A prospective radiostereometric analysis of the stability of a metal-backed glenoid component/autograft composite in reverse shoulder arthroplasty.

Aims: Reverse total shoulder arthroplasty (rTSA) can be used in complex cases when the glenoid requires reconstruction. In this study, a baseplate with composite bone autograft and a central trabecular titanium peg was implanted, and its migration was assessed for two years postoperatively using radiostereometric analysis (RSA). Methods: A total of 14 patients who underwent a rTSA with an autograft consented to participate. Of these, 11 had a primary rTSA using humeral head autograft and three had a revision rTSA with autograft harvested from the iliac crest. The mean age of the patients was 66 years (39 to 81). Tantalum beads were implanted in the scapula around the glenoid. RSA imaging (stereographic radiographs) was undertaken immediately postoperatively and at three, six, 12, and 24 months. Analysis was completed using model-based RSA software. Outcomes were collected preoperatively and at two years postoperatively, including the Oxford Shoulder Score, the American Shoulder and Elbow Score, and a visual analogue score for pain. A Constant score was also obtained for the assessment of strength and range of motion. Results: RSA analysis showed a small increase in all translation and rotational values up to six months postoperatively, consistent with settling of the implant. The mean values plateaued by 12 months, with no evidence of further migration. In four patients, there was significant variation outside the mean, which corresponded to postoperative complications. There was a significant improvement in the clinical and patient-reported outcomes from the preoperative values to those at two years postoperatively (p < 0.001). Conclusion: These findings show, using RSA, that a glenoid baseplate composite of a trabecular titanium peg with autograft stabilizes within the glenoid about 12 months after surgery, and reinforce findings from a previous study of this implant/graft with CT scans at two years postoperatively, indicating that this type of structural composite results in sound early fixation.

Clinical and radiologic outcomes of Lima ProMade custom 3D-printed glenoid components in primary and revision reverse total shoulder arthroplasty with severe glenoid bone loss: a minimum 2-year follow-up.

BACKGROUND: The purpose of this study is to report the clinical and radiologic outcomes of patients undergoing primary or revision reverse total shoulder arthroplasty using custom 3D-printed components to manage severe glenoid bone loss with a minimum of 2-year follow-up. METHODS: Following ethical approval, patients were identified and invited to participate. Inclusion criteria were (1) severe glenoid bone loss necessitating the need for custom implants and (2) patients with definitive glenoid and humeral components implanted more than 2 years prior. Included patients underwent clinical assessment using the Oxford Shoulder Score (OSS), Constant-Murley score, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), and the quick Disabilities of the Arm, Shoulder, and Hand questionnaire (QuickDASH). Radiographic assessment included anteroposterior and axial projections. Patients were invited to attend a computed tomography (CT) scan to confirm osseointegration. Statistical analysis used descriptive statistics (mean and standard deviation [SD]) and paired t test for parametric data. RESULTS: Eleven patients declined to participate. Five patients were deceased prior to study commencement, leaving 42 remaining patients in this analysis. Three patients had revision surgery before the 2-year follow-up; of these, 2 retained their custom glenoid components. Mean follow-up was 31.6 months from surgery (range 24-52 months). All 4 scores improved: OSS from a mean 15 (SD 8.4) to 36 (SD 12) (P < .001), Constant-Murley score from a mean 15 (SD 11.2) to 52 (SD 20.1) (P < .001), QuickDASH from a mean 70 (SD 21) to 31 (SD 24.8) (P = .004), and the ASES score from a mean 22 (SD 17.8) to 71 (SD 23.3) (P = .007). Radiologic evaluation demonstrated good osseointegration in all but 1 included patient. CONCLUSION: The utility of custom 3D-printed components for managing severe glenoid bone loss in primary and revision reverse total shoulder arthroplasty yields significant clinical improvements in this complex cohort. Large complex glenoid bone defects can be managed successfully with custom 3D-printed glenoid components.

Survivorship of Allologous Structural Bone Graft at a Minimum of 2 Years When Used to Address Significant Glenoid Bone Loss in Revision Shoulder Arthroplasty: A Computed Tomographic and Clinical Review.

Background: This study assesses outcomes in revision shoulder replacements where the glenoid bone loss was managed using a structural allograft (donated femoral head) in combination with a trabecular titanium (TT) implant. Methods: We contacted patients who had undergone revision shoulder arthroplasty using the Lima Axioma TT metal-backed glenoid with an allologous bone graft as a composite who were over 2 years since surgery. Patients underwent computerd tomography evaluation, clinical review, and scoring preoperatively, at 6 months and the latest follow-up. Results: Fifteen patients were included with a mean age of 59 (33-76). The average follow-up period was 40.5 months (24-51). 80% showed satisfactory bone graft incorporation and peg integration at the latest follow-up. Three had signs of significant bone graft resorption, although in 2 patients the pegs were still soundly fixed in the host bone. Clinically all patients showed a statistically significant improvement in pain relief, movement, and function. No unusual complications were reported. Conclusion: Results show femoral head structural allograft in combination with TT metal-backed glenoid baseplate is a viable option for revision total shoulder replacement in the context of massive glenoid bone loss. We do, however, acknowledge that this resorption rate is higher than in other reported series where autograft is used.

Capitate shortening osteotomy and vascularized bone grafting for Kienböck's disease in ulnar positive or neutral wrists.

We report the short- to medium-term outcomes for patients with Kienböck's disease and ulnar positive or neutral wrists treated by capitate shortening osteotomy combined with a 4 + 5 extensor compartmental artery vascularized bone graft placed in the lunate. This is a retrospective study of seven consecutive patients with Lichtman Stage 2 to 3B. Radiological and clinical outcomes were evaluated. Six patients maintained their Lichtman stage, one progressed. Mean time to union of the capitate was 10 weeks. Five of six lunates were completely revascularized on MRI scans, with one partial revascularization. Mean follow-up for functional scores was 40 months (range 15 to 62). Mean pain score improved significantly from 7.4/10 preoperatively to 1.9/10 postoperatively, and patient satisfaction was 9.2/10. Mean postoperative Quick Disabilities of Arm, Shoulder and Hand, Patient Evaluation Measure and Patient-Rated Wrist Evaluation scores were improved. All patients returned to their previous work. We conclude that this procedure has good short- to medium-term outcomes.Level of evidence: IV.

Radiographic and Computed Tomography Correlation of Kienböck's Disease: Is There a Need to Revisit Staging with Improved Imaging?

Carpal height ratio and ulnar variance on plain X-ray were measured and compared to the width/height ratio of the lunate as measured on a computed tomography (CT) scan in 50 patients with Kienböck's disease. Width/height ratio of the lunate was also measured in a series of 50 controls. No correlation between ulnar variance and fractures was found. Conversely, the correlation between carpal height ratio on X-ray and width/height ratio on a CT scan was statistically significant. Similarly, the correlation between ulnar variance and width/height ratio was statistically significant. We have concluded that width/height ratio while correlating with carpal height is a better measure of lunate collapse. It also appeared that lunate collapse precedes carpal collapse, specifically most if not all lunates have collapsed prior to reduction in carpal height ratio. Finally, while we are unable to conclude the level at which the width/height ratio of lunate becomes unreconstructable, it does appear that in all Litchman stage 3b and most if not all of 3a the shape of the lunate has altered significantly.

Wear behaviour of polyethylene glenoid inserts against PyroCarbon humeral heads in shoulder arthroplasties.

The generation of polyethylene wear debris, and the subsequent tissue reaction to such debris is considered to be a limitation in the long-term survival of shoulder arthroplasties. The purpose of this study was to investigate, for the first time, the wear of a novel PyroCarbon-on-Polyethylene (PyCoP) shoulder arthroplasty system. A 5 million cycle wear test was performed on PyroCarbon humeral heads, which were articulated against commercially available polyethylene glenoid insert components to form an anatomic total shoulder arthroplasty (aTSA). A "Repeat-motion-load" physiological combined cycle was applied using the unique Newcastle Shoulder Wear Simulator. Wear was assessed gravimetrically, and the change of the surface roughness was measured with a non-contacting profilometer. The mean wear rate of the ultra-high molecular weight polyethylene (UHMWPE) components was 19.3 ± 9.5 mm3/million cycles after 5 million cycles of testing. The roughness value, Sa, of the UHMWPE glenoid inserts, reduced, changing from 296 ± 28 nm Sa to 32 ± 8 nm Sa. In contrast, the mean roughness of the PyroCarbon humeral heads remained in the same range (21 ± 2 nm Sa to 20 ± 10 nm Sa). There was no reduction in weight (no measurable wear) of the PyroCarbon humeral heads over the duration of testing. This study is the first to describe the wear performance of UHMWPE glenoid inserts against PyroCarbon humeral heads. No significant difference in the wear of UHMWPE was found in comparison with published studies.

Early results of Latitude primary total elbow replacement with a minimum follow-up of 2 years.

BACKGROUND: The aim of this study was to present outcomes of primary Latitude total elbow replacement (TER) with a minimum follow-up of 2 years. METHODS: A retrospective cohort study was undertaken with prospective outcome data collection for the latest outcome. Included were 63 consecutive primary Latitude TERs in 58 patients performed during a period of 5 years at a specialist orthopedic hospital. RESULTS: The mean age of the patients was 62 years (33-85 years). Five primary TERs (4 patients) were lost to follow-up. The primary diagnosis was rheumatoid arthritis in 49, osteoarthritis in 8, and trauma in 6 elbows. The mean flexion-extension arc was 75° preoperatively and 97° postoperatively. Mean postoperative Elbex pain score was 19/100, and function score was 37/100. Mean postoperative scores were 42/100 for the Quick Disabilities of the Arm, Shoulder, and Hand and 38/50 for the elbow-specific American Shoulder and Elbow Surgeons assessment. Four patients died of unrelated causes, and 8 of 63 underwent further surgical intervention, including explantation and conversion from unlinked to linked implant. On radiographic review of 41 surviving TERs, aseptic radiologic loosening was observed of the humeral component in 4 elbows and of the ulnar component in 9. Seven elbows had no radial component, and of the remaining 34 elbows, 16 (47%) had signs of loosening of the radial implant. Complications included 1 heterotopic ossification, 1 olecranon fracture, and 3 further procedures for ulnar nerve entrapment. CONCLUSION: The results indicate that the early outcome of Latitude TER is comparable to that of other prostheses. There is concern about early radiologic loosening of the radial component.

Use of flexible elbow reamers for cement removal in the humerus during revision shoulder arthroplasty.

Humeral cement removal in revision shoulder arthroplasty can be challenging. Secondary damage to the bone and neighbouring structures can be extensive and compromise later reconstruction. We present a technique that employs flexible reamers from elbow arthroplasty instrumentation, which aids cement removal at the same time as minimizing the risk of iatrogenic injury.

Ten questions on prosthetic shoulder infection.

Prosthetic shoulder infection can cause significant morbidity secondary to pain and stiffness. Symptoms may be present for years before diagnosis because clinical signs are often absent and inflammatory markers may be normal. An emerging common culprit, Propionibacterium acnes, is hard to culture and so prolonged incubation is necessary. A negative culture result does not always exclude infection and new synovial fluid biochemical markers such as α defensin are less sensitive than for lower limb arthroplasty. A structured approach is necessary when assessing patients for prosthetic shoulder joint infection. This includes history, examination, serum inflammatory markers, plain radiology and aspiration and/or biopsy. A classification for the likelihood of prosthetic shoulder infection has been described based on culture, pre-operative and intra-operative findings. Treatment options include antibiotic suppression, debridement with component retention, one-stage revision, two-stage revision and excision arthroplasty. Revision arthroplasty is associated with the best outcomes.

Evaluating the Surface Topography of Pyrolytic Carbon Finger Prostheses through Measurement of Various Roughness Parameters.

The articulating surfaces of four different sizes of unused pyrolytic carbon proximal interphalangeal prostheses (PIP) were evaluated though measuring several topographical parameters using a white light interferometer: average roughness (Sa); root mean-square roughness (Sq); skewness (Ssk); and kurtosis (Sku). The radii of the articulating surfaces were measured using a coordinate measuring machine, and were found to be: 2.5, 3.3, 4.2 and 4.7 mm for proximal, and 4.0, 5.1, 5.6 and 6.3 mm for medial components. ANOVA was used to assess the relationship between the component radii and each roughness parameter. Sa, Sq and Ssk correlated negatively with radius (p = 0.001, 0.001, 0.023), whilst Sku correlated positively with radius (p = 0.03). Ergo, the surfaces with the largest radii possessed the better topographical characteristics: low roughness, negative skewness, high kurtosis. Conversely, the surfaces with the smallest radii had poorer topographical characteristics.

Pyrocarbon Proximal Interphalangeal Joint Arthroplasty: Minimum Five-Year Follow-Up.

PURPOSE: To report the outcomes, complications, and survivorship of pyrocarbon proximal interphalangeal joint arthroplasty at a minimum of 5-year follow-up. METHODS: A review of 97 implants in 72 consecutive patients from our joint arthroplasty database was undertaken. Patient demographics, complications, further surgery, and implant revision were recorded. Objective outcome was assessed by grip strength, range of motion, and radiological assessment of alignment, loosening, and subsidence. Subjective outcome was assessed by Patient Evaluation Measure; Quick Disabilities of the Arm, Shoulder, and Hand score; and visual analog scores (0, best; 10, worst) for appearance, satisfaction, and pain. RESULTS: Diagnosis was osteoarthritis in 60 joints, rheumatoid arthritis in 12 joints, psoriatic arthritis in 11 joints, and trauma in 14 joints. The average follow-up was 118 months (range, 60-164 months). The mean arc of motion was 35° (range, 0° to 90°). There was no difference in grip strength between operated and nonoperated side. Of the 97 implants, 36 required additional surgery, of which 14 were revised and 22 required reconstruction around a retained implant. The average Patient Evaluation Measure and Quick Disabilities of the Arm, Shoulder and Hand scores were 33 (range, 10-69) and 35 (range, 0-93), respectively. Mean visual analog scores for pain, satisfaction, and appearance were 2 (range, 0-8), 7 (0-10), and 8 (0-10), respectively. All implants had a lucent line with nearly all classified as either Herren grade 2 or 3. Progressive loosening was seen in 48% of implants. Implant survival as assessed by Kaplan-Meier was 85% at both 5 and 10 years. CONCLUSIONS: Good pain relief and maintenance of preoperative arc of motion was achieved with no major deterioration over time. Most implant revisions were performed within 24 months of the index procedure. Currently progressive loosening was not translated into revision surgery. Implant revision rate was higher than with other prostheses. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Pyrocarbon Metacarpophalangeal Joint Arthroplasty in Noninflammatory Arthritis: Minimum 5-Year Follow-Up.

PURPOSE: To report the outcomes, complications, and survivorship of pyrocarbon metacarpophalangeal joint arthroplasty in noninflammatory arthropathy at a minimum 5-year follow-up. METHODS: A retrospective review of 51 implants in 36 patients was undertaken. Patient demographics, complications, further surgery, and implant revision were recorded. Objective outcome was assessed by grip strength, range of motion, and radiological assessment of alignment, loosening, and subsidence. Subjective outcome was assessed by Patient Evaluation Measure, Quick Disabilities of the Arm, Shoulder and Hand score, and visual analog scores (0, best; 10, worst) for appearance, satisfaction, and pain. RESULTS: There were 35 index and 16 middle fingers. The average follow-up was 103 months (range, 60-172 months). The mean arc of motion was 54° (range, 20° to 80°). There was no difference in grip strength between operated and nonsurgical side. Six implants were revised, and 3 of these required additional surgery. The average Patient Evaluation Measure and Quick Disabilities of the Arm, Shoulder and Hand scores were 27 (range, 10-54) and 29 (range, 0-57), respectively. Mean visual analog scores for pain, satisfaction, and appearance were all 1 with the respective ranges being 0-7, 0-4, and 0-6. Most implants were Herren grade 1 lucency with the remaining 5 proximal and 12 distal implants being grade 2. Mean subsidence in the proximal component was 2 mm (range, 0-4 mm) and 1 mm (range, 0-3 mm) in the distal component. The degree of loosening or subsidence did not correlate with outcome. Implant survival as assessed by Kaplan-Meier was 88% at 10 years. CONCLUSIONS: Good pain relief, a functional range of motion, and high satisfaction were seen in the majority of patients. All implant revisions were performed within 18 months of the index procedure. This may represent technical issues rather than problems with the implant.

The long-term outcome of four-corner fusion.

Introduction Four-corner arthrodesis with excision of the scaphoid is an accepted salvage procedure for scapholunate advanced collapse (SLAC) and scaphoid nonunion advanced collapse (SNAC) and has been performed in our unit for over 20 years. We have undertaken a retrospective review of 116 of these procedures performed in 110 patients between 1992 and 2009. Fifty-eight patients attended for a clinical evaluation, and 29 responded by postal questionnaire. Methods The surgical technique undertaken was standard. That is, through a dorsal approach the scaphoid and tip of the radial styloid were excised. The capitate, lunate, triquetrum, and hamate articular surfaces were then prepared down to bleeding bone. Bone grafts from the scaphoid and radial styloid were then inserted and fixation undertaken. For the latter, various methods were used, including Kirschner (K-)wires, staples, bone screws, but predominantly the Spider plate (Integra Life Sciences, USA). Thereafter the wrist was immobilized for a minimum period of 2 weeks prior to rehabilitation. Results Follow-up was done at a mean of 9 years and 4 months (range 3-19 years). All patients reported a significant improvement in pain relief and ∼50% of flexion extension, although only 40% of radioulnar deviation. Grip strength was again ∼50% of the contralateral side. Most patients reported a significant improvement in function with 87% returning to work. In addition, radiologic evaluation identified 28 patients (31%) who demonstrated ongoing signs of nonunion, particularly around the triquetrum. Fourteen of these (15%) underwent a further procedure, generally with success. Finally, none of the patients demonstrated any arthritic changes in the lunate fossa on follow-up X-ray, and all secondary procedures were undertaken within 2 years of the primary. Discussion This research has demonstrated that four-corner fusion fixed with a circular plate can result in a satisfactory outcome with a reduction in pain, a functional range of motion, and a satisfactory functional outcome. The bulk of the complications appear to occur in the first 2 years after surgery. Thereafter, analysis shows long-term satisfaction with little deterioration. Nonunion, particularly around the triquetrum, continues to be a problem, but it may be that this bone should be excised along with the scaphoid, resulting in a three-part fusion only. Alternatively, a simple capitolunate fusion may be satisfactory.

In vitro wear testing of the PyroCarbon proximal interphalangeal joint replacement: Five million cycles of flexion and extension.

Clinical results of the PyroCarbon proximal interphalangeal joint replacement are inconsistent with various complications reported. To address this, in vitro testing was conducted using finger joint simulators. Two PyroCarbon proximal interphalangeal prostheses were tested in a lubricant of dilute bovine serum to 5 × 10(6) cycles of flexion-extension (90°-30°) with dynamic forces of 10 N applied. At intervals of 3000 cycles testing ceased and a static load of 100 N was applied to simulate gripping. In addition, two 'control' prostheses were immersed alongside the test prostheses to account for lubricant absorption. Wear and roughness averages (Ra) were measured every 1 × 10(6) cycles. Minimal wear for all of the components was measured with a negligible increase in Ra for most of the components. One condyle of one component increased in Ra over the 5 × 10(6) cycles with a value above the recommended 50 nm. Unidirectional marks were visible on the condyle from micrographs, consistent with an abrasive wear mode.

Modified posterior approach for total elbow replacement.

Surgical exposure for total elbow replacement should provide complete visualization of the joint surfaces. The soft tissue reconstruction following replacement often requires protection and can lead to complications such as triceps tendon rupture. We describe a modification of the posterior approach to the elbow that provides optimal exposure and allows early mobilization.

Intermediate outcomes of ulnar head arthroplasty.

PURPOSE: To determine the survivorship and clinical outcomes of ulnar head arthroplasty. METHODS: The study design included a review of medical records and clinical assessment of all patients who had an ulnar head arthroplasty more than 2 years previously. Survivorship of 79 implants in 74 patients was determined. Forty-seven of these patients participated in a clinical review using the Patient Examination Measure, Patient-Related Wrist Examination, Wrightington Wrist Score, and EQ5D to measure outcomes. Analysis of outcomes was performed for diagnostic subgroups (inflammatory arthritis, posttraumatic, osteoarthritis/impingement, and other), primary versus revision surgery, and whether the procedure was performed for ulnar stump instability (related to either a previous Darrach or Sauvé-Kapandji procedure). RESULTS: The 5- and 15-year survival of the implants was 90% for both, with mean follow-up of 7 ± 4 years. Mean age at surgery was 50 ± 13 years (range, 24-76). Mean range of motion was within the functional range and grip strength was 67% that of the contralateral side. Patient satisfaction was generally high, but outcomes scores indicated substantial residual disability. Overall scores were 41 for the Patient Examination Measure, 52 for the Patient-Related Wrist Examination, and 70 for the WWS. Patients in the "other" category had the worst scores for all measures. Patients with prior wrist surgery had poorer outcomes than those for whom the arthroplasty was a primary procedure. Patients with posttraumatic diagnoses had worse EQ5D scores and were less likely to recommend the procedure to others. CONCLUSIONS: Ulnar head arthroplasty had good long-term survival and acceptable patient satisfaction. Substantial disability remained in all groups, with the posttraumatic, "other", and revision groups faring worse. Patients should be counseled about the expected outcomes of this specialized procedure as they pertain to the patient's specific situation. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

The fixation strength of scaphoid bone screws: an in vitro investigation using polyurethane foam.

PURPOSE: To compare the compression strength and pull-apart resistance of 5 single-piece scaphoid bone compression screws (Acutrak, Asnis, Herbert, Herbert-Whipple, and Little Grafter), with those of 2 dual-component screws (Kompressor and TwinFix). METHODS: Two blocks of polyurethane foam were compressed with a screw while held in a tension test machine, with the force measured at full insertion of the screw. The 2 blocks were then pulled apart, and the maximum resistive force was measured. RESULTS: The dual-component screws (Kompressor and TwinFix) gave greater compression force than the single-component screws, with the Kompressor screw giving statistically significantly greater compression than the TwinFix. The pull-apart resistance forces did not show such clear differences. CONCLUSIONS: The Kompressor screw achieves the greatest compressive forces and has one of the highest pull-apart forces. CLINICAL RELEVANCE: When compression and pull-apart resistance are considered, the Kompressor screw has advantages over other methods of scaphoid fixation.

The early migration of a partially cemented fluted pegged glenoid component using radiostereometric analysis.

BACKGROUND: Radiostereometric analysis measures the position of rigid bodies in 3 dimensions with very high precision and can be used to measure early micromotion of glenoid implants. MATERIALS AND METHODS: Radiostereometric analysis was used to measure migration of 11 partially cemented fluted pegged glenoid components in patients with osteoarthritis who underwent shoulder arthroplasty during a 2-year period. Patients were evaluated using the American Shoulder and Elbow Surgeons (ASES) and Constant scores and by a computed tomography (CT) scan at the 2-year follow-up. RESULTS: Migration patterns could be classified into 2 groups: The first group showed little if any migration, the second group rotated by 4° or more as early as 3 months after operation. The maximum total point motion reached up to 2 mm by the 6-month follow-up. At 12 months, the 2 groups could be identified by the presence or absence of focal lucency around the central peg. At the end of 2 years, CT scans were able to classify the same 2 migration patterns by the presence or absence of osseointegration around the cementless central peg of the glenoid implant. The clinical effect of the absence of osseointegration in this novel glenoid component is unknown because both groups had similar clinical results at 2 years. CONCLUSION: Rapid early migration associated with focal lucency and absence of osseointegration was observed in 6 of 11 components. We postulate that lack of initial fixation leads to early movement of the glenoid component and failure of osseointegration.