The Use of Navigation or Robotic-Assisted Technology in Total Knee Arthroplasty Does Not Reduce Postoperative Pain.

The use of intraoperative technology (IT), such as computer-assisted navigation (CAN) and robot-assisted surgery (RA), in total knee arthroplasty (TKA) is increasingly popular due to its ability to enhance surgical precision and reduce radiographic outliers. There is disputing evidence as to whether IT leads to better clinical outcomes and reduced postoperative pain. The purpose of this study was to determine if use of CAN or RA in TKA improves pain outcomes. This is a retrospective review of a multicenter randomized control trial of 327 primary TKAs. Demographics, surgical time, IT use (CAN/RA), length of stay (LOS), and opioid consumption (in morphine milligram equivalents) were collected. Analysis was done by comparing IT (n = 110) to a conventional TKA cohort (n = 217). When accounting for demographic differences and the use of a tourniquet, the IT cohort had shorter surgical time (88.77 ± 18.57 vs. 98.12 ± 22.53 minutes; p = 0.005). While postoperative day 1 pain scores were similar (p = 0.316), the IT cohort has less opioid consumption at 2 weeks (p = 0.006) and 1 month (p = 0.005) postoperatively, but not at 3 months (p = 0.058). When comparing different types of IT, CAN, and RA, we found that they had similar surgical times (p = 0.610) and pain scores (p = 0.813). Both cohorts had similar opioid consumption at 2 weeks (p = 0.092), 1 month (p = 0.058), and 3 months (p = 0.064) postoperatively. The use of IT in TKA does not yield a clinically significant reduction in pain outcomes. There was also no difference in pain or perioperative outcomes between CAN and RA technology used in TKA.

The effects of tourniquet on cement penetration in total knee arthroplasty.

PURPOSE: Aseptic loosening is a common cause of implant failure following total knee arthroplasty (TKA). Cement penetration depth is a known factor that determines an implant's "strength" and plays an important role in preventing aseptic loosening. Tourniquet use is thought to facilitate cement penetration, but its use has mixed reviews. The aim of this study was to compare cement penetration depth between tourniquet and tourniquet-less TKA patients. METHODS: A multicenter retrospective review was conducted. Patients were randomized preoperatively to undergo TKA with or without the use of an intraoperative tourniquet. The variables collected were cement penetration measurements in millimeters (mm) within a 1-month post-operative period, length of stay (LOS), and baseline demographics. Measurements were taken by two independent raters and made in accordance to the zones described by the Knee Society Radiographic Evaluation System and methodology used in previous studies. RESULTS: A total of 357 TKA patients were studied. No demographic differences were found between tourniquet (n = 189) and tourniquet-less (n = 168) cohorts. However, the tourniquet cohort had statistically, but not clinically, greater average cement penetration depth [2.4 ± 0.6 mm (range 1.2-4.1 mm) vs. 2.2 ± 0.5 mm (range 1.0-4.3 mm, p = 0.01)]. Moreover, the tourniquet cohort had a significantly greater proportion of patients with an average penetration depth within the accepted zone of 2 mm or greater (78.9% vs. 67.3%, p = 0.02). CONCLUSION: Tourniquet use does not affect average penetration depth but increases the likelihood of achieving optimal cement penetration depth. Further study is warranted to determine whether this increased likelihood of optimal cement penetration depth yields lower revision rates.

Minimum 2-Year Outcomes of a Novel 3D-printed Fully Porous Titanium Acetabular Shell in Revision Total Hip Arthroplasty.

Background: Fully porous acetabular shells are an appealing choice for patients with extensive acetabular defects undergoing revision total hip arthroplasty (rTHA). This study reports on the early outcomes of a novel 3-D printed fully porous titanium acetabular shell in revision acetabular reconstruction. Methods: A multicenter retrospective study of patients who received a fully porous titanium acetabular shell for rTHA with a minimum of 2 years of follow-up was conducted. The primary outcome was rate of acetabular revision. Results: The final study cohort comprised 68 patients with a mean age of 67.6 years (standard deviation 10.4) and body mass index of 29.5 kg/m2 (standard deviation 5.9). Ninety-four percent had a preoperative Paprosky defect grade of 2A or higher. The average follow-up duration was 3.0 years (range 2.0-5.1). Revision-free survivorship at 2 years was 81% for all causes, 88% for acetabular revisions, and 90% for acetabular revision for aseptic acetabular shell failure. Eight shells were explanted within 2 years (12%): 3 for failure of osseointegration/aseptic loosening (4%) after 15, 17, and 20 months; 3 for infection (4%) after 1, 3, and 6 months; and 2 for instability (3%). At the latest postoperative follow-up, all unrevised shells showed radiographic signs of osseointegration, and none had migrated. Conclusions: This novel 3-D printed fully porous titanium shell in rTHA demonstrated good survivorship and osseointegration when used in complex acetabular reconstruction at a minimum of 2 years. Level of evidence: IV, case series.

Does the Use of a Tourniquet Influence Outcomes in Total Knee Arthroplasty: A Randomized Controlled Trial.

BACKGROUND: Intraoperative tourniquet use in total knee arthroplasty (TKA) is a common practice which may improve visualization of the surgical field and reduce blood loss. However, the safety and efficacy associated with tourniquet use continues to be a subject of debate among orthopedic surgeons. The primary purpose of this study is to evaluate the effects of tourniquet use on pain and opioid consumption after TKA. METHODS: This is a multicenter randomized controlled trial among patients undergoing TKA. Patients were preoperatively randomized to undergo TKA with or without the use of an intraoperative tourniquet. Frequency distributions, means, and standard deviations were used to describe baseline patient demographics (age, gender, race, body mass index, smoking status), length of stay, surgical factors, visual analog scale pain scores, and opioid consumption in morphine milligram equivalents. RESULTS: A total of 327 patients were included in this study, with 166 patients undergoing TKA without a tourniquet and 161 patients with a tourniquet. A statistically significant difference was found in surgical time (97.87 vs 92.98 minutes; P = .05), whereas none was found for length of stay (1.73 vs 1.70 days; P = .87), postop visual analog scale pain scores (1.73 vs 1.70; P = .87), inpatient opioid consumption (19.84 vs 19.27 morphine milligram equivalents; P = .74), or outpatient opioid consumption between the tourniquet-less and tourniquet cohorts, respectively. There were no readmissions in either cohort during the 90-day episode of care. CONCLUSION: Utilization of a tourniquet during TKA has minimal impact on postoperative pain scores and opioid consumption when compared with patients who underwent TKA without a tourniquet.

Short-term outcomes with the REDAPT monolithic, tapered, fluted, grit-blasted, forged titanium revision femoral stem.

AIMS: Although good clinical outcomes have been reported for monolithic tapered, fluted, titanium stems (TFTS), early results showed high rates of subsidence. Advances in stem design may mitigate these concerns. This study reports on the use of a current monolithic TFTS for a variety of indications. METHODS: A multi-institutional retrospective study of all consecutive total hip arthroplasty (THA) and revision total hip arthroplasty (rTHA) patients who received the monolithic TFTS was conducted. Surgery was performed by eight fellowship-trained arthroplasty surgeons at four institutions. A total of 157 hips in 153 patients at a mean follow-up of 11.6 months (SD7.8) were included. Mean patient age at the time of surgery was 67.4 years (SD 13.3) and mean body mass index (BMI) was 28.9 kg/m2 (SD 6.5). Outcomes included intraoperative complications, one-year all-cause re-revisions, and subsidence at postoperative time intervals (two weeks, six weeks, six months, nine months, and one year). RESULTS: There were eight intraoperative complications (4.9%), six of which were intraoperative fractures; none occurred during stem insertion. Six hips (3.7%) underwent re-revision within one year; only one procedure involved removal of the prosthesis due to infection. Mean total subsidence at latest follow-up was 1.64 mm (SD 2.47). Overall, 17 of 144 stems (11.8%) on which measurements could be performed had >5 mm of subsidence, and 3/144 (2.1%) had >10 mm of subsidence within one year. A univariate regression analysis found that additional subsidence after three months was minimal. A multivariate regression analysis found that subsidence was not significantly associated with periprosthetic fracture as an indication for surgery, the presence of an extended trochanteric osteotomy (ETO), Paprosky classification of femoral bone loss, stem length, or type of procedure performed (i.e. full revision vs conversion/primary). CONCLUSION: Advances in implant design, improved trials, a range of stem lengths and diameters, and high offset options mitigate concerns of early subsidence and dislocation with monolithic TFTS, making them a valuable option for femoral revision. Cite this article: Bone Joint J 2020;102-B(2):191-197.

Novel, Patient-Specific Instruments for Acetabular Preparation and Cup Placement.

INTRODUCTION: Patient-specific implants and instruments (PSI) have been used in both knee and shoulder replacements due to the perceived benefits of improved surgical accuracy and efficiency. The proposed benefits of using a PSI in total hip arthroplasty (THA) are numerous and include reduction of operative time and improved mechanical and anatomical alignment leading to increased implant longevity, increased stability, and clinical outcomes. We describe a novel patient-specific instrumentation and a surgical method that may improve directed resection of acetabular bone and accurate cup placement during THA. MATERIALS AND METHODS: In this cadaveric study, 14 acetabuli were used. Pre-operative CT or MRI scans were obtained as part of the acetabular jigs Bullseye Hip Replacement Instruments® (Bullseye Hip Replacement, LLC, Las Vegas, Nevada) protocol. Two senior hip surgeons performed all the operations in accordance to the PSI technique. Post-operative CT scans were obtained and acetabular cup orientation was measured by two independent radiologists. RESULTS: Fourteen acetabuli were implanted using the Bullseye Hip Replacement Instruments®. Acetabular cup anteversion angle as measured on post-operative CT images averaged, for all 14 acetabuli, 15.50. Acetabular cup abduction/inclination angle as measured on post-operative CT images averaged 35.9°. All implanted components' size/diameter matched the preoperative surgical planned implant size. CONCLUSION: The Bullseye Hip Replacement Instruments® show good reproducible acetabular cup placement in both anteversion and abduction angles, and accurate sizing of the acetabular component. .

Perioperative Complications in Patients With Inflammatory Arthropathy Undergoing Total Hip Arthroplasty.

BACKGROUND: Limited information exists comparing the short-term complications of the different inflammatory arthropathies (IAs) after total hip arthroplasty (THA). Our objectives were to (1) compare perioperative complications and (2) determine the most common complications between the different IA subtypes compared with patients with osteoarthritis (OA) undergoing primary THA. METHODS: The Nationwide Inpatient Sample was used to identify 2,102,238 patients undergoing elective, unilateral THA between 2002 and 2011. Of these, 86,671 (4%) had an IA, including rheumatoid arthritis (RA), psoriatic arthritis, juvenile idiopathic arthritis (JIA), ankylosing spondylitis (AS), and systemic lupus erythematosus (SLE). Preoperative diagnosis, comorbidities, and postoperative complications were determined using International Classification of Disease Clinical Modification version 9 codes. The prevalence of in-hospital medical and orthopedic complications was compared between patients with an IA and OA. RESULTS: When compared with patients with OA, patients with RA, JIA, SLE, and AS had significantly more inpatient medical and orthopedic complications immediately after THA (P < .01). Patients with JIA had the highest orthopedic complication rate (2.8%). Specific orthopedic complications by subtype included wound dehiscence for RA and AS periprosthetic fractures for JIA and increased mortality for SLE patients. There were no significant differences in medical or orthopedic complications seen in patients with psoriatic arthritis. CONCLUSION: Differences exist in postoperative inpatient medical and orthopedic complications among patients with different types of IAs after THA. Our results point out the importance of preoperative optimization in patients with IA and monitoring for selective postoperative complications.

How Much Do Patients Value Total Hip and Knee Arthroplasty? A Prospective, Multicenter Study.

BACKGROUND: With increasing health care expenditures, reform has largely focused on cost containment, particularly in elective procedures such as total hip and knee arthroplasty (THA and TKA, respectively). The primary objective of this study is to determine what financial value patients place on these highly successful procedures. METHODS: An anonymous survey was administered to 670 patients at 4 different institutions (2 private practice and 2 academic centers) in the outpatient setting over a 15-month period. Patients were asked what reimbursement a surgeon should receive for a primary total joint arthroplasty (TJA), their perception of how much Medicare actually reimburses for TJA, how much they would pay out of pocket for the procedure, and their opinion of current Medicare reimbursement rates. RESULTS: Of the 557 patients who participated in the survey (83% response rate), patients on average felt that orthopedic surgeons should be reimbursed $27,430 for a THA and $19,830 for a TKA. Patients would be willing to pay a significant amount of out-of-pocket costs for their procedure, mean of $14,397 for THA (50.3% of total costs) and $12,797 for TKA (46.3% of total costs). Although patients in private practice groups had higher education and household income (P < .001), patients in academic centers would be willing to pay more out-of-pocket costs ($15,922 vs $5782, P = .034 for THA, $14,419 vs $4556, P = .052 for TKA). CONCLUSION: Patients in both private practice and academic centers feel that surgeons are underpaid for primary THA and TKA. As controversy continues to surround orthopedic surgeons' participation in Medicare, many patients are still willing to pay a significant amount of out-of-pocket expenses for TJA.

Posterior Stabilized Polyethylene Inserts in Total Knee Arthroplasty: A Retrieval Study Comparing Conventional to High-Flexion Designs.

BACKGROUND: High-flex (HF) total knee arthroplasties are modified posterior-stabilized (PS) implants designed to accommodate greater flexion. METHODS: We examined differences between HF and PS retrieved tibial inserts with regard to polyethylene surface damage. Twenty HF inserts from each of 3 manufacturers were matched using patient demographics with 20 PS inserts from the same manufacturers. Ranges of motion between matched patients were not different. RESULTS: Based on subjective damage scores, no differences were detected between HF and PS groups. Differences were found, however, among manufacturers, consistent with design approaches taken for PS and HF implants. CONCLUSION: In our series, high flexion did not influence damage, although this was likely influenced by the fact that few HF patients in our study had larger range of motions than their PS counterparts.

Perioperative Complications in Patients with Inflammatory Arthropathy Undergoing Total Knee Arthroplasty.

Little data exists comparing acute post-operative outcomes in patients with different types of inflammatory arthritis (IA) after undergoing a total knee arthroplasty (TKA). Our objectives were to compare perioperative complications and determine the most common complications between the different IA subtypes compared with patients with osteoarthritis undergoing primary TKA. We found significant differences when comparing complications within the different subtypes of IA. RA patients, despite having a greater number of comorbidities had a reduced rate of medical complications postoperatively compared to the OA cohort. All of the inflammatory subtypes had a higher rate of orthopedic complications postoperatively compared to the OA group except for patients with AS. However, ankylosing spondylitis had the highest mortality rate as well as medical complication rate among the subtypes.

The Position of the Patella and Extensor Mechanism Affects Intraoperative Compartmental Loads During Total Knee Arthroplasty: A Pilot Study Using Intraoperative Sensing to Guide Soft Tissue Balance.

UNLABELLED: The achievement of a well-balanced total knee arthroplasty is necessary for long-term success. We hypothesize that the dislocation of the patella during surgery affects the distribution of loads in the medial and lateral compartments. Intraoperative load sensors were used to record medial and lateral compartment loads in 56 well-balanced TKAs. Loads were recorded in full extension, relaxed extension, at 45 and 90° of flexion at full gravity-assisted flexion, with the patella in four different positions: dislocated (everted and not), located, and located and secured with two retinacular sutures. The loads in the lateral compartment in flexion were higher with a dislocated patella than with a located patella (P<0.001). A lateralized extensor mechanism artificially increases in the lateral compartment loads in flexion during TKA surgery. Instruments that allow intraoperative soft tissue balance with the patella in a physiologic position are more likely to replicate postoperative compartment loads. LEVEL OF EVIDENCE: II (prospective comparative study).

Acetabular fractures converted to total hip arthroplasties in the elderly: how does function compare to primary total hip arthroplasty?

OBJECTIVES: Little data exist regarding the outcomes of total hip arthroplasty (THA) after acetabular fracture treatment failure. We hypothesize that these patients achieve a lower level of function than those who undergo primary THA for osteoarthritis (atraumatic). DESIGN: Retrospective review. Control group consisted of sequential patients who underwent a primary THA for osteoarthritis and were 60 years or older at the time of surgery. SETTING: Level I Academic Trauma Center. PATIENTS: One hundred seventy-one patients older than 60 years when they sustained an acetabular fracture were included in this study. Seventeen (10%) patients were converted to THA. Control patients were treated with primary THA for osteoarthritis. MAIN OUTCOME MEASURES: Musculoskeletal function assessment scores and Harris Hip scores were obtained after a minimum follow-up of 2 years. RESULTS: Thirteen patients underwent open reduction and internal fixation, 3 underwent nonoperative treatment, and 1 received an acute THA. The most common fracture patterns converted to THA were associated both column (n = 5) and posterior column with posterior wall (n = 5). The average time to conversion to THA was 35 months. When compared with controls, patients who had THA after an acetabular fracture had significantly higher Musculoskeletal Function Assessment scores and significantly lower Harris Hip scores, indicating worse level of function. CONCLUSIONS: Patients who undergo THA after acetabular fracture have significantly worse functional outcome scores when compared with patients who undergo a primary THA for osteoarthritis. LEVEL OF EVIDENCE: Prognostic level III.

Arthroscopic treatment of anterosuperior rotator cuff tears.

This study evaluated pre- and postoperative clinical and structural outcome data on anterosuperior rotator cuff tears involving the supraspinatus and subscapularis treated by arthroscopic methods. Between June 2006 and October 2007, a total of 155 consecutive patients underwent an arthroscopic repair for a supraspinatus or supraspinatus and infraspinatus (superior) rotator cuff tear. Of these, 44 (28%) were identified on preoperative imaging to have involvement of the subscapularis. Confirmation of subscapularis tears occurred during arthroscopic repair of the superior rotator cuff. If the subscapularis was found to be torn, it was documented, and an arthroscopic repair was performed. Postoperative clinical and radiographic outcomes were assessed with the belly press and lift-off tests, range of motion, strength, pain score, Constant score, and either a magnetic resonance imaging arthrogram or a computed tomography arthrogram at an average of 15 months postoperatively. Failure was determined based on rotator cuff integrity on radiologic studies. Sixteen of the 44 anterosuperior rotator cuff tears identified on preoperative imaging were found to have a full-thickness subscapularis tear requiring repair on arthroscopic examination. On preoperative imaging, subscapularis tears were all either grade 1 or grade 2 (no complete grade 3 tears). Mean follow-up was 16.9 months (range, 13-24 months). Compared with preoperative values, significant postoperative improvements occurred in Constant scores, forward flexion, strength, and pain scores (P<.01). Patients also showed significant improvements in both the lift-off and belly press tests (P<.001). Mean postoperative patient satisfaction was 7.9 (range, 5-10) with 10 (59%) of 17 patients being extremely satisfied. Two of the 17 patients with an anterosuperior rotator cuff tear had confirmed retears of the supraspinatus (1 partial and 1 full-thickness) with no radiographic evidence of retear of any of the subscapularis repairs at most recent follow-up.

Congenital stenosis and adjacent segment disease in the cervical spine.

Symptomatic adjacent segment disease (ASD) after anterior cervical fusion (ACF) is reported in 25% of patients at 10 years postoperatively. Debate continues as to whether this degeneration is due to the natural history of the disk or the changed biomechanics after ACF. This study explored whether congenital stenosis predisposes patients to an increased incidence of ASD after ACF. A retrospective review of 635 patients with myelopathy or radiculopathy was performed; 364 patients had complete records for review. Patients underwent 1- to 5-level ACF (94 one-level, 145 two-level, 79 three-level, 45 four-level, and 1 five-level). Radiographs were evaluated for bony congenital stenosis using validated parameters, and ASD was measured according to Hilibrand's criteria and correlated with symptomatic ASD. Congenital stenosis was found in 21.7% of patients and radiographic ASD in 33.5%, with a significant association between these parameters. However, symptomatic ASD occurred in 11.8% of patients; no association between congenital stenosis and symptomatic ASD or myelopathy and ASD was found. Clinical results demonstrated excellent or good Robinson scores in 86.2% of patients and Odom scores in 87% of patients. Despite mostly excellent to good outcomes, symptomatic ASD is common after ACF. Although congenital stenosis appears to increase the incidence of radiographic ASD, it does not appear to predict symptomatic ASD.

CORR Insights: Locking buttons increase fatigue life of locking plates in a segmental bone defect model.

This CORR Insights™ is a commentary on the article "Locking Buttons Increase Fatigue Life of Locking Plates in a Segmental Bone Defect Model" by Tompkins et al. available at DOI 10.1007/s11999-012-2664-1 .

PI3Kγ deletion reduces variability in the in vivo osteolytic response induced by orthopaedic wear particles.

Orthopedic wear particles activate a number of intracellular signaling pathways associated with inflammation in macrophages and we have previously shown that the phosphoinositol-3-kinase (PI3K)/Akt pathway is one of the signal transduction pathways that mediates the in vitro activation of macrophages by orthopedic wear particles. Since PI3Kγ is primarily responsible for PI3K activity during inflammation, we hypothesized that PI3Kγ mediates particle-induced osteolysis in vivo. Our results do not strongly support the hypothesis that PI3Kγ regulates the overall amount of particle-induced osteolysis in the murine calvarial model. However, our results strongly support the conclusion that variability in the amount of particle-induced osteolysis between individual mice is reduced in the PI3Kγ(-/-) mice. These results suggest that PI3Kγ contributes to osteolysis to different degrees in individual mice and that the mice, and patients, that are most susceptible to osteolysis may be so, in part, due to an increased contribution from PI3Kγ.

Early structural and functional outcomes for arthroscopic double-row transosseous-equivalent rotator cuff repair.

BACKGROUND: The arthroscopic double-row transosseous-equivalent (TOE) rotator cuff repair is growing in popularity. The current body of literature supports this technique; however, the number of patients in these studies is relatively small. The authors conducted this study to learn more about the natural history of this construct in a large sample of patients. HYPOTHESIS: The double-row TOE rotator cuff repair will have an acceptable structural failure rate with improved clinical outcomes at 1-year follow-up. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Between June 2006 and October 2007, 225 patients underwent an all-arthroscopic rotator cuff repair at 2 surgical centers. A total of 155 TOE primary rotator cuff repairs were performed, and 154 of these patients met the inclusion criteria. Assessment of structural integrity was based on evaluation of postoperative magnetic resonance imaging or computed tomography arthrogram at a minimum of 12 months after surgery. The Constant scores, visual analog pain scale, range of motion, strength, and complications were the clinical outcomes analyzed for the study. Seventeen patients (of 154) had postoperative shoulder stiffness at follow-up. RESULTS: The 154 patients were clinically and radiologically evaluated at a mean of 15 months postoperatively (range, 12-26.1 months). The study included 47 small (30.5%), 89 large (57.1%), and 19 massive (12.3%) rotator cuff tears. Analysis of postoperative imaging demonstrated that 92%, 83%, and 84% of the small, large, and massive rotator cuff tears, respectively, were intact. The mean Constant score improved from 44.42 points preoperatively to 80.47 points postoperatively (P < .001). The mean preoperative pain score improved from 3.83 to 12.77 (P < .001) postoperatively. The mean forward flexion improved from 123.06° preoperatively to 162.39° postoperatively (P < .001). Seventeen patients (of 154) had postoperative shoulder stiffness at follow-up. CONCLUSION: The short-term results of this study indicate that the clinical outcomes and structural integrity of TOE double-row rotator cuff repair (the suture-bridge technique) have results that compare favorably with those reported for other double-row suture anchor techniques employed in rotator cuff repairs. Long-term follow-up will be necessary to determine if the durability of these repairs and the structural integrity of these constructs maintain their performance over time.

A new approach to improving the tissue grip of the medial-row repair in the suture-bridge technique: the "modified lasso-loop stitch".

The double-row rotator cuff repair has proved to be biomechanically superior to the single-row technique. However, this has not been shown clinically. At the moment, all the methods proposed for medial-row suturing in the suture-bridge technique recommend a mattress suture or a simple stitch. The lasso-loop stitch has been proposed as a technique to improve tissue grip and has been used in open rotator cuff repairs, in biceps tenodesis, and in the Bankart procedure. We propose a method in which a modified version of this stitch can be used to repair the medial row of a double-row repair. In the "modified lasso-loop stitch," a circumferential stitch is constructed over the posteromedial and anteromedial anchor. This stitch exerts an appropriate amount of radial compression on the encased tendon as the tails of the posteromedial and anteromedial suture are fixed to the anterolateral anchor. Through this technique, the reduction force is augmented and a compression force is created, thus allowing restoration of the rotator cuff footprint. This technique provides a strong cuff-suture interface while appropriate tensioning of the modified lasso-loop stitch allows minimal strangulation of the tendon. This technique has been shown to work with and without a knot.

Primary total shoulder arthroplasty performed entirely thru the rotator interval: technique and minimum two-year outcomes.

BACKGROUND: Total shoulder replacement (TSR) is an effective treatment of shoulder arthritis. However, subscapularis insufficiency after TSR remains a significant cause of poor outcomes after shoulder arthroplasty. We describe a novel technique for performing a TSR entirely through the rotator interval (RI) without tenotomy of the subscapularis or supraspinatus tendons and without dislocating the shoulder using the superior approach. MATERIAL AND METHODS: We prospectively followed up 22 patients who underwent this procedure. Subjective patient satisfaction, Constant, Simple Shoulder Test (SST) scores, and range of motion (ROM) were evaluated preoperatively and postoperatively at a mean follow-up of 29 months. Radiographic findings are also presented. RESULTS: Subjective patient satisfaction results were good in 5 of 17 patients and excellent in 12. Patients also had significant increases in Constant, visual analog scale, SST, and ROM scores. One patient was excluded due to a traumatic periprosthetic fracture (fall), 3 patients refused to return for follow-up, and 1 patient was lost to follow-up. Postoperative results included nonanatomic humeral head osteotomies in 6, residual inferior humeral neck osteophytes in 8, and the humeral head prosthesis was undersized in 5. CONCLUSIONS: The patients had favorable clinical outcomes. This technique for TSR demonstrates that in the postoperative period, patients can immediately partake in unrestricted physical therapy. This study reports the clinical outcomes of this technique for TSR with a minimum of 2 years of follow-up. LEVEL OF EVIDENCE: Level 4; Case series, treatment study.

Genetic abnormalities associated with nodal metastasis in head and neck cancer.

BACKGROUND: Lymphatic metastasis represents the single most important clinical prognostic factor in head and neck squamous cell carcinoma (HNSCC), but underlying genetic mechanisms remain ill defined. Genetic differences between primary carcinomas and their corresponding metastases might form a key to understanding the metastatic phenotype. In this study we aimed to characterize such differences using a genome-wide screening measure. METHODS: Four human cell lines (MDA-686tu, MDA-686Ln, MDA-1386tu, MDA-1386Ln) derived from primary tumor and synchronous lymph node metastasis of two cases of metastatic HNSCC were subjected to comparative genomic hybridization (CGH) by differentially labeling DNA from tumor tissue and normal tissue with fluorescent agents. The labeled DNAs were simultaneously hybridized onto normal metaphase chromosomes. In addition, modified CGH was performed by directly hybridizing labeled primary tumor DNA against differentially labeled metastatic tumor DNA, allowing the direct detection of copy number differences in individual pairs. Image analysis for fluorescence intensity along the entire length of each metaphase chromosome allowed generation of a color ratio, which was used to detect copy number changes. RESULTS: In both cases, significant overlap was found between chromosomal aberrations present in the primary tumor and the corresponding nodal metastasis. However, several abnormalities differentiated primary tumors from their metastases. Modified CGH identified several genetic aberrations that were not detectable with the conventional CGH analysis. Gains at chromosomes 10p11-12 and 11p and deletions at chromosomes 4q22-31, 9p13-24, and 14q differentiated nodal metastases from the corresponding primary tumors in both cases. CONCLUSIONS: The combination of conventional and modified CGH analyses facilitates the identification of DNA copy number changes that might be involved in the development of a metastatic phenotype. Future research should aim at the identification of the genes involved at the identified sites of chromosomal aberration.