Platelet concentrate injection improves Achilles tendon repair in rats

BACKGROUND: Blood platelets release a cocktail of growth factors when activated, some of which are thought to initiate and stimulate repair. EXPERIMENT AND FINDINGS: We studied whether a platelet concentrate injection would improve Achilles tendon repair in an established rat model. The Achilles tendon was transected and a 3 mm segment removed. After 6 h, a platelet concentrate was injected percutaneously into the hematoma. This increased tendon callus strength and stiffness by about 30% after 1 week, which persisted for as long as 3 weeks after the injection. At this time, the mechanical testing indicated an improvement in material characteristics--i.e., greater maturation of the tendon callus. This was confirmed by blinded histological scoring. INTERPRETATION: Platelet concentrate may prove useful for the treatment of Achilles tendon ruptures.     

An Alternative Method for Exchange Operation of Infected Arthroplasty

The use of bone cement balls in chains loaded with gentamycin (gentamycin-PMMA-ketten) as part of a two-stage exchange operation has proven to be a good method of treatment for infected arthroplasty. The procedure is illustrated by three case reports.     

Revision Hip Arthroplasty: A Retrospective Survey

A survey of revision hip arthroplasties was performed, using a retrospective review of the patients' case notes and radiographs, and an assessment of the patients, at least 1 year after the revision. The patients were divided into three categories: a) First revision hip arthroplasty (41 patients); b) Second revision hip arthroplasty (8 patients); c) Revision of femoral hemi-arthroplasty (14 patients). The reasons for revision, the type of revision and the final outcome have been identified in each group. This is the first study which allows direct comparison of the final outcome, as assessed by accurate objective criteria, between patients having revision hip arthroplasty for different reasons. Radiographs of the hip arthroplasty after the original operation and after revision have been analysed.

The final outcome of first revision hip arthroplasty and revision of hemi-arthroplasty to total hip replacement was generally good. The outcome of second revision hip arthroplasty was generally poor.     

Revision Hip Arthroplasty: A Retrospective Survey

A survey of revision hip arthroplasties was performed, using a retrospective review of the patients' case notes and radiographs, and an assessment of the patients, at least 1 year after the revision. The patients were divided into three categories: a) First revision hip arthroplasty (41 patients); b) Second revision hip arthroplasty (8 patients); c) Revision of femoral hemi-arthroplasty (14 patients). The reasons for revision, the type of revision and the final outcome have been identified in each group. This is the first study which allows direct comparison of the final outcome, as assessed by accurate objective criteria, between patients having revision hip arthroplasty for different reasons. Radiographs of the hip arthroplasty after the original operation and after revision have been analysed.

The final outcome of first revision hip arthroplasty and revision of hemi-arthroplasty to total hip replacement was generally good. The outcome of second revision hip arthroplasty was generally poor.     

Nonoperative treatment of Achilles tendon rupture

Background The best treatment for acute Achilles tendon rupture is unknown.

Patients and methods We assessed the outcome of nonoperative treatment in 196 consecutive individuals with an acute total Achilles tendon rupture who were followed until healing. The mean duration of treatment in cast or orthosis was 8 weeks. After 4 years, a questionnaire was sent to all patients who were still alive (182) to supplement and confirm the retrospective data. The questionnaire was completed by 176/182 patients (97%).

Results The re-rupture frequency was 7% (n?=?14). 7 patients suffered other complications (7 deep venous thrombosis and 1 pulmonary embolism). At follow-up, 62% of the patients reported full recovery.

Interpretation The low re-rupture rate after nonoperative treatment challenges the claim in recent studies that acute rupture of the Achilles tendon should be operated.     

A modified cement spacer technique for infected total hip arthroplasties with significant bone loss

Complications related to femoral spacers are common during addressing infected total hip arthroplasties by 2-stage revision. We evaluated 11 patients who had 2-stage revisions with massive bone loss after removal of the infected components by a trochanteric osteotomy. All femoral cement spacers were assembled on intramedullary nails. Femurs were protected by a plate, whereas acetabuli were augmented by a cage or roof ring depending on the remaining bone stock. This additional hardware was covered with antibiotic-impregnated cement. Infection was eradicated in 10 (90.9%) of 11 patients within 3.5 months in average. None of the patients had spacer fracture, periprosthetic fracture, or dislocation. Augmentation by hardware covered with antibiotic-impregnated cement is effective and may reduce complications until definitive treatment is performed.     

Surgical treatment of Achilles tendon rupture

Background The mechanical properties of present-day percutaneous repairs of Achilles tendon ruptures are not known.

Material and methods Artificially-created ruptures in 24 human cadaveric Achilles tendons were repaired with an open Bunnell repair, a percutaneous calcaneal tunnel or a percutaneous bone-anchor repair. In the open technique no.1 PDS-II absorbable suture material was used, and in the percutaneous techniques either no.1 PDS-II or no.1 Panacryl absorbable suture material was used. The specimens were tested in a materials testing machine until failure occurred.

Results The common mode of failure was suture breakage in non-anchor repairs, and anchor pullout in anchor repairs. The average strength of the repairs varied from 166 N (SD 60) to 211 N (SD 30), with no differences between the techniques (p = 0.5).

Interpretation Taking costs into account, the percutaneous calcaneal tunnel technique and the open technique are the methods of choice.     

Periprosthetic Joint Infections Treated with Two-Stage Revision over 14 Years: An Evolving Microbiology Profile

Late periprosthetic joint infection (PJI) occurs in 0.3%–1.7% of total hip arthroplasties (THAs) and 0.8%–1.9% of total knee arthroplasties (TKAs). Surgical debridement, explant, and appropriate antibiotics are imperative for successful treatment. We analyzed organisms from PJIs at one institution for temporal trends over 14 years. Poisson regression model demonstrated a linear increase in infection rate for the following bacteria as the primary organism: MRSA (incidence rate ratio [IRR] = 1.11, P = 0.019), Streptococcus viridans (IRR = 1.18, P = 0.002), and Propionibacterium acnes (IRR = 1.21, P = 0.024). The increase in proportion of these organisms may warrant further discussion on pre-surgical MRSA screening and empiric therapy to include MRSA coverage, increased incubation time to detect P. acnes, and dental prophylaxis against S. viridans.     

2021年度关节外科手术机器人临床应用年度盘点

全关节置换术是治疗各种终末期关节疾病的有效治疗手段，随着我们努力完善技术并改善患者预后，该手术仍在不断发展。机器人辅助关节置换手术始于20世纪80年代的“主动型” ROBODOC系统，随着精准化、微创化及快速康复等理念的推广，国内外机器人不断涌现，进一步推动国内外机器人的发展。本文回顾了2021年有关关节外科手术机器人临床应用研究的文献，客观、全面地评价其在关节置换中的临床价值及应用前景。     

Unfavorable effect of knee immobilization on Achilles tendon healing in rabbits

This study was undertaken to assess the effect of knee immobilization on the treatment of Achilles tendon rupture. After their Achilles tendons were severed, rabbits were divided into 2 groups. In Group A, only the ankle joint was immobilized. In Group B, both the knee and ankle joints were immobilized. At 4 weeks after surgery, both the ultimate tensile force and stiffness of the severed tendons were significantly greater in Group A than in Group B. In Group A, dense collagen fibers were seen in the repaired tendons, and the bundles of collagen fibers were parallel to one another along the axis of the tendons. In contrast, in Group B, dilated veins and capillaries were seen in the repaired tendons, and the proliferation of connective tissue containing collagen fibers was severely reduced around these veins and capillaries and was in general irregular and uneven. These results suggest that knee immobilization retards the healing of a ruptured Achilles tendon without suture, due to congestion and tension deprivation produced by keeping the tendon static.     

In-Hospital Surgical Site Infections after Primary Hip and Knee Arthroplasty — Incidence and Risk Factors

Data of hospitalizations for THA or TKA were analyzed for each year between 1998 and 2007 from the National Inpatient Sample. Demographics, comorbidities, incidence of morbidity and mortality, length of hospital stay (LOS), and overall cost were compared for infected and non-infected patients. Perioperative SSI rates were 0.36% for THA and 0.31% for TKA (412,356 and 784,335 patient entries, respectively). Patients with SSI had a significantly higher overall comorbidity burden, higher perioperative mortality rates, longer length of stay, and higher complication rates. Average cost of in-hospital care was double for SSI versus non-SSI patients. Independent risk factors for perioperative SSI included male gender, minority race, a diagnosis for cancer, liver disease, coagulopathies, fluid and electrolyte disorders, congestive heart failure, and pulmonary circulatory disease. Data relied on coded information and could not differentiate between superficial or deep infection, or capture patients readmitted for SSI, and therefore may have underestimated the true incidence of SSI.     

Joint Replacement Access in 2016 : A Supply Side Crisis

Demand for primary and revision arthroplasty is expected to double in 10 years. Coincident with this is a decreased interest in arthroplasty by residents. Retirement of arthroplasty surgeons further threatens access. This study determines if supply will meet demand. Survey data were used to calculate the 2016 workforce. Demand in 2016 was estimated using the Nationwide Inpatients Sample. Between 2008 and 2016, 400 arthroplasty specialists and 1584 generalists will enter the workforce. By 2016, 1896 arthroplasty surgeons will retire using 65 years as a conservative retirement age, whereas 4239 will retire using 59 years as a baseline retirement age. In 2016, the model estimated a procedural shortfall ranging from 174?409 (↓18.6%) using conservative retirement assumptions (age, 65 years) to 1?177?761 (↓69.4%) using baseline retirement assumptions (age, 59 years). This economic model predicts a supply side crisis that threatens patient access to specialty care. Immediate steps to stimulate supply must be taken.     

Open repair of the acutely torn Achilles tendon under local anaesthetic

Background: Where surgery has been preferred, the torn Achilles tendon (AT) has most commonly been repaired under general or spinal anaesthetic (GA). Repair using local anaesthetic (LA) has been reported, but does not appear to be widely used. Methods: We retrospectively reviewed 87 patients, following open repair using either GA or LA at Nelson Hospital, 2001–2005. Calf strength and ankle range of motion (ROM) were assessed. Subjective pain and function were assessed using the American Academy of Orthopaedic Surgeons Foot and Ankle Questionnaire. Complications, time off work and sport, time in theatre, and hospital were recorded. Results: Fifty‐nine tendons were repaired under GA (68%) and 28 under LA (32%). Outcomes were similar for each group. There was no significant difference in strength and ROM. Foot and Ankle Questionnaire scores were similar. Total theatre time averaged 57 min for GA and 37 min for LA (P = 0.01). LA repairs (82%) were performed as a day case compared with 10% of the GA repairs (P = 0.01). LA patients had a quicker return to work. GA complications included two deep vein thromboses and two pulmonary emboli. One patient from each group had a re‐rupture. Conclusion: A repair of the acutely ruptured AT under LA is at least as effective as repair under GA with regard to function, long‐term pain and patient satisfaction. LA repair results in significant cost savings due to less theatre time, fewer anaesthetic costs, and a shorter hospital stay.     

Suture anchor repair of quadriceps tendon rupture after total knee arthroplasty

Disruption of the extensor mechanism after total knee arthroplasty (TKA) is a devastating complication, usually requiring surgical repair. Although suture anchor fixation is well described for repair of the ruptured native knee quadriceps tendon, no study has discussed the use of suture anchors in quadriceps repair after TKA. We present an illustrative case of successful suture anchor fixation of the quadriceps mechanism after TKA. The procedure has been performed in a total of 3 patients. A surgical technique and brief review of the literature follows. Suture anchor fixation of the quadriceps tendon is a viable option in the setting of rupture after TKA.     

High Rate of Reinfection With New Bacteria Following One-Stage Exchange for Enterococcal Periprosthetic Infection of the Knee: A Single-Center Study

BackgroundA wide range of success rates following the surgical management of enterococcal periprosthetic joint infection (PJI) with a tendency toward worse outcomes have been reported. However, the role of 1-stage exchange remains under-investigated. Therefore, we aimed to evaluate our results after the 1-stage knee exchange for enterococcal PJI.MethodsForty patients were retrospectively included between 2002 and 2017 with a mean follow-up of survivors of 80 months (range 22-172; standard deviation [SD] = 5). Polymicrobial infections occurred in 45% (18/40) of patients. Patients’ characteristics, joint-related data, and antibiotic therapy were recorded. Rates of enterococcal infection relapse, reinfection with new microorganisms, and re-revision for any reason were determined. Bivariate analysis was conducted to identify risk factors of infection recurrence.ResultsRevision surgery was required in 22 cases (55%) with a mean time to revision surgery of 27 months (range 1-78; SD = 25). Indications for aseptic revisions (18%) included aseptic loosening (10%), periprosthetic fracture (5%), and patellar instability (3%). The most common cause of re-revision was a subsequent PJI (15/22; 68%) after a mean time of 22 months (range 1-77; SD = 24). Overall infection recurrence rate was 37.5% (15/40), substantially due to entirely non-enterococcal infections (9/15; 60%). Infection relapse with Enterococci occurred in 4 cases (10%) within 16 months postoperatively. Older patients (P = .05) and male gender (P = .05) were associated with a higher risk of infection recurrence.ConclusionOvercoming the Enterococci using the 1-stage exchange for knee PJI is achievable but the rate of reinfection due to new microorganisms is high . However, the overall infection recurrence rate is comparable to other treatment approaches.     

Alignment of computer-assisted total knee arthroplasty in patients with altered hip center

This study aimed to determine limb and component alignment after computer-assisted total knee arthroplasty in 30 patients (32 limbs) with an altered hip center due to a prior hip implant or deformed femoral head. There were no outliers greater than ±3° in the postoperative coronal alignment of the limb and the femoral component in relation to the altered hip center. Two limbs (8%) were more than ±3° for coronal alignment of the femoral component in relation to the anatomical hip center and 96% of limbs had less than 2° deviation in relation to the altered hip center. Computer-navigated total knee arthroplasty results in accurate restoration of lower limb and component alignment in patients with prior hip implants or deformed femoral heads where accurate restoration of alignment may be challenging due to altered hip center.     

Identifying and Creating Value for Employed Arthroplasty Surgeons in an Era of Decreasing Reimbursement

Recent regulatory changes made by the Center for Medicare and Medicaid Services (CMS) will result in a 9% decrease in reimbursement for hip and knee replacements by the end of 2022. Combining this with CMS’s recent removal of total knee and total hip arthroplasty from the inpatient-only list has begun to take effect on the bottom line for hospital systems, which now employ around 50% of the arthroplasty community. Employed joint replacement surgeons should continue to innovate and be leaders within their hospital systems in the outpatient and ambulatory surgery space to recoup lost value, increase autonomy, and should be compensated for this work. Employed arthroplasty surgeon leaders can better align goals with and control the narrative in the C-suite to redefine their value as the most consistent, dependable, and transparent department within a larger health system or corporate medical group.     

Thromboembolic disease in patients with rheumatoid arthritis undergoing joint arthroplasty: Update on prophylaxes

The risk of venous thromboembolism (VTE) in rheumatoid arthritis (RA) and the higher incidence of RA patients undergoing major orthopedic surgery is well recognized. The objective of the present study is to describe the incidence of VTE and discuss the correct prophylaxis in RA patients undergoing knee or hip replacement. A systematic review of studies on thromboprophylaxis in RA patients undergoing major orthopedic surgery was performed. Detailed information was extracted to calculate the rate of VTE in RA orthopedic patients and analyze the thromboprophylaxis performed and bleeding complications. Eight articles were eligible for full review. No difference in the overall rate of VTE was observed between RA patients and controls. No significant differences were found in RA patients in terms of bleeding complications. The data on the optimal prophylaxis to be used in RA patients were insufficient to recommend any of the several options available. In the absence of dedicated guidelines for the care of RA patients undergoing orthopedic surgery, management must be individualized to obtain favorable patient outcome, weighing up all the factors that might put the patient at risk for higher bleeding and thrombotic events.     

Pulsed ultrasound treatment accelerates the repair of Achilles tendon rupture in rats.

A rat tenotomy model was used to investigate the effect of combined conservative management and pulsed ultrasound (PUS) on the repair of tenotomized Achilles tendon. Hemitenotomy of right medial Achilles tendon was performed in 48 rats without suture, and patella tenotomy was performed to mimic immobilization and limb disuse of an injured limb. PUS and sham PUS were applied to the healing wound for the treatment group and control group for 5 min, 3 times per week for 2 or 4 weeks, respectively. Tensile tests showed that the ultimate tensile strength (UTS) and stiffness of the repaired tendon in the treatment group at 2 weeks reached 48.92+/-8.39% and 62.48+/-32.46% of the contralateral normal tendon strength, which were significantly higher than those of the control group (UTS, 30.36+/-15.46%; stiffness, 33.90+/-17.59; p<0.05). At 4 weeks, UTS increased to 77.09+/-15.31% and stiffness to 92.48+/-31.12% in the treatment group, significantly higher than those in the control group (UTS, 54.33+/-18.40%, p<0.01; stiffness, 65.02+/-25.48%, p<0.05). Light microscopy revealed more regular, denser, and better aligned collagen fibers in the healing scar of the PUS-treated healing tendons. The findings suggested that PUS were able to accelerate the healing of the ruptured tendons.