Short-term results of tibial interference screw fixation for transtibial medial meniscus posterior root pull-out repair.

Background: To evaluate the technique of transtibial pull-out repair with tibial interference screw fixation for medial meniscus posterior root (MMPR) tear by reporting on short-term outcomes and complications. Methods: All MMPR repairs performed between January 2019 and August 2021 (n = 70) were retrospectively screened regarding demographic data and surgical parameters. The patients were questioned for performed revision surgery, symptoms and complications. The Numeric Rating Scale (NRS) for pain, Lysholm Knee Score and International Knee Documentation Committee Subjective Knee Form (IKDC) questionnaires were used to evaluate clinical outcome. In cases of revision surgery for re-tear the mode of failure was intraoperatively classified (patients with re-tear were excluded from the clinical follow-up examination). The influence of demographic and treatment parameters (surgical and rehabilitation) on the incidence and mode of re-tear and clinical scores was evaluated. Results: After 2.3 ± 0.7 years, 62 patients (88.6 %) were available for follow-up. There were no direct intra- or postoperative complications. No revision was performed due to symptoms related to the tibial fixation material. The mean surgery time was 33.5 ± 10.8 min. The overall re-tear rate was 17.7 % (11 patients) of whom 10 were treated surgically and one conservatively. Primary mode of failure was suture cut-out from the meniscus (70 %). The NRS, Lysholm Knee Score and subjective IKDC were obtained in 38 patients and improved from 6.8 ± 2.4, 40.1 ± 23.9 and 32.8 ± 16.3 to 2.2 ± 2.2, 80.5 ± 16.3 and 63.0 ± 13.9, respectively (all p < 0.001). No influence was observed from demographic and treatment parameters on re-tear rates or clinical Scores. Conclusions: Tibial interference screw fixation is a fast and promising technique for MMPR transtibial pull-out repair. In the presented technique, utilizing non-absorbable locking sutures alongside tibial interfenrence screw fixation, the primary mode of failure was suture cut-out from the meniscus.

Effect of Anterior Tibial Closing Wedge Osteotomy on Coronal Tibial Alignment in Relation to Preoperative Medial Proximal Tibial Angle and Wedge Height.

BACKGROUND: The posterior tibial slope has been identified as an anatomic risk factor for anterior cruciate ligament insufficiency and reruptures after anterior cruciate ligament reconstruction. Anterior tibial closing wedge osteotomy for correction of sagittal plane deformities has the potential to cause an unintended change in coronal plane alignment. PURPOSE: To evaluate the effects of anterior tibial closing wedge osteotomies for correction of posterior tibial slope on coronal plane alignment using an infratuberosity surgical approach and to identify predictive factors for a change in medial proximal tibial angle (MPTA). STUDY DESIGN: Case series; Level of evidence, 4. METHODS: This study reports on retrospectively obtained data from radiographic measurements of 38 anterior tibial closing wedge osteotomies. All patients underwent revision anterior cruciate ligament reconstruction and had undergone ≥1 previous anterior cruciate ligament reconstruction. In all patients, an infratuberosity approach was used with angular stable plate fixation. Pre- and postoperative radiographs were examined retrospectively to detect changes in the sagittal and coronal plane alignment (posterior tibial slope and MPTA). A multivariate regression analysis was used to identify predictors for a change in MPTA. RESULTS: The study group consisted of 14 women and 24 men whose mean ± SD age at the index procedure was 31.6 ± 8.7 years (range, 17-51 years). Posterior tibial slope decreased significantly (by 7.2° ± 2.3°; P < .001) from 14.6° ± 2.0° preoperatively to 7.4° ± 2.1° postoperatively. MPTA decreased significantly by 1.3° ± 1.5° (P = .005) from pre- to postoperative measurement. Mean wedge height was 9.3 ± 1.1 mm. A lower preoperative MPTA (coefficient = 0.32; P = .017; 95% CI, 0.06-0.59) and larger wedge height (coefficient = 0.48; P = .029; 95% CI, 0.05-0.9) were significant predictive factors for a decrease in MPTA. CONCLUSION: Anterior tibial closing wedge osteotomy for posterior tibial slope reduction resulted in a slight but significant decrease of the MPTA in the coronal plane. These changes were dependent on the preoperative MPTA and the wedge height.

High prevalence of increased posterior tibial slope in ACL revision surgery demands a patient-specific approach.

PURPOSE: To determine the prevalence of an "increased posterior tibial slope (PTS)" (PTS ≥ 12°) in a population with one, two or ≥ three anterior cruciate ligament (ACL) graft insufficiencies. Furthermore, to investigate whether the prevalence of an increased PTS and the absolute PTS increases with an increasing number of ACL graft insufficiencies, as well as to determine the survival time of the first ACL graft. METHODS: Patients diagnosed with an ACL graft insufficiency between January 2021 and March 2022 were included. The PTS was measured using the proximal anatomical tibial axis on long lateral knee radiographs. Patients were divided into 3 groups depending on the number of ACL graft insufficiencies: group A (1 graft insufficiency), group B (2 graft insufficiencies) and group C (≥ 3 graft insufficiencies). The prevalence of increased PTS and absolute PTS between groups was compared alongside the survival of the first ACL graft between patients with or without increased PTS. RESULTS: Two-hundred and six patients (147 males/59 females) met the inclusion criteria. 73 patients showed an increased PTS [prevalence 35% [95% confidence interval (CI) (29%; 42%)]. 155 patients were found in category A, 42 patients in B and 9 patients in C. The prevalence of increased PTS for group A, B and C was, 32% [95% CI (25%; 40%)], 38% [95% CI (23%; 53%)] and 78% [95% CI (51%; 100%)], respectively. The prevalence of increased PTS and mean PTS did not increase significantly between group A and B. However, both parameters increased significantly between group A and C, and group B and C (p < 0.05). The survival time of the first ACL graft in patients with or without an increased PTS was 3 (interquartile range (IQR) 5) and 6 years (IQR 9), respectively (p < 0.05). CONCLUSION: There is a 35% prevalence of increased PTS in the studied ACL graft insufficient patient cohort. The survival of the first ACL graft is shorter in patients with an increased PTS. Surgeons should be aware of the high prevalence of increased PTS when consulting patients for revision ACL reconstruction as it is an important risk factor for recurrent instability.

The Patellar Instability Probability Calculator: A Multivariate-Based Model to Predict the Individual Risk of Recurrent Lateral Patellar Dislocation.

BACKGROUND: Predicting the risk of recurrence is of great interest when counseling patients after primary lateral patellar dislocation (LPD). PURPOSE: To investigate a multivariate model to predict the individual risk of recurrent LPD. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: The study population included patients with primary LPD, knee imaging, and a minimum 2-year follow-up after nonoperative treatment. Data including patient characteristics and anatomic patellar instability risk factors were collected retrospectively from 7 national study centers. Bivariate and multivariate regression analyses were carried out to identify risk factors for recurrent LPD and to generate an accuracy-optimized model for out-of-sample prediction. RESULTS: In total, 115 of 201 patients (57%) experienced recurrent LPD within 2 years after primary LPD. Age ≤16 years at primary LPD (odds ratio [OR], 5.0), history of contralateral instability (OR, 2.4), and trochlear dysplasia (Dejour type B-D: OR, 2.5; lateral trochlear inclination ≤12°: OR, 2.7) were significant risk factors for recurrent LPD (P < .05). The prediction accuracy including these 3 risk factors was 79%. Patella alta, an increased tibial tubercle to trochlear groove distance, and patellar tilt had neither an association with increased recurrence rates nor an influence on prediction accuracy of recurrent LPD. CONCLUSION: Young age and trochlear dysplasia are major risk factors for early recurrent LPD. A multivariate model including age at primary LPD, lateral trochlear inclination, and history of contralateral LPD achieved the highest prediction accuracy. Based on these findings, the patellar instability probability calculator is proposed to estimate the individual risk of early recurrence when counseling patients after primary LPD.

Midterm Results After Isolated Medial Patellofemoral Ligament Reconstruction as First-Line Surgical Treatment in Skeletally Immature Patients Irrespective of Patellar Height and Trochlear Dysplasia.

BACKGROUND: Medial patellofemoral ligament reconstruction in skeletally immature patients who experience lateral patellar dislocation has been reported to yield good results. Whether bony abnormalities such as patellar height and trochlear dysplasia should be addressed additionally is a topic of discussion. PURPOSE: To evaluate patient-reported outcomes and redislocation rates after isolated medial patellofemoral ligament reconstruction as first-line surgical treatment for lateral patellar dislocation in skeletally immature patients. Further, to analyze epidemiological, intraoperative, and radiographical factors influencing redislocation and clinical outcome. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Prospectively collected data were retrospectively analyzed for adolescent patients younger than 16 years who underwent medial patellofemoral ligament reconstruction between 2014 and 2018. Inclusion criteria were isolated medial patellofemoral ligament reconstruction with gracilis tendon and availability of accurate pre- and postoperative radiographs with the presence of open physes. The patients were questioned regarding further surgery, redislocation, and clinical outcomes using the Tegner Activity Scale, International Knee Documentation Committee (IKDC) Subjective Knee Form, Lysholm score, and Kujala score. The influence of diverse epidemiological, intraoperative, and radiographical parameters on the redislocation rates and clinical outcome was analyzed. RESULTS: A total of 54 medial patellofemoral ligament reconstructions (49 patients) met the inclusion criteria. After 4.3 ± 1.7 years (range, 2.0-7.3 years), 45 reconstructions (83.3%) in 41 patients were available for follow-up. The distribution of trochlear dysplasia was as follows: type A and B, 19 cases (42.2%) each; type C, 6 cases (13.3%); and type D, 1 case (2.2%). Patellar redislocation occurred in 3 patients (6.7%). The mean Tegner, subjective IKDC, Lysholm, and Kujala scores at follow-up were 6.3 ± 1.6 (range, 3-9), 93.6 ± 8.8, 95.9 ± 7.4, and 97.9 ± 7.1, respectively. Patellar height and trochlear dysplasia had no influence on redislocation or clinical scores. The Lysholm score was lower in knees with intraoperative retropatellar chondral lesion grade ≥III versus grade

Break Reaction Time after Conservatively Treated Ligament Ruptures of the Ankle.

BACKGROUND: Ankle sprain lesions are the most common ligament lesions in humans. One particularly dangerous consequence of this pathology is an inability to quickly and sufficiently depress the brake pedal when driving a car. The high incidence of the lesion, in the context of a society that is highly automobile-dependent, makes the question "When can a patient safely drive a car again?" of particular socioeconomic importance. HYPOTHESIS/PURPOSE: Though orthopaedic physicians are often confronted with this question, finding an answer in the sparse literature on the topic proves difficult. This study aims to provide a definitive answer to this question. STUDY DESIGN: Prospective Case Control Study. METHODS: 30 patients with grad II and III ligament injuries of the right ankle (18 women, 12 men) and 30 healthy volunteers (19 women, 11 men) participated in this study. Brake reaction time (BRT) was assessed using a previously reported custom-made driving simulator. BRT was assessed two, four and six weeks after injury. Simultaneously the American Orthopedic Foot and Ankle Society Ankle Hindfoot Score (AOFAS-AHS) was assessed. RESULTS: Two weeks after the incident, the patients' BRT measured 690.6±186.2ms. Four weeks after the incident, the BRT improved to 551.8±137.3ms (p<0.001). Compared to the healthy controls' BRT (553.6±118.6ms), there were no significant differences 4 weeks after the injury (p=0.473). At this time, the BRT of both groups was also well below (i.e. faster) than the recommendations of road authorities (700-1500ms). An AOFAS-AHS score of more than 80 points correlated with a sufficient BRT. CONCLUSIONS: Four weeks post injury, patients generally had a sufficient BRT to drive in traffic safely. Some patients could achieve sufficient BRTs at an earlier stage. All patients with sufficient BRTs had an AOFAS-AHS score of ≥81 points. The AOFAS-AHS score can therefore be regarded as an adequate screening tool to evaluate which patients are ready to safely operate motor vehicles earlier.

Prior high tibial osteotomy is not a contraindication for medial unicompartmental knee arthroplasty.

PURPOSE: To report on the outcome and complications of minimal invasive medial unicondylar knee arthroplasty (UKA) after failed prior high tibial osteotomy (HTO) as treatment for medial osteoarthritis in the knee. The hypothesis was that good results can be achieved, if no excessive postoperative valgus alignment and abnormal proximal tibial geometry is present. METHODS: All medial UKAs after failed prior HTO (n = 30), performed between 2010 and 2018 were retrospectively reviewed. The patients were followed for revision surgery and survival of the UKA (defined as revision to TKA). Clinical examination using the Knee Society Score (KSS), Oxford Knee Score (OKS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), as well as radiological examination was performed. Radiographs were studied and the influence of the demographic factors and the radiographic measurements on the survival and the clinical outcome was analysed. RESULTS: After a follow-up of 4.3 ± 2.6 years (2.1-9.9) 27 UKAs were available. The survival rate was 93.0%. Two UKAs were revised to TKA (excessive valgus alignment and tibial loosening with femoropatellar degeneration). Two further patients had revision surgery (hematoma and lateral meniscus tear). Follow-up clinical and radiological examination was performed in 21 cases: KSS 82.9 ± 10.1 (54.0-100.0), KSS (function) 93.3 ± 9.7 (70.0-100.0); OKS 42.7 ± 6.0 (25.0-48.0); WOMAC 7.9 ± 15.6 (0.0-67.1). No significant influence of demographic factors or radiological measurements on the clinical outcome was present. CONCLUSION: Prior HTO is not a contraindication for medial UKA, because good-to-excellent results can be achieved in selected patients with medial osteoarthritis and previous HTO, treated with medial UKA, in a midterm follow-up. Excessive mechanical valgus axis should be avoided; therefore, patient selection and accurate evaluation of medial laxity, preoperative mechanical axis, joint line convergence and proximal tibial geometry are important. LEVEL OF EVIDENCE: III.

Antibiotic therapy alone does not have a high success rate in cases of unexpected positive cultures in intraoperative samples from hip and knee prosthesis revision.

BACKGROUND: Unexpectedly positive bacterial cultures during prosthesis revision surgery still occur on occasion despite good preoperative diagnostics. In such cases a six-week antibiotic therapy without further surgical intervention is recommended. The aim of this study was to find out how successful this procedure is. METHODS: In a study of 508 patients, who required revision surgery of total hip (THA, n = 231) or knee arthroplasties (TKA, n = 277) because of component loosening, biopsy was carried out before their surgery. The collected tissue samples (5) from the biopsy and the revision surgery procedure itself were analyzed according the criteria of the International Consensus Meeting (ICM). Tests revealed 11 patients (7 THA, 4 TKA) with unexpectedly positive bacterial cultures from tissue samples obtained during the revision surgery due to false negative preoperative diagnostic results. These 11 patients were treated with 6 weeks antibiotic therapy and examined with a follow-up of at least 2 years (42.2 ± 16.5 months). RESULTS: Five patients (2 TKA, 3 THA) became reinfected, resulting in a success rate of 54.5%. CONCLUSION: Antibiotic therapy alone of an unexpected positive intraoperative bacterial culture in prosthesis revision surgery seems to be less successful than previously assumed.

The diagnostic value of routine preliminary biopsy in diagnosing late prosthetic joint infection after hip and knee arthroplasty.

AIMS: Biopsy of the periprosthetic tissue is an important diagnostic tool for prosthetic joint infection (PJI) as it enables the detection of the responsible microorganism with its sensitivity to antibiotics. We aimed to investigate how often the bacteria identified in the tissue analysis differed between samples obtained from preoperative biopsy and intraoperative revision surgery in cases of late PJI; and whether there was a therapeutic consequence. METHODS: A total of 508 patients who required revision surgery of total hip arthroplasty (THA) (n = 231) or total knee arthroplasty (TKA) (n = 277) because of component loosening underwent biopsy before revision surgery. The tissue samples collected at biopsy and during revision surgery were analyzed according to the criteria of the Musculoskeletal Infection Society (MSIS). RESULTS: In total, 178 (113 THA, 65 TKA) were classified as infected. The biopsy procedure had a sensitivity of 93.8%, a specificity of 97.3%, a positive predictive value (PPV) of 94.9%, a negative predictive value (NPV) of 96.7%, and an accuracy of 96.1%. Of the 178 infected patients, 26 showed a difference in the detected bacteria from the biopsy and the revision surgery (14.6%). This difference required a change to antibiotic therapy in only two cases (1.1%). CONCLUSION: Biopsy is a useful tool to diagnose PJI, but there may be a difference in the detected bacteria between the biopsy and revision surgery. However, this did not affect the choice of antibiotic therapy in most cases, rendering the clinical relevance of this phenomenon as low. Cite this article: Bone Joint J 2020;102-B(3):329-335.

[Technique of all arthroscopic autologous chondrocyte implantation (ACI) for the treatment of cartilage defects in the knee]. / Technik der vollarthroskopischen autologen Chondrozytentransplantation zur Behandlung von Knorpeldefekten des Kniegelenks.

OBJECTIVE: All arthroscopic treatment of deep cartilage defects in the knee for reconstruction of the articular surface. INDICATIONS: Focal cartilage defects of the knee (ICRS ≥ grade 3) from a size of 2.5 cm2 and more. CONTRAINDICATIONS: Osteoarthritis (Kellgren-Lawrence > grade 2), osseus defect situation, cartilage lesion of the opposing articular surfaces (ICRS > grade 2), instability, malalignment (>3-4°), inflammatory joint diseases. SURGICAL TECHNIQUE: First procedure (cell harvesting): Treatment of additional pathologies, preparation of the cartilage defect, harvesting of osteochondral cylinders for cell culture. Second procedure (cell implantation): Dry arthroscopy, cleaning and drying of the already prepared defect, implantation of the in situ crosslinking cartilage cell suspension. POSTOPERATIVE MANAGEMENT: First procedure (cell harvesting): Early functional treatment with weight bearing as tolerated. Second procedure (cell implantation): No drains, extension brace for 4 days, then free range of motion, partial weight bearing for 4 weeks in patellofemoral implantation and for 8 weeks in tibiofemoral implantation, continuous passive motion beginning in postoperative week 2, cycling from postoperative week 9. RESULTS: In the literature, results for ACI in the knee are reported to be good, especially for larger cartilage defects. Arthroscopic techniques should lead to a decrease of complications and perioperative morbidity. No technique-specific complications occurred in our cohort. From 2012-2015, 98 patients were treated using the above mentioned technique, whereby 62 patients were retrospectively evaluated after 31.0 ± 14.8 (12.5-61.4) months. In 15 patients (28%) additional procedures were performed (7 anterior cruciate ligament reconstructions, 3 correction osteotomies and 5 medial patellofemoral ligament reconstructions). Average cartilage defect size was 4.7 ± 2.8 cm2, in 18 patients (29%) more than one cartilage defect was treated. The subjective IKDC and total KOOS scores resulted in 66 ± 10 and 73 ± 19 points.

Posterior cruciate ligament lesions are mainly present as combined lesions even in sports injuries.

PURPOSE: To analyse 1000 consecutive patients, treated with isolated or combined posterior cruciate ligament (PCL) reconstruction in a single centre according to the epidemiological factors and differences in injury patterns depending on the activity during trauma. METHODS: Between 2004 and 2019, one thousand isolated and combined PCL reconstructions were performed. The medical charts and surgical reports of all patients were analysed regarding epidemiological factors. The PCL lesions were divided into isolated and combined lesions with at least one additional ligamentous injury. The influence of activity during accident and additional injury on the presence of isolated or combined lesions and injury patterns was calculated. RESULTS: In 388 patients (38.8%), sporting activity was the main activity in PCL lesions, followed by traffic accidents in 350 patients (35.0%). Combined injuries were present in 227 patients (58.5%) with sports injuries and 251 patients (71.7%) with traffic accidents. Only during handball, an isolated PCL lesion (69.1%) was more common than a combined lesion. Highest rate of combined lesions was present in car accidents (91.7%). In all activities except skiing and biking, the most common additional peripheral injury was a tear of the posterolateral corner. In skiing and biking accidents, the most common additional peripheral lesion was a lesion of the medial collateral ligament. In patients with PCL lesion and additional fracture of the same lower extremity, a combined lesion was more common than an isolated lesion (p = 0.001). CONCLUSION: Combined PCL lesions are more common than isolated lesions, even in sports injuries (except handball). Incidence and injury pattern vary depending on activity during trauma. Main additional peripheral lesion is a lesion of the posterolateral corner, except biking and skiing accidents where a medial lesion is more common. LEVEL OF EVIDENCE: Level III.

Soaking of the graft in vancomycin dramatically reduces the incidence of postoperative septic arthritis after anterior cruciate ligament reconstruction.

PURPOSE: To determine and compare the incidence of postoperative septic arthritis following anterior cruciate ligament reconstruction (ACLR) with and without soaking of the graft in vancomycin solution prior to implantation in a large single-centre case series. METHODS: From 2004 to 2019, a total of 10,516 primary ACLR were performed and reviewed with regard to the occurrence of postoperative septic arthritis. From February 2017 onwards, all grafts were wrapped in a vancomycin-soaked (5 mg/ml) gauze swab between harvest and implantation (2294 patients, treatment group (2), prospectively followed). These were compared to 8222 patients before that date (control group (1), retrospectively evaluated). The technique of ACLR did not significantly change during the years of the study. There was no difference between the groups with regard to graft choice: Hamstring tendons were used in 99% and quadriceps tendons were used in 1% in both groups, respectively (n.s.). Routine follow-up examination was performed at 6 weeks (follow-up rate 97.1%) postoperatively. Patients with no treatment for septic arthritis at that time were classified as non-infected. RESULTS: There were 35 cases of postoperative septic arthritis in group 1 (incidence: 0.4%), and none in group 2 (incidence 0.0%), respectively. The difference was significant (p < 0.001). CONCLUSIONS: Soaking of the graft in vancomycin solution prior to implantation dramatically reduces the incidence of postoperative septic arthritis in primary ACLR and should, therefore, be used in prevention of this major complication. LEVEL OF EVIDENCE: III.

Lower incidence of post-operative septic arthritis following revision anterior cruciate ligament reconstruction with quadriceps tendon compared to hamstring tendons.

PURPOSE: To determine and compare the incidence of post-operative septic arthritis following revision anterior cruciate ligament reconstruction (R-ACLR) with autologous quadriceps tendon (with patellar bone block) compared to autologous hamstring tendons (semitendinosus and gracilis). METHODS: A total of 1638 isolated R-ACLR with either autologous hamstring tendons (n = 1004, 61.3%) or quadriceps tendon (n = 634; 38.7%) were performed between 2004 and 2017 and were retrospectively analysed with regard to the occurrence of post-operative septic arthritis. The technique of R-ACLR did not significantly change during the years of the study. All patients received pre-op i.v.antibiotics, but no presoaking of the grafts in vancomycin was performed in the years of the study. The individual decision of graft choice was based on graft availability, tunnel position and the presence of tunnel widening. Generally, hamstring tendons were preferred. There were no clinically relevant differences between the groups regarding gender or age. Routine follow-up examination was performed 6 weeks after the index operation (follow-up rate 96.5%), and patients unsuspicious for septic arthritis at that time were classified as non-infected. RESULTS: Fourteen patients with septic arthritis were identified, resulting in an overall incidence of 0.85%. There was one patient with septic arthritis in the quadriceps tendon group (incidence: 0.16%) and 13 patients in the hamstring tendons group (incidence: 1.29%), respectively. The difference was significant (p = 0.013). CONCLUSION: In this series, the incidence of post-operative septic arthritis after R-ACLR was lower when quadriceps tendon graft was used compared to hamstring tendon grafts. LEVEL OF EVIDENCE: III.

C-reactive protein is not a screening tool for late periprosthetic joint infection.

BACKGROUND: Preoperative diagnosis of periprosthetic joint infection (PJI) is important because of the therapeutic consequences. The aim of the present study is to investigate whether the serum C-reactive protein (CRP) level can be used as a screening tool for late PJI. MATERIALS AND METHODS: A cohort of 390 patients with revision surgery of total hip prostheses (200) or total knee prostheses (190) was assessed for late PJI by determining CRP serum level and performing preoperative aspiration with cultivation and intraoperative tissue analyses with cultivation and histologic examination, using the Musculoskeletal Infection Society (MSIS) and International Consensus Meeting (ICM) criteria. RESULTS: A total of 180 joints were rated as PJI (prevalence 46%). Of these, 42.8% (77) showed a CRP level below 10 mg/L and 28.3% (51) showed a normal CRP level of less than 5 mg/L. The 76.9% of the cases with slow-growing bacteria showed a CRP level below 10 mg/L, and 61.5% showed a normal CRP level. CONCLUSIONS: Serum CRP level should not be used as a screening tool to rule out late PJI. LEVEL OF EVIDENCE: Level 2 (diagnostic study).

Midterm Results after Implant-Free Patellar Fixation Technique for Medial Patellofemoral Ligament Reconstruction.

Problems and complications concerning the patellar fixation in medial patellofemoral ligament reconstruction (MPFLR) have been reported. The purpose of this retrospective study was to systematically analyze the surgical technique for MPFLR with a V: -shaped patellar bonetunnel for implant-free fixation of an autologous gracilis tendon, allowing early functional rehabilitation, regarding restoration of the patellofemoral stability, patient satisfaction, return to sports, and technique-specific complications. In 2010, 128 cases of consecutive isolated MPFLR were performed. All these cases were included. After a minimum follow-up of 3 years, 104 cases were retrospectively analyzed (follow-up: 81.3%) with regard to redislocation, subjective functional outcome (Tegner's score and sports level compared with preoperative level), patient satisfaction, revision surgery, and technique-specific complications. After a follow-up of 45.7 ± 3.2 months, 101 of 104 cases (97.1%) showed no redislocation. Mean Tegner's score was 5.1 ± 1.8 (range, 2-9). A total of 61.5% patients reported about a higher sports level compared with their preoperative level. The patient satisfaction was high with 94.2%. In two cases (1.9%), technique-specific problems occurred as the bone bridge of the V: -shaped tunnel was insufficient due to a malpositioning of the aiming device. No further technique-specific problems occurred and no revision surgery was necessary during the observational period. The presented surgical technique is safe and it reliably restores the patellofemoral stability, with a low rate of redislocations, an excellent subjective functional outcome, and a high-patient-reported satisfaction. No major technique-specific complications occurred.

Derotational femoral osteotomy changes patella tilt, patella engagement and tibial tuberosity trochlear groove distance.

PURPOSE: The aim was to assess the influence of femoral derotational osteotomy on patella tilt (PT), axial patella engagement (AEI) and tibial tuberosity trochlear groove distance (TTTG). METHODS: Derotational femoral osteotomy was performed on ten lower limbs of body donors embalmed with alcohol-glycerine. Femoral torsion, tibial torsion, knee torsion, PT, AEI and TTTG were evaluated on axial CT slices for an absolute femoral torsion of 15°, 20°, 25°, 30°, 35° and 40°. A linear mixed model analysis was used to estimate the effect of femoral torsion on PT, AEI, TTTG and knee torsion adjusted for correlation due to repeated observations. Estimates with 95% confidence intervals were used to represent the mean change in the dependent variables for one unit of change (degree, mm or AEI) in the predictor variable. RESULTS: A significant correlation was observed between femoral torsion and AEI (p < 0.001), PT (p < 0.001) and TTTG distance (p = 0.002). In cases of increased internal femoral torsion, a significant decreased AEI (estimate - 0.003, 95% CI - 0.003 to - 0.002), an increased PT (estimate 0.3, 95% CI 0.2-0.4) and an increased TTTG distance (estimate 0.1, 95% CI 0.1-0.2) were observed. No correlation was seen between change in femoral torsion and knee torsion (n.s.). CONCLUSIONS: Derotational femoral osteotomy has a significant impact on patella tilt and axial patella engagement. Moreover, TTTG distance is slightly changed by a derotational femoral osteotomy, which has to be taken into account preoperatively when considering surgical procedures. LEVEL OF EVIDENCE: Level V.

Excellent long-term results in combined high tibial osteotomy, anterior cruciate ligament reconstruction and chondral resurfacing in patients with severe osteoarthritis and varus alignment.

PURPOSE: To determine survivorship and functional results of medial open-wedge high tibial osteotomy (HTO) combined with anterior cruciate ligament reconstruction (ACLR) and a chondral resurfacing (CR) procedure (abrasion/microfracture) in patients with Kellgren-Lawrence grade 3 and 4 osteoarthritis with full thickness-cartilage defects, ACL-insufficiency and varus alignment. METHODS: A cohort of 23 patients undergoing a combined procedure of HTO (fixation with angular stable internal fixator, Tomofix®), ACLR and CR for the treatment of severe symptomatic medial osteoarthritis, ACL insufficiency and varus alignment (> 4°) between 2005 and 2009 was prospectively surveyed with a minimum follow-up of 10 years with regard to survival (not requiring arthroplasty), functional outcome (subjective IKDC score), pain level (numeric rating scale), Oxford Knee Score (OKS) and subjective satisfaction. The Wilcoxon signed-rank-test was used for statistical evaluation of non-parametric data in these related samples. RESULTS: Twenty-one cases were included, one case with incomplete follow-up data and another case excluded. The follow-up rate was 91% at 12.0 ± 1.0 years (10.0-13.4). Mean age at time of surgery was 47.3 ± 5.9 years (37.8-57.7). At final follow-up, no arthroplasty was performed in any of the cases (survival: 100%). Subjective IKDC score improved from 47 ± 11 to 75 ± 15 at 1, 72 ± 15 at 3, 73 ± 17 at 6 years and 70 ± 16 at final follow-up (p < 0.001), respectively. At final follow-up the OKS was 40 ± 7 (17-48) and pain-level significantly decreased from 7.5 ± 1.0 preoperatively to 2.9 ± 2.3 (p < 0.001) at final follow-up. All patients were satisfied with the result and stated that they would retrospectively undergo the procedure again. CONCLUSION: A combined approach of HTO, ACLR and a CR shows excellent results in a long-term follow-up in selected young patients even in severe osteoarthritis. However, the role and potential benefit of the ACLR and CR compared to HTO alone remains unclear. LEVEL OF EVIDENCE: Therapeutic case series, Level IV.

Soaking of autografts in vancomycin is highly effective in preventing postoperative septic arthritis after revision anterior cruciate ligament reconstruction.

PURPOSE: To determine and compare the incidence of postoperative septic arthritis following revision anterior cruciate ligament reconstruction (R-ACLR) with and without soaking of the graft in vancomycin solution prior to implantation in a large single-centre series. METHODS: A total of 2155 isolated R-ACLR with autologous tendons were performed from 2004 to 2019 and were reviewed with regard to the occurrence of postoperative septic arthritis. From February 2017 onwards, all grafts were wrapped in a vancomycin-soaked (5 mg/ml) gauze swab between harvest and implantation (517 patients, treatment group (2), prospectively followed). These were compared to 1638 patients before that date (control group (1), retrospectively evaluated). The technique of R-ACLR did not significantly change during the years of the study. Hamstring tendons were used in 1310 patients (60.8%) and quadriceps tendons with patellar bone block were used in 845 patients (39.2%), respectively, with no difference between the groups (n.s.). Routine follow-up examination was performed 6 weeks postoperatively (follow-up rate 96.5%), and patients with no treatment for septic arthritis until that time were classified as non-infected. RESULTS: There were 14 cases of postoperative septic arthritis in group 1 (incidence 0.9%), and none in group 2 (incidence 0.0%), respectively. The difference was significant (p = 0.029). CONCLUSION: Soaking of the graft in vancomycin solution prior to implantation dramatically reduces the incidence of postoperative septic arthritis in R-ACLR. LEVEL OF EVIDENCE: III.

Arthroscopic autologous chondrocyte implantation in the knee with an in situ crosslinking matrix: minimum 4-year clinical results of 15 cases and 1 histological evaluation.

PURPOSE: To clinically evaluate an arthroscopic autologous chondrocyte implantation (ACI) technique with an in situ crosslinking matrix for the treatment of full thickness cartilage defects of the knee and to present histological results of a graft cartilage biopsy obtained after 1.5 years. METHODS: Fifteen cases of arthroscopic autologous chondrocyte implantation in the knee performed between November 2011 and October 2012 were included in the study. Medical charts and operational reports were screened and the patients were contacted after 0.8 ± 0.3 years (0.4-1.3) and 4.3 ± 0.3 years (4.0-4.8) to asses subjective IKDC and re-operation. The Tegner activity scale was collected at the second follow-up time point. Subjective IKDC response rates were assessed at both follow-up time points. RESULTS: The first and second follow-up was completed by all 15 patients (100%). The subjective IKDC scores showed a significant improvement (pre-operative 44.5 ± 15.9, first follow-up 71.1 ± 15.9, p < 0.001, second follow-up 72.6 ± 17.3, p < 0.001). The overall response rate was 66.7% (n = 10) at follow-up one and two. There were no significant differences in pre-injury (4, range 1-9) and follow-up two (4, range 2-7) Tegner activity scales (p = n.s.). Two patients required re-operation in the index knee, not related to the ACI procedure. No complication related to the ACI or the implantation technique occurred. The histological results showed excellent cartilage regeneration. CONCLUSION: Arthroscopic ACI using an in situ crosslinking matrix is a safe and reliable treatment option for full-thickness cartilage defects of the knee.