Radial Head Replacement for Acute Radial Head Fractures: Outcome and Survival of Three Implant Designs With and Without Cement Fixation

OBJECTIVES

To determine outcomes of radial head replacement (RHR) for acute fractures using 3 different implant designs with or without cement fixation.

DESIGN

Retrospective.

SETTING

Tertiary referral hospital.

PATIENTS/PARTICIPANTS

One hundred fourteen elbows underwent RHR for an acute radial head fracture using either (1) a nonanatomic design and smooth stem (n = 60), (2) a nonanatomic design with a grit-blasted, ingrowth, curved stem (n = 21), or (3) an anatomic design with a grit-blasted ingrowth straight stem (n = 33). Cemented (25%) or uncemented (75%) fixation was used at the discretion of the treating surgeon.

INTERVENTION

RHR.

MAIN OUTCOME MEASUREMENTS

The primary outcome was implant survivorship free of revision or removal for any reason. All elbows were evaluated clinically (the Mayo Elbow Performance Score and reoperations/complications) and radiographically.

RESULTS

Fourteen implants (12%) were revised. Of elbows with a minimum 2-year clinical follow-up, the average Mayo Elbow Performance Score was 88. The rate of survivorship free from revision was 92% [95% confidence interval (CI) = 87%-98%] at 2 years, 90% (CI = 84%-96%) at 5 years and 84% (CI = 75%-94%) at 10 years. The differences in survivorship between the 3 implants did not reach statistical significance, but the nonanatomic design with a grit-blasted ingrowth curved stem had a hazard ratio of 4.6 (95% CI = 0.9%-23%) for failure. There were no differences in survivorship between cemented versus uncemented stems. For those elbows with a minimum of 2 years of radiographic follow-up, implant tilt was observed in 10 (16%) elbows and loosening in 16 (26%) elbows. Stress shielding was present in 19 (42%) of well-fixed implants.

CONCLUSIONS

RHR for acute trauma leads to survivorship greater than 80% at 10 years. Radiographic changes (loosening, stress shielding, and implant tilting) can be expected in a substantial portion of elbows at long-term follow-up.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Radiological humeral adaptative changes five years after anatomical total shoulder arthroplasty using a standard-length cementless hydroxyapatite-coated humeral component

AIMS

The purpose of this study was to report bone adaptive changes after anatomical total shoulder arthroplasty (TSA) using a standard-length hydroxyapatite (HA)-coated humeral component, and to report on a computer-based analysis of radiographs to determine changes in peri-implant bone density objectively.

METHODS

A total of 44 TSAs, performed between 2011 and 2014 using a cementless standard-length humeral component proximally coated with HA, were included. There were 23 males and 21 females with a mean age of 65 years (17 to 65). All shoulders had good quality radiographs at six weeks and five years postoperatively. Three observers graded bone adaptive changes. All radiographs were uploaded into a commercially available photographic software program. The grey value density of humeral radiological areas was corrected to the grey value density of the humeral component and compared over time.

RESULTS

Stress shielding was graded as mild in 14 shoulders and moderate in three; the greater tuberosity was the predominant site for stress shielding. The mean metaphyseal and diaphyseal fill-fit ratios were 0.56 (SD 0.1) and 0.5 (SD 0.07), respectively. For shoulders with no radiologically visible stress shielding, the mean decrease in grey value in zones 1 and 7 was 20%, compared with 38% in shoulders with radiologically visible stress shielding.

CONCLUSION

The rate of moderate stress shielding was 7%, five years after implantation of a cementless standard-length HA-coated humeral component. Clinical observation of stress shielding identified on radiographs seems to represent a decrease in grey value of 25% or more. Cite this article: Bone Joint J 2021;103-B(5):958-963.

Is Allograft Reconstruction of the Medial Ulnar Collateral Ligament of the Elbow a Viable Option for Nonelite Athletes? Outcomes at a Mean of 8 Years

Background:

The rate of elbow medial ulnar collateral ligament (MUCL) injury and surgery continues to rise steadily. While authors have failed to reach a consensus on the optimal graft or anchor configuration for MUCL reconstruction, the vast majority of the literature is focused on the young, elite athlete population utilizing autograft. These studies may not be as applicable for the “weekend warrior” type of patient or for young kids playing on high school leagues or recreationally without the intent or aspiration to participate at an elite level.

Purpose:

To investigate the clinical outcomes and complication rates of MUCL reconstruction utilizing only allograft sources in nonelite athletes.

Study Design:

Case series; Level of evidence, 4.

Methods:

Patient records were retrospectively analyzed for individuals who underwent allograft MUCL reconstruction at a single institution between 2000 and 2016. A total of 25 patients met inclusion criteria as laborers or nonelite (not collegiate or professional) athletes with a minimum of 2 years of postoperative follow-up. A review of the medical records for the included patients was performed to determine survivorship free of reoperation, complications, and clinical outcomes with use of the Summary Outcome Determination (SOD) and Timmerman-Andrews scores. Statistical analysis included a Wilcoxon rank-sum test to compare continuous variables between groups with an alpha level set at .05 for significance. Subgroup analysis included comparing outcome scores based on the allograft type used.

Results:

Twenty-five patients met all inclusion and exclusion criteria. The mean time to follow-up was 91 months (range, 25-195 months), and the mean age at the time of surgery was 25 years (range, 12-65 years). There were no revision operations for recurrent instability. The mean SOD score was 9 (range, 5-10) at the most recent follow-up, and the Timmerman-Andrews scores averaged 97 (range, 80-100). Three patients underwent subsequent surgical procedures for ulnar neuropathy (n = 2) and contracture (n = 1), and 1 patient underwent surgical intervention for combined ulnar neuropathy and contracture.

Conclusion:

Allograft MUCL reconstruction in nonelite athletes demonstrates comparable functional scores with many previously reported autograft outcomes in elite athletes. These results may be informative for elbow surgeons who wish to avoid autograft morbidity in common laborers and nonelite athletes with MUCL incompetency.

Cost analysis and complication profile of primary shoulder arthroplasty at a high-volume institution

BACKGROUND

Paralleling the increased utilization of shoulder arthroplasty, bundled-payment reimbursement is becoming increasingly common. An understanding of the costs of each element of care and detailed information on the frequency of and reasons for readmission and reoperation are keys to developing bundled-payment initiatives. The purpose of this study was to perform a comprehensive analysis of complications, readmission rates, and costs of primary shoulder arthroplasty at a high-volume institution.

METHODS

Between 2012 and 2016, 2 shoulder surgeons from a single institution performed 1794 consecutive primary shoulder arthroplasties: 636 anatomic total shoulder arthroplasties (TSAs), 1081 reverse shoulder arthroplasties (RSAs), and 77 hemiarthroplasties. A cost analysis was designed to include a period of 60 days preoperatively, the index surgical hospitalization, and 90 days postoperatively, including costs of any readmission or reoperation.

RESULTS

The 90-day complication, reoperation, and readmission rates were 2.3%, 0.6%, and 1.8%, respectively. The 90-day readmission risk was higher among patients with an American Society of Anesthesiologists score of 3 or greater; a 1-unit increase in the American Society of Anesthesiologists score was associated with a $429 increase in index cost. Of the hospital readmissions, 10 were directly related to the index arthroplasty whereas 21 were not. The median standardized costs were as follows: preoperative evaluation, $481; index surgical hospitalization, $15,758; and postoperative care, $183. The median standardized costs for index surgical hospitalization were different for each procedure: TSA, $14,010; RSA, $16,741; and hemiarthroplasty, $12,709.

CONCLUSION

In this study, primary shoulder arthroplasty was associated with low 90-day reoperation and complication rates. The median standardized costs inclusive of preoperative workup and 90-day postoperative recovery were $14,675 and $17,407 for TSA and RSA, respectively.

The effect of radial head prosthesis diameter on posterolateral rotatory instability of the elbow

BACKGROUND

The purpose of this study is to investigate how different diameters of radial head replacement affect posterolateral translation with a valgus and supination force. We hypothesized that there would be less posterolateral rotatory translation with larger implant diameter.

METHODS

Eleven cadaveric arms were stressed at 30 and 60° of flexion with a consistent supination and valgus stress force under five conditions: native radial head, radial head excision, and with 3 sizes of radial head prosthesis. Displacement of the radial head posteriorly in relation to the capitellum on radiographs was measured. Displacement was expressed as a percentage relative to the average of the maximum and minimum native radial head diameters.

FINDINGS

The native radial heads had average minimum and maximum diameters of 23.3 mm and 25.2 mm, respectively. The angle of testing did not significantly change translation of the radial head. There was increased posterior translation relative to native head as the radial head sizes decreased from 24 mm to 20 mm and with excision of the radial head. Compared to the native head, the differences in displacement were statistically significant for the 20 mm radial head, but not for the 22 mm or 24 mm replacements. Radial head translation significantly increased after radial head excision.

INTERPRETATIONS

This cadaveric study illustrates that patients treated with radial head excision and radial head prosthesis with undersized diameters have increased posterior translation with a valgus and supination stress. The larger the radial head prosthesis (closer to native radial head), the more closely it approximated the amount of translation of the native radial head.

The effect of the beach-chair position angle on cerebral oxygenation during shoulder surgery

BACKGROUND

Although the safety of the beach-chair position (BCP) is widely accepted, rare devastating neurologic complications have been reported and attributed to cerebral hypoperfusion. Cerebral oxygenation (regional oxygen saturation [rSO₂]) can be monitored noninvasively using near-infrared spectroscopy. The purpose of this study was to determine the effect of BCP angle on cerebral oxygenation in patients undergoing shoulder surgery in the BCP.

METHODS

Fifty patients undergoing shoulder arthroscopy were prospectively enrolled to participate. Following induction of general anesthesia, each patient's rSO₂ was recorded at 0° of elevation and again at 30°, 45°, 60°, and 80° of elevation. Mean rSO₂ values and mean differences in rSO₂ were reported.

RESULTS

An average total decrease of 5% in rSO₂ was seen when comparing 0° with 80° (P < .001). There were statistically significant differences in rSO₂ values at beach-chair angles of 0° versus 30° (P <.001), 30° versus 45° (P = .007), and 45° versus 60° (P <.001) but not between 60° and 80° (P = .12). The decrease in rSO₂ was similar between each progressive increase in the beach-chair angle, leading to a linear decline in rSO₂ as the BCP increased (regression slope of -0.060%/°, P <.001). No patient's cerebral oxygenation dropped greater than 20% from baseline. Neither body mass index nor American Society of Anesthesiologists score had a significant impact on the relation of rSO₂ to BCP angle.

CONCLUSIONS

The average drop in rSO₂ is significantly less than the threshold of 20% used as an identifier for a cerebral deoxygenation event. This study illustrates the direct effect the BCP angle has on cerebral oxygenation.