ABSTRACT
The purpose of this article is to describe a technique to restore both vertical and horizontal stability using an augmentation of the acromioclavicular ligament complex (ACLC) and coracoclavicular (CC) ligaments with the combination of synthetic and biological support. Our technique introduces a modification in the surgical procedure for acromioclavicular (AC) joint dislocations; it provides the use of biological supplements not only during the repair of the CC ligaments but also when the ACLC is restored due to the use of a dermal patch as an augmentation allograft after the use of a horizontal cerclage. The main purpose of this technique is to replicate the anatomy and functionality of the native ligaments that stabilize the AC joint to improve both clinical and functional results.
ABSTRACT
PURPOSE: To evaluate the intra and interobserver reproducibility of a new system that assesses the three-dimensional humero-scapulo-thoracic kinematics using wearable technology in an outpatient setting. To obtain normative data with the system for scapular angular motions in three planes. METHODS: The SHoW Motion 3D kinematic tracking system is a motion analysis system that uses wireless wearable non-invasive inertial-magnetic sensors to assess the three-dimensional kinematics of the shoulder girdle. The sensors are placed over the skin in the sternum, scapular spine and arm to precisely define angular motions of the humerus and the scapula with three Degrees of Freedom (DOF) for each segment. The system was used to measure the scapular angular motions in three planes (upward/downward rotation, internal/external rotation and anterior/posterior tilt) during two shoulder full-range movements (flexion/extension and abduction/abduction) in both shoulders of 25 healthy volunteers (13 males and 12 females, mean age: 37 [standard deviation 11.1] years). In a first measuring session one examiner made two evaluations alternating with another examiner that made a third evaluation. In a second session, one week apart, the first examiner made a fourth evaluation. A mean curve was computed from the normalized data for each measurement to obtain normative data for scapular angular kinematics. Intra and inter-observer reproducibility was evaluated using Root Mean Square Error Estimation (RMSE) and Coefficients for Multiple Correlations (CMC). RESULTS: Both shoulders of the 25 volunteers were evaluated four times. The two hundred resulting kinematic analyses were pooled to get normative values for relations between humeral elevation angles and the three angular movements of the scapula. The system showed at least very good (CMC > 0.90) intra and inter-observer reproducibility for scapular tilt and upward-downward rotations both in flexion and abduction. For scapular internal-external rotation the results were acceptable (CMC > 0.75) but not as good, especially for the abduction movement. RMSE calculations showed consistently good reproducibility with RSME< 4° for all three angles evaluated in flexion and abduction. CONCLUSION: The SHoW Motion 3D kinematic tracking system is a quick, reproducible and easy to use system for the assessment of scapular angular kinematics in healthy adults. The data obtained is similar to that obtained with other validated methods. LEVEL OF EVIDENCE: Level II. CLINICAL RELEVANCE: The presented system is portable, easy to use and fast. It also has good intra and inter-observer reproducibility, making it a good tool to assess objectively scapular dyskinesis in the clinical setting. The normative data obtained is consistent with previous information available.
ABSTRACT
PURPOSE: To evaluate the 2-year results of an absorbable subacromial spacer in patients with irreparable posterosuperior rotator cuff tears. METHODS: Prospective longitudinal study of a consecutive case series of 16 subjects with irreparable tears of the posterosuperior rotator cuff in which the InSpace® subacromial spacer was arthroscopically implanted. A full clinical evaluation that included the Constant test, Simple Shoulder Test (SST) and the QuickDash questionnaire was performed preoperatively and at 12 and 24 months follow-up. The primary outcome for assessing the success of the procedure was a variable composed of a clinically relevant variation of the Constant (established in an improvement greater than 10 points) and the absence of surgical reintervention. RESULTS: Fifteen subjects (11 women/4 men, median age = 69.4 years [interquartile range 7.50], range 60-80 years) completed the 2-year of follow-up. According to the main evaluation criteria, only 6 patients (40%) had a successful outcome. Five subjects required reconversion to a reverse shoulder arthroplasty (at a median of 9.8 months postoperatively) due to absence of clinical improvement or worsening of symptoms. Of the ten remaining subjects, only 6 had improvements greater than 10 points in the Constant score. Despite of this, these 10 subjects had, on average, some improvement in the Constant test (preoperative Constant: median 35.0 [27.0-52.5] vs Constant at 24 months: 53.5 [55.0-84.0], significant differences p = 0.02), in the SST (3.0 [2.0-4.0] vs 6.0 [3.25-7.75], p = 0.039) and in the QuickDASH test (37.0 [33.25-40.0] vs 27.5 [20.5-32.75], p = 0.012). CONCLUSIONS: The outcomes of the implantation of the subacromial biodegradable spacer at 2-year follow-up are not satisfactory. In this small case series only 40% of patients seem to clearly benefit from surgery. One in three required revision to a reverse shoulder arthroplasty. The described technique does not seem a reasonable alternative for the management of the majority of patients with irreparable ruptures of the rotator cuff. The indications of this device should be more clearly defined. LEVEL OF EVIDENCE: IV.
