Lynn A. Crosby

Closed treatment of displaced middle-third fractures of the clavicle gives poor results

We evaluated 242 consecutive fractures of the clavicle in adults which had been treated conservatively. Of these, 66 (27%) were originally in the middle third of the clavicle and had been completely displaced. We reviewed 52 of these patients at a mean of 38 months after injury. Eight of the 52 fractures (15%) had developed nonunion, and 16 patients (31%) reported unsatisfactory results. Thirteen patients had mild to moderate residual pain and 15 had some evidence of brachial plexus irritation. Of the 28 who had cosmetic complaints, only 11 considered accepting corrective surgery. No patient had significant impairment of range of movement or shoulder strength as a result of the injury. We found that initial shortening at the fracture of ≥20 mm had a highly significant association with nonunion (p Final shortening of 20 mm or more was associated with an unsatisfactory result, but not with nonunion. No other patient variable, treatment factor, or fracture characteristic had a significant effect on outcome. We now recommend open reduction and internal fixation of severely displaced fractures of the middle third of the clavicle in adult patients.

An evaluation of the relationships between reverse shoulder design parameters and range of motion, impingement, and stability

BACKGROUND The purpose of this study was to evaluate the role of reverse shoulder design parameters on performance. METHODS A computer analysis was conducted on the Grammont reverse shoulder to quantify the effect of varying design parameters on functional measurements during humeral abduction/adduction. To demonstrate the application of these relationships, a novel prosthesis was designed. RESULTS The Grammont reverse shoulder impinged inferiorly and superiorly on the glenoid at 31 degrees and 95 degrees of humeral abduction with an average jump distance of 10 mm. Several linear relationships were identified. The proposed 38 mm, 42 mm, and 46 mm reverse shoulder designs impinged inferiorly and superiorly on the glenoid at 7.3 degrees/87.5 degrees, 1 degrees/87.5 degrees, and 0 degrees/89.3 degrees of humeral abduction with an average jump distance of 11.7 mm, 13.5 mm, and 14.1 mm, respectively. CONCLUSIONS The results of this study demonstrate that subtle changes in design parameters can minimize inferior glenoid impingement and offer potential for dramatic functional improvements in ROM (39%) and jump distance (36%).

Partial-thickness rotator cuff tears

Our understanding of the spectrum of rotator cuff disease continues to improve as imaging modalities and treatment techniques become more refined. The original ideas and contributions provided by Codman and Neer continue to inform our understanding. Unfortunately, high-quality data on the management of partial-thickness rotator cuff tears are relatively lacking in the literature when compared with those available on full-thickness tears. This is particularly important because the estimated prevalence of partialthickness rotator cuff tears is significant and can be expected to increase in light of our aging population and the association between increasing age and rotator cuff pathology. There remains a lack of long-term outcome studies; however, short-term follow-up studies provide us with important information regarding the difference between bursaland articular-sided partial-thickness tears. Our overall understanding of the anatomy, biomechanics, and potential etiologies of partial-thickness tears continues to improve.

Treatment of glenohumeral sepsis with a commercially produced antibiotic-impregnated cement spacer.

BACKGROUND We report our experience in treating infected shoulder arthroplasty and primary shoulder sepsis using a commercially produced antibiotic-impregnated cement spacer. MATERIALS AND METHODS We treated 16 shoulders in 15 patients for infected arthroplasty or osteomyelitis of the proximal humerus with irrigation and débridement, hardware removal, or humeral head resection, or both, and placement of an interval articulating hemiarthroplasty with a commercially made gentamicin-impregnated cement spacer. RESULTS Mean follow-up was 20.5 months after spacer placement. At the time of débridement, 12 shoulders had positive cultures; the most common organisms were methicillin-resistant Staphylococcus aureus (n = 3) and S. epidermidis (n = 3). Twelve patients underwent revision. Four refused revision and have retained antibiotic spacers. White blood cell counts returned to within normal ranges in all patients at the time of revision, the erythrocyte sedimentation rate in 5 of 12 patients, C-reactive protein in 8 of 12 patients, and interleukin-6 in 9 of 11 patients. Mean visual analog pain scale score decreased from 8.4 before spacer placement to 0.5 at the final follow-up. Active forward flexion increased from a mean of 65 degrees to 110 degrees , and active external rotation from -5 degrees to 20 degrees . Mean University of California Los Angeles (UCLA) Shoulder Rating Scale score increased from 7 to 26, Simple Shoulder Test (SST) from 1.2 to 6.6, American Shoulder and Elbow Surgeons (ASES) Standardized Shoulder Assessment Form score from 16 to 74, and Constant score from 16 to 57. There was no recurrence of infection. CONCLUSIONS Treatment of glenohumeral sepsis with a commercially produced antibiotic-impregnated cement spacer appears to be an effective treatment modality, and serum interleukin-6 level appears to be useful in the evaluation of shoulder infection.

Follow-up on Misrepresentation of Research Activity by Orthopaedic Residency Applicants: Has Anything Changed?

BACKGROUND In our previous study, published in 1999, we showed that 18% of research citations listed as published by orthopaedic residency applicants were misrepresented. Since our last report, we sought to determine whether there had been any change in the behavior of applicants wishing to pursue the field of orthopaedic surgery. METHODS We evaluated the research citations that were identified after a review of the Publications section of the Common Application Form from the Electronic Residency Application Service for all applicants to our orthopaedic residency program for 2005 and 2006. Inclusion and exclusion criteria were established for citations listed on candidate applications. Citations were required to be from journals listed in Ulrichs Periodicals Directory. The PubMed-MEDLINE database engine was used to search for citations. If searching failed to yield the cited publication, a review of the journal of alleged publication was undertaken and an interlibrary search was conducted with the use of several research databases. When no match was found, the citation was labeled as misrepresented. Misrepresentation was defined as either (1) nonauthorship of an existing article or (2) claimed authorship of a nonexistent article. RESULTS One hundred and forty-two (35.9%) of 396 applicants during the 2005 and 2006 application periods listed publications. A total of 304 citations were claimed from these 142 applicants. Listings included articles that were in press or in print (thirty-four citations), articles in journals not found in Ulrichs Periodicals Directory (twenty-eight citations), book chapters (twenty-three citations), and articles recorded as having been submitted (eighty-eight citations). These 173 works were excluded from our analysis. One hundred and thirty-one citations were referenced as appearing in journals per our search criteria, and all were verified. Twenty-seven or 20.6% (95% confidence interval, 14.2% to 28.7%) of 131 citations were misrepresented. CONCLUSIONS The prevalence of misrepresented research publications from orthopaedic surgery residency applicants increased modestly to 20.6% compared with that found in our original report (18%). As we recommended in our last report, we strongly urge residency programs to require applicants to submit reprints of their publications with their residency applications. Perhaps standardized guidelines should be developed to help to prevent misrepresentation through the Electronic Residency Application Service.

Fatty Infiltration Does Not Progress After Rotator Cuff Repair in a Rabbit Model

PURPOSE The purpose of this study is to evaluate the changes in fatty infiltration of the rotator cuff after it is repaired. METHODS The supraspinatus muscle was unilaterally detached from the greater tuberosity in 15 New Zealand white rabbits. Six weeks after muscle detachment, 5 rabbits were killed to halt the process of fatty infiltration and 10 rabbits underwent primary repair of the rotator cuff. Six months after repair, the remaining 10 rabbits were killed, and the muscle specimens were examined microscopically to evaluate the muscle with respect to fatty infiltration. RESULTS Fatty infiltration was evident 6 weeks after detachment of the supraspinatus tendon (P = .0012, analysis of variance). This infiltration was greatest at the musculotendinous junction (P = .0005) and decreased toward the muscle origin (P = .29). Six months after repair of the supraspinatus, there was no progression of fatty infiltration in the repaired muscle as compared with the controls (P = .3). CONCLUSIONS Fatty infiltration of the rotator cuff in this animal model occurs as early as 6 weeks after a rotator cuff tear. After repair of the rotator cuff, the process of fatty infiltration does not progress any further. The changes that take place in this rabbit model in the first 6 weeks after a rotator cuff tear appear to be irreversible even with successful rotator cuff repair. CLINICAL RELEVANCE The presence of fatty infiltration of a torn rotator cuff does not preclude a successful repair. The repair can prevent further progression and atrophy of the rotator cuff, but the changes that appear in the muscle as early as 6 weeks after a rotator cuff tear appear to be irreversible.

Predicting transfusion in shoulder arthroplasty

BACKGROUND This study was conducted to evaluate the incidence of transfusion in shoulder arthroplasty, determine clinical factors associated with increased risk for transfusion, and develop an algorithm to assist the surgeon in preoperative planning with regards to blood management. MATERIAL AND METHODS The study had 2 phases: (1) development of a clinical prediction rule for transfusion using 280 procedures and (2) a validation study of the algorithm applied to 109 new patients. Phase 1 consisted of a retrospective record review of 280 consecutive shoulder arthroplasties to determine risk factors for transfusion. Phase 1 also identified a preoperative hemoglobin level of less than 12.5 g/dL as predictive of the need for blood transfusion. This cutoff was prospectively applied to 109 patients undergoing shoulder arthroplasty in phase 2. RESULTS The transfusion rate for phase 1 was 19.6%. Preoperative hemoglobin level (P < .001), age (P= .003), and the number of comorbid conditions (P = .005) were statistically significant risk factors. Patients with a preoperative hemoglobin level of less than 12.5 g/dL have a 4-fold increased risk of requiring a blood transfusion. In phase 2, the cutoff of less than 12.5 g/dL yielded a sensitivity of 88%, specificity of 78%, and positive and negative likelihood ratios of 4.0 and 0.15, respectively. CONCLUSION Preoperative hemoglobin level, age, and number of comorbid conditions are all predictive of transfusion in shoulder arthroplasty. Tailoring blood ordering based on a preoperative hemoglobin level of 12.5 g/dL is safe and effective. LEVEL OF EVIDENCE Prognostic study, level 2.

Functional and radiographic long-term outcomes of hemiarthroplasty for proximal humeral fractures

BACKGROUND Hemiarthroplasty is the preferred surgical procedure for 3- and 4-part proximal humeral fractures. Our retrospective study examined functional and radiographic outcomes at 2- and 5-year follow-up in patients who received a hemiarthroplasty for 3- and 4-part proximal humeral fractures. MATERIALS AND METHODS Forty-seven consecutive patients of a single surgeon treated with a cemented shoulder hemiarthroplasty between 2000 and 2006 were followed up. Standard surgical technique was used in all cases. Postoperative radiographs were compared with radiographs at 2 and 5 years along with active range of motion and functional outcomes scores. RESULTS Twenty-five patients were examined at 2 years and twenty-two at 2 and 5 years. The mean age was 61 years. The mean acromiohumeral distance decreased from 10.3 mm postoperatively to 8.5 mm at 2 years and 6.7 mm at 5 years (P ≤ .001). More patients had stem osteolysis and tuberosity reabsorption at 2 and 5 years compared with postoperatively (P = .016 and P ≤ .001, respectively). The University of California, Los Angeles score decreased from 26.0 to 22.3 (P = .045); the Constant score decreased from 61.1 to 50.1 (P = .01); the Simple Shoulder Test 12 score decreased from 7.7 to 6.2 (P = .018); and the American Shoulder and Elbow Surgeons score decreased from 70.4 to 58.8 (P = .015). Pain scores increased from 2- to 5-year follow-up (P = .018). The range-of-motion measures changed little from the 2-to 5-year follow-up. CONCLUSIONS Hemiarthroplasty has a high rate of long-term complications. Increases in acromiohumeral distance, stem osteolysis, and tuberosity reabsorption were observed between 2- and 5-year follow-up. Pain scores and functional outcomes worsened. No improvement in range of motion was observed.

Biomechanical evaluation of a pre-contoured clavicle plate

Recent attention has been focused on the operative treatment of mid-shaft fractures of the clavicle. This study compares the in-vitro biomechanical properties of a pre-formed titanium clavicle plate (Acumed) to a Synthes 3.5 mm limited-contact dynamic-compression (LCDC) plate using a cadaveric osteotomy model. An osteotomy was performed on 7 pairs of human clavicles and were randomly plated with either a Synthes 3.5 mm LCDC stainless steel plate or an Acumed titanium pre-contoured clavicle plate. After plating, specimens were tested on an EnduraTEC material testing apparatus for axial compression and tension strength, as well as torsional strength in compression and tension. Biomechanical test results for plated specimens are reported for the LCDC plate and the Acumed plate, and the 2 plates are compared. This exploratory study supports investigations with larger sample sizes to determine if the Acumed pre-contoured plate differs from the LCDC plate in biomechanical properties and the clinical implications of such differences.

Infection after primary anatomic versus primary reverse total shoulder arthroplasty.

BACKGROUND Deep periprosthetic infection is a serious complication after total shoulder arthroplasty (TSA) and is associated with suboptimal clinical results. This retrospective study aimed to determine whether a difference in infection rate existed after primary anatomic TSA (aTSA) and primary reverse TSA (rTSA). METHODS A TSA database was retrospectively reviewed to identify primary TSAs performed from 2004 to 2012 and isolate cases of confirmed deep periprosthetic infection. Data collected included age, sex, preoperative diagnosis, previous nonarthroplasty operative history, implant type, and infecting organism. RESULTS From 814 primary TSAs performed, deep periprosthetic infections were confirmed in 16 shoulders. Infections occurred in 6 aTSAs and 10 rTSAs, with no significant difference among the prosthesis types. Pathogens included Staphylococcus spp, Propionibacterium acnes, and Escherichia coli. In the subgroup of shoulders with no previous operations, no significant difference in infection rate was found among the prosthesis types. Shoulders with previous nonarthroplasty operations undergoing primary TSA exhibited a significantly higher (P = .016) infection rate compared with shoulders with no operative history. Both aTSA and rTSA performed in previously operated-on shoulders demonstrated higher infection rates compared with shoulders with no prior operative intervention. The infection rate was significantly higher (P = .016) in the rTSA group. CONCLUSIONS There is no difference in infection rate after primary aTSA and primary rTSA in shoulders that have not undergone previous operative interventions. Infection is more likely to develop in shoulders undergoing primary rTSA that have had one or more nonarthroplasty operative procedures.