Quantification of posterior ankle exposure through an achilles tendon-splitting versus posterolateral approach

Three-dimensional Mapping Analysis of Talus Fractures and Demonstration of Different Surgical Approaches for Talus Fractures

OBJECTIVE

The talus is an important component in the ankle, and its treatment after injury is crucial. However, complications and adverse events due to incomplete traditional classifications may still occur, and these classifications fail to analyze the patterns and distribution of fractures from a three-dimensional perspective. Therefore, in this study, we aimed to analyze the location and distribution of fracture lines in different types of talus fractures using three-dimensional (3D) and heat mapping techniques. Additionally, we aimed to determine the surface area of the talus that can be utilized for different approaches of internal fixation, aiding in the planning of surgical procedures.

METHODS

We retrospectively analyzed data from CT scans from 126 patients diagnosed with talus fractures at our two hospitals. We extracted the CT data of a healthy adult and created a standard talus model. We performed 3D reconstruction using patients' CT images and superimposed the fracture model onto the standard model for drawing fracture lines. Subsequently, we converted the fracture lines into a heat map for visualization. Additionally, we measured 20 specimens to determine the boundary for various ligaments attached to the talus. We determined the surface area of the talus available for different surgical approaches by integrating the boundary data with previously reported data on area of exposure.

RESULTS

Without considering the displacement distance of the fracture, fracture types were classified as follows, by combining Hawkins and Sneppen classifications: talar neck, 41.3%; posterior talar tubercle, 22.2%; body for the talus and comminuted, 17.5%; lateral talar tubercle, 11.9%; and talar head, 7.1%. We established fracture line and heat maps using this classification. Additionally, we demonstrated the available area for anteromedial, anterolateral, posteromedial, posterolateral, and medial malleolus osteotomy and Chaput osteotomy approaches.

CONCLUSION

Fracture line and heat map analyses can aid surgeons in planning a single or combined surgical approach for the reduction and internal fixation of talus fractures. Demonstrating the different surgical approaches can help surgeons choose the most effective technique for individual cases.

Comparison of different fibula procedures in tibiotalocalcaneal arthrodesis with a retrograde intramedullary nail: a mid-term retrospective study

BACKGROUND

Tibiotalocalcaneal (TTC) arthrodesis with a retrograde intramedullary nail for severe tibiotalar and talocalcaneal arthritis has a high fusion rate; however, no studies have focused on how to handle the fibula intraoperatively to achieve better results. This study aimed to compare the efficacies of various fibular procedures.

METHODS

We retrospectively reviewed the cases of severe tibiotalar and talocalcaneal arthritis in adults treated with TTC arthrodesis using a retrograde intramedullary nail between January 2012 and July 2017. The patients were divided into three groups according to different fibular procedures: Fibular osteotomy (FO), fibular strut (FS), and fibular preservation (FP). Functional outcomes and pain were assessed using the American Orthopedic Foot and Ankle Society (AOFAS) ankle and hindfoot score and visual analog scales (VAS), respectively. The operation time, fusion time, radiographic evaluation, and complications were also recorded.

RESULTS

Fifty-eight patients with an average age of 53.2 (range, 32-69) years were enrolled in the final analysis. The numbers of patients enrolled in the three groups were 21, 19, and 18 in the FO, FS, and FP groups, respectively. The mean postoperative follow-up time was 66.0 (range, 60-78) months. All groups showed a high fusion rate (90.5% for FO, 94.7% for FS, and 94.4% for FP) and significant improvement in AOFAS ankle and hindfoot scores and VAS scores at the latest follow-up. There were no significant differences in these parameters among the three groups. The mean operation time of FS (131.3 ± 17.1 min) was longer than that of FO (119.3 ± 11.7 min) and FS (112.2 ± 12.6 min), but the fusion time was shorter (15.1 ± 2.8 weeks for FS, 17.2 ± 1.9 weeks for FO, and 16.8 ± 1.9 weeks for FP). Statistically significant differences were observed in these parameters.

CONCLUSIONS

TTC arthrodesis using a retrograde intramedullary nail is an effective procedure with a high rate of fusion to treat severe tibiotalar and talocalcaneal arthritis in adults; however, FSs can shorten fusion time when compared with FO and FP.

LEVEL OF CLINICAL EVIDENCE

Level 3.

The Trans-Achilles Approach for Plate Supplementation of Ankle Arthrodesis With an Existing Hindfoot Fusion Nail: A Case Report

Tibiotalar arthrodesis revision surgeries are not uncommon. Several approaches have been described in the literature for ankle arthrodesis nonunions. In this article, we describe the posterior trans-Achilles approach, which ensures adequate surgical exposure while minimizing damage to the surrounding soft tissues. It provides a convenient method for utilizing bone grafts or substitutes and allows for the advantageous application of posterior plating. The possible complications of this approach are delayed wound healing, wound infection, injury to the sural nerve, and the potential need for a skin graft. Despite the advantages of this approach, infection, delayed union, and nonunion risks remain high in this patient population. Finally, the trans-Achilles approach is valid for complex ankle procedures, especially in revisions with compromised ankle soft tissue envelopes.

Plate Fixation in Midfoot and Ankle Charcot Neuroarthropathy

Surgical reconstruction of Charcot arthropathy in the foot and ankle is extremely difficult. The fundamentals of reconstruction are necessary to provide adequate outcome. Removing and resecting the diseased bone is needed along with good anatomic alignment and rigid fixation. This reconstructive surgery is not only difficult from medical management point of view but also involves patient compliance and good technical components of the surgery from the surgeon. The surgeon must have skills with internal and external fixation, a good understanding of lower extremity vascular disease, and a good understanding of infectious disease and plastic surgical techniques of the lower extremity.

Talar Dome Access Through Posteromedial Surgical Intervals for Fracture Care

BACKGROUND

Posterior talar body fractures are rare injuries without a consensus surgical approach. This study evaluates the accessible area of the talar dome through 2 posteromedial approach intervals (posteromedial [PM] and modified posteromedial [mPM]) both with and without distraction.

METHODS

Ten male cadaveric legs (5 matched pairs) were included. A PM approach, between flexor hallucis longus (FHL) and the tibial neurovascular bundle, and an mPM approach, between FHL and Achilles tendon, was performed on each pair. In total, 4 mm of distraction across the tibiotalar joint was applied with the foot held in neutral position. Accessible dome surface area (DSA) was outlined by drilling with a 1.6-mm Kirschner wire with and without distraction. Specimens were explanted and analyzed by micro-computed tomography with 3-dimensional reconstruction. Primary outcomes were total accessible DSA and sagittal plane access at predetermined intervals.

RESULTS

The PM approach allowed access to 19.1% of the talar DSA without distraction and 33.1% of the talar dome with distraction (P < .001). The mPM approach provided access to 20.4% and 35.6% of the talar DSA without and with distraction (P < .001). Both approaches demonstrated similar sagittal plane access at all intervals except the lateral border of the talus, where the mPM approach provided greater access both without distraction (20.5% vs 4.38%, P = .002) and with distraction (34.3% vs 17.8%, P = .02).

CONCLUSION

The mPM approach, using an interval between FHL and Achilles tendon, provides similar access to the posterior surface of talar dome and better sagittal plane access to the most lateral portion of the dome. The mPM interval provides the advantage of avoiding direct dissection of the tibial nerve or posterior tibial artery. Using an external fixator for distraction can improve talar dome visualization substantially.

LEVEL OF EVIDENCE

Level V, Cadaveric Study.

Does a Medial Malleolar Osteotomy or Posteromedial Approach Provide Greater Surgical Visualization for the Treatment of Talar Body Fractures?

BACKGROUND

Surgical management of talar body fractures is influenced by soft-tissue condition and fracture pattern. Two common surgical approaches for the treatment of talar body fractures are the medial malleolar osteotomy (MMO) and the posteromedial approach (PMA). The purpose of this study was to compare the observable talar body surface area with the MMO and the PMA. We hypothesized that visualization following a PMA improves with distraction and distraction with a gastrocnemius recession.

METHODS

Five pairs of cadaver limbs were used. Each pair of specimens underwent both approaches to act as an internal control. The laterality of the PMA was determined by randomization, and the MMO was performed on the contralateral ankle. The PMA was performed to visualize the talus, and the talar surface area was recorded using a handheld 3D surface scanner. A distractor was then placed across the joint, and the surface area was remeasured. Finally, a gastrocnemius recession was performed, and the measured surface area under the distraction was recorded. The MMO was performed in standard fashion using fluoroscopy, and the observable talar surface area was recorded. Scans were performed twice for each approach, and the surface areas were averaged. The talus was excised and scanned after each approach in order to compare the visualized surface area with the total surface area of the native talus.

RESULTS

The MMO and the PMA exposed a mean of 11.2 and 6.7 cm2, respectively, of the talar surface. Visualization with the PMA was improved with distraction, revealing 8.3 cm2 of the talus (p = 0.01 when compared with an isolated PMA). A PMA with distraction and gastrocnemius recession exposed 9.9 cm2 of the talar dome and body. There was no significant difference in exposure between the MMO and the PMA with distraction and gastrocnemius recession (p = 0.32).

CONCLUSIONS

The MMO and the PMA both afford excellent visualization for reduction and fixation of talar body fractures. Visualization using the PMA is improved with distraction and distraction with a gastrocnemius recession. The results of this study may assist surgeons in selecting the optimal approach for surgical repair of talar body fractures.

Mapping of Posterior Talar Dome Access Through Posteromedial Versus Posterolateral Approaches

OBJECTIVE

To evaluate the accessible area of the talar dome through 2 standard posterior approaches [posteromedial (PM) and posterolateral (PL)] with and without distraction.

METHODS

A standard PM or PL approach was performed with and without external fixator distraction on 12 through-knee cadaveric legs (6 matched pairs). The accessible area of the talar dome was outlined and imaged in a microcomputed tomography scanner to achieve 3D reconstructions of the accessible surface area. The study outcomes were accessible surface area of the talar dome in (1) total surface area and (2) sagittal plane distance of the talar dome at predetermined intervals.

RESULTS

The PM approach provided significantly more access to the talar dome than did the PL approach both with and without distraction (P < 0.001). The PM approach allowed access to 15.8% (SD = 4.7) of the talar dome without distraction and 26.4% (SD = 8.0, P < 0.001) of the talar dome with distraction. The PL approach provided access to 6.69% (SD = 2.69, P = 0.006 compared with PM) and 14.6% (SD = 6.24, P = 0.006 compared with PM) of the talar dome surface area without and with distraction. At the difficult to access posterocentral region (L50) of the talus, the PM approach without and with distraction allowed 26.7% (SD = 4.1) and 38.6% (SD = 5.6, P < 0.001) sagittal plane access compared with 18.7% (SD = 5.61, P = 0.03) and 27.5% (SD = 7.11, P = 0.003) through a PL approach.

CONCLUSION

The PM approach provides greater access to the posterocentral and PM talus. Using an external fixator for distraction can improve intraoperative visualization by at least 40%. This study provides a roadmap that can help guide talar dome surgical access for treatment of posterior talus fractures and help determine when an approach that includes an osteotomy can be avoided.

Limitations of accessibility of the talar dome with different open surgical approaches

PURPOSE

The aim of this study is to systematically review the current, relevant literature and provide a thorough understanding of the various open surgical approaches utilized to gain access to the talar dome for treatment of osteochondral lesions. Realizing the limits of access from soft tissue exposures and osteotomies, with and without external distraction, will help surgeons to select the appropriate approach for each individual clinical situation.

METHODS

A literature search was performed using three major medical databases: PubMed (MEDLINE), Scopus, and Embase. The Quality Appraisal for Cadaveric Studies (QUACS) scale was used to assess the methodological quality of each included study.

RESULTS

Of 3108 reviewed articles, nine cadaveric studies (113 limbs from 83 cadavers) evaluating the accessibility of the talar dome were included in the final analysis. Most of these (7/9 studies) investigated talar dome access in the context of treating osteochondral lesions of the talus (OLTs) requiring perpendicular visualization of the involved region. Five surgical approaches (anteromedial; AM, anterolateral; AL, posteromedial; PM, posterolateral; PL, and direct posterior via an Achilles tendon splitting; DP), four types of osteotomy (anterolateral tibial, medial malleolar, distal fibular, and plafondplasty), and two methods of distraction (Hintermann retractor and external fixator) were used among the included studies. The most commonly used methods quantified talar access in the sagittal plane (6/9 studies, 66.7%). The greatest exposure of the talar dome can be achieved perpendicularly by performing an additional malleolar osteotomy (90.9% for lateral, and 100% for medial). The methodological quality of all included studies was determined to be satisfactory.

CONCLUSION

Gaining perpendicular access to the central portion of the talar dome, measured in the sagittal plane, has clear limitations via soft tissue approaches either medially or laterally from the anterior or posterior aspects of the ankle. It is possible to access a greater talar dome area in a non-perpendicular fashion, especially from the posterior soft tissue approach. Various types of osteotomies can provide greater accessibility to the talar dome. This systematic review can help surgeons to select the appropriate approach for treatment of OLTs in each individual patient preoperatively.

LEVEL OF EVIDENCE

Level IV.

Why Make the Cut? Trochanteric Slide Osteotomy Can Improve Exposure to the Anterosuperior Acetabulum

OBJECTIVE

To define relative increases in visual bony surface area and access to critical landmarks with the addition of a trochanteric slide osteotomy to a Kocher-Langenbeck approach.

METHODS

A Kocher-Langenbeck approach followed by a trochanteric slide osteotomy was sequentially performed on 10, fresh-frozen, hemipelvectomy cadaveric specimens. Visual and palpable access to relevant surgical landmarks was recorded. Calibrated digital photographs were taken of each approach and analyzed using Image J.

RESULTS

The acetabular surface area exposed was 27.66 (±6.67) cm2 for a Kocher-Langenbeck approach. This increased to and 41.82 (±7.97) cm2 with the addition of a trochanteric osteotomy. The exposed surface area was increased by 51.2% for the trochanteric osteotomy (P < 0.001). The superior margin of the acetabulum could be visualized and palpably accessed in both exposures. Access to the more anterosuperior portions of the acetabulum was consistently possible in the trochanteric osteotomy but not with the Kocher-Langenbeck approach.

CONCLUSIONS

A trochanteric osteotomy may visually improve access to the most anterosuperior acetabulum but does not significantly improve surgical access to relevant portions of the superior acetabulum when compared with a Kocher-Langenbeck approach.

Comparison of four posterior approaches of the ankle: A cadaveric study

OBJECTIVES

The purpose of this study is to provide a detailed comparison of 4 posterior approaches of the ankle: the posteromedial, modified posteromedial (mPM), Achilles tendon-splitting (TS), and posterolateral approaches.

METHODS

Cadaveric dissections were performed to assess the influence of the medial and lateral retraction forces on the neuro-vascular bundle with suspension scales and to measure the medial and lateral exposed areas of the posterior tibia and talus. Data was acquired with the ankle in neutral position and in plantar flexion.

RESULTS

Both the mPM and TS approaches provided excellent visualization of the posterior tibia with the ankle in plantar flexion (16.6 cm2 and 16.2 cm2, respectively). The medial aspect of the posterior tibia, however, was significantly better exposed in the mPM approach than in the TS approach with the ankle in neutral position (8.9 cm2 vs 6.5 cm2). The lower value for medial retraction force in the mPM approach (1.9 N in neutral position and 0.9 N in plantar flexion) indicated a lower risk of injury to the neuro-vascular bundle (the tibial nerve and the posterior tibial artery). The posterior talus, however, is best visualized through the TS approach with the ankle in neutral position (4.5 cm2).

CONCLUSIONS

The current study demonstrated the usefulness of the mPM approach. When internal fixation of the fibula is unnecessary, the mPM approach is preferable, considering the potential damage to the Achilles tendon associated with the TS approach.

Radiographic correlation of clinical shoulder deformity and patient perception following scapula fracture

BACKGROUND

Interest in operative management of scapular fractures is increasing based upon defined radiographic displacement criteria and growing awareness that certain extra-articular fractures will not do well and result in dysfunction and deformity (slumped shoulder). We intend to quantify clinical deformity, analyze correlations of these novel measures with defined radiographic measures of fracture displacement and with the patients' reported perception of their deformity.

METHODS

Prospectively enrolled patients underwent standardized questioning regarding their perception of the deformity. Radiographs were utilized to measure glenopolar angle medial/lateral displacement, and angulation of the displaced scapula fracture. Novel measurements of clinical deformity (shoulder area, shoulder angle and shoulder height difference) were calculated. All measurements were repeated post-operatively for patients undergoing operative treatment.

RESULTS

Fifty-one patients (39 operative) were examined within 30 days of injury. Follow-up (≥2 months post-op) was obtained for 31/39 (79%). Medial-lateral displacement significantly correlated with all measures of clinical deformity and with patient reported shoulder appearance bothersome score. Angulation significantly correlated with patient perception and two clinical measures (shoulder area and shoulder angle difference). All post-operative radiographic measures, clinical measures of deformity, and patient reported scores statistically improved from baseline measures.

DISCUSSION

Patients with scapula fracture do perceive deformity, and there is a significant correlation between the patients' perception, radiographic and clinical measurements of deformity after scapula fracture. All measures statistically improved in patients with operative treatment compared to baseline measurements. This study reinforces the importance of the clinicians' clinical examination and observation of shoulder deformity in the scapula fracture patient.

LEVEL OF EVIDENCE

IV.

Access to the talar dome surface with different surgical approaches

BACKGROUND

Access to the talar dome for the treatment of osteochondral lesions (OCLs) can be achieved via several different approaches to the ankle joint. The recent description of an anatomical nine-grid scheme of the talus has proven useful to localise OCLs but no studies have demonstrated which approaches are indicated to access each of these zones. The aim of this study is to demonstrate the access afforded to each zone by each approach.

METHODS

Four standard soft tissue ankle approaches were performed simultaneously in ten fresh-frozen cadavers (anterolateral - AL, anteromedial - AM, posterolateral - PL, posteromedial - PM). The area of the talus, which was accessible with an instrument perpendicular to the surface was documented for each of the approaches. Using ImageJ software the surface area exposed with each approach was calculated. The talar dome was then divided using a nine-grid scheme and exposure to each zone was documented.

RESULTS

The AL, AM, PL and PM approaches allow for exposure of 24%, 25%, 5%, 7% of the talar dome respectively. The AL gives access to zones 3 (completely) and 2, 5, 6 (partially); the AM to zones 1 (completely) and 2, 4, 5 (partially); the PL to zones 9 and 8 (partially); and the PM to zones 7 and 8 (partially).

CONCLUSIONS

A large area of the talar dome cannot be easily accessed with the use of standard soft tissue approaches (39%). Minimal or no access is achieved for grid zones 4-6 and 8. In those instances careful preoperative planning is necessary and extended exposure can be achieved with the use of osteotomies, section of the ATFL or through modified approaches.

Does the Watson-Jones or Modified Smith-Petersen Approach Provide Superior Exposure for Femoral Neck Fracture Fixation?

BACKGROUND

A well-reduced femoral neck fracture is more likely to heal than a poorly reduced one, and increasing the quality of the surgical exposure makes it easier to achieve anatomic fracture reduction. Two open approaches are in common use for femoral neck fractures, the modified Smith-Petersen and Watson-Jones; however, to our knowledge, the quality of exposure of the femoral neck exposure provided by each approach has not been investigated.

QUESTIONS/PURPOSES

(1) What is the respective area of exposed femoral neck afforded by the Watson-Jones and modified Smith-Petersen approaches? (2) Is there a difference in the ability to visualize and/or palpate important anatomic landmarks provided by the Watson-Jones and modified Smith-Petersen approaches?

METHODS

Ten fresh-frozen human pelvi underwent both modified Smith-Petersen (utilizing the caudal extent of the standard Smith-Petersen interval distal to the anterosuperior iliac spine and parallel to the palpable interval between the tensor fascia lata and the sartorius) and Watson-Jones approaches. Dissections were performed by three fellowship-trained orthopaedic traumatologists with extensive experience in both approaches. Exposure (in cm) was quantified with calibrated digital photographs and specialized software. Modified Smith-Petersen approaches were analyzed before and after rectus femoris tenotomy. The ability to visualize and palpate seven clinically relevant anatomic structures (the labrum, femoral head, subcapital femoral neck, basicervical femoral neck, greater trochanter, lesser trochanter, and medial femoral neck) was also recorded. The quantified area of the exposed proximal femur was utilized to compare which approach afforded the largest field of view of the femoral neck and articular surface for assessment of femoral neck fracture and associated femoral head injury. The ability to visualize and palpate surrounding structures was assessed so that we could better understand which approach afforded the ability to assess structures that are relevant to femoral neck fracture reduction and fixation.

RESULTS

After controlling for age, body mass index, height, and sex, we found the modified Smith-Petersen approach provided a mean of 2.36 cm (95% confidence interval [CI], 0.45-4.28 cm; p = 0.015) additional exposure without rectus femoris tenotomy (p = 0.015) and 3.33 cm (95% CI, 1.42-5.24 cm; p = 0.001) additional exposure with a tenotomy compared with the Watson-Jones approach. The labrum, femoral head, subcapital femoral neck, basicervical femoral neck, and greater trochanter were reliably visible and palpable in both approaches. The lesser trochanter was palpable in all of the modified Smith-Petersen and none of the Watson-Jones approaches (p < 0.001). All modified Smith-Petersen approaches (10 of 10) provided visualization and palpation of the medial femoral neck, whereas visualization of the medial femoral neck was only possible in one of 10 Watson-Jones approaches (p < 0.001) and palpation was possible in eight of 10 Watson-Jones versus all 10 modified Smith-Petersen approaches (p = 0.470).

CONCLUSIONS

In the hands of surgeons experienced with both surgical approaches to the femoral neck, the modified Smith-Petersen approach, with or without rectus femoris tenotomy, provides superior exposure of the femoral neck and articular surface as well as visualization and palpation of clinically relevant proximal femoral anatomic landmarks compared with the Watson-Jones approach.

CLINICAL RELEVANCE

Open reduction and internal fixation of a femoral neck fracture is typically performed in a young patient (< 60 years old) with the objective of obtaining anatomic reduction that would not be possible by closed manipulation, thus enhancing healing potential. In the hands of surgeons experienced in both approaches, the modified Smith-Petersen approach offers improved direct access for reduction and fixation. Higher quality reductions and fixation are expected to translate to improved healing potential and outcomes. Although our experimental results are promising, further clinical studies are needed to verify if this larger exposure area imparts increased quality of reduction, healing, and improved outcomes compared with other approaches. The learning curve for the exposure is unclear, but the approach has broad applications and is frequently used in other subspecialties such as for direct anterior THA and pediatric septic hip drainage. Surgeons treating femoral neck fractures with open reduction and fixation should familiarize themselves with the modified Smith-Petersen approach.

A Preoperative Planning Tool: Aggregate Anterior Approach to the Humerus With Quantitative Comparisons

Extensile approaches to the humerus are often needed when treating complex proximal or distal fractures that have extension into the humeral shaft or in those fractures that occur around implants. The 2 most commonly used approaches for more complex fractures include the modified lateral paratricipital approach and the deltopectoral approach with distal anterior extension. Although the former is well described and quantified, the latter is often associated with variable nomenclature with technical descriptions that can be confusing. Furthermore, a method to expose the entire humerus through an anterior extensile approach has not been described. Here, we illustrate and quantify a technique for connecting anterior humeral approaches in a stepwise fashion to form an aggregate anterior approach (AAA). We also describe a method for further distal extension to expose 100% of the length of the humerus and compare this approach with both the AAA and the lateral paratricipital in terms of access to critical bony landmarks, as well as the length and area of bone exposed.

Comparison of Calcaneal Exposure Through the Extensile Lateral and Sinus Tarsi Approaches

The purpose of this study was to compare the exposure of the posterior facet with the extensile lateral (EL) approach compared with the sinus tarsi (ST) approach. We hypothesized that the ST approach will provide a similar exposure of the posterior calcaneal facet. A total of 8 sequential ST then EL approaches were performed on cadavers. Calcaneal landmarks were identified by visualization or palpation. Calibrated digital photographs of the posterior facet and lateral calcaneal body were obtained from standardized positions and used to calculate the exposed surface area. No significant difference was found in the average square area of the posterior facet exposed with the 2 approaches. Significantly more of the lateral calcaneal body was seen with the EL approach. Excluding the posterior facet superomedial quadrant, all the landmarks were visualized in 100% of approaches. The superomedial corner was visualized in significantly more of the cadavers with the EL approach and was palpable in 12.5% of the remaining cadavers in both approaches. Whereas the ST approach exposes less of the lateral wall of the calcaneus, it exposes similar amounts of the posterior facet when compared with the EL approach.

LEVELS OF EVIDENCE

Therapeutic, Level V.

Management of Nonunited Talar Fractures With Avascular Necrosis by Resection of Necrotic Bone, Bone Grafting, and Fusion With an Intramedullary Nail

BACKGROUND

The presence of nonunion of a talar fracture with displacement, together with complete avascular necrosis, is a challenging entity to treat.

METHODS

Twelve patients, 8 men (66.7%) and 4 women (33.3%), with nonunited talar fractures and extensive avascular necrosis of the talus were included. The average age was 27.7 years (range, 19-38 years). After exclusion of infection, the patients underwent resection of necrotic bone, bulk autograft, and fusion using an intramedullary nail. The posterior approach was used in 11 patients and the anterior approach in 1 patient. The primary outcome was solid osseous union at the ankle and subtalar level and between the talar head anteriorly and the posterior construct, as evidenced by computed tomographic examination. Functional assessment was performed with the American Orthopaedic Foot & Ankle Society score and subjective patient satisfaction Results: After a mean follow-up duration of 23 months (range, 12-60 months), solid osseous union was achieved in 8 patients (66.7%). Stable fibrous union was seen in 1 patient (8.3%). Three patients (25%) required reoperation, and osseous fusion was finally achieved. American Orthopaedic Foot & Ankle Society score improved from a mean of 39.3 (range, 12-56) preoperatively to 76.6 (range, 62-86) at last follow-up. Subjective patient satisfaction was graded good or excellent in all cases.

CONCLUSION

Resection of necrotic talar body and bulk autograft with tibiotalocalcaneal fusion by an intramedullary nail through a posterior approach was a reasonable option for the management of type IV posttraumatic talar deformity.

LEVEL OF EVIDENCE

Level IV, case series.

A Quantitative Exposure Planning Tool for Surgical Approaches to the Sacroiliac Joint

OBJECTIVES

To aid in surgical planning by quantifying and comparing the osseous exposure between the anterior and posterior approaches to the sacroiliac joint.

METHODS

Anterior and posterior approaches were performed on 12 sacroiliac joints in 6 fresh-frozen torsos. Visual and palpable access to relevant surgical landmarks was recorded. Calibrated digital photographs were taken of each approach and analyzed using Image J.

RESULTS

The average surface areas of exposed bone were 44 and 33 cm for the anterior and posterior approaches, respectively. The anterior iliolumbar ligament footprint could be visualized in all anterior approaches, whereas the posterior aspect could be visualized in all but one posterior approach. The anterior approach provided visual and palpable access to the anterior superior edge of the sacroiliac joint in all specimens, the posterior superior edge in 75% of specimens, and the inferior margin in 25% and 50% of specimens, respectively. The inferior sacroiliac joint was easily visualized and palpated in all posterior approaches, although access to the anterior and posterior superior edges was more limited. The anterior S1 neuroforamen was not visualized with either approach and was more consistently palpated when going posterior (33% vs. 92%).

CONCLUSIONS

Both anterior and posterior approaches can be used for open reduction of pure sacroiliac dislocations, each with specific areas for assessing reduction. In light of current plate dimensions, fractures more than 2.5 cm lateral to the anterior iliolumbar ligament footprint are amenable to anterior plate fixation, whereas those more medial may be better addressed through a posterior approach.

Glenoid diameter is an inaccurate method for percent glenoid bone loss quantification: analysis and techniques for improved accuracy

PURPOSE

To compare diameter-based glenoid bone loss quantification with a true geometric calculation for the area of a circular segment.

METHODS

By use of Maxima 12.01.0 mathematics modeling software (Macysma, Boston, MA), the diameter-based glenoid bone loss equation (% Bone loss = [Defect width (w)/Inferior glenoid circle diameter (D)] × 100%) was compared with a true geometric calculation for the area of a circular segment of the glenoid (Wolfram Research, Champaign, IL) rearranged in terms of w and D: Percent bone loss = (100/2π) (2 × arccos [1 - 2 (w/D)] - sin {2 × arccos [1 - 2 (w/D)]}). Percent error was calculated by taking the difference between the diameter equation and the true geometric calculation at varying true glenoid defect widths (w) (0% to 50% of diameter).

RESULTS

The commonly used diameter equation overestimated true glenoid bone loss at all values of w except at 0% and 50% of the diameter. The mean overestimation error was 3.9% ± 1.9% (range, 0.0% to 5.8%), with the maximum error occurring when w was 20% of the diameter: At this value, w/D × 100% (diameter equation) predicts 20% bone loss when true bone loss is actually 14.2%.

CONCLUSIONS

Diameter-based glenoid bone loss quantification overestimates true glenoid bone loss, with the maximum error occurring when theorized bone loss is 20%. To address situations for which a diameter-based bone loss quantification method must be performed or to improve the accuracy of surface-area calculations in previous diameter-based bone loss estimations, a corrective factor can be applied. Clinicians quantifying glenoid loss to make treatment decisions should be aware of the measurement methods used in the biomechanical studies on which they are basing their surgical decisions.

CLINICAL RELEVANCE

Diameter-based glenoid bone loss quantification overestimates true glenoid bone loss, with the maximum error occurring when theorized bone loss is 20%, a commonly used threshold for bone grafting.

Quantitative comparison of exposure for the posterior Judet approach to the scapula with and without deltoid takedown

BACKGROUND

The purposes of this study are to quantify the extent of the scapula exposed and to describe the osseous landmarks within the dissection of a posterior Judet approach with and without takedown of the posterior deltoid muscle.

METHODS

The posterior Judet approach using the muscular interval between the teres minor and infraspinatus muscle with and without takedown of the deltoid muscle was performed on 10 fresh-frozen cadaveric shoulders. Retractors with 2 kg of force were used at the wound margins for retraction. Upon completion of the exposure, a calibrated digital image was taken from the surgeon's perspective and specific anatomic landmarks were identified. The digital images were then analyzed with a computer software program, ImageJ (National Institutes of Health, Bethesda, MD, USA), to calculate the area (in square centimeters) of bone exposed.

RESULTS

The mean area of posterior scapula exposed by the traditional Judet approach with takedown of the deltoid muscle was 30.2 cm(2) (95% confidence interval, 27.7-32.7 cm(2)) compared with 27.3 cm(2) (95% confidence interval, 24.8-29.9 cm(2)) when the deltoid was not detached (P < .0001). In all 10 cadaveric shoulders, the posterior Judet approach without takedown of the deltoid muscle allowed access to the posterior glenoid, lateral scapula border, and spinoglenoid notch.

CONCLUSIONS

Although takedown of the deltoid muscle improves exposure, the posterior Judet approach without takedown of the posterior deltoid muscle allows for safe exposure to 91% of the bony scapula obtained by removing the deltoid muscle and access to the critical osseous fixation points of the posterior scapula.

Morphologic characteristics of the posterior malleolus fragment: a 3-D computer tomography based study

OBJECTIVES

The objective of this study was to evaluate the morphological characteristics of the posterior malleolus fragment (PMF) based on 3-D computed tomography scans, and evaluated the variability in different types of injuries (ankle fracture, spiral tibial shaft fracture and pilon fracture).

METHODS

A retrospective analysis of 3-D computed tomography data of PMF from June 2011 to February 2012 was conducted in a level 1 trauma centre. The cross angle (α), fragment length ratio (FLR), fragment area ratio (FAR), sagittal angle (θ), and fragment height (FH) were measured as morphologic assessments in the Picture Archiving and Communication System (PACS).

RESULTS

Based on the definition of the PMF, 144 cases were brought into this study. And the PMF was described with a mean α of 25.0°, a mean FAR of 17.66 %, a mean θ of 16.1° and a mean FH of 23.06 mm. Besides, this study showed a significant difference on FAR amongst the three injuries with the FAR was 30.31 % (P < 0.05) in pilon fracture group. Respectively, although the mean θ (16.1°) indicated a vertical fracture pattern, yet no significant difference was shown amongst the three groups.

CONCLUSIONS

Although the PMFs appear to be highly variable, most of the PMFs were located on the posterolateral of the distal tibia, and showed features with vertical nature. The information obtained from this study will be helpful for fracture models in a future biomechanical study and for determining appropriate surgical approaches.

Anatomical evaluation of different approaches for tibiotalocalcaneal arthrodesis

BACKGROUND

The transfibular approach is commonly used for tibiotalocalcaneal arthrodesis. However, the medial and the posterolateral approaches are available as alternatives. The present study was performed to assess the effects of the 3 approaches on the neurovascular structures encountered and to quantify the extent of cartilage in the different joint compartments that could be surgically debrided.

METHODS

This cadaver study was performed in 6 pairs of formalin-fixed legs (mean donor age: 80 years; 4 females, 2 males). For each approach, 4 specimens were selected. The neurovascular structures at risk and the debrided portions of the articular cartilage were compared.

RESULTS

Arterial structures were least compromised by the transfibular approach. The posterolateral approach was particularly likely to damage the lateral malleolar branches of the peroneal artery. Venous structures were at risk mainly from the medial approach, which was also the most risk-bearing of the 3 approaches in terms of nerve damage. The proportions of cartilage-debrided joint surfaces of the tibia in the ankle joint, and of the talus and the calcaneus in the subtalar joint, did not differ notably. The proportions of debrided surfaces of the talus in the ankle joint differed notably among the 3 approaches.

CONCLUSIONS

The medial approach could be a valid alternative to the lateral transfibular approach for tibiotalocalcaneal arthrodesis. Care should be taken, however, to prevent damage to the saphenous nerve and other neurological structures.

CLINICAL RELEVANCE

Access morbidity and feasibility of adequate cartilage debridement are relevant to the clinical outcome of hindfoot arthrodesis.