Aims

As has been shown in larger animal models, knee immobilization can lead to arthrofibrotic phenotypes. Our study included 168 C57BL/6J female mice, with 24 serving as controls, and 144 undergoing a knee procedure to induce a contracture without osteoarthritis (OA).

Aims

Outcomes of current operative treatments for arthrofibrosis after total knee arthroplasty (TKA) are not consistently positive or predictable. Pharmacological in vivo studies have focused mostly on prevention of arthrofibrosis. This study used a rabbit model to evaluate intra-articular (IA) effects of celecoxib in treating contracted knees alone, or in combination with capsular release.

Aims

Arthrofibrosis is a relatively common complication after joint injuries and surgery, particularly in the knee. The present study used a previously described and validated rabbit model to assess the biomechanical, histopathological, and molecular effects of the mast cell stabilizer ketotifen on surgically induced knee joint contractures in female rabbits.

Objectives

Sustained intra-articular delivery of pharmacological agents is an attractive modality but requires use of a safe carrier that would not induce cartilage damage or fibrosis. Collagen scaffolds are widely available and could be used intra-articularly, but no investigation has looked at the safety of collagen scaffolds within synovial joints. The aim of this study was to determine the safety of collagen scaffold implantation in a validated in vivo animal model of knee arthrofibrosis.

Aims

Animal models have been developed that allow simulation of post-traumatic joint contracture. One such model involves contracture-forming surgery followed by surgical capsular release. This model allows testing of antifibrotic agents, such as rosiglitazone.

Summary

Based upon genetic analysis, decorin is an exciting pharmacologic agent of potential anti-fibrogenic effect on arthrofibrosis in our animal model.

Objectives

The goal of this study was to determine whether intra-articular administration of the potentially anti-fibrotic agent decorin influences the expression of genes involved in the fibrotic cascade, and ultimately leads to less contracture, in an animal model.

Purpose: Resection elbow arthroplasty is a salvage procedure typically considered as a last resort when other reconstructive options have failed. It was the intent of this study to evaluate the long-term outcome of patients following resection elbow arthroplasty.

Method: Fifty-four elbow resections performed between 1975 and 2005 were retrospectively reviewed. Pre and post-operative elbow function was evaluated with the Mayo Elbow Performance Score (MEPS) and additional follow-up data was compiled using the Disability of Shoulder and Hand (DASH) score. All patients in this study had a resection following a failed total elbow arthroplasty (TEA). Nineteen patients had died at time of follow-up, and 5 patients were lost to follow-up, leaving 30 of the surviving 34 patients (88%) available for long-term evaluation.

Results: The main indication for resection in this study was infection (50 of 54 elbows). The average MEPS prior to resection was 36. The long-term results in 30 patients at an average of 11 yrs (range 2.7–28 yrs) demonstrated an average MEPS score of 60, and a DASH score of 71. Complications were common including persistent infection requiring re-operation (44%), intra-operative fracture (32%), transient (11%) or permanent (5.5%) nerve damage, and one case of vascular injury requiring amputation. Achieving a stable resected elbow correlated strongly with a good long-term MEPS score (r=0.75).

Conclusion: This study emphasizes the difficulty in treating patients with a failed total elbow arthroplasty. Resection arthroplasty is a salvage procedure indicated primarily for persistently infected TEA and results in satisfactory outcomes in this population.

Purpose: The long-term experience of linked semicon-strained total elbow arthroplasty was investigated as a salvage procedure for patients with distal humerus non-union not amenable to internal fixation.

Method: Ninety-two consecutive total elbow arthroplasties performed for the treatment of a distal humeral nonunion were reviewed at an average follow-up of 6.5 years (range, 0.5 to 20.3 years). There were twenty-two men and sixty-nine women with an average age of sixtyfive years (range, twenty-two to eighty-four years) at the time of elbow replacement. Seventy-six elbows (83 per cent) had undergone prior surgery, with an average of two previous operations (range, one to ten). Five elbows had had at least one prior operation due to infection.

Results: Seventy-nine per cent of the patients had no pain or mild pain at latest follow-up compared with moderate or severe pain in 86 percent prior to surgery. Mean extension was improved from thirty-seven to twenty-two degrees and mean flexion from 106 to 135 degrees. Joint stability was restored in all patients, including nine with a grossly flail elbow. Complications included aseptic loosening in sixteen (four with periprosthetic fractures), component fracture in five, deep infection in five (three with previous infection), and bushing wear in one patient. At most recent follow-up, 85 per cent of the patients were satisfied with their outcome. Survivorship for not requiring removal or revision for any cause was 95.7 per cent at two years, 82.1 per cent at five years, 65.3 per cent at ten and fifteen years. Factors that increased the risk of implant failure were patient age less than sixty-five, two or more prior surgeries, and history of previous infection.

Conclusion: Linked semiconstrained total elbow arthroplasty provides a reliable salvage procedure to provide pain relief and restoration of motion and function in patients with distal humerus nonunion not amenable to internal fixation. Risk factors for failure include younger patients, multiple previous surgeries, and history of infection.

Purpose: We conducted a retrospective review to evaluate outcomes, complications and implant survival after shoulder reconstruction for bone neoplasm using anatomic shoulder prostheses.

Method: Thirty-four anatomic shoulder prostheses were reviewed at an average follow-up of 51 (range, 6 to 143) months. The mean age at the time of surgery was 47 (range, 15 to 74) years. Twenty-five patients (74%) had reconstruction with an allograft-prosthetic composite (APC). The average amount of humerus resected in patients with an APC was 13 cm (range, 5 to 36 cm).

Results: At most recent follow-up, 82% of patients had no pain (11), slight pain (12) or moderate pain with strenuous activities (5). Twenty-eight patients (82%) were subjectively satisfied despite only 29% being satisfactory according to Neer rating. Sixteen complications occurred in 13 patients, including instability (5), host/graft non-union (3), aseptic loosening (3), arthrofibrosis (1), tumor recurrence (2) and superficial infection (1). Host/graft nonunion occurred in 3/9 patients with an APC using press-fit or plate fixation for distal humeral fixation and 0/16 shoulders with cemented distal humeral fixation (p=0.02). Three implants required revision for aseptic loosening (1), host/graft nonunion (1) and instability (1). Kaplan-Meier survivorship at 10 years was 88% for implant revision and 80% for mechanical failure.

Conclusion: Reconstruction of the proximal humerus using an anatomic prosthesis after resection of bone neoplasms is associated with a low rate of mechanical failure but a moderate rate of shoulder instability. Cement fixation into the native distal humerus should be considered when reconstruction using an APC is required.

Purpose: Loosening of the humeral component is rarely a cause for revision shoulder surgery. Most long-term series are not large enough to stratify the many risk factors that might influence the survivorship of humeral component designs. The purpose of this study was to determine long-term survivorship of the Neer and Cofield humeral components and to define the risk factors associated with humeral component removal or revision.

Method: 1584 primary Neer and Cofield shoulder arthroplasties (1423 patients) were performed at our institution from 1984 to 2004. There were 619 men (694 shoulders) and 804 women (890 shoulders), with a mean age at arthroplasty of 65.6 years (range, 16–94 years). Kaplan-Meier survivorship analysis was used to determine the effect of etiology of the disease, gender, age, surgery type (hemi versus total), fixation type (cemented versus noncemented), and the humeral component type (Neer II, Cofield I or II) on the estimated survival free of humeral component revision or removal.

Results: There were 108 revisions and 17 removals of the humeral component. The overall rate of removal or revision of the humeral component was 7.9% with an average followup of 8.1 years. The rates of survivorship free of revision or removal of the humeral component for any reason was 94.8% at 5 years, 92% at 10 years, 86.7% at 15 years and 82.8% at 20 years. Seventy-one of 632 shoulders (11.2%) in patients younger than 65 years required humeral component revision or removal, whereas only 54 of 952 shoulders (5.7%) in patients 65 years and older required humeral component revision or removal (Odds ratio=2.1; 95% confidence interval, 1.5–3, p=0.001). Patients with posttraumatic arthritis had a higher risk of needing revision or removal of the humeral component (Odds ratio=2.1, 95% confidence interval 1.3–3.3) compared to osteoarthritis. Eighty-four of 526 shoulders (16.0%) with metal-back glenoid components required humeral component revision or removal, whereas only 41 of 1058 shoulders (3.9%) with non metal-backed glenoid components required humeral component revision or removal (Odds ratio=4.7; 95% confidence interval, 3.2–7, p=0.001).

Conclusion: Younger age, replacement due to post-traumatic arthritis and presence of a metal-backed glenoid increased the likelihood of humeral component failure. Similar short-term survival can be achieved with Cofield II and Neer II humeral components.

The purpose of this study is to report our experience with revision of total elbow arthroplasty by exchange cementation. Between 1982 and 2004 at our institution, forty six elbows were treated with exchange cementation of a total elbow arthroplasty into the existing cement mantle or debrided bone interface, without the use of an osteotomy, bone graft or prosthetic augmentation. Indications for the procedure were aseptic loosening (17), second stage after septic loosening (14), instability (7), prosthetic fracture (4), periprosthetic fracture (2), failed hemiarthroplasty (1) and ulnar component wear (1). Both components were exchanged in 18 elbows, the humerus alone in 25 and the ulna in 3. Mean follow up was 90.5 months (10 to 266 months);18 patients had died with the prosthesis in situ. Complications were noted in 22 elbows; periprosthetic fracture of ulna (6) and humerus (2), humeral component fracture (1), aseptic loosening (4), non-union (1), heterotrophic ossification (2), soft tissue contracture (2) and soft tissue failure (2), delayed wound healing (1) and bushing failure (1). Reoperation was required in 10 elbows for revision of both components (2), ulna (3), humerus (1), bushing revision (2), soft tissue debridement (1) and soft tissue repair (1). There were no septic recurrences in previously infected elbows; however the reoperation rate in this group was 29% versus 19% after re-cementation for other causes. Revision of total elbow arthroplasty by exchange cementation is a reasonable treatment for those elbows with adequate bone stock for secure prosthetic fixation; however careful consideration should be given to augmentation of the ulna due to the high rate of periprosthetic fracture in this series. Re-cementation following débridement for infection is effective despite having a higher rate of revision operation compared to re-cementation in the aseptic elbow.

Aims: The purpose of this study was to determine the outcome of fracture fixation with a principle-based technique that maximizes screw purchase in the articular fragments and compression at the supracondylar level. Methods: Thirty-one consecutive complex distal humerus fractures were fixed with two (medial and lateral) parallel plates applied according to the following principles: (1) all distal screws pass through plates, and (2) are anchored into a fragment on the opposite side fixed by a plate, (3) distal screws are as long and numerous as possible, (4) supracondylar interfragmentary compression is applied, and (5) full motion with no protection is routinely commenced within 36 hours after surgery. Twenty-five fractures (81 per cent) were AO type C3 and fourteen (42 per cent) were open. Two patients died in the first month after surgery. The remaining patients were followed for a mean of two years. Results: Neither hardware failure nor fracture displacement occurred in any patient. Union was achieved primarily in 28 cases (97 per cent). Three patients underwent further surgery for heterotopic ossification with associated stiffness. Another patient required interposition arthroplasty for secondary degenerative changes. At most recent follow-up, twenty-four elbows had no or mild pain and the median flexion- extension arc was from 27 to 124 degrees. The mean Mayo Elbow Performance Score was 83.1 points (range, fifty-five to 100 points). The results were graded as excellent in nine, good in fifteen, fair in two and poor in three cases. Conclusions: Fixation of complex fractures of the distal humerus with the above-described principle-based technique allows intensive rehabilitation of elbow motion immediately after surgery and is associated with a high union rate.

Aims: Tension band wiring is a widely accepted method for internal þxation of olecranon fractures. Plate þxation is suggested for the more complex olecranon fractures, but little is known about the speciþc risk factors for failure of tension band wiring. The aim of this study was to analyze the inßuence of fracture comminution, associated elbow instability and fracture extension into the coronoid process on the outcome of tension band wiring for olecranon fractures. Methods: From 1996 to 1998, forty-four olecranon fractures were treated consecutively at out institution using tension band wiring. All patients returned for a clinical and radiographic exam performed by two observers independent of the treating surgeon. Pain and satisfaction were determined using visual-analogue scales (VAS) and clinical results were graded using the Mayo Elbow Performance Score (MEPS) and the DASH questionnaire. Patients were followed for 3 to 6 years. Results: At most recent follow-up, the mean VAS score for pain was 2.0, mean extension was 3.6û and mean ßexion was 137.2û. According to the MEPS the results were graded as good or excellent in 78% of the patients. Five patients were disabled for activities of daily living according to the DASH questionnaire. All but one fracture healed. Fracture comminution did not affect the outcome. Worse results were associated with elbow instability and fracture extension into the coronoid. Conclusions: Tension band wiring provided satisfactory results for the treatment of olecranon fractures in the presence of fracture comminution, but worse results were obtained in the presence of elbow instability and fracture extension into the coronoid.

Aims: Posterolateral rotatory instability of the elbow is believed to express dysfunction of the lateral collateral ligament complex. The purpose of this study was to determine the long-term results of lateral ligamentous reconstruction in patients with posterolateral rotatory instability of the elbow. Methods: From 1986 to 1999, forty-þve consecutive elbows with posterolateral rotatory instability were treated by direct repair of the lateral ligament complex (twelve cases) or augmented reconstruction with a tendon autograft (thirty-three cases). One patient was lost to follow-up one year postoperatively. The remaining forty-four patients were followed for an average of six (range, two to þfteen) years. Results: Surgery initially restored elbow stability in all but þve cases, two of which became stable after a second procedure. At most recent follow-up, three of the forty-þve patients had persistent instability. The most recent mean Mayo Elbow Performance Score was eighty-þve points (range, sixty to 100 points). According to the rating system of Nestor et al., the result was excellent in nineteen, good in thirteen, fair in seven and poor in þve cases. Thirty-eight patients (86 per cent) were subjectively satisþed with the outcome of the operation. Better results were obtained in patients with a postraumatic etiology (p=0.03), subjective complains of instability at presentation (p=0.006), and augmented reconstruction using a tendon graft (p=0.04). Conclusions: Lateral ligamentous reconstruction is an effective long-term procedure for posterolateral rotatory instability. Reconstruction using a tendon graft seems to provide better results than ligament repair. The results of ligamentous reconstruction do not seem to deteriorate with time.