George S. Athwal

Periprosthetic Humeral Fractures During Shoulder Arthroplasty

BACKGROUND Currently, there is little information available on the treatment and outcome of intraoperative periprosthetic humeral fractures that occur during shoulder arthroplasty. The purpose of this study was to report on the incidence, treatment, and outcome of, as well as the risk factors for, intraoperative periprosthetic humeral fractures. METHODS Between 1980 and 2002, forty-five intraoperative periprosthetic humeral fractures occurred during shoulder arthroplasty at our institution. Twenty-eight fractures occurred during primary total shoulder arthroplasty, three occurred during primary hemiarthroplasty, and fourteen occurred during revision arthroplasty. Nineteen fractures involved the greater tuberosity, sixteen involved the humeral shaft, six involved the metaphysis, three involved the greater tuberosity and the humeral shaft, and one involved both the greater and lesser tuberosities. All patients were followed for a minimum of two years. At the time of the latest follow-up, outcomes were assessed, radiographs were examined, and relative risks were calculated. RESULTS Over the twenty-two-year study period, the rate of intraoperative humeral fractures at our institution was 1.5%. All fractures healed at a mean of seventeen weeks. In the primary arthroplasty group (thirty-one patients), range of motion and pain scores improved significantly (p < 0.05) at the time of follow-up. In the revision arthroplasty group (fourteen patients), range of motion remained unchanged whereas pain scores improved significantly (p < 0.005). Transient nerve injuries occurred in six patients. Four fractures displaced postoperatively and were then treated nonoperatively; all four healed. Significant relative risks for intraoperative fracture were female sex, revision surgery, and press-fit implants (p < 0.05). CONCLUSIONS The data from the present study suggest that although intraoperative humeral fractures are associated with a high rate of healing, there was a substantial rate of associated complications, including transient nerve injuries and fracture displacement. Significant risk factors for intraoperative fractures include female sex, revision surgery, and press-fit humeral implants.

Terrible Triad Injury of the Elbow: Current Concepts

&NA; Fracture‐dislocations of the elbow remain among the most difficult injuries to manage. Historically, the combination of an elbow dislocation, a radial head fracture, and a coronoid process fracture has had a consistently poor outcome; for this reason, it is called the terrible triad. An elbow dislocation associated with a displaced fracture of the radial head and coronoid process almost always renders the elbow unstable, making surgical fixation necessary. The primary goal of surgical fixation is to stabilize the elbow to permit early motion. Recent literature has improved our understanding of elbow anatomy and biomechanics along with the pathoanatomy of this injury, thereby allowing the development of a systematic approach for treatment and rehabilitation. Advances in knowledge combined with improved implants and surgical techniques have contributed to better outcomes.

Radial Head Fractures—An Update

Radial head fractures are the most common fractures occurring around the elbow. Although radial head fractures can occur in isolation, associated fractures and ligament injuries are common. Assembling the clinical presentation, physical examination, and imaging into an effective treatment plan can be challenging. The characteristics of the radial head fracture influence the technique used to optimize the outcome. Fragment number, displacement, impaction, and bone quality are considered when deciding between early motion, fragment excision, and radial head excision, repair, or replacement. Isolated, minimally displaced fractures without evidence of mechanical block can be treated nonsurgically with early active range of motion (ROM). Partial, displaced radial head fractures without evidence of mechanical block can be treated either nonsurgically or with open reduction internal fixation (ORIF), as current evidence does not prove superiority of either strategy. For displaced fractures with greater than 3 fragments, radial head replacement is recommended. Radial head arthroplasty may be preferred over tenuous fracture fixation in the setting of associated ligament injuries when maintenance of joint stability could be compromised by ineffective fracture fixation.

Determination of Correct Implant Size in Radial Head Arthroplasty to Avoid Overlengthening

BACKGROUND Insertion of a radial head implant that results in radial overlengthening has been associated with altered elbow kinematics, increased radiocapitellar joint forces, capitellar erosions, early-onset arthritis, and loss of elbow flexion. The purpose of this study was to identify clinical and radiographic features that may be used to diagnose overlengthening of the radius intraoperatively and on postoperative radiographs. METHODS Radial head implants of varying thicknesses were inserted into seven cadaver specimens, which were then assessed clinically and radiographically. Eight stages were examined: the intact specimen (stage 1); repair of the lateral collateral ligament (stage 2); radial head resection with repair of the lateral collateral ligament (stage 3); insertion of an implant of the correct thickness (stage 4); and insertion of an implant that resulted in radial overlengthening of 2 mm (stage 5), 4 mm (stage 6), 6 mm (stage 7), or 8 mm (stage 8). The specimens were tested with and without muscle loading to simulate resting muscle tone and surgical paralysis, respectively. At each stage, radiographs were made to measure the ulnohumeral joint space and the lateral ulnohumeral joint was visually assessed. RESULTS We identified no difference, with regard to medial ulnohumeral joint incongruity as seen radiographically, among stages 1 through 6 during the tests with muscle loading. A significant difference in medial ulnohumeral joint incongruity was found in stages 7 (p = 0.003) and 8 (p < 0.001). The clinical (visually assessed) lateral ulnohumeral joint space gap was negligible in stages 1 through 4 but increased significantly at all stages involving overlengthening (gross gap, 0.9 mm with 2 mm of overlengthening [p = 0.005], 2.3 mm with 4 mm of overlengthening [p < 0.001], 3.4 mm with 6 mm [p < 0.001], and 4.7 mm with 8 mm [p < 0.001]). CONCLUSIONS Incongruity of the medial ulnohumeral joint becomes apparent radiographically only after overlengthening of the radius by >or=6 mm. Intraoperative visualization of a gap in the lateral ulnohumeral joint is a reliable indicator of overlengthening following the insertion of a radial head prosthesis.

Incidence of elbow dislocations in the United States population.

BACKGROUND There is minimal published information regarding the epidemiology of simple elbow dislocations. The purpose of this study was to report the estimated incidence of elbow dislocations in the United States, with use of the National Electronic Injury Surveillance System (NEISS) database. METHODS The NEISS database includes 102 hospitals representing a random sampling of all patients presenting to U.S. emergency departments. The database was queried for elbow dislocation events. NEISS data for 2002 through 2006 were used for raw data and weighted injury counts. Incidence rates with 95% confidence intervals (95% CI) were calculated by age group and sex, with use of U.S. census data. RESULTS One thousand and sixty-six elbow dislocations were identified, representing a weighted estimate of 36,751 acute dislocations nationwide. A calculated incidence of 5.21 dislocations per 100,000 person-years (95% CI, 4.74 to 5.68) was noted. The highest incidence of elbow dislocations (43.5%) occurred in those who were ten to nineteen years old (6.87 per 100,000 person-years; 95% CI, 5.97 to 7.76). The incidence rate ratio for the comparison of dislocations in males with those in females was 1.02 (5.26 per 100,000 for males and 5.16 per 100,000 for females). In patients ten years or older, 474 injuries (44.5% of total dislocations) were sustained in sports. Males dislocated elbows in football, wrestling, and basketball. Females sustained elbow dislocations most frequently in gymnastics and skating activities. CONCLUSIONS The estimated incidence of elbow dislocations in the U.S. population is 5.21 per 100,000 person-years, with use of a national database. Adolescent males are at highest risk for dislocation. Nearly half of acute elbow dislocations occurred in sports, with males at highest risk with football, and females at risk with gymnastics and skating activities.

Precontoured Parallel Plate Fixation of AO/OTA Type C Distal Humerus Fractures

Objectives: To determine the clinical effectiveness of precontoured parallel plating for the management of Orthopaedic Trauma Association (OTA) type C distal humerus fractures. Design: Retrospective case series. Setting: Level I trauma center. Patients/Participants: Between 2001 and 2005, 37 patients with OTA type C distal humerus fractures underwent open reduction and internal fixation exclusively with the Mayo Elbow Congruent Plating system. Thirty-two patients consented to participate in the study. Intervention: All patients underwent open reduction and internal fixation with a precontoured bicolumn parallel plating system. Main Outcome Measurements: Range of motion, Mayo Elbow Performance Score, Disabilities of the Arm, Shoulder and Hand score (DASH), complication rate, and radiographic evaluation. Results: At a mean of 27 months follow up, the mean arc of elbow flexion-extension motion was 97° (range, 10°-145°). The mean Mayo Elbow Performance Score was 82 points and the mean DASH score was 24 points. There were no implant failures and all distal humerus fractures healed. A total of 24 complications occurred in 17 patients (53%) with five patients (16%) having postoperative nerve injuries. Conclusions: Open reduction and internal fixation with a precontoured parallel plating system is an effective treatment method for OTA type C distal humerus fractures. Despite this, the fact that over half of the patients had a significant complication will require utmost vigilance on the part of the surgeon to avoid intraoperative complications. Patient counseling is paramount.

Evidence-Based Indications for Elbow Arthroscopy

PURPOSE The purpose was to review the literature on the outcomes of elbow arthroscopy and to make evidence-based recommendations for or against elbow arthroscopy for the treatment of various conditions. Our hypothesis was that the evidence would support the use of elbow arthroscopy in the management of common elbow conditions. METHODS A literature search was performed by use of the PubMed database in October 2010. All therapeutic studies investigating the results of treatment with elbow arthroscopy were analyzed for outcomes and complications. The literature specific to common elbow arthroscopy indications was summarized and was assigned a grade of recommendation based on the available evidence. RESULTS There is fair-quality evidence for elbow arthroscopy in the treatment of rheumatoid arthritis of the elbow and lateral epicondylitis (grade B recommendation). There is poor-quality evidence for, rather than against, the arthroscopic treatment of degenerative arthritis, osteochondritis dissecans, radial head resection, loose bodies, post-traumatic arthrofibrosis, posteromedial impingement, excision of a plica, and fractures of the capitellum, coronoid process, and radial head (grade C(f) recommendation). There is insufficient evidence to give a recommendation for or against the arthroscopic treatment of posterolateral rotatory instability and septic arthritis (grade I recommendation). CONCLUSIONS The available evidence supports the use of elbow arthroscopy in the management of the majority of conditions where it is currently used. The quality of the evidence, however, is generally fair to poor. LEVEL OF EVIDENCE Level IV, systematic review of Level II-IV studies.

Current Recommendations for the Treatment of Radial Head Fractures

Radial head fractures are the most common type of elbow fractures. Although a consensus has emerged that favors the nonsurgical treatment of undisplaced fractures, controversy surrounds the treatment of displaced radial head fractures. Further research is necessary to provide a better scientific rationale for making treatment recommendations. Options for the treatment of displaced fractures include nonoperative management, fragment excision, whole head excision, open reduction and internal fixation, and radial head arthroplasty. The purpose of this article is to review the mechanisms that result in radial head fracture, to describe important physical findings that assist in identifying injuries associated with radial head fractures, and to define the role of the various interventions described for the treatment of radial head fractures.

Pain relief and functional results after resection arthroplasty of the shoulder

We have examined the relief from pain and the functional outcome in 18 patients who underwent resection arthroplasty of the shoulder as a salvage operation between 1988 and 2002. The indications included failed shoulder replacement in 17, with infection in 13, and chronic septic arthritis in one. The mean follow-up was 8.3 years (2.5 to 16.6). Two intra-operative fractures of the humerus occurred, both of which healed. The level of pain was significantly decreased (t-test, p < 0.001) but five patients continued to have moderate to severe pain. The mean active elevation was 70 degrees (0 degrees to 150 degrees ) postoperatively and represented an improvement from 39 degrees (0 degrees to 140 degrees ) (t-test, p = 0.003), but internal and external rotation were hardly changed. The mean number of positive answers on the 12-question Simple Shoulder Test was 3.1 (0 to 12) but the shoulder was generally comfortable when the arm was positioned at rest by the side. The mean post-operative American Shoulder and Elbow Surgeons score was 36 (8 to 73). Despite applying this procedure principally to failed shoulder replacements, the results were similar to those reported in the literature for patients after severe fracture-dislocation. Reduction of pain is possible in one half to two-thirds of patients. The outcome of this operation in providing relief from pain cannot be guaranteed, but the shoulder is usually comfortable at rest, albeit with profound functional limitations.

Moderate to large engaging Hill-Sachs defects: an in vitro biomechanical comparison of the remplissage procedure, allograft humeral head reconstruction, and partial resurfacing arthroplasty

BACKGROUND The management of engaging Hill-Sachs defects (HSD) is controversial. The purpose of this study was to biomechanically compare 3 treatment strategies. MATERIALS AND METHODS Eight specimens were tested on a shoulder simulator. The protocol involved testing 2 unrepaired HSD (30% and 45%), which were then treated with remplissage, humeral head allograft (HHA), and partial resurfacing arthroplasty (PRA). Stability (defect engagement and glenohumeral stiffness) and range of motion (ROM) were measured. RESULTS All 30% and 45% HSDs engaged and dislocated. Remplissage and HHA effectively prevented engagement in all specimens; however, 62% of PRA engaged. No repair exhibited stiffness significantly greater than intact, but 30% and 45% remplissage produced a 74% and 207% increase, respectively, and were significantly greater than the unrepaired states (P ≤ .047). Stiffness results for HHA and PRA closely matched those of intact. In adduction, remplissage reduced internal-external ROM compared with both defects (P ≤ .01), but only 30% remplissage caused a significant decrease compared with intact (P = .049). In abduction, all repairs reduced ROM compared with HSD (P ≤ .04), but none compared with intact (P ≥ 0.05). In extension, remplissage had significantly less ROM than either HHA or PRA (P ≤ .02). CONCLUSION All procedures improved stability; however, unlike remplissage, results from HHA and PRA closely resembled intact. Remplissage (30% and 45%) improved stability and eliminated engagement but caused reductions in ROM. HHA and PRA re-established intact ROM, but PRA could not fully prevent engagement. The effects of each technique are not equivalent and further studies are required.