Patellar tilt does not affect patient reported outcomes after modern total knee arthroplasty

BackgroundThe focus of patella maltracking after total knee arthroplasty (TKA) has traditionally been on patella polyethylene damage and failure mechanisms rather than functional outcomes. The purpose of this study was to evaluate the effect of patellar tilt on patient reported outcomes (PROMS) after primary TKA performed with patellar resurfacing.MethodsA retrospective review using a single implant design was performed. Patella tilt was radiographically measured according to a standardized protocol. PROMS related to pain, function, and satisfaction were evaluated preoperatively and at minimum 1-year follow-up.ResultsA total of 468 TKAs were included for analysis. Mean age and BMI were 64 years and 35 kg/m²; respectively while 63% of patients were female. The median follow-up period was 12.7 months. Overall, patellar tilt was corrected from a median of 5.0 degrees preoperatively to a median of 3.0 degrees postoperatively. Preoperative, postoperative, and the change in patellar tilt had no significant effects on PROMS at minimum 1-year follow-up (p ≥ 0.092). Satisfaction in knee function while getting out of bed was higher for patients with approximately the same patellar tilt before and after TKA compared to patients with an increase in lateral patellar tilt (95% vs 80%, p = 0.025).ConclusionsThe range of patellar tilt studied in this cohort had little to no effect on PROMS. However, suboptimal patellar tracking may potentiate edge loading of the polyethylene and contribute to implant damage in the long-term. These results are helpful to focus efforts on the tibiofemoral articulation as the predominant determinant of patient outcomes.     

Patellar cartilage loss does not affect early outcomes of total knee arthroplasty performed without patella resurfacing

BackgroundThe aim of this study was to compare the outcomes and cost economics of TKA without patella resurfacing in patients with and without patellar cartilage loss.MethodsProspective case control study of 209 consecutive patients undergoing TKA without patella resurfacing. Patella cartilage status was documented intra-operatively: 108 patients had patella cartilage loss (mean age 70 ± 9.7, mean BMI 31 ± 6.2, 72 (67%) female) and 101 control patients did not (age 68 ± 9.2, BMI 31 ± 5.6, 52 (51%) female). The primary outcome measure was Oxford Knee Score (OKS) improvement at one year. Secondary outcomes included OKS, EQ-5D, anterior knee pain (AKP), Kujala scores and reoperation at 2–4 years. The cost to prevent secondary patella resurfacing was calculated.ResultsThere were more women in the patella cartilage loss group (67% Vs 51%, p = 0.037), but no other preoperative characteristics differed. There was no difference in OKS improvement between those with and without patella cartilage loss at 1 year (mean difference −1.03, −3.68 to 1.62 95%CI, p = 0.446) or 2–4 years (mean difference 1.52, −1.43 to 4.45 95%CI, p = 0.310). At 2–4 years there was no difference in AKP (14/87 with vs 17/80 without, p = 0.430) nor Kujala score (mean difference 2.66, −3.82 to 9.13 95%CI, p = 0.418). Routine patella resurfacing would have cost £58,311 to prevent one secondary resurfacing.ConclusionThere was no difference in OKS, anterior knee pain, reoperation or Kujala scores up to 2–4 years between patients with and without patellar cartilage loss following TKA without patella resurfacing. Resurfacing for this indication would not have been a cost effective intervention.     

Gender optimized patellar component designs are needed to better match female patellar anatomy

BackgroundAvoidance of both over-resection of the native patella, and over-stuffing of the patello-femoral joint are advocated to reduce the risk of patellar complications following patellar resurfacing. Female gender, due to thinner native patella, and use of patellar prostheses from one specific manufacturer that were thicker for comparable diameters than the patellar prostheses from a second manufacturer were hypothesized to be risk factors for these undesirable technical outcomes.MethodsA retrospective review was undertaken of 803 consecutive knee replacements, performed by one surgeon, during which the same patellar resurfacing technique had been used, but with two different patellar implant designs.ResultsFemale gender, and use of one specific design of patella prostheses were associated with both increased risk of patellar over resection to ≤ 13 mm residual patellar thickness, and creation of a patella construct that was thicker than the native patella (p < 0.001).ConclusionsPatellar prostheses design can contribute to compromises in surgical technique during patellar resurfacing in TKA in female patients with thinner patellae. Modifications to current patellar prosthesis dimensions may be considered to allow surgeons to more accurately resurface the thinner, native female patella.Level of EvidenceIII     

Patella related problems as common reason for revision of NexGen PS® total knee arthroplasty without patella resurfacing: An analysis of 5911 primary total knee arthroplasties registered in the Dutch Arthroplasty Register

BackgroundPatella resurfacing remains controversial in primary total knee arthroplasty (TKA). The aim of this study was to investigate if there was a difference in revision rate and reason for revision within 8 years after single brand primary cemented TKA with or without patella resurfacing, using data from the Dutch Arthroplasty Register.MethodsAll primary TKA surgeries with a posterior stabilized cemented primary NexGen®, between 2010 and 2013 with diagnosis osteoarthritis were analyzed (n = 5911). Multivariate cox regression analyses were performed to analyze differences in revision rate between TKA with or without patella component, and was adjusted for age and previous surgery.ResultsOf 5911 TKA surgeries, 4795 were performed without patella resurfacing (81.1%) and 1116 with patella resurfacing (18.9%). There was a significant difference in patellar problems as reason for revision between patients after primary TKA with patella resurfacing (9.3%) and without patella resurfacing (29.9%) (p = 0.01). This was mostly caused by patellar pain (28.0%). There was no significant difference in cumulative revision rate within between TKA with patella resurfacing and without patella resurfacing.ConclusionIn conclusion, 30% of patients who need revision surgery after TKA using NexGen® PS without patella resurfacing the reason for revision is patella related problems, compared to 9% after TKA NexGen® PS with patella resurfacing. There was no difference in cumulative incidence of revision after primary surgery of all TKA’s using NexGen® PS with or without patella. To reduce the probability of reoperation for patella related problems, our data suggest the patella should be resurface during primary TKA.     

Biomechanical assessment of patellar tendon advancement in patients with cerebral palsy and crouch gait

BackgroundPatellar height is a valuable measure to evaluate the effect of patellar tendon advancement (PTA) on knee function. In the literature, there is no validated procedure to measure the patellar height. In this study we aimed to (1) determine the patella position through musculoskeletal modeling, (2) investigate the effects of two surgical procedures applied for PTA, and (3) assess the effect of PTA in combination with single-event multilevel surgery (SEMLS) on the knee kinematics of patients with cerebral palsy (CP) and crouch gait.MethodThree-dimensional gait and X-ray data of children with CP and crouch gait were retrospectively analyzed if they had received a SEMLS in combination with PTA (PTA group, n = 18) or without PTA (NoPTA group, n = 18). A computational musculoskeletal model was used to quantify patella position, knee extension moment arm, and knee kinematics pre- and postoperatively.ResultsPatellar height significantly decreased in the PTA group (P = 0.004), while there was no difference in the NoPTA group (P > 0.05). The bony procedure for PTA provided a better Insall–Salvati ratio than the soft tissue procedure. The peak knee extension moment arm significantly increased in the PTA group (P = 0.008). In terms of postoperative knee joint kinematics, the PTA group was closer to typically developed children than the NoPTA group.ConclusionMusculoskeletal modeling was found to be an effective tool for the determination of the patellar height. PTA improved the patella position, knee extension moment arm, and knee kinematics and was an effective procedure for the surgical management of crouch gait in patients with CP.     

Wiberg Type III patellae and J-sign during extension compromise outcomes of total knee arthroplasty without patellar resurfacing

BackgroundUnderstanding the risk factors associated with postoperative pain and worse outcome can guide surgeons on whether primary patellar resurfacing is warranted during total knee arthroplasty (TKA). The purpose of this study was to determine whether clinical scores and pain after TKA without patellar resurfacing are correlated with patellar shape and postoperative patellar position and kinematics.MethodsRadiographs as well as anterior knee pain according to the Visual Analogue Scale (pVAS) were collected pre- and postoperatively for 100 knees aged 68 ± 7.7 years that received uncemented TKA without patellar resurfacing. At a minimum follow-up of 12 months the Forgotten Joint Score (FJS), the Oxford Knee Score (OKS) as well as the flexion range of motion and the presence of J-sign during active extension were recorded. Uni- and multivariable linear regression analyses were performed to determine associations between the collected clinical scores and patient demographic and radiographic data.ResultsPostoperative OKS (79 ± 14.4) was worse for Wiberg Type III patellae (β = − 11.4, P = .020, compared with Type II). Anterior pVAS (2 ± 2) was greater in knees with J-sign during extension (β = 2.8, P < .001). None of the other radiographic measurements (patellar tilt, congruence angle and lateral patellar displacement) were correlated with postoperative OKS or anterior pVAS.ConclusionIncongruent patellar shape (Wiberg Type III) is associated with worse clinical scores, and abnormal kinematics (J-sign) with increased pain after TKA without patellar resurfacing. The authors therefore recommend routine resurfacing for Wiberg Type III patellae, though further studies are required to confirm whether resurfacing truly improves clinical scores and pain in this subgroup.     

Usefulness of gait parameters obtained from inertial sensors attached to the lower trunk and foot for assessment of gait performance in the early postoperative period after total knee arthroplasty

BackgroundThis study was performed to (i) compare gait parameters obtained from inertial sensors attached to the lower trunk and foot between patients in the early postoperative period after total knee arthroplasty (TKA) and healthy age- and sex-matched controls and (ii) elucidate the association between the gait parameters and patient-reported outcome measures (PROMs).MethodThe gait performance of 19 patients who had undergone TKA was assessed using inertial sensors and PROMs obtained from the Knee Injury and Osteoarthritis Outcome Score (KOOS) 1 week before hospital discharge. The patients walked along a 15-m walkway and we calculated the following gait parameters: walking speed, coefficient of variation (CV) of stride time, unbiased autocorrelation coefficient (AC), harmonic ratio (HR), and symmetry index (SI). The same gait parameter data from 19 age- and sex-matched healthy adults (controls) were obtained from our past study.ResultsThe TKA group demonstrated slower walking speed, larger CV of stride time, lower HR in all three directions, lower AC in the vertical direction, and higher SI in the vertical direction than the healthy control group (all p < 0.05). Correlation analysis revealed that the SI in the anteroposterior direction was significantly correlated with the KOOS symptoms subscore and ADL subscore (p < 0.05).ConclusionsPatients in the early postoperative period after TKA exhibited worse gait performance as assessed by inertial sensors compared with healthy controls. Gait symmetry was correlated with PROMs. These results indicate the usefulness of assessing gait parameters after TKA.     

Perioperative duloxetine administration reduces pain after high tibial osteotomy and non-steroidal anti-inflammatory administration: A prospective,controlled study

BackgroundPostoperative pain management is essential for patient satisfaction; however, no reports have described the effect of perioperative duloxetine administration on the postoperative pain management following knee surgery. This study aimed to determine whether perioperative duloxetine administration reduces pain following high tibial osteotomy.MethodsIn this prospective clinical trial, 35 and 33 patients receiving (40 mg/day) and not receiving duloxetine (control), respectively were enrolled. The knee pain and quality of recovery were evaluated using the numeric rating scale (NRS) scores, the frequency of analgesic drugs used, and patient-reported outcome measures, including the NRS score at rest and the Knee Injury and Osteoarthritis Outcome Score (KOOS), were compared between the groups.ResultsThe NRS scores of the duloxetine group (D) were significantly reduced compared with those of the control group (C) on postoperative day 1 (D:3.8 vs C:5.1, p = 0.022), day 7 (D:2.1 vs C:2.9, p = 0.021), and day 14 (D:1.6 vs C:2.9, p = 0.001). Non-steroidal anti-inflammatory drug administration was significantly lower in the duloxetine group than in the control group (p < 0.001). Although the KOOS score was not significantly different in several subcategories at the pre- and postoperative time-points, the Function in Sport subcategory of the KOOS was significantly improved in the duloxetine group compared with that in the control group at 3 months postoperatively (p < 0.05).ConclusionPerioperative use of duloxetine from 2 weeks before surgery to 2 weeks after surgery is advantageous in perioperative pain management and KOOS improvement following high tibial osteotomy.     

Treatment of osteochondritis dissecans of the patella in adolescents with nanofractured autologous matrix-induced chondrogenesis (NAMIC): A report of five cases

PurposeOsteochondritis dissecans (OCD) of the patella is a very rare affliction. The aim of this case series is to evaluate the effectiveness of the Nanofractured Autologous Matrix-Induced Chondrogenesis (NAMIC) technique for the treatment of OCD in young adults.MethodsFive consecutive patients with patellar osteochondral lesions treated with NAMIC were prospectively studied. There were 4 males and 1 female with a mean age of 15.2 years, ranging from 12 to 18 years. Clinically, they presented pain when going up and down stairs or squatting, effusion, swelling and functional limitation. The International Cartilage Repair Society (ICRS) grade was III in 4 patients and IV in 1 patient. Patients were functionally evaluated with the Lysholm knee score, the Tegner Activity Score (TAS) and the Knee Injury and Osteoarthritis Outcome Score (KOOS) and radiologically using the Magnetic resonance Observation of Cartilage Repair Tissue (MOCART) score.ResultsAll the scores significantly improved two years after surgery with respect to pre-operative values (Lysholm score from 63.8 ± 3.9 before surgery to 91 ± 3.2 at 2 years; Tegner activity score from 3.6 ± 0.5 to 8.2 ± 0.8 and the KOOS score from 45.2 ± 2.6 to 91.2 ± 2.4). Both the X-rays and the Magnetic Resonance Imaging (MRI) showed good joint regularity with an average MOCART of 80 ± 7.1/100.ConclusionsTreatment of juvenile patellar osteochondritis dissecans with the NAMIC technique seems to be a reliable technique in the short term to restore the patella joint surface and obtain good functional results.     

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

BackgroundPatellar 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.MethodsA 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.ResultsEleven 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.ConclusionsPatellar 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.     

Aseptic versus septic revision total knee arthroplasty: Patient satisfaction,outcome and quality of life improvement

We prospectively compared the clinical outcomes and patient satisfaction rates of aseptic (n = 30) versus septic revision TKA (n = 15) at a mean follow-up of 40 months. We hypothesized that the clinical results of septic revision TKA would be inferior to aseptic revision TKA. The indication for revision in aseptic group was stiffness in 11 patients, aseptic loosening in 13, patellar loosening or maltracking in 6 patients. Patients operated for infection had better post-operative Knee Society Scores (KSS), Function Scores and SF-36 Mental Scores than aseptic group but there were no significant differences in the satisfaction rates. Patients operated for infection had more improvement in their KSS (p = 0.004) and Function Scores (p = 0.02) than patients revised for stiffness. Moreover, patients operated on for patellar problems had higher satisfaction rates than patients revised for stiffness (p = 0.01) or aseptic loosening (p = 0.01). Thus, patients undergoing septic revision TKA had better outcomes compared to those with aseptic revision TKA. However, in the aseptic group, revision TKA for stiffness was associated with the poorest outcomes. The indication for aseptic revision is an important variable when discussing treatment and outcome with patients.     

Total knee arthroplasty in post-traumatic osteoarthritis is more challenging,but results in similar patient satisfaction – An analysis of 1646 cases

BackgroundPatients with post-traumatic osteoarthritis (PTOA) present a variety of technical challenges to surgeons. Surgical parameters, complication rates and patient-reported outcomes (PROs) have been reported as detrimental in total knee arthroplasty (TKA) for PTOA. The purpose of this study was to compare these variables and satisfaction with the results of TKA in patients with post-traumatic osteoarthritis with a matched-pair cohort of primary osteoarthritis (POA).MethodsA registry-embedded prospective case–control study was performed. Of a total of 1646 TKAs, 155 were performed due to PTOA between 2012 and 2019. One-hundred and thirty-six could be one-to-one propensity score-matched to patients with POA undergoing primary TKA based on similar patient demographic variables. Outcomes investigated included operation time, estimated blood loss, types of implants, postoperative complications and PROs pre- and 1 year postoperatively as well as satisfaction with the results of surgery. Sub-cohort analysis was performed for patients with prior fracture and soft tissue trauma, respectively.ResultsSurgical parameters were significantly different in disadvantages of PTOA: operation time (P < 0.001), estimated blood loss (P < 0.001), blood transfusions (P = 0.039), type of implants (P < 0.001). Manipulation under anaesthesia (MUA) was necessary more often in the PTOA fracture group (odds ratio 5.01, (95% confidence interval 1.04; 24.07). PRO demonstrated no substantial differences after 1 year. Satisfaction with the results of TKA was as equally high in all cohorts.ConclusionsThis study demonstrated that TKAs in patients with PTOA require higher surgical effort but can result in similar PROs and satisfaction compared to POA, regardless of the underlying trauma.     

The successful migration of total joint arthroplasty from the hospital inpatient to outpatient ASC setting

BackgroundThis study was undertaken to analyze the clinical results and complication rate of patients undergoing outpatient total joint arthroplasty by a single orthopedic group. All surgeries were performed in the practice-owned ambulatory surgery center (ASC).MethodsAll patients indicated for outpatient total joint arthroplasty from 2016-2019 with complete pre and post-operative patient reported outcomes were enrolled in the study including hip, knee and partial knee replacements. Patient reported outcomes including HOOS, KOOS and VR-12 were collected at six months. Patient complication and satisfaction data was also collected.ResultsThere were 1007 patients enrolled in the study. At six months, THA HOOS and VR-12 scores improved to 82.2 and 54.5/45. TKA KOOS and VR-12 scores improved to an average of 74.3 and 54.0/43.6. At six months, UKA scores improved to an average of 73.6 and 55.1/41.2. All HOOS, KOOS and VR-12 PCS scores improvements were statistically significant (p < 0.001) and met MCID thresholds. A separate cohort of 1898 regionally tracked cases with comprehensive global complication data exhibited 111 complications (unplanned post-operative events generating a medical expense) including manipulation 13 (0.68%), DVT/PE 4 (0.2%), medical 45 (2.4%), wound 8 (0.4%), infection 8 (0.4%). Sixty-six outpatient cases (3.5%) experienced clinical complications requiring some form of additional treatment.ConclusionOutpatient joint arthroplasty performed in the ASC is safe and effective in appropriately selected patients with complication rates that compares favorably to inpatient procedures.     

Early postoperative predictors of satisfaction following total knee arthroplasty

BackgroundDespite the excellent total knee arthroplasty (TKA) results reported using traditional outcome measures, dissatisfaction rates of up to 30% are reported following surgery. Although several preoperative factors have been identified as possible predictors of satisfaction, there is conflicting evidence. Identification of dissatisfaction in the early postoperative assessment may therefore be an alternative consideration.MethodsWe examined the relationship between 12-month satisfaction, and early post-operative outcomes in a cohort of 486 TKA patients. Preoperative, and postoperative outcome measures at 3- and 12-months (Oxford knee score, pain score, SF12, and knee motion), were analysed and compared between patients who were satisfied and dissatisfied at 12-months following TKA. Mean scores, and postoperative change in scores were calculated. Postoperative outcomes were examined for correlation with satisfaction, and multivariate logistic regression models used to identify potential predictors of dissatisfaction.ResultsOverall satisfaction was 77.0%. No preoperative differences were observed between groups. Dissatisfaction was associated with worse postoperative status across all outcome measures (p < 0.001), except the 3-month SF12-physical component (p = 0.052). Dissatisfied patients demonstrated minimal further improvement or even worsening of outcome scores between 3- and 12-months postoperatively (p < 0.02). Both the 3-month OKS (OR = 1.15, p < 0.001), and knee flexion (OR = 1.03, p = 0.009) were significant predictors of subsequent 12-month satisfaction.ConclusionsDissatisfaction following TKA is associated with worse outcomes as early as 3 months following surgery, with minimal further improvement subsequently achieved at 12-months. Early postoperative assessment following TKA should therefore be considered, including clinical assessment, to identify those patients at risk of dissatisfaction.     

Does malrotation of components correlate with patient dissatisfaction following secondary patellar resurfacing?

BackgroundThe aim of our study was to identify whether there was any correlation between the outcome of secondary patellar resurfacing and malrotation of either the femoral or tibial component.MethodsWe identified patients that underwent secondary patellar resurfacing following previous primary total knee arthroplasty (TKA) at a single, large orthopaedic department. Patients were reviewed for range of movement, satisfaction, health status and knee function. CT scanning was performed, assessing rotational alignment of the components.ResultsTwenty-one patients (23 knees) were reviewed. Nine out of 21 (39%) were satisfied while 14 (61%) remained dissatisfied after the secondary patellar resurfacing. There were no complications after the secondary procedure. All knees were internally rotated. The mean femoral internal rotation in the satisfied group was 0.92°, and in the dissatisfied group was 2.88° of internal rotation. In the dissatisfied group eight out of 14 TKAs were in > 3° femoral internal rotation compared with only one in nine TKAs in the satisfied group (p < 0.05).ConclusionsInvestigation for malrotation should be considered in patients with post-operative pain, especially anteriorly, causing significant dissatisfaction amongst patients following TKA. This is especially true if the patella has not been primarily resurfaced and secondary resurfacing is being considered. Patients with more than 3^° of femoral internal rotation undergoing secondary patella resurfacing should be warned of the possibility of a poor outcome. It may well be that if the underlying problem is component malrotation, revision knee replacement may lead to a more satisfactory outcome than secondary resurfacing alone.Level of EvidenceLevel of Evidence III.     

The relationship between length of the iliotibial band and patellar position in Asians

BackgroundTightness of the iliotibial band (ITB) has been documented as a major factor in lateral patellar translation because the ITB inserts into the lateral border of the patella through the iliopatellar band. The aim of this study was to compare the patella–condyle distance (PCD) between subjects with and without ITB tightness. We also investigated the relationship between ITB length and lateral patellar translation in hip adduction.MethodsIn 40 healthy volunteers, we measured the ITB length with Ober's test and the PCD at two hip positions (neutral and 20° adduction) using ultrasonography. Lateral patellar translation in hip adduction was calculated by subtracting the PCD at the adduction position from the hip neutral position.ResultsTwenty-three of the 40 subjects had ITB tightness; these subjects had a significantly laterally positioned patella at 20° adduction of the hip (p = 0.044). Patients with ITB tightness also had greater lateral patellar translation in hip adduction than patients without tightness (p = 0.000). The ITB length was moderately correlated with the PCD at 20° adduction of the hip (r = 0.427, p = 0.042) and strongly negatively correlated with lateral patellar translation (r = − 0.717, p < 0.000).ConclusionsThese findings support the hypothesis that increasing ITB tension has a significant effect on the position of the patella and therefore affects translation of the patella. However, these findings do not indicate that ITB length is the only cause of lateral patellar translation; further studies are needed to assess the relative importance of different factors that could affect patellar position.     

Percutaneous reconstruction of patellar tendon using semitendinosus tendon in chronic patellar tendon injury — case series and outcome

BackgroundChronic patellar tendon injuries are rare. Patients with these debilitating injuries present with extension lag and quadriceps atrophy. Diagnosis is usually made on a clinical background. Various methods of reconstruction of torn patellar tendon have been described and the ideal method of treatment is a matter of debate.MethodsWe retrospectively reviewed the medical records of nine patients with chronic patellar tendon injury that came to us between June 2006 and July 2012. In all patients, the patellar tendon was reconstructed percutaneously using semitendinosus tendon. Picrusting of quadriceps was required in two patients to pull the patella down.ResultAverage follow-up was 4.5 years. At final follow-up Lysholm score, Siwek and Rao grading were good to excellent in all patients, and at 12 months, all patients showed quadriceps strength 80% or more of opposite quadriceps.ConclusionPercutaneous reconstruction of the patellar tendon in chronic patellar tendon injury using semitendinosus tendon gives excellent result. Picrusting of quadriceps along with lateral release may be required to pull the patella down.Level of evidenceLevel IV.     

Patient-reported outcomes of 7133 distal femoral,patellar, and proximal tibial fracture patients: A national cross-sectional study with one-, three-, and five-year follow-up

BackgroundFew studies have described patient-reported outcome measures (PROMs) in knee fracture patients. We reported knee-specific and generic median PROM scores after knee fracture and identified risk factors for poor outcome defined by low median PROM scores.MethodsIn a Danish cross-sectional study of 7133 distal femoral, patellar, and proximal tibial fracture patients during 2011–2017, OKS, FJS-12, EQ5D-5L Index, and EQ5D-5L Visual Analogue Scale (VAS), were collected electronically (response rate 53%; median age 60; 63% female). Poor outcome was defined as score lower than median PROM score. Poor outcome risk factors were estimated as odds ratios from binary logistic regression models.ResultsAt 0 to one year after knee fracture, median PROM scores were 31 (OKS), 27 (FJS-12), 0.50 (EQ5D-5L Index), and 74 (EQ5D-5L VAS). At > 5 years after knee fracture, median OKS score was 40, median FJS-12 score was 54, median EQ5D-5L Index was 0.76, and median EQ5D-5L VAS score was 80. Age > 40 years had higher odds for poor OKS and FJS-12 scores at short- and long-term follow-up after knee fracture. Comorbidity burden, distal femoral fracture, and treatment with external fixation and knee arthroplasty were risk factors for poor outcome at long-term follow-up, for all four PROMs.ConclusionsAlthough knee fracture patients have relatively high knee function and quality of life, their ability to forget about the knee joint after knee fracture is compromised. We identified several important risk factors for poor outcome measured by PROMs at different follow-up periods following knee fracture, which will help direct future quality-improvement initiatives.     

Clinical outcomes of medial patellofemoral ligament reconstruction using FiberTape and knotless SwiveLock anchors

BackgroundWe aimed to prospectively investigate the clinical outcomes of medial patellofemoral ligament (MPFL) reconstruction using polyester high-strength suture tape with knotless anchors.MethodForty-three patients (65 knees) were followed for at least 1 year postoperatively, with 27 patients (43 knees) followed for 2 years postoperatively. All patients underwent MPFL reconstruction using polyester high-strength suture tape (FiberTape®; Arthrex) with knotless anchors (SwiveLock®; Arthrex). Repeated dislocation and residual patellar apprehension signs were recorded, and congruence and tilting angles were measured. Changes in Knee Injury and Osteoarthritis Outcome Scale (KOOS) scores and their associations with the preoperative tibial tubercle–trochlear groove (TT-TG) distance were analyzed.ResultsNo repeat dislocations (0%) were observed. One (2.4%) residual positive patellar apprehension sign was noted. The mean tilting angle decreased from 24.8° to 10.7° (P < 0.001), and the mean congruence angle decreased from 24.9° to 4.3° (P < 0.001). At 2 years follow up, all KOOS subscales had improved: pain (92.0 ± 12.9), symptoms (90.2 ± 11.9), activities of daily living (95.7 ± 7.3), sports activity (85.7 ± 16.9), quality of life (87.7 ± 12.9), and patellofemoral (89.0 ± 9.6) outcomes. KOOS subscale scores improved regardless of the preoperative TT-TG distance (21.1 ± 3.5 mm; range, 13.8–29.9 mm).ConclusionsMPFL reconstruction using FiberTape and knotless SwiveLock anchors was performed without sacrificing autologous tissue. No recurrent patellar dislocation was observed during the 2-year follow up period. All KOOS subscale scores improved using FiberTape and SwiveLock anchors in MPFL reconstruction.     

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

BackgroundThe aim of this study was to evaluate the length and elasticity of the patellar tendon after open-wedge high tibial osteotomy (OWHTO).MethodsThis 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.ResultsThe 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.ConclusionThe patellar tendon seems to be shortened and thickened, with reduced stiffness after OWHTO. The ultrasound parameters are also associated with functional outcomes.