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 autologous structural bone graft at a minimum of 2 years when used to address significant glenoid bone loss in primary and revision shoulder arthroplasty: a computed tomographic and clinical review.

BACKGROUND: Severe glenoid bone loss remains a challenge in patients requiring shoulder arthroplasty and often requires autogenous bone grafting. The purpose of this study was to assess the integrity of the bone graft at 2 years in a series of primary and revision shoulder replacements where glenoid bone loss was managed using a structural autograft (humeral head or iliac crest bone graft) in combination with a trabecular titanium (TT) implant. METHODS: Ethical approval was sought, and the study has a portfolio study status by the NIHR (17/YH/0318). We contacted patients who had primary and revision shoulder arthroplasty with Lima Axioma TT metal-back glenoid with autologous bone graft and were more than 2 years since their operation. All eligible patients underwent computed tomographic evaluation, clinical review, and scoring. Early failures of composite fixation and patients who had revision procedures were excluded (2 patients). RESULTS: Forty-one patients (43 shoulders) with a mean age of 65 years (range 33-85 years) were reviewed. There were 24 women and 17 men. The average follow-up period was 40 months (range 24-59 months). Primary arthroplasty was performed in 24 shoulders, whereas 19 shoulders had revision arthroplasty. Twenty-five shoulders had reverse shoulder replacement and 18 had anatomic shoulder replacement. Twenty-four shoulders had graft taken from the humeral head, and 19 had iliac crest bone graft, reflecting the number of revisions. We used Wrightington classification for porous metal implant and bone graft incorporation. Satisfactory bone graft incorporation (>50%) was seen in 40 shoulders, and only 3 patients had <50% graft incorporation. The scans at 2 years or later showed no significant deterioration in the bone graft from the early postoperative scans. Average forward elevation improved from 50° (preoperative) to 98° (range 35°-150°). The mean improvement in mean Oxford Shoulder Score was 16 (preoperative, 15; postoperative, 31) and the mean improvement in Constant score improvement was 36 (preoperative, 12; postoperative, 48). The mean postoperative American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) score was 64 (range 30-85). CONCLUSION: The use of TT in conjunction with autologous bone graft provides a reliable method of addressing glenoid bone defects in primary and revision shoulder arthroplasty. This graft-trabecular metal composite has been shown to integrate well and remain largely unchanged over a 2-year period. A stable baseplate is essential in difficult primary and revision arthroplasty situations. The stability of this construct in our series is reflected in the satisfactory outcomes.

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.

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.

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.

Total wrist arthroplasty with the Freedom® prosthesis: a short-term follow-up.

We retrospectively reviewed our series of primary total wrist arthroplasty with the Freedom® prosthesis. The primary outcome measure was revision, and secondary measures included radiographic loosening, pain, complications, movement range, grip strength and patient-reported measures. We reviewed 12 implants in 11 patients (mean age 59 years, range 45-80) with a mean radiological and clinical follow-up of 2.7 and 3 years, respectively. One radial component failed to integrate and was revised at Day 84. Four carpal components demonstrated areas of lucency. There was a statistically significant reduction in pain, and total flexion-extension increased. Despite high patient satisfaction on a ten-point visual analogue scale score (mean 8.7 out of 10), the mean patient-rated wrist evaluation, Quick Disabilities of the Arm, Shoulder and Hand and Patient Evaluation Measure scores were 52, 55 and 53, respectively. The Freedom® implant reduced pain and preserved wrist movement in our patients; however, annual surveillance is recommended due to the high incidence of early carpal component lucency.Level of evidence: IV.

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.

Long-term outcomes of the Universal 2 total wrist replacement: revision and loosening at 10 years and beyond.

The aim of this study was to ascertain the long-term revision rates of the Universal 2 wrist prosthesis in a previously published cohort of patients with rheumatoid arthritis. The time to, and reasons for revision were determined. Radiographs were analysed to determine whether loosening had occurred in the long-term according to the Wrightington zonal classification of loosening. Seventy-eight wrists from the original cohort of 85 wrists could be identified for analysis. The longest follow-up was 16 years and 29 wrists had follow-up beyond 10 years. Seventeen wrists had been revised or were on the waiting list for revision, an overall revision rate of 22%. The 10-year survivorship was 78%. Long-term revision was commonly for periprosthetic loosening with pain and component subsidence. In those with more than 10-year follow-up, significant lucency was seen in 16 carpal components and 15 radial components. Explant analysis showed significant polyethylene wear and we postulate this is the principal reason for component loosening.Level of evidence: IV.

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.

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.

Assessing the required glenoid peg penetration in native scapula when bone graft is used during primary and revision shoulder arthroplasty.

Aims: Achieving purchase in native glenoid bone is essential for the stability of the glenoid baseplate when bone graft is used to address bone loss in both primary and revision shoulder arthroplasty procedures. The aim of this study is to assess the required depth of the baseplate peg in native bone when bone graft is used to result in satisfactory integration. Patients and methods: The CT scans of patients who underwent either primary or revision arthroplasty procedures with bone graft using the SMR Axioma Trabecular Titanium (TT) Metal Backed glenoid system were assessed. We measured the depth of the glenoid peg in native glenoid bone. Measurements were taken by two authors separately. Results: The scans of 53 patients (mean age 68 years) with a minimum follow-up of two years were reviewed. Implants included 12 anatomical and 41 reverse geometry prostheses. There were 17 primaries and 36 revisions: hemiarthroplasties (20) total (14) and reverse (2) implants. Bone grafts were from humeral head (15), iliac crest (34) and allograft (4). The mean depths were 8.8 mm (first assessor) and 9.10 mm (second assessor). The glenoid peg violated the glenoid vault in 32 patients and this did not adversely affect the outcome. There were three failures of implants all of which were aseptic failures and had peg penetration of less than 6 mm. Conclusions: The mean depth of glenoid peg in native bone was 9 mm (variation between 0.2 and 0.52 mm at 95% confidence interval). Aseptic loosening was seen with peg penetration less than 6 mm in native bone. Glenoid vault violation was not associated with loosening.

Excision arthroplasty following shoulder replacement.

Excision arthroplasty of the shoulder is a rarely performed procedure used in cases where replacement of a failed arthroplasty is not feasible. We report four cases of excision arthroplasty following a shoulder replacement, one performed for infection and three for instability. Excision arthroplasty resulted in very poor function with pain improvement in only two cases.

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.

Reverse total shoulder arthroplasty for irreparable rotator cuff tears without arthritis: A systematic review.

INTRODUCTION: Indications for reverse total shoulder arthroplasty (RTSA) have expanded over recent years. Whilst cuff tear arthropathy is an accepted indication, the results of its use in those without arthritis is not clear. The aim of this article is to review the literature on RTSA for massive rotator cuff tears without associated arthritis. METHODS: A systematic review search was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to find all studies with clinical outcomes on RTSA performed for massive irreparable rotator cuff tears (MIRCT) without arthritis. RESULTS: Of the 160 studies produced by the search, a detailed analysis found 11 articles to be included in this review. There was variability in the implant style used and the outcome measures utilised, but all studies found improvement in the outcome following RTSA. Many studies advised judicious use following high complication rates, and caution was advised in those patients with pre-operatively preserved active forward elevation. CONCLUSION: The available evidence suggests that RTSA is a reliable option in older patients with persistent pain and lack of function following MIRCT even without arthritis. However, as outcomes are not significantly worse following failed rotator cuff repair, joint preserving options in the younger age group should be carefully considered in light of the relatively high complication rate associated with RTSA. LEVEL OF EVIDENCE: IV.

MatOrtho Proximal Interphalangeal Joint Arthroplasty via Lateral Approach: Minimum 2-Year Follow-Up.

Background: The MatOrtho implant is a cementless, mobile-bearing surface arthroplasty with a cobalt-chromium metal-on polyethylene articulation designed to treat osteoarthritis of the PIP joint. Early results for the prosthesis inserted through a dorsal approach have demonstrated good pain relief but no significant improvement in range of motion. In an attempt to improve the range of motion the senior author has changed his surgical practice to inserting the MatOrtho implant via a lateral approach. The purpose of this study is to assess the outcome of this change of surgical technique. Methods: Consecutive patients with osteoarthritis who underwent PIPJ replacement surgery via the lateral approach at a single institution, with a minimum follow-up period of 2 years were identified. A visual analogue score was used to assess pain. Grip strength, range of motion and functional outcomes scores were collected. Results: A total of 46 PIP joint arthroplasties were performed in 29 patients. Ten patients were lost to follow-up resulting in 33 PIP joint arthroplasties reviewed in 19 patients. Six implants failed. The mean follow-up time at the final follow-up for the remaining 25 prosthesis was 34.2 months (range 24-52). Range of motion improved from a mean of 37.2 preoperatively to a mean of 57.9 postoperatively. This was statistically significant (p = 0.0007). There was also a significant improvement in pain and functional outcome scores but not for grip strength. Conclusions: The MatOrtho PIPJ replacement delivers significant improvements in pain relief and functional outcome scores, as well as increased range of motion when the surgical procedure is performed through a lateral approach. There are, however, limitations to the use of this implant. Currently we do not consider this implant when there is instability or deformity of the PIP joint preoperatively.

The unicortical sternoclavicular joint reconstruction using synthetic graft.

Sternoclavicular joint injuries represent 5% of all injuries to the shoulder complex. We report a safe and reproducible technique for reconstruction of anterior sternoclavicular joint dislocations, employing a synthetic graft using a unicortical technique with minimal dissection anterior to the joint.

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.