Pain levels during distraction osteogenesis with lengthening nails in 168 cases.

PURPOSE: To firstly examine the pain levels during distraction osteogenesis (DO) with lengthening nails (LN) in a large sample. METHODS: A total of 168 cases underwent DO of the tibia or femur with five different models of LN. Under a standardized medical regime, daily pain levels were noted as nominal rating scale (NRS) score (0-10) during the distraction phase. NRS scores and several potential influence factors (LN model, bone, approach, side, age, gender) were evaluated. RESULTS: The mean distraction length was 39.1 ± 14.4 mm. The average NRS score decreased from postoperative day 1 with 2.84 nonlinearly by 1.03 points (36.3%) over the course of 62 days to an average score of 1.81. The mean decrease during the first thirty days was 0.67(23.6%). Subgroup analysis did not reveal any influence factors. CONCLUSION: Pain levels during the distraction phase are overall low, continuously decreasing, and well manageable with mostly non-opioid analgesics.

[Transverse distraction osteogenesis : New chances for limb salvage?] / Transverse Kallusdistraktion : Neue Chancen für den Extremitätenerhalt?

Distraction osteogenesis (DO) is a technique that can be successfully used to treat leg length discrepancies and to reconstruct long defects of bone. By gradual distraction of the bone fragments by approximately 1 mm per day, hypervascularization and an increased bone healing potential (growth stimulus) occur. So far, DO has almost exclusively been used longitudinally to generate new biologically active bone. Chronic wounds, ulcers and osteitis, especially in the region of the foot, are always a challenge for the treating surgeon, since treatment is tedious, the outcome uncertain and associated with possible loss of the extremity. Transverse distraction osteogenesis (tDO) now uses the growth stimulus of the DO translationally to treat distally located, chronic wounds and thus leads to accelerated wound healing. At the end of the 5­week treatment, the transversely distracted fragment, located far proximal to the chronic wound, is back in its original location. The biological stimulus has a long-lasting effect, longer than the tDO itself. Further investigations into the mechanisms of action and treatment outcomes of tDO are required. If the previous results are confirmed, tDO may become a game changer and enable the limb salvage for a large proportion of findings that previously required amputation.

[Reconstruction of large osteochondral defects of the distal femur and proximal tibia : Adaptation of fresh frozen allografts using 3D-printed models]. / Rekonstruktion großer osteochondraler Defekte des distalen Femurs und der proximalen Tibia : Anpassung frisch gefrorener Allografts unter Zuhilfenahme 3D-gedruckter Kunststoffmodelle.

The reconstruction of large osteochondral defects is still a challenge in musculoskeletal surgery. Fresh frozen allografts are a frequently used resource for the treatment of such tissue defects. Furthermore, 3D-printed models enable multiple options in the preoperative planning and intraoperative adaptation of the allografts, so that healing is optimal and the best functional outcome for the patient is achieved.

[Locking plate fixation of distal periprosthetic femoral fractures : Clinical outcome and mortality]. / Winkelstabile Plattenosteosynthese bei distalen periprothetischen Femurfrakturen : Klinisches Outcome und Mortalität.

BACKGROUND: The care of distal periprosthetic femoral fractures (PFF) is becoming a major interdisciplinary challenge due to demographic developments. The operative treatment is often performed (depending on the type of fracture) by means of locking plate fixation (LPF), although little data on the clinical outcome exist by now. The aim of the study is to identify risk factors for a poor outcome and increased mortality METHODS: In this retrospective study, 36 cases with distal PFF were examined. Exclusively treatment with LPF were included. Relevant previous illnesses (ASA score, Charlson index), fracture morphology and major complications were recorded as well as 1- and 3- year mortality. The clinical outcome was detected by using the Lysholm score. RESULTS: The 1- and 3- year mortality were 9% and 26% - exclusively affecting ASA 3 and 4 patients. The Lysholm Score showed a high variability (65 ± 27 points) with higher values in the ASA 1-2 subgroup (82 vs. 63 points) but independent of fracture type. The preoperative ASA score, the Charlson comorbidity index, and the patient age were determined to be decisive for 3-year mortality. CONCLUSION: This case series displayed a high absolute mortality even if the rate was slightly lower compared to previously published data. The rate of secondary dislocations, lack of fracture healing or follow-up operations were also low. The LPF therefore appears to be a suitable treatment for fractures with a stable prosthesis. However, there is a high variability in the clinical outcome regardless of the type of fracture and significantly increased mortality rates in previously ill patients.

Cancellous allogenic and autologous bone grafting ensure comparable tunnel filling results in two-staged revision ACL surgery.

OBJECTIVES: Patients with recurrent instability after anterior cruciate ligament (ACL) reconstruction often present with enlarged or misplaced tunnels and bone grafting is required prior to the actual revision reconstruction. Autologous bone grafting features limited quantity and donor site morbidity. These problems may be eliminated utilizing cancellous bone allografts, but their efficiency and reliability have not been investigated systematically. The aim of the present study was to compare tunnel filling rates attained by utilizing either allogenic or autologous cancellous bone grafts. MATERIALS AND METHODS: A total of 103 consecutive patients were enrolled retrospectively. All patients suffered from recurrent instability and underwent either allogenic or autologous cancellous bone grafting. Computed tomography (CT) was carried out before and after the bone grafting procedure. Based on preoperative CT scans, positioning and maximum diameter of the femoral and tibial tunnels were determined. Tunnel filling rates were calculated as a ratio of pre- and postoperative tunnel volumes. Primary outcome was the tibial tunnel filling rate. Femoral filling rates and density of the grafted bone were assessed secondarily. RESULTS: Preoperative CT scans revealed no significant differences between the two groups regarding distribution of misplacement and widening of the femoral or tibial tunnel. Postoperative CT scans were conducted after an interval of 5.2 months. Tunnel filling rates of 74.5% (± 14.3) femoral and 85.3% (± 10.3) tibial were achieved in the allogenic compared to 74.3% (± 15.9) femoral and 84.9% (± 9.4) tibial in the autologous group. With p values of 0.85 at the femur and 0.83 at the tibia, there were no significant differences between the groups. The density of the grafted bone revealed significantly higher values in the allogenic group. CONCLUSIONS: Utilizing cancellous bone allografts in two-staged revision ACL surgery provides for sufficient and reproducible filling of enlarged or misplaced tunnels. The filling rates are comparable to those achieved with autologous bone grafting. Advantages of allografts are the unrestricted quantity and the absence of any harvesting procedure.

[Gluteal compartment syndrome after immobilization following opioid abuse]. / Gluteales Kompartmentsyndrom nach Liegetrauma bei Opiatabusus.

This article reports the case of a 42-year-old male patient, who sustained a gluteal compartment syndrome after drug-induced immobilization with subsequent rhabdomyolysis and sciatic nerve palsy. Unlike compartment syndrome of the forearm or lower leg, this is a rare condition. After immediate surgical decompression and installation of negative pressure wound treatment, hemofiltration in acute renal failure could be averted using forced diuresis. The sensorimotor function of the lower extremity improved already after the first treatment and secondary wound closure was possible after 1 week. The patient was discharged 11 days after admission with complete recovery of sensorimotor and renal functions.

[Tendonitis calcarea of the piriformis muscle in a young amateur athlete]. / Tendinitis calcarea des M. piriformis bei einer jungen Amateursportlerin.

Distinct calcific tendonitis associated with chronic pain refractory to conservative treatment can require operative treatment. Symptomatic calcific tendonitis of the piriform muscle, despite calcific tendonitis of other regions, is an extremely rare diagnosis. We report about a young athlete with persistent gluteal pain despite long-term conservative treatment. MRI scans revealed tendonitis calcarea with surrounding soft tissue inflammation. On open surgical removal of the calcification, pain symptoms were relieved and the patient was able to return to sports.

[Team training and assessment in mixed reality-based simulated operating room : Current state of research in the field of simulation in spine surgery exemplified by the ATMEOS project]. / Teamtraining und Assessment im Mixed-reality-basierten simulierten OP : Aktueller Stand der Forschung im Bereich Simulation in der Wirbelsäulenchirurgie am Beispiel des Projekts ATMEOS.

Surgical simulators are being increasingly used as an attractive alternative to clinical training in addition to conventional animal models and human specimens. Typically, surgical simulation technology is designed for the purpose of teaching technical surgical skills (so-called task trainers). Simulator training in surgery is therefore in general limited to the individual training of the surgeon and disregards the participation of the rest of the surgical team. The objective of the project Assessment and Training of Medical Experts based on Objective Standards (ATMEOS) is to develop an immersive simulated operating room environment that enables the training and assessment of multidisciplinary surgical teams under various conditions. Using a mixed reality approach, a synthetic patient model, real surgical instruments and radiation-free virtual X­ray imaging are combined into a simulation of spinal surgery. In previous research studies, the concept was evaluated in terms of realism, plausibility and immersiveness. In the current research, assessment measurements for technical and non-technical skills are developed and evaluated. The aim is to observe multidisciplinary surgical teams in the simulated operating room during minimally invasive spinal surgery and objectively assess the performance of the individual team members and the entire team. Moreover, the effectiveness of training methods and surgical techniques or success critical factors, e. g. management of crisis situations, can be captured and objectively assessed in the controlled environment.

A new 3D software for analysis and planning of lower limb and patellofemoral alignment: Reliability and accuracy.

BACKGROUND: The new software, mediCAD® 3D Knee Sport (mediCAD Hectec GmbH, Altdorf/Landshut, Germany), promises to combine automated digital 3D bone model generation, 3D analysis of lower limb geometry including analysis of the patellofemoral joint, and osteotomy planning. The aim of this study was to evaluate its reliability and accuracy. METHODS: In this retrospective multi-observer study, three post-mortem CTs were analysed by three observers at three points in time. Reliability was evaluated by calculating the intraclass correlation coefficient (ICC) of interobserver agreement. Accuracy was evaluated using the mean deviation D from the mean and the standard deviation SD from D. RESULTS: Ten of 18 alignment parameters showed excellent, two good and three moderate interobserver agreement. Poor agreement was found for the mechanical medial proximal tibial angle, the trochlear sulcus angle and trochlea depth. Mean interobserver ICC of all parameters ranged from 0.32 to 0.99. Fifteen of 18 parameters showed a low mean deviation D from the mean of < 2 mm / 2°. Three parameters related to the patellofemoral joint showed medium or high D (patella tilt, trochlear sulcus angle, patellar ridge angle). These parameters also showed the highest values for the SD of D. The trochlear sulcus angle was found to be the only parameter with high mean deviation (D ≥ 5 mm/5°) with D being 5.67 ± 3.23°. CONCLUSIONS: The current version of the software achieves good interobserver reliability and accuracy with the exception of a few measurement parameters.

Three-dimensional assessment of patellofemoral anatomy: Reliability and reference ranges.

BACKGROUND: Three-dimensional (3D) imaging and analysis offer new possibilities in preoperative diagnostics and surgical planning. Simultaneous 3D analysis of the joint angles and the patellofemoral anatomy allow for a realistic assessment of bony pathologies in patients with patellofemoral complaints. This study aims to develop a standardized and validated assessment of the 3D patellofemoral morphology and to establish reference ranges. METHODS: Thirteen patellofemoral anatomic landmarks were defined on 3D bone models of the lower limbs based on computer tomography data and evaluated regarding inter- and intra-observer variability. Further, 60 3D models of the lower limbs of young subjects without any previous knee operation/injury were assessed and rescaled reference values for relevant patellofemoral indices were obtained. RESULTS: The mean inter- and intra-observer deviation of all landmarks was below 2.3 mm. The interobserver intraclass correlation coefficient (ICC) was between 0.8 and 1.0 and the intra-observer ICC between 0.68 and 0.99 for all patellofemoral parameters. The calculated reference ranges are: Insall-Salvati index 1.0-1.4; patella tilt 6-18°; patella shift -4 to 3 mm; patella facet angle 118-131°; sulcus angle 141-156°; trochlear depth 3-6 mm; tibial-tuberosity to trochlear groove distance(TT-TG) 2D 14-21 mm; TT-TG 3D 11-18 mm; lateral trochlear inclination 13-23°; trochlear facet angle 43-65°. CONCLUSION: The demonstrated 3D analysis of the patellofemoral anatomy can be performed with high inter- and intra-observer correlation. Applying the obtained reference ranges and using existing 3D assessment tools for lower limb alignment, a preoperative 3D analysis and planning for complex knee procedures now is possible.

Schatzker II tibial plateau fractures: Anatomically precontoured locking compression plates seem to improve radiological and clinical outcomes.

INTRODUCTION: The design of anatomically precontoured locking compression plates (LCP) allows the placement of angular stable screws right underneath the reduced joint surface fragments. To date, there is a lack of evidence supporting the broad utilization of these implants in split depression fractures to the lateral tibial plateau. Thus, aim of the present matched pair retrospective cohort study was to investigate the radiological and clinical outcomes of anatomically precontoured LCP compared to conventional plate and screw osteosynthesis in Schatzker II fractures. MATERIAL AND METHODS: The institutional databank was searched for Schatzker II fractures from 2010 to 2016. Patients that underwent open reduction and internal fixation with anatomically precontoured 3.5 mm LCP or conventional 4.5 mm l-shaped plates and screws were included. CT scans and radiographs were analyzed. Details of the operative procedures and secondary events were collected. A matched pair analyses was conducted in a best fit manner. The primary outcome parameter was the Rasmussen Radiological Score approximately one year postoperatively. Secondary outcome parameters were the medial proximal tibial angle (MPTA), the Rasmussen Clinical Score and the WOMAC Score after a follow up of at least three years. RESULTS: A total of 50 patients was included. Patient age, gender distribution, size and depression depth of the lateral joint surface fragments, frequency of utilizing bone grafts or substitutes and lateral meniscus repair as well as subsequent implant removal were comparable across the groups. Immediately postoperatively, the Rasmussen Radiological Score revealed no differences. After a mean of 64.2 weeks, the radiological outcome was significantly better in the LCP 3.5 group (RRS 8.2 vs. 6.3 points, p<0.001; MPTA 89.5 vs. 92.0°, p = 0.001). After a mean clinical follow-up of 4.5 years, the Rasmussen Clinical Score (22.9 vs. 27.8 points, p<0.001) and the WOMAC score (24.3 vs. 16.0 points, p = 0.04) revealed significantly impaired results in the conventional group. CONCLUSION: Anatomically precontoured LCP prevent the subsidence of the reduced joint surface fragments more sufficiently and allow for improved patient outcomes compared to conventional plates and screws. The utilization of anatomically precontoured LCP should therefore closely be considered for internal fixation of any split depression fractures to the lateral tibial plateau.

Three-dimensional assessment of lower limb alignment: Reference values and sex-related differences.

BACKGROUND: Three-dimensional (3D) preoperative planning and assisted surgery is increasingly popular in deformity surgery and arthroplasty. Reference ranges for 3D lower limb alignment are needed as a prerequisite for standardized analysis of alignment and preoperative planning in 3D, but are not yet established. METHODS: On 60 3D bone models of the lower limbs based on computed tomography data, fifteen parameters per leg were assessed by standardized validated 3D analysis. Distribution parameters and differences between sexes were evaluated. Reference values were generated by adding/subtracting one standard deviation from the mean. RESULTS: Women had a significantly lower mean mechanical lateral distal femoral angle compared with men (86.4 ±â€¯2.1° vs. 87.8 ±â€¯2.0°; P < .05) and significantly lower mean joint line convergence angle (-2.5 ±â€¯1.4° vs. -1.3 ±â€¯1.2; P < .01), but higher mean hip knee ankle angle (178.9 ±â€¯1.9° vs. 177.8 ±â€¯2.3°; P < .05) and mean femoral torsion (18.2 ±â€¯9.5° vs. 13.2 ±â€¯6.4°; P < .05), resulting in a tendency towards valgus alignment and vice versa for men. Differences in mean medial proximal tibial angle were not significant. The mean mechanical axis deviation from the tibial knee joint center was 6.9 ±â€¯7.3 mm medial and 1.4 ±â€¯16.1 mm ventral without significant differences between sexes. CONCLUSIONS: We describe total and sex-related reference ranges for all alignment relevant axes and joint angles of the lower limb. There are sex-related differences in certain alignment parameters, which should be considered in analysis and surgical planning.

Impacted Steel Sleeves for a minimally invasive approach in intramedullary nailing.

A custom-made instrument set of Steel Sleeves was developed to assist the insertion of reamers and intramedullary devices for fixation of long bone fractures or lengthening procedures with intramedullary nails. By use of the Steel Sleeves, migration of the entry point is prevented and protection of the bone and soft tissue at the entry point is guaranteed. In addition, the principle of a closed working channel for trans-articular approaches can be provided. In this article, a description of properties and clinical application of custom-made steel sleeve instrument set is provided.

Intraoperative customization of intramedullary nails - First results.

INTRODUCTION: Intramedullary nailing is a valuable treatment option for many types of fractures. Furthermore nailing is applicable for osteosynthesis following osteotomy in deformity correction. For intraoperative fine-tuning of alignment in intramedullary (IM) nailing procedures, a bending device for customization of IM nails under sterile conditions was developed. We have performed a retrospective clinical study to analyze and describe the technical requirements, indications and limitations for intraoperative customization of IM nails. MATERIALS AND METHODS: In 41 cases of deformity correction with IM nailing, we applied intraoperative sterile bending of IM nails. The patient age ranged from 13 to 64 years. We evaluated the radiological outcome (precision of the intervention) of 31 completed cases, comparing the preoperative planning with the final result on long-standing radiographs (LSR). The diameter of the nails ranged from 8,5mm to 13mm. Cases with fracture or non-union treatment with intraoperative application of the bending device were excluded and analyzed separately. RESULTS: All removed implants were examined - none of them showed any signs of material fatigue. The amount of intraoperative bending of the nails was 1° to 12°. A high level of precision was achieved, with a median postoperative axis deviation to the preoperative planning of 3,5mm. In a polio patient with limited bone quality, the implant removal caused an undisplaced cortical crack. There were no other complications. There was uneventful and fast bone healing in all patients. CONCLUSIONS: Intraoperative customization of intramedullary nails is a valuable technique for precise alignment control with IM nailing. With this technique, the benefits of IM nailing can be used for a wide range of indications, including deformity correction. The sterile bending device is safe and easy to handle. It is strong enough to bend all commercially available IM nails. Monofocal or linear bending in multiple planes is possible. However, when defining the site of bending, one must consider the removal of the implant in the future.

Three-dimensional assessment of lower limb alignment: Accuracy and reliability.

INTRODUCTION: Three-dimensional (3D) surgical planning and patient-specific implants are becoming increasingly popular in orthopedics and trauma surgery. In contrast to the established and standardized alignment assessment on two-dimensional (2D) long standing radiographs (LSRs) there is neither a standardized nor a validated protocol for the analysis of 3D bone models of the lower limb. This study aimed to create a prerequisite for pre-operative planning. METHODS: According to 2D analysis and after meticulous research, 24 landmarks were defined on 3D bone models obtained from computed axial tomography (CT) scans for a 3D alignment assessment. Three observers with different experience levels performed the test three different times on three specimens. Intraobserver and interobserver variability of the landmarks and the intraclass correlation coefficient (ICC) of the resulting axes and joint angles were evaluated. RESULTS: Overall, the intraobserver and interobserver variability was low, with a mean deviation <5 mm for all landmarks. The ICC of all joint angles and axis deviations was >0.8, except for tibial torsion (ICC = 0.69). All knee joint angles showed excellent ICC (>0.95). CONCLUSIONS: Using the defined landmarks, a standardized 3D alignment assessment with low intraobserver and interobserver variability and high ICC values for the knee joint angles can be performed regardless of examiner's experience. The described method serves as a reliable standardized protocol for a 3D malalignment test of the lower limb. Three-dimensional pre-operative analysis might enhance understanding of deformities and lead to a new focus in surgical planning.

Outcomes of revision anterior cruciate ligament reconstruction secondary to reamer-irrigator-aspirator harvested bone grafting.

INTRODUCTION: Patients with widened or misplaced tunnels may require bone grafting prior to revision anterior cruciate ligament (ACL) reconstruction. Utilising reamer-irrigator-aspirator (RIA) harvested bone from the femur showed promising filling rates. Nevertheless, the procedure has neither been validated in a larger population nor been assessed with regards to radiological and clinical outcome of the subsequently conducted revision ACL reconstruction. Therefore, the aim of this study was to evaluate tunnel filling rates, positioning of the revision tunnels and outcome parameters of such two-staged revision ACL reconstructions. MATERIAL AND METHODS: A total of 15 consecutive patients were prospectively enrolled in this case series. CT scans were analysed before and after autologous RIA harvested bone grafting. Tunnel volumes and filling rates were calculated based on manual segmentation of axial CT scans. Revision ACL reconstruction was carried out after a mean interval of 6.2 months (±3.7) and positioning of the revision tunnels was assessed by plane radiographs. The mean follow-up was 19.8 months (±8.4) for objective evaluation and 37.1 months (±15.4) for patient reported outcomes. The clinical outcome was assessed by the quantification of the anterior tibial translation, the IKDC objective score, the Tegner activity scale and the Lysholm score. RESULTS: Initial CT scans revealed mean tunnel volumes of 3.8cm3 (±2.7) femoral and 6.1cm3 (±2.4) tibial. Filling rates of 76.1% (±12.4) femoral and 87.4% (±5.9) tibial were achieved. Postoperative radiographs revealed significantly improved tunnel positioning with anatomical placement in all but one case at the femur and in all cases at the tibia. At follow up, patients showed significantly improved anterior tibial translations with residual side-to-side differences of 1.7 mm (±0.8) and significantly improved IKDC objective scores. Furthermore, significantly higher values were achieved on the Tegner activity scale (5.3 ± 1.4 vs. 2.8 ± 0.5) and the Lysholm score (85.4 ± 7.9 vs. 62.5 ± 10.5) compared to the preoperative status. CONCLUSION: Autologous RIA harvested bone grafting ensures sufficient bone stock consolidation allowing for anatomical tunnel placement of the subsequently conducted revision ACL reconstruction. The two-staged procedure reliably restores stability and provides satisfying subjective and objective outcomes. Thus, RIA harvested bone grafting is an eligible alternative to autologous iliac crest or allogenic bone grafting.