Sreevathsa Boraiah

Indirect Medial Reduction and Strut Support of Proximal Humerus Fractures Using an Endosteal Implant

Fractures of the proximal humerus, particularly in osteoporotic bone, are still frequently referred to as unsolved fractures. The recent explosion of locking plate technology has included these fractures, but it appears that laterally placed locking plates may not be as predictable as hoped. Medial column mechanical support of these fractures may play a significant role in the ultimate stability of fixation during rehabilitation until healing occurs. We have devised a technique of using a segment of fibula allograft, placed endosteally and incorporated into the locking construct, to aid in the reduction and restoration of the mechanical integrity of the medial column of the proximal humerus.

Direct visualization for syndesmotic stabilization of ankle fractures.

Background: Ankle fractures with syndesmotic injury treated via standard trans-syndesmotic fixation have a high percentage of syndesmotic malreduction. 10 We established a protocol involving both direct syndesmosis visualization and meticulous tibial incisura reconstruction via the posterior malleolus fracture fragment, when present, via the attached, intact PITFL, then compared this with historic controls to assess improvement after this type of syndesmosis reconstruction. Materials and Methods: One hundred forty-nine consecutive direct visualization patients were treated prospectively with either open posterior malleolus reduction and fixation, regardless of fragment size (“PM”: 38 patients), or, with no posterior malleolar fracture, open fixation with locked syndesmotic screws (“S”: 97 patients); fracture-dislocations combined both fixation types (“C”: 16 patients). The syndesmosis was opened and debrided in all. All patients had preoperative MRI and postoperative CT. Distances between the fibula and anterior and posterior incisura facets were measured on axial CT. An incongruent joint was defined as an A-P difference greater than 2 mm. Our historic controls were 25 patients previously fixed via indirect, fluoroscopic reduction and syndesmotic screws. Results: In the direct visualization group, 24 ankles (16%) had incongruity, compared with 13 controls (52%). The average difference between anterior and posterior colliculi measurements between PM and C was significant (p = 0.017). Conclusion: Malreductions were significantly decreased in the direct visualization group. However, our reduction sometimes remains imprecise, even with direct visualization and attention to detail. Also, posterior malleolar reconstruction was more accurate than syndesmotic screw fixation in our study.

Complications of Recombinant Human BMP-2 for Treating Complex Tibial Plateau Fractures: A Preliminary Report

Bone morphogenic proteins (BMPs) are potent osteoinductive agents. Their use in fracture surgery is still being studied and the clinical indications are evolving. Heterotopic bone after BMP use in spine surgery is a known complication. While some literature describes the ability of BMP to enhance fracture healing, few articles describe complications of BMP. In tibial plateau fractures, after elevating the cartilage en mass, a subchondral void may be created in these fractures. Structural support provided by bone void-filling agents can be augmented with osteoinduction achieved by BMP. We asked whether heterotopic bone formation would occur more frequently with BMP-2 when used in tibial plateau fractures and whether BMP-2 enhanced the ability to maintain surgically restored subchondral bone integrity. Heterotopic bone developed more frequently in patients receiving BMP (10 of 17) than in patients not receiving BMP (one of 23). Four patients receiving BMP and no patients not receiving BMP underwent removal of heterotopic bone. Maintenance of subchondral bone integrity was similar without and with the use of BMP. BMP is a potent osteoinductive agent; however, when used for an off-label indication in periarticular situations, complications such as heterotopic bone are common and increase reoperation rates.Level of Evidence: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Quantitative Assessment of the Vascularity of the Proximal Part of the Humerus

BACKGROUND The current consensus in the literature is that the anterolateral branch of the anterior humeral circumflex artery provides the main blood supply to the humeral head. While the artery is disrupted in association with 80% of proximal humeral fractures, resultant osteonecrosis is infrequent. This inconsistency suggests a greater role for the posterior humeral circumflex artery than has been previously described. We hypothesized that the posterior humeral circumflex artery provides a greater percentage of perfusion to the humeral head than the anterior humeral circumflex artery does. METHODS In twenty-four fresh-frozen cadaver shoulders (twelve matched pairs), we cannulated the axillary artery proximal to the thoracoacromial branch and ligated the brachial artery in the forearm. In each pair, one shoulder served as a control with intact vasculature and, in the contralateral shoulder, either the anterior humeral circumflex artery or the posterior humeral circumflex artery was ligated. Gadolinium was injected through the cannulated axillary arteries, and magnetic resonance imaging was performed. After imaging, a urethane polymer was injected, and specimens were dissected. For volumetric analysis, the gadolinium uptake on the magnetic resonance imaging was quantified in each quadrant of the humeral head with use of a custom automated program. The gadolinium uptake was compared between the control and ligated sides and between the ligated anterior humeral circumflex artery and ligated posterior humeral circumflex artery groups. RESULTS The posterior humeral circumflex artery provided 64% of the blood supply to the humeral head overall, whereas the anterior humeral circumflex artery supplied 36%. The posterior humeral circumflex artery also provided significantly more of the blood supply in three of the four quadrants of the humeral head. CONCLUSIONS The finding that the posterior humeral circumflex artery provides 64% of the blood supply to the humeral head provides a possible explanation for the relatively low rates of osteonecrosis seen in association with displaced fractures of the proximal part of the humerus. In addition, protecting the posterior humeral circumflex artery during the surgical approach and fracture fixation may minimize loss of the blood supply to the humeral head.

Anatomy and Dimensions of the Gluteus Medius Tendon Insertion

PURPOSE The purpose of this study was to determine the area, dimensions, and orientation of the gluteus medius footprint to provide an improved understanding of its insertional anatomy. METHODS Eight fresh-frozen cadaveric hips were dissected, leaving only the most distal gluteus medius tendon attached to the greater trochanter. The tendon insertion footprint and proximal femur were digitized and mapped by use of 3-dimensional computer navigation software. The area, location, and dimensions of the tendon insertion were determined. RESULTS The gluteus medius tendon has 2 distinct insertion sites on the greater trochanter, the lateral facet and the superoposterior facet. The mean areas of insertion onto the lateral and superoposterior facets were 438.0 mm2 (SD, 57.7 mm2) and 196.5 mm2 (SD, 48.4 mm2), respectively. The lateral facet footprint had a mean longitudinal dimension of 34.8 mm (SD, 4.3 mm), was angled at a mean of 36.8 degrees (SD, 6.7 degrees ) relative to the long axis of the femur, and had a mean minimum width of 11.2 mm (SD, 1.8 mm). The superoposterior facets shape approximated that of a circle, with a mean diameter of 17 mm (SD, 2.0 mm). CONCLUSIONS The gluteus medius tendon has 2 distinct and consistent insertion sites onto the greater trochanter. This information will provide surgeons with a better understanding of the footprint anatomy when evaluating gluteus medius tendon tears. CLINICAL RELEVANCE Gluteus medius tendon tears can be a source of significant pain and morbidity. This study describes the anatomic morphology of this tendon insertion, which should aid in its repair when necessary.

Open Reduction Internal Fixation and Primary Total Hip Arthroplasty of Selected Acetabular Fractures

Objective: The purpose of our study was to analyze the outcomes of patients treated with combined open reduction internal fixation (ORIF) and primary total hip arthroplasty (THA) for selected cases of acetabular fractures. Design: Retrospective case series. Setting: University Medical Center. Patients and Participants: Four hundred twenty patients underwent ORIF for displaced acetabular fractures at our institution. Twenty-one of these patients underwent ORIF and primary THA. All surgeries were performed under the direct supervision of a fellowship-trained orthopaedic trauma surgeon and a fellowship trained adult reconstructive surgeon who acted as a cosurgeon. At the time of review, 18 patients met the 1-year follow-up requirement and formed the study cohort. Mean patient age was 71 years (range 55-86 years). There was 1 transverse fracture, 1 anterior column posterior hemitransverse and 1 both-column fracture. There were 15 posterior wall fractures. Of the 15 posterior wall fractures, 1 was associated with posterior column fracture, 1 with dome fracture, 2 with transverse fractures, and 9 with femoral head impaction fracture. There were 2 patients with isolated posterior wall fractures. Clinical outcomes were analyzed using Harris hip score. Radiographs were analyzed for implant migration and loosening around the implant. Results: Of the 18 patients in the study, 14 patients were followed for more than 2 years (average 3.9 years, range 1-10.1 years). All but 1 patient healed successfully. One patient required revision and placement of a constrained prosthesis due to failure of acetabular component, 3 weeks post-index procedure. Harris hip score ranged from 78 to 99 with a mean of 88. The radiographs showed an average medial displacement of 1.2 mm (range 0-3 mm) and an average vertical displacement of 1.3 mm (range 0-4 mm). There was no radiographic evidence of acetabular component loosening, but loosening was evident on 1 uncemented femoral stem. Conclusions: Treatment of acetabular fractures remains challenging particularly in the presence of severe osteopenia, comminution, or associated femoral head fracture. In appropriately selected patients, ORIF and primary THA provide an acceptable treatment option.

The anterolateral acromial approach for fractures of the proximal humerus.

Displaced and unstable fractures of the proximal humerus are notoriously difficult to manage. Successful surgical treatment requires finding the appropriate balance between adequate exposure for reduction and rigid fixation and minimizing soft tissue dissection. The anterolateral acromial approach was developed to allow less invasive treatment of proximal humerus fractures. The plane of the avascular anterior deltoid raphe is utilized, and the axillary nerve is identified and protected. Anterior dissection near the critical blood supply is avoided, substantial muscle retraction is minimized, and the lateral plating zone is directly accessed. Over a 4-year period, 52 patients with acute displaced fractures of the proximal humerus were treated with the anterolateral acromial approach and either a locking plate or an intramedullary nail. Twenty-three patients were evaluated clinically at a minimum follow-up of 1 year (average, 28 months) by clinical examination for range of motion and nerve function and a QuickDASH score. There were no axillary nerve deficits postoperatively related to the approach, and the average QuickDASH score was 25.2 (0, best; 100, worst). This approach allowed direct access to the lateral fracture planes for fracture reduction and plate placement or safe nail and interlocking screw placement.

Assessment of vascularity of the femoral head using gadolinium (Gd-DTPA)-enhanced magnetic resonance imaging: A CADAVER STUDY

In spite of extensive accounts describing the blood supply to the femoral head, the prediction of avascular necrosis is elusive. Current opinion emphasises the contributions of the superior retinacular artery but may not explain the clinical outcome in many situations, including intramedullary nailing of the femur and resurfacing of the hip. We considered that significant additional contribution to the vascularity of the femoral head may exist. A total of 14 fresh-frozen hips were dissected and the medial circumflex femoral artery was cannulated in the femoral triangle. On the test side, this vessel was ligated, with the femoral head receiving its blood supply from the inferior vincular artery alone. Gadolinium contrast-enhanced MRI was then performed simultaneously on both control and test specimens. Polyurethane was injected, and gross dissection of the specimens was performed to confirm the extraosseous anatomy and the injection of contrast. The inferior vincular artery was found in every specimen and had a significant contribution to the vascularity of the femoral head. The head was divided into four quadrants: medial (0), superior (1), lateral (2) and inferior (3). In our study specimens the inferior vincular artery contributed a mean of 56% (25% to 90%) of blood flow in quadrant 0, 34% (14% to 80%) of quadrant 1, 37% (18% to 48%) of quadrant 2 and 68% (20% to 98%) in quadrant 3. Extensive intra-osseous anastomoses existed between the superior retinacular arteries, the inferior vincular artery and the subfoveal plexus.

Osteochondral Lesions of Talus Associated with Ankle Fractures

Background: Residual ankle pain and stiffness is not uncommon after ankle fractures. Proposed etiologies include ligamentous instability, joint arthrosis and osteochondral injuries. We studied the incidence of osteochondral lesions of the talus (OCLT) with various ankle fracture patterns and assessed their impact on functional outcome. Materials and Methods: Preoperative MRI of 153 patients with ankle fractures who underwent operative fixation was studied. Ligamentous structures around the ankle and OCLT were assessed by MRI. The OCLT was graded as follows: 0, normal; 1, hyperintense but morphologically intact cartilage; 2, fibrillations or fissures not extending into the bone; 3, cartilage flap or bone exposed; 4, loose undisplaced fragment; 5, displaced fragments. Functional outcome was assessed using Foot and Ankle Outcome Scoring (FAOS) at a minimum of 6 months. Outcome between the OCLT and non OCLT group with similar fracture pattern was compared using Fischers exact test. Results: There were 26 (17%) associated OCLT; four grade I, five grade II, one grade III, eight grade IV, and eight grade V lesions. Three were associated with supination adduction, 21 with supination external rotation injuries and two with pronation external rotation injuries. In the OCLT and the non OCLT group, the average symptom score, pain score, activities of daily living score, sports/recreation score and quality of life score was 80, 72, 79, 45, 50 and 73, 73, 79, 60, 45, respectively. There was no statistically significant difference between the two groups (p > 0.1). Conclusion: Osteochondral lesions were frequently associated with ankle fractures; however they had no significant impact on the functional outcome when associated with ankle fractures.

Predictable healing of femoral neck fractures treated with intraoperative compression and length-stable implants.

OBJECTIVES A healed, yet shortened, femoral neck has historically been deemed a success in fracture treatment. This, however, comes at the price of diminished physical function and quality of life. We analyzed the outcomes of our treatment algorithm, which attempts to minimize postoperative shortening of femoral neck fractures and determined which preoperative factors were associated with femoral neck shortening and failure of surgical fixation. LEVEL OF EVIDENCE This is level IV retrospective study. MATERIALS Fifty-four patients underwent open reduction and internal fixation for acute femoral neck fracture with nonsliding constructs. The collapse of the femoral neck in the horizontal (X), vertical (Y), and along the resultant along the (Z) vector (X+Y=Z) was measured on anteroposterior radiographs corrected for leg rotation. The migration of the superior-most screw tip in all axes was measured. Age, gender, Garden grade, and Pauwels angle were analyzed for their association with shortening or failure of surgical fixation. RESULTS The average age of the patients was 78.1 years. There were 23 Garden I, 2 Garden II, 14 Garden III, and 15 Garden IV fractures. Fifty-one (94%) healed successfully without complications. The minimum follow-up was 9 months (average, 17.6 months; range, 9-30 months). Surgical fixation failed in two patients, and one patient developed avascular necrosis. The average displacement of the femoral head and the screw tip was 1.23, 0.86, 1.98 mm and 0.7 mm, 0.9 mm, and 1.7 mm in the X, Y, and Z (resultant) vectors, respectively. DISCUSSION With careful consideration to reduction, we fixed femoral neck fractures with nonsliding constructs, resulting in a high union rate with very minimal shortening of the femoral neck.