Quantification of the exposure of the glenohumeral joint from the minimally invasive to more invasive subscapularis approach to the anterior shoulder: a cadaveric study

Which surgical approach provides maximum visualization and access for open reduction and internal fixation (ORIF) of femoral neck fractures?

OBJECTIVES

Appropriate visualization of the femoral neck is critical when performing open reduction and internal fixation (ORIF) of a femoral neck fracture. The purpose of this study was to objectively identify which surgical approach provided the most extensive visualization of the femoral neck during ORIF. Our hypothesis was that the Smith-Petersen approach with rectus release would provide the most extensive visualization.

METHODS

Ten cadaveric hips were utilized to compare 4 different surgical approaches to the femoral neck: Smith-Petersen (SP), Smith-Petersen with rectus release (SPwR), Watson-Jones (WJ), and Hueter approach. After surgical exposure, calibrated digital images were captured and analyzed using a computer software program to determine the percent-area visualized. Three trained investigators separately assessed each specimen to determine clinical visualization and ability of the surgeon to manually outline anatomic locations of the femoral neck: subcapital, trans-cervical, and basicervical. Data were analyzed for significant (p < 0.05) differences using ANOVA and Fisher Exact tests.

RESULTS

For calculated percent-visualization, SP and SPwR allowed for significantly more (p = 0.003) visualization than the Hueter and WJ approaches. For surgeon visualization, SP and SPwR were significantly higher (p < 0.029) when compared to WJ. The ability for the individual surgeon to outline the femoral neck's anatomical landmarks was significantly higher (p < 0.049) with SP and Hueter approaches compared with SPwR.

CONCLUSION

The SP and SPwR provided superior visualization of femoral neck anatomy compared to Hueter and WJ approaches. Similarly, the SP approach allowed for optimal surgeon visualization of and access to clinically relevant femoral neck anatomic landmarks compared to other approaches assessed.

Development and ex-vivo assessment of a novel patient specific guide and instrumentation system for minimally invasive total shoulder arthroplasty

Objective

To develop and assess a novel guidance technique and instrumentation system for minimally invasive short-stemmed total shoulder arthroplasty that will help to reduce the complications associated with traditional open replacement such as poor muscle healing and neurovascular injury. We have answered key questions about the developed system including (1) can novel patient-specific guides be accurately registered and used within a minimally invasive environment?; (2) can accuracy similar to traditional techniques be achieved?

Methods

A novel intra-articular patient-specific guide was developed for use with a new minimally invasive posterior surgical approach that guides bone preparation without requiring muscle resection or joint dislocation. Additionally, a novel set of instruments were developed to enable bone preparation within the minimally invasive environment. The full procedure was evaluated in six cadaveric shoulders, using digitizations to assess accuracy of each step.

Results

Patient-specific guide registration accuracy in 3D translation was 2.2±1.2mm (RMSE±1 SD; p = 0.007) for the humeral component and 2.7±0.7mm (p<0.001) for the scapula component. Final implantation accuracy was 2.9±3.0mm (p = 0.066) in translation and 5.7–6.8±2.2–4.0° (0.001<p<0.009) across the humerus implants’ three rotations. Similarly, the glenoid component’s implantation accuracy was 3.0±1.7mm (p = 0.008) in translation and 2.3–4.3±2.2–4.4° (0.008<p<0.09) in rotation.

Conclusion

This system achieves minimally invasive shoulder replacement with accuracy similar to traditional open techniques while avoiding common causes of complications.

Significance

This novel technique could lead to a paradigm shift in shoulder arthroplasty for patients with moderate arthritis, which could significantly improve rehabilitation and functional outcomes.

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.

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.

Glenoid exposure in total shoulder arthroplasty

Glenoid exposure is agreed to be a difficult step, but is also a key step in total shoulder arthroplasty, both anatomic and reverse. It conditions unhindered use of the ancillary instrumentation and thus correct glenoid component positioning. The main stages comprise arthrotomy, by opening the rotator cuff, humeral head cut, and inferior glenohumeral release, enabling shifting of the humerus and good exposure of the glenoid cavity. The two main approaches are deltopectoral and anterosuperior transdeltoid. Using the deltopectoral approach, arthrotomy is performed through the subscapularis muscle, by various techniques. This approach enables extensive inferior glenohumeral release and thus an approach to the inferior apex of the glenoid cavity, which is a key area for glenoid implant positioning. The main drawbacks are postoperative shoulder instability and limited access to the posterior part of the glenoid in case of significant retroversion. Moreover, subscapularis healing is uncertain, which can impair the clinical outcomes, with risk of glenoid component loosening. Advantages, on the other hand, include the fact that it can be implemented in all cases, even the most difficult ones, and that the deltoid muscle is respected. The transdeltoid approach has the advantage of being simple, providing direct exposure of the glenoid cavity through a rotator cuff tear after passing through the deltoid. It is therefore especially indicated for reverse prosthesis in case of rotator cuff tear, and in traumatology. However, the approach to the inferior part of the glenoid cavity can be restricted, with insufficient exposure and a risk of glenoid component malpositioning (superior tilt). The preoperative assessment is essential, to detect at-risk situations such as severe stiffness and anticipate difficulties in glenoid exposure.

Latarjet procedure using subscapularis split approach offers better rotational endurance than partial tenotomy for anterior shoulder instability

PURPOSE

Latarjet, which is a coracoid bone block procedure, is an effective treatment for anterior shoulder instability with glenoid bone loss. During this reconstructive procedure the subscapularis may be tenotomized or be split to expose the glenoid neck. The aim of this study was to assess the effect of subscapularis management on functional outcomes and internal and external rotation durability and strength. Hypothesis is that the subscapularis split approach will result in better functional results and superior internal rotation strength and endurance.

METHODS

The study included 48 patients [median age 30 (range 16-69); 42 males, 6 females], who underwent a modified Latarjet procedure for anterior shoulder instability. There were 20 patients in the subscapularis tenotomy group and 28 patients in the subscapularis split group. The groups were compared isokinetically using a computerized dynamometer for internal and external rotation durability and strength. At the latest follow-up, the patients were evaluated with the American Shoulder and Elbow Surgeons (ASES) and ROWE scores for functional outcomes.

RESULTS

At a median follow-up period of 25 (range 12-73) months after the Latarjet procedure, the internal rotation durability was significantly higher in the split group (p = 0.045). However, a statistically significant difference could not be found for internal and external rotational strengths (n.s.). There was also no significant difference between the final ASES and ROWE scores (n.s.).

CONCLUSION

Although both approaches offer promising results, the subscapularis split approach appears to provide better internal rotation durability compared to subscapularis tenotomy. Therefore, the subscapularis split approach may be more preferable for the management of the subscapularis muscle during Latarjet procedure.

LEVEL OF EVIDENCE

Retrospective cohort study, Level III.

Increased Anterior Column Exposure Using the Anterior Intrapelvic Approach Combined With an Anterior Superior Iliac Spine Osteotomy: A Cadaveric Study

OBJECTIVE

To determine whether the addition of an anterior superior iliac spine (ASIS) osteotomy to the lateral window, when combined with the anterior intrapelvic (AIP) surgical approach, would improve visualization of the iliopectineal eminence and allow for predictable and safe clamp application.

METHODS

Ten lateral window approaches to the iliac fossa were developed in conjunction with the AIP approach on 10 fresh-frozen cadaveric pelvi. A calibrated digital image was taken from the surgeon's optimal viewing angle to capture the visualized osseous surface of the false pelvis with emphasis on the iliopectineal eminence. An ASIS osteotomy was then performed and an additional calibrated image was obtained to identify any increased visualization of the iliopectineal eminence. Using ImageJ software (NIH, Bethesda, MD), the additional surface area afforded to the surgeon was calculated. An AIP approach was then performed to confirm complete exposure of the anterior column and whether a Weber clamp could safely be placed across the iliopectineal eminence.

RESULTS

The lateral window, osteotomy, and AIP approach were successfully accomplished in all 10 specimens. Before performing an ASIS osteotomy, a mean of 20.3 cm (range: 14.5-25.6 cm) of the false pelvis adjacent to the pelvic brim was visualized. After completion of the osteotomy, the mean visualized surface area increased significantly to 28.4 cm (range: 14.6-45.6 cm) (P < 0.0168). Clamp placement through the lateral window was unsuccessful in all 10 specimens. After completion of the AIP approach, complete visualization of the iliopectineal eminence was confirmed and safe clamp application through the lateral window possible in all 10 specimens.

CONCLUSION

ASIS osteotomy through the lateral window significantly improved visualization and access to the iliopectineal eminence in this cadaveric model, which suggests that it may be a suitable alternative to the traditional ilioinguinal approach for select fracture patterns when combined with an AIP approach.

The Deltoid Lift: A Comparison Study of Exposure Area in Proximal Humeral Approaches

BACKGROUND

Adequate exposure of the proximal humerus is necessary to address atypical or complex proximal humerus fractures and orthopedic tumors. Surgical management may be difficult through existing approaches due to their limited nature and the delicate neurovascular anatomy of the shoulder. The deltoid lift, a previously described extensile approach, can be incorporated into the surgeon's armamentarium as an alternative exposure to the proximal humerus. The objective of this study was to quantify and compare the humeral exposure achieved through the deltoid lift with the standard direct lateral deltoid-splitting, anterolateral acromial, and deltopectoral approaches in terms of surface area and exposure of key anatomic landmarks.

METHODS

Each approach was performed a minimum of 8 times on 18 cadaveric specimens. After identifying landmarks, exposure area of exposed humerus was quantified using digital images and ImageJ software.

RESULTS

The deltoid lift yielded an average exposure area of 46 cm². Comparison of the exposure area for the deltoid lift against each of the other approaches yielded statistical significance ( P < .01). The exposure provided was 2-folds greater than that of the next most extensive approach. All anatomic landmarks were directly visible through the deltoid lift as compared with the remaining approaches, through which only 1 landmark was directly visualized and only 2 of the 3 remaining were palpable through the approach.

CONCLUSIONS

The deltoid lift extensile surgical exposure to the proximal humerus provides the largest humeral exposure with the greatest visibility of landmarks relative to the 3 most widely utilized standard approaches.

Management of the subscapularis tendon during total shoulder arthroplasty

Use of total shoulder arthroplasty has significantly increased during the past decade. For anatomic total shoulder arthroplasty, controversy exists regarding the best technique for detachment and repair of the subscapularis tendon. Options include tendon tenotomy, peel, lesser tuberosity osteotomy, and even subscapularis-sparing techniques. Inadequate healing of the subscapularis tendon can lead to postoperative pain, weakness, and instability. This review discusses the subscapularis pathoanatomy, different techniques for releasing and repairing the tendon, and reports biomechanical and clinical outcomes for each technique after total shoulder arthroplasty.

Rotator cuff-sparing approaches for glenohumeral joint access: an anatomic feasibility study

BACKGROUND

The deltopectoral approach for total shoulder arthroplasty can result in subscapularis dysfunction. In addition, glenoid wear is more prevalent posteriorly, a region difficult to access with this approach. We propose a posterior approach for access in total shoulder arthroplasty that uses the internervous interval between the infraspinatus and teres minor. This study compares this internervous posterior approach with other rotator cuff-sparing techniques, namely, the subscapularis-splitting and rotator interval approaches.

METHODS

The 3 approaches were performed on 12 fresh frozen cadavers. The degree of circumferential access to the glenohumeral joint, the force exerted on the rotator cuff, the proximity of neurovascular structures, and the depth of the incisions were measured, and digital photographs of the approaches in different arm positions were analyzed.

RESULTS

The posterior approach permits direct linear access to 60% of the humeral and 59% of the glenoid joint circumference compared with 39% and 42% for the subscapularis-splitting approach and 37% and 28% for the rotator interval approach. The mean force of retraction on the rotator cuff was 2.76 (standard deviation [SD], 1.10) N with the posterior approach, 2.72 (SD, 1.22) N with the rotator interval, and 4.75 (SD, 2.56) N with the subscapularis-splitting approach. From the digital photographs and depth measurements, the estimated volumetric access available for instrumentation during surgery was comparable for the 3 approaches.

CONCLUSION

The internervous posterior approach provides greater access to the shoulder joint while minimizing damage to the rotator cuff.

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.

A Comparison of Exposure Between the Classic and Modified Judet Approaches to the Scapula

OBJECTIVES

A debate exists over the optimal approach for addressing fractures of the scapula and glenoid. The purpose of this study is to (1) quantify and compare osseous exposure using modified Judet (MJ) and classic Judet (CJ) approaches and (2) assess the change in scapular exposure after triceps release from the inferior glenoid.

METHODS

Ten arms on 5 fresh-frozen torsos underwent MJ and CJ approaches. A triceps release was performed following the CJ approach in all specimens. Visual and/or palpable access to relevant surgical landmarks was recorded. Calibrated digital photographs were taken of each approach and analyzed using Image J (NIH, Bethesda, MD) to calculate the surface area of exposed bone.

RESULTS

The MJ and CJ approaches exposed 16.8 (±7.58) cm(2) and 98.6 (±25.39) cm(2) of bone, respectively (P < 0.001). The full medial and lateral borders of the scapula were visualized in all approaches with mobilization of the teres minor. Palpable access to the full scapular spine was possible in all cadavers. Although the MJ and CJ approaches only allowed the inferior gleniod neck to be visualized in 1 and 2 specimens, respectively, performing a triceps release provided access to this structure. It also increased the CJ exposure by 12.6 cm(2) (P < 0.001) and allowed palpation of the anterior glenoid margin in 100% of specimens.

CONCLUSIONS

In conclusion, the MJ approach allows similar access to landmarks important for reduction and fixation while exposing only 20% of the surface area typically visualized with the CJ approach.

The Deltoid Lift: A Cadaveric Analysis and the Literature Review of a Novel Surgical Approach to the Proximal Humerus

Obtaining adequate exposure of the proximal humerus for anatomic reduction of complex intra-articular fractures or in the surgical treatment of tumor may be difficult. Here we describe a novel approach to the proximal humerus: the deltoid lift, and perform a cadaveric analysis objectively quantifying the exposure. The deltoid lift offers significantly greater exposure to the proximal humerus as compared with the deltopectoral approach.