ABSTRACT: Knowledge of the factors affecting the prognosis for improvement in function and comfort with time after shoulder arthroplasty is important to clinical decision-making. This study sought to identify some of these factors in 176 consecutive patients undergoing the ream-and-run procedure.
The time course for improvement in patient function and comfort was determined for the entire group as well as for subsets by sex, age, diagnosis, preoperative function, and surgery date. Patients having repeat surgery were analyzed in detail.
Shoulder comfort and function increased progressively after the ream-and-run procedure, reaching a steady state by approximately twenty months. The shoulders in 124 patients with at least two years of follow-up were improved by a minimal clinically important difference. The shoulders in sixteen patients with at least two years of follow-up were not improved by the minimal clinically important difference. Twenty-two patients had repeat procedures, but only seven had revision to a total shoulder arthroplasty. Fourteen patients did not have either a known revision arthroplasty or two years of follow-up. The best prognosis was for male patients over the age of sixty years, with primary osteoarthritis, no prior surgical procedures, a preoperative score on the simple shoulder test of ≥5 points, and surgery after 2004. Repeat surgical procedures were more common in patients who had a greater number of surgical procedures before the ream-and-run surgery.
This study is unique in that it characterizes the factors affecting the time course for improvement in shoulder comfort and function after a ream-and-run procedure. Improvement occurs after this procedure for at least 1.5 years. This procedure appears to be best suited for an older male patient with reasonable preoperative shoulder function without prior shoulder surgery.
Prognostic Level II. See Instructions for authors for a complete description of levels of evidence.
The Journal of Bone and Joint Surgery 07/2012; 94(14):e102. · 3.27 Impact Factor
ABSTRACT: Glenoid erosion and medial migration of the humeral head prosthesis have been observed after most types of shoulder arthroplasty. A method of measuring the change in humeral head position with time after shoulder prosthetic arthroplasty was applied it to 14 shoulders that underwent humeral hemiarthroplasty with concentric glenoid reaming. We hypothesized that the measurement technique would be reproducible and that the rate of wear would be small in the series of shoulders studied.
Standardized anteroposterior and axillary radiographs were obtained after surgery. Two examiners measured the position of the humeral head center in relation to scapular reference coordinates for the anteroposterior and axillary projections and plotted these values against time after surgery. The change in position was characterized as the slope of this plot. Shoulders were included if there were at least 3 sets of postoperative films, the last being at least 2 years after surgery.
The slopes measured by the 2 examiners agreed within 0.5 mm/y for the anteroposterior and the axillary projections. For the series of shoulder arthroplasties, the rate of movement of the head center toward the scapula was less than 0.4 mm/y for either examiner in either projection.
Medial migration is a concern after any type of shoulder arthroplasty, whether a hemiarthroplasty, a biological interpositional arthroplasty, or a total shoulder arthroplasty. Quantifying the rate of medial migration over time after shoulder arthroplasty is an important element of clinical follow-up.
This is an inexpensive, practical, and reproducible method that can be used to determine the rate of medial migration of the humeral head on plain radiographs after shoulder arthroplasty. The average rate of medial migration in the shoulders in this study was small.
Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.] 03/2011; 20(2):301-7. · 1.93 Impact Factor
ABSTRACT: Recent articles in this journal showed the clinical importance of the position of the humeral head center in relation to the glenoid. However, the precision, reproducibility, and sensitivity of this and other methods of documenting the head center position have not been evaluated in detail.
We used templates to fit a coordinate system to the scapular anatomy visible on standardized radiographs. Two observers then used these templates to measure the position of the head center relative to this coordinate system on 25 normal shoulder radiographs and on 25 radiographs of shoulders with cuff tear arthropathy (CTA).
Head center measurements had excellent precision. Normal shoulder radiographs showed a consistent head center position (0.7 ± 1.7 mm medial and 0.6 ± 1.3 mm inferior to the coordinate origin on the anteroposterior view and 0.1 ± 1.3 mm medial and 0.0 ± 1.3 mm anterior to the coordinate origin on the axillary view). The head center of CTA shoulder radiographs was 10.18 ± 5.16 mm above the coordinate origin on the anteroposterior view, significantly different from that for the normal shoulder radiographs (P < .001).
The relative position of the humeral head center to the scapula determines the resting length and the moment arms of the scapulohumeral muscles. Correlation of shoulder function with the head center position may provide insights into both shoulder pathomechanics and the optimization of shoulder arthroplasty.
This practical technique showed a high degree of precision and reproducibility for normal and CTA shoulder radiographs as well as a high level of discrimination between these two groups.
Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.] 10/2010; 20(3):363-71. · 1.93 Impact Factor