Recurrent position and innervation pattern of recurrent peroneal nerve: A cadaveric study

BACKGROUND

The recurrent peroneal nerve (RPN) branches from the common peroneal nerve or the deep peroneal nerve and it innervates to the lower patellar region. It has recently been reported that damage to the RPN causes pain in the lower patellar region; therefore, this study examined the recurrent position and the innervation pattern of the RPN.

METHODS

Cases of knee deformity or atrophy were excluded, and 50 legs (25 males and 25 females) of 34 cadavers (15 males and 19 females) were examined to assess the recurrent position and the innervation pattern of the RPN.

RESULTS

The recurrent position of the RPN was 27.9 ± 3.6 mm from the tip of the fibula. The RPN innervated to the patellar tendon in five of the 50 legs (10%), to the infrapatellar fat pad in 13 legs (26%), and to both the patellar tendon and the infrapatellar fat pad in 20 legs (40%), and to neither the patellar tendon nor the infrapatellar fat pad in 12 legs (24%). No significant sex differences were observed in the recurrent position and the innervation pattern of the RPN.

CONCLUSIONS

In all cases, the recurrent position of the RPN was almost fixed from the tip of the fibula. The RPN frequently innervated to the patellar tendon or the infrapatellar fat pad (76%) in both males and females. These findings would be useful in knee surgery to preserve the RPN or for the diagnosis of pain in the lower patellar region.

Patellar tendon reconstruction with hamstring autograft for the treatment of chronic irreparable patellar tendon injuries

BACKGROUND

Patellar tendon injuries not amenable to primary repair present a challenging problem for surgeons and patients alike. No standard surgical technique exists for these injuries and few studies report outcomes after surgical treatment.

METHODS

A retrospective analysis was conducted for patients undergoing surgical treatment for irreparable patellar tendon tears. Patients were treated with an indirect tendon reconstruction technique using high-strength suture to set initial patellar height and hamstring autograft for biologic augmentation. Patients who underwent this procedure between 2012 and 2018 and met minimum two-year follow-up with completion of all outcome measurements including KOOS, PROMIS, VAS pain and satisfaction scores were included.

RESULTS

Eleven patients met inclusion criteria. Ten of eleven patients (91%) had intact repairs and final patient outcomes were collected at a mean of 54.9 ± 23.1 months after surgery. Only one patient experienced extensor lag at final follow-up (p < 0.001). The preoperative Caton-Dechamps ratio was 1.77 ± 0.58, which decreased to 0.98 ± 0.25 after surgery (p < 0.001). The mean postoperative KOOS ADL score was 61.5. The mean postoperative PROMIS Global Mental and Physical Health scores were 46.9 ± 8.7 and 42.0 ± 9.8. Post-operative mean VAS satisfaction score was 5.6 ± 3.4.

CONCLUSIONS

Patellar tendon reconstruction with autologous hamstring tendon graft and suture augmentation allows for acceptable outcomes in the setting of patellar tendon disruption with segmental defects when direct repair is not possible.

Surgical Induction of Posttraumatic Osteoarthritis in the Mouse

Given the prevalence and the scope of the personal and societal burden of osteoarthritis (OA), investigators continue to be deeply interested in understanding the pathogenic basis of disease and developing novel disease modifying OA therapies. Because joint trauma/injury is considered a leading predisposing factor in the development of OA, and since posttraumatic OA is one of the most common forms of OA in general, large animal and rodent models of knee injury that accurately recapitulate the OA disease process have become increasingly widespread over the past decade. To enable study in the context of defined genetic backgrounds, investigative teams have developed standardized protocols for injuring the mouse knee that aim to induce a reproducible degenerative process both in terms of severity and temporal pacing of disease progression. The destabilization of the medial meniscus (DMM) is one of the most commonly employed surgical procedure in rodents that reproducibly models posttraumatic OA and allows for the study of disease progression from initiation to end-stage disease. The description provided here sets the stage for both inexperienced and established investigators to employ the DMM procedure, or other similar surgical destabilization methods, to initiate the development of posttraumatic OA in the mouse. Successful application of this method provides a preclinical platform to study the mechanisms driving the pathogenesis of posttraumatic OA and for testing therapeutic strategies to treat it.

Sclerotherapy and prolotherapy for chronic patellar tendinopathies - a promising therapy with limited available evidence, a systematic review

Chronic Patellar tendinopathy (CPT) is a frequent overuse disorder in athletes and active people. Sclerotherapy (ST) and prolotherapy (PT) are, among a wide range of conservative treatment options, two promising therapies and have shown positive results in other tendinopathies. Since the treatments' efficacy and safety are still not defined, this review sought to answer questions on recommendations for use in clinical utility, safety, and how to perform the injection in the most effective way. An electronic database search was conducted following the PRISMA guidelines. Inclusion criteria were set up according to the PICOS-scheme. Included were athletes and non-athletes of all ages with diagnosed painful CPT. Studies including patients suffering from patellar tendinopathy which can be originated to any systemic condition affecting the musculoskeletal system (e.g. disorders associated with rheumatism) and animal studies were excluded. Methodological quality (modified Coleman Methodology Score) and risk of bias (Cochrane Risk of Bias Assessment Tool 2.0) were assessed by two independent reviewers, with disagreements resolved with a third reviewer. The search yielded a total of 416 entries. After screening titles, abstracts, and full texts, ten articles were found for qualitative analysis. The mean Coleman Score was 64.57. Three randomized-controlled trials showed positive results with an increase in VISA-P score or a decrease in VAS or NPPS, respectively. The non-randomized studies confirmed the positive results as well. Among all ten studies no serious adverse events were reported. Based on this limited set of studies, there seems to be some evidence that ST and PT may be effective treatment options to treat pain and to improve function in patients with CPT. To strengthen this recommendation, more research is needed with larger volume studies and randomized controlled studies with long term follow up. LEVEL OF EVIDENCE: IV.

The "Empty Merchant Sign" in acute patellar tendon ruptures

INTRODUCTION

We introduce a new sign on a Merchant view present in acute patellar tendon ruptures (APTR). We aim to determine the accuracy, sensitivity, and specificity of this new radiographic sign and measure the effect of a tutorial on these measures between trainees and non-trainees.

METHODS

Lateral and Merchant radiographs (22 images) of knees with four conditions (patellar instability, APTR, quadriceps tendon rupture, and controls) were randomly shown to 50 trainees and non-trainees who were asked to make a diagnosis based on radiographs. A brief tutorial was administered describing the "Empty Merchant Sign" and the same 22 images were randomly shown after the tutorial. Accuracy, sensitivity, specificity, and positive predictive value were calculated between the two image types and the effect of tutorial on these measures was assessed.

RESULTS

After the tutorial: 1. the "Empty Merchant Sign" had a higher specificity (100%) and positive predictive value (99%) compared to the lateral radiograph (81% and 64% respectively, P < 0.001), 2. There was significant improvement (from 56% to 95.3%; P < 0.001) in the accuracy of the Merchant view, making it as accurate as the lateral view (95.3% vs. 90.7%, respectively; P = 0.113). There was no difference in the accuracy of the Merchant view between trainees (97.2%) and non-trainees (90.5%) (P = 0.079).

CONCLUSION

The "Empty Merchant Sign" is a highly sensitive and specific diagnostic sign in cases of APTR. With very little training, physicians can identify this sign to diagnose APTRs on a Merchant view.

Association between increased signal intensity at the proximal patellar tendon and patellofemoral geometry in community-based asymptomatic middle-aged adults: a cross-sectional study

BACKGROUND

Histological and epidemiological data suggest that increased signal intensity at the proximal patellar tendon on magnetic resonance imaging is a response to tendon loading. As patellofemoral geometry is a mediator of loading, we examined the association between patellofemoral geometry and the prevalence of increased signal intensity at the patellar tendon in community-based middle-aged adults.

METHODS

Two hundred-one adults aged 25-60 years in a study of obesity and musculoskeletal health had the patellar tendon assessed from magnetic resonance imaging. Increased signal intensity at the proximal patellar tendon was defined as hyper-intense regions of characteristic pattern, size and distribution on both T1- and T2-weighted sequences. Indices of patellofemoral geometry, including Insall-Salvati ratio, patellofemoral congruence angle, sulcus angle, and lateral condyle-patella angle, were measured from magnetic resonance imaging using validated methods. Binary logistic regression was used to examine the association between patellofemoral geometrical indices and the prevalence of increased signal intensity at the patellar tendon.

RESULTS

The prevalence of increased signal intensity at the patellar tendon was 37.3%. A greater Insall-Salvati ratio (odds ratio 0.80, 95% confidence interval 0.66-0.97 per 0.1 change in the ratio, p = 0.02), indicative of a higher-riding patella, and a larger patellofemoral congruence angle (odds ratio 0.91, 95% confidence interval 0.85-0.98 per 5 degree change in the angle, p = 0.01), indicating a more laterally placed patella, were associated with reduced odds of increased signal intensity at the patellar tendon. Sulcus angle and lateral condyle-patella angle were not significantly associated with the odds of increased signal intensity at the patellar tendon.

CONCLUSIONS

In community-based asymptomatic middle-aged adults, increased signal intensity at the patellar tendon was common and associated with Insall-Salvati ratio and patellofemoral congruence angle, suggesting a biomechanical mechanism. Such work is likely to inform tissue engineering and cell regeneration approaches to improving outcomes in those with tendon pathology.

Ultrasonographic evaluation of the patellar tendon length and elasticity after open-wedge high tibial osteotomy: A comparison with radiological and clinical parameters

BACKGROUND

The aim of this study was to evaluate the length and elasticity of the patellar tendon after open-wedge high tibial osteotomy (OWHTO).

METHODS

This case-controlled, analytical study included patients who underwent unilateral OWHTO operation and a control group. The length, thickness, strain elastography, and strain ratio of the patellar tendon were measured. The outcome measures were the Insall-Salvati Index (ISI), Blackburne-Peel Index (BPI), Caton Index (CI), the International Knee Documentation Committee Score (IKDC), Oxford Knee Score (OKS) and Knee Injury and Osteoarthritis Outcome Score (KOOS), Ahlbäck classification, and mechanical axis. Elasticity of the patellar tendon obtained by strain elastography were graded as follows; hardest or hard tissue, intermediate tissue, and soft tissue.

RESULTS

The patellar tendon length was significantly shorter and patellar tendon thickness was significantly greater on the operated side compared with the values of the non-operated side and the control group (P<0.001 for all). Intermediate tissue was the most common elasticity grade (77%) for strain elastography on the operated side. Hardest tissue was the most common elasticity grade on the non-operated side of the patients (49.1%) and of the control group (70.0%). Patellar tendon length was correlated positively with IKDC, OKS, and KOOS values and patellar tendon thickness and strain ratio were correlated negatively with IKDC, OKS, and KOOS values.

CONCLUSION

The patellar tendon seems to be shortened and thickened, with reduced stiffness after OWHTO. The ultrasound parameters are also associated with functional outcomes.

The effects of growth on structural properties of the Achilles and Patellar tendons: A cross-sectional study

The purpose of this study was to investigate the structural properties (length and cross-sectional area) of both the Patellar and Achilles tendons at around adolescent growth spurt. One hundred-twenty children and adolescents participated in this study. Based on estimated age at peak height velocity, the participants were separated into three groups (before takeoff of adolescent growth spurt group, from takeoff of adolescent growth spurt until peak height velocity group and after peak height velocity group). An ultrasonography technique was used to determine structural properties of the Patellar and Achilles tendons. Significant group difference was observed in tendon length for the Patellar and Achilles tendons among groups. However, there were no significant differences in the ratio of the Patellar tendon to upper leg length and the ratio of the Achilles tendon to lower leg length among groups. The cross-sectional area of all regions for the Patellar and Achilles tendons in adolescents with after takeoff adolescent growth spurt group was greater than those of before takeoff adolescent growth spurt group. These results indicate that the cross-sectional area of both the Patellar and Achilles tendons increase with takeoff of adolescent growth spurt and tendons lengthen without the changes in the ratio of tendon length to bone length. In addition, the increases in the cross-sectional area of both the Patellar and Achilles tendons occur in whole regions but not specific regions.

Does Viewing the ACL Femoral Footprint End on Using a High Medial Portal Produce Better Tunnel Placement as Compared to Viewing it from a Lateral Portal while Drilling: A 3D CT-based Pilot Study

BACKGROUND

Anatomical placement of an ACL graft is critical to the clinical outcome of an ACL reconstruction. The purpose of the study was to compare the conventional technique of drilling a femoral tunnel from a medial portal while viewing it from a lateral portal versus viewing it from a high anteromedial portal and drilling it from a low medial portal. We hypothesized that the high anteromedial portal possibly provides an end-on view of the tunnel and would lead to a more favourable tunnel position.

MATERIALS AND METHODS

Sixty patients underwent arthroscopic single-bundle ACL reconstruction with a soft tissue graft. All patients had the same surgeon and same surgical technique (except viewing portal). Each patient underwent a 3D-CT 1-week post-op. We classified the patients into two groups (technique A and B) of 30 each. Postoperative tunnel position in each patient was visualized on CT scan with 3D reconstruction by the quadrant method described by Bernard et al. The distance of the centre of the femoral tunnel from the superior and posterior border of the Bernard frame was obtained in each patient of the two groups and mean value in each group was obtained and compared by Student 't' test at 5% level of significance. The position of the femoral tunnels was also studied in reference to the lateral intercondylar ridge and classified into type I (well placed), type II (moderately malpositioned) and type III (grossly malpositioned).

RESULTS

The mean distances in technique A from the posterior and superior border of the lateral femoral condyle was 35.8 ± 8.2 and 35.2 ± 6.7, and in technique B was 38.1 ± 8.6 and 35.8 ± 9.4. The two groups did not differ significantly (P > 0.05) in femoral tunnel position as visualized on 3D-CT scan postoperatively. 53.3% patients had well-placed tunnels (type I) overall with 56.67% of technique A and 50% of technique B in this group. None of the tunnels were grossly malpositioned.

CONCLUSIONS

The absence of any statistically significant difference between the groups suggests that a high anterolateral portal close to the patellar tendon gives an almost complete view of the lateral aspect of the notch, if not end on. Both techniques produced a majority of well placed (type I) tunnels.

Every layer of quadriceps tendon's central and medial portion offers similar tensile properties than Hamstrings or Ilio-Tibial Band Grafts

PURPOSE

The aim of our cadaveric study was to compare the mechanical properties of different parts of the quadriceps' tendon in a load to failure analysis as compared to three other, and most common types of grafts that are used to perform ligament's reconstruction.

METHODS

Ten fresh-frozen cadavers (5 women, 5 men) were selected from our anatomical department. Mean age at death was 64 years (48-87 years). Tendons were harvested to prepare (1) different quadriceps tendon's specimens: lateral portion (QTlat), medial portion superficial layer (QTMsup) and deep layer (QTMdeep) and central portion superficial (QTCsup) and deep layers (QTCdeep) (2) Patellar Tendon (PT), (3) Gracilis+Semi-Tendinosus specimens (GST). Specimens were stored at - 40 °C in a freezing solution. Specimens were securely attached to a dedicated loading platform, measurements were done using a validated software. Load to failure testing was then carried out. Young's Elastic moduli, ultimate Stress (MPa) and Deformation (%) were analysed.

RESULTS

The elastic moduli of the PT was significantly higher than all other grafts, all medial and central QT layers (superficial and deep) were significantly higher than its lateral part (QTlat). In terms of Ultimate Stress, all grafts were significantly greater than QTlat, PT and GST were significantly superior to QT central portions and to ITB but there did not differ with the medial portion of QT. ITB ultimate stress values were significantly higher than QTlat. The ultimate deformations of all grafts were similar.

CONCLUSIONS

This study provides reference values in in order to characterize different parts of the QT that presents anatomically and Mechanically with complex characteristics. Every Layer of Quadriceps Tendon's Central and Medial Portion Offered Similar Mechanical Properties than Two Strand Hamstrings or Ilio-Tibial Band.

Platelet-rich plasma (PRP) accelerates murine patellar tendon healing through enhancement of angiogenesis and collagen synthesis

PURPOSE

Although platelet-rich plasma (PRP) therapy has become an increasingly popular treatment for sports-related injuries, the molecular mechanisms of PRP on tissue healing process remain poorly understood. The aim of the present study was to develop an experimental method quantifying the efficacy of PRP with murine patellar tendon injury model, leading to future elucidation of the mechanisms of PRP on healing processes.

METHODS

Full-thickness defects were created in the central third of the murine patellar tendon. The prepared allogenic PRP gel was applied on the defect of the patellar tendon (PRP group), while the remaining mice served as the untreated control group. Mice were sacrificed at 2, 4, 6, 8, and 10 weeks after the operation, with histological sections obtained in each time point (n = 4 / time point / group). Semi-quantitative histological evaluation was performed in accordance with the Bonar score. The variables included in this scoring system were cell morphology, ground substance, collagen arrangement, and vascularity, with higher grades indicating worse tendon structures. In addition, the ratio of the collagen fibers to the entire tendon tissue (FT ratio) was measured using KS400 software as a quantitative histological evaluation.

RESULTS

The total Bonar score in the PRP group was significantly lower than in control group. With regard to the variables in the Bonar score, the vascularity score was significantly higher in the PRP group at 2 and 4 weeks, while the collagen arrangement score was significantly lower in the PRP group at 8 weeks. Based on a quantitative evaluation, the recovery speed of the patellar tendon determined by FT ratio was significantly faster in the PRP group than in the control group at 6 and 8 weeks.

CONCLUSIONS

We have developed an experimental method for histological and quantitative evaluation of the effects of PRP on tissue healing using murine patellar tendon injury model. The results of this study suggest that the local application of PRP could enhance the tissue-healing process both directly through action on localized cells and indirectly through the recruitment of reparative cells through the blood flow. Further investigations will be needed to confirm the mechanisms of PRP in tissue-healing processes with the development of this experimental model.

Quadriceps tendon autograft for anterior cruciate ligament reconstruction is associated with high revision rates: results from the Danish Knee Ligament Registry

PURPOSE

The quadriceps tendon (QT) has recently gained interest as an anterior cruciate ligament reconstruction (ACLR) autograft. There is a paucity of data from large cohort studies on failures and revision rates after ACLR using the QT graft. The purpose of the present study is to use the Danish Knee Ligament Reconstruction Registry (DKRR) to compare revision rates, objective knee stability and subjective clinical outcomes in patients who have undergone ACLR with QT, hamstring tendon (HT), and patellar tendon (PT) as a graft for ACLR. It was hypothesized that QT autografts would result in similar objective knee stability and revision rates as HT and PT autografts.

METHODS

Data on primary ACLRs in the DKRR from 2005 through 2017 were analyzed. Knee injury and Osteoarthritis Outcome Scores (KOOS), Tegner activity scale scores, sagittal knee laxity, pivot-shift tests at 1-year follow-up and revision rates at 2-year follow-up were compared for the three autograft cohorts.

RESULTS

A total of 531 QT, 14,213 HT and 1835 PT ACLR were registered in the DKLR between 2005 and 2017. QT autograft was associated with statistically significant increased laxity (1.8 mm) compared to HT autograft (1.5 mm) (p < 0.001) and more positive pivot shift. There was a significant higher revision rate for QT (4.7%), compared to PT (1.5%) and HT (2.3%) autografts at 2-year follow-up (p < 0.002).

CONCLUSION

Quadriceps tendon autografts for ACLR was associated with higher revision rates than HT and PT grafts. QT graft was also associated with small increased objective knee laxity and more positive pivot shift than HT and PT grafts.

LEVEL OF EVIDENCE

III.

Tendon morphological changes after a prolonged ski race can be detected by ultrasound echo intensity

BACKGROUND

Ultrasound imaging techniques have been used to assess the characteristics of skeletal muscles and tendons. Such techniques (gray scale analysis) allow qualitative evaluation and have been used recently to assess the internal structure of muscles and tendons by computer-aided gray scale analysis. We hypothesized that changes in the internal structure of the Achilles and patellar tendons after a ski mountaineering race competition could be detected with ultrasound.

METHODS

Twenty athletes were recruited during the 19th Millet Tour du Rutor extreme, a three-day ski mountaineering competition. Ultrasound measurements of the Achilles and patellar tendons were carried out before the first race and immediately after each of the three competition days. Tendon thickness, cross-sectional area (CSA), and ultrasound gray scale analysis were calculated.

RESULTS

Significant differences (p < 0.05) were observed between the pre- and post-race measurements for the Achilles tendon thickness and CSA, while no significant differences were noted for the patellar tendon thickness and CSA. However, gray scale analysis of both the Achilles and patellar tendons showed significantly higher post-race values, than the pre-race values (p < 0.05).

CONCLUSIONS

Achilles and patellar tendons of healthy athletes are highly responsive to an acute increase in mechanical load. Those changes can be detected from classical (thickness and CSA) and innovative (gray scale) ultrasound-based parameters.

TRIAL REGISTRATION

This study was approved by the Azienda USL Valle d'Aosta Ethics Committee (protocol no. 23/03/2018.0026243.I).

A simultaneous bilateral quadriceps and patellar tendons rupture in patients with chronic kidney disease undergoing long-term hemodialysis: a case report

BACKGROUND

The incidence of rupture of the quadriceps or patellar tendon s is low, especially that of bilateral quadriceps tendon rupture, and it is generally considered a complication secondary to chronic systemic disorders. We report two rare cases of simultaneous bilateral tendon rupture affecting the extensor function of the knee in patients with chronic kidney disease who have been treated with long-term haemodialysis.

CASE PRESENTATION

Two young males with a history of chronic kidney disease who were being treated with long-term haemodialysis presented to our hospital with clinical signs of disruption of the extensor mechanism of the knee. One patient was diagnosed with bilateral quadriceps tendon rupture, and the other patient had bilateral patellar tendon rupture. They underwent surgical repair of the tendons, and their knees were actively mobilized during physiotherapy.

CONCLUSION

Bilateral quadriceps or patellar tendons rupture is a rare occurrence in patients with chronic kidney disease who are being treated with long-term haemodialysis. Timely surgical treatment and scientific physiotherapy can lead to good recovery of knee joint function.

Ligament augmentation reconstruction system artificial ligaments in patellar tendon reconstruction - a chronic patellar tendon rupture after multiple operations: A case report

BACKGROUND

Patellar tendon rupture is a rare disease, and reports regarding patellar tendon reconstruction with ligament augmentation reconstruction system (LARS) ligaments are limited, with only three reports available in the literature. LARS ligaments are made of polyethylene terephthalate and have been certified as a more favorable option than other tendon transplants. To our knowledge, this is the first report of patellar tendon reconstruction with LARS for suture fixation due to poor quality of the tendon after multiple operations to enable early mobilization and quick rehabilitation.

CASE SUMMARY

A 65-year-old woman had limited ability in extending her leg and an inability to perform a straight leg raise after multiple operations due to patella fracture. The patient underwent patellar tendon reconstruction with LARS artificial ligaments. After 12 mo of follow-up, the patient was able to perform a straight leg raise, and the incision healed well without complications. The Lysholm score was 95 and the range of motion of the knee was 0-130°.

CONCLUSION

This study revealed that patellar tendon reconstruction with LARS artificial ligaments is possible in a patient with a patellar tendon rupture who required rapid postoperative recovery.

Performance-based outcomes following patellar tendon repair in professional athletes

Objectives: There are limited data on the impact of a patellar tendon repair to a professional athlete's career. The purpose of this study was to determine differences return to play (RTP) rate, career length, and performance-based outcomes after a patellar tendon repair in professional athletes of four different sports.Methods: Participants met inclusion criteria if initial reports of the date and type of surgery were corroborated by at least two independent sources of information through a well-established protocol of public newspaper archives, team injury reports, and player profiles. Players with other concomitant injuries of the knee or treated nonoperatively were excluded. One hundred and three athletes across professional baseball, basketball, American football, and soccer athletes were identified and met inclusion criteria. RTP rate, career length, and sports-specific performance statistics (i.e. player efficiency rating (PER) for professional basketball players) before and after surgery were collected for each athlete.Results: Seventy-nine (76.7%) professional athletes successfully RTP. American football athletes had the lowest RTP rate and the largest drop in performance in post-operative season 1 (P < 0.001). These athletes also experienced the shortest adjusted career lengths (P = 0.003) compared to players in the other sports. Basketball athletes played significantly less games through post-operative seasons 1 to 3 (P < 0.05). Soccer athletes had less goals and assists per game and played fewer games (P < 0.05) in post-operative season 1 that recovered to baseline by seasons 2 and 3.Conclusion: A patellar tendon rupture is a potentially devastating injury for the professional athlete. American football players appeared to have the worst postoperative outcome with the lowest RTP rate and a most significant decrease in performance in the first postoperative season. This procedure also had a significant short-term impact on soccer athletes who sustained decreases in short-term game performance. These findings are likely explained by the unique physical demands imposed by each sport.

Comparison of a modified technique with conventional tension-band using Cable Grip System for comminuted patella fractures

INTRODUCTION

Treatment of comminuted patella fractures with tension band has resulted in impaired functional outcomes because the relationship between tension band and the tendons is always underestimated. We developed a modified enlacement (ME) technique to better place the tension-band under the quadriceps and patellar tendons and close to the patella. The study aimed to compare the ME with conventional enlacement (CE) technique regarding recovery of knee function.

PATIENTS AND METHODS

51 patients with comminuted patella fractures operated between January 2012 and December 2016 were reviewed retrospectively. 22 patients in the ME group (9 males and 13 females) with a mean age of 51.3 years, 29 patients in the CE group (16 males and 13 females) with a mean age of 47.1 years. ROM was measured at postoperative intervals of 1, 2, 4, 12, and 48 weeks; Knee function was evaluated using the Rasmussen scores at 4, 12, and 48 weeks postoperative.

RESULTS

There was no difference (P = 0.082) regarding the fracture healing time between the two groups. Patients with the ME technique had clinically and statistically significantly higher ROM recovery throughout the study period (P < 0.001) with an earlier recovery. The Rasmussen scores also demonstrated significant improvements in patients with ME technique than CE group at all time-points (P < 0.05). Three patients in the CE group had migration of K-wires, with no migration observed in the ME group.

CONCLUSION

The ME technique enables improved clinical outcomes and functional performance for the treatment of comminuted patella fractures.

Reconstruction of knee extensor with patellar tendon autograft following intraoperative radiotherapy

BACKGROUND

Patellar tendon autograft after intraoperative extracorporeal radiotherapy has been used for reconstruction of the extensor mechanism following limb-sparing wide tumor resection around the knee. The purpose of this study was to determine the clinical outcome of this reconstruction technique.

METHODS

We retrospectively reviewed six consecutive patients with peripatellar tendon and proximal tibial sarcoma who underwent reconstruction of the knee extensor mechanism. The resection area was planned to be contained with the patellar tendon in order to obtain a wide margin. First, the patella was osteotomized at the midline, and the inferior half of patella, patellar tendon, and tibial tuberosity were excised en bloc. The resected segments were devitalized with intraoperative extracorporeal radiotherapy and reimplanted into the original site. A follow-up evaluation included an assessment of the range of motion, extensor lag, the International Society of Limb Salvage score, and complications.

RESULTS

Six patients were followed up for 121-270 months. One patient underwent an additional reconstruction with total knee arthroplasty due to a collapse of the tibial subchondral bone. A supracondylar fracture of the femur occurred in two patients, and a delayed union of the osteosynthesis site of the tibial shaft was observed in one patient. At the latest follow up, extensor lag had a median of five degrees, and International Society of Limb Salvage scores had a median of 83%. No local recurrence or rupture of the patellar tendon was observed.

CONCLUSIONS

Reconstruction of the knee extensor mechanism using a patellar tendon treated with intraoperative radiotherapy is a reliable and successful method.

Quadriceps tendon vs. patellar tendon autograft for ACL reconstruction using a hardware-free press-fit fixation technique: comparable stability, function and return-to-sport level but less donor site morbidity in athletes after 10 years

INTRODUCTION

The use of quadriceps tendon-patellar bone (QTB) autograft for anterior cruciate ligament (ACL) reconstruction is gaining momentum. Yet, long-term results that compare this procedure with established methods are lacking. The aim of this study was to report and compare long-term results of ACL reconstruction using QTB autografts versus bone-patellar tendon-bone (BPTB) autografts, both anchored using a hardware-free press-fit fixation technique.

MATERIALS AND METHODS

60 athletes (Tegner score ≥6) with primary ACL rupture were prospectively randomized into two groups. 56 patients were evaluated after a mean duration of 12.2 ± 1.9 months (range 10-14) and 43 patients after 10.3 ± 0.2 years (range 10-11).

RESULTS

On final follow-up, 90% of patients scored very good and good results in the functional Lysholm score (mean 99 ± 7.1, range 74-100 points). Normal or almost normal IKDC score was reported by 84% of the patients (mean 97 ± 9.5, range 60-100 points). The activity level decreased in the Tegner score from median of 7 before injury to 6 after 10 years. The KT-1000 arthrometer showed a difference in the anterior translation of less than 3 mm (mean 1.0 ± 1.2, range - 1 to 5 mm) in 91% of the patients. Significant degeneration was radiologically detected in one patient per group. No tunnel widening was seen in any patient. Up to 97% of all patients were satisfied with the operative procedure. No significant differences were found in the mentioned parameters between the two groups and also in comparison with the 1-year results. The only significant difference was in the donor site morbidity. Significantly more patients in the BPTB group had complaints during kneeling both at 1 (p < 0.001) and 10 years (p = 0.019). Squatting was also subjectively more problematic in the BPTB group than in the QTB group both after 1 (p = 0.003) and 10 years (p = 0.046).

CONCLUSIONS

This study shows equally good functional, clinical and radiological long-term results for both hardware-free methods of ACL reconstruction. These results clinically confirm the safety of press-fit anchoring after 10 years. The failure rate in this study was very low, with only one re-rupture in 10 years. The increased donor site morbidity when using the BPTB autograft compared to the QTB autograft supports already reported data. It was also seen in this study for the implant-free press-fit techniques.

STUDY DESIGN

Prospective and randomized, level of evidence 2.

Successful management of unilateral congenital patellar tendon aplasia: case report

Anatomical variation is discovered frequently in humans, and much such variation in the musculoskeletal system has been reported. We present a rare case of unilateral congenital patellar tendon aplasia with concomitant apparent shortness of the bilateral halluces as a result of shortened first metatarsals as an anatomical variant.

Increased signal in the proximal patellar tendon: normal or pathologic?

OBJECTIVE

To determine the clinical significance of T2 signal hyperintensity in the proximal patellar tendon seen on MRI of the knee.

MATERIALS AND METHODS

MRIs of 100 patients who underwent MRI of the knee between 1 May 2018 and 15 July 2018 were retrospectively evaluated. All examinations were performed on 3-Tesla MRI scanners with a dedicated knee coil and in accordance with our institution's standard knee MRI protocol. The presence of increased T2 signal was assessed on both sagittal and axial T2-weighted fat-saturated images. The amount of increased signal in the proximal patellar tendon on T2-weighted images was characterized as: none, mild, moderate, or severe. A corresponding chart review of the referring physicians' notes was performed to determine the presence of clinical symptoms of patellar tendinopathy. Patellar tendinopathy was considered present if the clinical notes described tenderness on palpation of the inferior patellar pole, infrapatellar tenderness, or patellar tendinosis/tendinitis.

RESULTS

The majority (66%) of knee MRIs demonstrated the presence of increased T2 signal in the proximal patellar tendon. Only 4.5% of these patients had associated clinical findings of patellar tendinopathy.

CONCLUSION

Although increased T2 signal in the proximal patellar tendon is a common finding, only in rare cases are there associated clinical symptoms. Thus, increased T2 signal in the proximal patellar tendon may not be a pathological finding in the absence of clinical findings of patellar tendinopathy.

Fibroma of the patellar tendon sheath-a rare case in a young boy

Fibroma of the tendon sheath is a rare benign fibrocollagenous soft tissue tumor, arising predominantly from the synovium of tendon sheath. Fibromas occur most commonly in relation to the tendons of the fingers, hand, and the wrist. Fibromas related to large joints are rather rare and though amongst the large joints, the knee is a common site. Fibromas of the patellar tendon sheath, specifically, are very rare. To the best of our knowledge, only three cases of fibromas arising from the patellar tendon sheath have been reported in the relevant English medical literature. Herein we describe the fourth biopsy-proven case of fibroma of patellar tendon sheath in a 6-year-old boy.

Quantitative magnetic resonance imaging in patellar tendon-lateral femoral condyle friction syndrome: relationship with subtle patellofemoral instability

OBJECTIVE

To investigate the correlation of patellar tendon-lateral femoral condyle friction syndrome (PTLFCFS) with subtle patellofemoral instability to explore its pathogenesis.

MATERIALS AND METHODS

One hundred knees of 80 patients with PTLFCFS were analyzed retrospectively by retrieving magnetic resonance imaging (MRI) data over a 3-year period from our database. Seven quantitative parameters for evaluating patellofemoral stability were measured on MR images, including the Insall-Salvati ratio, tibial tuberosity-trochlear groove (TT-TG) distance, trochlear groove depth, medial trochlear/lateral trochlear length (MT/LT) ratio, medial trochlear/lateral trochlear height (MH/LH) ratio, lateral patellofemoral angle (LPA), and lateral trochlear inclination (LTI) angle. These patellofemoral parameters of the PTLFCFS group and the normal control group were compared (n = 88), and receiving-operator characteristic (ROC) curve analysis was conducted to determine the specificity and sensitivity of these parameters.

RESULTS

The trochlear depth, MT/LT, LPA, and LTI angle were significantly lower (p < 0.001) and the Insall-Salvati ratio was significantly higher (p < 0.001) in the PTLFCFS group. However, the TT-TG distance and MH/LH ratio showed no significant difference (p = 0.231 and 0.073 respectively). The area under the ROC curve of the Insall-Salvati ratio, trochlear depth, MT/LT, LPA, and LTI angle were 0.925, 0.784, 0.8, 0.731, and 0.675 respectively. The efficiency of the Insall-Salvati ratio was the highest among those five parameters.

CONCLUSION

This study verified the presence of subtle patellofemoral instability by measuring various patellofemoral parameters in patients with PTLFCFS. It confirmed that PTLFCFS is associated with subtle patellofemoral instability and could largely explain the pathogenesis of PTLFCFS.

Strain Ratio Measurements of Patellar and Achilles Tendons With Different Reference Regions in Healthy Volunteers

Strain ratio measurements of tendons vary because of the reference tissue selection. The main purpose of this study is to highlight, in detail, the numeric variability attributable to the use of various reference materials on strain ratio measurements of patellar and Achilles tendons. Measurements were performed at the proximal, middle and distal thirds of the patellar and Achilles tendons on the dominant site of healthy volunteers. A total of 3 references were used: the Hoffa's fat pad for the patellar tendon, the Kager's fat pad for the Achilles tendon, subcutaneous tissue and Aquaflex gel pads (Parker Laboratories, Fairfield, NJ, USA) for both tendons. Although the same methods were used by the same physician for each tendon site on repeated measurements, strain ratio values had numeric variability with various reference materials in each measurement. Therefore, comparison of numeric strain ratio results of various studies with various reference materials could confuse the clinical interpretations of these numeric data, and, using a reference material with standard stiffness like Aquaflex ultrasound gel pads, should be considered by verifying these results with further studies.