Patella component diameters of 38 mm and up might be associated with higher revision rates after patella resurfacing.

PURPOSE: Patellar resurfacing is considered the standard of care for total knee arthroplasty in the USA. Complications of patella resurfacing include aseptic loosening or patella fractures and can threaten the integrity of the extensor mechanism. The goal of this study was to report on patella button revision rates in posterior stabilized total knee arthroplasty. MATERIAL AND METHODS: Between 01/2010 and 08/2016 patella buttons were implanted in 1056 patients (267 men and 550 women) as part of a posterior stabilized total knee arthroplasty. RESULTS: Of 1056 cases, 35 cases (14 women, 15 men, 5 bilateral, 3.3%) showed early loosening at a mean 52.5 months postoperatively. Patella components of 38 mm or larger diameters showed a significantly higher loosening rate than the 29, 32, 35 mm buttons (p < 0.01). Mean BMI of patients identified with aseptic loosening was 31.7 kg/m2, mean age at time of revision surgery was 63.3 years. All of the patients with loosening of the patella button required revision surgery; in 33 cases an exchange of the button was performed, in two cases a removal of the button and patellar bone grafting was indicated. No complications occurred after revision surgery. CONCLUSION: The current study reports a 3.3% patella loosening rate during this mid-term follow-up. Size 38 mm and larger patella components showed a significantly higher revision rate than smaller buttons and the authors advise caution when using large diameter patella components.

The periacetabular osteotomy: angulation of the supraacetabular osteotomy for quantification of correction.

BACKGROUND: Malcorrection of the acetabular fragment in periacetabular osteotomy (PAO) is associated with inferior outcomes. 2-dimensional radiographic parameters are being used for intraoperative verification of a satisfactory result. After reorientation of the fragment, the acetabular version must be verified with an intraoperative radiograph. In the case of an unsatisfactory correction, a reorientation would be required. A slim and radiation-free intraoperative navigation method to directly quantify the correction is highly desirable. AIM: To find out whether the measurable angulation of the supraacetabular osteotomy can be used for this purpose. METHODS: To determine the angulation, 13 consecutive patients who underwent a PAO were investigated. The preoperative and postoperative standard radiographs as well as CT scans were available. The surgically produced alteration of radiographic parameters was correlated to tilting and spreading of the supraacetabular osteotomy planes. RESULTS: Tilting of the supraacetabular osteotomy planes correlates strongly to alteration of the lateral centre-edge angle (LCEA) and the acetabular index (ACI), whereas spreading of the same planes showed also a strong correlation, but to the LCEA only. 1° of tilting resulted in a 0.2° alteration of the LCEA and a 0.5° alteration of the ACI, whereas 1° of spreading resulted in a 0.5° alteration of the LCEA. CONCLUSIONS: This study shows that the measurable angulation of the supraacetabular osteotomy planes can be used to monitor the three-dimensional reorientation of the acetabular fragment in PAO. As long as sophisticated modalities are lacking, this technique offers an easy way to intraoperatively navigate the correction in PAO.

Do cobalt and chromium blood metal ion levels normalize after revision of failed metal-on-metal total hip replacements?

INTRODUCTION: Increased cobalt (Co) and chromium (Cr) serum levels are one reason for revision surgery in metal on metal (MoM) total hip arthroplasty (THA) patients. Dual mobility liners are a simple revision option; however, they preserve the metal shell and stem and it is therefore not clear if metal ion levels will fully normalize after revision surgery. MATERIAL AND METHODS: Between April 2013 and December 2017 25 hips (24 patients) underwent revision from a MoM THA to an off-label dual mobility liner. Five patients were lost to follow-up and one patient refused leaving 18 patients (11 men, 7 female, average age 63.9 years) for pre- and postoperative metal ion level blood tests at a minimum follow-up of 2 years. RESULTS: Fourteen patients were revised for osteolysis, two for elevated metal ion levels and two for fluid or cysts around the femoral or acetabular component. The average preoperative Co and Cr levels were 8.3 µg/l and 5.0 µg/l, respectively. At a minimum follow-up of 2 years (30-95 months), metal ions dropped to 0.8 µg/l. Harris Hip Score (HHS), Hip Osteoarthritis Outcome Score (HOOS), Visual Analog Scale (VAS) and the UCLA activity score improved non-significantly from pre- to postoperative. There was one postoperative complication in the study cohort. One patient with persisting pain required revision surgery to a standard acetabular component during the follow-up period. CONCLUSION: The off-label use of a dual-mobility liner in the current study resulted in normalization of the metal ion levels suggesting that preserving the cobalt-chromium acetabular component has little impact on ion levels. In addition, dual mobility liners have a low complication and revision rate.

History of COVID-19 infection is not associated with increased D-dimer levels and risk of deep-vein thrombosis in total joint arthroplasty.

INTRODUCTION: In the acute phase of COVID-19, elevated D-dimer levels indicate a hypercoagulable state putting the patients at increased risk for venous thromboembolic disease (VTE). It is unclear, if prior COVID-19 disease increases the risk for VTE after total joint arthroplasty (TJA) and if D-dimer levels can be used to identify patients at risk. MATERIALS AND METHODS: D-Dimer levels of 313 consecutive SARS-CoV-2 IgG-positive and 2,053 -negative patients undergoing TJA between 05/20 and 12/20 were evaluated. D-Dimer levels were divided into three groups: < 200 ng/ml, 200-400 ng/ml, and > 400 ng/ml D-dimer units (DDU). 277 SARS-CoV-2 IgG-positive patients underwent a Doppler ultrasound to rule out deep-vein thrombosis (DVT) 4-6 weeks after TJA. RESULTS: D-Dimer levels did not differ significantly between SARS-CoV-2 IgG-positive and -negative patients (p value 0.53). Among SARS-CoV-2 IgG-negative patients, 1687 (82.17%) had D-dimer levels < 200 ng/ml, 256 (12.47%) between 200 and 400 ng/ml, and 110 (5.36%) > 400 ng/ml. Of the SARS-CoV-2 IgG-positive patients, 257 (83.71%) had D-dimer levels < 200 ng/ml, 34 (11.07%) between 200 and 400 ng/ml, and 16 (5.21%) > 400 ng/ml. A postoperative DVT was detected in nine patients (2.9%) in the SARS-CoV-2 IgG-positive group and a PE in one patient (0.3%). 7/229 patients with < 200 ng/ml (3.1%), 1/28 patients (3.6%) with 200-400 ng/ml and 1/9 patients (11.1%) with D-dimer levels > 400 ng/ml had a DVT or PE (p = 0.43). CONCLUSIONS: The findings of this investigation suggest there is no difference in D-dimer levels between SARS-CoV-2 IgG-positive and -negative patients undergoing TJA. Although there is a trend for increased VTE rates with increased D-dimer levels, routine D-dimer testing is not recommended based on the current data. SARS-CoV-2 IgG-positive patients have a low risk of VTE in the current study.

Blood management in direct anterior versus posterior primary total hip arthroplasty using tranexamic acid: a matched cohort study.

INTRODUCTION: Proponents of the direct anterior approach (DAA) for THA claim patients recover faster compared to primary THA through the posterior approach (PA). Blood loss and transfusion have substantially declined with the use of tranexamic acid (TXA). However, it is still controversial if hemoglobin drops and transfusion rates are affected by the surgical approach when TXA is routinely used. MATERIALS AND METHODS: 2418 patients undergoing DAA THA were matched 1:1 with patients undergoing PA THA according to preoperative hemoglobin (± 1 g/dl), age (± 5 years), sex, BMI (± 5 kg/m2) and year of surgery (± 2 years). All patients received perioperative TXA. None of the patients donated autologous blood. Hemoglobin levels, drain placement and output, blood transfusion rates and volume as well as length of stay were recorded. RESULTS: A closed suction drain was used in 121 (5.0%) DAA and in 135 (5.6%) PA THAs (p = 0.369). Mean drain output was higher in the DAA compared to the PA group (134 ml (0-520 ml) versus 92.3 ml (0-600 ml), p = 0.004). There was no difference in hemoglobin drop [2.6 g/dl versus 2.6 g/dl (p = 0.143)] and transfusion rate [n = 31 (1.3%) versus n = 29 (1.2%), p = 0.793)] between DAA and PA THA. Mean transfusion amounts were 421.8 ml (250-1120.8 ml) in the DAA and 353.9 ml (250-560 ml) in the PA group (p = 0.801). The length of stay was shorter in the DAA group with a mean 1.6 days versus 2.1 days in the PA group (p ≤ 0.001). CONCLUSION: In this large matched cohort study, there was no difference in the perioperative hemoglobin drop, the transfusion rate and the transfusion amount between DAA and PA THA.

Preoperative ferritin and hemoglobin levels are lower in patients with a history of COVID-19 but blood loss and transfusion requirements are not increased.

INTRODUCTION: A history of COVID-19 (Coronavirus Disease 2019), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may have an impact on hemoglobin and ferritin levels predisposing patients to increased blood transfusion requirements following total joint arthroplasty (TJA). The current study compares ferritin levels, hemoglobin levels, and transfusion rates between SARS-CoV-2 IgG positive and SARS-CoV-2 IgG negative TJA patients. MATERIALS AND METHODS: Preoperative ferritin levels, pre- and postoperative hemoglobin levels, postoperative change in hemoglobin, and transfusion rates of 385 consecutive SARS-CoV-2 IgG positive patients undergoing TJA were compared to those of 5156 consecutive SARS-CoV-2 IgG negative patients undergoing TJA. RESULTS: Preoperative hemoglobin levels were significantly lower in SARS-CoV-2 IgG positive patients [13.3 g/dL (range 8.9-17.7 g/dL)] compared to 13.5 g/dl (7.3-18.3 g/dL; p value 0.03). Ferritin levels were significantly lower in SARS-CoV-2 IgG positive patients (mean of 106.1 ng/ml (2.1-871.3.3 ng/ml) vs. 123.7 ng/ml (1.4-1985 ng/ml) (p value 0.02)). Hemoglobin on postoperative day (POD) one, after four-six weeks, and transfusion rates did not differ between the two groups. CONCLUSION: Although preoperative hemoglobin and ferritin levels are lower in SARS-CoV2 IgG positive patients, there was no difference in hemoglobin on POD one, recovery of hemoglobin levels at four-six weeks postoperatively, and transfusion rates after surgery. Routine ferritin testing prior to TJA is not recommended in SARS-CoV-2 IgG positive patients.

The impact of the COVID-19 associated shutdown on orthopedic patient care.

BACKGROUND: Due to the surge of COVID-19 cases in the US in early March 2020, health care facilities temporarily suspended elective and non-urgent medical procedures such as joint replacement surgeries. The aim of this study was to analyze the impact of the COVID-19 associated shutdown on orthopedic patient care at a specialized orthopedic hospital located at the epicenter of the COVID-19 pandemic. METHODS: Patient volume of outpatient visits and joint replacement surgeries were analyzed and compared for 2019 and 2020. The volumes were further aligned with the timeline of governmental and institutional COVID-19 associated restrictions. RESULTS: The annual surgery volume was reduced by 20.2% in 2020 and did not make up for the reduction experienced during the shutdown. The total number of patient visits decreased by 25.5% and new patient visits remained 25% lower at the end of 2020. Patient care and surgery volume recovered with declining SARS-CoV-2-cases but did not return to levels prior to the shutdown. During the second quarter of 2020, 28.5% of all patient visits were telehealth appointments. By the end of the year it dropped to 7.6%. There was a shift towards patient appointments at outpatient satellite offices. CONCLUSION: Orthopedic providers faced a substantial disruption in outpatient and surgical volume. Telemedicine appointments were crucial for maintaining follow-up patient care and will be an important sector in future patient care. There has been a major push to utilize satellite offices outside the city center.

Erratum to 'Impaction Bone Grafting in Revision Total Knee Arthroplasty-Using Mesh and Cone to Contain the Defect: A Report of 3 Cases' [Arthroplasty Today 6 (2020) 578-584].

[This corrects the article DOI: 10.1016/j.artd.2020.07.001.].

Hip resurfacing and posterior approach total hip arthroplasty have equivalent blood loss when tranexamic acid is used: a propensity score matched cohort analysis.

INTRODUCTION: Hip resurfacing (HR) requires a larger approach and soft tissue dissection and might therefore be associated with increased blood loss compared to total hip arthroplasty (THA). However, the effect of the adoption of tranexamic acid (TXA) in this setting is unknown. Therefore, the current study compares the blood loss and transfusion requirements between HR and posterior THA in patients receiving TXA. MATERIALS AND METHODS: This retrospective cohort study included patients undergoing primary, unilateral THA or HR using a posterior approach between February 2016 and 2020 in which TXA was administered. THA and HR patients were propensity score matched using nearest neighbor greedy matching accounting for demographic, health and surgical variables. Postoperative hemoglobin (Hgb) levels and Hgb drop from preoperative to post-operative day (POD) 1 were compared using t-tests and associated risk factors were assessed using linear mixed modelling. RESULTS: After matching, each cohort consisted of 1395 patients. Cohorts were similar regarding age, sex, BMI, and Charlson Comorbidity Index. No significant differences were found for Hgb levels on POD 1 (12.3 g/dl; p = 0.90) or Hgb drop (2.3 g/dl; p = 0.87). Duration of surgery was significantly longer for HR patients (82 vs 77 min; p < 0.01). Transfusion rate was 0.1% in both cohorts (p = 1.00). Hospital stay was significantly shorter for HR patients (1 vs 2 days; p < 0.01). CONCLUSION: HR using a standard TXA regimen is not associated with greater perioperative blood loss than posterior THA and does not result in increased transfusion requirements. Both surgical procedures can be considered equally safe in terms of perioperative blood management when TXA is used.

A standardized soft tissue release technique to lower the risk of greater trochanteric fractures for the anterior approach in total hip arthroplasty.

INTRODUCTION: The direct anterior approach (DAA) is suggested to accelerate postoperative recovery and decrease the dislocation risk after primary total hip arthroplasty (THA). However, exposure of the femur can be challenging. Insufficient exposure increases the risk for intraoperative femoral fracture. MATERIALS AND METHODS: Of 435 consecutive anterior THA, the first 102 consecutive THA in 94 patients were treated with an external rotator tendon "release-on-demand" (RoD). The following 311 consecutive patients (333 THA) underwent routine release of the conjoint tendon (CTR) of its bony insertion on the greater trochanter only. Retrospective analysis recorded trochanteric fractures, intraoperative calcar fractures, postoperative periprosthetic fractures, stem subsidence, ossifications, and dislocations. RESULTS: Three (2.9%) fractures of the greater trochanter were recorded in the RoD group, but no (0.0%) fractures occurred in the CTR group (p = 0.002). There was no significant difference in the occurrence of intraoperative calcar fractures (0% (RoD) vs. 1.2% (CTR), p = 0.267), postoperative periprosthetic fractures (0% (RoD) vs. 0.3% (CTR), p = 0.560), stem subsidence (2.0% (RoD) vs. 1.2% (CTR), p = 0.565) or ossifications (2.9% (RoD) vs. 1.6% (CTR), p = 0.344) between these groups. There were no dislocations within a minimum 12 months follow-up period. CONCLUSION: The routine release of the conjoined tendon (CTR group) decreases the shear forces on the tip of the greater trochanter during DAA THA and eliminates the risk of greater trochanter fractures. The routine release of the conjoined tendon did not increase the risk of postoperative dislocations.

Anterior hip replacement: lower dislocation rates despite less restrictions?

INTRODUCTION: Dislocation in Total hip arthroplasty (THA) is a common postoperative complication and reason for revision surgery. The direct anterior approach has become more popular over the last decade. The purpose of this study was to compare postoperative dislocation rates of the direct anterior and the posterior approach at a one-year follow-up. MATERIAL AND METHODS: 797 consecutive hips operated through a posterior approach [698 patients (307 male, 391 female)] between 2009 and 2012, were compared to 690 selected THA [610 patients (423 female, 187 male)] operated since 2012. Anterior hip replacement surgery was primarily indicated for patients demanding increased flexibility after surgery (Yoga) or were considered a higher risk for dislocation. RESULTS: During a one-year follow-up there were eight dislocations out of 797 THA (1%) in the posterior group and none in the 690 THA (0%) in the anterior group (p-value of 0.008). Average time to dislocation was 7.5 weeks in the posterior group. Five of eight patients with dislocations needed revision surgery due to persistent instability. CONCLUSION: Even in a higher-risk patient population, the direct anterior approach showed a lower dislocation rate compared to the posterior approach in the first year after surgery.

History of COVID-19 Was Not Associated With Length of Stay or In-Hospital Complications After Elective Lower Extremity Joint Replacement.

BACKGROUND: The impact of previous SARS-CoV-2 infection on the morbidity of elective total joint arthroplasty (TJA) is not fully understood. This study reports on the association between previous COVID-19 disease, hospital length of stay (LOS), and in-hospital complications after elective primary TJA. METHODS: Demographics, comorbidities, LOS, and in-hospital complications of consecutive 340 patients with a history of COVID-19 were compared with those of 5014 patients without a history of COVID-19 undergoing TJA. History of COVID-19 was defined as a positive IgG antibody test for SARS-CoV-2 before surgery. All patients were given both antibody and polymerase chain reaction tests before surgery. RESULTS: Patients with a history of COVID-19 were more likely to be obese (43.8% vs 32.4%, P < .001), Black (15.6% vs 6.8%, P < .001), or Hispanic (8.5% vs 5.4%, P = .028) than patients without a history of COVID-19. COVID-19 treatment was reported by 6.8% of patients with a history of COVID-19. Patients with a history of COVID-19 did not have a significantly longer median LOS after controlling for other factors (for hip replacements, median 2.9 h longer, 95% confidence interval = -2.0 to 7.8, P = .240; for knee replacements, median 4.1 h longer, 95% confidence interval = -2.4 to 10.5, P = .214), but a higher percentage were discharged to a post-acute care facility (4.7% vs 1.9%, P = .001). There was no significant difference in in-hospital complication rates between the 2 groups (0/340 = 0.0% vs 22/5014 = 0.44%, P = .221). CONCLUSIONS: We do not find differences in LOS or in-hospital complications between the 2 groups. However, more work is needed to confirm these findings, particularly for patients with a history of more severe COVID-19. LEVEL OF EVIDENCE: II.

D-Dimer Levels Are Not Elevated in SARS-CoV-2 IgG Positive Patients Undergoing Elective Orthopedic Surgery.

INTRODUCTION: In acute COVID-19, D-Dimer levels can be elevated and those patients are at risk for thromboembolic events. This study aims to investigate differences in preoperative D-Dimer levels in SARS-CoV-2 IgG positive and negative patients undergoing primary total knee and total hip replacement (TJA) or spine surgery. METHODS: D-Dimer levels of 48 SARS-CoV-2 IgG positive and 718 SARS-CoV-2 IgG negative spine surgery patients were compared to those of 249 SARS-CoV-2 IgG positive and 2102 SARS-CoV-2 IgG negative TJA patients. Patients were assigned into groups based on D-Dimer levels as follows: <200 ng/mL, 200-400 ng/mL, and >400 ng/mL D-Dimer Units (DDU). RESULTS: D-Dimer levels did neither differ significantly between SARS-CoV-2 IgG positive spine surgery patients and TJA patients (p = 0.1), nor between SARS-CoV-2 IgG negative spine surgery and TJA patients (p = 0.7). In addition, there was no difference between SARS-CoV-2 IgG positive and negative spine surgery patients and SARS-CoV-2 IgG positive and negative TJA patients (p = 0.3). CONCLUSIONS: There is no difference in D-Dimer levels between SARS-CoV-2 IgG positive and negative patients and there does not seem to be any difference for different orthopedic specialty patients. Routine testing of D-Dimer levels is not recommended for patients undergoing elective orthopedic surgery.

Restoring range of motion in reduced acetabular version by increasing femoral antetorsion - What about joint load?

BACKGROUND: Acetabular retroversion results in reduced range of motion, and is thought to contribute to femoroacetabular impingement. Severe retroversion can be corrected with a periacetabular osteotomy, which is a technically demanding intervention. In this study, we investigated whether increasing femoral antetorsion is a potential alternative to restore the range of motion and how this approach would affect hip joint loading. METHODS: Six different finite element models of the same subject were built from MRI and used to simulate different load scenarios during stance phase, including healthy and pathological configurations with different acetabular version and femoral torsion angles. The subject's gait was analysed in our gait lab and motion data as well as joint reaction forces were integrated into the model. Hip range of motion, hip abductor muscle forces as well as localization and magnitude of hip joint loads were determined. FINDINGS: The negative effects of acetabular retroversion on hip range of motion including flexion and internal rotation can be reversed by increasing femoral anteversion. The rotation of the femur furthermore affected muscular functionality by shortening the moment arms of the hip abductor muscles, resulting in increased abductor muscle forces, joint reaction forces and hip joint loading. INTERPRETATION: Even though increased femoral antetorsion can compensate for the loss of hip range of motion due to reduced acetabular version, rotational ostotomy of the proximal femur is likely to alter muscular moment arms and therefore increase hip joint load, conflicting the goal of a long-term healthy joint.

Flexor hallucis longus hypertrophy secondary to Achilles tendon tendinopathy: an MRI-based case-control study.

PURPOSE: The purpose of this study was to outline an indirect sign of advanced Achilles tendinopathy on magnetic resonance imaging (MRI), based on the hypothesis that these patients would present with secondary hypertrophy of the flexor hallucis longus muscle (FHL). METHODS: MRI scans of Achilles tendon were analyzed retrospectively in two cohorts. The study group consisted of consecutive patients presenting with clinical signs of Achilles tendinopathy and no previous surgeries, while the control group were patients that had an MRI due to other reasons and no signs of tendinopathy. Two parameters from two muscle bellies were measured and compared on axial MRI scans 4-5 cm above the ankle joint line at the level of greatest thickness: area and diameter of the triceps surae (TS) and of the FHL muscle. Ratios (FHL/TS) were calculated for area (Ar) and diameter (Dm) measurements. Interobserver agreement was analyzed. A receiver operating characteristic (ROC) curve was created for both ratios to assess potential cutoff points to differentiate between the groups. RESULTS: A total of 60 patients for each study group were included. Both ratios Ar(FHL/TS) and Dm(FHL/TS) showed significant higher values in the tendinopathy group (p < 0.001). There were strong to very strong intraclass correlation coefficients (ICC = 0.75-0.93). A diameter ratio Dm (FHL/TS) of 2.0 or higher had a sensitivity of 49% and specificity of 90% for concomitant Achilles tendinopathy. CONCLUSION: In our patient cohort, FHL hypertrophy was observed in patients with Achilles tendinopathy as a possible compensatory mechanism. Measuring a diameter ratio Dm(FHL/TS) of 2.0 or higher on an axial MRI, may be indicative as an indirect sign of functional deterioration of the Achilles tendon.

Severity of valgus knee osteoarthritis has no effect on clinical outcomes after total knee arthroplasty.

INTRODUCTION: Advanced valgus osteoarthritis (OA) is one of the most challenging indications for total knee arthroplasty (TKA). There is no information in the literature about the optimal timing of surgery. The current study investigates the impact of the preoperative deformity and degree of arthritis on postoperative outcome after TKA. MATERIAL AND METHODS: The study evaluated 133 knees in 107 patients with valgus OA that failed nonoperative treatment with a minimum 2-year follow-up. Mechanical alignment, Kellgren and Lawrence (K/L) score, and minimal joint space width (minJSW) were measured on AP- and hip-to-ankle radiographs. All knees had advanced OA (i.e., K/L grades 3 or 4 and less than 50% minJSW). Pre- and postoperative WOMAC, VR-12, UCLA, VAS, ROM were recorded. RESULTS: There was no difference in clinical outcome (WOMAC, UCLA, VR-12, VAS or ROM) between patients with different degrees of valgus deformities (< 5.0 deg., 5.0-9.9 deg., 10.0-14.9 deg., ≥ 15.0 deg.). There was also no correlation between K/L score or minimal joint space width and any of the outcome parameters. CONCLUSIONS: The degree of valgus deformity and the grade of osteoarthritis do not predict the outcome of TKA in patients with valgus OA. Since the risk of complication and the need for implant constraint increases with increasing deformity and instability of the knee, surgery appears to be justified in patients with advanced OA that failed nonoperative treatment, regardless of the degree of deformity.

The Functional Status of the ACL in Varus OA of the Knee: The Association With Varus Deformity and Coronal Tibiofemoral Subluxation.

BACKGROUND: The present article analyzes the association of the functional anterior cruciate ligament (ACL) status and the overall varus deformity and coronal tibiofemoral subluxation (CTFS) in varus OA of the knee. METHODS: One hundred consecutive knees with varus OA in 84 patients were prospectively included. Knees were divided into two groups, in accordance with the ACL status (functionally sufficient or insufficient). All included patients were potential candidates for unicompartmental knee arthroplasty with predominantly medial compartment OA. Knees with Kellgren/Lawrence ≥ grade 3 in the lateral compartment were excluded leaving 79 knees to be included in this study. Mechanical varus deformity and CTFS were evaluated on AP radiographs and valgus stress radiographs, and compared between the two groups. RESULTS: Knees with a functionally insufficient ACL had significantly more varus deformity on hip-to-ankle AP standing radiographs (P = .001) and on valgus stress radiographs (P = .017). CTFS on AP standing radiographs was significantly higher (P = .045) in knees with a functionally insufficient ACL. Seventy-three percent (8/11) of the ACL-insufficient knees had a varus deformity of ≥10° and 64% (7/11) of ACL-insufficient knees had CTFS ≥ 6mm. By contrast, only one patient (2%, 1/41) with an insufficient ACL had< 10° varus deformity and a CTFS of < 6mm. CONCLUSION: Functional ACL insufficiency in osteoarthritic varus knees is associated with greater varus deformity and more advanced CTFS. Seventy-three percent of ACL-insufficient knees had a varus deformity of ≥10° and 64% of ACL-insufficient knees a CTFS of ≥ 6mm. In the work-up for medial unicompartmental knee arthroplasty, functional ACL insufficiency is likely in knees with varus deformity of ≥10° and CTFS of ≥ 6mm.

Mid-term results after in situ pinning and hip arthroscopy for mild slipped capital femoral epiphysis: a minimum five-year follow-up.

PURPOSE: In situ pinning of mild slipped capital femoral epiphysis (SCFE) results in an aspherical head-neck junction and arthroscopic osteochondroplasty can successfully correct the head-neck junction. However, whether the correction stays stable over at least five years remains unknown. METHODS: In a retrospective and consecutive series, 11 patients with a mean age of 12 years (range, 10 years to 15 years) were included. All patients were treated for mild SCFE with in situ pinning and staged hip arthroscopy correcting the head-neck junction. All patients were assessed clinically and radiographically (radiograph and magnetic resonance imaging (MRI)) pre-operatively, 12 weeks and at least five years' post-operatively. RESULTS: The mean range of motion (ROM) for flexion and internal rotation was stable over time with 100° (sd 4) and 21° (sd 6), respectively at the last follow-up. The mean alpha angle decreased from pre-operative 64° (range 61° to 68°) to 12 weeks post-operative 49° (range 46° to 52°; p = 0.001) and stayed stable over time. New superficial cartilage damage on either the acetabular or femoral side was seen in each three patients. Progressive labral degeneration was present in two patients. CONCLUSION: In situ pinning and staged hip arthroscopy for the correction of mild SCFE is safe, restores normal alpha angles and reveals stable morphological correction at mid-term follow-up. Furthermore, the clinical results were excellent with almost normalized internal hip rotation at mid-term follow-up in patients who had reached adulthood. However, there was some joint deterioration, but without negative impact on subjective and clinical outcome after at least five years. LEVEL OF EVIDENCE: IV.

Impaction Bone Grafting in Revision Total Knee Arthroplasty-Using Mesh and Cone to Contain the Defect: A Report of 3 Cases.

Uncontained tibial bone defects are a challenge in revision total knee arthroplasty. The present study reports on the results of a modified surgical technique for impaction bone grafting using metaphyseal cones and wire mesh. Three patients (2 male, 1 female; average age: 71.3 years) underwent revision total knee arthroplasty. All patients presented with uncontained medial tibial bone defects, one of the patients with an additional posterior cortical tibial split fracture. All cases were treated with a metaphyseal cone and outside mesh to create a contained defect. Between the mesh and cone, fresh frozen cancellous chips mixed with ß-tricalcium phosphate were impacted. No evidence of loosening or osteolysis was present at 3.6-year follow-up. Impaction bone grafting using an outside mesh and inside cone for defect containment provides a durable reconstruction of tibial bone defects.