Medial augmentation plating of aseptic distal femoral nonunions.

BACKGROUND: Distal femur nonunions are well-recognized contributors to persistent functional disability, with limited data regarding their treatment options. In the current study, we asked whether additional medial augmentation plating is a feasible treatment option for patients with aseptic distal femoral nonunion and intact lateral implants. METHODS: We conducted a single-center, retrospective study including 20 patients treated for aseptic distal femoral nonunion between 2002 and 2017. The treatment procedure included a medial approach to the distal femur, debridement of the nonunion site, bone grafting and medial augmentation plating utilizing a large-fragment titanium plate. Outcome measures were bone-related and functional results, measured by the Hospital for Special Surgery Knee Rating Scale (HSS) and the German Short Musculoskeletal Function Assessment questionnaire (SMFA-D). RESULTS: Eighteen of 20 nonunions showed osseous healing at 8.16 ± 5.23 (range: 3-21) months after augmentation plating. Regarding functional results, the mean HSS score was 74.17 ± 11.12 (range: 57-87). The mean SMFA-D functional index was 47.38 ± 16.78 (range 25.74-71.32) at the last follow-up. Index procedure-associated complications included two cases of persistent nonunion and one case of infection. CONCLUSIONS: According to the assessed outcome measures, augmentation plating is a feasible treatment option, with a high proportion of patients achieving bony union and good functional outcomes and a few patients experiencing complications.

Influence of articular step-off on contact mechanics in fractures of the posterolateral-central tibial plateau - a biomechanical study.

BACKGROUND: The posterior quadrants of the tibial plateau are frequently involved in OTA type C tibial plateau fractures. The biomechanical influence of a residual articular step-off of the posterolateral-central (PLC) segment, which is difficult to visualize intraoperatively, remains unclear. Therefore, aim of this study was to investigate the contact area and stress of the tibial plateau in cases of different articular step-offs of the PLC segment. METHODS: Seven human cadaveric knees were used to simulate articular impressions of the PLC segment with step-offs of 1 mm, 3 mm, and 5 mm. The knees were axially loaded up to 150 N during a total of 25 dynamic cycles of knee flexion up to 90°. Pressure mapping sensors were inserted into the medial and lateral joint compartments beneath the menisci to measure articular contact area and stress. RESULTS: Between 60° and 90° of knee flexion, increasing PLC segment impressions of the tibial plateau led to increasing contact stress and a significantly reduced contact area. The largest decrease in the contact area was 30 %, with an articular step-off of 5 mm (0.003). An increase in contact stress, especially from a 3-mm step-off, was measured, with a doubling of the mean contact stress at 3-mm and 5-mm step-offs and 90° knee flexion (p = 0.06/0.05). CONCLUSION: From a biomechanical point of view, posterior impressions of the PLC segment greater than a 1-mm step-off should be addressed as anatomically as possible, especially in active patients with the need for higher knee flexion angles.

[Resection arthroplasty and arthrodesis in revision shoulder arthroplasty]. / Resektionsarthroplastik und Arthrodese in der Prothesenrevision.

Shoulder arthrodesis and resection arthroplasty can be used as salvage procedures to treat severe complications after shoulder prosthesis failure. for both procedures, the indication and patient selection must be very strict. Shoulder arthrodesis after prosthesis failure can be indicated in young patients in case of chronic neuromuscular dysfunction. Filling the bony defect with either autologous or allogenic material and osteosynthetic primary stability are decisive for a good functional outcome. Aftercare comprises immobilization for 12 weeks and physical load is increased thereafter, depending on the sufficiency of bony consolidation. Resection arthroplasty after shoulder prosthesis failure is mostly reserved for multimorbid patients in case of a chronic infection. Thorough debridement and adequate systemic antibiotic treatment are crucial to achieve bacterial eradication.

[Metal glenoid augmentation in revision arthroplasty]. / Metallische Glenoidrekonstruktion in der Revisionsendoprothetik.

Glenoid implantation in revision arthroplasty of the shoulder remains a technical challenge in the case of severe bone loss. Metal glenoid augmentation and patient-specific glenoid implants represent new treatment options with great potential. Virtual planning techniques allow a differentiated evaluation of the extent of the bone loss and the planning of different augmentation options. Although not clearly defined so far, a patient-specific implant can be indicated if adequate fixation of the base plate in the native bone appears questionable. The planning is carried out with the support of the prostheses manufacturer and the stability is simulated using finite element analysis. A high level of primary stability is achieved by an optimized fitting of the implant into the bony defect. The short-term results are promising. However, in the absence of long-term results and limited options in case of revision, the use of a custom-made glenoid warrants a strict indication.

Does the Implementation of the PRO-IMPLANT Foundation Treatment Algorithm Improve the Outcome of Chronic Periprosthetic Knee Infections? Mid-Term Results of a Prospective Study. / Verbessert die Implementierung des PRO-IMPLANT Foundation Behandlungsalgorithmus die Therapie chronischer periprothetischer Knieprotheseninfektionen? Ergebnisse einer prospektiven Studie.

BACKGROUND: Several treatment options for chronic periprosthetic joint infections have been published in the current literature, with an on-going discussion to determine effective management algorithms. OBJECTIVES: To compare outcomes of the two-stage exchange procedure in revision TKA prior to and after implementation of the PRO-IMPLANT Foundation treatment algorithm. The primary endpoints were defined as (i) revisions during the interval time, (ii) duration of the interval time and (iii) successful PJI eradication. MATERIAL AND METHODS: Between 02/2013 and 09/2016, 122 patients were included in a single-centre cohort analysis. 55 patients were treated according to the previously used algorithm (K1) and 67 according to the PRO-IMPLANT Foundation algorithm (K2). A minimum follow-up period of 3 years was set as the inclusion criterion. Successful eradication of infection was defined in accordance with the consensus criteria by Diaz-Ledezma et al. RESULTS: Successful eradication was achieved in 42 (67%) patients in K1 and 47 (85.5%) in K2 (p ≤ 0.005). The mean interval time was 88 days (range 51 - 353) in K1 and 52 days (range 42 - 126) in K2 (p ≤ 0.005). In K1, a mean of 0.8 (range 0 - 6) revisions were necessary during the interval period compared with 0.5 (range 0 - 4) in K2 (p = 0.066). CONCLUSION: Implementation of the PRO-IMPLANT treatment algorithm led to significant improvement in the outcome of periprosthetic joint infections. During mid-term follow-up, infection eradication was highly successful, with decreases in the interval time as well as the number of revisions.

Factors influencing the outcome after surgical reconstruction of OTA type B and C tibial plateau fractures: how crucial is the restoration of articular congruity?

INTRODUCTION: Only few and inconsistent data about the impact of articular congruity and tolerable residual intraarticular steps and gaps of the joint surface after tibial plateau fractures exist. Therefore, aim of this study was to investigate the correlation between OTA type B and C tibial plateau fracture outcomes and postoperative articular congruity using computed tomography (CT) data. MATERIALS AND METHODS: Fifty-five patients with a mean age of 45.5 ± 12.5 years and treated for 27 type B and 28 C tibial plateau fractures with pre- and postsurgical CT data were included. Primary outcome measure was the correlation of postoperative intraarticular step and gap sizes, articular comminution area, the postoperative medial proximal tibial angle (MPTA), and the Lysholm and IKDC score. Receiver-operating characteristic (ROC) curves were used to determine threshold values for step and gap heights according to the following outcome scores: IKDC > 70; Lysholm > 80. Secondary outcome measures were the correlation of fracture severity, the number of complications and surgical revisions and the outcome scores, as well as the Tegner activity score before injury and at final follow-up. RESULTS: After a mean follow-up of 42.4 ± 18.9 months, the mean Lysholm score was 80.7 ± 13.3, and the mean IKDC score was 62.7 ± 17.6. The median Tegner activity score was 5 before the injury and 4 at final follow-up (p < 0.05). The intraarticular step height, gap size, comminution area and MPTA deviation were significantly negatively correlated with the IKDC and Lysholm scores. The cutoff values for step height were 2.6 and 2.9 mm. The gap size threshold was 6.6 mm. In total, an average of 0.5 ± 0.8 (range 0-3) complications occurred, and on average, 0.5 ± 1.1 (range 0-7) surgical revisions had to be performed. The number of complications and surgical revisions also had negative impacts on the outcome. Neither fracture severity nor BMI or patient's age was significantly correlated with the IKDC or Lysholm score. CONCLUSIONS: Tibial plateau fractures are severe injuries, which lead to a subsequent reduced level of patient activity. Precise reconstruction of the articular surface with regard to intraarticular step and gap size, residual comminution area and joint angle is decisive for the final outcome. Complications and surgical revisions also worsen it. LEVEL OF EVIDENCE: III.

[Augmented primary sutures "internal bracing" following ligamentous elbow dislocation]. / Augmentierte Primärnaht "internal bracing" nach ligamentärer Ellenbogenluxation.

OBJECTIVE: Aim of surgical treatment is the primary stabilization of the unstable elbow following a ligamentous elbow dislocation. INDICATIONS: Ligamentous elbow dislocations are typically accompanied by injuries to the surrounding musculature and collateral ligaments of the elbow joint. Surgical treatment is indicated in case of failure of nonoperative therapy, i.e., when a dislocation can only be prevented in immobilization > 90° and pronation of the elbow or an active muscular centering of the elbow fails after 5-7 days. CONTRAINDICATIONS: Contraindications for a solely "internal bracing" augmented primary suture are generally in the case of accompanying bony injuries in elbow dislocations, extensive soft-tissue injuries, and septic arthritis of the elbow. SURGICAL TECHNIQUE: The augmented primary suture of the elbow is performed using both a lateral (Kocher or Kaplan) and medial (FCU split) approach to the elbow. After reduction of the elbow, the collateral ligaments are first augmented with high-strength polyethylene suture and fixed in the distal humerus together with another high-strength polyethylene augmentation suture. The extensors and flexors are then fixed to the medial and lateral epicondyle, respectively, using suture anchors. POSTOPERATIVE MANAGEMENT: The aim of the postoperative management is early functional exercise of the elbow. The elbow is placed in an elbow brace to avoid varus and valgus load. RESULTS: Between August 2018 and January 2020, a total of 12 patients were treated with an augmented primary suture following unstable ligamentous elbow dislocation. After a mean follow-up of 14 ± 12.7 months, the mean Mayo Elbow Performance Score was 98.5 points with a mean functional arc of 115°. None of the patients reported a recurrent dislocation or persistent instability of the elbow.

Shoulder complaints and incidence of shoulder pathologies after contralateral major amputation in the mid and long-term.

INTRODUCTION: Amputations of the upper extremity are rare but present a life-altering event that is accompanied with considerable restrictions for the affected patients. Even with functional prosthesis, tasks of the amputated limb are usually transferred to the unaffected arm which could result in complaints of the unaffected shoulder in the mid and long term. We therefore aimed to investigate musculoskeletal pain and morphological degenerative changes of the shoulder following a contralateral amputation. MATERIALS AND METHODS: We included all patients with a major amputation treated at our institution with a minimum of three years since the amputation. All patients received an MRI of both shoulders and were investigated using validated scores for the upper extremity and physical activity (SSV, ASES, DASH, GPAQ, SF-36). Results of the MRIs were investigated for morphological changes by two blinded investigators comparing the side of the amputation and the unharmed upper extremity and results were correlated to the time since amputation and their physical activity. RESULTS: A total of 20 patients with a mean age of 56 ± 19.9 years (range, 23-82 years) could be included in the study. The mean time since the amputation was 26.3 ± 19 years (range, 3-73 years). On the unharmed upper extremity, the mean SSV was 61.9 ± 24.6, the mean ASES-Score 54.5 ± 20.3, the Constant-score of 63.7 ± 40.4 and a DASH-score of 47.6 ± 23.8. The MRI of the unharmed shoulder showed significant more full-thickness rotator cuff tears and joint effusion compared to the side of the amputation. Significant differences in the degree of a glenohumeral arthritis, AC-joint arthritis, or partial rotator cuff tears could not be found between shoulders. CONCLUSION: Amputations of the upper extremity are associated with a high disability of the unharmed upper extremity and more full thickness rotator cuff tears compared to the side of the amputation. However, the small number of patients and rotator cuff injuries should be kept in mind when interpreting the data. LEVEL OF EVIDENCE: IV (retrospective case series).

Locking the Taylor Spatial Frame - The effect of three additional longitudinal rods on osteotomy site movements.

BACKGROUND: In clinical practice, even when the fixator is locked, a noticeable laxity of the construct can be observed. This study was designed to measure the stiffness of the fixator and to analyze the movements of the osteotomy site. Furthermore, the effect of three additional longitudinal rods on the locking of the construct was analyzed. METHODS: Five synthetic tibia/fixator models (Model A) were tested under rotational torque (40 Nm) and axial compression (700 N). Three additional rigid rods were subsequently mounted, and the tests were repeated (Model B). The movements of the fixator as well as the osteotomy site were registered by a digital optical measurement system. Load- deformation curves, and so stiffness of the models, were calculated and compared. FINDINGS: Under rotational and axial loadings, Model A was found to be less rigid than Model B (p = 0.034; p = 0.194). Notably, Model A showed a region of laxity around neutral rotational (ΔF = 5 Nm) and axial (ΔF = 16.64 N) loading before a linear deformation trend was measured. Concomitantly, greater osteotomy site movement was measured for Model A than for Model B under full loading (p = 0.05) and within the region of increased laxity (p = 0.042). INTERPRETATION: The fixator showed an element of laxity around neutral axial and rotational loading, which transferred to the bone and led to a notable amount of osteotomy gap movement. Mounting three additional rods increased the stiffness of the construct and therefore reduced the movement of the osteotomy site.

Is the bioactivity of induced membranes time dependent?

PURPOSE: The induced membrane technique (IMT) is a two-stage surgical procedure for reconstruction of bone defects. Bone grafting (second stage of IMT) is recommend after 4-8 weeks assuming the highest bioactivity of IMs. However, larger studies concerning the biology and maturation of IMs and a potential time dependency of the bioactivity are missing. Therefore, aim of this study was the time-dependent structural and cellular characterization of cement spacer IMs concomitantly to an analysis of membrane bioactivity. METHODS: IMs from 60 patients (35-82 years) were obtained at different maturation stages (1-16 weeks). IMs were studied by histology and co-culture with mesenchymal stem cells (MSC). IM lysates were analyzed by ELISA and protein microarray. RESULTS: Increasing vascularization and fibrosis were found in membranes older than 4 and 7 weeks, respectively. MSC grew out from all membranes and all membranes enhanced proliferation of cultured MSC. Osteocalcin and osteopontin (in membrane lysates or induced in MSC by membrane tissue) were found over all time points without significant differences. In contrast to alkaline phosphatase activity, increasing levels of osteoprotegerin were found in membranes. CONCLUSION: The histological structure of IMs changes during growth and maturation, however, biologically active MSC and factors related to osteogenesis are found over all time points with minor changes. Thus, membranes older than 8 weeks exert regenerative capacities comparable to the younger ones. The postulated narrow time frame of 4-8 weeks until bone grafting can be questioned and surgeons may choose timing for the second operation more independently and based on other clinical factors.

Tibiocalcaneal arthrodesis using the Ilizarov fixator in compromised hosts: an analysis of 19 patients.

INTRODUCTION: Salvage of joint destruction of the tibiotalar and subtalar joint with necrosis or infection of the talus in compromised hosts is a challenging problem. In these cases, tibiocalcaneal arthrodesis using the Ilizarov external fixator represents a possible alternative to amputation. This retrospective study presents the results and complications of this salvage procedure. MATERIALS AND METHODS: Between 2005 and 2015, 19 patients were treated with tibiocalcaneal arthrodesis using the Ilizarov external fixator. Ten patients received tibiocalcaneal arthrodesis due to an acute or chronic infection with joint destruction. The other nine patients presented posttraumatic necrosis of the talus or Charcot arthropathy. In addition to demographic data, the time spent in the fixator, the major and minor complications and the endpoint of the consolidation were evaluated retrospectively. Furthermore, clinical outcomes were measured using the modified American Orthopedic Foot and Ankle Society (AOFAS) score. RESULTS: The average time spent in the fixator was 22 (range 14-34) weeks. The average follow-up in 17 patients was 116 (range 4-542) weeks. Two patients were lost to follow-up. Complete osseous consolidation was achieved in 14 out of 19 patients. One patient presented partial consolidation, and in four patients, pseudarthrosis could be detected. The mean modified AOFAS score at the final follow-up was 53 out of 86 possible points. CONCLUSION: Tibiocalcaneal arthrodesis using the Ilizarov fixator is a possible salvage procedure even in compromised hosts. However, the healing rates are below the rates reported in the literature for tibiotalar arthrodesis in comparable clinical situations.

Comparative analysis of clinical outcome and quality of life between amputations and combined bone and flap reconstructions at the lower leg.

PURPOSE: At the lower leg, soft tissue defects with exposed bones, tendons, or hardware require flap coverage. In this retrospective study, we analyzed combined bone and soft tissue reconstructions compared to amputations of the lower leg in a civilian setting. MATERIALS AND METHODS: Patients who underwent combined bone and flap reconstruction (LR) or amputation (LA) of the lower leg were eligible for the study. Bone conditions included fractures and bony defects due to posttraumatic osteomyelitis and non-union. Besides the analysis of the medical history, the study included clinical examination including extremity functional scale (LEFS) and SF-36-questionnaire. RESULTS: LEFS score was significantly higher in the LR group compared to the LA group. Importantly, 42% in the LR group as opposed to 80% in the LA group could not return to their occupation. Mean hospitalization was 119 in the LR and 49 days in the LA group. SF-36 body item scores were significantly higher in the LR group as compared to LA. CONCLUSIONS: Patients undergoing complex extremity reconstructions, including flap transfer to the lower leg have better functionality and higher quality of life than amputated patients. These data emphasize the advantages of these procedures and justify reconstructive efforts for limb salvage. Level of Evidence III.Implications for RehabilitationAmputation and combined bone and flap reconstruction in severe injuries of the lower leg can imply functional disabilities even after successful treatment.Albeit longer hospitalizations, patients with complex reconstructions showed better functional outcomes and had a higher quality of life.Limb salvage showed better functional outcomes and a higher rate in reintegration to work as compared to limb amputation.These data emphasize the importance of complex bone and soft tissue reconstruction in this patient cohort.

Simultaneous septic arthrodesis of the tibiotalar and subtalar joints with the Ilizarov external fixator-an analysis of 13 patients.

PURPOSE: Treatment of joint destruction of the tibiotalar and subtalar joints caused by acute or chronic infections in compromised hosts is a challenging problem. In these cases, simultaneous septic arthrodesis with the use of the Ilizarov external fixator represents a possible alternative to amputation. This case series presents the results and complications of patients with acute or chronic infection of the tibiotalar and subtalar joints. METHODS: Between 2005 and 2015, 13 patients with acute or chronic infections were treated by simultaneous single-stage debridement/arthrodesis of the tibiotalar and subtalar joints. In seven patients, there was a florid infection with fistula formation and soft tissue defects, and in six patients, there was chronic osteomyelitis with closed soft tissue. In addition to the demographic data, the time spent in the fixator, the major and minor complications and the endpoint of consolidation were reviewed. RESULTS: The mean time spent in the fixator was 18 (min 15, max 26) weeks. The mean follow-up time for nine patients was 100 (min 3, max 341) weeks. Complete osseous consolidation of both the tibiotalar and subtalar joints was achieved in 10 patients (77%). In three (23%) patients, there was complete consolidation of one of the joints and partial consolidation of the other joint. CONCLUSION: The Ilizarov external fixator allows for simultaneous arthrodesis of the tibiotalar and subtalar joints in septic joint destruction. However, the healing rates are below the rates reported in the literature for isolated tibiotalar or tibiocalcaneal arthrodesis in comparable clinical situations.

Chronic Pain Following Fracture-Related Surgery: Posttraumatic Rather Than Postsurgical Origin Promotes Chronification-A Prospective Observational Study With 1-Year Follow-up.

BACKGROUND: Chronic posttraumatic/postsurgical pain (CPSP) is common after traumatic or surgical damage. Exposure to both trauma and surgery, with the potential for repeated bone and nerve damage, may increase the risk of CPSP after fracture-related surgery. But the (long-term) incidences of CPSP and neuropathic CPSP and the ensuing burdens are unknown. Therefore, the patients were prospectively assessed within 1 year, and the patient-specific characteristics were explored. METHODS: Between 2017 and 2018, 127 patients (age: 52.9 ± 17.1 years, male: 55.1%) with traumatic fractures needing osteosynthesis (extremities: 91.3%) were assessed posttrauma (before surgery), postsurgery at days 1 to 5, 6 weeks, 3 and 12 months. The primary outcomes are as follows: incidence at 3 and 12 months of CPSP (defined as pain intensity on a numerical rating scale [NRS: 0-10] ≥3), secondary exploration: neuropathic CPSP (NRS ≥3 and Douleur Neuropathique 4 interview [DN4i] score ≥3 [Douleur Neuropathique interview: 0-7]); burden: quality of life (QoL, the EuroQOL five dimensions questionnaire [EQ-5D-3L] descriptive system); and inter alia, the number of analgesics (trial registration: DRKS00011601). RESULTS: The incidence of CPSP was 57.1% (52/91, n/N) at 3 and 42.7% (35/82) at 12 months postsurgery, including neuropathic CPSP 7.7% (4/52) and 17.1% (6/35), respectively. Descriptively, posttraumatic higher pain intensity at rest (difference of 0.9 ± 1.8 NRS) and the need for more frequent analgesics (by 34.3%) were associated with CPSP a year after surgery compared to those without. As soon as week 6, these patients had developed descriptively a 15% more impaired QoL, with 25% more impairment after 1 year. The patients with CPSP presented with at least 1 neuropathic symptom 12 months later in 68.6% (24/35) of cases, mainly with an early posttraumatic occurrence (without fulfilling the definition of neuropathic CPSP). CONCLUSIONS: After early fracture-related surgery, high incidences of CPSP (43%) were prospectively observed 1 year postsurgery, up to approximately 1 in 5 patients who had neuropathic CPSP. At the same time, CPSP was accompanied with an impacted QoL and analgesic dependence, both indicating clinical relevance. Moreover, the high incidence and the early posttraumatic occurrence of more intense pain suggest that the initial fracture-related trauma, rather than the surgical trauma, may predominantly trigger CPSP at Y1 (1 year). Therefore, these exploratory results set the direction of required future research. A future clinical hypothesis might be: treat first what hurts first.

Analysis of bone transport for ankle arthrodesis as a limb salvage procedure for the treatment of septic pilon fracture nonunion.

Septic nonunion of the pilon region with ankle joint infection is challenging for orthopedic surgeons to treat and is associated with a high risk of limb loss. Therefore, the aim of this study was to evaluate the effectiveness of bone transport for ankle arthrodesis in salvaging the limp after septic ankle destruction of the pilon region. We conducted a single-center, retrospective study including 21 patients treated for septic pilon nonunion with accompanying septic ankle destruction via Ilizarov bone transport between 2004 and 2018. In all cases, the complete excision of the nonunion and the resection of the ankle joint were carried out, followed by treating the bone and joint defect with a bone transport into the ankle arthrodesis. In 12/21 patients an additional flap transfer was required due to an accompanying soft tissue lesion. The overall healing and failure rate, final alignment and complications were recorded by the patients' medical files. The bone-related and functional results were evaluated according to the Association for the Study and Application of Methods of Ilizarov (ASAMI) scoring system and a modified American Orthopedic Foot and Ankle Society (AOFAS) scale. After a mean follow-up of 30.9 ± 15.7 months (range 12-63 months), complete bone and soft tissue healing occurred in 18/21 patients (85.7%). The patients had excellent (5), good (7), fair (4), and poor (3) results based on the ASAMI functional score. Regarding bone stock, 6 patients had excellent, 7 good, and 6 fair results. The modified AOFAS score reached 60.6 ± 18 points (range, 29-86). In total, 33 minor complications and 28 major complications occurred during the study period. In 2 cases, a proximal lower leg amputation was performed due to a persistent infection and free flap necrosis with a large soft tissue defect, whereas in one case, persistent nonunion on the docking side was treated with a carbon orthosis because the patient refused to undergo an additional surgery. Bone transport for ankle arthrodesis offers the possibility of limb salvage after septic ankle destruction of the pilon region, with acceptable bony and functional results. However, a high number of complications and surgical revisions are associated with the treatment of this severe complication after pilon fracture.

Three-stage revision arthroplasty for the treatment of fungal periprosthetic joint infection: outcome analysis of a novel treatment algorithm : a prospective study.

AIMS: Fungal periprosthetic joint infections (fPJIs) are rare complications, constituting only 1% of all PJIs. Neither a uniform definition for fPJI has been established, nor a standardized treatment regimen. Compared to bacterial PJI, there is little evidence for fPJI in the literature with divergent results. Hence, we implemented a novel treatment algorithm based on three-stage revision arthroplasty, with local and systemic antifungal therapy to optimize treatment for fPJI. METHODS: From 2015 to 2018, a total of 18 patients with fPJI were included in a prospective, single-centre study (DKRS-ID 00020409). The diagnosis of PJI is based on the European Bone and Joint Infection Society definition of periprosthetic joint infections. The baseline parameters (age, sex, and BMI) and additional data (previous surgeries, pathogen spectrum, and Charlson Comorbidity Index) were recorded. A therapy protocol with three-stage revision, including a scheduled spacer exchange, was implemented. Systemic antifungal medication was administered throughout the entire treatment period and continued for six months after reimplantation. A minimum follow-up of 24 months was defined. RESULTS: Eradication of infection was achieved in 16 out of 18 patients (88.8%), with a mean follow-up of 35 months (25 to 54). Mixed bacterial and fungal infections were present in seven cases (39%). The interval period, defined as the period of time from explantation to reimplantation, was 119 days (55 to 202). In five patients, a salvage procedure was performed (three cementless modular knee arthrodesis, and two Girdlestone procedures). CONCLUSION: Therapy for fPJI is complex, with low cure rates according to the literature. No uniform treatment recommendations presently exist for fPJI. Three-stage revision arthroplasty with prolonged systemic antifungal therapy showed promising results. Cite this article: Bone Jt Open 2021;2(8):671-678.

Sonication in the diagnosis of fracture-related infections (FRI)-a retrospective study on 230 retrieved implants.

BACKGROUND: In fracture-related infections (FRI), both the diagnosis of the infection and the identification of the causative pathogen are crucial to optimize treatment outcomes. Sonication has been successfully used for periprosthetic joint infections (PJI); however, its role in FRI remains unknown. Our aim was to determine the diagnostic accuracy (sensitivity, specificity) of sonicate fluid culture (SFC). The primary objective was to compare SFC with peri-implant tissue culture (PTC) overall and among subgroups using the consensus definition by Metsemakers et al. The secondary objective was to determine the yield of SFC in possible fracture-related infections (PFRI). METHODS: From March 2017 to May 2019, 230 cases of retrieved implants were retrospectively reviewed. To perform sonication, explants were placed in sterile polypropylene jars intraoperatively. After treatment in an ultrasonic bath (Bandelin, Berlin, Germany), sonicate fluid was incubated into blood culture bottles, and conventional culturing was eventually performed. Sensitivity and specificity were determined using two-by-two contingency tables. McNemar's test was used to compare proportions among paired samples while Fisher's exact test was used for comparison between categorical variables. RESULTS: Of the 230 cases, 107 were identified as FRI, whereas 123 were aseptic revision cases (ARC). Of the latter, 105 were labeled as PFRI. Sensitivity of SFC was higher in comparison with PTC, although this did not reach statistical significance (90.7% vs. 84.1%; p = .065). The specificity of SFC was significantly lower than that of PTC (73.2% vs. 88.6%; p = .003). In PFRI, SFC yielded significantly more positive results than PTC (33/105 vs. 14/105; p = .003). Overall, 142 pathogens were identified by SFC, whereas 131 pathogens were found by PTC. CONCLUSIONS: We found that sonication of fracture fixation devices may be a useful adjunct in FRI, especially in "low-grade" infections lacking confirmatory clinical criteria. Standardized diagnostic protocols are warranted in order to further optimize the diagnostic accuracy.

Reconstruction of Septic Tibial Bone Defects With the Masquelet Technique and External Ring Fixation-A Low Healing Rate and High Complication and Revision Rates.

OBJECTIVES: To evaluate the results of a series of septic tibial bone defects treated with the Masquelet technique and external ring fixation as a standardized treatment procedure. DESIGN: Retrospective study. SETTING: Level one trauma center. PATIENTS/PARTICIPANTS: All patients 18 years of age or older with septic diaphyseal bone defects of the tibia who underwent induced membrane treatment with ring fixation at our institution between June 1, 2012, and November 31, 2017. INTERVENTION: Staged management as described by Masquelet using an external ring fixator for definitive fixation. MAIN OUTCOME MEASUREMENTS: Bony healing at the last follow-up and the time to healing in months. Functional results were assessed according to the scoring system of the Association for the Study and Application of Methods of Ilizarov. The secondary outcome measures were treatment failure and complications. RESULTS: Thirty-one patients were treated, with a mean follow-up period of 33 months (range, 13-69 months). Overall, among 14 patients assessed as having achieved bone healing, an average of 3.7 surgical revisions were required. The mean healing time was 15.5 months (range, 6-49 months). According to the Association for the Study and Application of Methods of Ilizarov criteria, 7 patients were rated as "excellent" and 6 patients were rated as "good"; one patient showed "poor" functional results. A total of 17 cases of treatment failure and 36 complications were detected. CONCLUSIONS: The combination of the Masquelet technique and external fixation yielded a low healing rate and was associated with a significant number of cases of treatment failure. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Anatomical repair and ligament bracing of Schenck III and IV knee joint dislocations leads to acceptable subjective and kinematic outcomes.

PURPOSE: The aim of this study was to analyze the outcomes of anatomical repair and ligament bracing for Schenck III and IV knee dislocation (KD). METHODS: The results of 27 patients (15 and 12 cases of Schenck III and IV KD, respectively) after a mean follow-up of 18.1 ± 12.1 months (range 6-45 months) were retrospectively reviewed. Twenty-two patients suffered high-kinetic-energy accidents, whereas five patients suffered ultralow-velocity (ULV) trauma due to obesity. The outcome measures were the Lysholm score, Hospital for Special Surgery (HSS) knee score, Knee Society Score (KSS), Knee Injury and Osteoarthritis Outcome Score (KOOS) and Short Form 36 (SF-36) score. A kinematic 3D gait analysis with five walking trials was performed to compare the patients and healthy controls. RESULTS: The mean KSS, HSS score, Lysholm score, and KOOS were 77.4 ± 14.4, 84.6 ± 11.2, 81.5 ± 10.4, and 67.3 ± 16.8, respectively. No intra- or postoperative complications occurred. The mean range of motion deficiency compared to the healthy side was 24.4 ± 18.5°. Ten patients had first-degree residual laxity of the anterior cruciate ligament; 12 and 2 patients had first- and second-degree residual laxity of the collateral ligament, respectively. Five patients underwent additional arthroscopic arthrolysis due to arthrofibrosis at an average of 6.2 ± 1.9 months (range 4-9 months) after the initial surgery. The 3D gait analysis showed no major differences in joint stability or movement between the patients and healthy controls. Only the ULV trauma patients had significantly lower outcome scores and showed larger kinematic deviations in joint movement during the gait analysis. CONCLUSION: Anatomical repair with ligament bracing is a suitable surgical procedure in the treatment of KD and provides evidence in clinical practice with the benefit of early, definitive repair and preservation of the native ligaments. Patients reach acceptable subjective and objective functional outcomes, including mainly normalized gait patterns during short-term follow-up, with only minor changes in kinematics and spatial-temporal characteristics. Obese patients who suffered ULV trauma showed significantly inferior outcomes with larger deviations in joint kinematics. LEVEL OF EVIDENCE: Level III.