Tom R. Norris

Long-Term Results of Total Shoulder Arthroplasty Following Bone-Grafting of the Glenoid

Background: The marked loss of glenoid bone volume or alteration of glenoid version can affect glenoid component fixation in patients undergoing total shoulder arthroplasty. The purpose of this study was to evaluate the long-term results associated with the use of bone-grafting for restoration of glenoid volume and version at the time of total shoulder arthroplasty. Methods: Twenty‐one shoulders received an internally fixed, corticocancellous bone graft for the restoration of peripheral glenoid bone stock at the time of total shoulder arthroplasty between 1980 and 1989. Grafting was indicated when glenoid bone stock was insufficient to maintain adequate version or fixation of the prosthesis. Seventeen shoulders were available for follow‐up; the average duration of follow-up for the thirteen shoulders that did not have prosthetic failure within the first two years was seventy months. Total shoulder arthroplasty was performed because of osteoarthritis in five shoulders, chronic anterior fracture-dislocation in five, capsulorrhaphy arthropathy in three, inflammatory arthritis in two, recurrent dislocation in one, and failure of a previous arthroplasty in one. All patients had some form of anterior or posterior instability preoperatively. There were five anterior and twelve posterior glenoid defects. Bone from the resected humeral head was used for grafting in fifteen shoulders, and bicortical iliac-crest bone was used in two. Results: The average glenoid version after grafting was 4° of retroversion, with an average correction of 33°. The graft failed to maintain the original correction in three shoulders due to nonunion, dissolution, or shift. Five total shoulder replacements failed, necessitating glenoid revision at two to ninety‐one months postoperatively. The failures were associated with recurrent massive cuff tears (one shoulder), persistent instability (two shoulders), improper component placement (one shoulder), and loss of graft fixation (one shoulder). There were no humeral component failures. According to the criteria of Neer et al., the functional result was rated as excellent in three shoulders, satisfactory in six, and unsatisfactory in eight. Conclusions: Despite the finding that eight shoulders had an unsatisfactory functional result at the time of long-term follow-up, corticocancellous grafting of the glenoid successfully restored glenoid version and volume in fourteen of the seventeen shoulders in the present study. Patients with glenoid deficiency often have associated glenohumeral instability, which may affect the results of total shoulder arthroplasty. Bone-grafting of the glenoid is a technically demanding procedure that can restore bone stock in patients with structural defects.

Late prosthetic shoulder arthroplasty for displaced proximal humerus fractures

Twenty-three shoulders in 23 patients with failed treatment of three- and four-part proximal humerus fractures subsequently treated with prosthetic arthroplasty were reviewed. The initial treatment was closed in 10 cases and open in 13. The complications of treatment included malunions in 17, nonunions in four, traumatic arthritis in 14, avascular necrosis in nine, humeral shortening in six, and deltoid paresis in four. In 20 cases prosthetic arthroplasty was performed an average of 15.8 months after injury. Three other cases had arthroplasty 19, 20, and 22 years after the original fracture. Seventeen were treated with a total shoulder arthroplasty, and six had a humeral head replacement. Thirteen had a tuberosity osteotomy, and eight had lengthening of the subscapularis tendon. Prosthetic arthroplasty reduced the shoulder pain in 22 (95%). Average active forward elevation increased from 68 degrees to 92 degrees, and active external rotation increased from 6 degrees to 27 degrees. After arthroplasty 53% of the patients were able to do activities at or above shoulder level compared with 15% before arthroplasty. Late surgery for failed early treatment is technically difficult, and the results are inferior to those reported for acute humeral head replacement. These findings should be considered when treatment is selected for acute three- and four-part proximal humerus fractures. Nonetheless late arthroplasty is a satisfactory reconstructive option when primary treatment of proximal humerus fractures fails.

Operative Treatment of Malunion of a Fracture of the Proximal Aspect of the Humerus

We retrospectively reviewed the medical records, operative reports, and preoperative and postoperative radiographs of thirty-nine patients who had been managed operatively for malunion of a fracture of the proximal aspect of the humerus. The malunions were categorized according to the presence of osseous abnormalities, including malposition of the greater or lesser tuberosity (type I; twenty-eight patients), incongruity of the articular surface (type II; twenty-six patients), and malalignment of the articular segment (type III; sixteen patients). Soft-tissue abnormalities, such as soft-tissue contracture, a tear of the rotator cuff, and impingement, were also recorded. At an average of forty-four months (range, twelve to fifty-three months) postoperatively, the patients were assessed for pain relief, the range of motion of the shoulder, and the ability to perform activities of daily living. The result was satisfactory for twenty-seven patients (69 per cent) and unsatisfactory for the remaining twelve (31 per cent) at the latest follow-up evaluation. Of the twenty-seven patients who had a satisfactory result, twenty-six (96 per cent) had had complete operative correction of all osseous and soft-tissue abnormalities. Of the twelve patients who had an unsatisfactory result, four had had complete operative correction of these abnormalities (p < 0.0001). Twenty-six patients (67 per cent) had incongruity of the glenohumeral joint at the time of presentation. Twenty-three of these patients had the incongruity corrected with prosthetic arthroplasty (twenty-two) or arthrodesis of the glenohumeral joint (one); the result was satisfactory for seventeen (74 per cent). In contrast, the result was unsatisfactory for all three patients in whom the incongruity had not been corrected at the time of the operation (p = 0.01). Eleven patients had malposition of the greater or lesser tuberosity but a congruent joint surface preoperatively. Ten patients in this group were managed with either osteotomy of the tuberosity or acromioplasty, and nine of them had a satisfactory result at the latest follow-up evaluation. The result was unsatisfactory for one patient who was managed with only correction of a soft-tissue contracture (that is, no treatment of the malposition) (p = 0.05). Both osseous and soft-tissue abnormalities were identified as the cause of pain and stiffness in patients who had malunion of a fracture of the proximal aspect of the humerus. We concluded that operative management of these patients is successful only if all osseous and soft-tissue abnormalities are corrected at the time of the operation.

Periprosthetic humeral fractures: Mechanisms of fracture and treatment options

In 20 patients, 21 periprosthetic humeral fractures were reviewed retrospectively. The mean follow-up time was 27.1 months. Mild osteopenia was present in 45% of the patients, whereas 30% had severe osteopenia. Five mechanisms of fracture were identified, including 3 intraoperative causes that are avoidable. Treatment with stable intramedullary fixation utilizing the humeral stem and cerclage wiring provided superior results in terms of time to union, adverse effect on rehabilitation, and occurrence and severity of surgical complications. Diaphyseal fractures that were treated with standard stem arthroplasty with or without supplemental fixation had a longer time to fracture union, a higher complication rate, and prolonged rehabilitation. Fractures of the proximal humeral metaphysis can be treated with standard stem arthroplasty and cerclage wiring if the stem extends distal to the fracture site by at least 3 cortical diameters. Anatomic reduction of fractures treated by surgical means results in shorter healing times. Cast or brace immobilization can be used for management of postoperative fractures that occur distal to a well-fixed and stable prosthetic stem. Cast or brace immobilization results in fracture union but rehabilitation may be greatly impaired, and there is an increased risk of complications associated with immobilization of the extremity. Long-stem intramedullary fixation with cerclage wiring is the preferred surgical option for treatment of unstable humeral shaft fractures.

Optimizing glenosphere position and fixation in reverse shoulder arthroplasty, Part One: The twelve-mm rule

The Aequalis Reversed Shoulder Prosthesis (Tornier, Inc., Edina, MN) is a successful treatment option for older, low-demand patients with rotator cuff arthropathy. Scapular notching is the most common radiographic complication and is associated with poorer intermediate-term clinical outcomes. Aligning the lower border of the glenosphere baseplate with the inferior glenoid rim has been recommended to reduce this complication, but guidelines for achieving this positioning are currently lacking. The purpose of this study is to develop a rule of thumb that will facilitate proper glenosphere component positioning intraoperatively. Utilizing a computed tomography-templating protocol, we found that the ideal location of the drill hole for the baseplate post was 11.5 +/- 1.0 mm above the inferior glenoid rim. On the basis of measurements from 10 implanted cadaveric specimens, we concluded that drilling the baseplate posthole 12 mm above the inferior glenoid rim-the 12-mm rule-will result in excellent glenosphere position in most cases.

Optimizing glenosphere position and fixation in reverse shoulder arthroplasty, Part Two: The three-column concept

Scapular geometry is complex, and a screw-placement technique for optimizing glenoid component fixation with an Aequalis Reversed Shoulder Prosthesis (Tornier, Inc., Edina, MN) has not yet been described. Ten cadaveric human scapulae were implanted with 2 types of reverse arthroplasty baseplates, 1 with fixed-angle locking screw holes and 1 with multidirectional locking screw holes. Optimal screw placement was defined as that which maximized screw length, accomplished far cortical fixation, and attained screw purchase in good bone stock. An anterior cruciate ligament drill guide was used to find the ideal trajectory for each screw. Trajectory angles of the screws relative to the face of the baseplate are presented for what we believe is best possible fixation. Awareness of the 3 major columns of scapular bone (the base of coracoid, the spine, and the pillar) and utilization of a baseplate with variable-angle locking screws will allow optimal initial fixation of the glenosphere.

Clinical results of revision shoulder arthroplasty using the reverse prosthesis

BACKGROUND Success of revision shoulder arthroplasty using an unconstrained prosthesis depends on an intact rotator cuff and satisfactory bone quantity. However, the reverse shoulder arthroplasty can stabilize a glenohumeral joint even in patients with rotator cuff deficiency and bone deficits, resulting in improved outcomes. MATERIALS AND METHODS Thirty shoulders in 28 patients with a failed arthroplasty were investigated consecutively between 2005 and 2008. All shoulders had significant rotator cuff deficiency without glenoid bone loss. Revision arthroplasty using the reverse prosthesis was performed with a minimum of 2 years of follow-up. Concomitant glenoid reconstructions with tricortical iliac crest bone grafting were necessary in 12 shoulders. RESULTS The average adjusted Constant score improved from 24% to 65% and the American Shoulder and Elbow Surgeons (ASES) score improved from 55 to 72 (P < .0001). Average active forward flexion increased from 42° to 106° (P < .0001). The average ASES pain score improved from 6.6 to 1.6 (P < .0001). The overall complication rate was 50%, and 7 patients (23%) required reoperation. Overall, 24 of 30 shoulders (80%) were very satisfied or satisfied. CONCLUSION Reverse shoulder arthroplasty can be an efficacious salvage procedure in the management of failed arthroplasty due to rotator cuff-related instability or bone defects, or both. Structural bone grafting on the glenoid side is successful at managing large defects, producing similar or better clinical outcomes compared with patients without bone loss. Although the operation is associated with a considerable complication rate, 80% of patients were satisfied with the results of the procedure, and 29 of 30 shoulders had a stable prosthesis.

Radiographic and clinical outcomes of total shoulder arthroplasty with an all-polyethylene pegged bone ingrowth glenoid component: prospective short- to medium-term follow-up

BACKGROUND Glenoid components often cause total shoulder arthroplasty failure. This study examines short-term to midterm radiographic and clinical results of a hybrid glenoid component with 3 cemented peripheral pegs and a central peg, which allows biologic fixation with use of native humeral head autograft. METHODS In 4 years, 80 glenoid components were implanted during primary total shoulder arthroplasty with at least 2-year follow-up data. Within 12 months, 4 shoulders were revised and excluded from final analyses. Seven patients did not complete their questionnaires. Outcomes data included the American Shoulder and Elbow Surgeons (ASES) questionnaire, Constant score, and satisfaction score. A shoulder and elbow fellowship-trained surgeon, not involved in the care of these patients, analyzed radiographs for radiolucent lines, glenoid seating, and radiodensity in between the flanges of the central peg. RESULTS Only 1 of 80 shoulders was revised for aseptic glenoid loosening. At final follow-up, 81.6% had a radiolucency grade of 0 or 1. Nearly 90% had a glenoid seating grade of A or B. Grade 2 or 3 bone around the central peg was seen in 88.2%. No statistical association existed between Walch glenoid types and radiolucency grades, bone grades around the central peg, perfect radiolucency grade, seating grade, and grade 3 bone around the central peg. There was significant improvement in mean ASES score, adjusted ASES pain score, Constant score, and satisfaction score as well as in forward flexion, abduction, and external rotation. CONCLUSIONS The hybrid glenoid can produce stable radiographic and clinical outcomes at short- to medium-term follow-up.

Humeral head replacement for four-part fractures and fracture-dislocations

Abstract Prosthetic replacement for acute four-part displaced fractures of the proximal humerus is recommended over other forms of treatment. Fixation of the tuberosities through the rotator cuff attachments avoids potential dehiscence from repairs using the soft osteoporotic tuberosities. Cable supplementation secures tuberosities to the shaft, thereby allowing earlier, safe motion to prevent the stiffness that can accompany these difficult fractures.

Unscrewing instability of modular reverse shoulder prosthesis increases propensity for in vivo fracture: a report of two cases.

A modular cemented Tornier Aequalis RSA (Tornier,Bloomington, MN, USA) was retrieved from the leftshoulder of a 79-year-old male patient after 9 years2 months in vivo (Fig. 1, A). The patient’s proximal hu-merus initially fractured during a ground-level fall. Surgerywas then performed with open reduction and internal fix-ation with a proximal humeral locking plate. This fixationfailed, and a hemiarthroplasty surgery was then performed.Because the tuberosity fixation failed, revision hemi-arthroplasty surgery was performed. After the third surgi-cal procedure, the tuberosities resorbed with subsequentanterior-superior escape of the prosthesis. There was also a5-cm area of proximal humeral bone loss. Another revisionsurgery was then performed with conversion to a reverseprosthesis. Preoperative radiographs showed partial disas-sembly of the screw joint between the metaphysis anddiaphysis on the humeral stem (Fig. 1, B). The implant hadnot yet fractured or dissociated completely (Fig. 1, C).Extensive metallosis was observed in the retrieved peri-prosthetic tissue (Fig. 1, D).Retrieval analysis including optical and metric evalua-tion showed a gap at the junction of the metaphysis anddiaphysis. The 2 components were disassembled ex vivo,