Olivier Verborgt

Capitellar erosion caused by a metal radial head prosthesis. A case report.

The long-term results of resection of the radial head for the treatment of a simple radial head fracture have been generally satisfactory1-5. However, some late complications, such as proximal migration of the radius, can disable the patient and are difficult to treat. Proximal migration of the radius is usually asymptomatic3-5, although wrist pain develops in a minority of patients3-8. The options for treatment are limited, and clinical studies have shown poor and unreliable results9,10. Sowa et al. described a case in which a silicone radial head prosthesis was implanted for the treatment of wrist symptoms10. Proximal migration of the radius progressed, and it was concluded that a more rigid implant would be necessary. Sellman et al. reached a similar conclusion after performing a biomechanical study of this problem11. We report the case of a patient who had early progressive erosion of the capitellum after the insertion of a metal radial head prosthesis for the treatment of wrist pain following radial head resection after trauma. This complication has not been reported previously, to our knowledge. Our patient was informed that data concerning the case would be submitted for …

Accuracy of placement of the glenoid component in reversed shoulder arthroplasty with and without navigation

HYPOTHESIS Navigation can improve accuracy of placement of the glenoid component in reversed shoulder arthroplasty. MATERIAL AND METHODS A glenoid component of a reversed shoulder prosthesis was implanted in 14 paired scapulohumeral cadaver specimens. Seven procedures with standard instrumentation were compared with 7 procedures using navigation. The intraoperative goal was to place the component centrally in the glenoid in the axial plane and 10° inferiorly tilted in the frontal plane. Glenoid component version and tilt and screw placement were studied using CT scan and macroscopic dissection. RESULTS The mean version of the glenoid component in the standard instrumentation group was 8.7° of anteversion, compared with 3.1° of anteversion in the navigated group. The mean tilt of the glenoid component was 0.9° in the standard group and 5.4° of inferior tilt in the navigated group. Using navigation, the range of error for version was 8° (SD 3.3°) compared to 12° (SD 4.1°) in controls. For tilt, the range of error was 8° (SD 3.6°) in navigated specimens and 16° (SD 6.0°) for controls. In the control group, there were no perforations of the central peg, but 1 inferior screw and 4 superior screws were malpositioned. In the navigation group, no central peg perforated, all inferior screws were correctly positioned, and 2 superior screws were malpositioned. CONCLUSION Computer navigation was more accurate and more precise than standard instrumentation in its placement of the glenoid component in reversed shoulder arthroplasty.

Long-term outcomes after deltoid muscular flap transfer for irreparable rotator cuff tears

We reviewed 20 cases (18 patients) with massive, irreparable rotator cuff tears that were treated with a deltoid flap transfer. The mean follow-up was 13.9 years. The mean absolute Constant score increased from 49.1 points preoperatively to 71.9 points at the last follow-up (P < .001). Pain scores improved from 5.3 to 13.8 points, regardless of the state of the deltoid flap (P < .001), and the scores for activities of daily living increased from 8.6 to 17 points (P < .001). The mean muscular strength improved from 4.4 points preoperatively to 7.6 points at the last follow-up (P = .009), and 16 patients (80%) had a positive test for supraspinatus strength. Deltoid flaps were completely ruptured in 3 cases in the short term and 10 cases at later follow-up; the mean thickness of nonruptured deltoid flaps was 4.2 mm. The mean acromiohumeral distance decreased from 6.95 mm preoperatively to 3.05 mm postoperatively (P < .00001). Osteoarthritis rates increased from stage 0.6 to stage 2.0 by the classification of Samilson and Prieto (P < .0001). This study shows that the results of a deltoid flap transfer over short- or medium-term follow-up were satisfactory for individuals who wished to return to work or for pain relief, with an improvement in the total function of the shoulder. However, the long-term outcomes were poor; deltoid flaps were ruptured in 10 shoulders (50%), and stage 2 or 3 osteoarthritis occurred in 14 shoulders (70%). Therefore, we do not recommend further use of this procedure in the treatment of massive, irreparable rotator cuff tears.

Patient-specific instrument guidance of glenoid component implantation reduces inclination variability in total and reverse shoulder arthroplasty

BACKGROUND The aim of this study was to assess the influence of 3-dimensional (3D) preoperative planning and patient-specific instrument (PSI) guidance of glenoid component positioning on its inclination in total shoulder arthroplasty (TSA) and reverse shoulder arthroplasty (RSA). MATERIALS AND METHODS Thirty-six shoulder arthroplasties (12 TSAs, 24 RSAs) were analyzed, of which 18 procedures (6 TSAs, 12 RSAs) were executed using preoperative 3D planning and patient-specific guides to position the central guide pin for glenoid component implantation. In 9 cases, the glenoid anatomy was severely distorted through wear or previous surgery. The inclination of the glenoid component was measured by 2 observers, using the angle between the glenoid baseplate and the floor of the supraspinatus fossa (angle β) on postoperative radiographs. RESULTS For TSA, the average angle β was 74 ± 9 in the PSI group and 86 ± 12 in the non-PSI group; for RSA, the average angle β was 83 ± 7 in the PSI group and 90 ± 17 in the non-PSI group. Extreme angles β, which represent extreme values of glenoid component inclination, are more likely to occur in the non-PSI group than in the PSI group (P < .001 for TSA; P = .02 for RSA). CONCLUSIONS The3D preoperative surgical planning and PSI guidance reduce variability in glenoid component inclination and avoid extreme inclination errors for TSA and RSA.

Computer navigation and patient-specific instrumentation in shoulder arthroplasty.

Longevity of total anatomic and reversed shoulder arthroplasty largely depends on accurate correction of glenoid deformity and correct positioning and fixation of the glenoid component. However, the morphology of the scapula is inconsistent, varying degrees of osteoarthritis cause numerous anatomic changes, and standard 2-dimensional imaging and standard surgical instrumentation are imprecise for preoperative planning and execution of glenoid reconstruction. Recently, various authors have shown that preoperative 3-dimensional surgical planning and computer navigation technology may increase the accuracy and repeatability of the implantation of the glenoid component, especially for the position and orientation of the glenosphere and screws in reversed arthroplasty. These novel techniques may allow the surgeon to better define the preoperative deformity, select the optimal implant position, and then accurately execute the plan at the time of surgery. Future studies are needed to determine the long-term effect on functional outcome and cost-effectiveness of computer-assisted technology in shoulder arthroplasty.

Iliac Bone Grafting of the Intact Glenoid Improves Shoulder Stability with Optimal Graft Positioning

BACKGROUND Bone grafting procedures are increasingly popular for the treatment of anterior shoulder instability. In patients with a high risk of recurrence, open coracoid transplantation is preferred but can be technically demanding. Free bone graft glenoid augmentation may be an alternative strategy for high-risk patients without significant glenoid bone loss. This biomechanical cadaveric study assessed the stabilizing effect of free iliac crest bone grafting of the intact glenoid and the importance of sagittal graft position. METHODS Eight fresh frozen cadaveric shoulders were tested. The bone graft was fixed on the glenoid neck at 3 sagittal positions (50%, 75%, and 100% below the glenoid equator). Displacement and reaction force were monitored with a custom device while translating the humeral head over the glenoid surface in both anterior and anteroinferior direction. RESULTS Peak force (PF) increased significantly from the standard labral repair to the grafted conditions in both anterior (14.7 ± 5.5 N vs 27.3 ± 6.9 N) and anteroinferior translation (22.0 ± 5.3 N vs 29.3 ± 6.9 N). PF was significantly higher for the grafts at the 50% and 75% positions compared with the grafts 100% below the equator with anterior translation. Anteroinferior translation resulted in significantly higher values for the 100% and 75% positions compared with the 50% position. CONCLUSIONS This biomechanical study confirms improved anterior glenohumeral stability after iliac crest bone graft augmentation of the anterior glenoid. The results also demonstrate the importance of bone graft position in the sagittal plane, with the ideal position determined by the direction of dislocation.

Efficacy of Different Types of Mobilization Techniques in Patients With Primary Adhesive Capsulitis of the Shoulder: A Systematic Review

OBJECTIVE To systematically review the literature for efficacy of isolated articular mobilization techniques in patients with primary adhesive capsulitis (AC) of the shoulder. DATA SOURCES PubMed and Web of Science were searched for relevant studies published before November 2014. Additional references were identified by manual screening of the reference lists. STUDY SELECTION All English language randomized controlled trials evaluating the efficacy of mobilization techniques on range of motion (ROM) and pain in adult patients with primary AC of the shoulder were included in this systematic review. Twelve randomized controlled trials involving 810 patients were included. DATA EXTRACTION Two reviewers independently screened the articles, scored methodologic quality, and extracted data for analysis. The review was conducted and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. All studies were assessed in duplicate for risk of bias using the Physiotherapy Evidence Database Scale for randomized controlled trials. DATA SYNTHESIS The efficacy of 7 different types of mobilization techniques was evaluated. Angular mobilization (n=2), Cyriax approach (n=1), and Maitland technique (n=6) showed improvement in pain score and ROM. With respect to translational mobilizations (n=1), posterior glides are preferred to restore external rotation. Spine mobilizations combined with glenohumeral stretching and both angular and translational mobilization (n=1) had a superior effect on active ROM compared with sham ultrasound. High-intensity mobilization (n=1) showed less improvement in the Constant Murley Score than a neglect group. Finally, positive long-term effects of the Mulligan technique (n=1) were found on both pain and ROM. CONCLUSIONS Overall, mobilization techniques have beneficial effects in patients with primary AC of the shoulder. Because of preliminary evidence for many mobilization techniques, the Maitland technique and combined mobilizations seem recommended at the moment.

Arthroscopic bone block augmentation of the anterior glenoid through the rotator interval: a cadaveric feasibility study

HYPOTHESIS Arthroscopic augmentation of the anterior glenoid using a free bone graft through the rotator interval is possible without compromising the fixation and position of the graft MATERIAL AND METHODS In 7 cadavers arthroscopic augmentation of the anterior glenoid was performed. A preshaped, free graft was introduced and fixated with 1 central screw without desinsertion or split of the subscapularis tendon. Postoperatively, the orientation and position of the screw and position of the graft in the vertical and horizontal plane were analyzed on computer tomography (CT) scan. Macroscopic dissection was performed to assess damage to the conjoined and subscapularis tendon and surrounding neurovascular structures and to verify the position of the graft. RESULTS Postoperative CT scans showed no intra-articular perforation of the screw. The mean inclination angle in the axial plane was 21,2° (range, 9-48°). Postoperative dissection showed no damage to surrounding neurovascular structures. Fraying occurred at the lateral border of the conjoined tendon in 3 specimens, at the upper border of the subscapularis in 5 cases, but no tears were noted. In the vertical plane, the augmentation block was correctly (subequatorial) positioned in 5 cases; 2 blocks were at the level of the equator. In the horizontal plane, the augmentation block was flush with the articular surface in 5 cases and too medial in 2 cases (<5 mm). CONCLUSION This study showed that it is technically possible to perform a bone block procedure arthroscopically through the rotator interval without compromising the position and fixation of the graft and fixation screw.

Restoration of Articular Geometry Using Current Graft Options for Large Glenoid Bone Defects in Anterior Shoulder Instability

PURPOSE The purpose of this cadaveric study was to compare standard and modified coracoid transfer procedures, bicortical and tricortical iliac crest autografts, and tibial plafond and glenoid allografts with respect to glenoid surface curvature restoration. METHODS Computed tomography scans of 8 cadaveric shoulders were acquired in 9 conditions: (1) intact, (2) 25% width defect, (3) classic Latarjet, (4) modified congruent-arc Latarjet, (5) tricortical iliac crest inner table, (6) outer table, (7) bicortical iliac crest, (8) distal tibia, and (9) glenoid allograft. Outcome measures included articular surface area, width, depth, axial and coronal radius of curvature, and subchondral articular step-off, analyzed in bone and soft-tissue window. RESULTS Reconstruction of the articular surface area was optimal with the glenoid allograft (99.4%), classic Latarjet (97.4%), and iliac crest bicortical graft (93.2%). Depth was best restored by the congruent-arc Latarjet (101.0%), tibial (98.9%), and glenoid (95.3%) allografts. Axial curvature was closely matched by the glenoid allograft (97.5%), classic Latarjet (108.7%), and iliac bicortical graft (91.2%). Coronal curvature was most accurately restored by the glenoid allograft (102.6%), the tibial allograft (115.0%), and the classic Latarjet (55.9%). The articular step-off was smallest using the glenoid allograft. CONCLUSIONS Overall, glenoid allografts most accurately restored articular geometry. Alternative grafts provided restoration of some parameters but not others. Classic Latarjet performed well in axial and coronal curvature on average but exhibited large variability. Tibial allograft produced the poorest results in axial curvature, despite excellent coronal curvature reconstruction. The congruent-arc Latarjet did not restore the axial curvature accurately and overcorrected coronal curvature. Graft geometry must be weighed against availability, morbidity, and the role of additional stabilizers. CLINICAL RELEVANCE Accurate graft morphology may help prevent postoperative osteoarthritis. Grafts differ significantly regarding geometric parameters. The findings of this study will help surgeons select the most appropriate graft for glenoid reconstruction.

Mid-range shoulder instability modeled as a cam-follower mechanism

In this paper, we model a simplified glenohumeral joint as a cam-follower mechanism during experimental simulated dislocation. Thus, humeral head trajectory and translational forces are predicted using only contact surface geometry and compressive forces as function inputs. We demonstrate this new interpretation of glenohumeral stability and verify the accuracy of the method by physically testing a custom-molded, idealized shoulder model and comparing data to the output of the 2D mathematical model. Comparison of translational forces between experimental and mathematical approaches resulted in r(2) of 0.88 and 0.90 for the small and large humeral head sizes, respectively. Comparison of the lateral displacement resulted in r(2) of 0.99 and 0.98 for the small and larger humeral head sizes, respectively. Comparing translational forces between experiments and the mathematical model when varying the compressive force to 30 N, 60 N, and 90 N resulted in r(2) of 0.90, 0.82, and 0.89, respectively. The preliminary success of this study is motivation to introduce the effects of soft tissue such as cartilage and validation with a cadaver model. The use of simple mathematical models such as this aid in the set-up and understanding of experiments in stability research and avoid unnecessary depletion of cadaveric resources.