Radiographic Assessment of Ankle Fracture Displacement: A Validation Study.

BACKGROUND: Ankle fracture displacement is an important outcome in clinical research examining the effectiveness of surgical and rehabilitation interventions. However, the assessment of displacement remains subjective without well-described or validated measurement methods. The aim of this study was to assess inter- and intrarater reliability of ankle fracture displacement radiographic measures and select measurement thresholds that differentiate displaced and acceptably reduced fractures. METHODS: Eight fellowship-trained orthopaedic surgeons evaluated a set of 26 postoperative ankle fracture radiographs on 2 occasions. Surgeons followed standardized instructions for making 5 measurements: coronal displacement (3) talar tilt (1), and sagittal displacement (1). Inter- and intraobserver interclass correlations were determined by random effects regression models. Logistic regression was used to determine the optimal sensitivity and specificity for the measurements with the highest correlation. RESULTS: Three of the 5 measures had excellent interobserver reliability (correlation coefficient > 0.75): (1) coronal plane distance between the lateral border of tibia and lateral border of talus, (2) coronal plane talar tilt, and (3) sagittal plane displacement. The threshold that best discriminated displaced from well-aligned fractures was 2 mm for coronal plane distance (sensitivity 82.1%, specificity 85.4%), 3 degrees for talar tilt (sensitivity 80.4%, specificity 82.2%), and 5 mm for sagittal plane distance (sensitivity 83.9%, specificity 84.9%). CONCLUSION: This study identified 3 reliable measures of ankle fracture displacement and determined optimal thresholds for discriminating between displaced and acceptably reduced fractures. These measurement criteria can be used for the design and conduct of clinical research studying the impact of surgical treatment and rehabilitation interventions.

Initial assessment of treatment of talar posterior process fractures with open reduction and percutaneous fixation.

The purpose of this study was to provide an initial assessment of treatment for talar posterior process fractures using open reduction and internal fixation (ORIF) through posteromedial approach and percutaneous screw fixation. From January 2014 to December 2018, 12 cases with displaced fracture of talar posterior process were treated in our department. The clinical and radiological results were assessed after 4 and 12 months of operation with Visual Analog Scale (VAS) pain and American Orthopedic Foot and Ankle Society (AOFAS) scores. ORIF was performed in four of the cases and percutaneous screw fixation was performed in eight of the cases. The average follow-up period was 13 months. Complications such as wound infection, nerve injury, screw loosening, malunion or nonunion of fracture were absent. For clinical assessment, considerable mprovements were observed for the AOFAS and VAS scores at 4 and 12 months postoperatively for both techniques. There was no significant difference for AOFAS scores and VAS scores between the two techniques (p > 0.05). Both techniques showed good functional outcome and were performed for posterior talar process fracture following the fracture displacement guidelines. Percutaneous screw fixation treatment with computer-assisted three-dimensional evaluation shortened the operation time and reduced incidences of surgical complications.

Three-Dimensional computed tomography tunnel assessment of allograft anatomic reconstruction in chronic ankle instability: 33 cases.

INTRODUCTION: Although clinical results of anatomic reconstruction using allograft are reportedly good, studies on how accurately the tunnel has been made after surgery are very rare. The purpose of this study was to analyze the postoperative locations of the tunnels through 3-dimensional computed tomography (3D-CT) after anatomic ligament reconstruction and to evaluate its clinical results. HYPOTHESIS: We hypothesized that anatomic lateral ligament reconstruction could lead to excellent results in clinical outcomes by repositioning anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) accurately. MATERIALS AND METHODS: Thirty-three special forces of soldiers who were diagnosed as chronic ankle instability (CAI) were included. Visual analogue scale (VAS), American orthopaedic foot and ankle society (AOFAS) ankle-hind foot functional scores, and Tegner activity scale were comparatively analyzed before the surgery and at final follow-up. The locations of the talar, fibular and calcaneal tunnels were evaluated with 3D-CT taken after the surgery. Talar tilt and anterior drawer displacement were measured on stress radiographs. RESULTS: The mean follow-up period was 26.8±3.6 months. The VAS decreased from 6.9±1.6 to 1.7±1.3, AOFAS ankle-hindfoot functional score increased from 61.3±14.8 to 88.7±9.2, and Tegner activity scale improved from 5.3±1.2 to 6.4±1.3 (p<0.001). Talar tunnel for ATFL was located about68% of the way from the lateral talar process, and fibular tunnels for ATFL and CFL were approximately 52% and 20% of the way from the fibular tip. The calcaneus tunnel was approximately 17mm posterosuperior from the peroneal tubercle on 3D-CT. Talar tilt decreased from 15.8±4.8 to 3.9±2.1 degrees (p<0.001). There were excellent inter-observer agreements for CT evaluation (Kappa values were from 0.83 to 0.92). There was no relapse of lateral instability. DISCUSSION: Anatomic reconstruction of the lateral ligaments using allograft and the interference screw for CAI showed good results in postoperative stability and subjective clinical evaluation by repositioning the location of ATFL and CFL accurately on radiological determination. LEVEL OF EVIDENCE: IV, Case-series.

Clinical outcome and T2 assessment following autologous matrix-induced chondrogenesis in osteochondral lesions of the talus.

PURPOSE: Scientific evidence for the treatment of osteochondral lesions (OCLs) of the talus is limited. The aim of this study was an evaluation of the clinical outcome after a one-step autologous subchondral cancellous bone graft and autologous matrix-induced chondrogenesis (AMIC) in medial OCLs of the talus and the assessment of the repair tissue (RT). METHODS: Seventeen patients (eight women, nine men; mean age, 38.8 ± 15.7 years) with an OCL of the medial talus underwent surgery. Clinical and radiological assessment was performed after a mean follow-up of 39.5 ± 18.4 months, including established scoring systems (American Orthopaedic Foot and Ankle Society [AOFAS] Score, Foot Function Index [FFI], visual analogue scale [VAS]), evaluation of Magnetic Resonance Observation of Cartilage Repair Tissue scoring system (MOCART Score) and T2 mapping. RESULTS: Preoperative pain (7.8 ± 2.1) significantly improved to an average of 3.2 ± 2.4 postoperatively. AOFAS Score averaged 82.6 ± 13.4, MOCART Score 52.7 ± 15.9. Mean T2 relaxation time of the RT was 41.6 ± 6.3 ms and showed no significant differences to the surrounding cartilage (mean, 38.8 ± 8.5; p = 0.58). MOCART Score significantly correlated with the AOFAS Score (rho = 0.574, p = 0.040). T2 relaxation time of the RT significantly correlated with the MOCART Score (rho = 0.593, p = 0.033). CONCLUSIONS: The one-step autologous subchondral cancellous bone grafting and AMIC leads to a significant reduction in postoperative pain and satisfying postoperative functional outcome in mid-term follow-up. Magnetic resonance imaging (MRI) assessment demonstrated a good quality of regenerative tissue similar to the MRI ultrastructure of the surrounding cartilage.

Assessment of ankle and hindfoot stability and joint pressures using a human cadaveric model of a large lateral talar process excision: a biomechanical study.

Lateral talar process fragment excision may be followed by hindfoot instability and altered biomechanics. There is controversy regarding the ideal fragment size for internal fixation versus excision and a concern that excision of a large fragment may lead to significant instability. The aim of this study was to assess the effect of a simulated large lateral talar process excision on ankle and subtalar joint stability.A custom-made seesaw rig was designed to apply inversion/eversion stress loading on 7 fresh-frozen human cadaveric lower legs and investigate them in pre-excision, 5 cm and 10 cm lateral talar process fragment excision states. Anteroposterior radiographs were taken to assess ankle and subtalar joint tilt and calculate angular change from neutral hindfoot alignment to 10-kg forced inversion/eversion. Ankle joint pressures and contact areas were measured under 30-kg axial load in neutral hindfoot alignment.In comparison to the pre-excision state, no significantly different mediolateral angular change was observed in the subtalar joint after 5 and 10 cm lateral talar process fragment excision in inversion and eversion. With respect to the ankle joint, 10-cm fragment excision produced significantly bigger inversion tibiotalar tilt compared with the pre-excision state, P = .04. No significant change of the ankle joint pressure and contact area was detected after 5 and 10-cm excision in comparison with the pre-excison state.An excision of up to 10 cm of the lateral talar process does not cause a significant instability at the level of the subtalar joint but might be a destabilizing factor at the ankle joint under inversion stress. The latter could be related to extensive soft tissue dissection required for resection.

The use of a portable CT scanner for the intraoperative assessment of talocalcaneal coalition resections.

BACKGROUND: Intraoperative assessment of talocalcaneal (TC) coalition resection can be challenging, with no reliable plain radiographic view available for evaluation. Therefore, in March of 2011, we began using a CereTom portable CT scanner to assess TC coalition resections intraoperatively. This study evaluates the use of intraoperative CT during surgical resection of TC coalitions. METHODS: Patients who received CT scans before and after TC coalition resection, by a single surgeon, were included. Those treated without (control group, n=12 feet) and with (intraoperative CT group, n=14 feet) intraoperative CT scan were retrospectively compared. Two blinded pediatric orthopaedic surgeons assessed the quality of resection using a side-by-side comparison of preoperative and postoperative CT scans. Each resection was rated as "excellent," "fair," or "poor," and medical records were reviewed to evaluate clinical outcome. RESULTS: Substantial agreement was found between blinded reviewers (κ=0.71, 81% absolute agreement). Quality of resection was improved in the intraoperative CT group, with 57% of patients receiving an excellent rating compared with 25% in the control group. Patients in the intraoperative CT group were 4.0 times more likely to have a complete resection as compared with patients in the control group; however, this was not statistically significant (odds ratio, P>0.05; 95% confidence interval, 0.74-21.5). Intraoperative CT altered surgical decision making in 3 feet (21%) in the intraoperative CT group, leading to further resection and a subsequent excellent postoperative rating in 2 of these patients. There was 1 reoperation in the control group for continued pain and residual coalition identified on postoperative CT scan. In the intraoperative CT group there have been no reoperations for recurrent or residual qcoalition. CONCLUSIONS: This study illustrates that intraoperative CT can alter surgical decision making and may improve the ability to obtain a complete resection in TC coalition surgery. In these technically challenging cases, intraoperative scans give immediate imaging feedback to surgeons, allowing intervention if residual resection is identified. If intraoperative CT scan is available, it should be considered for surgical treatment of TC coalition resections. LEVEL OF EVIDENCE: Level III retrospective case-control study.

Predictive risk assessment for major amputation after tibiotalocalcaneal arthrodesis.

BACKGROUND: Tibiotalocalcaneal (TTC) arthrodesis using a nail has been shown to be an effective salvage technique; however, there is a risk of major amputation. A better understanding of the relative risk of amputation after TTC fusion and the factors that influence this could help the preoperative consultation and guide discussion on the economics of limb salvage. METHODS: One hundred seventy-nine limbs were treated with TTC fusion with an intramedullary nail. A comprehensive chart and radiographic review was pulled from our intramedullary nail database. Patients were divided into those who went on to eventual amputation and those with successful salvage of their limb. Variables from the database were used to build a statistical model with a biostatistician. Final results were presented, and a formula to determine probability of amputation was created. RESULTS: There were 21 limbs that were eventually treated with major amputation. This represents an overall salvage rate of 88.2% (158/179 patients). Age was a factor in amputation risk, and the highest risk factor for amputation was diabetes with an odds ratio of 7.01 and 95% confidence, P = .0019. The odds of amputation were 6.2 times and 3 times greater for patients undergoing revisions and those with preoperative ulcers, respectively. The probability of amputation could be found preoperatively by using the derived equation: e(x) /(1 + e(x) ) where x is a factor of age, diabetes, revision, and ulceration. CONCLUSION: TTC arthrodesis with a retrograde intramedullary nail has a high rate of limb salvage across a wide range of indications and medical comorbidities. In this patient cohort, diabetes was the most notable risk for amputation, followed by revision surgery, preoperative ulceration, and age. A model has been built to help predict the risk of amputation. LEVEL OF EVIDENCE: Level II, prognostic.

[Navigated Iso-C(3D)-based drilling of a osteochondral lesion of the talus]. / Navigierte Iso-C(3D)-basierte Anbohrung einer osteochondralen Läsion des Talus.

Retrograde drilling of osteochondral lesions has obtained acceptable results in the initial stage. Intraoperatively not all lesions are accessible with the arthroscopic technique, despite being readily identifiable with modern imaging preoperatively. As an alternative, open surgical treatment is recommended to achieve good results. The use of computer-assisted navigated retrograde drilling of osteochondral lesions has been described with promising results as a new technique. Computed tomography (CT)- and fluoroscopy-based navigation systems in current use are limited in their flexibility. The drawbacks of fluoroscopy are lack of three-dimensional imaging intraoperatively. CT-based navigation still requires intraoperative cumbersome registration, extra preoperative planning, and imaging with further technical resources. In the current case report, we describe a patient with an osteochondral lesion of the posteromedial talus. In addition to the current method of arthroscopic evaluation and treatment, we also introduce an alternative technique of using Iso-C(3D)-based navigation-assisted retrograde drilling of the lesion. The advantages of this technique are an actual intraoperative three-dimensional imaging for the use of navigation without the need for anatomical registration and an immediate postoperative control of surgical treatment. The results of this case report demonstrate accurately navigated drilling with the described system. The accuracy was confirmed with immediate intraoperative Iso-C(3D) and postoperative CT scans. Our results indicate that the use of an Iso-C(3D) navigation system is a possible alternative to arthroscopic or open drilling for osteochondral lesions of the talus. To provide further evidence for the use of Iso-C (3D)-based drilling, current studies will start at our institution.

Functional, radiographic, and histologic assessment of healing of autogenous osteochondral grafts and full-thickness cartilage defects in the talus of dogs.

A circular (5.5 mm diameter) full-thickness cartilage defect was created on the medial ridge of the talus in 12 skeletally mature dogs. In 6 dogs, the articular surface of the lesion was repaired, using an osteochondral graft obtained from the ipsilateral manus. The graft (digit I, first phalanx, distal articular surface and diaphysis) was contoured to obtain a press fit in the drilled talar recipient site. In 6 dogs, the lesion was not treated and healed by fibrous tissue replacement. Functional assessment (lameness, hock range of motion, joint stability, joint crepitus, and mid-femoral muscle circumference) was completed before surgery and at postoperative weeks 2 through 20. Radiographic assessment (periarticular soft tissue width, joint space width, osteophyte formation, and graft incorporation) was completed before surgery and at postoperative weeks 0, 6, 12, and 20. To facilitate histologic assessment, tissues were stained with toluidine blue and H&E. Histologic assessment of the articular surface on the surgically treated talus, ipsilateral tibia, and contralateral talus was completed, using a modification of the Mankin grading system. Subchondral bone was examined to assess graft viability and incorporation. Analysis of the ordinal data was completed, using a Mann-Whitney rank sum test. All dogs were fully weight bearing by postoperative week 7. Dogs without grafts had significantly (P = 0.036) better clinical function at postoperative week 6. Significant difference in functional assessment was not evident at postoperative week 20. Immediate postoperative radiographic assessment revealed significant (P = 0.005) difference between nongrafted and grafted groups. Significant difference was not observed at postoperative week 6, 12, or 20. All grafts appeared radiographically incorporated by postoperative week 12. All grafts restored joint surface congruity, whereas 3 of 6 nongrafted lesions had poor articular congruity. Of 6 grafts, 4 partially retained normal hyaline cartilage, resulting in significantly (P = 0.014) lower Mankin grades. Significant histologic differences between groups were not apparent when the apposing tibia and control talus were examined. Talar reconstruction by use of a phalangeal osteochondral graft is a viable surgical procedure. These data indicate that normal articular and subchondral architecture are more closely approximated by osteochondral reconstruction than by fibrous tissue repair.

Lateral talocalcaneal angle in assessment of subtalar valgus: follow-up of seventy Grice-Green arthrodeses.

To determine whether definitive radiographic criteria could be elucidated for the Grice-Green extra-articular subtalar arthrodesis, all 70 cases performed at the Shriner's Hospital for Crippled Children, Erie, Pennsylvania, from 1972 to 1980 were reviewed. Patients were followed both clinically and radiographically an average of 4 years and 11 months. Major conclusions were as follows: 1) the standing lateral talocalcaneal angle is the most reliable measurement for operative selection and assessment of postoperative success; and 2) by using strict operative techniques and proper patient selection, a 90% success rate can be expected.