Medial patellofemoral ligament reconstruction fails to correct mild patella alta in cases of patellofemoral instability-a case-control study.

PURPOSE: Medial patellofemoral ligament reconstruction (MPFL-R) is the gold standard in patella soft tissue surgery for patellofemoral instability. Although claimed, recent reports indicate that MPFL-R may fail to distalize the patella in mild cases of patella alta. The present study is a retrospective case-control study to compare radiographic patella height between MPFL-R and historical Insall's proximal realignment (IPR) pre- and post-operatively with respect to distalization and assess redislocation rates at a mid-term follow-up. METHODS: Sixty-four patients were age/sex matched (1:1), yielding 32 patients for group 1 MPFL-R (cases) and 32 patients for group 2 IPR (controls). Insall-Salvati, Blackburne-Peel and Caton-Deschamps indices were analyzed for differences pre- and post-operatively. An additional inter-rater reliability analysis was performed by means of intra-class correlation (ICC). Redislocation rates were considered as treatment failures in this study. RESULTS: ICC was excellent for all three patella indices. MPFL-R failed to show significant differences if compared to IPR with respect to distalization in mild stages of patella alta. Moreover, redislocation rates significantly favored MPFL-R (3.1%) over IPR (12.5%; p < 0.0001). CONCLUSIONS: MPFL-R has become a popular option to restore native patellofemoral biomechanics after ligament rupture. However, the procedure's potential to correct concomitant patella alta should not be overestimated and indications considered carefully.

Comparison of two-stage revision arthroplasty and intramedullary arthrodesis in patients with failed infected knee arthroplasty.

BACKGROUND: Failed total knee arthroplasty (TKA) with significant bone loss and compromised soft-tissues is challenging and the final results are often inferior to patient's expectation. The objective of this study was to present a comparison of outcomes in patients with failed infected TKA treated with two-stage revision TKA or knee arthrodesis and to assess clinical and functional results, implant survival and infection recurrence. The hypothesis was that an arthrodesis may result in beneficial effects on patients' outcome. METHODS: Clinical data of 81 patients with periprosthetic joint infection (PJI) of the knee joint were collected and analyzed retrospectively. Between 2008 and 2014, a total of 36 patients had been treated within a two-stage exchange procedure and reimplantation of a modular intramedullary arthodesis nail and 45 patients with revision TKA. Patients were treated according to the same structured treatment algorithm. Clinical and functional evaluation was performed using the Oxford knee score (OKS) and the visual analogue scale (VAS). RESULTS: The mean follow-up was 32.9 ± 14.0 months. The rate of definitely free of infection at last follow-up in the arthrodesis group was 32 of 36 (88.9%) and 36 of 45 (80.0%) in the revision TKA group (p = 0.272). Mean VAS for pain in the arthrodesis group was 3.1 ± 1.4 compared to 3.2 ± 1.6 in the revision TKA group (p = 0.636). The OKS in the arthrodesis group was 38.7 ± 8.9 and 36.5 ± 8.9 (p = 0.246) in patients with revision TKA. Rate of revisions in the revision-TKA group was 2.8 ± 3.7 compared to 1.2 ± 2.4 in the arthrodesis group (p = 0.021). CONCLUSION: Treatment of PJI needs a distinct therapy with possible fallback strategies in case of failure. A knee arthrodesis is a limb salvage procedure that showed no significant benefits on the considered outcome factors compared to revision TKA but is associated with significantly lower revision rate. After exhausted treatment modalities, a knee arthrodesis should be considered as an option in selected patients. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Pre-operative intra-articular deep tissue sampling with novel retrograde forceps improves the diagnostics in periprosthetic joint infection.

BACKGROUND: Histopathological tissue analysis is a key parameter within the diagnostic algorithm for suspected periprosthetic joint infections (PJIs), conventionally acquired in open surgery. In 2014, Hügle and co-workers introduced novel retrograde forceps for retrograde synovial biopsy with simultaneous fluid aspiration of the knee joint. We hypothesised that tissue samples acquired by retrograde synovial biopsy are equal to intra-operatively acquired deep representative tissue samples regarding bacterial detection and differentiation of periprosthetic infectious membranes. METHOD: Thirty patients (male n = 15, 50%; female n = 15, 50%) with 30 suspected PJIs in painful total hip arthroplasties (THAs) were included in this prospective, controlled, non-blinded trial. The results were compared with intra-operatively obtained representative deep tissue samples. RESULTS: In summary, 27 out of 30 patients were diagnosed correctly as infected (17/17) or non-infected (10/13). The sensitivity to predict a PJI using the Retroforce® sampling forceps in addition to standard diagnostics was 85%, the specificity 100%. CONCLUSIONS: Retrograde synovial biopsy is a new and rapid diagnostic procedure under local anaesthesia in patients with painful THAs with similar histological results compared to deep tissue sampling.

Thirteen year follow-up of a cementless femoral stem and a threaded acetabular cup in patients younger than fifty years of age.

PURPOSE: Compared to older patients undergoing total hip arthroplasty (THA) younger patients are considered to be more active, thereby exposing the implant to significantly higher loads over a much longer period of time. Additionally, cases of secondary osteoarthritis caused by hip dysplasia, femoral head necrosis or rheumatic diseases are much more frequent than among the average patient population. Therefore, durable implant fixation and low wear rates are extremely important to achieve good long-term implant survival in this group of patients. OBJECTIVE: The aim of this retrospective study was to evaluate the mid- to long-term survival of a cementless femoral stem (Zweymüller® SL stem) and a threaded cup (Bicon SL®) in patients younger than 50 years of age. METHODS: Therefore, a consecutive series of 100 patients (111 hips) aged 50 years or younger (range: 30 to 50 years) was analysed at a mean follow up of 13.5 years. Follow-up assessment included physical examination and radiographic workup. Hip disability osteoarthritis and outcome score (HOOS) and Harris hip score (HHS) were used to evaluate the pre- and post-operative functional outcome, respectively. Patient satisfaction with the surgical result was assessed by standardized questionnaires. RESULTS: The overall survival rate with any revision as endpoint was 96.8 % (95 % CI: 90.5 % to 98.9 %) at ten years. Gender, operation time and the occurence of osteolyses had no influence on joint function or patient satisfaction. We recorded an overall failure rate of 7.4 % (six cases). In four cases (5 %) the prosthesis had to be revised due to aseptic loosening of the cup after 12 years, eight years, 12 years and 11 years, in one case (1.2 %) recurrent luxation led to a revision operation (acetabular cup and head) after three years of primary implantation. In one case an implant failure was recorded (acetabular cup breakage after eight years of implantation). We recorded the occurence of asymptomatic radiolucent lines of the cup in 21 % and of the stem in 35 % in our series. The HOOS was influenced by the presence or abscence of radiolucent lines of the stem. Patients with radiolucent lines of the stem had a median HOOS score of (74 points) compared to those without radiolucent lines (89 points). Other factors, such as "diagnosis led to operation" and "previous operations" had no influence on the HHS and HOOS. CONCLUSION: Our study demonstrates excellent long-term survival of cementless femoral stem in combination with a threaded cup in young patients undergoing total hip arthroplasty.

Polymicrobial infections reduce the cure rate in prosthetic joint infections: outcome analysis with two-stage exchange and follow-up ≥two years.

PURPOSE: Prosthetic joint infections (PJI) are a serious and challenging complication after total joint arthroplasty. According to the literature, most PJI are monomicrobial infections caused by gram-positive cocci. The number of polymicrobial PJI might be underrepresented in the literature and only limited data are available regarding the outcome of polymicrobial PJI. Our hypothesis was that polymicrobial PJI are associated with a reduced cure rate compared with monomicrobial PJI. METHODS: Routine clinical data were collected and analysed retrospectively as anonymised, aggregated data. A total of 77 consecutive patients with 77 confirmed PJI and proven infectious organism of the hip and knee joint treated within a two-stage exchange concept and a follow-up ≥ two years were investigated. Detection of the infectious organism was based on multiple microbiological cultures taken intra-operatively. Superficial wound swabs or swabs from sinus tracts were not taken into account. Data were grouped into polymicrobial and monomicrobial PJI. The main outcome variable was "definitively free of infection after two years" as published. Second, we considered several variables as potential confounders or as risk factors. RESULTS: A total of 42 men and 35 women with 46 infected total hip arthroplasties and 31 infected total knee arthroplasties were evaluated. In 37 (46.6 %) of our 77 patients a polymicrobial PJI could be detected. We found a significant association between polymicrobial PJI and the outcome parameter definitively free of infection after two years with an odds ratio (OR) of 0.3 [95 % confidence interval (CI) 0.1-1.0]. The rate of patients graded as definitively free of infection after two years was 67.6 % for polymicrobial infections vs. 87.5 % for monomicrobial infections. The American Society of Anesthesiologists (ASA) score (OR 0.4, 95 % CI 0.2-1.0, p = 0.062) was identified as a borderline significant covariable. CONCLUSIONS: Our data suggest that polymicrobial PJI might be underrepresented in the current literature. Additionally, the presence of multiple infectious organisms is associated with a reduced rate after two years with 67.6 vs 87.5 % for monomicrobial infections. Special attention and extra care should be considered for these patients.

Outcome Predictors in Prosthetic Joint Infections--Validation of a risk stratification score for Prosthetic Joint Infections in 120 cases.

Prosthetic joint infections are a major challenge in total joint arthroplasty, especially in times of accumulating drug resistancies. Even though predictive risk classifications are a widely accepted tool to define a suitable treatment protocol a classification is still missing considering the difficulty in treating the -causative pathogen antibiotically. In this study, we present and evaluate a new predictive risk stratification for prosthetic joint infections in 120 cases, treated with a two-stage exchange. Treatment outcomes in 120 patients with proven prosthetic joint infections in hip and knee prostheses were regressed on time of infection, systemic risk factors, local risk factors and the difficulty in treating the causing pathogen. The main outcome variable was "definitely free of infection" after two years as published. Age, gender, and BMI were included as covariables and analyzed in a logistic regression model. 66 male and 54 female patients, with a mean age at surgery of 68.3 years±12.0 and a mean BMI of 26.05±6.21 were included in our survey and followed for 29.0±11.3 months. We found a significant association (p<0.001) between our score and the outcome parameters evaluated. Age, gender and BMI did not show a significant association with the outcome. These results show that our score is an independent and reliable predictor for the cure rate in prosthetic joint infections in hip and knee prostheses treated within a two-stage exchange protocol. Our score illustrates, that there is a statistically significant, sizable decrease in cure rate with an increase in score. In patients with prosthetic joint infections the validation of a risk score may help to identify patients with local and systemic risk factors or with infectious organisms identified as "difficult to treat" prior to the treatment or the decision about the treatment concept. Thus, appropriate extra care should be considered and provided.

Meta-analysis on biomechanical properties of meniscus repairs: are devices better than sutures?

PURPOSE: Meniscal repair devices have been extensively tested during the past decades as reported in the literature. Reviewing the different meniscal repair devices and sutures with their respective biomechanical properties. METHODS: For this meta-analysis, we conducted a systematic online search using PubMed, EMBASE, CCTR, and CINAHL using the search terms Meniscus OR Meniscal AND Biomechanics AND Repair). Load-to-failure (LtF), stiffness, and cyclic outcome measures were extracted independently and in duplicate. The systematic search revealed 841 manuscripts in total. After exclusion of duplicates and irrelevant publications, 41 studies remained for final analysis. The studies were published in English and German from 1995 to 2013. Due to differing cyclic force protocols, cyclic outcomes had to be excluded. RESULTS: Overall, sutures had a higher LtF [suture: 87.7 ± 0.3 N (weighted mean ± standard error), device: 56.3 ± 0.1 N] and stiffness (suture: 8.9 ± 0.04 N/mm, device: 8.6 ± 0.04 N/mm) than devices, both p < 0.05. In LfT testing, PDS 0 Vertical (145.0 ± 8.1 N), OrthoCord 2-0 (143.6 ± 11.3 N), and Ethibond No 0 Vertical (133.4 ± 7.7 N) were the strongest sutures and Meniscal Viper (140.9 ± 5.1 N), MaxFire Vertical (136.2 ± 11.3 N), and FasT-Fix Vertical (115.2 ± 1.6 N) were the strongest devices. Second-generation devices were significantly stronger and stiffer than first-generation devices (p < 0.001). CLINICAL RELEVANCE: Suture repair remains the gold standard with a vertically oriented suture configuration showing superior LtF values compared to a horizontal configuration. Nevertheless, some meniscal repair devices have similar biomechanical properties to suture repairs. Both suture repairs and devices have a place in meniscal restoration. LEVEL OF EVIDENCE: None, meta-analysis of controlled laboratory studies.

Acetabular defect reconstruction in revision hip arthroplasty with a modular revision system and biological defect augmentation.

PURPOSE: Revision of failed total hip arthroplasty with severe acetabular bone loss represents a rare but challenging problem. Anatomic reconstruction with biological defect augmentation as solid bone transplants or cancellous bone restores bone stock while providing good component stability. The objective of this study was to present short- to mid-term results of revision total hip arthroplasty with a modular ring system in a consecutive series of patients with severe acetabular bone loss. METHODS: We retrospectively reviewed 39 consecutive patients (39 hips) with severe acetabular bone loss (Paprosky type 3 A and 3 B) reconstructed with revision total hip arthroplasty using the cementless modular ring system MRS-Titan®. The MRS-Titan® consists of independent ring systems that are adapted modularly to the defect situation. Combined with acetabular defect reconstruction by using cancellous bone in impaction grafting technique, the MRS-Titan® system offers a cement-free revision system that enables defect-adapted customization to individual anatomic matters, bridging of the acetabular bone defect and reconstruction of the centre of rotation. Initial stability of the implant was obtained by screw fixation. Harris hip score and sequential radiographs were used to evaluate clinical and radiographic results. RESULTS: At an average follow up of 31 months (range 12-69 months) 33 of 39 (84.6 %) of the implants were considered radiographically stable without signs of acetabular migration of more than 2 mm in the horizontal or vertical direction, implant rotation or screw breakage. Complications included six implant failures (15 %). We recorded one aseptic loosening of the MRS prosthesis after 20 months. Five patients (12.8 %) had to undergo revision surgery because of periprosthetic joint infection. Two patients had a dislocation postoperatively. The mean Harris hip score improved from 27 ± 14 points preoperatively to 76 ± 15 points at the time of last follow up. CONCLUSION: By achieving stable implant fixation and providing potential for biological fixation, treatment of severe acetabular bone loss in revision total hip arthroplasty with the modular ring system MRS-Titan provides a durable solution with good clinical and radiographic results and allows us to accomplish major goals of reconstruction.

Validation of the Charlson comorbidity index in patients undergoing revision total hip arthroplasty.

PURPOSE: The Charlson comorbidity index (CCI) was developed to quantify the influence of comorbidities on survival. The age-related CCI respects patients' age as an additional risk factor. There are several studies available based on administrative data regarding functional outcome, implant survival, resource use and length of hospital stay in patients undergoing primary total hip arthroplasty (THA). To date, there is a lack of knowledge regarding the correlation of the CCI and the age-related CCI in case of revision total hip arthroplasty (RTHA). OBJECTIVE: Our objective was to validate the influence of the CCI and age-related CCI in patients undergoing RTHA regarding complication rate, resource use implant survival and mortality rate. METHODS: Between October 2007 and November 2012, 142 consecutive patients undergoing RTHA were included in this retrospective study. Routine clinical data were collected and analysed as anonymized aggregated data. In accordance to CCI and age-related CCI the rate of complications (internal medical and surgical complications), the length of hospital stay and the need for ICU treatment and the mortality rate was evaluated. Kaplan-Meier survivorship was used to determine implant survival. RESULTS: Twenty-one patients (15%) had a low risk CCI, 59 patients (41%) a moderate risk CCI and 62 patients (44%) a high risk CCI. The mean follow-up was 27 months (range 24-70 months). In total, we recorded 57 complications (40%), of which 45 were surgical (79%) and 12 were internal medical complications (21%). Twenty-four patients (17%) had to undergo revision surgery. CCI and age-related CCI had no influence regarding implant survival. We recorded a significant influence of the age-related CCI in regard to the necessity of postoperative intensive care unit stay and the length of total hospital stay. Further we recorded a significant influence of the CCI and the age-related CCI regarding postoperative complications and internal complications, postoperative dislocation and the need for surgical revision. CONCLUSION: In summary, we conclude that the CCI and the age-related CCI are strong predictors regarding complication rate in patients undergoing RTHA. In a short- to mid-term follow-up, no influence on implant survival is detectable.

CT-guided infiltration saves surgical intervention and fastens return to work compared to anatomical landmark-guided infiltration in patients with lumbosciatica.

BACKGROUND: Infiltration procedures are a common treatment of lumbar radiculopathy. There is a wide variety of infiltration techniques without an established gold standard. Therefore, we compared the effectiveness of CT-guided transforaminal infiltrations versus anatomical landmark-guided transforaminal infiltrations at the lower lumbar spine in case of acute sciatica at L3-L5. METHODS: A retrospective chart review was conducted of 107 outpatients treated between 2009 and 2011. All patients were diagnosed with lumbar radiculopathic pain secondary to disc herniation in L3-L5. A total of 52 patients received CT-guided transforaminal infiltrations; 55 patients received non-imaging-guided nerve root infiltrations. The therapeutic success was evaluated regarding number of physician contacts, duration of treatment, type of analgesics used and loss of work days. Defined endpoint was surgery at the lower lumbar spine. RESULTS: In the CT group, patients needed significantly less oral analgesics (p < 0.001). Overall treatment duration and physician contacts were significantly lower in the CT group (p < 0.001 and 0.002) either. In the CT group, patients lost significant fewer work days due to incapacity (p < 0.001). Surgery had to be performed in 18.2 % of the non-imaging group patients (CT group: 1.9 %; p = 0.008). CONCLUSION: This study shows that CT-guided periradicular infiltration in lumbosciatica caused by intervertebral disc herniation is significantly superior to non-imaging, anatomical landmark-guided infiltration, regarding the parameters investigated. The high number of treatment failures in the non-imaging group underlines the inferiority of this treatment concept.

Evidence of MRSE on a gentamicin and vancomycin impregnated polymethyl-methacrylate (PMMA) bone cement spacer after two-stage exchange arthroplasty due to periprosthetic joint infection of the knee.

BACKGROUND: Periprosthetic joint infections (PJI) are often treated by two stage exchange with the use of an antibiotic impregnated spacer. Most of the two-stage exchange algorithms recommend the implantation of an antibiotic-impregnated spacer during the first stage for a period of 2-24 weeks before reimplantation of the new prosthesis. For the spacer to have a therapeutic effect, the local antibiotic concentration must be greater than the minimal inhibition concentration (MIC) against the pathogens causing the PJI. It must remain so for the entire spacer period, otherwise recurrence of infection or resistances might occur. The question as to whether a sufficient concentration of antibiotics in vivo is reached for the entire spacer period has not been answered satisfactorily. CASE PRESENTATION: We here present a case of a histologically confirmed chronic PJI 20 month after primary arthroplasty. The primary knee arthroplasty was performed due to osteoarthritis of the joint. Initial assessment did not detect a causative pathogen, and two stage exchange with a vancomycin-gentamycin impregnated spacer was performed. At the time of reimplantation, sonication of the explanted spacer revealed a multi-resistant strain of staphylococcus epidermidis on the device and in the joint. Adaption of the therapy and prolonged treatment successfully eradicated the infection. CONCLUSION: According to the authors' knowledge, the case presented here confirms for the first time the surface contamination (proven through sonication) of a vancomycin-/gentamicin- impregnated Vancogenx®-spacer with a MRSE after ten weeks of implantation.This case study demonstrates the difficulties still associated with the diagnostics of PJI and the published different two stage treatment regimes with the use of antibiotic impregnated spacers.

Management of severe periacetabular bone loss combined with pelvic discontinuity in revision hip arthroplasty.

PURPOSE: Revision of failed total hip arthroplasty with massive acetabular bone loss resulting in pelvic discontinuity represents a rare but challenging problem. The objective of this study was to present short to mid-term results of revision total hip arthroplasty with a custom-made acetabular implant in a consecutive series of patients with pelvic discontinuity. METHODS: We retrospectively reviewed 18 consecutive patients with massive acetabular bone loss (Paprosky Type 3B) resulting in pelvic discontinuity reconstructed with revision total hip arthroplasty using a custom-made acetabular component. The prosthesis was created on the basis of a thin-cut 1-mm computed tomography (CT) scan of the pelvis. Initial stability of the implant was obtained by screw fixation. Harris hip score and sequential radiographs were used to evaluate the clinical and radiographic results. RESULTS: At an average follow up of 30 months (range 17-62 months) 16 of 18 (88.9%) custom-made implants were considered radiographically stable without signs of acetabular migration of more than 2 mm in the horizontal or vertical direction, implant rotation or screw breakage. Complications included two periprosthetic joint infections treated with explantation of the implant. Three patients had recurrent dislocations postoperatively. The mean Harris hip score improved from 28 ± 12 points preoperatively to 69 ± 13 points at the time of last follow up. CONCLUSION: Treatment of acetabular bone loss and pelvic discontinuity with a custom-made acetabular component can provide a durable solution with good clinical and radiographic results.

Lipopolysaccharide-binding protein: a valuable biomarker in the differentiation between periprosthetic joint infection and aseptic loosening?

PURPOSE: The pre-operative differentiation between periprosthetic joint infection (PJI) and aseptic loosening after total hip (THA) or knee (TKA) arthroplasty is essential for successful therapy and relies in part on the use of molecular markers. The objective of this study was to assess serum levels of lipopolysaccharide-binding protein (LBP) as a diagnostic tool for PJI and to compare its accuracy with standard tests. METHODS: One hundred and twenty patients presenting with a painful TKA or TKA with indication for surgical revision were included in this prospective, controlled, clinical trial at a single centre. Pre-operative blood and serum samples were collected and analysed for white blood cell (WBC) count, C-reactive protein (CRP) and LBP. The definite diagnosis of periprosthetic joint infection was determined on the basis of clinical, microbiological and histopathological examination. RESULTS: LBP showed significantly higher values in PJI compared with aseptic loosening (p < 0.001) and control (p < 0.001), with a specificity of 66% and a sensitivity of 71% at a cutoff value of >7 ng/ml. In combination with CRP, the positive predictive value for PJI was at 0.67; negative predictive value with both negative was at 0.77. DISCUSSION: Patients with PJI have elevated serum levels of LBP when compared with patients with aseptic loosening. The use of LBP in serum appears not to be a more accurate marker than CRP level in serum for detecting PJI. On the basis of these results, we cannot recommend the sole use of LBP for differentiating PJI and aseptic loosening following THA and TKA.

Uncemented femoral revision arthroplasty using a modular tapered, fluted titanium stem: 5- to 16-year results of 163 cases.

BACKGROUND AND PURPOSE: Due to the relative lack of reports on the medium- to long-term clinical and radiographic results of modular femoral cementless revision, we conducted this study to evaluate the medium- to long-term results of uncemented femoral stem revisions using the modular MRP-TITAN stem with distal diaphyseal fixation in a consecutive patient series. PATIENTS AND METHODS: We retrospectively analyzed 163 femoral stem revisions performed between 1993 and 2001 with a mean follow-up of 10 (5-16) years. Clinical assessment included the Harris hip score (HHS) with reference to comorbidities and femoral defect sizes classified by Charnley and Paprosky. Intraoperative and postoperative complications were analyzed and the failure rate of the MRP stem for any reason was examined. RESULTS: Mean HHS improved up to the last follow-up (37 (SD 24) vs. 79 (SD 19); p<0.001). 99 cases (61%) had extensive bone defects (Paprosky IIB-III). Radiographic evaluation showed stable stem anchorage in 151 cases (93%) at the last follow-up. 10 implants (6%) failed for various reasons. Neither a breakage of a stem nor loosening of the morse taper junction was recorded. Kaplan-Meier survival analysis revealed a 10-year survival probability of 97% (95% CI: 95-100). INTERPRETATION: This is one of the largest medium- to long-term analyses of cementless modular revision stems with distal diaphyseal anchorage. The modular MRP-TITAN was reliable, with a Kaplan-Meier survival probability of 97% at 10 years.

Impaction grafting in the femur in cementless modular revision total hip arthroplasty: a descriptive outcome analysis of 243 cases with the MRP-TITAN revision implant.

BACKGROUND: We present a descriptive and retrospective analysis of revision total hip arthroplasties (THA) using the MRP-TITAN stem (Peter Brehm, Weisendorf, GER) with distal diaphyseal fixation and metaphyseal defect augmentation. Our hypothesis was that the metaphyseal defect augmentation (Impaction Bone Grafting) improves the stem survival. METHODS: We retrospectively analyzed the aggregated and anonymized data of 243 femoral stem revisions. 68 patients with 70 implants (28.8%) received an allograft augmentation for metaphyseal defects; 165 patients with 173 implants (71.2%) did not, and served as controls. The mean follow-up was 4.4 ± 1.8 years (range, 2.1-9.6 years). There were no significant differences (p > 0.05) between the study and control group regarding age, body mass index (BMI), femoral defects (types I-III as described by Paprosky), and preoperative Harris Hip Score (HHS). Postoperative clinical function was evaluated using the HHS. Postoperative radiologic examination evaluated implant stability, axial implant migration, signs of implant loosening, periprosthetic radiolucencies, as well as bone regeneration and resorption. RESULTS: There were comparable rates of intraoperative and postoperative complications in the study and control groups (p > 0.05). Clinical function, expressed as the increase in the postoperative HHS over the preoperative score, showed significantly greater improvement in the group with Impaction Bone Grafting (35.6 ± 14.3 vs. 30.8 ± 15.8; p ≤ 0.05). The study group showed better outcome especially for larger defects (types II C and III as described by Paprosky) and stem diameters ≥ 17 mm. The two groups did not show significant differences in the rate of aseptic loosening (1.4% vs. 2.9%) and the rate of revisions (8.6% vs. 11%). The Kaplan-Meier survival for the MRP-TITAN stem in both groups together was 93.8% after 8.8 years. [Study group 95.7% after 8.54 years ; control group 93.1% after 8.7 years]. Radiologic evaluation showed no significant change in axial implant migration (4.3% vs. 9.3%; p = 0.19) but a significant reduction in proximal stress shielding (5.7% vs. 17.9%; p < 0.05) in the study group. Periprosthetic radiolucencies were detected in 5.7% of the study group and in 9.8% of the control group (p = 0.30). Radiolucencies in the proximal zones 1 and 7 according to Gruen occurred significantly more often in the control group without allograft augmentation (p ≤ 0.05). CONCLUSION: We present the largest analysis of the impaction grafting technique in combination with cementless distal diaphyseal stem fixation published so far. Our data provides initial evidence of improved bone regeneration after graft augmentation of metaphyseal bone defects. The data suggests that proximal metaphyseal graft augmentation is beneficial for large metaphyseal bone defects (Paprosky types IIC and III) and stem diameters of 17 mm and above. Due to the limitations of a retrospective and descriptive study the level of evidence remains low and prospective trials should be conducted.

Treating patella instability in skeletally immature patients.

PURPOSE: The purpose of this study was to comprehensively and systematically review the current evidence for orthopaedic treatment of immature and adolescent patients with acute and chronic patellar instability. METHODS: We searched the online databases PubMed, CINAHL, EMBASE, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews for relevant publications on patellar instability. All dates and languages were included. RESULTS: Twenty articles reporting on a total of 456 knees in 425 patients (131 male patients, 294 female patients) followed-up for 56.7 ± 42.2 months on average were included in the analysis. Two studies focused specifically on conservative versus surgical treatment in acute dislocations and reported no difference in outcomes after 7 and 14 years, even in the face of slight trochlear dysplasia. For recurrent instability, we found consistent beneficial effects from surgical stabilization on clinical scores, postoperative stability, and radiographic assessment. There is no evidence for growth disturbance with surgical patellar stabilization in immature patients. CONCLUSIONS: The current best evidence does not support the superiority of surgical intervention over conservative treatment in an acute patellar dislocation. However, anatomic variations and their effect on healing should be considered and included in decision making. In recurrent patellar instability in pediatric and adolescent patients with normal or restored knee anatomy, reconstruction of the medial patellofemoral ligament (MPFL) is the most effective treatment option and can be done safely, together with extensor realignment as needed. LEVEL OF EVIDENCE: Level IV, systematic review of mixed-level studies.

Evaluation of an interdisciplinary therapy algorithm in patients with prosthetic joint infections.

PURPOSE: Current concepts in the treatment of prosthetic joint infections include prosthetic retention and exchange strategies according to published recommendations. A useful algorithm should fit for each type of prosthetic joint infection, even the most complicated situations. We present the outcome of 147 patients with prosthetic joint infections of the hip or the knee joint in an unselected population in clinical routine. METHODS: Between November 2006 and November 2009, 147 consecutive patients with prosthetic joint infections of the hip or knee were treated according to an algorithm based on the concept published by Zimmerli et al. in 2004. Causative organism, duration of infection, patient comorbidities, surgical treatment, antibiotic treatment, and outcome of treatment were analysed retrospectively. According to the criteria duration of infection, stability of prosthesis, local and systemic risk factors, and susceptibility of the causative pathogen, patients were treated either with debridement and retention or a long-interval two-stage procedure. RESULTS: A pathogen could be detected in 82.8% of the patients, gram-positive cocci being most common. Twenty-seven patients were treated with debridement and retention and 120 were treated with a two-stage procedure. In 68 cases difficult-to-treat pathogens could be detected, a polymicrobial infection was found in 51 patients. Definitely free of infection were 71.6% after a two-stage procedure, and 70.4% after debridement and retention. CONCLUSIONS: Our data indicates that the applied algorithm is suitable to be applied as a day-to-day routine, and we confirmed that published results from the literature can be reproduced in an inhomogeneous patient cohort.

Video Based Assessment of Treatment Urgency in Outpatient Orthopaedic and Trauma Patients - a Pilot Trial. / Videobasierte Einschätzung der Behandlungsdringlichkeit - eine Pilotstudie für ambulante Patienten in der Orthopädie und Unfallchirurgie.

INTRODUCTION: When consulting a specialist in orthopaedics and trauma surgery, personal assessment and manual clinical examination by the doctor on site are essential. Nevertheless, implementation of video consultation hours has been made legally easier in Germany. The present pilot study examines the possibility of video-based assessment of the urgency of treatment in outpatient orthopaedic and trauma patients. MATERIALS AND METHODS: Within an ex ante study design, 40 patients with an orthopaedic clinical picture for trauma surgery with elective, urgent or emergency indication were selected from consultation hours. A short questionnaire was filled in based on the information provided and a medical colleague simulated a movement sequence based on the patient information. After modification to the "red flags" and "yellow flags" established in spinal orthopaedics, nine short questions were recorded, which inquire about the urgency of a medical consultation. The video-based movement sequence is based on a 60 s long instruction video in which motor tests and movement sequences are demonstrated: Cervical spine movement in all levels, elevation of the upper extremity, test of the finger-floor distance when "bending forward over-bending", possibility of crouching from standing and getting up again, standing on heels and toes. RESULTS: In 91.1% (n = 328) of the cases, the diagnosis was associated with the same joint or the same pathological entity. In 37.5% (n = 135) of the cases an emergency indication was seen, in 10.8% (n = 39) of the cases an urgent indication and in 51.6% (n = 186) of the cases it was seen to offer an elective indication. 12.5% (n = 45) of the cases were evaluated as "false positives" with regard to an emergency or urgent presentation. This means that the test persons were classified as "emergency" or "urgent", although there was no preventable dangerous course or medical emergency. 18 cases (5%) were evaluated as "false negative". DISCUSSION: The screening questionnaire presented and the short video assessment are technically feasible and practicable method for the initial evaluation in video-based online medical consultation. In addition, the questionnaire presented in combination with the short video assessment was suitable as an instrument for assessing the urgency of the consultation and selecting preventable dangerous processes and acute emergencies. CONCLUSION: The questionnaire, in combination with the short video assessment, is a suitable method for the social distancing requirements during limited accessibility of the medical system. Nevertheless, a false negative rate of 5% is too high to implement the questionnaire presented into daily clinics without further optimisation.

[Minimally invasive tibialis anterior tendon transfer in shuttle technique for the treatment of clubfoot recurrence in adolescent patients]. / Minimalinvasiver Tibialis-anterior-Sehnentransfer in Shuttle-Technik zur Behandlung des Klumpfußrezidivs im Wachstumsalter.

OBJECTIVE: Tibialis anterior transfer in shuttle technique using the tunnelator is an atraumatic surgical technique without injuring the extensor retinaculum. The technique allows for postoperative treatment with pain-adapted full weight-bearing for 6 weeks in a lower leg cast which is simplified compared to the current literature. INDICATIONS: Passive, correctable clubfoot recurrences in the event of muscular imbalance (overbalanced anterior tibial muscle). CONTRAINDICATIONS: Structural movement restrictions of the foot, muscular insufficiency of the anterior tibial muscle, infection or cancerous lesions in the surgical site. SURGICAL TECHNIQUE: Loosen the tibialis anterior muscle at the base of the first metatarsal. Guide the tendon proximally out of the extensor retinaculum, then shuttle the tendon below the retinaculum with the help of the "tunnelator" and transosseous fixation at the lateral cuneiform. POSTOPERATIVE MANAGEMENT: Pain-adapted full weight-bearing in a lower leg walking cast for 6 weeks postoperatively. RESULTS: In the course of a retrospective study, the above-mentioned surgical procedure was carried out in 20 patients (total n = 26 surgeries) between 2013 and 2019. After a follow-up of 12 months, complete correction of the clubfoot relapse was found in 88.5% of cases. There were no general or specific surgical complications.

[Extension osteotomy of the lateral distal femur using the contralateral TomoFix® plate]. / Laterale distale femorale Extensionsosteotomie mit der kontralateralen TomoFix®-Platte.

OBJECTIVE: Supracondylar distal femoral osteotomy. Fixation with the contralateral TomoFix® (Fa. DePuy Synthes, Oberdorf, Switzerland) lateral distal femur plate. Use of the laterally reversed plate to improve the reconstruction of the sagittal anatomical axis of the leg. INDICATIONS: To correct knee flexion contractures with a deficiency of extension >20° at the age of 10 years. CONTRAINDICATIONS: Surgical site infections or tumors. SURGICAL TECHNIQUE: Ventral closed wedge osteotomy of the distal femur. Implantation of the locking compression TomoFix® lateral distal femur plate. POSTOPERATIVE MANAGEMENT: Full weight bearing. RESULTS: In all, 16 distal femoral osteotomies were performed in 9 patients. All patients had knee flexion contraction due to neurological disease. Patients with cerebral palsy showed a better GMFCS (gross motor function classification scale) level after surgery. Hardware was removed after 11.5 months (range: 9-18 months).