Acute quadriceps tendon ruptures: a series of 50 knees with an average follow-up of more than 6 years

Risk Factors Associated With Poor Outcomes After Quadriceps Tendon Repair

Background

Ruptures of the quadriceps tendon present most frequently in older adults and individuals with underlying medical conditions.

Purpose

To examine the relationship between patient-specific factors and tear characteristics with outcomes after quadriceps tendon repair.

Study Design

Case-control study; Level of evidence, 3.

Methods

A retrospective review was conducted on all patients who underwent quadriceps tendon repair between January 1, 2016, and January 1, 2021, at a single institution. Patients <18 years and those with chronic quadriceps tendon tears (>6 weeks to surgery) were excluded. Information was collected regarding patient characteristics, presenting symptoms, tear characteristics, physical examination findings, and postoperative outcomes. Poor outcome was defined as a need for revision surgery, complications, postoperative range of motion of (ROM) <110° of knee flexion, and extensor lag of >5°.

Results

A total of 191 patients met the inclusion criteria. Patients were aged 58.5 ± 13.2 years at the time of surgery, were predominantly men (90.6%), and had a mean body mass index (BMI) of 32.2 ± 6.3 kg/m2. Patients underwent repair with either suture anchors (15.2%) or transosseous tunnels (84.8%). Postoperatively, 18.5% of patients experienced knee flexion ROM of <110°, 11.3% experienced extensor lag of >5°, 8.5% had complications, and 3.2% underwent revision. Increasing age (odds ratio [OR], 1.03 [95% CI, 1.004-1.07]) and female sex (OR, 3.82 [95% CI, 1.25-11.28]) were significantly associated with postoperative knee flexion of <110°, and increasing age (OR, 1.08 [95% CI, 1.04-1.14]) and greater BMI (OR, 1.14 [95% CI, 1.05-1.23]) were significantly associated with postoperative extensor lag of >5°. Current smoking status (OR, 15.44 [95% CI, 3.97-65.90]) and concomitant retinacular tears (OR, 9.62 (95% CI, 1.67-184.14]) were associated with postoperative complications, and increasing age (OR, 1.05 [95% CI, 1.02-1.08]) and greater BMI (OR, 1.08 [95% CI, 1.02-1.14]) were associated with risk of acquiring any poor outcome criteria.

Conclusion

Patient-specific characteristics-such as increasing age, greater BMI, female sex, retinacular involvement, and current smoking status-were found to be risk factors for poor outcomes after quadriceps tendon repair. Further studies are needed to identify potentially modifiable risk factors that can be used to set patient expectations and improve outcomes.

Similar Outcomes Are Found Between Quadriceps Tendon Repair With Transosseous Tunnels and Suture Anchors: A Systematic Review and Meta-Analysis

Purpose

To evaluate the clinical outcomes and biomechanical performance of transosseous tunnels compared with suture anchors for quadriceps tendon repair.

Methods

In accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a systematic search was performed in April 2021 in the following databases: Cochrane Database of Systematic Reviews, PubMed (1980-2021), MEDLINE (1980-2021), Embase (1980-2021), and CINAHL (1980-2021). Level I-IV studies were included if they provided outcome data for surgical repair of the quadriceps tendon using transosseous tunnels or suture anchors with minimum 1-year follow-up. Biomechanical studies comparing transosseous tunnels and suture anchors were separately analyzed.

Results

The systematic search yielded 1,837 citations, 23 of which met inclusion criteria (18 clinical, 5 biomechanical). In total, 13 studies reported results for transosseous repair and 7 studies reported results for repair with suture anchors. There were results for 508 patients from clinical studies. The average postoperative Lysholm score ranged from 88 to 92 for suture anchor repairs and 72.8 to 94 for transosseous repairs with range of motion ranging from 117° to 138° and 116° to 135°, respectively. Synthesis of the biomechanical data revealed the mean difference in load to failure was not significant between constructs (137.21; 95% confidence interval -10.14 to 284.57 N; P = .068).

Conclusions

Transosseous and suture anchor techniques for quadriceps tendon repair result in similar biomechanical and postoperative outcomes. No difference between techniques in regard to ultimate load to failure among comparative biomechanical studies were observed.

Level of Evidence

Level IV, systematic review level III-IV studies.

Simultaneous bilateral quadriceps tendon rupture in a healthy young male: a case report

BACKGROUND

Simultaneous bilateral quadriceps tendon rupture is rare, particularly in young individuals with no prior medical history. We present the case of a young man who presented with bilateral quadriceps tendon rupture.

CASE PRESENTATION

A 27-year-old Japanese man missed a step while descending a flight of stairs, stumbled, and became aware of severe pain in both knees. He had no past medical history, but was severely obese, with a body mass index of 43.7 kg/m² (height 177 cm, weight 137 kg). Five days after injury, he was referred to our hospital for examination and treatment. Bilateral quadriceps tendon rupture was diagnosed based on magnetic resonance imaging, and quadriceps tendon repair with suture anchor was performed on both knees 14 days after injury. The postoperative rehabilitation protocol was to immobilize both knees in extension for 2 weeks, then to gradually proceed with weight-bearing and gait training using hinged knee braces. Both knees obtained a range of motion from 0° to 130° without any extension lag by 3 months postoperatively. One year postoperatively, tenderness was evident at the suture anchor in the right knee. That suture anchor was therefore removed in a second operation, and histological evaluation of the tendon of the right knee revealed no pathological changes. As of 19 months after the primary surgery, the patient showed a range of motion from 0° to 140° in both knees, did not complain of any disability, and had fully returned to normal daily activities.

CONCLUSIONS

We experienced simultaneous bilateral quadriceps tendon rupture in a 27-year-old man with no past medical history other than obesity. Suture anchor repair was performed for both quadriceps tendon ruptures and achieved a favorable postoperative outcome.

Quadriceps Tendon Ruptures in Middle-Aged to Older Patients: A Retrospective Study on the Preoperative MRI Injury Patterns and Mid-Term Patient-Reported Outcome Measures

(1) Quadriceps tendon rupture (QTR) is a rare pathology, usually occurring in elderly patients with comorbidities, requiring surgical therapy. The aim of this study was to analyze rupture patterns and concomitant injuries using preoperative magnetic resonance imaging (MRI) and to evaluate patient-reported outcome measures. (2) In this retrospective cross-sectional study, 113 patients with QTR were screened and rupture patterns/concomitant injuries (n = 33) were analyzed via MRI. Clinical outcome was assessed in 45 patients using the International Knee Documentation (IKDC) and Lysholm score with a mean follow-up of 7.2 (±5.0) years. (3) The evaluation of preoperative MRIs showed multiple ruptures of subtendons in 67% with concomitant knee injuries in 45%. The most common associated pathology detected using MRI was pre-existing tendinosis (31.2%). Surgical refixation demonstrated good results with a mean post-operative IKDC score of 73.1 (±14.1) and mean Lysholm score of 84.2 (±16.1). Patient characteristics and individual radiologic rupture patterns did not significantly affect the clinical outcome of patients. (4) Acute QTRs are complex injuries with common involvement of multiple subtendons. MRI imaging can be useful for achieving an accurate diagnosis as pre-existing tendinosis as well as concomitant injuries are common, and might be useful for providing an individual surgical strategy and improving outcomes.

Transosseous Repair With Nice Knot Augmentation Versus Knotless Suture Anchor Repair With Suture Tape for Quadriceps Tendon Rupture: A Cadaveric Study

Quadriceps tendon rupture is typically repaired using either transosseous tunnels or suture anchors. Recent literature has suggested that suture anchor repair is biomechanically superior to the use of transosseous tunnels. Augmentation of the transosseous technique with Nice knots may result in improved biomechanical properties as compared with a suture anchor construct. To compare biomechanical properties of a novel transosseous quadriceps tendon repair technique with Nice knot augmentation to those of knotless suture anchor repair, an artificial quadriceps tendon rupture was created in 10 matched pairs of cadaveric knees (n=20). Each cadaver was subjected to biomechanical testing to calculate the average ultimate load to failure, repair site gapping after early and late cyclic loading, and stiffness. Transosseous repair augmented with Nice knots as compared with knotless suture anchor repair had greater load to failure (mean±SD, 1489.5±297.6 N vs 717.7±191.4 N, P<.001), decreased gapping after early and late cyclic loading (cycles 1-20: mean±SD, 0.59±0.4 mm vs 2.1±1.2 mm, P=.008; cycles 21-250: mean±SD, 1.2±0.7 mm vs 3.9±1.7 mm, P=.002), and greater construct stiffness (mean±SD, 80.7±15.7 N/mm vs 44.4±13.4 N/mm, P=.001). The transosseous quadriceps tendon repair technique with Nice knot augmentation is biomechanically better than knotless suture anchor repair with regard to ultimate load to failure, gap formation after cyclic loading, and construct stiffness in cadaveric specimens. [Orthopedics. 202x;4x(x):xx-xx.].

Risk Factors for Infection and Revision Surgery following Patellar Tendon and Quadriceps Tendon Repairs: An Analysis of 3,442 Patients

Disruption of the extensor mechanism is debilitating with surgical repair being the accepted treatment. The incidence of infection and reoperation after extensor mechanism repair are not well reported in the literature. Thus, the objective of the current study was to (1) determine the incidence of surgical site infection and reoperation within 1 year of primary extensor mechanism repair and (2) identify independent risk factors for infection and reoperation following patellar and quadriceps tendon repair. A retrospective review of the 100% Medicare Standard Analytic files from 2005 to 2014 was performed to identify patients undergoing isolated patellar tendon repair and quadriceps tendon repair. Diagnosis of infection within 1 year of operative intervention and revision repair were assessed. Extensor mechanism injuries in the setting of total knee arthroplasty and polytrauma were excluded. Multivariate logistic regression analysis was performed to evaluate risk factors for postoperative infection and reoperation within 1 year. Infection occurred in 6.3% of patients undergoing patellar tendon repair and 2.6% of patients undergoing quadriceps tendon repair. Diabetes mellitus (odds ratio [OR] = 1.89, p = 0.005) was found to be an independent risk factor for infection following patellar tendon repair. Reoperation within 1 year occurred in 1.3 and 3.9% following patellar tendon and quadriceps tendon repair, respectively. Age less than 65 years (OR = 2.77, p = 0.024) and obesity (OR = 3.66, p = 0.046) were significant risk factors for reoperation after patellar tendon repair. Hypertension (OR = 2.13, p = 0.034), hypothyroidism (OR = 2.01, p = 0.010), and depression (OR = 2.41, p = 0.005) were significant risk factors for reoperation after quadriceps tendon repair. Diabetes mellitus was identified as a risk factor for infection after patellar tendon repair. Age less than 65 years, peripheral vascular disease, and congestive heart failure were risk factors for infection after quadriceps tendon repair. The current findings can be utilized to counsel patients regarding preoperative risk factors for postoperative complications prior to surgical intervention for extensor mechanism injuries.

Smaller Gap Formation With Suture Anchor Fixation Than Traditional Transpatellar Sutures in Patella and Quadriceps Tendon Rupture: A Systematic Review

PURPOSE

The purpose of this study is to compare the biomechanical properties between traditional transosseous tunnel and suture anchor technique repair for extensor mechanism ruptures and assess for differences in the mechanism of failure of both techniques.

METHODS

A multi-database search (PubMed, EMBASE, and Medline) was performed according to PRISMA guidelines on November 14, 2021. All articles comparing biomechanical properties of transpatellar and suture anchor technique for extensor mechanism ruptures were included. Abstracts, reviews, case reports, studies without biomechanical analysis, conference proceedings, and non-English language studies were excluded. Outcomes pursued included gap formation, load to failure, and mechanism of failure. Relevant data from studies meeting inclusion criteria were extracted and analyzed. Study methodology was assessed using the Methodological Index for Non-Randomized Studies score.

RESULTS

A total of 212 knees were biomechanically assessed, including 98 patella and 114 quadricep tendon ruptures. Five patellar tendon studies were included, and all of them reported significantly smaller gap formation in suture anchor group. Gap formation for suture anchors ranged from .9 mm to 4.1 mm, while that of transpatellar group ranged from 2.9 mm to 10.3 mm. One study reported a significantly higher load to failure in the suture anchor group, while the remaining four studies reported no significant difference. Load to failure for suture anchor ranged from 259 N to 779 N, while that of the transpatellar group ranged from 287 N to 763 N. The most common mechanism of failure was anchor pullout in suture anchor and knot failure in the transpatellar group. Five quadriceps tendon studies were included, and three studies reported statistically significant smaller gap formation in the suture anchor group. Gap formation for suture anchor ranged from 1.5 mm to 5.0 mm, while that of transpatellar group ranged from 3.1 mm to 33.3 mm. Two studies reported a significantly higher load to failure in the suture anchor group, while one study reported a higher load to failure in the transpatellar repair group. Load to failure for suture anchor ranged from 286 N to 740 N, while that of transpatellar group ranged from 251 N to 691 N. The most common mechanism of failure was suture failure in the suture anchor and knot failure in the transpatellar group.

CONCLUSION

Suture anchor fixation displays a better biomechanical profile than traditional transpatellar techniques in terms of smaller gap formations in the repair of both patella and quadriceps tendon injuries. Anchor pullout in suture anchor fixation was present mainly with the use of titanium anchors.

CLINICAL RELEVANCE

These findings above may result in better retention of tendon approximation in patella and quadriceps tendon fixation postoperatively, which may result in earlier recovery. Further randomized controlled clinical trials to compare these techniques are required.

Outcomes After Repair of Quadriceps Tendon Rupture in Patients Aged 40 Years and Younger

Background:

Injury to the quadriceps tendon is rare and most commonly occurs in middle-aged men. Few reports are available regarding outcomes after quadriceps tendon rupture in younger patients.

Purpose/Hypothesis:

To review the clinical outcomes of patients who underwent quadriceps tendon repair at age ≤40 years. We hypothesized that this cohort would experience better clinical outcomes in comparison to historical older controls.

Study Design:

Case series; Level of evidence, 4.

Methods:

Using an institutional database, we retrospectively identified patients who underwent quadriceps tendon repair between January 2009 and December 2017. Patients were included in the study if they were aged ≤40 years at the time of surgery and had sustained an isolated, complete tendon rupture. Patient and injury characteristics were recorded. Patients were contacted to complete a custom survey, the 2000 International Knee Documentation Committee (IKDC) form, the Lysholm scale, and the Tegner scale.

Results:

Included were 38 patients (86.8% male; mean age, 32.0 ± 6.9 years; age range, 15-40 years), with a mean follow-up of 5.9 ± 2.3 years (range, 2.4-11.3 years). At final follow-up, the mean IKDC score was 74.1 ± 22.6 (range, 26.4-100.0), and the mean Lysholm score was 85.4 ± 20.0 (range, 30-100), which were similar if not inferior to historical controls of patients >40 years. Only 16 patients (42.1%) had unchanged or higher Tegner scores after surgery, whereas 22 patients (57.9%) reported lower postoperative activity level. Overall, 91.2% (31/34) of workers returned at a mean 3.9 months after surgery, whereas 63% (12/19) of athletes were able to return to play at 8.8 months. At final follow-up, 12 patients (31.6%) reported persistent pain and stiffness in their knees. Additionally, 3 patients (7.9%) reported pain without stiffness, and 4 (10.5%) reported stiffness without pain. Patients reporting pain or stiffness had significantly lower IKDC scores, Lysholm scores, postoperative Tegner scores, and change in their Tegner score at final follow-up in comparison to those who did not report pain or stiffness.

Conclusion:

Although patients aged ≤40 years had satisfactory outcomes after quadriceps tendon repair, this injury resulted in significant long-term sequelae in a substantial percentage of patients, despite their youth. Further, this group did not have better outcomes compared with historical controls aged > 40 years.

A Survey of Treatment Trends for Acute Quadriceps Tendon Ruptures Among North American Surgeons

Background:

To date, little clinical evidence exists to support a specific surgical technique or postoperative rehabilitation protocol for quadriceps tendon ruptures. With a lack of evidence-based superiority, assessment of clinical practices and surgeon preferences is pertinent.

Purpose:

To describe the current surgical technique and rehabilitation preferences among members of the Canadian Orthopaedic Association and American Orthopaedic Society for Sports Medicine pertaining to acute quadriceps tendon rupture.

Study Design:

Cross-sectional study.

Methods:

Orthopaedic staff members of the Canadian Orthopaedic Association and American Orthopaedic Society for Sports Medicine were invited to complete an internet-based survey composed of 26 questions assessing current trends in the management and rehabilitation of acute quadriceps tendon rupture. Survey questions were developed after a thorough review of current literature. Survey responses were analyzed and reported using descriptive statistics (absolute values, frequencies, and percentages) where appropriate. Statistical comparisons and contrasts between Canadian and American surgeons were made using chi-square analyses and Student t tests.

Results:

A total of 264 surgeons participated in the survey (136 Canadians; 128 Americans). Canadian surgeons were more likely to obtain a preoperative ultrasound as compared with Americans (43.0% vs 6.7%; P < .00001), while American respondents were more likely to obtain magnetic resonance imaging scans (65.8% vs 10.2%; P < .00001). The transosseous drill hole technique was the most commonly utilized (70.2%); the suture anchor technique was used 20.6% of the time. Canadian respondents trended toward a higher use of transosseous tunnels; however, this was not statistically significant (75.8% vs 64.2%; P = .068). American respondents were more likely to utilize suture anchors (27.5% vs 14.1%; P = .0096). Most respondents advanced range of motion goals stepwise in 2-week intervals of 30° (Canadians, 54.0% vs Americans, 58.5%; P = .3091); timing of range of motion initiation varied.

Conclusion:

Among North American surgeons who responded to this study, the transosseous technique was the most commonly used, and range of motion was generally advanced in a 2-week stepwise fashion. We found several differences in practice between Canadian and American respondents, including the type of preoperative imaging and the frequency of using the suture anchor technique.

Midterm outcome and strength assessment after quadriceps tendon refixation with suture anchors

PURPOSE

Quadriceps tendon ruptures (QTR) occur predominantly in middle-aged patients through violent eccentric contraction that occurs either when trying to regain balance or during a fall on the hyperflexed knee. The aim of this study was to quantify midterm postoperative results, including strength potential measured via standardized strength tests following acute (< six weeks) quadriceps tendon refixation using suture anchors.

METHODS

All consecutive patients with QTR who underwent surgical suture anchor refixation between 2012 and 2019 at a single institution with a minimum follow-up of 12 months were retrospectively evaluated. Outcome measures included Tegner Activity Scale (TAS), Lysholm score, International Knee Documentation Committee subjective knee form (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS) subscales, return to work rates, and Visual Analog Scale (VAS) for pain. Additionally, a standardized clinical examination and an isometric strength assessment of knee extension and flexion were performed.

RESULTS

A total of 17 patients (median age 61.0 [25-75% IQR 50.5-72.5]) were available for final assessment at a mean follow-up of 47.1 ± SD 25.4 months. The majority of patients were male (82.4%) and most injuries occurred due to a fall on the hyperflexed knee (76.5%). The average time interval between trauma and surgery was 12.7 ± 7.5 days. Patients achieved a moderate level of activity postoperatively with a median TAS of 4 (3-5.5) and reported good to excellent outcome scores (Lysholm score: 97 (86.5-100); IKDC: 80.7 ± 13.5; KOOS subscales: pain 97.2 (93.1-100), symptoms 92.9 (82.5-100), activities of daily living 97.1 (93.4-100), sport and recreation function 80 (40-97.5) and knee-related quality of life 87.5 (62.5-100). All patients were able to fully return to work and reported little pain [VAS: 0 (0-0)]. No postoperative complications were reported. Strength measurements revealed a significant deficit of knee extension strength in comparison to the contralateral side (p = 0.011).

CONCLUSION

Suture anchor refixation of acute QTR leads to good functional results and high patient satisfaction without major complications. Isometric knee extension strength, however, may not be fully restored compared to the unaffected side.

Biomechanical Testing of Suture Anchor Versus Transosseous Tunnel Technique for Quadriceps Tendon Repair Yields Similar Outcomes: A Systematic Review

Purpose

To systematically review the literature to evaluate the biomechanical properties of the suture anchor (SA) versus transosseous tunnel (TO) techniques for quadriceps tendon (QT) repair.

Methods

A systematic review was performed by searching PubMed, the Cochrane Library, and Embase using PRISMA guidelines to identify studies that evaluated the biomechanical properties of SA and TO techniques for repair of a ruptured QT. The search phrase used was “quadriceps tendon repair biomechanics”. Evaluated properties included ultimate load to failure (N), displacement (mm), stiffness (N/mm), and mode of failure.

Results

Five studies met inclusion criteria, including a total of 72 specimens undergoing QT repair via the SA technique and 42 via the TO technique. Three of 4 studies found QTs repaired with SA to have significantly less elongation upon initial cyclic loading when compared to QTs repaired with the TO technique (P < .05). Three of 5 studies found QTs repaired with SA to have significantly less elongation upon final cyclic loading when compared to QTs repaired with the TO technique (P < .05). The pooled analysis from 4 studies reporting on initial displacement showed a statistically significant difference in favor of the SA group compared to the TO group (P = .03). The pooled analysis from studies reporting on secondary displacement and ultimate load to failure showed no significant difference between the SA and TO groups (P > .05). The most common mode of failure in both groups was suture slippage.

Conclusion

On the basis of the included cadaveric studies, QTs repaired via the SA technique have less initial displacement upon cyclic testing when compared to QTs repaired via the TO technique. However, final displacement and ultimate load to failure outcomes did not reveal differences between the two fixation strategies. Knot slippage remains a common failure method for both strategies.

Suture Anchor Repair With Fully Threaded Knotless Anchors for Quadriceps Tendon Rupture Resulted in Favorable Outcomes After 2 Years

Purpose

To investigate clinical outcomes over 2 years in cases of quadriceps tendon rupture (QTR) that were surgically treated using fully threaded knotless anchors.

Methods

A total of four knees in four male patients with QTR repaired with fully threaded knotless anchors at our hospital from November 2017 to January 2019 were enrolled. Mean patient age at surgery was 65.3 years (range: 61-70 years). Intraoperatively, stability of the sutured site was confirmed by knee flexion to 90°. Full weight walking with the orthosis in extension was commenced on the seventh postoperative day. Surgical findings, pathologies of the ruptured quadriceps tendons, and postoperative clinical outcomes were evaluated in all patients.

Results

The QTR was complete in three cases and partial in one. Average surgical duration was 58.5 (range: 49–74) minutes. Pathological evaluation revealed hyaline degeneration with granulation of the quadriceps tendon in two cases. No complications, such as infection and rerupture, occurred. Magnetic resonance imaging performed 1 year postoperatively confirmed complete healing of the repaired tendon. The mean follow-up period was 35.5 months (range: 24–46 months). None of the patients had extension lag of the knee, and mean Lysholm score and range of flexion were 95.3 (range: 85–100) and 141.3° (range: 140–145°), respectively, at the final follow-up.

Conclusions

Clinical outcomes were favorable in all cases, including two cases with pathological degenerative changes. Suture anchor repair with fully threaded knotless anchors can be considered a minimally invasive and effective method for QTR, with sufficient strength to allow early rehabilitation.

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.

High rates of return to play and work follow knee extensor tendon ruptures but low rate of return to pre-injury level of play

PURPOSE

Extensor mechanism ruptures (EMR) of the knee are rare but debilitating injuries that always require surgery to restore knee function. The purpose of this study was to systematically review the literature to ascertain the rate of return to play following patellar or quadriceps tendon ruptures.

METHODS

A systematic literature search was conducted based on PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, using the EMBASE, MEDLINE, and Cochrane Library databases. Inclusion criteria consisted of clinical studies reporting on return to play after patellar or quadriceps tendon repair. Statistical analysis was performed with the use of SPSS.

RESULTS

Our review found 48 studies including 1135 cases meeting our inclusion criteria. There were 33 studies including 757 patellar tendon (PT) repairs, and 18 studies including 378 quadriceps tendon (QT) repairs. The overall rate of return to play for PT repairs was 88.9%, with 80.8% returning to the same level of play. The overall rate of return to play for QT repairs was 89.8%, with 70.0% returning to the same level of play. Among professional athletes, the overall rate of return to play after PT repair and QT repair was 76.9% and 70.9%, respectively. Following PT repair, 95.8% were able to return to work, and following QT repair, 95.9% were able to return to work.

CONCLUSION

The overall rate of return to play was high following both PT and QT repairs. Moreover, a high percentage of those patients were able to return to their pre-operative level of sport with a low risk for re-rupture.

LEVEL OF EVIDENCE

Level IV.

V-Y turndown flap augmentation for acute quadriceps rupture after total knee arthroplasty: a prospective matched cohort study

PURPOSE

To evaluate the effectiveness of the quadriceps V-Y turndown augmentation for acute quadriceps tendon ruptures in the setting of TKA.

METHODS

Prospective cohort of 22 patients with quadriceps rupture after TKA were compared with 44 matched patients underwent TKA without quadriceps rupture. Quadriceps ruptures were treated within three weeks after injury by suture augmented with Scuderi quadriceps V-Y turndown flap. Clinical evaluation was performed by the Knee Society Scores (KSS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and range of motion. Patellar height was assessed by the Blackburne-Peel ratio.

RESULTS

The mean follow-up was 3.3 (range, 3-4) years. At the final follow-up, there were significant improvements in mean KSS scores in both groups (p = 0.001). In the quadriceps group, the mean flexion for all patients, but one with arthrodesis for periprosthetic infection, was 100.1° (range, 90-110°) and mean extensor lag was 7.1° (range, 0-20°). There were significant differences between groups in KSS scores (p = 0.001). Active flexion (p = 0.020) and extension (p = 0.001) were significantly better in the control group. However, there was no significant difference in WOMAC scores (p = 0.252) or patient satisfaction (p = 0.352). There were no quadriceps reruptures. One patient with periprosthetic infection was treated with arthrodesis.

CONCLUSION

The quadriceps V-Y turndown is an effective and safe procedure for quadriceps ruptures in the setting of TKA. Although the functional outcomes were lower than in TKA patients with no quadriceps rupture, the quality of life and satisfaction were successful in the TKA patients with quadriceps rupture.

Evidence-based Risk Stratification for Sport Medicine Procedures During the COVID-19 Pandemic

Orthopaedic practices have been markedly affected by the emergence of the COVID-19 pandemic. Despite the ban on elective procedures, it is impossible to define the medical urgency of a case solely on whether a case is on an elective surgery schedule. Orthopaedic surgical procedures should consider COVID-19-associated risks and an assimilation of all available disease dependent, disease independent, and logistical information that is tailored to each patient, institution, and region. Using an evidence-based risk stratification of clinical urgency, we provide a framework for prioritization of orthopaedic sport medicine procedures that encompasses such factors. This can be used to facilitate the risk-benefit assessment of the timing and setting of a procedure during the COVID-19 pandemic.

Relationships between Quadriceps Tendon Elasticity and Knee Flexion Angle in Young Healthy Adults

Background and objectives: Although tendon elasticity by elastography is useful for diagnosing tendon disorders and planning rehabilitation regimens of the tendon, there are few reports on the quadriceps tendon. Moreover, relationships between the quadriceps tendon elasticity and knee angle have not been investigated. The purpose of this study was to clarify the relationship between quadriceps tendon elasticity and knee flexion angle in young healthy adults using elastography, and to investigate the difference in elasticity by sex and leg dominance. Materials and Methods: A total of 40 knees in 20 young healthy adults were included in this study (age: 25.5 (23.3⁻27.5) years). At knee flexion of 30°, 60°, and 90°, quadriceps tendon elasticity was measured using ShearWave™ Elastography during the ultrasound examination. Results: There were significant differences in the elasticity between all angles (p < 0.001). Elasticity was increased more at 60° than at 30° and at 90° than at 60°. Elasticity in men was higher than that in women at 60° (p = 0.029). There were no differences (p = 0.798) in elasticity at each angle between the dominant and non-dominant legs. Conclusions: The quadriceps tendon elasticity increased according to the knee flexion angle in young healthy adults. Moreover, elasticity was affected by sex, but not by leg dominance. Clinically, in a rehabilitation regimen, attention should be paid to exercises that could increase stiffness accompanying flexion of the knee to avoid further tendon damage as risk management in the acute phase.

Better knee function after surgical repair of acute quadriceps tendon rupture in comparison to acute patellar tendon rupture

INTRODUCTION

The purpose of this study was to determine if there is a difference in knee function between patients with quadriceps tendon rupture and patellar tendon rupture after acute surgical repair. Our hypothesis was that knee function would be similar between the two groups.

METHODS

The study population included 24 patients; 13 patients suffered from quadriceps tendon rupture and 11 patients from patellar tendon rupture. All patients underwent acute surgical repair using heavy non-absorbable trans-osseous sutures; another non-absorbable suture, passed through both retinaculum and around the repaired tendon to augment the repair. Clinical evaluation was performed using the Lysholm, Kujala, and VAS scoring systems. In addition, radiographic evaluation to evaluate patellar height and patello-femoral joint arthritis using Iwano's classification was performed.

RESULTS

The average follow-up time was 70.5 months. All patients in the quadriceps tendon group had full range of knee motion while 3 patients (27%) in the patellar tendon group had reduced knee flexion. Patients in the quadriceps tendon group had a significantly higher Kujala score in comparison to the patellar tendon group (88 vs. 73 p=0.033). No significant differences were identified between the two groups according to the Lysholm scoring system. Patients in the quadriceps tendon group had significantly less pain according to VAS scale (1.2 vs. 3.5 p=0.012). Radiographic evaluation revealed that two patients from each group showed signs of grade II patello-femoral joint arthritis according to Iwano's classification.

CONCLUSION

Acute surgical repair of quadriceps tendon ruptures provides better knee function, in comparison to the surgical restoration of patellar tendon rupture.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Acute quadriceps tendon rupture repaired by suture anchors: Outcomes at 7 years' follow-up in 25 cases

INTRODUCTION

Acute quadriceps tendon rupture is rare. The gold-standard repair technique is transosseous patellar suture. Biomechanical studies have validated the use of anchors as an alternative. The present study sought to report long-term clinical and radiological results in a series of acute quadriceps tendon rupture repaired with anchors. The study hypothesis was that results are comparable to those of the gold-standard technique.

METHODS

A retrospective continuous study included 25 knees with acute quadriceps tendon rupture, operated on by a single surgeon between 2007 and 2013: 22 patients; 17 males, 5 females; mean age, 64 years (range: 52-87 years). Modified Bunnell suture was performed, using either 2 anchors (19 knees) or 3 anchors (6 knees). Anchors were positioned under 20° flexion. The factors studied were: active range of motion, muscle strength, patient satisfaction, Lysholm score, return to work, and the radiological behavior of the anchors.

RESULTS

At a mean follow-up of 7 years (range: 3-9 years), all but 1 patient had 0° active extension. Mean active flexion was 128° (range: 110-150°), and mean muscle strength was 4.9/5. Mean Lysholm score was 92. Subjective results proved satisfactory or very satisfactory in 23 cases. Working patients returned to work at a mean 4.2 months. There were no cases of anchor migration or of re-rupture. One poorly tolerated anchor was ablated at 2 years, without functional impact.

CONCLUSION

Outcomes with anchors were comparable to those of the gold-standard technique. Anchors allow immediate rehabilitation, without risk of anchor migration. The technique provided satisfactory functional recovery.

LEVEL OF EVIDENCE

IV, retrospective cohort study.

Arthroscopic suture repair of acute quadriceps tendon ruptures

Acute quadriceps tendon ruptures disrupt the continuity of the extensor mechanism and must be treated surgically. Tendon reattachment with suture anchors has recently been shown to be biomechanically superior to reattachment through transosseous tunnels. In this context, arthroscopy is an interesting alternative. It can limit postoperative wound healing and infectious complications, while ensuring functional outcomes that are equivalent to standard techniques. The goal of this technical note is to describe an original, reproducible method for arthroscopic reattachment of the quadriceps tendon with suture anchors. Four patients were operated using this technique in a pilot study. No wound healing, infectious complications or re-tears were observed. At 6 months' postoperative, the mean subjective IKDC score was 85.8/100.

Total ruptures of the extensor apparatus of the knee

OBJECTIVE

This was a retrospective case-control study on total ruptures of the extensor apparatus of the knee, aimed to compare patella fractures with tendinous ruptures.

METHODS

The sample included 190 patients and 198 total ruptures of the knee extensor apparatus. All patients were evaluated by the same examiner after a minimum one-year follow-up.

RESULTS

Tendinous ruptures occurred most frequently in men, in younger patients, and had better clinical and functional outcomes when compared with patella fractures; however, the former presented higher levels of thigh atrophy. Patella fractures occurred most frequently in women and in older patients and caused most frequently caused residual pain, muscle weakness, and limitations in daily activities. Comminuted fractures were related to high-energy trauma, lower clinical and functional outcomes, and higher levels of residual pain and osteosynthesis failure. Early removal of osteosynthesis material was related to better outcomes. Regarding the tendinous ruptures, over half of the patients presented risk conditions for tendinous degeneration; a longer delay until surgery was related to lower Kujala scores.

CONCLUSION

The surgical repair of bilateral ruptures of the knee extensor apparatus resulted in satisfactory clinical and functional outcomes, which were better for tendinous ruptures when compared with patella fractures. However, these lesions are associated with non-negligible levels of residual pain, muscle weakness, atrophy, and other complications.

Knotless Suture Anchor With Suture Tape Quadriceps Tendon Repair Is Biomechanically Superior to Transosseous and Traditional Suture Anchor-Based Repairs in a Cadaveric Model

PURPOSE

To compare the biomechanical properties of a knotless suture anchor with suture tape quadriceps tendon repair technique with transosseous and suture anchor repair techniques.

METHODS

Twenty matched pairs of cadaveric knees underwent a quadriceps tendon avulsion followed by repair via the use of transosseous tunnels with #2 high-strength sutures, 5.5-mm biocomposite fully threaded suture anchors with #2 high-strength sutures, or 4.75-mm biocomposite knotless suture anchors with suture tape. Ten knees were repaired via transosseous repair and 10 via fully threaded suture anchor repair, and their matched specimens were repaired with suture tape and knotless anchors. Biomechanical analysis included displacement during cyclic loading over 250 cycles, construct stiffness, ultimate load to failure, and failure mode analysis.

RESULTS

Compared with transosseous repairs, quadriceps tendons repaired with knotless suture tape demonstrated significantly less displacement during cyclic loading (cycles 1-20 3.6 ± 1.3 vs 6.3 ± 1.9 mm, P = .003; cycles 20-250 2.0 ± 0.4 vs 3.1 ± 0.9 mm, P = .011), improved construct stiffness (67 ± 25 vs 26 ± 12 N/mm, P = .001), and greater ultimate load to failure (616 ± 149 vs 413 ± 107 N, P = .004). Our repair technique also demonstrated improved biomechanical parameters compared with fully threaded suture anchor repair in initial displacement during cyclic loading (cycles 1-20 3.0 ± 0.8 vs 5.1 ± 0.9 mm, P < .001), construct stiffness (62 ± 20 vs 28 ± 10 N/mm, P = .001) and ultimate load to failure (579 ± 129 vs 399 ± 87 N, P = .006).

CONCLUSIONS

Repair of quadriceps tendon ruptures with this knotless suture anchor with suture tape repair technique is biomechanically superior in cyclic displacement, construct stiffness, and ultimate load to failure compared with transosseous and fully threaded suture anchor techniques in cadaveric specimens.

CLINICAL RELEVANCE

The demonstration that our repair technique is biomechanically superior to previously described techniques in a cadaveric setting suggests that consideration should be given to this technique.

Biomechanical Evaluation of Suture Anchor Versus Transosseous Tunnel Quadriceps Tendon Repair Techniques

PURPOSE

To evaluate the biomechanical fixation strength of suture anchor and transosseous tunnel repair of the quadriceps tendon in a standardized cadaveric repair model.

METHODS

Twelve "patella-only" specimens were used. Dual-energy X-ray absorptiometry measurement was performed to ensure equal bone quality amongst groups. Specimens were randomly assigned to either a suture anchor repair of quadriceps tendon group (n = 6) or a transosseous tunnel repair group (n = 6). Suture type and repair configuration were equivalent. After the respective procedures were performed, each patella was mounted into a gripping jig. Tensile load was applied at a rate of 0.1 mm/s up to 100 N after which cyclic loading was applied at a rate of 1 Hz between magnitudes of 50 to 150 N, 50 to 200 N, 50 to 250 N, and tensile load at a rate of 0.1 mm/s until failure. Outcome measures included load to failure, displacement at 1st 100 N load, and displacement after each 10th cycle of loading.

RESULTS

The measured cyclic displacement to the first 100 N, 50 to 150 N, 50 to 200 N, and 50 to 250 N was significantly less for suture anchors than transosseous tunnels. There was no statistically significant difference in ultimate load to failure between the 2 groups (P = .40). Failure mode for all suture anchors except one was through the soft tissue. Failure mode for all transosseous specimens but one was pulling the repair through the transosseous tunnel.

CONCLUSIONS

Suture anchor quadriceps tendon repairs had significantly decreased gapping during cyclic loading, but no statistically significant difference in ultimate load to failure when compared with transosseous tunnel repairs. Although suture anchor quadriceps tendon repair appears to be a biomechanically superior construct, a clinical study is needed to confirm this technique as a viable alternative to gold standard transosseous techniques.

CLINICAL RELEVANCE

Although in vivo studies are needed, these results support the suture anchor technique as a viable alternative to transosseous repair of the quadriceps tendon.

Acute traumatic patellar tendon rupture: Early and late results of surgical treatment of 38 cases

INTRODUCTION

Acute patellar tendon rupture is easy to diagnose but is still often overlooked. The aim of this study was to assess early and late results of surgical treatment of acute patellar tendon rupture. Our hypothesis was that functional outcome is satisfactory.

METHODS

A retrospective study included 38 knees in 37 patients (4 female, 33 male). Mean age was 42.6 ± 9.9 years (range, 23-81 years). Lesions comprised 15 tendon body ruptures, 20 avulsions from the tip of the patella and 3 avulsions from the anterior tibial tuberosity. Tendon repair was protected in more than 95% of cases by a reinforcement frame: hamstring (21 cases), synthetic ligament (12 cases) or metallic wire (3 cases). Results were evaluated in 2 steps: on patient files at a mean follow-up of 7.1 months (range, 3-24 months) to assess complications and early functional and radiological results; and by phone at a mean follow-up of 9.3 years (range, 19-229 months) in order to assess long-term functional outcome on Lysholm score and patient satisfaction.

RESULTS

Thirty-one knees were assessed at a mean 7.1 months. Mean knee flexion was 128.5° ± 7.5° (range, 85°-150°), extension -1° (range, -15° to 0°) and Caton-Deschamps index 0.96 (range, 0.57-1.29). Twenty-three knees were further assessed at a mean 9.3 years. Mean Lysholm score was 93.7 points (range, 61-100). Ninety-six percent of patients were satisfied or very satisfied with the result. All had returned to their previous job, and 20 had returned to sports activities, including 8 at pretrauma level.

CONCLUSION

Patellar tendon rupture has good prognosis if diagnosis and surgical treatment is early.