview of the presentation, assessment and management of soft tissue extensor mechanism tendon ruptures for core surgical, acute care common stem and emergency medicine trainees.

Achilles Tendon Allograft with Semitendinosus Autograft Reinforcement Is a Successful Treatment for Chronic Patellar Tendon Rupture: Report of Two Cases

Rupture of the patellar tendon must be diagnosed urgently because reconstruction of the extensor mechanism produces better results when it is performed in acute conditions. Reconstruction of chronic extensor mechanism rupture on the contrary is very challenging. Several surgical techniques have been described using a variety of graft choices and fixation methods, but the optimal approach is still under debate. We report our experience of two cases of chronic patellar tendon rupture reconstruction using an Achilles tendon allograft reinforced by a vascularized ipsilateral semitendinosus tendon frame. The rapid functional recovery of the range of motion, only three months postoperatively, showed us that this reconstruction technique was effective.

Epidemiology of Acute Extensor Mechanism Injuries in Collegiate-Level Athletes in the United States

BACKGROUND

Extensor mechanism injuries involving the quadriceps tendon, patella, or patellar tendon can be a devastating setback for athletes. Despite the potential severity and relative frequency with which these injuries occur, large-scale epidemiological data on collegiate-level athletes are lacking.

STUDY DESIGN

Descriptive epidemiology study.

LEVEL OF EVIDENCE

Level 4.

METHODS

Knee extensor mechanism injuries across 16 sports among National Collegiate Athletic Association (NCAA) men and women during the 2004-2005 to 2013-2014 academic years were analyzed using the NCAA Injury Surveillance Program (NCAA-ISP). Extensor mechanism injuries per 100,000 athlete-exposures (AEs), operative rate, annual injury and reinjury rates, in-season status (pre-/regular/postseason), and time lost were compiled and calculated.

RESULTS

A total of 11,778,265 AEs were identified and included in the study. Overall, 1,748 extensor mechanism injuries were identified, with an injury rate (IR) of 14.84 (per 100,000 AEs). N = 114 (6.5%) injuries were classified as severe injuries with a relatively higher median time loss (44 days) and operative risk (18.42%). Male athletes had higher risk of season-ending injuries in both all (3.20% vs 0.89%, P < 0.01) and severe (41.54% vs 16.33%, P < 0.01) extensor mechanism injuries. Similarly, contact injuries were more frequently season-ending injuries (4.44% vs 1.69%, P = 0.01). Women's soccer (IR = 2.59), women's field hockey (IR = 2.15), and women's cross country (IR = 2.14) were the sports with the highest rate of severe extensor mechanism injuries.

CONCLUSION

Extensor mechanism injuries in collegiate athletes represent a significant set of injuries both in terms of volume and potentially to their athletic careers. Male athletes and contact injuries appear to have a greater risk of severe injuries. Injuries defined as severe had a higher risk of operative intervention and greater amount of missed playing time.

CLINICAL RELEVANCE

Knowledge of the epidemiology of extensor mechanism injuries may help clinicians guide their athlete patients in sports-related injury prevention and management.

MR imaging of the quadriceps femoris tendon: distal tear characterization and clinical significance of rupture types

Objective

To characterize quadriceps femoris tendon tears on magnetic resonance (MR) imaging regarding tear extent, location, and presence of bony avulsion.

Materials and methods

IRB approval was obtained and informed consent was waived for this retrospective case series. Electronic medical records from all patients in our hospital system were searched for keywords: knee MR imaging, and quadriceps tendon rupture or tear. MRI studies were randomized and independently evaluated by two fellowship-trained musculoskeletal radiologists. MR imaging was used to characterize each individual quadriceps tendon as having tendinosis, tear (location, partial versus complete, size, and retraction distance), and bony avulsion. Knee radiographs were reviewed for presence or absence of bony avulsion. Descriptive statistics and inter-reader reliability (Cohen’s Kappa and Wilcoxon-signed-rank test) were calculated.

Results

Fifty-two patients with 53 quadriceps tears were evaluated (45 males, 7 females; mean age: 51 ± 13 years). The vastus intermedius (VI) tendon more often incurred a partial rather than a complete tear (39.6% vs. 37.7%), while the rectus femoris (RF), vastus medialis (VM), and vastus lateralis (VL) incurred complete tears more commonly (64.2–66%). Subjects with bony avulsion on radiographs had higher-grade tears of the RF, VM, and VL tears (p = 0.020–0.043) but not the VI. Most tendons tore at or immediately proximal to the patella (84.8–93.6%). Gaps in retracted torn tendons measured between 2.3 and 2.7 cm. Inter-reader reliability was substantial to almost perfect (κ = 0.624–0.953).

Conclusion

Quadriceps femoris tendon tears most commonly involve the RF or VL/VM layers usually in proximity to the patella. A bony avulsion correlates with a more extensive tear.

Key Points

• Quadriceps femoris tendon tears most commonly involve the rectus femoris or vastus lateralis/vastus medialis layers.

• A rupture of the quadriceps femoris tendon usually occurs in proximity to the patella.

• A bony avulsion of the patella correlates with a more extensive tear of the superficial and middle layers of the quadriceps tendon.

Long-term follow up of extensor tendon ruptures of the knee using electromyography and three-dimensional gait analysis

BACKGROUND

The aim of this study was to analyze the long-term outcomes of extensor tendon ruptures of the knee using exact measuring tools.

METHODS

The results of patients treated for extensor tendon rupture with a minimum follow up of 10 years were reviewed. Electromyography (EMG) and three-dimensional (3D) gait analyses were performed and compared with the healthy side of each patient and with the gait patterns of 20 healthy controls. Functional outcome scores were assessed using the Lysholm score and Knee Injury and Osteoarthritis Outcome Score (KOOS).

RESULTS

After a mean of 13.4 ± 3 years, 23 patients were available for follow up. The mean Lysholm score was 86.6, and the KOOS averaged 78.1. Gait analysis showed no major kinematic differences between these patients compared with healthy controls. In the squat test, the mean peak amplitude of the rectus femoris muscle was significantly smaller on the injured side than on the healthy side (140.21 ± 66.13 μV vs. 168.25 ± 91.77 μV; P = 0.01). The mean peaks of the vastus lateralis and medialis EMG signals were also lower on the injured side (P = 0.63; P = 0.08). Correspondingly, the thigh girth at 20 cm and 10 cm above the knee was significantly lower on the injured side. One patient had re-rupture after patella tendon repair.

CONCLUSION

At long-term follow up the patients reached good clinical outcomes and exhibited mainly physiological gait patterns after rupture of knee extensor tendons. However, the thigh muscles showed hypotrophy and a significantly smaller EMG signal amplitude during a high-intensity task on the formerly injured side.

Functional Outcomes of Revision Osteosynthesis after Failure of Surgical Treatment of Patellar Fractures

Patellar fractures account for approximately 1% of all skeletal fractures. These fractures are rare; however, because of the crucial function of the patella in the extensor mechanism of the knee, they may lead to serious impairment. New data are revealing functional impairment remains common even with improved surgical techniques. The aim of this study was to assess the functional outcomes of patients after revision surgery in cases of secondary fracture dislocation or persistent articular incongruity. This study included 16 patients with a mean age of 51.8 years (range: 16-85 years) with a mean follow-up of 35.1 months. According to the AO/OTA classification, 15 patients had a C-type fracture, including 10 patients with C3 fracture. Thirteen patients were initially treated with tension band wiring via K-wires or cannulated screws. Revision surgery was performed because of persistent articular incongruity in five patients and secondary fracture dislocation or refracture in 11 patients. We analyzed pain (visual analog scale [0-10]), satisfaction, range of motion (ROM), Böstman's score, Lysholm's score, and knee injury and osteoarthritis outcome score (KOOS) after revision surgery and could extract follow-up data from 15 patients. Mean pain score at rest was 0.57 (range: 0-3.5) and on exertion 2.79 (range: 0-8). The measurement of the ROM of the affected knee compared with that of the opposite knee revealed complete extension. Mean flexion was 123 degrees, in the corresponding knee it was 136 degrees (p = 0.05). The mean postoperative Böstman's and Lysholm's scores were 25.11 (good, maximum: 30) and 78.67 (moderate, maximum: 100), respectively. KOOS was as follows: symptoms, 66.8 points; pain, 77.55 points; activity of daily living (ADL), 75.67 points; and quality of life, 56.25 points. The results of this study suggested that early revision surgery after failure of primary osteosynthesis with secondary anatomic reconstruction and good radiological results leads to satisfactory functional outcomes with persistent functional deficits.

Reconstruction of Chronic Patellar Tendon Injury with Achilles Tendon Allograft: A Case Report

CASE

There have been several methods described for the reconstruction of chronic patellar tendon injuries in the native knee. Here, we report a former athlete who sustained a tibial tubercle fracture as an adolescent and presented with functional deficits from a patellar tendon that healed in elongation after the removal of hardware and debridement of ossifications within the tendon. He underwent reconstruction with Achilles allograft.

CONCLUSIONS

Achilles tendon allograft is a good option for reconstructing chronic patellar tendon injuries. Our patient had an excellent outcome at 1 year.

Management of chronic quadriceps rupture with novel "chariot suture technique": A case report and review

Quadriceps tendon is one of the important segment of knee extensor mechanism. Acute ruptures are more common than chronic ruptures and have better outcomes. Chronic ruptures are rare with lot of surgical challenges including tendon retraction, fibrosis, degenerative calcification. We present a rare case of a 48 year old male diabetic patient with history of fall eight months ago and chief complaint of inability to actively extend his left knee. Diagnosis was made clinically and was confirmed radiologically with MRI. Surgical management was done with the use of novel "Chariot Suture Technique". It involves use of three Krakow whipstitches with Ethibond No. 5 suture across the distal ruptured end of quadriceps tendon and their intraosseous passage through patella in longitudinal fashion followed by tying knot at the distal pole of patella. The formation of Chariot makes the construct stable. At one year follow up patient was actively able to extend the knee with good range of motion. The technique is relatively cost effective, has no donor site morbidity, easy to learn and practice.

Point-of-care Ultrasound Diagnosis of Bilateral Patellar Tendon Rupture

Musculoskeletal complaints are one cornerstone of urgent issues for which orthopedic and emergency physicians provide care. Ultrasound can be a useful diagnostic tool to help identify musculoskeletal injuries. We describe a case of bilateral patellar tendon rupture that presented after minor trauma, and had the diagnosis confirmed at the bedside by point-of-care ultrasound. Physicians caring for patients with orthopedic injuries should be familiar with the use of ultrasound to diagnose tendon ruptures.

Surgical Treatment for Chronic Rupture of the Patellar Tendon Performed in 2 Stages

Patellar tendon rupture is an uncommon but disabling lesion. It usually occurs in men younger than 40 years, through direct or indirect trauma. Obtaining satisfactory results with treatment of chronic injuries and re-ruptures in which the patella retracts owing to quadriceps contraction is a challenge. This is of major concern especially in cases in which the patella cannot be positioned in its anatomic position when distal traction is performed. In these cases, V-Y stretching of the quadriceps can be performed in an attempt to perform reconstruction in 1 stage. Instead, a 2-stage procedure can be chosen, in which the first stage relies on patellar trans-skeletal traction to achieve distalization of the patella. In 1981, a technique for the treatment of chronic injuries of the patellar tendon in 2 stages was described. In that procedure, the first stage consisted of transpatellar traction and the second stage was tendon-tendon suturing with fascia lata reinforcement. We describe a surgical technique performed in 2 stages; in the first stage, trans-skeletal traction is performed, and in the second stage, the technique of Kelikian et al. with our modification is performed. This technique is used in patients with chronic rupture of the patellar tendon associated with a high patella with nonreducible quadriceps shortening.

Surgical Treatment of Chronic Rupture of the Quadriceps Using a Modified Pulvertaft Weave Technique

The extensor mechanism provides active knee joint extension and stability of the patellofemoral joint. Rupture of the quadriceps tendon, although uncommon, is therefore associated with impairment in knee joint stability and, thus, requires surgical repair. Although various techniques provide excellent clinical outcomes for acute rupture, treatment of chronic rupture remains clinically challenging. We describe our modified technique for quadriceps tendon repair using a semitendinosus tendon autograft, with suturing of the quadriceps tendon stump to the patella via transosseous sutures, wherein the use of allograft and anchors is avoided. Our modified Pulvertaft weave technique is simple and reproducible.

Semitendinosus autograft augmentation after bilateral patellar tendon re-rupture: a case report and technique note

BACKGROUND

Acute bilateral patellar tendon rupture is a rare occurrence, especially in young patients in the absence of comorbidities. We describe a case of bilateral patellar tendon re-rupture in a young patient without predisposing factors. Further, we explain a technique for autograft augmented patellar tendon repair with bidirectional fixation using an ipsilateral semitendinosus graft in transosseous patellar and tibia bone tunnels.

CASE PRESENTATION

We present the case of a 40-year-old healthy worker with bilateral acute on chronic patellar tendon rupture maintained following initial trauma and Krackow repair 2 years ago. He underwent bilateral reconstruction using semitendinosus autograft. At 1 year postoperatively, he has maintained the full range of motion and strength without re-rupture.

CONCLUSION

This is the first case describing a new fixation technique after bilateral patellar tendon re-rupture. The use of semitendinosus autograft for reconstruction of the patellar tendon after re-rupture is a viable and effective option.

Ultrasound anatomy of the normal stifle in the sheep

Though the ovine stifle is commonly used as a model in research, there is no description of its anatomy at ultrasonography (US). The objective of this study was to provide reference US images of the ovine stifle that are relevant in musculoskeletal research. Four pairs of hindlimbs were scanned, whilst four other pairs were frozen and cut in different planes to compare gross anatomy to US scans. In another pair, the synovial compartments of the stifle were injected and scanned. This study demonstrated that US could be used to assess the ovine stifle. Several structures of clinical interest could be identified with cranial, lateral and medial approaches, such as (a) the tendons of m. quadriceps femoris, m. gluteobiceps, m. popliteus, (b) the common tendon of m. peroneus tertius-extensor longus digitorum-extensor digiti III proprius, (c) the patellar ligament, (d) the medial and lateral collateral ligaments, (e) the cranial horn and middle segment of medial and lateral meniscus, and (f) the synovial recesses. However, the caudal approach was not successful to identify caudal anatomical structures of the joint, due to the muscular mass, that is the caudal aspects of the articular surfaces of the femoral and tibial condyles, the caudal horns of the menisci and the supracondylar synovial recesses. In addition, US remained challenging to assess the internal structures such as cruciate ligaments and articular surfaces. The feasibility of US needs to be tested in vivo.

Management of Simultaneous Patellar Tendon and Anterior Cruciate Ligament Ruptures-A Systematic Review of Available Literature

BACKGROUND

Combined rupture of the anterior cruciate ligament (ACL) and patellar tendon (PT) is a rare injury pattern. Currently, little evidence exists to help guide management decisions for these patients.

METHODS

A systematic literature search was conducted using PubMed (MEDLINE) and Scopus (EMBASE and MEDLINE) for all articles reporting on combined rupture of the ACL and PT. The characteristic injury mechanisms, common presentation findings, and outcomes of simultaneous and staged treatment strategies were determined to provide guidance for the management of this uncommon injury pattern. An additional case report from our institution is also reported.

RESULTS

Overall, 17 studies met the inclusion criteria and were included in our qualitative review. The mean age at injury was 30 years (range, 15-50 years). A high-energy injury with a rapid deceleration event through a flexed knee on a fixed foot is commonly described as the mechanism of injury. Anterior cruciate ligament rupture was missed on initial clinical examination in 24.1% compared with 17.2% for PT rupture. Injuries to the medial collateral ligament and menisci occured in 65.5% of cases. Outcome scores were reported in 41.4% (12/22) of patients undergoing staged or simultaneous repair. The Lysholm score postoperatively was 96 ± 3.3 for the staged group compared with 85.3 ± 18.6 for simultaneous repair. There were no clear differences between range of motion, time to return to sport, and complication rates between the groups.

CONCLUSIONS

A high index of suspicion is required to detect concomitant ACL injuries when assessing high-energy PT ruptures. Simultaneous or staged protocols to address both injuries are safe and effective management strategies for this rare combined injury pattern.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Imaging of patellar fractures

Patellar fractures account for approximately 1% of all skeletal fractures and may result from direct, indirect, or combined trauma. Because of the importance of patellar integrity for knee extension and the risk of associated injury to the extensor mechanism, accurate reporting and description of fracture type is paramount for appropriate management. This pictorial essay aims to review the normal anatomy of the patella, the mechanisms of injury and different types of patellar fractures, with a brief introduction to therapeutic management.

Teaching Points

• Patellar fractures are classified according to their morphology and degree of displacement.

• Direct trauma results in stellate fractures.

• Indirect trauma results in transverse fractures.

• Displacement should raise suspicion for retinacular injury.