Patellar Tendon Research Articles

Patellar resurfacing in contemporary total knee arthroplasty: Frequency of complications in a matched cohort

IntroductionOptimum patient selection and outcomes following patellar resurfacing are ongoing debates amongst the arthroplasty community. This study compared the outcomes of patients who had a total knee arthroplasty (TKA) with patellar resurfacing to those left with their native patella. MethodsA retrospective review of 1941 TKAs performed between 2016 and 2020 was conducted. 41 TKAs without patellar resurfacing and with 2-years of minimum follow-up were identified. Of these, 38 TKAs were matched on age (exact), sex (exact), and body mass index (±10) to 38 TKAs that had patellar resurfacing. The indications for patella resurfacing were subjective based upon the surgeon preference and assessment of cartilage quality. Paired t-tests and chi-square tests were used for analysis. ResultsThere was 1 major patellofemoral complication in both the resurfaced group (patellar fracture) and the non-resurfaced group (patellar tendon tear), requiring nonoperative management and revision surgery, respectively. However, in the non-resurfaced group there were 4 cases of subjective patellofemoral pain compared to none in the resurfaced group (p = 0.37). Additionally, 3 non-resurfaced patients required manipulation under anesthesia (MUA) compared to none in the resurfaced group (p = 0.44). DiscussionThere was no difference in the frequency of major patella-specific complications between the groups. However, there was a non-statistically significant trend towards increased patellofemoral pain and MUA in the non-resurfaced group. Based on this study both methods of treatment remain viable options, but the trend towards increased pain and stiffness should continue to be closely evaluated.

Functional Outcome in Obese Patients Undergoing Image-Based Cruciate Retaining Robotic-Assisted Total Knee Arthroplasty Using the Subvastus Approach: A Short-Term Study.

Introduction Knee osteoarthritis (OA) is a prevalent degenerative joint disease that significantly affects quality of life, especially among obese and morbidly obese individuals. Total knee arthroplasty (TKA) is an effective treatment for end-stage OA, but it presents unique challenges in obese patients. The mini-subvastus approach (SA) and robotic-assisted TKA (RA-TKA) are emerging techniques that may address these challenges. This study evaluates the clinical and radiological outcomes of cruciate-retaining (CR) RA-TKA using the mini-subvastus approach in obese and morbidly obese patients. Methods This study included 114 obese patients (215 knees) with primary OA who underwent CR RA-TKA (Maxx Meril CR knee, USA) using the Cuvis Joint® robotic system. Patients had a BMI of ≥30 kg/m² (n=101) and morbid obesity with a BMI ≥40 kg/m² (n=13). Preoperative planning involved CT scans and the J-planner for optimal implant size and positioning. Surgery was performed without tourniquets, and patients were mobilized postoperatively. Clinical outcomes were assessed using visual analog scale (VAS) scores and the American Knee Society Score (AKSS) at three and six months. Results The study included 85 females and 29 males with an average age of 61.8 years. Satisfactory knee exposure was achieved in all cases using SA, with no major complications such as wound infections, deep vein thrombosis, or component misalignment. Intraoperative challenges were managed effectively, including two cases of medial collateral ligament avulsion and one partial patellar tendon avulsion. Postoperative VAS scores showed significant pain reduction from pre-op (6.54) to post-op day 3 (1.3). AKSS improved from a pre-op average of 33.9 to 70.7 at three months and 80.9 at six months. Most patients (80%) achieved exceptional range of motion (ROM) ≥120° at six months. Discussion The mini-subvastus approach in RA-TKA offers several advantages, including reduced postoperative pain, faster recovery, and improved quadriceps strength, even in obese patients. The use of robotic assistance ensures accurate component positioning and alignment, mitigating the challenges typically associated with obese patients undergoing TKA. Conclusion The study demonstrates the feasibility and effectiveness of CR RA-TKA using the mini-subvastus approach in obese and morbidly obese patients. This technique provides adequate exposure, reduces pain, and promotes early mobilization and recovery with satisfactory clinical and radiological outcomes. The findings support the potential for wider adoption of this approach in managing knee OA in obese populations, though further studies with longer follow-up are warranted.

Reliability testing of sonographic techniques in detecting lateral displacement of patellar tendon

ObjectivesPatellofemoral pain syndrome (PFPS), a common knee condition, is characterized as presence of peripatellar pain during activities especially during loading of the lower extremity. Gonzalez-Suarez et al. (2021) developed a sonographic technique that assessed patellar tendon displacement within the trochlear groove. This study aims to determine the reliability of this sonographic technique. MethodsIntra-rater and inter-rater reliability study of three sonologist on the lateral displacement of the patellar tendon using ultrasound. Patellar tendon displacement was assessed using the three novel sonographic measurement techniques: 1) region of trochlear groove where the patellar tendon midpoint is located, 2) distance between deepest portion of the trochlear groove and patellar tendon midpoint and 3) percentage of lateral displacement of the patellar tendon. The measurements were done with the patients in supine and standing. ResultsTen participants with a mean age of 27.6 ± 1.56 years were included in the study. Pilot studies were done to improve the sonographic technique. Intraclass correlation coefficients yielded good to excellent inter-rater and excellent intra-rater reliability (>0.75) in the supine and standing positions except the inter-rater reliability of the region of the trochlear groove where patellar tendon midpoint is in supine position. ConclusionThe sonographic techniques for measurement of lateral patellar tendon displacement showed good to excellent intra-rater and inter-rater reliability between sonologists of different levels of expertise using a well-defined scanning protocol.

Patellar Tendon Debridement and Reconstruction With Hamstring Tendon Autografts in the Setting of Severe Patellar Tendinopathy

Background: Patellar tendinopathy is a multifactorial condition characterized by micro-degenerative changes in the patellar tendon. This results from repeated stress to the knee extensor mechanism from explosive movement, axial malalignment, and/or abnormal patellar height. Currently, there is no standard surgical procedure for the treatment of severe patellar tendinopathy. Indications: Patellar tendon reconstructions for patellar tendinopathy may be indicated when >50% of the tendon attachment is degenerative and detached from the distal patella and non-operative treatment, like physical therapy, bracing, and injections, have not relieved symptoms. Debridement may not offer long-term viability against augmentation of the patellar tendon with autografts, with a risk of recurrent breakdown of the patellar tendon attachment with resumption of previous activities that initially lead to overload. Technique Description: An anterior incision was made from the superior pole of the patella to the tibial tubercle. Then, dissection was performed medially to harvest the gracilis and semitendinosus tendons. Open harvesters were used, and the hamstring tendons were released proximally, keeping the tibial insertions attached. A horizontal pin was drilled across the tibial tubercle and reamed with a 4.5 mm reamer. A passing stitch was fed through the tunnel. The proximal and distal margins of the patella were localized with spinal needles and a pin was drilled across its midportion, 5 mm deep to the dorsal cortical margin, and then rearmed. Degenerative tissue at the patellar tendon was excised. The gracilis tendon was passed medial to lateral through the tibial tubercle, and a Q-Fix anchor anchored the grafts medially and laterally. The semitendinosus graft was passed medial to lateral through the patella followed by the gracilis tendon lateral to medial. Appropriate reconstruction graft tension was confirmed and grafts were whipstitched together. Results: Clinical outcomes for the debridement of severe patellar tendinopathy report 77% symptomatic relief. With many unable to return to activity, patellar tendon reconstruction can be indicated. Outcomes for reconstructions for severe patellar tendinopathy are not reported. Discussion: Patellar tendon reconstruction with hamstring autografts for the treatment of severe patellar tendinopathy can provide a strong reconstruction graft to allow for the resumption of high-level activities. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Tendon structure, clinical tests, and pain during-loading in young female competitive gymnasts

ABSTRACT To examine the relationship between Achilles-tendon (AT) and patellar-tendon (PT) structure, clinical-examination and tendon pain in young gymnasts; and, to explore the associations between these factors and age, maturation, and training-load. Two hundred and seventy-four female gymnasts (aged 12.1±1.9 yrs) were assessed for anthropometric measures, pubertal-stage, and training-load. They had clinical-tests (pain-on-palpation for AT and pain-on-palpation and Royal-London Hospital-Test for PT), were asked about tendon-pain during-loading and were assessed for tendon-structure. Gymnasts with positive clinical-tests (with and without pain during-loading) presented a significantly higher prevalence of disorganized AT and PT compared to gymnasts with negative clinical-tests (with and without pain during-loading) (p<0.05). A significant pubertyXpositive clinical-test interaction was found for disorganized PT structure, whereby a disorganized structure was more prevalent among post-pubertal gymnasts with positive clinical-tests compared to pre-pubertal participants with negative clinical-tests (F(1, 263)=9.436, p=0.002). In gymnasts with positive clinical-tests, significant correlations were found between disorganized AT and PT structures and age, and training-load (p<0.05). An increased prevalence of disorganized tendon structure (regardless of pain during-loading) was seen in participants with positive clinical-tests. This disorganized tendon-structure was found to be significantly related to increased age, post-pubertal stage, and higher training hours in gymnasts with positive clinical-tests.

Association Between Longitudinal Changes in Patellar Tendon Abnormality and Land-Jump Biomechanics in Male Collegiate Basketball Players.

The relationship between self-reported symptoms and the severity of patellar tendon abnormality (PTA) as seen on magnetic resonance imaging and ultrasound is unclear, but biomechanical testing may resolve this. To (1) compare land-jump limb biomechanics between pre- and postseason timepoints, (2) assess whether seasonal changes in biomechanics are associated with seasonal changes in PTA and symptom severity, and (3) explore models that identify seasonal changes in PTA and symptoms with seasonal changes in biomechanics in collegiate basketball players. Cohort study; Level of evidence, 2. Victorian Institute of Sport Assessment Scale - Patellar Tendon (VISA-P) scores and bilateral measurements from 18 National Collegiate Athletic Association Division I and II male basketball players (n = 36 limbs) at the preseason (visit 1) and postseason (visit 2) timepoints were collected. PTA was graded with ultrasound and magnetic resonance imaging morphology measurements proximally and distally, and 3-dimensional lower extremity sagittal kinematics and kinetics were measured during a land-jump test. Multivariate and chi-square analyses assessed timepoint differences. The association of seasonal (Δ = visit 2 - visit 1) biomechanics with seasonal morphology (ΔPTA: no change/worsened) and symptoms (ΔVISA-P: improved/no change/worsened) was tested with multivariate models. Logistic regressions modeled the accuracy of seasonal biomechanics to classify seasonal PTA and symptoms. Three athletes (6 limbs) at visit 1 and 2 athletes (4 limbs) at visit 2 were symptomatic. VISA-P scores were not significantly different between preseason and postseason. Regarding PTA, multivariate analyses found differences among grouped ground-reaction force variables (P < .05); univariate analyses found that worsened PTA was associated with seasonal decreases in peak vertical jumping force and with seasonal increases in knee flexion velocity at contact and maximum knee flexion velocity (P < .05 for all). Regarding VISA-P scores, multivariate analyses found differences among grouped hip (P < .01) and ankle (P < .05) kinematic variables; univariate analyses found that worsened VISA-P was associated with seasonal increases in hip (P < .01) and knee (P < .01) flexion velocity at contact and seasonal increases in ankle range of motion (P < .05). The findings demonstrated an association between seasonal changes in dynamic lower extremity biomechanics and seasonal changes in patellar tendon imaging signals as well as self-reported symptoms.

Understanding the Interactions Between Loading, Pain Dynamics, and Imaging Characteristics for Osgood Schlatter: A Cross-Sectional Study.

Osgood Schlatter's disease (OSD) is characterized by pain at the tibial tuberosity provoked during knee-loading activities, and is common in adolescent athletes. The aim of this studywas to characterize clinical, pain and ultrasound imaging characteristics in participants with OSD compared to controls. This cross-sectional study included adolescents diagnosed with OSD and matched controls. Following baseline evaluation including ultrasound, participants completed the following aggravating activities in a randomized order: single-leg isometric knee hold, single-leg squat, single-leg vertical jump, hopping, running, cutting, lunges, and walking. Participants rated pain intensity on a numeric rating scale (0-10; no pain to worst pain imaginable) and localization during activities. We included 35 participants with OSD (48.5% females, age 13.0 [SD 1.5]) and 21 controls (47.6% females, age 13.4 [SD1.4]). Doppler signal was more prevalent in OSD participants at the tendon (77% vs. 30%) and tuberosity (29% vs. 10%). Tendon thickness was greater in OSD at distal (mean difference = 4.5 mm 95% CI 1.5-7.5) and proximal sites (mean difference = 4.2 95% CI 0.1-8.3). Aggravating activities induced higher pain in OSD. The greatest differences between OSD and control were the dynamic single-leg squat (mean difference = 4.2 (95% CI 3.22-5.1)). Pain was localized at the tibial tuberosity and patellar tendon during activities. Sex, sports participation, bilateral pain, and Doppler were associated with greater pain during aggravating activities. Single-leg activities loading the tibial tuberosity through the tendon appear to provoke OSD-related pain more than other sports specific movements. This may be useful to guide adolescents on which activities are likely to aggravate pain.

Minimally Invasive 2-Incision Patellar Tendon Autograft Anterior Cruciate Ligament Reconstruction Using Retrograde Reamer Guide to Prevent Graft-Construct Mismatch

Graft-tunnel mismatch (GTM) is a known technical challenge that can occur with anterior cruciate ligament reconstruction when using a patellar tendon autograft. Two-incision anterior cruciate ligament reconstruction is a well-established technique with excellent outcomes and can serve as an excellent tool to prevent GTM. Traditionally, 2-incision femoral tunnel drilling has been performed using an over-the-top guide through a lateral incision, but more modern retrograde reamer guides can allow this to be done percutaneously. We detail how a minimally invasive 2-incision femoral tunnel drilling technique can be used in patients with patellar tendon lengths that are longer than average to avoid GTM.

16-Year Old Severe PCL Knee Sprain Corrected with Bone Marrow Aspirate

This case report describes the successful treatment of a 16-year-old male basketball player with chronic instability and pain in his left knee following a grade 3 posterior cruciate ligament (PCL) sprain sustained during a trampoline accident. Initial conservative management and subsequent complete healing of the PCL did not alleviate the patient's symptoms of knee instability. After thorough evaluation, including physical exam, ultrasound, and MRI review, the patient opted for an unconventional treatment approach involving whole bone marrow aspiration and prolotherapy-based injections into multiple knee structures. The treatment protocol included injections into the PCL, quadriceps tendon, patellar tendon, patellofemoral ligaments, menisci, and Hoffa’s fat pad under ultrasound and X-ray guidance. This was followed by a regimen that included platelet-rich plasma (PRP) injections, high-dose vitamin C infusions, and adjunctive therapies such as red-light therapy and pulsed electromagnetic field therapy. The patient underwent six weeks of intensive physical therapy focusing on muscle strengthening and neuromuscular re-education. Within 2.5 months post-treatment, the patient demonstrated full stability of the knee without pain or swelling, allowing a return to basketball activities. Subsequent follow-ups at six months and one year revealed sustained improvement with no recurrence of symptoms, enabling unrestricted participation in competitive basketball. This case highlights the successful utilization of comprehensive regenerative medicine techniques and rehabilitation strategies in resolving chronic knee instability and facilitating return to sport in a young athlete.

Comparison of Time Needed to Meet Common Rehabilitation Milestones After Anterior Cruciate Ligament Reconstruction According to Graft Type

Background: The use of bone–patellar tendon–bone (BPTB) and hamstring tendon (HT) autografts is common in anterior cruciate ligament reconstruction (ACLR). After ACLR, patients typically progress through specific rehabilitation milestones, and graft type may play a role in patient progression. Purpose: To compare the time to meet rehabilitation milestones between BPTB and HT autografts after ACLR. Design: Cohort study; Level of evidence, 3. Methods: This was a single-institution study on patients who underwent ACLR with either BPTB or HT autograft between June 2018 and July 2021. The primary outcomes were time to meet return-to-sport criteria, including &gt;90% limb symmetry index (LSI) for isokinetic quadriceps and hamstring strength, horizontal hop, 4-crossover hop, and single-hop height. The time to satisfaction of each criterion was compared between graft groups using Wilcoxon tests and Cox proportional hazards models. Results: Included in the analysis were 410 participants who underwent ACLR with either BPTB (n = 232) or HT (n = 178). The BPTB group took longer to achieve &gt;90% LSI for knee extension than HT (11.1 ± 4.1 vs 7.63 ± 2.8 months; P &lt; .001). Similarly, the BPTB group took longer than the HT group to achieve &gt;90% LSI for horizontal hop (11.4 ± 3.5 vs 9.82 ± 2.8 months; P &lt; .001), 4-crossover hop (11.8 ± 3.6 vs 10.4 ± 2.8 months; P = .002), and single-hop height testing (11 ± 3.7 vs 8.81 ± 3.2 months; P &lt; .001). The median time to achieve &gt;90% LSI for hamstring strength was similar between groups (7.18 ± 3 vs 7.56 ± 3.1 months; P = .2). Conclusion: Patients that underwent ACLR with BPTB autograft took longer than patients with HT to meet commonly used postoperative rehabilitation milestones. Clinicians should consider these differences when guiding patients regarding graft choice, postoperative expectations, and rehabilitation.

Reduced Knee Flexion Strength 18 Years After ACL Reconstruction With Hamstring Tendon Versus Patellar Tendon

Background: Bone–patellar tendon–bone (BPTB) and double-looped semitendinosus and gracilis (hamstring) grafts are commonly used for anterior cruciate ligament (ACL) reconstruction. Short-term and midterm studies show little or no differences between the 2 grafts; however, there are only a few long-term studies to compare results between the 2 grafts. Purpose: To compare the results after using either BPTB grafts or hamstring tendon grafts 18 years after ACL reconstruction. Study Design: Randomized controlled trial; Level of evidence 2. Methods: A total of 114 patients with ACL rupture between 2001 and 2004 were randomized to reconstruction with either a BPTB graft or a hamstring tendon graft. Patients were operated on at 4 major hospitals. The 18-year follow-up evaluation included anterior knee laxity measured with a KT-1000 arthrometer, defined as the primary outcome, while clinical examination (Lachman and pivot-shift tests), isokinetic testing of muscle strength, patient-reported outcome measures, and an assessment of radiographic osteoarthritis using the Kellgren-Lawrence classification were defined as secondary outcomes. Results: A total of 96 patients (84%, 47 BPTB and 49 hamstring grafts) were available for follow-up, 71 of these for clinical examination. Seven of 96 patients were excluded for ACL revision (n = 5) or knee replacement (n = 2) surgery. In total, 25 patients (10 BPTB and 15 hamstring grafts) had undergone additional surgery other than ACL revision or total knee arthroplasty. There were no significant differences between the groups in terms of anterior laxity test with KT-1000 arthrometer (primary outcome). In secondary outcomes, no significant differences between groups were reported regarding clinical examination, patient-reported outcome scores, or radiographic osteoarthritis (Kellgren-Lawrence grade 2-4 for patellofemoral joint [18 hamstring and 14 BPTB] or tibiofemoral joint [20 hamstring and 19 BPTB]), while isokinetic testing revealed that the hamstring group had a 10.7% reduction in mean peak flexion torque compared with the BPTB group at 60 deg/s (df = 59; P = .011). At 60 deg/s the mean total flexion work in the hamstring group was reduced by 17.2% compared with the BPTB group (df = 59; P = .002). Conclusion: The flexion strength in the hamstring group was significantly reduced in the operated knee after 18 years. There were no significant differences between the groups regarding subjective outcomes, patient-reported outcomes, range of motion, clinical and instrumented knee laxity, and the development of osteoarthritis. Registration: NCT05876013 (ClinicalTrials.gov identifier).

Patellar tendon restoration techniques: a systematic review of outcomes for repair and reconstruction methods.

This systematic review aims to delineate the various methods to repair or reconstruct the patellar tendon using the available literature. MEDLINE and PubMed electronic databases were searched for English language clinical studies involving patellar tendon rupture repair or reconstruction that reported patient-reported outcome scores (PROS) between January 1st, 1953 and June 17th, 2021. Data was extracted on full text articles to collect functional outcome scores and rupture category, including acute, chronic, post-total knee arthroplasty (TKA) and post-anterior cruciate ligament reconstruction (ACLR). Twenty-three studies with a total of 738 patients were included. Of the 14 studies including acute repairs, mean postoperative Lvsholm scores ranged from 84 to 99.5. Knee Society Score (KSS) and knee range of motion (ROM) measurement were the most widely reported outcomes in the chronic setting. The average postoperative KSS scores ranged from 70 to 87.7. Of the six studies that included patellar tendon repairs/reconstructions in the setting of prior TKA, the most frequently reported outcomes were KSS scores and knee ROM measurements. The average postoperative KSS scores for the three cohorts reporting reconstruction with allograft ranged from 79 to 88 as compared to the average postoperative KSS score for reconstruction with autograft of 70. Despite this heterogeneity, we concluded: (1) in the primary setting, cerclage augmentation yields the lowest lysholm scores and should not be considered, although primary repairs with and without augmentation yield comparable postoperative lysholm scores, (2) in the chronic setting, repair with augmentation and reconstruction yielded similar results aside from in post-TKA patients where allograft reconstruction yielded superior KSS scores.

Effect of a single versus serial platelet-rich plasma injection on the healing of acute patellar tendon defect: an experimental study

BackgroundThere is no consensus on the frequency and timing of platelet-rich plasma (PRP) injection in tendon healing. We aimed to evaluate the effectiveness of single versus multiple PRP injections in the healing of patellar tendon defects in the experimental model, through histological and biomechanical investigation.MethodsForty-four male skeletally mature Dutch rabbits were randomly divided into the five study groups ( A, B,C, D,E). After creating a longitudinal acute patellar tendon defect on both knees (One-third the width of the patella tendon), the right legs of the rabbits were used as the intervention group and the left legs as the control groups. Animals in groups A, B, and C were euthanized on days 7, 14, and 28, respectively, after the first PRP injection. Animals in group D received the second PRP injection on day 10 and was euthanized on day 14. Animals in group D received the second and third PRP injections on days 10 and 20, respectively, and were euthanized on day 28. The outcomes were evaluated histologically (modification of Movin’s Grading) and biomechanically.ResultsThe inflammatory condition was exaggerated in groups D and E. Load at failure was higher in the non-injected side of groups D and E, while there was no significant difference between the right and left legs of the three groups A, B and C. In other word, groups with a single PRP injection were more resistant to the increasing load compared to the groups with multiple PRP injections.ConclusionsPRP improves tendon healing if injected early after injury, while its injection after the initial phase of injury hampers tendon healing. In addition, a single PRP injection seems to be more effective than multiple PRP injection. Therefore, in cases where PRP injection is indicated for tendon repair, such as acute tendon injury, we recommend using a single PRP injection during tendon repair surgery.

High-intensity resistance training and collagen supplementation improve patellar tendon adaptations in professional female soccer athletes.

We investigated whether 10 weeks of pre-season soccer training (including high-intensity resistance exercise) with hydrolysed collagen (COL) supplementation would confer greater changes in patellar tendon (PT) mechanical and material properties compared with placebo (PLA) in professional female soccer athletes. Eleven athletes from the first team squad of a Football Association Women's Championship soccer club volunteered to participate in this study (age, 25.7±4.2 years; height, 1.68±0.04m; mass, 64.0±4.6kg). Participants were pair-matched for baseline knee extensor maximum isometric voluntary contraction torque, age, height and mass and were randomly assigned to the COL group (n=6) or PLA group (n=5). Participants were given 30g COL or energy-matched (36.5g maltodextrin and 8.4g fructose) PLA, plus 500mg vitamin C before each training session, which consisted of high-intensity lower-limb resistance exercise, plyometric or pitch-based exercise 3 days/week for 10weeks during the pre-season period. We assessed knee extensor maximum isometric voluntary contraction torque and PT properties using isokinetic dynamometry and ultrasonography before and after the intervention. The PT stiffness [COL, +15.4%±3.1% (d=0.81) vs. PLA, +4.6%±3.0% (d=0.32), P=0.002] and Young's modulus [COL, +14.2%±4.0% (d=0.65) vs. PLA, +3.4%±2.8% (d=0.15), P=0.004] increased more in COL than in PLA. There was a main effect of training on PT cross-sectional area (P=0.027), but no interaction effect (P=0.934). To conclude, 10 weeks of pre-season soccer training (incorporating high-intensity resistance exercise) with 30g COL increased PT stiffness and Young's modulus more than training alone in professional female soccer athletes. This has positive implications for improving athletic performance and mitigating injury risk.

Associations of passive muscle stiffness and muscle echo-intensity with muscle strength

Objective: Muscle tissue parameters including composition and stiffness of muscle can have an important effect on muscle strength. In this study, we aimed to investigate the relationships between muscle echo-intensity (EI), tendon stiffness and muscle strength in young men and women. Methods: Ultrasound B-mode images of the Rectus Femoris (RF), Vastus Medialis (VM) and Patellar Tendon (PT) were acquired in fifty-two healthy subjects (mean age; 27.43±5.3 years). RF, VM and PT stiffness were characterized by shear-wave elastography measurements. Quantitative evaluations were performed, including measurement of muscle and tendon thickness and muscle EI. Isometric knee extension muscle strength was measured using hand-held dynamometer. Results: RF stiffness had a good correlation with muscle strength (r=-0.46, p&lt;0.05) and had a fair correlation with EIRF(r=-0.37,p&lt;0.05), VM stiffness had a good correlation with muscle strength (r=0.42, p&lt;0.05) and had a fair correlation with EIVM (r=-0.43,p&lt;0.05) in women. RF stiffness had a good correlation with muscle strength (r=-0.54, p&lt;0.05), had a good correlation with EIRF(r=-0.41,p&lt;0.05) in men.VM stiffness had a good correlation with muscle strength(r=-0.50; p&lt;0.05), and had a good correlation with EIVM(r=-0.60,p&lt;0.05) in men. EIRF and EIVM had a good relation with muscle strength in men and women (For EIRF; r=-0.46; r=-0.54; for EIVM; r=-0.42; r=-0.50 p&lt;0.05, respectively) Conclusions: This study demonstrates that there is a relationship between isometric muscle strength and passive muscle stiffness, muscle EI. Additionally, muscle EI affects muscle stiffness in healthy men and women. Our results should be considered in elite athletes for whom the strengthening program is important.

Long-term results after medial patellotibial ligament reconstruction for the treatment of patellofemoral instability.

To evaluate long-term clinical outcomes and redislocation rate after medial patellotibial ligament reconstruction. A total of 26 knees with mean age 26.3 ± 10.6 years (25 patients, 7 males and 18 females) treated for patellar instability (at least two objective dislocations) with medialization of the patellar tendon medial third were evaluated with an intermediate clinical follow-up (FU) at a mean of 6.5 ± 2.1 years and with a final telephone interview follow-up at mean of 15.6 ± 2.5 years (11.4-20.1). Western Ontario and MacMaster Universities Osteoarthritis Index (WOMAC), Kujala, Visual Analog Scale (VAS) for pain and Tegner activity scores were used. Information about further redislocation and knee surgery was also collected. All the clinical scores had a significant improvement compared to preoperative status (WOMAC pre-op 55.9 ± 27.2 vs. WOMAC final FU 80.8 ± 22.2; KUJALA pre-op 41.0 ± 24.0 vs. KUJALA final FU 77.2 ± 24.1; VAS pre-op 6.0 ± 3.1 vs. VAS final FU 3.44 ± 2.35; TEGNER pre-op 2.1 ± 2.0 vs. TEGNER final FU 3.6 ± 1.8; p < 0.001), and the outcomes remained stable at the final follow-up compared to the intermediate follow-up (p > 0.05). A total of 4 knees had at least one redislocation at the final follow-up, while 3 knees underwent total knee replacement surgery. The redislocation-survival rate at 5 years is 92%, meanwhile is 84% at 10 and 15 years. MPTL reconstruction produced good clinical results and a survival rate of 84% at a mean of 16 years follow-up and could be considered as associated procedure in case of patellofemoral instability. Level IV.

Reconstruction of the patellar tendon with autologous or allogeneic semitendinosus tendon transplant for chronic rupture

Reconstruction of apatellar tendon defect in the event of achronic rupture. Chronic rupture of the patellar tendon due to delayed diagnosis or failure of primary refixation with adehiscence that does not allow for anatomical refixation without patellar tendon shortening. Infection. Approximately 15 cm long incision from the tibial tuberosity to the patella. Depicting the rupture. Debridement of the tendon and insertion. Suture in the quadriceps tendon and distalization of the patella. If sufficient distalization of the patella is not possible, optionally perform aVY-plasty of the quadriceps tendon. Measuring the dehiscence. Securing the height of the patella by applying apatellotibial cerclage (strong suture cord). Extension of an existing tendon stump using aZ-plasty. Creation of 2bone tunnels (diameter approx. 5 mm) in the patella and the tibial tuberosity. Insertion of an autologous or allogeneic semitendinosus tendon transplant and securing it by knotting the retaining threads in front of the tibial tuberosity. Six weeks of partial weight-bearing with 10 kg of body weight in astraight, removable splint. Range of movement: weeks 1-4 E/F 0-0-60°, weeks 5-6 E/F 0-0-90°. Seven patients who underwent this surgery as described above had aminimum follow-up of 2years. Secondary lengthening of the quadriceps tendon had to be performed twice due to excessive retraction. All patients were able to perform active extension postoperatively. The Lysholm score rose from 49.3 to 83.2 points. No further rupture was detectable in the final ultrasound examination.

Morphology and morphometry of the patella in a select Black South African sample

BackgroundFor many years, sex determination has been achieved through analysis of skeletal remains in forensic medicine. The patella can be utilized for sex determination in the absence (or damage) of the cranium, upper and lower limbs, and pelvic bones. Additionally, understanding the patella's morphology and morphometry is essential for diagnosing and treating injuries and disorders of the knee joint, as well as knee arthroplasty and patella ligament grafting (Medeiros et al., 2001). This study reviewed the morphology and morphometry of the patella in a Black African population of KwaZulu-Natal and determined if a correlation between the parameters of the patellae and sex exists. Materials and methods154 dry patellae belonging to a South African black population group were utilized to review their morphology and morphometry. The classifications of Wiberg (1941) and Borges et al. (2016) were adapted for the morphology. The seven morphometric measurements were adapted from Dayal and Bidmos (2005) and Borges et al. (2016). A p-value less than 0.05 was considered statistically significant. ResultsAccording to the Wiberg classification: Type 1 patellae were least prevalent (1.9 %), while Type 2 were most common with an incidence of 59.7 %. No statistical difference was recorded with sex (p-value = 0.517). According to Borges et al. (2016) classification: Type 1 (triangular-shaped) patellae were most prevalent in males and females (72.7 %) and Type 3 (irregular shape) patellae were least common in this study. A statistically significant difference between Borges et al. (2016) classification scheme (shape of the patella) and sexes was recorded (p-value = 0.003). A statistically significant relationship between morphometric parameters of the patella and sex was also recorded (p-value <0.001). Patella measurements were greater in males than in females. ConclusionIn this study, the patella displayed sexually dimorphic morphological and morphometric characteristics, which indicated that the patella may be used for sex determination in forensic cases with the KwaZulu-Natal population of South Africa, in addition to clinical applications such as knee arthroplasty, patellar ligament grafting, prosthesis synthesis, and patellar implants.

Substantiating the Use of Tendotonometry for the Assessment of Achilles and Patellar Tendon Stiffness: A Systematic Review.

To systematically describe the next relevant aspects of tendotonometry in (1) its validity and reliability, (2) differences between populations, (3) the effect of interventions, and (4) differences between healthy and symptomatic Achilles tendon (AT) and patellar tendon (PT). Three online databases (PubMed, Embase, and EBSCOhost) were systematically searched on the 10th of October 2023. All scientific literature concerning the use of tendotonometry in assessing tendon stiffness was collected. Articles were eligible if tendotonometry with a myotonometer digital palpation device was used to assess PT or AT stiffness in adults. Thirty-four studies were included, which were categorized into studies regarding the (1a) reliability and (1b) validity of tendotonometry, (2) differences in stiffness between populations, (3) changes in stiffness due to interventions, (4) stiffness of healthy compared with injured tendons, and (5) other observational studies. The inter-rater and intrarater reliability of tendotonometry appeared to be good in assessing AT and PT stiffness, with only moderate evidence for the AT and inconclusive evidence for the PT. There is high certainty evidence that tendotonometry can detect differences in AT and PT stiffness after training interventions. Inconsistent results were found for the adequacy of tendotonometry to detect differences in AT and PT stiffness between populations. This review shows a potential role for tendotonometry in measuring tendon stiffness. However, more research is needed for validating the use of tendotonometry in AT and PT and its exact clinical interpretation.

Comparison of a handheld ultrasound device with cart-based ultrasound for the assessment of gout lesions in people with established gout

ObjectivesUse of handheld portable ultrasound is increasing and would improve access for people with rheumatic disease when conventional, cart-based ultrasound is unavailable. This study compared handheld and cart-based ultrasound for the assessment of gout lesions in people with gout. MethodsThe lower limbs of 21 participants with gout were independently scanned at six sites (1st and 2nd metatarsophalangeal joints, knee, patellar ligament, Achilles tendon, and peroneal tendons) using cart-based (LOGIQ P9) and handheld (Vscan Air™) ultrasound by two rheumatologists. One rheumatologist was randomized to scan the right or left leg first with the cart-based or handheld ultrasound. The other rheumatologist scanned the legs in the opposite order with the imaging devices reversed. Images were saved and blinded images scored for double contour, tophus, erosion and aggregates using OMERACT definitions by two rheumatologists experienced in gout ultrasound. ResultsOn handheld ultrasound, 90% of participants had at least one site with double contour, tophus and erosions, and 100% had at least one site with aggregates. There were similar findings using cart-based ultrasound. However, site-level inter-device analysis showed only fair-good agreement: kappa (percentage agreement) for double contour 0.22 (67%), tophus 0.46 (77%), erosion 0.63 (83%) and aggregates 0.37 (75%). There were more aggregates detected by cart-based ultrasound in joints and more tophi detected by handheld ultrasound in ligaments and tendons. ConclusionsHandheld ultrasound can detect gout lesions in people with established gout. However, concordance between cart-based and handheld ultrasound in detection of some gout lesions is low, particularly double contour and aggregates.