Reconstruction of an Extensive Segmental Radial Shaft Bone Defect by Vascularized 3D-Printed Graft Cage

We report here a 46-year-old male patient with a 14 cm segmental bone defect of the radial shaft after third degree open infected fracture caused by a shrapnel injury. The patient underwent fixed-angle plate osteosynthesis and bone reconstruction of the radial shaft by a vascularized 3D-printed graft cage, including plastic coverage with a latissimus dorsi flap and an additional central vascular pedicle. Bony reconstruction of segmental defects still represents a major challenge in musculo-skeletal surgery. Thereby, 3D-printed scaffolds or graft cages display a new treatment option for bone restoration. As missing vascularization sets the limits for the treatment of large-volume bone defects by 3D-printed scaffolds, in the present case, we firstly describe the reconstruction of an extensive radial shaft bone defect by using a graft cage with additional vascularization.

[Limb-sparing resection of axillary soft tissue sarcomas]

OBJECTIVE

For patients with soft tissue sarcoma, surgical resection is a key element of curative therapy. Surgery is performed as a wide resection with microscopically negative margins (R0 resection) and as limb-sparing procedure whenever possible to preserve maximum function.

INDICATIONS

Soft tissue sarcoma, metastases.

CONTRAINDICATIONS

Extensive disease with major neurovascular involvement, placement of biopsy tract necessitates extensive resection, palliative care.

SURGICAL TECHNIQUE

Extended deltopectoral approach. Release of pectoralis major and minor tendons. Vascular and neurologic exploration, identification of the axillary vessels and brachial plexus, placing of loops around major structures. Mobilization of these structures to achieve adequate exposure. Clipping of vessels entering the tumor. Tumor resection, suture marking for histological analysis. Soft tissue reconstruction by transosseous reinsertion of the pectoralis minor to the coracoid process. Drill channel placement, transosseous refixation of the pectoralis major to the humerus.

POSTOPERATIVE MANAGEMENT

Shoulder abduction brace for 6 weeks, passive mobilization for 6-12 weeks followed by active mobilization. Compression sleeve. Oncological follow-up.

RESULTS

Between 2017 and 2022, wide resection was performed in 6 consecutive cases including 4 primary soft tissue sarcomas and 2 metastases. Primary R0 resection was achieved in 100%. Mean follow-up was 22.5 months (3-60 months). There were no local recurrences. Mean active shoulder abduction was 135.0 ± 41.4° (90-180°). Neurological deficits were not observed. Mean subjective shoulder function was 80.0 ± 21.0% (50-100%). The mean Musculoskeletal Tumor Society (MSTS) score was 89.5% (32-100%), indicating good functional outcome in the study cohort.

[Biological reconstruction of large bone defects : Masquelet technique and new procedures]

Extensive diaphyseal and metaphyseal bone defects continue to pose a major challenge for orthopedic trauma surgeons. Various treatment options have been described for the biological reconstruction of these defects. The most frequently used methods are bone segment transport, the Masquelet technique and 3D printed scaffolds. As far as the Masquelet technique is concerned, in the first stage spacers, such as polymethyl methacrylate (PMMA), calcium sulfate or polypropylene are inserted into the bone defects to induce a foreign body membrane. In the second stage the bone defect surrounded by the induced membrane is filled with autologous cancellous bone. The time interval between the first and second interventions is usually 4-8 weeks whereby the induced membranes do not lose their bioactivity even with a latency period longer than 8 weeks. Three-dimensional printed scaffolds are increasingly used but large clinical studies are lacking in order to show the exact role of this procedure in the reconstruction of bone defects.

Posterior acetabular wall morphology is an independent risk factor that affects the occurrence of acetabular wall fracture in patients with traumatic, posterior hip dislocation

PURPOSE

Smaller posterior acetabular walls have been shown to independently influence the risk for bipolar hip dislocation. We asked whether differences would also be observed in patients with traumatic posterior hip dislocation with and without posterior wall fractures.

METHODS

Between 2012 and 2020 we observed 67 traumatic posterior hip dislocations. Of these, 43 traumatic posterior hip dislocations in 41 patients met the inclusion criteria. Eighteen dislocations were excluded with an acetabular fracture other than posterior wall fracture and six dislocations had insufficient computed tomography (CT) data. The mean age was 41 ± 11 years, 32 males and nine females. We observed 26 traumatic hip dislocations with posterior wall fractures and 17 without. All patients underwent polytrauma CT scans and postoperative/postinterventional pelvic CT scans. On axial CT-scans, posterior wall determining angles were measured.

RESULTS

Patients with posterior wall fractures were not significantly older than patients without posterior wall fractures (42 ± 12 vs. 38 ± 10 years; p = 0.17). Patients without posterior wall fractures had significantly smaller posterior acetabular sector angles (84° ± 10°) than did patients with posterior wall fractures (105° ± 12°) (p < 0.01; OR 1.178). Likewise, the posterior wall angle was significantly smaller in patients without posterior wall fracture (62° ± 9°) than in those with posterior wall fractures (71° ± 8°) (p < 0.01; OR 1.141).

CONCLUSION

Both posterior acetabular sector angle and posterior wall angle are independent factors determining the posterior wall fracture morphology in patients with traumatic posterior hip dislocation. Age and the observed trauma mechanism did not differentiate between traumatic posterior hip dislocations with and without posterior wall fractures.

Validation of direct CT measurement of malrotation in femoral neck fractures: A bone model study

BACKGROUND

While postoperative malrotation in the subtrochanteric region is a well-known problem, malrotation after osteosynthesis in proximal femoral fractures has not been extensively studied. In this context, many methods for perioperatively assessment of femoral torsion have been described, but none of them is applicable in the basicervical region of the proximal femur. As an important difference in femoral neck fractures, the discontinuous neck fails to serve as a significant "pointer" for measurements and malfunctions to be placed in relation to the condylar plane. Considering postoperative maltorsion at any location as a substantial negative effect on patients' outcome and functional expectations, precise and patient-friendly rotation measurement standards in femoral neck fractures are desired in clinical practice. Recently, a novel computed tomography (CT) based geometric technique was described named "direct measurement" with promising results covering this diagnostic disparity, but still requires validation. Thus, we aimed to validate the previously described technique using a controlled range of displacement in a femoral neck fracture Sawbone® model.

METHODS AND FINDINGS

A goniometer was designed to set retro- and anteversion of the proximal femur in a reproducible manner. Prospectively, all femurs underwent a CT scan and were measured 3D for displacement. The interclass correlation between the CT measurements and the goniometer measurements was calculated and was found to be very high (1.00, 95% confidence interval: 0.99-1.00; p < 0.001). For the mean of all measurements, the Pearson's correlation was 1.00 (p < 0.001). No significant differences in the measurements of both investigators were observed, with 20° of retroversion not significant (-1.20 ± 1.71; 95% confidence interval: -2.43-0.03; p = 0.054).

CONCLUSION

This CT-based 3D measurement technique may allow for perioperative malrotation assessment in basicervical femoral neck fractures and appears to be feasible in femoral neck fractures when it comes to rare cases of osteosynthesis. Further investigations are still needed to define the thresholds of malrotation provoking functional impairment after osteosynthesis in basicervical femoral neck fractures.

[Management of fracture-related infections]

Fracture-related infections (FRI) are a major challenge in orthopedic trauma surgery. The problems in the treatment of such infections are manifold. Especially in cases with insufficient fracture consolidation the treatment not only focusses on the eradication of the infection but also on the restoration of the osseous continuity. The extent of the accompanying soft tissue damage is of particular importance as reduced vascularization leads to impairments in fracture healing. Although acute infections are frequently easy to recognize, the symptoms of chronic infections can be unspecific and evade the diagnostic procedures. This fact makes the treatment of such infections complicated and sometimes necessitates an interdisciplinary approach. For this reason, the Fracture-related Infection Consensus Group developed an algorithm, which was first published in 2017 and revised in 2018 and 2020. The FRIs are biofilm-associated infections, so that the current guidelines follow the previously established treatment algorithms for periprosthetic infections. Despite the analogies to periprosthetic infections there are also differences in the treatment as the aspects of fracture healing and bone defect restoration represent determining factors in the treatment of FRI. This article presents the special features of FRI and the classification and guidelines for the treatment are discussed.

Patella baja after intramedullary nailing of tibial fractures, using an infrapatellar/transtendinous approach, predicts worse patient reported outcome

Purpose

After intramedullary nailing of tibial shaft fractures using an infrapatellar/transtendinous approach, several patients suffer anterior knee pain. We suspect that the approach is associated with soft tissue scars and the development of a postoperative patella baja. The goal of the study is to investigate whether the development of patella baja is associated with worse subjective outcomes.

Methods

We retrospectively analyzed all patients in our orthopedic trauma department between 2011 and 2020 who underwent tibial fracture fixation via intramedullary nailing via an infrapatellar/transtendinous approach. Pre- and postoperative lateral knee x-rays were evaluated by measurement of the Insall-Salvati Index, and nail tip position. All patients were asked to answer the self-assessment Kujala questionnaire and Lysholm questionnaire.

Results

We included 78 patients (age: 44 ± 18 years) with a minimum follow-up of 12 months. Mean follow up was 59 ± 25 months. We included 50 male and 28 female patients. Patella baja detected by Insall-Salvati Index could be observed in 8 (10.3%) patients. Patients with patella baja showed significant worse function measured by the Kujala score 54 ± 18 vs. 80 ± 14 (p < 0.01). Likewise, Lysholm score did show significant differences between both groups (60 ± 24 vs. 86 ± 11; p < 0.01). Nail tip position was not associated with worse subjective function.

Conclusions

Patella baja in patients after tibial intramedullary nailing via an infrapatellar/transtendinous approach, is associated with worse subjective function and increased pain.

Possible Correlation Between Kyphosis of Lumbar Osteoporosis Fractures and the Spinal Signal Intensity Ratio (SSIR)

BACKGROUND

The aim of this study was to examine the correlation between the risk of increasing kyphosis as well as collapse of the osteoporotic vertebral body fractures and the intensity of the bone edema in magnetic resonance imaging (MRI) scans. Inclusion criteria included the following: age >18 years and osteoporotic vertebral body fracture grade I-IV according to OF classification. Exclusion criteria included the following: other pathological fractures due to primary tumors or metastasis, OF grade V fractures, and AO type B or C fractures.

METHODS

This was a retrospective study from pseudonymized data of a tertiary spine center. No additional imaging were performed. Measurements of bisegmental kyphosis angle of the fracture for involvement of both endplates and monosegmental angle for involvement of 1 endplate, as well as vertebral body height loss in initial radiographs and at follow-ups after 3 and 6 months have been performed. Also, the initial signal intensity of the vertebral body edema was measured using integrated tool of the DICOM viewer (Impax V6.5 Agfa, Brentford, UK) in addition to the signal intensity of the cerebrospinal fluid (CSF) as reference for T1, T2, and separate target illumination radar (STIR) sequences of the MRI scans. A quotient from the signal intensity of the vertebral body edema and the reference (CSF) has been generated. Patients have been divided to 4 groups according to the ratio (<1, 1-2, 2-3, >3) and compared in regards to the results of the degree of kyphosis and vertebral collapse at follow-ups and final examination. The statistical analysis was performed using linear regression using statistic software SPSS version 26.

RESULTS AND CONCLUSIONS

Forty-four patients have been included: 9 males and 35 females with an average age of 71.5 years. The analysis showed a significant correlation between the increasing kyphosis at follow-ups and the quotient of the signal intensity for STIR and T2 weighing with P = .002 (SD ±2.664) for STIR and P = .001 (SD ±1.616) for T2 sequences. Furthermore, there was only a correlation between the intensity ratio and kyphosis for STIR weighting at last examination (P = .017; SD ±1.360). There was no correlation between the height loss and the signal intensity.

LEVEL OF EVIDENCE

Level 2.

Direct measurement of malrotation of traumatic femoral neck fractures after osteosynthesis: Introduction of a novel method and interrater reliability

Background

In elderly patients, displaced femoral neck fractures are mostly treated by arthroplasty; however for younger patients (<50 years), open reduction and internal fixation is considered the gold standard approach. Despite there being no consensus on the specific procedure, everyday clinical practice in a level I trauma center has shown that postoperative maltorsion after internal fixation of femoral neck fractures can have a significantly worse impact on mobilization and outcome. Different methods for measurement of malrotations are reported in literature. However, any reported method for the assessment of a shaft malrotation in the femur does not work here. In femoral neck fractures, the pointer function of the femoral neck, which is absolutely essential for these techniques, is lost and cannot be set in relation to the condylar plane. These circumstances are not addressed in literature thus far. Therefore, we propose here a novel method to fill this diagnostic gap.

Methods and findings

Three investigators (1 orthopaedic surgeons and 2 radiologists) measured the torsion of 20 legs on 10 patients using the Jarret method and a new geometric technique. To determine the intraobserver reliability the torsional angles were calculated again after 3 months. We applied a new geometric technique, without the need to include the femoral condyles in the measurement, to directly measure the angulation. For torsional difference, the interrater reliability -ICC (interclass correlation) between all investigators was 0.887 (good) (significance level: 95%CI, 0.668–0.969; p<0.001), by using the method of Jarret et al. and 0.933 (good) for the novel technique (significance level: 95%CI, 0.802–0.982; p<0.001). If the examinations are classified according to the patient side, our data show that for established methods, an ICC between the examiners on the right lower extremity is 0.978 (good) (95%CI, 0.936–0.994; p<0.001) and that on the left extremity is 0.955 (good) (95%CI, 0.867–0.988; p<0.001). Comparing with the new method, the right side assumes an ICC of 0.971 (good) (95%CI, 0.914–0.992; p<0.001), while the left side assumes an ICC of 0.910 (good) (95%CI, 0,736–0.976; p<0.001). When it comes to the intraobserver reliability, the measured cohort shows a significant better ICC for the novel method compared to Jarrett et al, with 0.907 respectively 0.786 for comparison in torsional differences.

Conclusion

The established methods may fail in assessing this special aspect of malrotation after femoral neck fractures. Here, the method presented results in a significant difference between the injured and uninjured side and shows significant differences in results compared to conventional measurement methods. The inter- and intraobserver reliability determined in this study is excellent and even higher in the assessment of torsional differences than the established method. We believe that the measurement method presented in this study is a useful tool to objectify the postoperative deformities in this area and making therapy recommendations in the future.

Comparison of Preoperative Pedicle Screw Measurement Between Computed Tomography and Magnet Resonance Imaging

BACKGROUND

Pedicle screw fixation is commonly used in the treatment of spinal pathologies. While the biomechanical factors that affect bone fixation have been frequently described, questions remain as to which imaging modality is the ideal medium for preoperative planning. Due to its perceived superiority in assessing bony changes, computed tomography (CT) scan is assumed to be the gold standard for preparative planning, and we hypothesize that magnetic resonance imaging (MRI) is sufficiently accurate to predict screw length and diameter compared to CT.

METHODS

We retrospectively measured the length and diameter of vertebral bodies in the lumbar region in both MRI and CT and tested for differences between the modalities as well as for confounding effects of age, sex, and the presence of spondyloarthrosis.

RESULTS

We found a significant difference in pedicle screw length between CT and MRI measurements for both sides. For the left pedicle, the mean difference was 1.89 mm (95% confidence interval [CI] -3.03 to -0.75; P < .002), while for the right pedicle, the mean difference was 2.05 mm (95% CI -3.27 to -0.84; P = .001). We also found a significant difference in diameter measurements between CT and MRI for the left pedicle (0.53 mm; 95% CI 0.13 to 0.93; P = .011) but not for the right pedicle (0.36 mm; 95% CI -0.06 to 0.78; P = .094). We identified no significant effect of sex, age or spondyloarthrosis on the results (P > .05).

CONCLUSIONS

Pedicle screw planning measurements were more accurate using CT images compared to MRI images. CT scan remains the gold standard for pedicle screw planning in trauma surgery. When using MRI images, the surgeon should be aware of the differences in screw length and diameter compared to CT in order to avoid intra- and postoperative risks.

Risk factors for dislocation after bipolar hemiarthroplasty: a retrospective case-control study of patients with CT data

Purpose

Bipolar hemiarthroplasty has been shown to have a lower rate of dislocation than total hip arthroplasty. However, as the influencing risk factors for bipolar hemiarthroplasty dislocation remain unclear, we aimed to analyse patient and surgeon-specific influencing risk factors for bipolar hemiarthroplasty dislocation.

Methods

We retrospectively analysed patients who were operated between 2012 and 2018 and had dislocated bipolar hemiarthroplasty and matched them to patients without a dislocated bipolar hemiarthroplasty, operated between 2018 and 2019. The study was limited to patients who received either a pre- or postoperative pelvic computed tomography. Besides demographic, morphologic, and physiologic data, we analysed duration of surgery; ASA score; Charlson Comorbidity Index; Almelo Hip Fracture Score; Parker Score; and acetabular morphology angles including acetabular anteversion angle, posterior acetabular sector angle, posterior wall angle, and acetabular roofing.

Results

We included nine patients with a dislocated bipolar hemiarthroplasty and 30 with a non-dislocated bipolar hemiarthroplasty. Patient-specific factors prompting a higher risk for dislocated bipolar hemiarthroplasty were longer duration of surgery (min) (115 ± 50 vs. 80 ± 27, p = 0.01); dementia (56% vs. 13%, p < 0.01); smaller posterior acetabular sector angle (°) (96 ± 6 vs. 109 ± 10, p < 0.01); and smaller posterior wall angle (°) (67 ± 6 vs. 77 ± 10, p = 0.02).

Conclusion

Dementia and insufficient posterior wall angle were associated with higher risk of dislocation in bipolar hemiarthroplasty

Reduction of Patella-baja and Pseudo-patella-baja Does Not Improve Range of Motion in Patients After Mega-TKA

BACKGROUND/AIM

Patella baja (PB) and pseudo-patella baja (PPB) have been shown to negatively influence outcomes after total knee arthroplasty. We hypothesized that there is a high incidence of PB and PPB after megaprosthetic total knee arthroplasty (M-TKA), and that this is associated with reduced range of motion.

PATIENTS AND METHODS

We retrospectively analysed all patients in our Orthopaedic Trauma Department after distal femur or proximal tibia replacement. Preoperative and one-year postoperative follow-up included measurement of range of motion and detection of PB and PPB using radiological indices.

RESULTS

We included 44 patients (age: 73±19 years). Preoperative PB detected by ISI could be reduced from 13 (36%) to 11 (25%) (p<0.01). Preoperative vs. postoperative ISI was 0.88±0.23 vs. 1.06±0.45 (p=0.03). PPB was observed preoperatively in 23 (63%) patients vs. 24 (54%) postoperatively. Preoperative vs. postoperative CDI was 0.70±0.24 vs. 0.95±0.43 (p=0.002). Preoperative flexion was 91°±30° vs. 85°±24° postoperatively (p>0.05).

CONCLUSION

Both PB and PPB are frequently observed after M-TKA. A reduction in PB and PPB alone does not improve postoperative range of motion.

An accuracy evaluation of clinical, arthrometric, and stress-sonographic acute ankle instability examinations

BACKGROUND

Ankle sprain injuries, often due to lateral ligamentous injury, are the most common sports traumatology conditions. Correct diagnoses require an understanding of the assessment tools with a high degree of diagnostic accuracy. Obviously, there are still no clear consensuses or standard methods to differentiate between a ligament tear and an ankle sprain. In addition to clinical assessments, stress sonography, arthrometer and other methods are often performed simultaneously. These methods are often costly, however, and their accuracy is controversial. The aim of this study was to investigate three different measurement tools that can be used after a lateral ligament lesion of the ankle with injury of the anterior talofibular ligament to determine their diagnostic accuracy.

METHODS

Thirty patients were recruited for this study. The mean patient age was 35±14 years. There were 15 patients with a ligamentous rupture and 15 patients with an ankle sprain. We quantified two devices and one clinical assessment by which we calculated the sensitivity and specifity: Stress sonography according to Hoffmann, an arthrometer to investigate the 100N talar drawer and maximum manual testing and the clinical assessment of the anterior drawer test. A high resolution sonography was used as the gold standard.

RESULTS

The ultrasound-assisted gadgetry according to Hoffmann, with a 3mm cut-off value, displayed a sensitivity of 0.27 and a specificity of 0.87. Using a 3.95mm cut-off value, the arthrometer displayed a sensitivity of 0.8 and a specificity of 0.4. The clinical investigation sensitivities and specificities were 0.93 and 0.67, respectively.

CONCLUSIONS

Different assessment methods for ankle rupture diagnoses are suggested in the literature; however, these methods lack reliable data to set investigation standards. Clinical examination under adequate analgesia seems to remains the most reliable tool to investigate ligamentous ankle lesions. Further clinical studies with higher case numbers are necessary, however, to evaluate these findings and to measure the reliability.