Effect of glenoid perforation during total shoulder arthroplasty on glenoid component cement fixation and suprascapular nerve.

BACKGROUND: Arthritic glenoids are susceptible to vault perforation during total shoulder arthroplasty. We investigated the effects of glenoid perforation and subsequent cement extrusion on the suprascapular nerve and on the glenoid cement infiltration. METHODS: Total shoulder arthroplasty using three-pegged glenoid components were performed on 10 cadaveric shoulders assigned to two groups (perforation vs. control). In perforation group, the glenoids were reamed eccentrically and intentionally perforated medially through the central peg hole, whereas control group received perpendicular reaming with no perforation. Bone cement was applied to each peg. Spatial relationship between the extruded cement and the suprascapular nerve, and the amount of cement infiltration into the cancellous bone were evaluated. RESULTS: In perforation group, five specimens were perforated anteriorly, and two posteriorly. In the two posteriorly perforated specimens, the suprascapular nerve was in direct contact with extruded cement at the spinoglenoid notch. Perforation group showed significantly less cement infiltration into the cancellous bone than control group (p = 0.008). CONCLUSIONS: Glenoid perforation decreases the volume of cement infiltration into the cancellous bone potentially compromising glenoid component fixation. Glenoid perforation tends to occur anteriorly rather than posteriorly in arthritic glenoids; however, if perforation occurs posteriorly, the suprascapular nerve is at immediate risk from the extruded cement.Level of evidence: Basic science study.

Interdepartmental imaging protocol for clinically based three-dimensional computed tomography can provide accurate measurement of glenoid version.

BACKGROUND: Conventional computed tomography (CT) is not accurate for glenoid version measurement. This study sought to examine the feasibility of an interdepartmental protocol implemented between orthopedic surgery and radiology departments for acquisition of anatomic axial CT images and to validate the glenoid version measured through such a protocol. MATERIALS AND METHODS: Data of 30 conventional CT scans of 10 normal and 20 osteoarthritic glenoids were transferred to clinical 3-dimensional imaging software by a radiology technician trained for the study. The technician independently reoriented the scapulae to generate anatomic CT images. A separate team of orthopedic researchers used laboratory-based 3-dimensional reconstruction software (Mimics; Materialise, Leuven, Belgium) to generate anatomic axial images. Three independent examiners measured glenoid version on the conventional CT, reoriented anatomic CT, and Mimics images at the superior, middle, and inferior levels. Data were analyzed using the Mimics data as the "gold standard." RESULTS: Reoriented anatomic CT images generated by the technician resulted in almost identical version measurements to the Mimics images in both normal and arthritic glenoids. The conventional CT images had poor agreement with the Mimics images in normal glenoids but had good agreement in arthritic glenoids. Both normal and arthritic glenoids had increased retroversion superiorly (P < .05), and this phenomenon was significantly exaggerated on the conventional CT images (P < .05). CONCLUSIONS: This study demonstrated that an interdepartmental protocol can produce reoriented anatomic axial CT images on which true glenoid version can be accurately measured. Such an institutional protocol would help surgeons accurately evaluate glenoid version preoperatively with reduced workload and expense.

Self-Reported Outcomes for Patients Undergoing Revision Carpal Tunnel Surgery With or Without Hypothenar Fat Pad Transposition.

BACKGROUND: Carpal tunnel surgery is the most common surgical procedure performed on the hand. Although complications are rare, recurrent or persistent carpal tunnel syndrome can be a significant problem after primary decompression. Various procedures have been described for the treatment of these patients including repeat decompression and hypothenar fat pad transposition. The purpose of this study is to compare the outcomes of patients undergoing revision carpal tunnel decompression with and without hypothenar fat pad transposition. METHODS: We performed a retrospective review of all patients undergoing revision carpal tunnel surgery at our institution between 2002 and 2014. Identified patients were contacted by telephone. A Boston Carpal Tunnel Questionnaire (BCTQ) was administered to all participants. RESULTS: Seventy-six patients underwent revision carpal tunnel surgery over the study period. Twenty-nine of 45 potential participants provided a survey response (64.9%) representing a total of 33 carpal tunnel revision surgeries. Seventeen hands underwent repeat decompression alone, and 16 hands underwent repeat decompression with hypothenar fat pad transposition. A trend toward improved overall BCTQ score was noted for patients undergoing decompression alone; however, no significant difference was determined for total survey score by procedure type. Similarly, total symptom severity and functional scores were not statistically significant between groups; however, a trend toward significance for improved symptom severity score was observed in patients undergoing decompression alone. CONCLUSIONS: Our results reveal no difference in self-reported symptom severity and functional scores between patients undergoing revision carpal tunnel surgery with repeat decompression alone or decompression with fat pad transposition.

Fixation of Displaced Medial Epicondyle Fractures in Adolescents.

BACKGROUND: Open reduction and internal fixation of displaced medial epicondyle fracture dislocations in adolescents is recommended for incarceration of the epicondyle in the joint and for athletes who need a stable elbow for their sport. A screw placed across the epicondyle into the medial column avoiding the olecranon fossa is a common fixation method. One author has recommended adding a metal washer to the screw fixation because of the perceived risk of epicondyle fragmentation or penetration when using a screw alone. The purpose of this study was to determine whether the use of a screw and washer for the fixation of pediatric medial epicondyle fractures results in less fragmentation of the epicondyle at the time of surgery and more complaints of hardware prominence leading to a second surgery to remove a deep implant. METHODS: A retrospective review was performed of patients treated surgically for displaced medial epicondyle fracture dislocations between 2008 and 2014. RESULTS: Sixteen patients with a total of 17 fracture dislocations were included in the study. The average follow-up was 11.5 months. Twelve fractures were treated with a screw and washer and 5 fractures were treated with a screw alone. All fractures healed. No fracture treated with a screw alone resulted in fragmentation or penetration of the epicondyle fragment. Seven of 12 patients treated with a screw and washer requested deep metal removal due to prominence and irritation at the medial epicondyle. No patient treated with a screw alone requested metal removal (58% vs. 0%; P=0.04). CONCLUSIONS: One author suggested that adding a washer to the screw for fixation of medial epicondyle fractures improved the ability to safely compress the fragment. However, the results of the present study report no case of fragmentation or penetration of the epicondyle when a washer was not used. In addition, the use of a screw and washer significantly increased the likelihood of a second surgery for removal of prominent hardware. LEVEL OF EVIDENCE: Level IV.

Effect of ulnar tunnel location on elbow stability in double-strand lateral collateral ligament reconstruction.

BACKGROUND: Double-strand lateral ulnar collateral ligament (LUCL) reconstruction is an effective treatment for posterolateral rotatory instability (PLRI) of the elbow, but anatomic landmarks for ulnar tunnel placement are often difficult to identify intraoperatively, which potentially can result in a nonanatomic LUCL reconstruction. This study investigated the effect of ulnar tunnel location on joint stability in double-strand LUCL reconstruction. METHODS: PLRI was artificially created in 7 cadaveric elbows, and double-strand LUCL reconstruction was performed. Five different ulnar tunnels were made along the length of the ulna. In each specimen, each possible pair of 2 tunnels (10 total) were used for graft passage. Varus and posterolateral joint gapping was measured after joint loading using a 3-dimensional digitizer system and X-ray image intensifier. RESULTS: No significant gapping was observed at the posterolateral ulnohumeral joint regardless of the location of the ulnar tunnels (P > .05). In contrast, the lateral radiocapitellar joint showed statistically significant varus gapping when both ulnar tunnels were placed proximal to the radial head-neck junction (P < .05). DISCUSSION: This findings of study suggest that the location of the ulnar tunnels may not be as critical as that of the humeral tunnel during double-strand LUCL reconstruction and that posterolateral rotatory elbow stability can be achieved reasonably well as long as at least 1 of the 2 ulnar tunnels is located at or distal to the radial head-neck junction level.

Management of Spinal Implants in Acute Pediatric Surgical Site Infections: A Multicenter Study.

STUDY DESIGN: A retrospective review of patients who underwent posterior spinal fusion (PSF) and returned within 90 days with an acute infection. OBJECTIVES: The study motive is to identify and understand the risk factors associated with failure of retaining spinal implants and failure to treat acute infection. BACKGROUND: The natural history of early surgical site infection (SSI) (less than 3 months) after PSF is not known and removing the implants early after PSF risks pseudarthrosis and deformity progression. METHODS: Patients ranging from 1999 to 2011 with surgical site infections (SSIs) who required irrigation and debridement within 3 months of PSF were identified from 4 institutions. Univariable and multivariable regression analysis were used to identify risk factors associated with failure of acute infection treatment. RESULTS: Eighty-two patients (59 female, 23 male) with a mean age of 13.6 years were identified. Median follow-up after initial surgery was 33 months (range: 12-112 months). Sixty-two (76%) were treated successfully with acute treatment and did not return with recurrent infection (cleared infection, group C); 20 (24%) returned later with chronic infection (recurrent infection, group R). Multivariable analysis indicated that patients with stainless steel implants (OR = 6.4, 95% CI = 1.7-32.1; p = .009) and older subjects (OR = 1.3, 95% CI = 1.0-1.6; p = .03) were more likely to present with recurrent infection. There was no difference between the groups with regard to the initial time of presentation post fusion, proportion of non-idiopathic diagnosis, rate of positive cultures, culture species, presence of fusion to pelvis, and time on antibiotic treatment. CONCLUSIONS: Seventy-six percent of patients presenting with an SSI less than 3 months after PSF did not require implant removal to clear their infection. Early postoperative SSIs can be treated with retention or implant exchange. Older patients and patients with stainless steel instrumentation are more likely to present with a late recurrent infection compared to other metals. LEVEL OF EVIDENCE: Level III.

The Effect of Closed Reduction of Small Finger Metacarpal Neck Fractures on the Ultimate Angular Deformity.

PURPOSE: To assess whether or not attempted closed reduction of fifth metacarpal neck fractures results in decreased fracture angulation at final follow-up. METHODS: Retrospective chart review of all patients aged 18 and older managed for isolated fifth metacarpal neck fractures between 2004 and 2014. RESULTS: Sixty-six patients managed for an isolated boxer fracture met inclusion criteria. Twenty-three patients underwent attempted reduction and 43 patients did not. Patients undergoing attempted reduction had a statistically significant improvement in fracture angulation following reduction compared with patients not undergoing attempted reduction. At final follow-up, there was no difference in fracture angle between the 2 groups. CONCLUSIONS: Closed reduction and splint immobilization of fifth metacarpal neck fractures was not an effective means of maintaining a significant improvement in fracture alignment upon healing. Other means, such as closed reduction with pin fixation or open reduction internal fixation, should be considered when maintenance of reduction is desired. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic III.

Best Practices in Intraoperative Neuromonitoring in Spine Deformity Surgery: Development of an Intraoperative Checklist to Optimize Response.

STUDY DESIGN: Consensus-based creation of a checklist and guideline. OBJECTIVE: To develop a consensus-based checklist to guide surgeon responses to intraoperative neuromonitoring (IONM) changes in patients with a stable spine and to develop a consensus-based best practice guideline for IONM practice in the United States. SUMMARY OF BACKGROUND DATA: Studies show that checklists enhance surgical team responses to crisis situations and improve patient outcomes. Currently, no widely accepted guidelines exist for the response to IONM changes in spine deformity surgery. METHODS: After a literature review of risk factors and recommendations for responding to IONM changes, 4 surveys were administered to 21 experienced spine surgeons and 1 neurologist experienced in IONM. Areas of equipoise were identified and the nominal group process was used to determine items to be included in the checklist. The authors reevaluated and modified the checklist at 3 face-to-face meetings over 12 months, including a period of clinical validation using a modified Delphi process. The group was also surveyed on current IONM practices at their institutions. This information and existing IONM position statements were used to create the IONM best practice guideline. RESULTS: Consensus was reached for the creation of 5 checklist headings containing 26 items to consider in the response to IONM changes. Consensus was reached on 5 statements for inclusion in the best practice guideline; the final guideline promotes a team approach and makes recommendations aimed at decreasing variability in neuromonitoring practices. CONCLUSIONS: The final products represent the consensus of a group of expert spine surgeons. The checklist includes the most important and high-yield items to consider when responding to IONM changes in patients with a stable spine, whereas the IONM guideline represents the group consensus on items that should be considered best practice among IONM teams with the appropriate resources.