Semi-constrained Prosthesis Research Articles

Two-Year Outcomes After Total Ankle Replacement With a Novel Fixed-Bearing Implant By a Single Surgeon Non-Inventor

Total ankle arthroplasty continues to gain popularity amongst surgeons and patients as an alternative to arthrodesis. Historically the designs of early implants were plagued with complications and frequently abandoned. Since that time the procedure and materials have undergone significant advancements in both surgical approach as well as design and function of the available implants. In this study, 40 consecutive patients who received a semiconstrained prosthesis with a unique fixed-bearing polyethylene insert were identified. Minimum follow-up was 2 y. Demographic, social, and past medical data was retrospectively reviewed. Concomitant procedures were also recorded. Radiographic analysis included lateral ankle radiograph postoperative range of motion (ROM) with maximum dorsiflexion and maximum plantarflexion weight bearing at the most recent clinic visit. Clinical outcomes included VAS, FFI, and AOFAS scores. Lateral radiographs taken in the office at a minimum 2-y follow-up showed mean maximum dorsiflexion of 11.8 degrees and plantarflexion of 13.9 degrees. VAS, FFI, and AOFAS scores improved from 8.1, 92.9, and 44.8 to 1.4, 15.3, and 90.1 postoperatively, respectively. A total of 2.5% (n = 1) required revision surgery for poly failure, and 5.0% (n = 2) underwent local wound care in the office setting postoperatively and healed without complications. Overall survivorship was 97.5% at the minimum follow-up of 2 y. In conclusion, similar studies have reported survivorship from 90% to 100% with modern ankle implants in short to mid-term follow-up. Although this is a small sample size, our data shows a 97.5% survivorship at 2 y postoperatively with favorable patient-reported statistically significant functional outcome scores, and ankle range of motion consistent with existing literature.

A New Hinge Prosthesis Offers Ease of Use and the Ability to Retain the Revision Tibial Baseplate.

Total knee arthroplasty (TKA) is a widely practiced surgical procedure, with its efficacy underscored by the increasing number of patients benefiting from it. As primary TKAs rise, the orthopaedic community must prepare for a surge in complex primary and revision knee arthroplasties in the future. While most revisions use non-constrained or semi-constrained prostheses, certain scenarios require a fully constrained (hinge) prosthesis to address major ligamentous and/or bone loss. Over time, hinge designs have evolved, but outcomes with these designs have been mixed. To help address challenges seen with some earlier designs, a new modular revision solution has been designed for both primary and revision surgeries. This system has a new revision baseplate that has compatibilities with varying distal femoral components and introduces an enhanced hinge mechanism. This paper aims to explore the evolution of hinge designs, elaborate on the surgical workflows and intended compatibilities of this new revision hinge system in six different scenarios, and discuss its various potential advantages.

Treatment of neuropathic unstable knee osteoarthritis by a condylar, rotating-hinge prosthesis with cementless pentagonal stem: a case series

Total knee arthroplasty (TKA) in the neuropathic unstable knee (NUK) setting is classically a challenging orthopedic problem due to intraoperative technical difficulties and a higher frequency of periprosthetic complications. More recently, satisfactory results have been reported using improved constraints, stems and revision-type TKA components. The study aims to present long-term results of a small case series with NUK osteoarthritis reconstructed by a condylar, semi-constrained prosthesis with a polygonal, hydroxyapatite-coated (HA-coated) press-fit stem. From 2009 through 2010, three knees in three patients with advanced NUK arthropathy underwent TKAs in our institution using the PENTA® prosthesis. The average age at surgery was 44 years (32–58). The patients were followed up for a mean period of 124 months (120–128). The etiology of NUK was determined to be poliomyelitis sequela in 2 cases and spinal cord injury in one case. Functional outcomes were assessed with Knee Society (KS) Knee and Function Scores, and radiological outcomes were evaluated with ISOLS radiographic implant scores. Patients were monitored for complications clinically and radiologically. KS knee scores improved from a mean of 12,3 (0–37) preoperatively to 71,3 (65–77) and KS function scores improved from a mean of 1,7 (0–5) preoperatively to 68,3 (55–80) at the latest follow-up. Radiological outcomes were excellent according to ISOLS scores, and no complications were observed. Although this is a small case series, the significant improvement in functional scores, excellent radiological outcome, and implant survival at the end of a long follow-up period warrants TKA with a semi-constrained hinged implant in the setting of NUK. PENTA® prosthesis offers a good choice of implant with its hydroxyapatite-coated, press-fit, pentagonal stem and precisely designed rotating hinge.

Clinical and Radiographic Outcomes of Total Elbow Arthroplasty Using a Semi-constrained Prosthesis with a Triceps-preserving Approach over a Minimum Follow-up Period of 4 Years.

Complications related to triceps after total elbow arthroplasty (TEA) have become a major surgical concern. The triceps-preserving approach has the advantage of not disturbing the insertion of triceps but is disadvantaged by the reduced exposure of the elbow joint. The aim of this study was to investigate the clinical and radiological outcomes of TEA with a triceps-preserving approach and to compare the outcomes of TEA to treat arthropathy with that of TEA to treat acute distal humerus fracture. From January 2010 to December 2018, 23 patients undergoing primary TEAs were retrospectively reviewed with a mean follow-up time of 92.6 months (range, 52-136months). Each TEA was performed using the triceps-preserving approach with a semi-constrained Coonrad-Morrey prosthesis. Patient demographics, range of motion (ROM), pain visual analogue scale (VAS), and triceps strength (Medical Research Council [MRC] scale) were compared before and after surgery. The Mayo Elbow Performance Score (MEPS), Disabilities of the Arm, Shoulder, and Hand (DASH) score, radiographic outcome, and complications were evaluated at follow-up. In total, seven males and 16 females were included in this study, with a mean age of 66.1 years (range:46-85 years). By the last follow-up, pain had been significantly relieved in all patients. The average MEPS in the arthropathy group and fracture group were 90.8 ± 10.3 points (range: 68-98 points) and 91.7 ± 0.4 (range: 76-100 points), respectively. The average DASH of the arthropathy group and fracture group was 37.3 ± 18.8 points (range: 18-52 points) and 38.4 ± 20.1 (range: 16-60 points). At the last follow-up after surgery, the mean flexion arcs in the arthropathy group and fracture group were 100.4° ± 24.1° and 97.8° ± 28.1°, respectively. The mean pro-supination arcs in the arthropathy group and fracture group were 142.4° ± 15.2° and 139.2° ± 17.5°, respectively. There were no significant differences in clinical outcomes between the two groups (P≥ 0.05). Triceps strength was normal (MRC grade V) in 15 elbows and good in eight elbows. None of the cases experienced weakness of the triceps strength, infection, periprosthetic fractures, or prosthesis breakage. The clinical and radiographical outcomes of TEA with the triceps-preserving approach were satisfactory in patients with distal humerus fracture, osteoarthritis and rheumatoid arthritis.

Twenty-Year Experience With Primary Distal Radioulnar Joint Arthroplasty From a Single Institution

The use of implant arthroplasty in the distal radioulnar joint is increasing. Two main types of implants are commonly used, ulnar head prosthesis (UHP) and hemi or semi-constrained total distal radioulnar joint arthroplasty. The literature consists mainly of small patient series. The purpose of this study was to examine our long-term outcomes of distal radioulnar joint arthroplasty. Patient data were collected in a patient registry from 2000 to 2019. The follow-up included radiographic examination, physical examination, Mayo Wrist Scores, pain level, range of motion, and grip strength. Reoperations were recorded. The implants were a semi-constrained prosthesis and a metallic UHP. The mean age at surgery was 50 years. Patient demographics were similar, but the semi-constrained group had a higher preoperative percentage of instability (85 vs 52 percent). The median follow-up time was 30 months for the semi-constrained implants group and 102 months for the UHP group. A total of 53 primary semi-constrained total joint arthroplasties and 102 UHPs were included. The grip strength and Mayo Wrist Score improved for both the implant groups. Pain reduced in 76% of the patients. Supination improved for the semi-constrained total joint arthroplasty group. Lifting capacity was better in the semi-constrained total joint arthroplasty patients. The unadjusted reoperation rate was 23% for the semi-constrained implants group and 34% for the UHP group. Twenty-two implants were bilateral; these had comparable results to unilateral implants. Kaplan-Meier survival curves demonstrated 94% survival rate for the semi-constrained implants group and 87% survival for the UHP group after 5 years. The risk factors associated with reoperation for the combined implant group included younger age at surgery, previous wrist surgery, ulnar shortening, and wrist fusion. Distal radioulnar joint arthroplasty improved functional outcomes in both the implant groups, but reoperations were frequent. The semi-constrained implants group had better lifting capacity. The bilateral implants had comparable outcomes to the unilateral implants. Therapeutic IV.

Short-term Outcomes of Semi-constrained Implants in Patients With Complex Primary Total Knee Arthroplasty

Background: Semi-constrained implants are developed to reduce the detrimental impact of constrained implants in patients with complex primary total knee arthroplasty (TKA). However, the outcomes of TKA using semi-constrained implants are mainly unknown. Objectives: This study aims to report the short-term outcomes and complications of primary TKA in patients managed with a semi-constrained implant. Methods: Twenty-three patients (33 knees) who underwent TKA with semi-constrained implants were included in this study. The outcomes of patients were evaluated radiographically and clinically. Clinical evaluation was performed using the knee society score (KSS) and oxford knee score (OKS) at 6 and 12 months. The subjective satisfaction of the patients was also evaluated at 6 and 12 months using yes/no questions. Postoperative complications were inspected through the patient’s medical records. Results: The study population included six men and 17 women with a mean age of 70.7±7.6 years. The mean follow-up of the patients was 12.5±4.8 months. The average postoperative ‎tibiofemoral alignment was 0.26±1.1º of valgus (ranging from 3º of valgus to 2º of varus). The mean KSS of the patients were 93.8±8.1 and 94.7±8.3 at 6 and 12 months, respectively. The mean OKS of the patients were 43.6±3.7 and 44.1±3.8 at 6 and 12 months, respectively. All patients were satisfied with the surgery at 6 and 12 months. No postoperative complications were recorded during the follow-up period. Conclusion: The use of a semi-constrained prosthesis is safe and effective as a primary implant in TKA ‎patients having severe deformity or ligamentous laxity.

Midterm Functional Outcome of the Linked Semiconstrained Distal Radioulnar Joint Prosthesis.

Background A painful unstable distal radioulnar joint (DRUJ) can seriously compromise hand and wrist function. The semiconstrained prosthesis was developed to restore DRUJ function. To date, most outcome reports are coauthored by the designer. Questions Does independent reporting confirm the promising results of the semiconstrained DRUJ prosthesis? Are complication and failure rates acceptable? Patients and Methods We evaluated patients with the semiconstrained DRUJ implant and a minimum follow-up of 2 years. We monitored patient satisfaction and function with functionality questionnaires and measured wrist range of motion, grip, and key pinch strength. Statistical analysis was done using descriptive statistics, Pearson correlation coefficients, linear and logistic regression. Results We included 41 patients with 42 implants. Mean follow-up was 46 months (range: 24-102 months). Eighty percent of wrist had undergone previous surgery. We found a mean pronation of 83 degrees (0-90 degrees), supination of 70 degrees (0-90 degrees), flexion of 42 degrees (0-90 degrees), extension of 49 degrees (0-90 degrees), ulnar deviation of 24 degrees (0-60 degrees), and radial deviation of 14 degrees (0-40 degrees). Grip and key pinch strength were 20.1 (1-50 kg) and 6 kg (1-12 kg), respectively. Average patient-rated wrist and hand evaluation score was 42.7 (0-95), disabilities of the arm, shoulder and hand score was 38 (0-88), and visual analog scale score was 3.6 (0-8). We found a 43% complication rate (mostly minor: ulnar or radial tendinopathy, temporary hypoesthesia) with 24% reoperation and 92% prosthesis survival rate. Conclusion The linked semiconstrained DRUJ prosthesis has its value in the surgical treatment of DRUJ failure. Currently, most implants are used in secondary surgery and multioperated wrists. More research is required to assess the value of the DRUJ prosthesis as a primary procedure. Level of evidence This is a level IV, therapeutic study.

Salvage of Painful Porous Coated Stem Ulnar Head Prosthesis With Semiconstrained Distal Radioulnar Joint Arthroplasty

To determine the functional outcome and complications after conversion from a painful and unstable ulnar head prosthesis to a semiconstrained distal radioulnar joint arthroplasty. We conducted a retrospective review of 11 ulnar head prostheses in 10 patients with porous coated stems that were revised to semiconstrained prostheses. The median age of the patients was 47 years. The median number of wrist surgeries prior to conversion was 4 (range, 1-9). The median time from the ulnar head implant to the revision surgery was 47 months. Pre- and postoperative pain levels were recorded. Mayo Wrist Scores were calculated. Grip strength, range of motion, and complications and reoperations were recorded. All patients reported moderate or severe pain before surgery, whereas 3 patients reported moderate pain after surgery. The Mayo Wrist Score improved considerably from a median of 50 before surgery to 65 after surgery. The grip strength and forearm pronation-supination showed no change following surgery. The median wrist flexion-extension range improved considerably. Follow-up was a median of 64 (range, 15-132) months after revision surgery. Removal of the ulnar head implant was described as difficult by the surgeons, except in 1 case where the implant was loose. Resection of bone from the distal ulna was often necessary. One patient needed a reoperation requiring prosthesis removal for aseptic loosening of the stem 5 years after revision. There were 2 nondisplaced periprosthetic fractures successfully treated with cast immobilization and 2 additional minor complications, 1 postoperative stitch abscess, and 1 extensor carpi ulnaris tendinitis. Conversion from an ulnar head implant to a semiconstrained prosthesis provided improved pain scores and function with a low reoperation rate in this patient series. Removal of an ulnar head prosthesis can be technically challenging, but it can be performed leaving enough bone stock for immediate implantation of a semiconstrained implant. Therapeutic V.

166. Lumbar total disc replacement as a part of adult scoliosis surgical treatment of 205 patients with minimum of 2 years of follow-up

<h3>BACKGROUND CONTEXT</h3> Surgical scoliosis treatment in adults must face beyond the curve correction, degeneration disc disease, dislocations, spondylolisthesis with sagittal and frontal unbalance and lumbar kyphosis. Two technical components of the surgery have been used to resolve those difficult problems: the fixation through the pelvis, with a complete loss of lumbar mobility and its consequences. The higher rate of pseudarthrosis, despite complex contracts, on one hand, and the necessity of posterior lumbar osteotomies to restore an acceptable lordosis with severe risk of complications on the other hand. <h3>PURPOSE</h3> To explore the capacity to maintain or restore part of mobility and lumbar lordosis, using total disc replacement TDR), by anterior approach (with or without ALIF) in association with the posterior reduction, fixation. <h3>STUDY DESIGN/SETTING</h3> Retrospective clinical study. <h3>PATIENT SAMPLE</h3> A total of 205 patients, 40M, 165F, 18-82 year old (average age 57 yo). Of these, 112 idiopathic scoliosis never operated before, 43 degenerative scoliosis in adults never operated on, and 50 cases already operated on by posterior approach (below prior surgery). A total of 286 TDR Prodisc were implanted (129 - 1 level, 71 - 2 levels, 5 – 3 levels). <h3>OUTCOME MEASURES</h3> The patients' analysis includes the perioperative, preop and postop VAS and ODI (3, 6, 12, 24, late follow-up), mobility of the disc replacement and the evolution of the curve (Cobb, sagittal parameters). <h3>Methods</h3> Between 2000 and 2018, 123 patients with scoliosis and lumbar disc degeneration have received one or more TDR and eventually ALIF, before or after their posterior fixation reduction. The posterior device associated classically hooks, screws, and the rods. The choice of the TDR is one of the key points as with the deformity, there is a need for semi-constrained (fixed center) prosthesis, to neutralize the shear forces and compensate the deficit of anterior and posterior longitudinal ligaments. <h3>Results</h3> ODI preop was 24/50 and declined to 10 in 24 months, VAS lumbar 7.2, radicular 5.7 prep went to 2.6 and 2.1 at 24 months and stabilized at latest follow-up. The mobility measurement at 24 months showed: 151 of 205 patients had a ROM at the TDR level more than 10° in flexion-extension at 24 months. The lordosis capacity of the implants eventually associated to and ALIF with appropriated angulation, allowed the sagittal balance restoration, with T1 axe correction and pelvic tilt reduction. There were no major complications, 4 anterior hematomas (2 drainages, 2 surgical treatments), 2 partial neurological deficits (1 L4, 1 L5). We had no implant TDR complications, no displacements, no explantation required. 2 cases of screw revised, 6 Posterior device removal (2 total, 4 partial), 2 complementary laminectomies, and 2 extension of posterior instrumentation. <h3>Conclusions</h3> The choice of TDR, with a semi – constrained prosthesis and loss restoration of motion and sagittal balance in adult scoliosis. It shows interest in the results, as a clinical and mobility point of view that is maintained in long-term follow up. That allows to avoid the pelvic fixation in majority of cases, escaping for the clinical bad results and complications of the lawn posterior constructions extend it to the pelvis and also illuminates the risks of posterior transpedicular osteotomies. In elderly people, there is a need for osteodensitometry measurement and eventually cementopalsty of the vertebrae that receive the prosthesis. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

A retrospective analysis of trends in primary knee arthroplasty in Germany from 2008 to 2018

Unicompartimental and total knee arthroplasty is one of the most successful and most performed operations worldwide. In the last years the number of primary knee arthroplasty increased constantly. The aim of this study is to analyze the rising numbers of primary knee arthroplasty and to see how it is used in Germany. In this retrospective study data, provided by the Federal Statistical Office of Germany from 2008 to 2018 was analyzed, using operation codes from the German procedure classification system and characteristics like age, sex and type of the prosthesis. We found a slight increase of unicompartimental and total knee arthroplasty over the investigated 10 years from 150.504 in 2008 up to 168.479 procedures in 2018, with a maximum of 169.334 in 2017. Most patients were female and over 65 years old. Interestingly, there was an obvious decrease of regular TKA in the year 2013, with a relevant impact on the total number of procedures. In the following years the number rised again reaching the former level in 2015 and is still increasing. The highest increase was found in partial knee arthroplasty, with a constant rise every year, starting with 7988 in 2008 up to 21.072 in 2018. In contrast, we found a relevant reduction of constrained prosthesis in primary TKA, whereas the number of semi-constrained prosthesis in primary TKA is again rising after a decrease in 2015. We found that the number of bicondylar TKA and especially UKA increased from 2008 to 2018. Regarding an aging population, we can expect a rising number for Primary knee arthroplasty and in consequence a rising number of revision arthroplasty in the future. This will be a challenging cost factor for the healthcare system in Germany.

Revision Total Elbow Arthroplasty with the Semiconstrained Coonrad/Morrey Prosthesis: Follow-up to 21 Years.

Revision total elbow arthroplasty (TEA) has increased, especially in young patients with high functional expectations. The objective of this study was to evaluate the long-term results of revision TEA with a single semiconstrained prosthesis. Thirty-four revision TEAs were performed with a Coonrad/Morrey prosthesis in 32 patients; 2 patients had bilateral procedures. The mean patient age was 61 years (range, 22 to 76 years), and the revision TEA was performed at a mean time of 7.8 years (range, 1.6 to 21 years) after the primary TEA. Etiologies for revisions were humeral and ulnar aseptic loosening (n = 14), ulnar aseptic loosening (n = 8), humeral aseptic loosening (n = 6), septic arthritis (n = 4), and unstable unlinked prostheses (n = 2). Clinical and radiographic evaluations were performed with systematic preoperative infection workup and quantification of bone loss. The mean follow-up was 11.4 years (range, 2 to 21 years). The Mayo Elbow Performance Score (MEPS) at the last follow-up was excellent in 6 cases, good in 18 cases, fair in 8 cases, and poor in 2 cases, with a mean improvement (and standard deviation) between the preoperative values at 42.4 ± 16.1 points and the postoperative values at 81.8 ± 12 points (p < 0.001). The mean pain scores improved significantly from 6.7 ± 1.3 points preoperatively to 1.4 ± 1.4 points postoperatively (p < 0.001). The flexion-extension arc increased significantly (p = 0.02) from 74° ± 27° preoperatively to 100° ± 31° postoperatively. The total number of complications was 29 in 19 revision TEAs (56%). Twenty of the 29 complications simply required monitoring without surgical intervention. Six repeat surgical procedures were required, and 3 implant revisions (9%) were performed. Revision TEA with a semiconstrained prosthesis can provide good clinical results that can be maintained during follow-up. The rate of complications is high. Proper evaluation of the risk-benefit ratio is essential for each revision TEA and should be discussed with the patient. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

P65. Total disc replacement as a part of adult scoliosis surgical treatment of 205 patients with minimum of two years of follow-up

BACKGROUND CONTEXT Surgical scoliosis treatment in adults must face beyond the curve correction, degeneration disc disease, dislocations, spondylolisthesis with sagittal and frontal unbalance and lumbar kyphosis. Two technical components of the surgery have been used to resolve those difficult problems: the fixation through the pelvis, with a complete loss of lumbar mobility and its consequences. The higher rate of pseudarthrosis, despite complex contracts, on one hand, and the necessity of posterior lumbar osteotomies to restore an acceptable lordosis with severe risk of complications on the other hand. PURPOSE To explore the capacity to maintain or restore part of mobility and lumbar lordosis, using total disc replacement TDR), by anterior approach (with or without ALIF) in association with the posterior reduction, fixation. STUDY DESIGN/SETTING Retrospective clinical study. PATIENT SAMPLE A total of 205 patients, 40M, 165F, 18-82 years old (average age 57 yo). Of them, 112 idiopathic scoliosis never operated before, 43 degenerative scoliosis in adults never operated on, and 50 cases already operated on by posterior approach (below prior surgery). Of them, 286 TDR Prodisc implanted (129 - 1 level, 71 - 2 levels, 5 – 3 levels). OUTCOME MEASURES The patients’ analysis includes the perioperative, preop and postop VAS and ODI (3, 6, 12, 24, late follow-up), mobility of the disc replacement and the evolution of the curve (Cobb, sagittal parameters), radiographic analysis. METHODS Between 2000 and 2018, 123 patients with scoliosis and lumbar disc degeneration have received one or more TDR and eventually ALIF, before or after their posterior fixation reduction. The posterior device associated classically hooks, screws and the rods. The choice of the TDR is one of the key points as with the deformity, there is a need for semi-constrained (fixed center) prosthesis, to neutralize the shear forces and compensate the deficit of anterior and posterior longitudinal ligaments. RESULTS ODI preop was 24/50 and declined to 10 in 24 months, VAS lumbar 7.2, radicular 5.7 prep went to 2.6 and 2.1 at 24 months and stabilized at latest follow-up. The mobility measurement at 24 months showed: 151 of 205 patients had a ROM at the TDR level more than 10° in flexion-extension at 24 months. The lordosis capacity of the implants eventually associated to and ALIF with appropriated angulation, allowed the sagittal balance restoration, with T1 axe correction and pelvic tilt reduction. There were no major complications, 4 anterior hematomas (2 drainages, 2 surgical treatments), 2 partial neurological deficits (1 L4, 1 L5). We had no implant TDR complications, no displacements, no explanation required. Two cases of screw revised, 6 posterior device removal (2 total, 4 partial), 2 complementary laminectomies, and 2 extension of posterior instrumentation. CONCLUSIONS The choice of TDR, with a semi–constrained prosthesis and loss restoration of motion and sagittal balance in adult scoliosis. It shows interest in the results, as a clinical and mobility point of view that is maintained in long term follow-up. That allows to avoid the pelvic fixation in majority of cases, escaping for the clinical bad results and complications of the lawn posterior constructions extend it to the pelvis and also illuminates the risks of posterior transpedicular osteotomies. In elderly people, there is a need for osteodensitometry measurement and eventually cementopalsty of the vertebra that receive the prosthesis. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Sagittal alignment of the cemented femoral component in revision total knee arthroplasty influences the anterior and posterior condylar offset: Stem length does not affect these variables

BackgroundThe position of the femoral component can influence knee kinematics by altering the posterior (PCO) and anterior condylar offset (ACO). The primary aim of this study was to assess whether the length of the cemented stem influences the sagittal position of the femoral component after revision total knee arthroplasty (rTKA). The secondary aim was to determine the influence of the sagittal position on PCO and ACO. MethodsThere were 172 consecutive patients over a seven-year period that underwent rTKA with a cemented semi-constrained prosthesis. The 172 patients were separated into two groups: 115 with short stems (50 mm) and 57 with longer stems (100 or 150 mm). Using rotationally acceptable lateral radiographs, the degree of flexion(+)/extension(−) of the femoral components, PCO, and ACO were measured. ResultsThere was no significant difference (p > 0.25) between the two groups for sagittal position, PCO, or ACO. The average flexion of the femoral component with short stems was 2.2 ± 4.1° and 2.2 ± 3.4° for long stems (difference = 0.0, 95% confidence intervals (CI) −1.3 to 1.2). The average PCO ratio was 1.02 ± 0.15 for short stems and 0.99 ± 0.17 for long stems (difference = 0.03, 95% CI −0.02 to 0.08). The average ACO ratio was at 0.07 ± 0.08 for short stems and 0.08 ± 0.08 for long stems (difference = 0.01, 95% CI −0.01 to 0.04). There was a significant correlation between sagittal alignment of the femoral component and PCO (flexion increased PCO, r = 0.39, p < 0.0001) and ACO (flexion decreased ACO, r = −0.34, p < 0.0001). ConclusionsCemented stem length does not influence the position of femoral component in the sagittal axis, PCO, or ACO. Surgical technique and sizing of the femoral component may be more predictive.

Joint replacement surgery in Ghana (West Africa)\u2014an observational study

IntroductionWith the continued and effective transfer of orthopaedic knowledge and skills across continents, the incidence of hip and knee replacement surgery has increased in the developing world. More patients are having these procedures done locally rather than having to travel over to the more developed western countries at great financial costs for those who cannot really afford it. We report the data collected by an orthopaedic charity MOTEC LIFE UK which has been offering hip and knee arthroplasty procedures to patients who require them. The time period of the procedures was February 2013–October 2017.MethodsThe data was collated prospectively and this included age, sex, indication for procedure, and side of procedure (including if bilateral). The information on hip implants used were also collected—implant type (cemented or uncemented), type of bearing surface, size of acetabular cup, liner, femoral head size, and stem size and including if screws were used to augment the fixation of the femoral cup. For the knee implants used, information on the type of implant (semi-constrained, cruciate retaining, or Stanmore hinge knee prosthesis), femoral and tibia stem size, insert type (fixed bearing or mobile bearing), and size; patella button size (whether patella replacement or circumcision) were collected. The surgical approach used in both knee and hip arthroplasty cases was noted.ResultsIt is seen from the data collected that a total of 113 hip arthroplasty procedures from 109 patients were carried out and for total knee replacements, 82 knee arthroplasty procedures from 76 patients were carried out. The above procedures were carried out in two separate hospitals. Degenerative osteoarthritis still remains the main indication for hip and knee arthroplasty surgery in our study and this is similar to other joint registries around the world. It was noted that the incidence of avascular necrosis as an indication hip surgery was higher than that seen in registries for developed countries. The mean age for the hip and knee replacement patient in our data was much lower than that what is obtained in the developed world. Furthermore, it was observed that there was increased use of semi-constrained knee prosthesis due to the severe osteoarthritic deformities noted in the patients seen when compared to rate of use of similar implants in the developed world.ConclusionThis observational study could serve as a springboard for establishment of arthroplasty registries for countries in the sub-region as a whole.

Total elbow arthroplasty in patients with tumor-like lesions of elbow, preliminary results of a single-center experience

Objective The purpose of this study was to investigate the preliminary clinical outcomes of total elbow arthroplasty (TEA) in the treatment of elbow deformity caused by tumor-like lesions. Methods Between September 2009 and June 2017, the technique of triceps facial tongue exposure was adopted for all 11 patients who underwent total elbow arthroplasty. There were 5 females and 6 males with the mean age of 56.7±14.7 years. There were 6patients with synovial chondromatosis and 5 with pathologic hypertrophy of synovium. Seven of 11 patients were performed by posterior approach only, while the other 4by combined posterior-anterior approach. A semi-constrained Coonrad-Morrey prosthesis which provides 7° varus/valgus laxity was used in 7 patients, and custom-made total constrained prosthesis which only allow flexion and extension on a single plane was used in 4 cases. Preoperative average flexion range of elbow was 50.5°±14.0° (range, 20°-70°). The ulnar nerve compression and claw hand deformity was identified in 2patients preoperatively and the nerve was transposed during operation. According to Mayo elbow function score (MEPS score), the average preoperative MEPS score was 42.1±12.7 points (range, 15-60). Results Perioperative complications were not found. None of patients lost in thefollow-up and all the patients were alive. There was no pain in the joints, no triceps fracture or weakening of muscle strength, and no recurrence of the lesions. All 11 patients were followed up for 7 to 63 months with an average of 36.3±19.5 months. The mean MEPS score was improved to 89±7.2 point after surgery (t=-11.993, P= 0.000). The average flextion-extension arc improved from preoperative 50.5° to 105.9° postoperatively (t=-8.697, P=0.000). The average pronation-supination arc improvement from preoperative 105°-123.2° postoperatively (t=-6.901, P=0.000). For the two patients with ulnar nerve deficit before surgery, one patient recovered 6 months after operation, however, the other patient did not 2 years later. One Coonrad-Morrey prosthesis with deep infection was treated by removing the implant. Three of 4 custom-made total constrained prostheses experienced implant failure due to loosening or periprosthetic fracture. The incidence of complications of semi-constrained prosthesis was lower than that of total constrained prosthesis (14% vs. 75%), however, it did not reach a significant difference. Conclusion This study reveals an acceptable outcome with triceps facial tongue exposure for TEA in the treatment of tumor-like lesions of elbow. TEA is a viable good alternative treatment for selected patients with large mass around the elbow or with severe deformation. However, the failure rate of fully constrained prosthesis tends to be higher than semi-constrained one, possible due to its design flaw. Key words: Arthroplasty, replacement, elbow; Paraneoplastic syndromes; Surgical procedures, electiv

Primary Total Knee Arthroplasty (TKA) with revision Total Stabilizer Prosthesis in a 66-year-old patient with secondary knee osteoarthritis and valgus deformity. Case Report

Abstract Knee osteoarthritis (gonarthrosis) is the most prevalent knee pathology encountered nowadays in the third age population, leading to severe disability and reduced life quality. Secondary gonarthrosis may be caused by a traumatic event, which subjects the knee joint to a transitory highly increased mechanical stress, initiating a rapidly progressive degrading process of the articular cartilage and subjacent bone tissue. TKA is intended to replace all the intra-articular components with artificial parts, in order to relieve pain, compensate for ligament instability, correct deformities, and restore proper joint functionality. Semi-constrained, non-hinged implants are usually used for revision TKA, in knees that already had a primary TKA but sustained complications. Nevertheless, here we reported the case of a 66-year-old female patient diagnosed with posttraumatic gonarthrosis who underwent TKA with a revision total stabilizer implant as primary treatment due to severe joint instability and high grade valgus deviation. The outcome of the surgical procedure was positive, with significant pain relief and increased knee stability. The valgus angle was reduced from 37° to 4° and the KSS score increased from 3 to 87 points. Therefore, revision semi-constrained prosthesis may be used as a primary implant with promising result in severe cases.

Distal Radioulnar Joint Replacement in the Scarred Wrist.

Background Radiocarpal or midcarpal arthritis can occur simultaneously with arthritis of the distal radioulnar joint (DRUJ), leading to functional impairment of the wrist. Treatment often involves wrist arthroplasty or arthrodesis, either with simultaneous or secondary procedures, addressing the DRUJ. Successful treatment of solitary DRUJ arthritis with DRUJ replacement has been reported. However, outcomes in patients with multiple prior wrist surgeries are lacking. Surgery in these wrists is challenging because surgical scarring and advanced bone deformities make implant positioning more difficult. Therefore, the aim of this study was to evaluate the outcomes in patients that underwent total wrist arthrodesis and DRUJ replacement after multiple prior wrist surgeries. Methods We prospectively enrolled patients that underwent total wrist arthrodesis and replacement of the DRUJ, either simultaneously or during separate procedures from 1999 to 2012. We included 14 patients with a median age of 43 years (interquartile range [IQR]: 35-47). As objective outcomes range of motion, weight-bearing ability, grip strength, was measured. For the subjective outcomes, we used an analogue pain score and the disabilities of the arm shoulder and hand (DASH) scores. Results At a median follow-up of 5.6 years (IQR: 3.2-7.1). The average DRUJ range of motion and weight lifting ability significantly improved. As for the subjective evaluations, postoperative pain scores improved significantly, as did the DASH scores. Four of the patients had a postoperative complication, including infection and heterotopic ossification, of which two required reoperations. Additionally, 5 patients developed pisotriquetral arthritis requiring, pisiform excision, triquetrum excision, or the combination of both. Conclusion Distal radioulnar joint replacement with a semiconstrained prosthesis was an effective method to restore the function of the wrist and forearm. As the surgical anatomy and soft tissue envelope were compromised in these patients, additional surgical exposure is necessary, adding to the complexity in these patients. No radiographic loosening Level of Evidence This is a therapeutic level IV study.

Discovery Elbow System: clinical and radiological results after 2- to 10-year follow-up.

Discovery Elbow System (DES) is a semi-constrained prosthesis, mainly used for patients with rheumatoid arthritis (RA). Records from 79 patients with RA (90 DES arthroplasties) were reviewed; 47 patients with 55 DES elbows were re-examined. Range of motion (ROM) of both elbows, upper limb function, and quality of life (Disabilities of the Arm, Shoulder, and Hand [DASH] score, Mayo Elbow Performance Score [MEPS], and the RAND 36-Item Health Survey [RAND-36]) were assessed. Cementing quality was assessed, and radiolucent lines measured from plain radiographs. Mean follow-up was 64 (range 24-123) months. Pre-operatively to post-operatively, mean elbow flexion improved from 120° to 146° (p<0.001) and mean extension lag improved from 29° to 24° (p=0.02), respectively. At follow-up, mean supination was 66°, mean pronation was 69°, and mean grip strength was 14kg. Grip strength and ROM (except supination) were similar between the DES elbow and contralateral un-operated elbow. Mean post-operative MEPS was 93 points (excellent, n=38; good, n=14; fair, n=2; and poor, n=1). Mean DASH score was 43 points. The RAND-36 showed that physical functioning, physical role functioning, bodily pain, and general health were lower than the Finnish reference values. Primary cementing was challenging, and radiolucent lines appeared during follow-up. Four prostheses were revised because of aseptic loosening (n=3) and periprosthetic fracture (n=1). DES provides significant improvement in patient's flexion-extension arc. Cementing of the elbow prosthesis was challenging; radiolucent lines appeared during the 5-year follow-up, but their clinical relevance remains unclear. First-generation locking screws may loosen over time. Level IV.

One-stage computer-assisted total knee arthroplasty and tibial osteotomy

Same-stage tibial osteotomy may deserve consideration in candidates to total knee arthroplasty (TKA) who have severe bone deformities, particularly at extra-articular sites. This strategy obviates the need for either a major and technically difficult ligament release procedure, which may compromise ligament balancing, or the use of a semi-constrained prosthesis. This technical note describes a one-stage, computer-assisted technique consisting in TKA, followed by corrective tibial osteotomy to obtain an overall mechanical axis close to 180° without extensive ligament balancing. This technique provided satisfactory outcomes in 8 patients followed-up for at least 3years, with no specific complications or ligament instability and with a hip-knee-ankle angle close to 180°. After planning, intra-operative computer assistance ensures accurate determination of both implant position and the degree of correction achieved by the osteotomy.

Condylar constrained system in primary total knee replacement: our experience and literature review.

Constrained condylar knee (CCK) prosthesis are common used for revision surgery but can also help surgeons to improve implant stability in primary knee arthroplasty, in fact in severe knee arthrosis with serious deformity associated with a significant instability a more constrained articulation is required. With introduction of second generation of semi-constrained prosthesis, rate of complication is real decreased and a good survival rate and functional score results is showed. In this paper we write about our experience using CCK in primary knee arthroplasty. Between January 2012 and December 2015, 28 second-generation semi-constrained knee arthroplasties were performed as a first implant. Two different types of implants were used: 10 constrained condylar knee (CCK Zimmer) and 18 TC3 (DePuy Johnson & Johnson). All patients were over 75 years old (mean 81.75) with a severe deformity and clinical evaluations at 2-, 6-, 12-month after surgery and every year performed. X-rays at 6, 12 months and then annually was planned with an average follow-up of 31.28 (range 6-48) months. No patients were lost during the follow-up. The mean functional knee society score (KSS) improved from 30 points preoperatively to 92.1 points at the last follow-up. All patients recovered full extension during follow-up and no radiolucent lines were showed at X-ray control. There were no deep infections or peri-prosthetic fractures. Second generation semi-constrained knee prosthesis represent safe and practical treatment in primary total knee arthroplasty (TKA) in case of severe deformity that can't be managed with accurate soft tissue release, especially in elderly patients.